ID: 24488099
Title: High sphingomyelin levels induce lysosomal damage and autophagy dysfunction in Niemann Pick disease type A.
Abstract: Niemann Pick disease type A (NPA), which is caused by loss of function mutations in the acid sphingomyelinase (ASM) gene, is a lysosomal storage disorder leading to neurodegeneration. Yet, lysosomal dysfunction and its consequences in the disease are poorly characterized. Here we show that undegraded molecules build up in neurons of acid sphingomyelinase knockout mice and in fibroblasts from NPA patients in which autophagolysosomes accumulate. The latter is not due to alterations in autophagy initiation or autophagosome-lysosome fusion but because of inefficient autophago-lysosomal clearance. This, in turn, can be explained by lysosomal membrane permeabilization leading to cytosolic release of Cathepsin B. High sphingomyelin (SM) levels account for these effects as they can be induced in control cells on addition of the lipid and reverted on SM-lowering strategies in ASM-deficient cells. These results unveil a relevant role for SM in autophagy modulation and characterize autophagy anomalies in NPA, opening new perspectives for therapeutic interventions.

ID: 26521126
Title: Ubiquilin-2 drives NF-κB activity and cytosolic TDP-43 aggregation in neuronal cells.
Abstract: Mutations in the gene encoding Ubiquilin-2 (UBQLN2) are linked to amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). UBQLN2 plays a central role in ubiquitin proteasome system (UPS) and UBQLN2 mutants can form cytoplasmic aggregates in vitro and in vivo. Here, we report that overexpression of WT or mutant UBQLN2 species enhanced nuclear factor κB (NF-κB) activation in Neuro2A cells. The inhibition of NF-κB stress-mediated activation with SB203580, a p38 MAPK inhibitor, demonstrated a role for MAPK in NF-κB activation by UBQLN2 species. Live cell imaging and microscopy showed that UBQLN2 aggregates are dynamic structures that promote cytoplasmic accumulation of TAR DNA-binding protein (TDP-43), a major component of ALS inclusion bodies. Furthermore, up-regulation of UBQLN2 species in neurons caused an ER-stress response and increased their vulnerability to death by toxic mediator TNF-α. Withaferin A, a known NF-κB inhibitor, reduced mortality of Neuro2A cells overexpressing UBQLN2 species. These results suggest that UBQLN2 dysregulation in neurons can drive NF-κB activation and cytosolic TDP-43 aggregation, supporting the concept of pathway convergence in ALS pathogenesis. These Ubiquilin-2 pathogenic pathways might represent suitable therapeutic targets for future ALS treatment.

ID: 26663083
Title: Deficiency of Neuronal p38α MAPK Attenuates Amyloid Pathology in Alzheimer Disease Mouse and Cell Models through Facilitating Lysosomal Degradation of BACE1.
Abstract: Amyloid β (Aβ) damages neurons and triggers microglial inflammatory activation in the Alzheimer disease (AD) brain. BACE1 is the primary enzyme in Aβ generation. Neuroinflammation potentially up-regulates BACE1 expression and increases Aβ production. In Alzheimer amyloid precursor protein-transgenic mice and SH-SY5Y cell models, we specifically knocked out or knocked down gene expression of mapk14, which encodes p38α MAPK, a kinase sensitive to inflammatory and oxidative stimuli. Using immunological and biochemical methods, we observed that reduction of p38α MAPK expression facilitated the lysosomal degradation of BACE1, decreased BACE1 protein and activity, and subsequently attenuated Aβ generation in the AD mouse brain. Inhibition of p38α MAPK also enhanced autophagy. Blocking autophagy by treating cells with 3-methyladenine or overexpressing dominant-negative ATG5 abolished the deficiency of the p38α MAPK-induced BACE1 protein reduction in cultured cells. Thus, our study demonstrates that p38α MAPK plays a critical role in the regulation of BACE1 degradation and Aβ generation in AD pathogenesis.

ID: 27753622
Title: VCP/p97 cooperates with YOD1, UBXD1 and PLAA to drive clearance of ruptured lysosomes by autophagy.
Abstract: Rupture of endosomes and lysosomes is a major cellular stress condition leading to cell death and degeneration. Here, we identified an essential role for the ubiquitin-directed AAA-ATPase, p97, in the clearance of damaged lysosomes by autophagy. Upon damage, p97 translocates to lysosomes and there cooperates with a distinct set of cofactors including UBXD1, PLAA, and the deubiquitinating enzyme YOD1, which we term ELDR components for Endo-Lysosomal Damage Response. Together, they act downstream of K63-linked ubiquitination and p62 recruitment, and selectively remove K48-linked ubiquitin conjugates from a subpopulation of damaged lysosomes to promote autophagosome formation. Lysosomal clearance is also compromised in MEFs harboring a p97 mutation that causes inclusion body myopathy and neurodegeneration, and damaged lysosomes accumulate in affected patient tissue carrying the mutation. Moreover, we show that p97 helps clear late endosomes/lysosomes ruptured by endocytosed tau fibrils. Thus, our data reveal an important mechanism of how p97 maintains lysosomal homeostasis, and implicate the pathway as a modulator of degenerative diseases.

ID: 28542436
Title: Stress-induced release of Oct-1 from the nuclear envelope is mediated by JNK phosphorylation of lamin B1.
Abstract: The nuclear lamina can bind and sequester transcription factors (TFs), a function lost if the lamina is abnormal, with missing or mutant lamin proteins. We now show that TF sequestration is not all-or-nothing, but a dynamic physiological response to external signals. We show that the binding of the ubiquitous TF, Oct-1, to lamin B1 was reversed under conditions of cellular stress caused, inter alia, by the chemical methylating agent methylmethanesulfonate (MMS). A search for lamin B1 post-translational modifications that might mediate changes in Oct-1 binding using kinase inhibitors uncovered a role for c-Jun N-terminal kinase (JNK). Phosphoproteomic and site-directed mutagenesis analyses of lamin B1 isolated from control and MMS-treated nuclei identified T575 as a JNK site phosphorylated after stress. A new phospho-T575 specific anti-peptide antibody confirmed increased interphase cellular T575 phosphorylation after cell exposure to certain stress conditions, enabling us to conclude that lamin B1 acts as an interphase kinase target, releasing Oct-1 to execute a protective response to stress.

ID: 29176575
Title: Phosphorylation of LAMP2A by p38 MAPK couples ER stress to chaperone-mediated autophagy.
Abstract: Endoplasmic reticulum (ER) and lysosomes coordinate a network of key cellular processes including unfolded protein response (UPR) and autophagy in response to stress. How ER stress is signaled to lysosomes remains elusive. Here we find that ER disturbance activates chaperone-mediated autophagy (CMA). ER stressors lead to a PERK-dependent activation and recruitment of MKK4 to lysosomes, activating p38 MAPK at lysosomes. Lysosomal p38 MAPK directly phosphorylates the CMA receptor LAMP2A at T211 and T213, which causes its membrane accumulation and active conformational change, activating CMA. Loss of ER stress-induced CMA activation sensitizes cells to ER stress-induced death. Neurotoxins associated with Parkinson's disease fully engages ER-p38 MAPK-CMA pathway in the mouse brain and uncoupling it results in a greater loss of SNc dopaminergic neurons. This work identifies the coupling of ER and CMA as a critical regulatory axis fundamental for physiological and pathological stress response.

ID: 29196611
Title: Cell signaling abnormalities in cardiomyopathy caused by lamin A/C gene mutations.
Abstract: Mutations in the lamin A/C gene (LMNA) encoding intermediate filament proteins associated with the inner nuclear membrane cause diseases known as laminopathies. Most LMNA mutations cause dilated cardiomyopathy with variable skeletal muscular dystrophy. Cell signaling abnormalities have been discovered in hearts of mouse models of cardiomyopathy caused by LMNA mutations that contribute to pathogenesis. These include abnormally increased signaling by extracellular signal-regulated kinase 1 and kinase 2 and other mitogen-activated protein kinases, protein kinase B/mammalian target of rapamycin complex 1 and transforming growth factor-β. Preclinical research suggests that specific inhibitors of these abnormally activated cell signaling pathways may be useful in treating human patients with this disease.

ID: 29789529
Title: Inhibiting p38 MAPK alpha rescues axonal retrograde transport defects in a mouse model of ALS.
Abstract: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease caused by the degeneration of upper and lower motor neurons. Defects in axonal transport have been observed pre-symptomatically in the SOD1G93A mouse model of ALS, and have been proposed to play a role in motor neuron degeneration as well as in other pathologies of the nervous system, such as Alzheimer's disease and hereditary neuropathies. In this study, we screen a library of small-molecule kinase inhibitors towards the identification of pharmacological enhancers of the axonal retrograde transport of signalling endosomes, which might be used to normalise the rate of this process in diseased neurons. Inhibitors of p38 mitogen-activated protein kinases (p38 MAPK) were identified in this screen and were found to correct deficits in axonal retrograde transport of signalling endosomes in cultured primary SOD1G93A motor neurons. In vitro knockdown experiments revealed that the alpha isoform of p38 MAPK (p38 MAPKα) was the sole isoform responsible for SOD1G93A-induced transport deficits. Furthermore, we found that acute treatment with p38 MAPKα inhibitors restored the physiological rate of axonal retrograde transport in vivo in early symptomatic SOD1G93A mice. Our findings demonstrate the pathogenic effect of p38 MAPKα on axonal retrograde transport and identify a potential therapeutic strategy for ALS.

ID: 34394034
Title: Staphylococcus aureus α-Toxin Induces Acid Sphingomyelinase Release From a Human Endothelial Cell Line.
Abstract: Staphylococcus aureus (S. aureus) is well known to express a plethora of toxins of which the pore-forming hemolysin A (α-toxin) is the best-studied cytolysin. Pore-forming toxins (PFT) permeabilize host membranes during infection thereby causing concentration-dependent effects in host cell membranes ranging from disordered ion fluxes to cytolysis. Host cells possess defense mechanisms against PFT attack, resulting in endocytosis of the breached membrane area and delivery of repair vesicles to the insulted plasma membrane as well as a concurrent release of membrane repair enzymes. Since PFTs from several pathogens have been shown to recruit membrane repair components, we here investigated whether staphylococcal α-toxin is able to induce these mechanisms in endothelial cells. We show that S. aureus α-toxin induced increase in cytosolic Ca2+ in endothelial cells, which was accompanied by p38 MAPK phosphorylation. Toxin challenge led to increased endocytosis of an extracellular fluid phase marker as well as increased externalization of LAMP1-positive membranes suggesting that peripheral lysosomes are recruited to the insulted plasma membrane. We further observed that thereby the lysosomal protein acid sphingomyelinase (ASM) was released into the cell culture medium. Thus, our results show that staphylococcal α-toxin triggers mechanisms in endothelial cells, which have been implicated in membrane repair after damage of other cell types by different toxins.

ID: 36283391
Title: Changes in nuclear pore numbers control nuclear import and stress response of mouse hearts.
Abstract: Nuclear pores are essential for nuclear-cytoplasmic transport. Whether and how cells change nuclear pores to alter nuclear transport and cellular function is unknown. Here, we show that rat heart muscle cells (cardiomyocytes) undergo a 63% decrease in nuclear pore numbers during maturation, and this changes their responses to extracellular signals. The maturation-associated decline in nuclear pore numbers is associated with lower nuclear import of signaling proteins such as mitogen-activated protein kinase (MAPK). Experimental reduction of nuclear pore numbers decreased nuclear import of signaling proteins, resulting in decreased expression of immediate-early genes. In a mouse model of high blood pressure, reduction of nuclear pore numbers improved adverse heart remodeling and reduced progression to lethal heart failure. The decrease in nuclear pore numbers in cardiomyocyte maturation and resulting functional changes demonstrate how terminally differentiated cells permanently alter their handling of information flux across the nuclear envelope and, with that, their behavior.

ID: 39541976
Title: Lysosomal damage triggers a p38 MAPK-dependent phosphorylation cascade to promote lysophagy via the small heat shock protein HSP27.
Abstract: Maintenance of lysosomal integrity is essential for cell viability. Upon injury, lysosomes may be targeted for degradation via a selective form of autophagy known as lysophagy. The engulfment of a damaged lysosome by an autophagosome is mediated by the recruitment of adaptor proteins, including SQSTM1/p62. p62 promotes lysophagy via the formation of phase-separated condensates in a mechanism that is regulated by the heat shock protein HSP27. Here, we demonstrate a direct interaction between HSP27 and p62. We used structural modeling to predict the binding interface between HSP27 and p62 and identify several disease-associated mutations that map to this interface. We used proteomics to identify post-translational modifications of HSP27 that regulate HSP27 recruitment to stressed lysosomes, finding robust phosphorylation at several serine residues. Next, we characterized the upstream signaling mechanism leading to HSP27 phosphorylation and found that p38 mitogen-activated protein kinase (MAPK) and its effector kinase MAP kinase-activated protein kinase 2 (MK2) are activated upon lysosomal damage by the kinase mTOR and the production of intracellular reactive oxygen species (ROS). Increased ROS activates p38 MAPK, which in turn allows MK2-dependent phosphorylation of HSP27. Depletion of HSP27 or the inhibition of HSP27 phosphorylation alters the dynamics of p62 condensates on stressed lysosomes, significantly inhibiting p62-dependent lysophagy. Thus, we define a novel lysosomal quality control mechanism in which lysosomal injury triggers a p38 MAPK/MK2 signaling cascade promoting p62-dependent lysophagy. Further, this signaling cascade is activated by many cellular stressors, including oxidative and heat stress, suggesting that other forms of selective autophagy may be regulated by p38 MAPK/MK2/HSP27.

ID: 39602452
Title: Coronavirus nucleocapsid protein enhances the binding of p-PKCα to RACK1: Implications for inhibition of nucleocytoplasmic trafficking and suppression of the innate immune response.
Abstract: The hallmark of coronavirus infection lies in its ability to evade host immune defenses, a process intricately linked to the nuclear entry of transcription factors crucial for initiating the expression of antiviral genes. Central to this evasion strategy is the manipulation of the nucleocytoplasmic trafficking system, which serves as an effective target for the virus to modulate the expression of immune response-related genes. In this investigation, we discovered that infection with the infectious bronchitis virus (IBV) dynamically impedes the nuclear translocation of several transcription factors such as IRF3, STAT1, STAT2, NF-κB p65, and the p38 MAPK, leading to compromised transcriptional induction of key antiviral genes such as IFNβ, IFITM3, and IL-8. Further examination revealed that during the infection process, components of the nuclear pore complex (NPC), particularly FG-Nups (such as NUP62, NUP153, NUP42, and TPR), undergo cytosolic dispersion from the nuclear envelope; NUP62 undergoes phosphorylation, and NUP42 exhibits a mobility shift in size. These observations suggest a disruption in nucleocytoplasmic trafficking. Screening efforts identified the IBV nucleocapsid (N) protein as the agent responsible for the cytoplasmic distribution of FG-Nups, subsequently hindering the nuclear entry of transcription factors and suppressing the expression of antiviral genes. Interactome analysis further revealed that the IBV N protein interacts with the scaffold protein RACK1, facilitating the recruitment of activated protein kinase C alpha (p-PKCα) to RACK1 and relocating the p-PKCα-RACK1 complex to the cytoplasm. These observations are conserved across diverse coronaviruses N proteins. Concurrently, the presence of both RACK1 and PKCα/β proved essential for the phosphorylation and cytoplasmic dispersion of NUP62, the suppression of antiviral cytokine expression, and efficient virus replication. These findings unveil a novel, highly effective, and evolutionarily conserved mechanism.

ID: 41887951
Title: Repair condensates and lipid domains in lysosome integrity.
Abstract: Lysosomes are sophisticated signaling hubs whose function depends on membrane integrity. A breach of this barrier, known as lysosomal membrane permeabilization, triggers inflammation and cell death, driving pathologies from lysosomal storage disorders to neurodegeneration. Cells counter membrane damage with diverse repair mechanisms, including endosomal sorting complexes required for transport machinery, sphingomyelin scrambling, annexin-mediated scaffolding, lipid transport, and stress granule plugging. This diversity suggests singular strategies are insufficient, posing an 'orchestration challenge' regarding precise initiation, spatial organization, and temporal coordination. This opinion article proposes that biomolecular condensation, initiated by damage cues, acts as a primary organizing principle. We suggest lysosomal injury nucleates de novo 'repair condensates' that stabilize compromised membranes and serve as recruitment and organizational hubs for repair machinery.

ID: 42143042
Title: VCP modulation ameliorates pathological features in C9orf72 models.
Abstract: Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are devastating neurodegenerative diseases linked by similar pathological mechanisms, which, in some familial forms, may be associated with the same genetic alterations. Among them, the most common is the C9ORF72 (C9) mutation. The C9 mutation consists in an aberrant expansion of the hexanucleotide repeat (G4C2)n that leads to the production and accumulation of toxic dipeptide repeat proteins (DPRs). Some of these C9-DPRs contribute to neuronal dysfunction and degeneration through different mechanisms. One of these involves alterations in the protein quality control (PQC) system, specifically in the autophagy-lysosomal pathway. Valosin-containing protein (VCP) is a critical component of the PQC system, assisting the degradation of misfolded proteins and damaged organelles and the maintenance of cellular homeostasis. In this study, we investigated the role of VCP in modulating pathological features associated with C9 mutation. Using neuronal cell models, we demonstrated that VCP overexpression significantly reduced C9-DPRs levels. This reduction is mediated by mechanisms involving both the ubiquitin-proteasome system (UPS) and autophagy. Additionally, we also observed that C9-DPRs induce lysosomal damage, which is counteracted by VCP overexpression, as indicated by decreased galectin-3 puncta and restored lysosomal pH. We then pharmacologically activated VCP-mediated clearance through SMER28, increasing the clearance of the most toxic DPR, the polyPR. We also determined that in this model, SMER28 activity is mediated by the UPS and is associated with the mitigation of DPR-induced lysosome damage. Additionally, using motor neurons derived from induced pluripotent stem cells (iPSC-MNs) from C9-ALS mutation carriers, we demonstrated that SMER28 treatment significantly decreased polyGA levels, a marker for C9-DPR accumulation. Moreover, SMER28 rescued C9-MNs commitment to differentiation and the alteration in the expression of autophagy-related genes. Taken together, our findings strongly support VCP as a modulator of C9 pathology and highlight its potential as a therapeutic target.

ID: 42148083
Title: Ferroptosis-immune crosstalk in CNS diseases: mechanisms and translational insights.
Abstract: Ferroptosis is a form of regulated cell death driven by iron-dependent lipid peroxidation, which plays a pivotal role in regulating the inflammatory-immune microenvironment of central nervous system (CNS) diseases. Mounting evidence indicates that dysregulated iron metabolism and an imbalance in antioxidant defenses can induce ferroptosis in neurons and glial cells while simultaneously remodeling immune cell function, thereby establishing a bidirectional feedback loop that amplifies neuroinflammation and tissue damage. In neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), pro-inflammatory cytokines such as TNF-α and IL-1β released by activated microglia upregulate neuronal iron transporters (e.g., DMT1 and TfR1), promoting iron accumulation and ferroptotic cell death. In turn, damage-associated molecular patterns released from ferroptotic cells further potentiate immune activation, forming a self-amplifying cycle. In contrast, within the glioma microenvironment, CD8+ T cell-derived IFN-γ suppresses SLC7A11 expression in tumor cells, leading to glutathione depletion and glutathione peroxidase 4 inactivation, thereby triggering ferroptosis and modulating anti-tumor immunity. Although targeting ferroptosis or neuroimmune pathways has shown therapeutic promise in mitigating neurological deficits and enhancing anti-tumor responses, the underlying mechanisms governing ferroptosis-immune crosstalk remain inadequately characterized. Herein, this review systematically summarizes the key biological characteristics of ferroptosis and immune responses, with particular emphasis on their interplay across major CNS disorders (i.e., AD, PD, ALS, multiple sclerosis, stroke, and glioma). Furthermore, we discuss emerging therapeutic strategies encompassing small molecules, immunomodulatory approaches, and nanotechnology-based interventions, highlighting the ferroptosis-immune axis as a promising therapeutic target for CNS diseases.

ID: 42155171
Title: Targeting lysosomal dysfunction with small-molecule TRPML1 ligands: Therapeutic opportunities in lysosomal storage disorders, neurodegeneration and beyond.
Abstract: TRPML1, a lysosomal Ca2+ channel, has emerged as a clinically relevant target due to its genetic and mechanistic links to lysosomal storage disorders and neurodegenerative diseases, including Gaucher disease, Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. This evidence has prompted TRPML1 drug discovery efforts across academia and industry, with several small-molecule agonists advancing toward clinical development. In this review, we provide a comprehensive overview of the therapeutic potential of TRPML1 as a molecular target from a medicinal chemistry perspective. We summarize the structural basis of channel activation and inhibition, highlighting insights from recent cryo-EM studies that define the principal ligand-binding sites and mechanisms of allosteric modulation. We systematically survey the chemical space of TRPML1 ligands reported to date, including diverse agonist and antagonist chemotypes, and extend this analysis to encompass undisclosed or recently disclosed compounds emerging from industry pipelines. Furthermore, we discuss key determinants of ligand design and developability, including the challenges associated with targeting a deeply embedded, lipophilic binding pocket within the membrane. Overall, the available evidence positions TRPML1 as a promising target for small-molecule drug discovery and provides a framework for the rational design of next-generation lysosome-directed therapeutics.

ID: 42171198
Title: Targeting lipid nanoparticle mediated co-delivery of edaravone and kaempferol for amyotrophic lateral sclerosis therapy.
Abstract: Amyotrophic lateral sclerosis (ALS) is characterized by a progressive and selective loss of motor neurons in the central nervous system, particularly in the brain and spinal cord. However, the main cellular mechanisms and cell death pathways leading to motor neuron degeneration have not yet been clarified. Research indicates evidence of ferroptosis in ALS, and the natural compound kaempferol has been demonstrated to inhibit neuronal ferroptosis. However, damage to the blood-brain barrier (BBB) prevents the drug from penetrating the central nervous system, which significantly reduces its therapeutic efficacy. Here, we developed a targeted delivery system named Eda/Kae@Lip-RGD (EKLR), which consisted of liposome-grafted RGD peptides for the co-delivery of the drugs kaempferol and edaravone, capable of crossing the BBB to provide co-delivery of kaempferol and edaravone for combined treatment of ALS. As expected, treatment with EKLR for one month significantly slowed down weight loss and improved athletic performance in SOD1G93A transgenic mice. Mechanistically, this nanomedicine suppressed ferroptosis by upregulating the antioxidant proteins GPX4 and SLC7A11, alongside the downregulation of Nrf2 and ACSL4 levels, thus collectively preserving neuronal integrity. Meanwhile, EKLR restored the normal morphology and the survival rate of neurons and maintained the mitochondrial structure and morphological integrity. Accordingly, this nanoplatform may represent a distinctive and potentially effective strategy for achieving neuroprotection in ALS as well as in other disorders of the central nervous system.

ID: 42178983
Title: Protein Disulfide Isomerase Disassembles TDP-43/G3BP1 Condensates and Antagonizes TDP-43 Pathological Aggregates.
Abstract: Cytoplasmic mislocalization and aggregation of transactive response DNA-binding protein-43 (TDP-43) is a common pathological feature of amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration, and Alzheimer's disease with TDP-43 pathology (AD-TDP); the exact role of protein disulfide isomerase (PDI), an enzyme with chaperone activity, in modulating the pathological behavior of TDP-43 is unknown. In this study, we report that wild-type PDI, through its specific interaction with TDP-43, markedly attenuates phase separation of TDP-43, competitively displaces G3BP1 to disassemble TDP-43/G3BP1 condensates, and further counteracts the pathological mislocalization, abnormal phosphorylation, and pathological aggregation of TDP-43 through the b' domain of the enzyme. Ultimately, this alleviates mitochondrial damage and neuronal toxicity caused by TDP-43 aggregation and suppresses UNC13A cryptic splicing in stressed cells. In the presence of abnormal forms of PDI, however, PDI loses its activity, and stress granules containing TDP-43 are assembled into amyloid fibrils, resulting in mitochondrial impairment and neuronal cell death in ALS and AD-TDP patients. These findings not only provide new insights into the pathogenic mechanisms of TDP-43 in neurodegenerative diseases such as ALS and AD-TDP, but also propose PDI as a potential therapeutic target.

ID: 42183611
Title: Mammalian lysophagy: mechanisms and pathophysiological implications.
Abstract: Lysophagy is a form of selective macroautophagy/autophagy that preserves lysosomal integrity by eliminating damaged lysosomes. Lysosomal membrane permeabilization can arise from diverse physiological and pathological insults, including proteotoxic stress, crystalline particles, pathogens and chemical perturbations, and occurs along a continuum ranging from transient nanoscale lesions to catastrophic rupture. Cells respond to lysosomal injury through a hierarchical quality-control network in which membrane repair, lysophagic removal and lysosomal regeneration operate in a coordinated manner. Damage recognition involves sensing of exposed lumenal glycans and membrane lipids, followed by ubiquitin-dependent tagging that recruits selective autophagy receptors and activates the core autophagy machinery to form lysophagosomes. Lysophagy is closely integrated with membrane repair pathways, metabolic signaling and innate immune responses that together determine lysosomal fate. Dysregulated lysosomal quality control has been implicated in diverse diseases, including neurodegeneration, infection, cancer and chronic inflammatory disorders. In this review, we summarize current mechanistic insights and emerging experimental approaches for studying lysosomal quality control and lysophagy in mammalian cells.Abbreviations: ALR, autophagic lysosome reformation; ALS, amyotrophic lateral sclerosis; ATG8, mammalian Atg8-family protein; ER, endoplasmic reticulum; ESCRT, endosomal sorting complexes required for transport; LAMPs, lysosome associated membrane proteins; LIR, LC3-interacting region; LLOMe, L-leucyl-L-leucine methyl ester; LMP, lysosomal membrane permeabilization; PITT, phosphoinositide-initiated membrane tethering and lipid transport; PtdIns3K, class III phosphatidylinositol 3-kinase; PtdIns3P, phosphatidylinositol-3-phosphate; PtdIns4P, phosphatidylinositol-4-phosphate; ROS, reactive oxygen species; V-ATPase, vacuolar-type H+ -ATPase.

ID: 42212756
Title: 5-Hydroxytryptamine Distribution Alteration in Both Neuron and Synapse of Tg(SOD1*G93A)1gur Mice: A Potential Intervention Candidate Strategy for Amyotrophic Lateral Sclerosis.
Abstract: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease; the precise pathogenesis of sporadic ALS (sALS) has not yet been elucidated up to now. Previous studies revealed that the abnormal alterations of some non-motor neurons (non-MN) were a potential pathogenesis of sALS. Therefore, this study aims to search the potential evidences of non-MN in the pathogenesis of ALS via exploring potential relationships between 5-hydroxytryptamine (5-HT) neurons and the development of ALS. We employed fluorescent immunohistochemistry to investigate the altered distribution patterns of 5-HT and tryptophan hydroxylase 2 in the spinal cord and brainstem of Tg(SOD1*G93A)1Gur (TG) and wild-type (WT) mice. Additionally, we used western blot to analyze the expression levels of 5-hydroxytryptamine receptor 1A (5-HTR1A) and 5-HTR2A. Our findings revealed that 5-HT synapses were primarily distributed in the funiculus lateralis, anterior horn, posterior horn, central lateral column, and the area around the central canal of cervical, thoracic, and lumbar segments, and raphe nucleus as well as lateral paragigantocellular nucleus, and gradually reduced following age increase in WT mice. However, 5-HT synapses in the spinal cord and 5-HT neurons in the brainstem gradually increased following the progression of disease and presented a significantly negative correlation between the increased distribution of 5-HT synapses and neurons and the reduction of neural cell number (positively correlated with the increase in neural cell death) at the onset and/or progression stage of TG mice. 5-HTR1A significantly increased, while 5-HTR2A significantly decreased at the onset stage of TG mice. Our study speculated that the distribution changes of 5-HT synapses in the spinal cord and 5-HT neurons in the brainstem play a potential protective role in the pathogenesis of sALS through a compensatory 5-HT increase.

ID: 42227472
Title: Fisetin and Neurodegeneration: From Preclinical Studies to Potential Clinical Applications.
Abstract: Neurodegenerative diseases (NDs), like Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and multiple sclerosis, pose significant challenges due to their gradual deterioration and limited available treatments. Fisetin, a naturally occurring flavonoid, has gained attention for its neuroprotective properties. This review explores the therapeutic potential of fisetin in NDs, focusing on its molecular processes and signaling pathways. Additionally, fisetin exhibits significant protective properties, particularly in reducing oxidative stress, neuroinflammation, and apoptosis. It enhances neuronal survival and reduces neuroinflammation by regulating key pathways, such as Nrf2/ARE, PI3K/Akt, and NF-κB. It also has anti-inflammatory, anti-apoptotic, and antioxidant actions. It stimulates autophagic processes, aiding in the removal of harmful protein aggregates, like tau tangles and amyloid plaques, which are hallmarks of NDs. Fisetin, as demonstrated through behavioral evaluations in animal models, has been found to improve motor coordination, synaptic plasticity, and cognitive function. Furthermore, fisetin's potential as a neuroprotective drug is emphasized by its role in enhancing autophagy and reducing tau and amyloid pathology. Research has shown its efficacy in enhancing neural resilience, synaptic plasticity, and cognitive function in both preclinical and in vitro settings. However, clinical translation remains limited due to challenges in pharmacokinetics and bioavailability, despite robust experimental evidence. Further clinical trials are needed to evaluate the safety and efficacy of fisetin, especially in early-stage NDs, explore potential synergistic effects, and understand the molecular interactions. The review demonstrates fisetin's therapeutic potential, recent research, and future strategies for NDs, highlighting bioavailability limitations and the need for new formulations or delivery systems.

ID: 42236747
Title: Targeting mitophagy for neuroprotection: mechanisms and therapeutic opportunities.
Abstract: Mitochondria are essential for neuronal energy production, cellular homeostasis, and overall neuronal function. Due to their high metabolic demands and limited regenerative capacity, neurons are particularly vulnerable to mitochondrial dysfunction, which leads to ATP depletion, excessive reactive oxygen species (ROS) production, and calcium imbalance-ultimately causing oxidative stress, metabolic disruption, and neuronal death. Mitophagy is a selective process that removes damaged mitochondria through the autophagy-lysosome pathway. As a key mechanism of mitochondrial quality control, mitophagy preserves energy production, limits oxidative damage, and maintains mitochondrial network integrity. This process is regulated by pathways such as PINK1-Parkin and receptor-mediated mechanisms involving BNIP3 and FUNDC1, all of which help sustain cellular health by preventing mitochondrial dysfunction. Impaired mitophagy is a common feature of several neurodegenerative diseases, including Alzheimer's, Parkinson's, amyotrophic lateral sclerosis (ALS), and Huntington's disease, exacerbating mitochondrial damage and neuronal stress. Emerging therapeutic strategies that target mitophagy-ranging from pharmacological agents and gene therapies to dietary interventions-show promise in restoring mitochondrial quality and protecting neurons from degeneration. Nevertheless, challenges remain in translating these findings into effective clinical treatments. Mitophagy represents a critical mechanism for preserving neuronal integrity and offers a compelling target for innovative therapies against neurodegenerative disorders.

ID: 42243993
Title: Hyperoside protects against poly-GR-mediated neurodegeneration via regulation of mitochondrial fission and oxidative stress in C9orf72-associated ALS.
Abstract: Arginine-rich poly-glycine-arginine (poly-GR), a toxic dipeptide repeat protein generated from C9orf72 hexanucleotide repeat expansion, drives mitochondrial dysfunction, oxidative stress, and neuronal loss in amyotrophic lateral sclerosis (ALS). Hyperoside, a bioactive flavonoid, exhibits antioxidant and cytoprotective properties, but its therapeutic relevance to C9orf72-associated ALS remains unclear. To determine whether hyperoside attenuates poly-GR-induced mitochondrial and oxidative injury and improves neuronal survival in cellular and animal models of C9orf72-ALS. A combined in vitro and in vivo experimental study using motor neuron-like cells and an AAV-mediated neonatal mouse model of poly-GR toxicity. NSC34 cells expressing EGFP-GR50 were analyzed for mitochondrial morphology, membrane potential, ROS generation, antioxidant signaling, and apoptosis using confocal microscopy, CellROX/MitoTracker assays, Western blot analysis, and viability testing. For in vivo assessment, neonatal mice received intracerebroventricular AAV9-EGFP-GR50 followed by intraperitoneal hyperoside (10 mg/kg). Survival, cerebral hemisphere length, and cortical NeuN⁺ neuron numbers were quantified. Poly-GR expression induced pronounced mitochondrial fragmentation, reduced membrane potential, elevated ROS, and suppressed Nrf2/HO-1/GPx4 signaling, accompanied by increased Drp1 and reduced Opa1 expression. Hyperoside reversed these abnormalities by restoring mitochondrial integrity, normalizing the Drp1/Opa1 balance, enhancing Nrf2 nuclear accumulation, and increasing the expression of HO-1 and GPx4. Hyperoside also reduced cleaved caspase-3 and corrected the Bax/Bcl-2 ratio, improving cell viability under basal and oxidative stress conditions. In vivo, hyperoside modestly prolonged survival, increased cerebral hemisphere length, and significantly preserved cortical neuronal numbers in AAV9-EGFP-GR50 mice. Hyperoside mitigates poly-GR-induced neurotoxicity by alleviating excessive mitochondrial fission, strengthening Nrf2-dependent antioxidant defenses, and suppressing apoptosis. These findings support hyperoside as a promising multi-target therapeutic candidate for C9orf72-associated ALS.

ID: 42274592
Title: The Role of Iron in Neuronal Homeostasis: A Double-Edged Sword.
Abstract: Iron is an essential micronutrient that plays a central role in numerous biological processes. Despite its relatively low abundance in the human body, iron is particularly critical for brain function. Systemic and cerebral iron homeostasis is tightly regulated through coordinated mechanisms involving absorption, transport, storage, and recycling. Within the brain, iron metabolism is further controlled by the blood-brain barrier and specialized neural cell populations, including neurons, astrocytes, oligodendrocytes, and microglia. Iron is indispensable for neurodevelopment, supporting neurogenesis, myelination, and neurotransmitter synthesis. However, both iron deficiency and iron overload have detrimental consequences. Early-life iron deficiency disrupts neural development and leads to long-lasting cognitive, motor, and behavioral impairments, whereas excessive iron accumulation promotes oxidative stress, ferroptosis, and neuroinflammation. These mechanisms have been described to contribute to the pathogenesis of major neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, neurodegeneration with brain iron accumulation, and amyotrophic lateral sclerosis. This review first outlines systemic and brain iron metabolism, highlighting how neural cells regulate homeostasis. Next, it examines iron's physiological roles, particularly in neurogenesis and neurodevelopment. Finally, it explores iron's involvement in neurodegenerative diseases, emphasizing neuroinflammation as a primary mechanism of iron toxicity.

ID: 42302791
Title: ZNF512B safeguards genome integrity at regulatory regions to repress the SASP and inflammation.
Abstract: Cellular senescence drives aging and disease largely through the senescence-associated secretory phenotype (SASP), yet its regulatory mechanisms remain unclear. Using a SASP reporter combined with a CRISPR-Cas9 screen targeting active regulatory elements, we identify the zinc-finger protein ZNF512B as a key suppressor of the SASP. ZNF512B loss induces DNA damage, activates cGAS-STING signaling, and triggers inflammatory transcriptional reprogramming. In contrast, ZNF512B promotes preferential DNA repair at regulatory genomic regions, limiting SASP induction. Mechanistically, ZNF512B is rapidly recruited to DNA-damage sites via distinct zinc-finger domains and facilitates NuRD complex targeting to damaged chromatin, enabling precise repair. In human neuromuscular organoids, ZNF512B deficiency induces inflammation, lineage imbalance, and cytokine secretion resembling amyotrophic lateral sclerosis (ALS)-associated pathology. In vivo, ZNF512B overexpression reduces DNA damage and inflammation following acute liver injury. Together, these findings support a mechanism of preferential DNA repair that contributes to maintaining genome integrity, suppressing SASP and inflammation.

ID: 42327061
Title: Lipid transfer protein ORP3 mediates lysosomal repair via LC3B and ubiquitin-TAK1-p38 signaling.
Abstract: Lysosomal membrane damage triggers a multi-stage repair response essential for cellular homeostasis. Here we identify the oxysterol-binding protein-related protein ORP3 as a critical mediator of late-stage lysosomal membrane repair. Following lysosomal damage induced by L-leucine-leucine methyl ester (LLOME) or cationic amphiphilic drugs (CADs), ORP3 is phosphorylated and recruited to ER-lysophagosome contact sites via a signaling cascade initiated by lysosomal membrane ubiquitination, TAK1, p38 MAPK, and, to a lesser extent, IKK. p38-dependent phosphorylation promotes direct interaction between ORP3 and LC3B, which together with PI(4,5)P₂ binding, is required for autophagic lysosome recruitment. ORP3 depletion impairs late-stage lysosomal recovery, elevates lysosomal lipid peroxidation, and reduces cell survival. A lipid transfer-deficient ORP3 mutant fails to restore lysosome function despite normal recruitment, indicating that ER-to-lysophagosome transfer of phosphatidylcholine by ORP3 is functionally required. ORP3 activity is subsequently terminated by VCP/p97-mediated deubiquitination of lysosomes. These findings define ORP3 as a MAPK regulated lipid transfer protein during the late autophagic phase of the endolysosomal damage response. Lysosomal membrane damage triggers ubiquitination that activates a TAK1-p38 signaling cascade, phosphorylating the lipid transfer protein ORP3 and recruiting it to damaged lysosomes via LC3B interaction. ORP3-mediated phosphatidylcholine transfer from the ER is essential for late-stage lysosomal repair and cell survival.

ID: 42349421
Title: Rewiring ALS by modulating the autophagy receptor SQSTM1.
Abstract: Drug screening for genetic disorders is limited by difficulty identifying disease-relevant phenotypes. In this issue, Roussange et al., show that reverse phenotypic mapping could uncover therapeutic gene expression signatures. Using this approach, they identified prazosin, which increases SQSTM1 expression and rescues disease phenotypes in iPSC-derived motor neurons and zebrafish model of amyotrophic lateral sclerosis with SQSTM1 haploinsufficiency.

ID: 42350373
Title: Karyoptosis mediates cell death and neurodegeneration upon proteotoxic stress.
Abstract: Neurodegenerative diseases are frequently associated with proteotoxic stress linked to disease specific proteins. The autophagy-lysosome system provides essential control of proteotoxic stress and its failure can lead to initiation of apoptosis. However, in aging and neurodegenerative diseases apoptosis is insufficient to account for all neuronal death, and several different cell death types have been reported in these contexts. Here we show that karyoptosis, a distinct form of cell death, can be induced by proteotoxic stress and then develops through nuclear degeneration and cellular expulsion of nuclear material. We establish that karyoptosis is regulated by the p38 kinase signalling pathway, which controls stability of the nuclear lamina protein LaminB1 via direct phosphorylation. We demonstrate that karyoptosis affects neurons in models of amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) pathology. Finally, we identify karyoptotic features in post-mortem frontal cortex of FTD and Alzheimer's disease (AD) patients. Together these findings characterise a form of cell death directly linked to proteotoxic stress and nuclear lamina stability that is associated with neurodegeneration.

ID: 42353250
Title: Microglial Dysfunction Induced by C9ORF72 Dipeptide Repeat Proteins: Biomarker and Therapeutic Perspectives.
Abstract: The GGGGCC hexanucleotide repeat expansion (HRE) in C9ORF72 was recognized as the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Repeat-associated non-AUG (RAN) translation of the expanded repeat generated dipeptide repeat proteins (DPRs), which disrupted multiple cellular processes and contributed to neurodegeneration. Emerging evidence indicated that disease pathogenesis involved both gain-of-function (GOF) and loss-of-function (LOF) mechanisms. DPR-mediated GOF toxicity induced ribosomal dysfunction, nucleolar stress, proteostatic impairment, and neuronal injury, whereas C9ORF72 LOF disrupted lysosomal and autophagic pathways in microglia, impairing the immune homeostasis. Neuronal injury further promoted the release of damage-associated signals that triggered secondary microglial activations and chronic neuroinflammations. This review summarized current knowledge of DPR biology, microglial dysfunction, and their contributions to disease progression in C9ORF72-associated ALS/FTD. Therapeutic strategies targeting repeated RNA, DPR productions, proteostasis, autophagy, and neuroinflammatory pathways were also discussed. In addition, the potentials of fluid biomarkers, including cerebrospinal fluid poly (GP) and blood neurofilament light chain (NfL), for diagnosis, disease monitoring, and therapeutic assessment were shown. Together, these findings provided important insights into disease mechanisms and potential avenues for improved clinical management.

ID: 42365390
Title: Lysophagy protects against ANXA11 amyloid fibril toxicity and propagation in FTLD.
Abstract: Accumulation of Annexin A11 (ANXA11) aggregates is a distinct pathological hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). While genetic studies have linked ANXA11 mutations (e.g., D40G) to disease, the precise molecular events converting aggregation into neurotoxicity and intercellular propagation remain elusive. We hypothesize that lysosomal integrity serves as a critical checkpoint in ANXA11 proteinopathy and that its failure drives disease progression. To model the human pathology of ANXA11, we generated pre-formed fibrils (PFFs) of wild-type and FTLD/ALS-linked D40G mutant ANXA11. Human iPSC-derived neurons, 3D cerebral organoids, and bulk RNA-sequencing were employed to investigate neurotoxicity. High-resolution imaging, lentiviral knockdown, and biochemical assays were performed to delineate the lysosomal damage response and the subsequent "prion-like" spreading of aggregates. The internalized ANXA11 fibrils accumulated in lysosomes, triggering lysosomal membrane permeabilization (LMP). The D40G mutation exacerbated this toxicity, leading to severe LMP, mitochondrial depolarization, and specific transcriptional downregulation of the dynactin subunit ACTR10. Mechanistically, we identified a protective signaling axis involving p38 MAPK, MK2, and HSP27 that senses ANXA11-induced lysosomal damage and initiates lysophagy. Notably, in human cerebral organoids, failure of this lysophagic clearance facilitated the cytoplasmic escape of ANXA11, thereby accelerating its seeding activity and propagation to neighboring cells. Pharmacological or genetic modulation of this pathway significantly altered neuronal survival. Our study established lysosomal rupture as a primary driver of ANXA11-associated neurodegeneration and validated the p38/MK2/HSP27 axis as a crucial defense mechanism in human neural tissue. These findings provide a novel mechanistic link between lysosomal quality control and ANXA11 propagation, highlighting that enhancing lysophagic flux represents a promising translational strategy to halt the progression of FTLD and ALS.

ID: 42419281
Title: Sealing and healing: A two-step model for plasma membrane repair.
Abstract: Plasma membrane damage can cause cell death and is associated with neurodegeneration. In this issue of Developmental Cell, Heffner et al. show that annexin A11 (ANXA11) first plugs membrane lesions, before ESCRT-III is recruited to extrude the damaged patch-a two-step repair mechanism compromised by ALS- and FTD-linked mutations.

ID: 42426573
Title: TSR and peroxidase genes confer resistance to fenoxaprop-P-ethyl and mesosulfuron-methyl in Alopecurus aequalis.
Abstract: Alopecurus aequalis poses severe threat to global wheat production due to evolving resistance to acetyl-CoA carboxylase (ACCase)- and acetolactate synthase (ALS)-inhibiting herbicides. In this study, the resistance mechanisms of a field-evolved resistant population (R) were systematically investigated using dose-response bioassays, target-site gene sequencing, inhibitor assays, antioxidant enzyme activity measurements, RNA sequencing (RNA-seq), quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and yeast functional validation. Dose-response results revealed that the R population exhibited moderate resistance to fenoxaprop-P-ethyl (RI = 9.58) and low-level resistance to mesosulfuron-methyl (RI = 3.07). Cross-resistance testing indicated that the R population was resistant to other ACCase-inhibiting herbicides (haloxyfop-P-methyl, clodinafop-propargyl, clethodim, and pinoxaden) and the ALS-inhibiting herbicide rimsulfuron. Target-site sequence analysis identified two mutations in the R population: Ile-1781-Leu (ACCase) and Pro-197-Ser (ALS1). Pretreatment with the cytochrome P450 and GST inhibitor did not reverse resistance to fenoxaprop-P-ethyl or mesosulfuron-methyl. Compared to the susceptible (S) population, the R population had significantly lower H2O2 content and higher activities of peroxidase (POD) and catalase (CAT), indicating an enhanced reactive oxygen species (ROS) scavenging capacity. RNA-seq and qRT-PCR analyses identified three POD-annotated contigs (PODSPC4, POD12-1, POD12-2) that were upregulated in the R population. Yeast heterologous expression validated that AaPOD12-1 and AaPOD12-2 significantly increased yeast resistance to fenoxaprop-P-ethyl and mesosulfuron-methyl. These results demonstrate that resistance in the R population is co-mediated by target-site mutations and non-target-site resistance involving enhanced ROS scavenging, with AaPOD12-1 and AaPOD12-2 representing the first functionally characterized antioxidant enzyme genes associated with herbicide resistance in A. aequalis. © 2026 Society of Chemical Industry.

ID: 42442908
Title: Role of ESCRT pathway and autophagy in neurodegenerative diseases.
Abstract: Neurodegenerative diseases are characterized by progressive neuronal dysfunction and loss resulting from impaired proteostasis and vesicular trafficking. Neurons are particularly vulnerable to these processes due to their post-mitotic nature and complex architecture. Autophagy and the endolysosomal system constitute the primary degradative pathways responsible for maintaining neuronal homeostasis. However, increasing evidence indicates that their effective function critically depends on coordination with the endosomal sorting complexes required for transport (ESCRT). Beyond their canonical role in multivesicular body biogenesis and membrane scission, ESCRT components are now recognized as essential regulators of autophagosome closure, amphisome formation, autophagosome-lysosome fusion, and endolysosomal membrane repair. Disruption of this ESCRT-autophagy interface has emerged as a common pathological feature across major neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis/frontotemporal dementia. This review synthesizes evidence from genetic, biochemical, and neuropathological studies to highlight shared molecular nodes, such as ESCRT-III components, the VPS4 ATPase, the adaptor protein ALIX, and late endosomal regulators, including Rab7, that couple membrane remodeling to autophagic flux. Failure of these regulatory checkpoints destabilizes endolysosomal integrity, arrests autophagic maturation, and promotes the accumulation of toxic protein species, thereby driving progressive neuronal degeneration. By framing neurodegeneration through the lens of ESCRT-autophagy coupling failure, this review provides a unified mechanistic perspective that links diverse pathogenic proteins to shared cellular vulnerabilities and identifies ESCRT-mediated membrane dynamics as a critical determinant of neuronal survival.

ID: 42451124
Title: Neuroprotective Effects of Sorghum Polyphenol in Alzheimer's Disease: In Vitro and In Silico Analyses.
Abstract: Accumulation of amyloid-beta (Aβ) senile plaques in the human brain is a major hallmark of Alzheimer's disease (AD), which manifests as progressive decline in memory and cognitive functions and currently lacks effective disease-modifying therapies. Emerging evidence demonstrates that polyphenol-rich plant foods are potential complementary therapies for AD. In this study, we investigated crude polyphenol extracts (CPEs) and purified polyphenol extracts (PPEs) from three sorghum genotypes for their ability to inhibit Aβ42-induced toxicity in MC-65 cells. Thioflavin T fluorescence, cell viability, mitochondrial function, oxidative stress assays, and Western blotting, along with RNA sequencing and computational analyses, were used to characterise both functional and transcriptomic responses of the cells to polyphenol treatments. CPEs and PPEs inhibited Aβ42 aggregation by 67-76% and significantly reduced Aβ oligomer species. The extracts increased cell viability against Aβ-induced toxicity by more than 70%, decreased intracellular oxidative stress, and enhanced mitochondrial activity by over 80%. Transcriptomic profiling revealed differential modulation of genes associated with ferroptosis and MAPK/NF- κB signalling pathways, indicating regulation of inflammatory and oxidative-stress responses are mechanisms underlying the observed neuroprotection. This study demonstrates that polyphenol extracts from black and red sorghum genotypes exert strong multitarget neuroprotection against Aβ42 toxicity in MC-65 cells. These findings support further evaluation of sorghum-derived polyphenols as complementary therapeutic candidates for AD, with in vivo studies required to establish efficacy and translational potential.

ID: 42451740
Title: Lysosomes in Ferroptosis: Regulatory Mechanisms and Molecular Targets.
Abstract: Ferroptosis is a regulated form of cell death characterized by iron-dependent lipid peroxidation and membrane damage, with broad relevance to human disease. Accumulating evidence suggests that ferroptosis is governed by coordinated organelle-level regulation, among which lysosomes have emerged as central hubs. By controlling endolysosomal iron processing, transport, and degradation pathways, lysosomes shape the intracellular distribution and reactivity of iron, thereby modulating iron-driven lipid peroxidation. The acidic, iron-rich microenvironment and limited local antioxidant capacity render lysosomal membranes highly susceptible to oxidative injury, positioning lysosomes as initiation and amplification sites of lipid peroxidation. Meanwhile, lysosome-dependent selective autophagy pathways actively remodel iron homeostasis, lipid metabolism, and cellular antioxidant defenses, thereby dynamically modulating ferroptotic sensitivity. Mitochondria-lysosome crosstalk further redistributes iron, reactive oxygen species, and lipid substrates, linking lysosomal activity to interorganelle control of ferroptosis. Lysosomal stress-responsive signaling also coordinates metabolic adaptation and redox control. This review summarizes and integrates current evidence on lysosome-centered mechanisms that organize iron metabolism, lipid peroxidation, selective autophagy, organelle crosstalk, and stress-responsive signaling during ferroptosis, and further discusses their disease-specific roles, therapeutic potential, and translational challenges.

ID: 42459050
Title: Notoginsenoside R1 Alleviates Acetaminophen-Induced Liver Injury via MAPK/mTOR-Mediated Autophagy.
Abstract: Acetaminophen (APAP) overdose is a leading cause of acute liver injury (ALI), yet effective therapeutic options remain limited. Although notoginsenoside R1 (NGR1) is a major bioactive saponin isolated from Panax notoginseng with established anti-inflammatory and anti-oxidant properties, its hepatoprotective potential and underlying mechanisms in APAP-induced liver injury (AILI) have not been systematically investigated. In this study, we established an AILI mouse model and evaluated the protective effects of NGR1 through biochemical assays, histopathology, Western blotting, and immunofluorescence, complemented by integrative transcriptomic, metabolomic, and gut microbiota analyses. Mechanistic involvement of the MAPK/mTOR-autophagy pathway was further validated using L-leucine as a pharmacological activator of mTOR. NGR1 markedly attenuated AILI, as reflected by reduced serum ALT/AST levels, improved hepatic histology, and increased survival in acute liver failure. NGR1 suppressed inflammatory responses by decreasing IL-1[Formula: see text], IL-6, and TNF-[Formula: see text] levels and alleviated oxidative stress by restoring GSH and SOD while reducing MPO, ROS, and MDA accumulation. Multi-omics analysis revealed significant enrichment of MAPK/mTOR signaling, autophagy, ferroptosis, and glutathione metabolism pathways. Mechanistically, NGR1 promoted autophagic flux (increased LC3-II/I, ATG5, and ATG7 with decreased p62), inhibited ferroptosis (upregulation of GPX4 and SLC7A11 with downregulation of ACSL4), and suppressed APAP-induced activation of the MAPK/mTOR pathway. Pharmacological activation of mTOR by L-leucine partly abolished the protective effects of NGR1, reversing autophagy activation and restoring inflammatory and oxidative injury. These findings collectively demonstrate that NGR1 protects against AILI by inhibiting MAPK/mTOR signaling, restoring autophagy, and suppressing ferroptosis, highlighting NGR1 as a promising therapeutic candidate for APAP-induced hepatotoxicity.

ID: 42461471
Title: METTL3-mediated N6-methyladenosine modification of circHUWE1 promotes high glucose-induced cardiomyocyte apoptosis and ferroptosis-related alterations through regulating miR-671-5p/CELF1 axis.
Abstract: Diabetic cardiomyopathy (DCM) is a prevalent diabetes-related cardiac complication. miR-671-5p has been shown to mitigate ischemia-reperfusion-induced cardiomyocyte injury. This study investigated the role and underlying mechanisms of miR-671-5p in a DCM cell model established by exposing AC16 cardiomyocytes to high glucose (HG). The miRNA expression dataset GSE210036 from diabetic mouse hearts was analyzed. Cell injury was evaluated by assessing cell viability, apoptosis, and ferroptosis-related alterations. The expression levels and interactions of miR-671-5p, circHUWE1, and CELF1 were examined in the cell model. p38 MAPK activation was further assessed following modulation of the circHUWE1/miR-671-5p/CELF1 axis. Additionally, the m6A modification of circHUWE1 was evaluated. Bioinformatics analysis revealed decreased miR-671-5p expression in diabetic mouse hearts compared to healthy controls. HG treatment downregulated miR-671-5p expression and upregulated the levels of circHUWE1 and CELF1. circHUWE1 upregulation resulted from diminished METTL3-dependent m6A modification. Both miR-671-5p mimic and circHUWE1 knockdown attenuated HG-induced apoptosis and ferroptosis-related alterations. Mechanistically, circHUWE1 elevated CELF1 expression and subsequently activated p38 MAPK by sponging miR-671-5p. The cardioprotective effects of dexmedetomidine (Dex) are associated with the circHUWE1/miR-671-5p/CELF1 axis. In conclusion, the circHUWE1/miR-671-5p/CELF1 axis regulates HG-induced cardiomyocyte apoptosis and ferroptosis-related alterations and represents a novel mechanism underlying Dex-mediated cardioprotection.

ID: 42469634
Title: Secretory leukocyte protease inhibitor (SLPI) attenuates TLR4/NF-κB-mediated neuroinflammation in amyotrophic lateral sclerosis: a candidate molecule associated with neuro-pathology.
Abstract: Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disorder driven by neuroinflammation involving activated microglia and astrocytes, which accelerates the loss of motor neurons. While Secretory leukocyte protease inhibitor (SLPI) is known for its immunomodulatory properties, its specific role in ALS pathogenesis has not been fully established. This study aimed to characterize the expression patterns and functional significance of SLPI in ALS models. The study utilized SOD1G93A mice to analyze the spatiotemporal dynamics of SLPI expression in the gastrocnemius muscle, lumbar spinal cord, and serum across different disease stages. In vitro functional assays were conducted using siRNA-mediated knockdown of SLPI in BV2 (microglia), MA (astrocytes), and NSC-34 (motor neurons) cell lines. Additionally, recombinant SLPI protein was applied to LPS-stimulated BV2 cells to investigate its effect on the TLR4/ NF-κB signaling pathway. In SOD1G93A mice, SLPI was significantly upregulated in the gastrocnemius muscle from the pre-symptomatic stage (60 days) through the late stage (130 days). In the lumbar spinal cord, SLPI showed a transient initial increase but declined sharply by the end-stage; a similar significant reduction was observed in late-stage serum levels. In vitro, SLPI knockdown exacerbated pro-inflammatory cytokine production in all three cell types and impaired the antioxidant capacity of NSC-34 motor neurons. Mechanistically, recombinant SLPI attenuated inflammation in BV2 cells by modulating the TLR4/NF-κB pathway. The dynamic changes in SLPI levels suggest its potential relevance as a candidate molecule for disease staging. Meanwhile, its protective effects in regulating inflammation suggest that it could be a promising therapeutic candidate for mitigating ALS-associated neuroinflammation.

ID: 42485981
Title: Cell death mechanisms in sepsis-associated adaptive immune dysfunction.
Abstract: Sepsis remains a leading cause of death, driven not only by early hyperinflammation but also by a catastrophic collapse of adaptive immunity during the late phase. This failure is orchestrated by distinct regulated cell death (RCD) pathways - apoptosis, pyroptosis, necroptosis and ferroptosis - that differentially deplete T cells, B cells and dendritic cells while shaping the immunological milieu. Apoptosis silently eliminates lymphocytes and promotes immunosuppression; pyroptosis and necroptosis release damage-associated molecular patterns, fueling inflammation that paradoxically destroys adaptive effectors; and ferroptosis, an iron-dependent lipid peroxidation process, selectively targets metabolically active CD8+ and T helper cells. This review proposes that these pathways do not operate in isolation but converge on a "cell death decision network" centred on caspase-8, receptor-interacting serine/threonine-protein kinase 1(RIPK1), reactive oxygen species (ROS) and mitochondria, whose integration determines lymphocyte fate under septic stress. Understanding this network opens opportunities for precision immunotherapy. Emerging strategies targeting these pathways hold promise, but their success will require phase-specific application, biomarker-guided patient stratification and cell-type-selective delivery. Targeting the quality, as well as the quantity, of cell death may restore adaptive immunity and improve survival in sepsis.

ID: 42488558
Title: Nucleophosmin 1 proteins as potential therapeutic targets in non-communicable chronic inflammatory diseases: a review of pathophysiological mechanisms.
Abstract: Nucleophosmin1 (NPM1) proteins, initially recognized as central guardians of nucleolar architecture and function, have recently been redefined as pivotal hubs that integrate diverse forms of chronic cellular stress signaling. Although the roles of NPM1 have been extensively elucidated in tumor biology, its broad involvement in non-communicable chronic inflammatory diseases (NCDs) remains insufficiently and unsystematically summarized. Here, we highlight NPM1 as a key sensor of stress-induced nucleolar disassembly, nucleocytoplasmic translocation, and p53 stabilization. In pathological conditions such as myocardial ischemia, endothelial dysfunction, atherosclerosis, and chemotherapy-associated cardiotoxicity, NPM1 exhibits pronounced context dependence functioning either to initiate cytoprotective responses or to promote inflammation and apoptosis. In parallel, NPM1 plays a central role in maintaining genomic stability by sequestering, mobilizing, and regulating essential enzymes across multiple DNA damage repair pathways, including base excision repair (BER) and translesion synthesis (TLS). Dysregulation of these functions is closely linked to chronic pathological processes driven by metabolic stress, oxidative stress, and proteotoxicity. Collectively, available evidence suggests that NPM1, as a core node of the nucleolus-nucleoplasm signaling axis, may constitute a common molecular pathological basis underlying multiple chronic inflammatory diseases, including cancer, cardiovascular diseases, diabetes, and neurodegenerative disorders. A deeper dissection of its post-translational modifications, stress-dependent subcellular re-localization, and interactions with partner proteins is expected to provide a novel conceptual framework and therapeutic avenues for the development of NPM1-based targeted interventions. Accordingly, this review synthesizes the core molecular mechanisms of the NPM1 in the maintenance of cellular homeostasis, including regulating nucleolar stress, DNA damage repair, and inflammation, We place a particular emphasis on how these baseline pathways translate into distinct functional phenotypes within the pathological processes of chronic diseases, including cardiovascular, metabolic, and neurodegenerative disorders.

ID: 42489267
Title: A Blood-Derived Factor Rescues ALS: Platelet Factor 4 Activates OPTN-Dependent Autophagy to Clear SOD1 Aggregates Independently of PINK1.
Abstract: Peripheral factors that systemically regulate amyotrophic lateral sclerosis (ALS) have remained elusive-until now. Here, by integrating population-scale epidemiology with mechanistic dissection, we identify platelet factor 4 (PF4) as the central driver of a circulating neuroprotective axis that restores proteostasis and rescues ALS. In a prospective cohort of >500 000 UK Biobank participants, platelet indices were strongly associated with ALS risk, and serum PF4 levels were significantly reduced in ALS patients. Systemic administration of recombinant PF4 in hSOD1G93A mice produced dramatic therapeutic effects: extended survival, preserved motor function, attenuated neuroinflammation, and reduced neuromuscular junction denervation. Remarkably, this efficacy appears pathology-selective-robust in SOD1-driven models but shows no observable effect in TDP-43 or C9orf72 ALS models. Mechanistically, PF4 achieves what few molecules can: it engages the cell surface receptor LRP1 to activate the TBK1-OPTN signaling axis, restoring impaired autophagic flux through a PINK1/Parkin-independent pathway requiring ATG7, establishing a previously unrecognized peripheral platelet-autophagy-neuron axis that facilitates the co-clearance of pathological SOD1 aggregates and damaged mitochondria. This study unveils PF4 as a first-in-class circulating autophagy regulator with therapeutic potential in ALS. Beyond identifying a candidate biomarker and drug lead, it reveals that systemic factors can directly engage central proteostatic machinery-opening a new frontier for ALS therapy.

ID: 42490384
Title: HUWE1 targets mitochondria via RMC1 to promote neurodevelopment.
Abstract: The HECT-type E3 ubiquitin ligase HUWE1 is a critical regulator of protein homeostasis, genome stability, and neurodevelopment. Variants in HUWE1 are linked to X-linked intellectual disability (XLID), yet a significant number of HUWE1 variants are noncatalytic, leaving their disease mechanisms unresolved. Here, we identify an AMBRA1-RMC1-HUWE1 signaling axis that directs HUWE1-mediated ubiquitination to mitochondria to regulate neural development. In zebrafish, noncatalytic HUWE1 variants found in XLID patients (M375I, G660R, and H669Q) recapitulate key neurodevelopmental deficits, including impaired brain growth and motor neuron defects. Global ubiquitin profiling reveals that these variants selectively disrupt the ubiquitination of mitochondrial proteins without affecting nuclear substrates. Mechanistically, AMBRA1 acts as a mitochondrial scaffold that recruits RMC1, enabling HUWE1 localization to mitochondria through direct interaction with RMC1. Disruption of this recruitment by disease-associated HUWE1 variants prevents mitochondrial targeting and impairs mitochondrial substrate ubiquitination. Notably, Urolithin A treatment ameliorates neurodevelopmental phenotypes in HUWE1-deficient zebrafish. Together, our findings define an AMBRA1-organized mitochondrial recruitment pathway in which RMC1 links HUWE1 to mitochondria, explain noncatalytic HUWE1-associated XLID, and suggest mitochondrial quality-control enhancement as a potential therapeutic strategy.

ID: 42490743
Title: A Self-Reinforcing LipoTIDE Nanoplatform That Overcomes Lipid-Buffering Ferroptosis Resistance for Enhanced Cancer Therapy.
Abstract: Lipid metabolic rewiring is a hallmark of malignancy, allowing tumor cells to sequester fatty acids within lipid droplets (LDs) as a protective reservoir that quenches reactive oxygen species (ROS)-driven lipid peroxidation and thereby evades ferroptosis. Although lipophagy selectively degrades LDs to release free fatty acids (FFAs) and remodel lipid homeostasis, leveraging this process to overcome lipid-buffering ferroptosis resistance remains largely unexplored. Here, we report LipoTIDE (Lipophagy-Tuning Induced Death Enhancer), a self-reinforcing nanoplatform that primes lipophagy-primed ferroptosis by coupling precise lipophagy activation with catalytic ROS generation to dismantle LDs-mediated metabolic defenses in tumors. LipoTIDE co-delivers ultrasmall Pt3Co nanoalloys and tamoxifen within a pH-responsive amphiphilic polymer, enabling tumor-targeted disassembly and localized therapeutic amplification. Triggered by the tumor acidity, LipoTIDE releases Pt3Co nanoalloys for multiple catalytic activities and tamoxifen for initiating lipophagy and decreasing pH value, establishing a self-reinforcing loop that sustains lipophagy and ferroptosis. Additionally, FFAs from lipophagy, together with the Pt3Co nanoalloys, resensitize resistant cancer cells to Pt3Co-catalyzed ROS, thereby amplifying ferroptosis. Consequently, LipoTIDE precisely disrupts lipid homeostasis, triggers robust ferroptotic tumor suppression, and exhibits minimal systemic toxicity. These findings establish lipophagy-primed ferroptosis as a generalizable and actionable strategy for dismantling lipid-buffering defenses of tumors.

ID: 42491593
Title: The role of endoplasmic reticulum stress-mediated autophagy in cadmium-induced liver injury in rats.
Abstract: Cadmium (Cd) is a widespread toxicant with high bioaccumulation potential. This study explores the interplay of endoplasmic reticulum stress (ERS), autophagy, and apoptosis in Cd-induced hepatotoxicity, focusing on whether ERS-driven autophagy protects against liver injury. Male SD rats (4 weeks old, n = 24) were acclimatized for 7 days and randomized into four groups receiving CdCl₂ at doses of 0, 0.5, 1, or 2 mg/kg for 14 consecutive days. A second cohort (n = 36) was similarly allocated to six groups: control, Cd, 4-PBA, Cd + 4-PBA, CQ and Cd + CQ. All treatments were administered via daily intraperitoneal injection throughout the study. On day 14, blood and liver tissues were collected for analyses of liver function, hematological parameters, and histopathology. The expression of target factors was analyzed via qRT-PCR and Western blotting. Results indicate that Cd exposure causes liver injury and disordered hepatocyte morphology. ERS markers Grp78 and Caspase-12 and autophagy-related factors Beclin-1, Atg5, P62 and LC3 are upregulated at both mRNA and protein levels. The endoplasmic reticulum-phagy (ER-phagy) receptor FAM134B and the apoptosis effector cleaved Caspase3 are upregulated at the protein level. These findings indicate that Cd induces ERS, UPR activation, autophagy, reticulophagy, and apoptosis. The ERS inhibitor 4-PBA markedly attenuated Cd-induced hepatic injury. Compared with the Cd group, the Cd + 4-PBA group showed decreased serum ALT and AST levels, as well as reduced RBC, WBC, MCH, and MCV counts. At the molecular level, mRNA and protein expression of ER stress markers Grp78, Caspase-12, PERK, eIF2α, ATF4, IRE1α, JNK, and ATF6 were all downregulated. Protein levels of the ER-phagy receptor FAM134B and the apoptosis effector cleaved Caspase-3 were also decreased. The autophagy inhibitor CQ aggravated such injury. Compared with the Cd group, the Cd + CQ group showed increased serum ALT and AST levels, as well as elevated RBC, MCH, and MCV counts. At the protein level, expression of the autophagy-related factors P62 and LC3, and the apoptosis effector cleaved Caspase-3 was significantly increased. These results show that Cd-induced ERS activates autophagy and reticulophagy mainly via the PERK, IRE1α, and ATF6 pathways, and this adaptive response clears autophagic substrates to alleviate hepatocyte damage.

ID: 42492190
Title: From ROS to Cuproptosis: The molecular evolution of copper nanotherapeutics.
Abstract: The renewed interest in copper-based materials for biomedical applications has been catalyzed by advances in nanotechnology, shifting the paradigm from empirical antimicrobial therapies toward multifunctional nanoplatforms capable of targeted intervention and theranostic integration. This work provides a systematic assessment of the developmental trajectory of copper-containing nanostructures-ranging from single-component Cu, CuO, and Cu2O particles to shape-anisotropic architectures, polymer composites, and ultimately bimetallic combinations, with particular emphasis on Cu/Se systems. A central thesis advanced here is that the bioactivity of these agents cannot be attributed to a single intrinsic parameter; rather, it emerges from a convoluted interplay of size, morphology, surface potential, oxidation state, shell composition, and, notably, the aggregation behavior in physiological fluids-the latter being frequently obscured by protein corona artifacts. Moving beyond conventional reactive oxygen species (ROS)-driven oxidative injury and mitochondrial apoptotic cascades, recent molecular toxicology has identified two non-apoptotic, copper-relevant cell death modalities: cuproptosis, characterized by aggregation of lipoylated mitochondrial proteins via the ferredoxin 1 (FDX1), and ferroptosis, involving glutathione peroxidase 4 (GPX4) inhibition and intracellular glutathione exhaustion. These pathways, together with the phenomenon of cuproplasia in malignant cells, offer unprecedented opportunities for selective therapeutic intervention. Among all structural classes, bimetallic Cu/Se nanoparticles represent a "reconciliation of redox opposites," wherein the pro-oxidant Fenton-like activity of copper is counterbalanced by selenium's antioxidant, photothermal (conversion efficiency exceeding 80%), and regulatory functionalities, leading to substantially improved therapeutic indices and diminished off-target effects. Anisotropic configurations-including nanoflowers and nanorods-further enable multimodal diagnostic imaging and combined therapy, yet their clinical translation is constrained by difficulties in morphological reproducibility and in vivo clearance mechanisms. While clinical adoption remains largely confined to topical indications (e.g., CuO-embedded wound dressings that have demonstrated significant reductions in surgical site infections in randomized trials), the emerging mechanistic framework centered on cuproptosis and hypoxia-inducible factor 1α (HIF-1α) modulation positions copper-based nanoplatforms as strong contenders for future theranostic applications. The review concludes that the field must prioritize a "clearance-by-design" philosophy, implement standardized green synthesis protocols, and conduct comprehensive long-term biodistribution and toxicity studies in vivo to close the existing gap between robust preclinical evidence and tangible clinical impact.

ID: 42492261
Title: A water-soluble Dendrobium officinale polysaccharide (DOPW) attenuates hepatic fibrosis via gut microbiota-mediated autophagy activation.
Abstract: Hepatic fibrosis currently lacks effective therapies. DOPW, a water-soluble polysaccharide isolated from Dendrobium officinale, exerts anti-fibrotic effects, but its underlying mechanisms remain unclear. This study investigates whether DOPW attenuates fibrosis through a gut microbiota-dependent mechanism involving key microbial metabolites and the hepatic ERK1/2-autophagy signaling pathway. DOPW was structurally characterized. Its anti-fibrotic efficacy was evaluated in a mouse model of CCl₄-induced hepatic fibrosis and in TGF-β1-induced LX-2 cells. Mechanistic investigations integrated transcriptomic analysis (RNA‑seq) with pharmacological targeting of ERK1/2 signaling and autophagy, combined with 16S rRNA sequencing and fecal microbiota transplantation (FMT) to assess the role of the gut microbiota. The key microbial metabolite butyrate was quantified in both colonic and hepatic tissues. DOPW is a polysaccharide (256 kDa) composed of glucose and mannose in a 5:1 molar ratio. DOPW dose-dependently alleviated hepatic fibrosis, reducing liver injury, inflammation, and collagen deposition (all p < 0.001). Mechanistically, DOPW activated hepatic stellate cell autophagy by inhibiting ERK1/2 signaling, as confirmed by rescue experiments with ERK1/2 modulators (all p < 0.05). Notably, DOPW enriched short-chain fatty acid-producing gut microbiota (Parabacteroides, Bifidobacterium, and Prevotella), elevated fecal butyrate by 2.11-fold (p = 0.0443), and reinforced intestinal barrier integrity (all p < 0.05). These microbiota and metabolite changes were associated with suppression of hepatic ERK1/2 phosphorylation. Antibiotic depletion abolished these effects, while FMT with DOPW-modified microbiota reproduced the anti-fibrotic benefits (all p < 0.05). DOPW attenuates hepatic fibrosis by remodeling gut microbiota to enhance short-chain fatty acid production and intestinal barrier integrity, with butyrate and ERK1/2-dependent autophagy emerging as key mediators of this gut-liver crosstalk. These findings position DOPW as a promising microbiota-targeted anti-fibrotic candidate.

ID: 42492693
Title: Necroptosis and Cellular Stress Characterize Immune and Endothelial Dysfunction in Long COVID.
Abstract: Long COVID, or Post-Acute Sequelae of SARS-CoV-2 infection (PASC), affects a significant proportion of COVID-19 survivors and is associated with persistent fatigue, dysautonomia, and cardiovascular complications. The cellular mechanisms underlying these chronic symptoms remain incompletely understood. Investigate immune and endothelial cell dysfunction, with a focus on cell stress and death pathways, in individuals with Long COVID compared to matched infection-recovered controls. We conducted a cross-sectional study at the University of Miami Miller School of Medicine and the Miami VA Healthcare System enrolling adults who met WHO criteria for Long COVID and age- and sex-matched controls with no history of Long COVID symptoms were recruited. Clinical assessments included COVID-19 Yorkshire Rehabilitation Scale (C19-YRSm), Composite Autonomic Symptoms Score (COMPASS-31), heart rate variability (HRV), and vascular reactivity index (VRI). Peripheral blood was analyzed by spectral flow cytometry to characterize immune cell and circulating endothelial cell (CEC) populations and their expression of markers related to necroptosis (pMLKL), autophagy (LC3), hypoxia (HIF1-1α), and neutrophil extracellular traps (MPO, CitH3, NE). Long COVID patients (n=73) showed significantly higher Long COVID symptom scores compared to controls (n=41), along with impaired HRV and endothelial reactivity. Flow cytometry revealed increased expression of pMLKL, and LC3 in classical and non-classical monocytes, neutrophils, and eosinophils. CECs from Long COVID participants were substantially increased and demonstrated marked activation of necroptosis and autophagy pathways. These findings were accompanied by increased monocyte-platelet and CEC-platelet aggregates, consistent with a prothrombotic state. Elevated pMLKL expression in CECs strongly correlated with symptom severity and autonomic dysfunction. Our findings demonstrate that Long COVID is characterized by persistent inflammation and endothelial stress, involving necroptosis, and autophagy pathways. These mechanisms may contribute to chronic vascular and autonomic dysfunction in Long COVID patients. Targeting these stress and death signaling pathways may offer novel therapeutic strategies to mitigate the long-term consequences of SARS-CoV-2 infection.

ID: 42492799
Title: Sodium-glucose cotransporter 1 exacerbates colon cancer malignancy by suppressing ferroptosis via the Nrf2/HO-1/SLC7A11/GPX4 axis under high glucose conditions.
Abstract: Hyperglycemia is an independent risk factor for colon cancer progression, but its underlying mechanisms remain unclear. Ferroptosis is a form of programmed cell death, yet whether sodium-glucose cotransporter 1 (SGLT1) regulates ferroptosis to affect colon cancer under high glucose has not been reported. This study aims to clarify the mechanism by which SGLT1 regulates the malignant phenotype of colon cancer under high-glucose conditions and explore the therapeutic potential of targeting SGLT1 combined with ferroptosis inducers. HT29 and SW480 cells were treated with mmol/L high glucose. Cell proliferation and migration were detected by CCK-8, colony formation and wound-healing assays. Ribonucleic acid sequencing (RNA-seq) screened SGLT1-regulated downstream pathways. Ferroptosis was evaluated by malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS), ferrous ions (Fe2+) levels and mitochondrial ultrastructure. Western blot detected nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1)/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) pathway proteins. Interventions included ferrostatin-1 (Fer-1), tert-butylhydroquinone (TBHQ) and SLC7A11 overexpression. In vivo antitumor efficacy was assessed in diabetic nude mouse xenografts. High glucose significantly enhanced HT29 and SW480 cell viability, colony formation and migration, with upregulated SGLT1. SGLT1 knockdown reversed these phenotypes, while overexpression aggravated them. RNA-seq showed ferroptosis was the most enriched pathway after SGLT1 knockdown, with downregulated GPX4 and SLC7A11. Only Fer-1 reversed SGLT1 knockdown-induced cell viability decrease (78.5%, P<0.0001). SGLT1 knockdown increased MDA (3.53/3.40 vs. 2.33 nmol/mL, P<0.0001), ROS (6.91/7.12 vs. 3.57 a.u., P<0.01) and Fe2+ (44.50/44.74 vs. 8.54 a.u., P<0.0001), decreased GSH (35.93/37.04 vs. 46.96 μg/mL, P<0.0001), and induced mitochondrial atrophy; overexpression had opposite effects. SLC7A11 overexpression restored GPX4 (0.97 vs. 0.40, P=0.0187) and reversed ferroptosis and growth inhibition. SGLT1 knockdown suppressed Nrf2/HO-1, which was rescued by TBHQ, increasing HO-1 (1.03 vs. 0.62, P=0.0218), SLC7A11 (0.99 vs. 0.56, P=0.0303) and GPX4 (1.37 vs. 0.30, P=0.0065), while concurrently reversing ferroptosis. In vivo, SGLT1 knockdown reduced tumor weight from 264.6 to 36.76 mg (P<0.0001); mizagliflozin plus erastin achieved 90.69% tumor inhibition (Bliss score 0.087). High glucose promotes colon cancer cell proliferation and migration by upregulating SGLT1. SGLT1 is a key driver of high glucose-induced colon cancer malignant phenotypes. SGLT1 knockdown inhibits colon cancer mainly by activating ferroptosis, characterized by increased lipid peroxidation, GSH depletion, iron accumulation and mitochondrial atrophy. SGLT1 regulates ferroptosis via the SLC7A11/GPX4 axis. It inhibits ferroptosis by activating Nrf2/HO-1 to upregulate SLC7A11 and GPX4. Targeting SGLT1 enhances colon cancer cell sensitivity to ferroptosis inducers. Combined targeting of SGLT1 and ferroptosis is a novel therapeutic strategy for diabetic colon cancer patients.

ID: 42494062
Title: CX3CR1+ macrophages aggravate doxorubicin-induced cardiomyopathy by impairing cardiac mitophagy via the CSF1R-PARP1-IL1B axis.
Abstract: Doxorubicin is a widely used chemotherapeutic agent, but its clinical application is hindered by severe cardiotoxicity. Among immune cells, Cx3cr1+ macrophages have emerged as key regulators of cardiovascular disease, with their development and maturation tightly controlled by CSF1R (colony stimulating factor 1 receptor). Using multi-omics sequencing, we observed a marked expansion of Cx3cr1+ macrophages in doxorubicin-induced cardiomyopathy, yet their precise functional role in this pathological process has remained elusive. This study employed various genetically modified mouse models, including cell depletion models, lineage tracing models, and conditional gene knockout models targeting Cx3cr1+ macrophages, alongside transcriptomic sequencing, proteomic profiling, and multi-level in vivo and in vitro experiments to elucidate the role and mechanisms of Cx3cr1+ macrophages and their receptor CSF1R in doxorubicin-induced cardiac injury. We found that Cx3cr1+ macrophages are significantly enriched in hearts affected by doxorubicin-induced cardiomyopathy, and their depletion notably improves cardiac function. Further investigation revealed that in these macrophages, CSF1R competitively binds to the E3 ubiquitin ligase NEDD4, thereby inhibiting the ubiquitination and degradation of PARP1. This process promotes inflammasome activation and pyroptosis, driving massive IL1B secretion. IL1B directly suppresses cardiomyocyte mitophagy, disrupts energy metabolic homeostasis, and ultimately leads to cardiac dysfunction. Notably, the use of the CSF1R inhibitor PLX3397 or an IL1B-neutralizing antibody effectively halted these pathological processes and significantly improved cardiac function. In summary, this study unveils a novel mechanism through which Cx3cr1+ macrophages regulate cardiomyocyte function via the CSF1R-PARP1-IL1B-mitophagy signaling axis, providing a new theoretical foundation and intervention strategy for doxorubicin-induced cardiomyopathy targeted therapy.Abbreviations: BMDM: bone marrow-derived macrophages; CKMB: creatine kinase MB isoenzyme; CSF1R: colony stimulating factor 1 receptor; csf1r-cKO: csf1r conditional knockout; DIC: doxorubicin-induced cardiomyopathy; DOX: doxorubicin; HE: hematoxylin and eosin; HW:TL: heart weight:tibial length; LDH: lactate dehydrogenase; MAP1LC3/LC3: microtuble-associated protein 1 light chain 3; NPPA: natriuretic peptide type A; PI: propidium iodide; PYCARD/ASC: PYD and CARD domain containing; TNNT2/cTnT: troponin T2, cardiac; WGA: wheat germ agglutinin.

ID: 42494065
Title: IL17A disrupts autophagy-lysosomal function and lysosome reformation through the GSK3B-TFE3 signaling pathway in Huntington disease.
Abstract: Huntington disease (HD) is a progressive neurodegenerative disease caused by an expanded CAG repeat in the HTT (huntingtin) gene, leading to the accumulation of mutant HTT (mHTT). IL17A (interleukin 17A), a proinflammatory cytokine primarily secreted by Th17 and γδ T cells, has been implicated in immune-mediated neurodegeneration. However, the role of IL17A in the pathogenesis of HD remains poorly understood. Here, we identify IL17A as a critical pathogenic factor in HD that promotes neuroinflammation, mHTT aggregation, and autophagy-lysosomal dysfunction. IL17A disrupts autophagic flux by downregulating CTSB and CTSD, inducing SQSTM1/p62 and MAP1LC3B-II/LC3-II accumulation, and impairing lysosomal reformation. Mechanistically, IL17A suppresses lysosomal biogenesis by inhibiting the nuclear translocation of TFE3. This regulation occurs via a novel GSK3B/GSK-3β-TFE3 signaling pathway. Therapeutic neutralization of IL17A with a monoclonal antibody (IL17A mAb) ameliorates disease phenotypes in R6/2 HD mice, improving motor performance, extending survival, and reducing gliosis. IL17A mAb also attenuates mHTT aggregation and enhances neuroprotective signaling, as evidenced by increased expression of DLG4/PSD-95, phosphorylated CREB1, and BDNF. Moreover, IL17A mAb restores autophagy-lysosomal function by facilitating the clearance of protein aggregates and upregulating lysosomal enzymes and biogenesis markers, including CTSB, CTSD, PIP5K1A, and LAMP2. These findings establish IL17A as a key modulator of HD pathophysiology and highlight IL17A inhibition as a promising therapeutic strategy for targeting autophagy-lysosomal dysfunction in HD.

ID: 42496762
Title: Atranorin suppresses the LUCAT1/STAT3 axis to induce ferroptotic cell death in ovarian cancer.
Abstract: Ovarian cancer remains the most lethal gynecological malignancy and represents a major cause of cancer-related mortality among women worldwide. Despite advances in therapeutic strategies, treatment efficacy is frequently limited by systemic toxicity, chemoresistance, and disease recurrence, highlighting the urgent need for novel, mechanism-based targeted therapies with improved safety profiles. In the present study, we investigated the anti-cancer activity of atranorin (ATR), a naturally derived small-molecule compound, with a particular focus on its ability to induce ferroptosis by modulation of the LUCAT1/STAT3 signaling axis. Human ovarian cancer cell lines (OVCAR-3 and SKOV-3) and normal ovarian surface epithelial (OSE) cells were employed to evaluate cytotoxic selectivity and mechanistic effects. ATR selectively inhibited proliferation of ovarian cancer cells while exerting minimal cytotoxicity toward normal OSE cells. Mechanistic analyses demonstrated that ATR significantly suppressed LUCAT1 and STAT3 expression at both mRNA and protein levels, as confirmed by qRT-PCR and Western blotting. Concomitantly, ATR upregulated ferroptosis-related genes and proteins. Biochemical assessments revealed increased intracellular reactive oxygen species (ROS), elevated malondialdehyde (MDA) and iron accumulation, and depletion of glutathione (GSH), collectively indicating activation of ferroptotic cell death. Furthermore, ATR significantly impaired migratory and invasive capacities of ovarian cancer cells. Collectively, our findings identify ATR as a compound capable of inducing biochemical features consistent with ferroptosis in ovarian cancer through suppression of the LUCAT1/STAT3 axis. These results uncover a previously uncharacterized mechanistic pathway underlying ATR-mediated anti-tumor effect and support its potential development as a targeted therapeutic candidate for ovarian cancer management.

ID: 42496777
Title: A combination of artemisinin, moxidectin, and doxorubicin drugs can selectively and efficiently induce apoptosis in acute lymphoblastic and chronic myeloid leukemia cells in vitro and ex vivo.
Abstract: Acute lymphoblastic (ALL) and chronic myeloid (CML) leukemias are blood cancers that often resist traditional chemotherapy and other treatments. This is likely due to their ability to evade apoptosis. Therefore, inducing apoptosis in leukemia cells using innovative drug combinations may be the most effective therapeutic approach. Methods for multidrug combinations involving three or more drugs are scarce and much more complex to analyze. To address this issue, we propose an effective concentration 50 (EC50)-based, three-step method. The first step determines the lowest EC50 for each drug (e.g., artemisinin, chloroquine, primaquine, mefloquine, ivermectin, moxidectin, doxorubicin, and minocycline) by analyzing four cell endpoints (e.g., cell cycle, sub-G1, mitochondrial membrane potential (ΔΨm), autophagy (lysosomes), and cleaved caspase 3 (CC3)) on K562 cells. Step two involves establishing the deleterious effect of the EC50-based drug combination at concentrations of single drugs at 1-, ½-, and ¼-EC50, respectively, on K562 leukemia cells. Step three involves using the optimal combined drugs to evaluate the same cellular endpoints in other non-leukemic and leukemic cells. We found that the combination of AM (1 µM), MD (10 µM), and DR (1.5 µM), i.e., at ½ EC50, induced cell cycle arrest in the S (25% ± 13, N = 4) and G2/M (55% ± 18, N = 4) phases, a drastic loss of ΔΨm (81% ± 6, N = 4), high lysosome accumulation (82% ± 10, N = 4), and CC3 (83% ± 13, N = 4), as evidence of apoptosis in K562 and Jurkat cells and ex vivo ALL and CML cells. The combined drugs were innocuous to peripheral blood lymphocytes (PBLs) (S phase = 40%; G2/M = 26%; ΔΨm = 4%; lysosomes = 3%; CC3 = 4%; n = 3). Our approach to combining drugs has the potential to provide a new pharmacological treatment for leukemias.

ID: 42496814
Title: Lapatinib Induces Ferroptosis in Cardiomyocytes by Regulating ATF4/GPX4.
Abstract: The TKI-targeted agent lapatinib has been applied in clinical oncology for the management of multiple malignancies. Nonetheless, its therapeutic benefit is restricted by cardiotoxic effects that endanger patient survival, and the underlying molecular basis remains unclear. The GSE146096 dataset containing transcriptomic profiles of lapatinib-exposed human cardiomyocytes was analyzed to identify ferroptosis-related differentially expressed genes (DEGs). Protein expression of selected targets was subsequently confirmed by Western Blot. Reactive oxygen species (ROS) accumulation, Fe²⁺ levels, and mitochondrial membrane potential in AC16 cells exposed to lapatinib were examined using confocal microscopy. A microplate reader was employed to quantify alterations in malondialdehyde (MDA) and glutathione (GSH) levels in cardiomyocytes. Eight ferroptosis-associated genes were identified in lapatinib-treated cardiomyocytes, including the canonical regulator GPX4. siRNA interference and Western Blot analyses demonstrated marked induction of ATF4 expression and significant suppression of GPX4 expression following lapatinib exposure in AC16 cells. CCK-8 assays indicated dose-dependent cytotoxicity. Confocal microscopy and transmission electron microscopy (TEM) revealed altered mitochondrial morphology accompanied by a reduction in mitochondrial membrane potential. Intracellular MDA levels increased substantially, whereas GSH levels declined, indicating lipid peroxidation and subsequent ferroptosis. Treatment with the ferroptosis inhibitor Ferrostatin-1 (Fer-1) or silencing of ATF4 expression effectively attenuated lapatinib-induced cytotoxicity. Lapatinib enhances ATF4 expression in cardiomyocytes, suppresses GPX4, triggers lipid peroxidation, induces ferroptosis, and thereby contributes to cardiotoxicity.

ID: 42496855
Title: In Vivo Longitudinal Mapping of Brain Iron Accumulation After Pilocarpine-Induced Status Epilepticus.
Abstract: Iron accumulations have been identified in resected tissue from patients with refractory temporal lobe epilepsy. These deposits are linked to ferroptosis, a form of nonapoptotic cell death in which iron catalyzes the formation of reactive oxygen species, leading to lipid peroxidation. Experimentally, this process has recently been associated with seizures based on the increased levels of specific markers (4-hydroxynonenal and malondialdehyde) in the brain and plasma. Quantitative susceptibility mapping (QSM) offers an opportunity to detect the iron accumulations in vivo. In this study, we investigated how pilocarpine-induced status epilepticus contributes to the generation of iron deposits in diverse cerebral regions and whether QSM can detect these deposits longitudinally. We scanned 14 animals (n = 10 experimental and n = 4 control) at five different time points (pre-status epilepticus induction and 1, 7, 14, 21 days postinduction) using QSM. We identified iron deposits in the caudate putamen, hippocampus, thalamus, and primary somatosensory cortex of experimental animals, which is consistent with histological findings. The initial size of the hippocampal iron deposits significantly increased over the following weeks. None of these effects was observed in the control animals. The presence of cerebral iron depositions in epilepsy-related brain structures suggests that they could be involved in the onset, development, and progression of spontaneous recurrent seizures. Furthermore, noninvasive, longitudinal in vivo mapping of brain iron deposits could be a potential imaging marker in neurological disorders such as epilepsy. Future experiments will be required to determine the origin of the iron and avoid its progressive accumulation.