The different autophagy degradation pathways and neurodegeneration

Exploring the therapeutic potential of 4,4'-dimethoxychalcone: Inducing apoptosis in cancer cells via ER stress and autophagy disruption

In cancer therapeutics, natural flavonoid compounds are renowned for their diverse structures and broad biological activities, offering considerable opportunities for drug discovery. This study investigates the anticancer effects of the flavonoid 4,4'-dimethoxychalcone (DMC), focusing on its apoptotic mechanisms and therapeutic potential. Our findings reveal that DMC induces apoptosis by upregulating pro-apoptotic proteins (Bax, Bim, tBid) and downregulating anti-apoptotic proteins (Bcl-2, Mcl-1), with concurrent caspase-3 activation and PARP cleavage. This apoptotic effect is mitigated by Z-VAD-FMK, a pan-caspase inhibitor. DMC also induces mitochondrial membrane potential (MMP) loss and increases reactive oxygen species (ROS) production. Furthermore, DMC promotes endoplasmic reticulum (ER) stress, evidenced by the increased expression of p-PERK/PERK, p-IRE1/IRE1, GRP78, HSP70, ATF4, and CHOP proteins. ER stress inhibitors significantly reverse DMC-induced MMP loss, apoptosis, and upregulation of apoptosis-related proteins. Additionally, DMC activates the mitogen-activated protein kinase (MAPK) pathway, including Erk, JNK, and p38. DMC also promotes autophagosome accumulation, modulates autophagy marker proteins (LC3-II, ATG5, p62), and leads to lysosomal dysfunction-evidenced by downregulated LAMP-1 and Cathepsin D expression, lysosomal pH increase, yet unaffected LC3 and LAMP-1 co-localization. Modulating autophagy with inhibitors (3-methyladenine, 3-MA; chloroquine, CQ) or an inducer (rapamycin, Rapa) respectively enhances or reduces DMC-induced apoptosis. Treatment with 3-MA also led to a significant increase in the expression of ER stress markers CHOP and ATF4. Collectively, DMC-induced cell death is primarily due to ER stress activation and autophagic flux impairment via lysosomal dysfunction. These results suggest DMC's potential as an anticancer agent, warranting further clinical investigation.

Autophagy-targeting modulation to promote peripheral nerve regeneration

Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms. Past studies have focused on factors that stimulate axonal outgrowth and myelin regeneration. However, recent studies have highlighted the pivotal role of autophagy in peripheral nerve regeneration, particularly in the context of traumatic injuries. Consequently, autophagy-targeting modulation has emerged as a promising therapeutic approach to enhancing peripheral nerve regeneration. Our current understanding suggests that activating autophagy facilitates the rapid clearance of damaged axons and myelin sheaths, thereby enhancing neuronal survival and mitigating injury-induced oxidative stress and inflammation. These actions collectively contribute to creating a favorable microenvironment for structural and functional nerve regeneration. A range of autophagy-inducing drugs and interventions have demonstrated beneficial effects in alleviating peripheral neuropathy and promoting nerve regeneration in preclinical models of traumatic peripheral nerve injuries. This review delves into the regulation of autophagy in cell types involved in peripheral nerve regeneration, summarizing the potential drugs and interventions that can be harnessed to promote this process. We hope that our review will offer novel insights and perspectives on the exploitation of autophagy pathways in the treatment of peripheral nerve injuries and neuropathies.

Inhibition of autophagy in the amygdala ameliorates anxiety-like behaviors induced by morphine-protracted withdrawal in male mice

OBJECTIVE

Morphine withdrawal triggers a range of negative affective states, wherein anxiety is typically common, significantly contributing to the morphine relapse. To date, the exact mechanism underlying morphine withdrawal-induced anxiety has remained unclear. Previous studies have proposed that autophagy is involved in the pathogenesis of morphine addiction and anxiety; however, the possible relationship between autophagy and morphine withdrawal-induced anxiety has not been explored before. In this study, we aimed to reveal the potential role of autophagy in anxiety-like behaviors elicited by protracted morphine withdrawal, and which brain region is involved.

METHODS

We established the model mice of anxiety by chronic intermittent escalating-dose morphine administration for 7 days and then withdrawing for 4 days. Anxious behaviors were detected using the Open field test and the Elevated plus maze test. Western blot was performed to measure the change of autophagy-associated proteins (ATG5, Beclin-1, LC3) in different brain regions.

RESULTS

Our results showed that intraperitoneal injection of an autophagy inhibitor 3-Methyladenine attenuated protracted morphine withdrawal-induced anxiety-like behaviors in male mice. Moreover, protracted morphine withdrawal predominantly promoted autophagy in the amygdala, rather than other related brain regions, suggesting the crucial involvement of amygdala in autophagy-mediated anxiety after morphine withdrawal. We further validated that 3-Methyladenine can effectively reduce autophagy-associated protein levels in the relevant brain region.

CONCLUSION

These findings indicated that protracted morphine withdrawal-elicited autophagy in the amygdala contributes to the anxiety-like behaviors and may have implications for the future treatment of this disorder.

MicroRNA sequencing analysis in pediatric patients with influenza-associated acute necrotizing encephalopathy: Potential biomarkers for early diagnosis and therapy

Acute necrotizing encephalopathy (ANE) secondary to influenza infection is characterized by fulminant neurological deterioration and a high mortality rate. The underlying mechanisms remain unclear, and specific treatments are currently lacking. Therefore, understanding the pathogenesis and identifying diagnostic and therapeutic targets for influenza-induced ANE are crucial. Peripheral blood samples were collected from two groups: influenza-infected patients without ANE (mild) and influenza infection with ANE patients (severe). Differentially expressed genes (DEG) were identified through microRNA sequencing analysis, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The expression levels of the four specific miRNAs were validated using qRT-PCR. In the severe group, 24 genes were up-regulated, and 67 genes were down-regulated compared to the mild group. The expression levels of hsa-miR-1290, hsa-miR-4657, has-miR-1231, and hsa-miR-342-3p were validated by qRT-PCR, and the levels of has-miR-4657 and hsamiR- 342-3p showed significant differences between severe and mild groups. GO analysis demonstrated that the DEGs were predominantly involved in the positive regulation of cellular processes, intracellular anatomical structure, and protein binding. KEGG pathway analysis revealed that DEGs were mainly enriched in calcium signaling pathway and axon guidance. The down-regulated hsa-miR-4657 and hsa-miR-342-3p might be associated with the development of ANE in pediatric patients with influenza by regulation of calcium pathways and axon guidance.

Perfluorooctanoic acid (PFOA) activates astrogliosis-associated neuroinflammation through ER stress-autophagy axis

Perfluorooctanoic acid (PFOA), a perfluoroalkyl acid, induces neuroinflammation. However, present understanding regarding its fundamental role in neuroinflammation remains limited. Therefore, in this study, we aimed to clarify the potential association between PFOA and astrocyte activation via the modulation of the endoplasmic reticulum (ER) stress-autophagy axis. The results obtained revealed that PFOA activated astroglia in A-172 astrocytoma cells and primary astrocytes by upregulating the expression levels of autophagy-related proteins (ATG5, BECN1, SQSTM1, and MAP1LC3B-II). It also activated autophagy in A-172 astrocytoma cells and primary astrocytes via the upstream activation of ER stress-related proteins, such as ATF4, GRP78, and CHOP. Further, the pharmacological inhibition of ER stress as well as autophagy prevented PFOA-induced activation of astrogliosis in PFOA-treated A-172 cells and primary astrocytes. We also observed that PFOA-mediated activation of GFAP upregulated the transcription of pro-inflammatory cytokines, such as IL-1β, TNF-α, and IL-6. These findings confirmed the existence of a relationship between ER stress-induced autophagy and astrogliosis in PFOA-treated astrocytes, suggesting that targeting the ER stress-autophagy axis may be a potential therapeutic strategy for reducing PFOA-induced neuroinflammation.

Targeting LKB1-AMPK-SIRT1-induced autophagy and mitophagy pathways improves cerebrovascular homeostasis in APP/PS1 mice

BACKGROUND

Alzheimer's disease (AD) is the most common and severe degenerative disorder of the central nervous system in the elderly, profoundly impacting patients' quality of life. However, effective therapeutic agents for AD are still lacking. Bazi Bushen capsule (BZBS) is a traditional Chinese herbal compound with potential neuroprotective effects, yet its underlying mechanisms remain poorly understood.

METHODS

In this study, we utilized APP/PS1 transgenic mice to assess the therapeutic efficacy of BZBS. Initially, we evaluated the spatial learning and memory of the mice using the Barnes maze. The brain microcirculation was assessed through a small-animal ultrasound system, two-photon in vivo imaging, and micro-computed tomography angiography. Molecular, biochemical, and pathological analyses were conducted on brain tissues. Through network pharmacology, we identified potential intervention pathways and targets for BZBS in the treatment of AD, which we subsequently validated both in vivo and in vitro. Additionally, we employed molecular virtual docking screening and biolayer interferometry to elucidate the direct interactions of ginsenoside Rg5 and ginsenoside Ro in BZBS with AMPK and LKB1 proteins.

RESULTS

The BZBS intervention significantly enhanced spatial learning and memory in APP/PS1 mice while decreasing Aβ deposition. Furthermore, BZBS protected cerebrovascular homeostasis and mitigated neuroinflammation, as evidenced by decreased blood-brain barrier permeability, increased expression of tight-junction proteins, and restored cerebral blood flow. Mechanistically, ginsenosides Rg5 and Ro in BZBS directly bind to AMPK and LKB1 proteins, activating the LKB1-AMPK-SIRT1 signaling pathway, promoting autophagy and mitochondrial autophagy, and alleviating oxidative stress damage in endothelial cells.

CONCLUSIONS

BZBS enhances autophagy-related activity, decreases Aβ deposition, and improves endothelial cell homeostasis through the activation of the LKB1-AMPK-SIRT1 signaling pathway, ultimately leading to improved cognitive function in mice with AD. This study highlights the importance of enhancing autophagic activity and maintaining cerebrovascular homeostasis in mitigating cognitive decline in AD, providing evidence and new insights into the application of compound medicines for treating age-related neurological disorders.

Autolysosomal Dysfunction in Obesity-induced Metabolic Inflammation and Related Disorders

PURPOSE OF REVIEW

Obesity is a global health crisis affecting individuals across all age groups, significantly increasing the risk of metabolic disorders such as type 2 diabetes (T2D), metabolic dysfunction-associated fatty liver disease (MAFLD), and cardiovascular diseases. The World Health Organization reported in 2022 that 2.5 billion adults were overweight, with 890 million classified as obese, emphasizing the urgent need for effective interventions. A critical aspect of obesity's pathophysiology is meta-inflammation-a chronic, systemic low-grade inflammatory state driven by excess adipose tissue, which disrupts metabolic homeostasis. This review examines the role of autolysosomal dysfunction in obesity-related metabolic disorders, exploring its impact across multiple metabolic organs and evaluating potential therapeutic strategies that target autophagy and lysosomal function.

RECENT FINDINGS

Emerging research highlights the importance of autophagy in maintaining cellular homeostasis and metabolic balance. Obesity-induced lysosomal dysfunction impairs the autophagic degradation process, contributing to the accumulation of damaged organelles and toxic aggregates, exacerbating insulin resistance, lipotoxicity, and chronic inflammation. Studies have identified autophagic defects in key metabolic tissues, including adipose tissue, skeletal muscle, liver, pancreas, kidney, heart, and brain, linking autophagy dysregulation to the progression of metabolic diseases. Preclinical investigations suggest that pharmacological and nutritional interventions-such as AMPK activation, caloric restriction mimetics, and lysosomal-targeting compounds-can restore autophagic function and improve metabolic outcomes in obesity models. Autolysosomal dysfunction is a pivotal contributor to obesity-associated metabolic disorders , influencing systemic inflammation and metabolic dysfunction. Restoring autophagy and lysosomal function holds promise as a therapeutic strategy to mitigate obesity-driven pathologies. Future research should focus on translating these findings into clinical applications, optimizing targeted interventions to improve metabolic health and reduce obesity-associated complications.

6-shogaol alleviates excessive neuronal autophagy and calcium overload following cerebral ischemia-reperfusion injury by inhibiting the expression of DAPK1

Cerebral ischemia-reperfusion injury (CIRI) is the primary pathological mechanism of ischemic stroke, leading to neuronal damage and triggering a series of pathological changes. This study investigates the neuroprotective effects and underlying mechanisms of 6-shogaol (6-SH) in CIRI. By establishing an in vitro OGD/R model and a rat cerebral ischemia-reperfusion model, we found that 6-SH significantly improved neuronal viability, alleviated pathological damage, and reduced autophagosome formation. Additionally, 6-SH treatment markedly inhibited the expression of DAPK1, decreased intracellular calcium ion concentration, and mitigated excessive autophagy. Mechanistic studies indicated that 6-SH reduces neuronal injury induced by CIRI by modulating DAPK1 phosphorylation and inhibiting its activity. This discovery provides a theoretical basis for considering 6-SH as a potential neuroprotective agent and offers new insights for clinical treatment of ischemic stroke.

A Ginsenoside Composition Ameliorated Aβ and Tau Aggregation via Autophagy Lysosome Pathway

Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by the abnormal deposition of amyloid-beta (Aβ) peptides and neurofibrillary tangles (NFTs). Ginsenosides, the primary active constituents in ginseng, exhibit potential in combating AD. In our previous work, the ginsenoside SumI was demonstrated to have superior anti-AD activity compared to other ginsenosides when used alone. This study revealed that SumI effectively decreased the lysosomal pH, promoted autophagosome formation, increased autophagic flux, and facilitated the transport of misfolded proteins to lysosomes for degradation in Caenorhabditis elegans. SumI activated the HLH-30 transcription factor by triggering a lipid-catabolic response akin to starvation. bec-1 RNAi significantly abrogated the anti-AD effect of SumI. Our findings indicate that SumI mitigated protein aggregation by activating the autophagy-lysosome pathway in C. elegans and provide scientific evidence that ginsenoside composition could be a potential therapeutic agent for treating or preventing AD.

Exploring genetic and epigenetic markers for predicting or monitoring response to cognitive-behavioral therapy in obsessive-compulsive disorder: A systematic review

Growing evidence has identified potential biomarkers of cognitive-behavioural therapy (CBT) efficacy in obsessive-compulsive disorder (OCD). Genetic and epigenetic mechanisms (e.g., polymorphisms, DNA methylation) contribute to OCD pathogenesis and CBT response variability, establishing them as a key research focus. To evaluate their associations with CBT outcomes in OCD, we conducted a systematic review of PubMed, Web of Science, CNKI, and Cochrane Library (from inception to January 2025), identifying eight studies that met rigorous inclusion criteria. The identified predictors included: (1) Genetic polymorphisms (BDNF); (2) Epigenetic modifications (DNA methylation of MAOA, SLC6A4, OXTR, PIWIL1, MIR886, PLEKHA1, KCNQ1, TRPM8, HEBP1, HTR7P1, MAPK8IP3, ENAH, RABGGTB (SNORD45C), MYEF2, GALK2, CEP192, and UIMC1). These markers may influence neural plasticity, neurotransmitter regulation, and related processes, providing molecular substrates for the observed treatment effects. Converging evidence suggests that distinct neurocognitive mechanisms may mediate CBT efficacy in OCD, particularly fear extinction learning and goal-directed behaviors (GDBs), which we analyze mechanistically. Future studies should integrate polygenic risk scores (PRS) with functional neuroimaging to dissect individual variability in CBT response, mainly through cortico-striato-thalamo-cortical (CSTC) circuit profiling. To our knowledge, this is the first systematic review synthesizing genetic and epigenetic predictors of CBT response in OCD; these findings provide compelling evidence for biomarkers for CBT personalization in OCD, advancing a novel precision psychiatry framework.

Stress dynamically modulates neuronal autophagy to gate depression onset

Chronic stress remodels brain homeostasis, in which persistent change leads to depressive disorders1. As a key modulator of brain homeostasis2, it remains elusive whether and how brain autophagy is engaged in stress dynamics. Here we discover that acute stress activates, whereas chronic stress suppresses, autophagy mainly in the lateral habenula (LHb). Systemic administration of distinct antidepressant drugs similarly restores autophagy function in the LHb, suggesting LHb autophagy as a common antidepressant target. Genetic ablation of LHb neuronal autophagy promotes stress susceptibility, whereas enhancing LHb autophagy exerts rapid antidepressant-like effects. LHb autophagy controls neuronal excitability, synaptic transmission and plasticity by means of on-demand degradation of glutamate receptors. Collectively, this study shows a causal role of LHb autophagy in maintaining emotional homeostasis against stress. Disrupted LHb autophagy is implicated in the maladaptation to chronic stress, and its reversal by autophagy enhancers provides a new antidepressant strategy.

Radix Hedysari Polysaccharides modulate the gut-brain axis and improve cognitive impairment in SAMP8 mice

OBJECTIVE

Radix Hedysari Polysaccharides (RHP) are the principal bioactive constituents of the traditional Chinese medicinal herb Radix Hedysari. This study aims to evaluate the neuroprotective effects of RHP in both cellular and animal models of Alzheimer's disease (AD) and to elucidate the underlying molecular mechanisms.

METHODS

HT22 cells subjected to Aβ25-35-induced cytotoxicity were pretreated with RHP, followed by assessments of reactive oxygen species (ROS) generation, mitochondrial superoxide (mSOX) levels, and mitochondrial membrane potential (ΔΨm). Senescence-accelerated mouse-prone 8 (SAMP8) mice were orally administered RHP for 12 weeks. Behavioral assays were conducted to assess cognitive function, while metabolomic and proteomic analyses were performed to examine serum metabolic alterations and hippocampal protein expression profiles. Additionally, neuronal autophagy and gut barrier integrity were evaluated using immunohistochemistry, transmission electron microscopy, and biomarker quantification.

RESULTS

RHP treatment significantly attenuated Aβ25-35-induced oxidative stress in HT22 cells by reducing ROS and mSOX production while preserving ΔΨm. In SAMP8 mice, RHP improved cognitive performance, preserved hippocampal mitochondrial ultrastructure, and enhanced neuronal autophagic activity. Moreover, RHP modulated serum metabolic pathways and alleviated gut barrier dysfunction, suggesting a role in gut-brain axis regulation.

CONCLUSION

RHP ameliorates cognitive impairment in SAMP8 mice, potentially through its modulation of systemic metabolism, mitigation of neuronal mitochondrial damage, and restoration of gut barrier integrity. These findings highlight the therapeutic potential of RHP in AD intervention and warrant further investigation into its mechanistic underpinnings.

HBCOC attenuates cerebral ischemia-reperfusion injury in mice by inhibiting the inflammatory response and autophagy via TREM-1/ERK/NF-κB

OBJECTIVE

Hemoglobin-based carbon monoxide carrier (HBCOC) can dissociate carbon monoxide and ameliorate organ damage by inhibiting inflammation and oxidative stress. In this study, we evaluated its effect on cerebral ischemia-reperfusion injury in mice and explored its potential mechanism.

METHODS

A middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model was established using the wire embolization method, and HBCOC or equivalent normal saline was administered via the tail vein during reperfusion. HE staining and TEM were used to observe the injury in the tissue. The levels of IL-1β, IL-6, TNF-α were detected by ELISA and RT-qPCR, meantime, western blotting were used to detect expressions of TREM-1, ERK, NF-κB,LC3 and P62.

RESULTS

We found that the HBCOC treatment alleviated nerve injury and reduced the cerebral infarction area caused by ischemia-reperfusion, simultaneously lowered the expression of IL-1β, IL-6, and TNF-α in plasma and brain tissues. HBCOC suppressed the levels of LC3II, lysosomes, and autophagy in the brain, suggesting potent inhibition of autophagy. Mechanistic analysis indicated that the expression of TREM-1/ERK/NF-κB pathway-related proteins and mRNA was higher in the saline group than that in the HBCOC group. HBCOC combined with the targeting TREM-1 receptor inhibitors LP17 inhibited the expression of the TREM-1 protein, further reducing the release of inflammatory factors and autophagy, restoring nerve function and infarct area after reperfusion, and exerting an overall protective effect against cerebral reperfusion injury. In summary, our results indicated that HBCOC alleviated cerebral ischemia-reperfusion injury in mice and inhibited inflammation and autophagy via TREM-1.

Drosophila aux orchestrates the phosphorylation-dependent assembly of the lysosomal V-ATPase in glia and contributes to SNCA/α-synuclein degradation

Glia contribute to the neuropathology of Parkinson disease (PD), but how they react opposingly to be beneficial or detrimental under pathological conditions, like promoting or eliminating SNCA/α-syn (synuclein alpha) inclusions, remains elusive. Here we present evidence that aux (auxilin), the Drosophila homolog of the PD risk factor GAK (cyclin G associated kinase), regulates the lysosomal degradation of SNCA/α-syn in glia. Lack of glial GAK/aux increases the lysosome number and size, regulates lysosomal acidification and hydrolase activity, and ultimately blocks the degradation of substrates including SNCA/α-syn. Whereas SNCA/α-syn accumulates prominently in lysosomes devoid of glial aux, levels of injected SNCA/α-syn preformed fibrils are further enhanced in the absence of microglial GAK. Mechanistically, aux mediates phosphorylation at the serine 543 of Vha44, the V1 C subunit of the vacuolar-type H+-translocating ATPase (V-ATPase), and regulates its assembly to control proper acidification of the lysosomal milieu. Expression of Vha44, but not the Vha44 variant lacking S543 phosphorylation, restores lysosome acidity, locomotor deficits, and DA neurodegeneration upon glial aux depletion, linking this pathway to PD. Our findings identify a phosphorylation-dependent switch controlling V-ATPase assembly for lysosomal SNCA/α-syn degradation in glia. Targeting the clearance of glial SNCA/α-syn inclusions via this lysosomal pathway could potentially be a therapeutic approach to ameliorate the disease progression in PD.Abbreviation: aux: auxilin; GAK: cyclin G associated kinase; LTG: LysoTracker Green; LTR: LysoTracker Red; MR: Magic Red; PD: Parkinson disease; SNCA/a-syn: synuclein alpha; V-ATPase: vacuolar-type H+-translocating ATPase.

The ER protein CANX (calnexin)-mediated autophagy protects against alzheimer disease

Although the relationship between macroautophagy/autophagy and Alzheimer disease (AD) is widely studied, the underlying mechanisms are poorly understood, especially the regulatory role of the initiation signaling of autophagy on AD. Here, we find that the ER transmembrane protein CANX (calnexin) is a novel interaction partner of the autophagy-inducing kinase ULK1 and is required for ULK1 recruitment to the ER under basal or starved conditions. Loss of CANX results in the inactivity of ULK1 kinase and inhibits autophagy flux. In the brains of people with AD and APP-PSEN1 mice, the interaction of CANX and ULK1 declines. In mice, the lack of CANX in hippocampal neurons causes the accumulation of autophagy receptors and neuron damage, which affects the cognitive function of C57BL/6 mice. Conversely, overexpression of CANX in hippocampal neurons enhances autophagy flux and partially contributes to improving cognitive function of APP-PSEN1 mice, but not the CANX variant lacking the interaction domain with ULK1. These findings reveal a novel role of CANX in autophagy activity and cognitive function by cooperating with ULK1.Abbreviation: AD: Alzheimer disease; APEX: ascorbate peroxidase; APP: amyloid beta precursor protein; APP-PSEN1 mice: amyloid beta precursor protein-presenilin 1 transgenic mice; ATG: autophagy related; Aβ: amyloid-β; BiFC: bimolecular fluorescence complementation; CANX: calnexin; EBSS: Earle's balanced salt solution; EM: electron microscopy; IP: immunopurification; KO: knockout; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MWM: Morris water maze; PLA: proximity ligation assay; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; SQSTM1/p62, sequestosome 1.

Quitting Your Day Job in Response to Stress: Cell Survival and Cell Death Require Secondary Cytoplasmic Roles of Cyclin C and Med13

Following unfavorable environmental cues, cells reprogram pathways that govern transcription, translation, and protein degradation systems. This reprogramming is essential to restore homeostasis or commit to cell death. This review focuses on the secondary roles of two nuclear transcriptional regulators, cyclin C and Med13, which play key roles in this decision process. Both proteins are members of the Mediator kinase module (MKM) of the Mediator complex, which, under normal physiological conditions, positively and negatively regulates a subset of stress response genes. However, cyclin C and Med13 translocate to the cytoplasm following cell death or cell survival cues, interacting with a host of cell death and cell survival proteins, respectively. In the cytoplasm, cyclin C is required for stress-induced mitochondrial hyperfission and promotes regulated cell death pathways. Cytoplasmic Med13 stimulates the stress-induced assembly of processing bodies (P-bodies) and is required for the autophagic degradation of a subset of P-body assembly factors by cargo hitchhiking autophagy. This review focuses on these secondary, a.k.a. "night jobs" of cyclin C and Med13, outlining the importance of these secondary functions in maintaining cellular homeostasis following stress.

Chaperone-mediated autophagy sustains pericyte stemness necessary for brain tissue homeostasis

INTRODUCTION

Pericytes (PCs) are mural cells exhibiting some mesenchymal stem cell (MSC) properties and contribute to tissue regeneration after injury. We have previously shown that glioblastoma cancer cells induce in PCs, a pathogenic upregulation of chaperone-mediated autophagy (CMA) which modulates immune functions and MSC-like properties to support tumor growth.

OBJECTIVES

The aim of the study was to interrogate the role of CMA-regulated MSC properties in PCs in the context of tissue repair during inflammation triggered by a demyelinating injury.

METHODS

Studies of RNA-seq were done PCs with (WT) and without (LAMP-2A KO) CMA. Cell characterization related to stemness, lineage and morphology was done in WT and KO PCs. Secretome analysis and cell differentiation assay using the supernatants from CMA-efficient and deficient PCs cultures was done in mesenchymal cells. Inflammatory response of brain cells was assessed with WT and KO PCs secretome. To corroborate in vitro results, CMA modulation in response to inflammation in PCs and tissue repair markers were measured in the lesion areas of a demyelination mouse model and correlated with the tissue reparation after intravenous PC administration. An inflammatory mediator was used to study effects on PC-CMA activity.

RESULTS

We found that inflammatory mediators such as IFNγ downregulate CMA in PCs, suppressing PC stemness and promoting a pro-inflammatory secretome. Restoration of PC CMA activity during inflammation maintains PC MSC properties and induces an MSC-like proteome which decreases inflammation and promotes tissue repair. We identified secreted proteins involved in regenerative and protective processes, and therefore, necessary to restore brain tissue homeostasis after inflammation induced by a demyelinating injury.

CONCLUSION

we show that manipulation of CMA activity in host PCs could be a useful therapeutical approach in the context of brain inflammation, which might be extended to other diseases where the pericyte has a key role in response to inflammation.

Conserved components of the macroautophagy machinery in Caenorhabditis elegans

Macroautophagy involves the sequestration of cytoplasmic contents in a double-membrane autophagosome and its subsequent delivery to lysosomes for degradation and recycling. In Caenorhabditis elegans, autophagy participates in diverse processes such as stress resistance, cell fate specification, tissue remodeling, aging, and adaptive immunity. Genetic screens in C. elegans have identified a set of metazoan-specific autophagy genes that form the basis for our molecular understanding of steps unique to the autophagy pathway in multicellular organisms. Suppressor screens have uncovered multiple mechanisms that modulate autophagy activity under physiological conditions. C. elegans also provides a model to investigate how autophagy activity is coordinately controlled at an organismal level. In this chapter, we will discuss the molecular machinery, regulation, and physiological functions of autophagy, and also methods utilized for monitoring autophagy during C. elegans development.

Mogroside III improves bovine oocyte in vitro maturation by regulating autophagy in cumulus cells

In vitro maturation (IVM) of oocytes is pivotal for successful embryo production. Cumulus cells (CCs) contribute to oocyte maturation through the secretion of hormones and nutrients, with proper autophagic activity being crucial for this process. However, the role of autophagy in CCs remains underexplored. Siraitia grosvenorii extract Mogroside III (MIII), known for its antioxidant properties, has yet to be extensively studied for its impact on bovine oocyte IVM and its potential regulatory effects on autophagy. This study assessed the influence of MIII on autophagic activity in CCs and its subsequent effects on oocyte developmental potential. The results demonstrated that MIII enhanced bovine oocyte IVM, promoted CC expansion, and supported embryonic development. Transcriptomic analysis indicated that MIII upregulated the expression of autophagy-related genes. In vitro experiments on CCs revealed that MIII increased LC3B protein levels, reduced SQSTM1 accumulation, and upregulated the gene expression of LC3, Beclin1, and ATG5. In co-culture systems, autophagy inhibition in CCs impaired oocyte IVM and embryonic development, but MIII alleviated these effects, restoring oocyte developmental capacity compromised by 3-MA-induced autophagy inhibition. Mechanistically, MIII facilitated the degradation of WT1 by upregulating LC3B, influencing CC differentiation, enhancing FSHR synthesis, and increasing estrogen and progesterone secretion. In conclusion, MIII enhances oocyte developmental potential by modulating autophagy in CCs.

The NR3C2-SIRT1 signaling axis promotes autophagy and inhibits epithelial mesenchymal transition in colorectal cancer

Colorectal cancer (CRC) is one of the most aggressive and lethal cancers with a complex pathogenesis, there is an urgent need to find new drug therapeutic targets. This study highlights the important role of the NR3C2-SIRT1 signaling axis in the metastasis mechanism of CRC. Our findings revealed that the expression of NR3C2 in CRC tissues was lower than that in adjacent non-cancerous tissues, and was negatively correlated with N stage by bioanalysis, IHC, western blot and qRT-PCR. NR3C2 overexpression / knockdown can significantly inhibit / promote the migration and invasion of CRC cells, at the same time inhibit / promote EMT. Mechanically, the regulatory molecule SIRT1 was identified by RNA-seq, bioinformatics analysis, western blot and ChIP. SIRT1 was also involved in the metastasis process of CRC, and NR3C2 was found to regulate the expression of LC3B and SQSTM1/p62 in a SIRT1-dependent manner. Therefore, NR3C2 forms a signaling axis with SIRT1, which can directly promote autophagy and inhibit EMT process in vivo and in vitro. Collectively, our findings suggest that NR3C2 - SIRT1 signal axis promote autophagy and inhibit EMT, ultimately inhibits lung metastasis of CRC.

Autophagy, ER-phagy and ER Dynamics During Cell Differentiation

The endoplasmic reticulum (ER) is a multifunctional organelle essential for protein and lipid synthesis, ion transport and inter-organelle communication. It comprises a highly dynamic network of membranes that continuously reshape to support a wide range of cellular processes. During cellular differentiation, extensive remodelling of both ER architecture and its proteome is required to accommodate alterations in cell morphology and function. Autophagy, and ER-phagy in particular, plays a pivotal role in reshaping the ER, enabling cells to meet their evolving needs and adapt to developmental cues. Despite the ER's critical role in cellular differentiation, the mechanisms responsible for regulating its dynamics are not fully understood. Emerging evidence suggests that transcriptional and post-translational regulation play a role in fine-tuning ER-phagy and the unfolded protein response (UPR). This review explores the molecular basis of autophagy and ER-phagy, highlighting their role in ER remodelling during cellular differentiation. A deeper understanding of these processes could open new avenues for targeted therapeutic approaches in conditions where ER remodelling is impaired.

Pitolisant alleviates brain network dysfunction and cognitive deficits in a mouse model of Alzheimer's disease

Histamine H3 receptor (H3R) antagonists regulate histamine release that modulates neuronal activity and cognitive function. Although H3R is elevated in Alzheimer's disease (AD) patients, whether H3R antagonists can rescue AD-associated neural impairments and cognitive deficits remains unknown. Pitolisant is a clinically approved H3R antagonist/inverse agonist that treats narcolepsy. Here, we find that pitolisant reverses AD-like pathophysiology and cognitive impairments in an AD mouse model. Behavioral assays and in vivo wide-field Ca2+ imaging revealed that recognition memory, learning flexibility, and slow-wave impairment were all improved following the 15-day pitolisant treatment. Improved recognition memory was tightly correlated with slow-wave coherence, suggesting slow waves serve as a biomarker for treatment response and for AD drug screening. Furthermore, pitolisant reduced amyloid-β deposition and dystrophic neurites surrounding plaques, and enhanced neuronal lysosomal activity, inhibiting which blocked cognitive and slow-wave restoration. Our findings identify pitolisant as a potential therapeutic agent for AD treatments.

Neuronal autophagy in the control of synapse function

Neurons are long-lived postmitotic cells that capitalize on autophagy to remove toxic or defective proteins and organelles to maintain neurotransmission and the integrity of their functional proteome. Mutations in autophagy genes cause congenital diseases, sharing prominent brain dysfunctions including epilepsy, intellectual disability, and neurodegeneration. Ablation of core autophagy genes in neurons or glia disrupts normal behavior, leading to motor deficits, memory impairment, altered sociability, and epilepsy, which are associated with defects in synapse maturation, plasticity, and neurotransmitter release. In spite of the importance of autophagy for brain physiology, the substrates of neuronal autophagy and the mechanisms by which defects in autophagy affect synaptic function in health and disease remain controversial. Here, we summarize the current state of knowledge on neuronal autophagy, address the existing controversies and inconsistencies in the field, and provide a roadmap for future research on the role of autophagy in the control of synaptic function.

Targeting chaperone-mediated autophagy in neurodegenerative diseases: mechanisms and therapeutic potential

The pathological hallmarks of various neurodegenerative diseases including Parkinson's disease and Alzheimer's disease prominently feature the accumulation of misfolded proteins and neuroinflammation. Chaperone-mediated autophagy (CMA) has emerged as a distinct autophagic process that coordinates the lysosomal degradation of specific proteins bearing the pentapeptide motif Lys-Phe-Glu-Arg-Gln (KFERQ), a recognition target for the cytosolic chaperone HSC70. Beyond its role in protein quality control, recent research underscores the intimate interplay between CMA and immune regulation in neurodegeneration. In this review, we illuminate the molecular mechanisms and regulatory pathways governing CMA. We further discuss the potential roles of CMA in maintaining neuronal proteostasis and modulating neuroinflammation mediated by glial cells. Finally, we summarize the recent advancements in CMA modulators, emphasizing the significance of activating CMA for the therapeutic intervention in neurodegenerative diseases.

Mitochondrial quality control disorder in neurodegenerative disorders: Potential and advantages of traditional Chinese medicines

Neurodegenerative disorders (NDDs) are prevalent chronic conditions characterized by progressive synaptic loss and pathological protein alterations. Increasing evidence suggested that mitochondrial quality control (MQC) serves as the key cellular process responsible for clearing misfolded proteins and impaired mitochondria. Herein, we provided a comprehensive analysis of the mechanisms through which MQC mediates the onset and progression of NDDs, emphasizing mitochondrial dynamic stability, the clearance of damaged mitochondria, and the generation of new mitochondria. In addition, traditional Chinese medicines (TCMs) and their active monomers targeting MQC in NDD treatment have been demonstrated. Consequently, we compiled the TCMs that show great potential in the treatment of NDDs by targeting MQC, aiming to offer novel insights and a scientific foundation for the use of MQC stabilizers in NDD prevention and treatment.

Hypomethylation induced overexpression of PLOD3 facilitates colorectal cancer progression through TM9SF4-mediated autophagy

Colorectal cancer (CRC) ranks among the primary causes of human mortality globally. Numerous studies have highlighted the significant role of PLOD3 in the progression of various cancers. However, the exact function and underlying mechanisms of PLOD3 in CRC remains incompletely understood. To investigate the expression of PLOD3, qRT‒PCR, immunohistochemistry and western blotting were utilized to analyze the expression of PLOD3 in CRC tissues and adjacent normal tissues. Functional assays were conducted to assess the roles of PLOD3 both in vitro and in vivo. To elucidate the potential mechanism of PLOD3 in CRC, a range of techniques, including coimmunoprecipitation, immunofluorescence, CHX pulse-chase, and ubiquitination assays were used. As the results indicated, hypomethylation of the PLOD3 promoter leads to its over- expression in CRC, and elevated PLOD3 levels are associated with a poor prognosis. Both in vitro and in vivo models demonstrated that PLOD3 enhances CRC cell proliferation, invasion, and migration. Furthermore, through mechanistic studies, TM9SF4 was identified as a protein that interacts with PLOD3 and contributes to CRC progression by promoting autophagy. Additionally, PLOD3 could be secreted by CRC cells and secreted PLOD3 could promote CRC cells migration and invasion. These results demonstrated that PLOD3 promotes CRC progression through the PLOD3/TM9SF4 axis and could be a potential biomarker and treatment target for CRC.

Comprehensive analysis and validation of autophagy-related gene in rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is a chronic autoimmune disease in which autophagy is pivotal in its pathogenesis. This study aims to identify autophagy-related genes associated with RA and investigate their functional roles.

Methods

We performed mRNA sequencing to identify differentially expressed genes (DEGs) between RA and osteoarthritis (OA) and intersected these with autophagy-related genes to obtain autophagy-related DEGs (ARDEGs) in RA. Bioinformatics and machine learning approaches were used to identify key biomarkers. Functional experiments, including real-time cellular analysis (RTCA), scratch healing, and flow cytometry, were conducted to examine the effects of gene silencing on the proliferation and migration of MH7A cells.

Results

A total of 37 ARDEGs were identified in RA. Through bioinformatics analysis, interferon regulatory factor 4 (IRF4) emerged as a key hub gene, with its high expression confirmed in RA synovial tissues and RA FLS cells. IRF4 knockdown inhibited the proliferation and migration and promoted the death of MH7A cells.

Conclusion

IRF4 is an autophagy-related diagnostic biomarker for RA. Targeting IRF4 could serve as a potential diagnostic and therapeutic strategy for RA, although further clinical studies are required to validate its effectiveness.

Monitoring Autophagy in Human Aging: Key Cell Models and Insights

Autophagy, a key cellular degradation and recycling pathway, is critical for maintaining cellular homeostasis and responding to metabolic and environmental stress. Evidence for age-related autophagic dysfunction and its implications in chronic age-related diseases including neurodegeneration is accumulating. However, as a complex, multi-step process, autophagy can be challenging to measure, particularly in humans and human aging- and disease-relevant models. This review describes the links between macroautophagy, aging, and chronic age-related diseases. We present three novel human cell models, peripheral blood mononuclear cells (PBMCs), primary dermal fibroblasts (PDFs), and induced neurons (iNs), which serve as essential tools for studying autophagy flux and assessing its potential as a biomarker for aging. Unlike traditional models, these cell models retain age- and disease-associated molecular signatures, enhancing their relevance for human studies. The development of robust tools and methodologies for measuring autophagy flux in human cell models holds promise for advancing our understanding of autophagy's role in aging and age-related diseases, ultimately facilitating the discovery of therapies to enhance health outcomes.

Synaptic plasticity and neuroprotection: The molecular impact of flavonoids on neurodegenerative disease progression

Flavonoids are a broad family of polyphenolic chemicals that are present in a wide variety of fruits, vegetables, and medicinal plants. Because of their neuroprotective qualities, flavonoids have attracted a lot of interest. The potential of flavonoids to control synaptic plasticity-a crucial process underlying memory, learning, and cognitive function-is becoming more and more clear. Dysregulation of synaptic plasticity is a feature of neurodegenerative diseases such as amyotrophic lateral sclerosis (0.4 %), Parkinson's (1-2 %), Alzheimer's (5-7 %), and Huntington's ((0.2 %)). This review discusses the molecular mechanisms via which flavonoids influence synaptic plasticity as well as their therapeutic potential in neurodegenerative diseases. Flavonoids modulate key signaling pathways such as MAPK/ERK and PI3K/Akt/mTOR to support neuroprotection, synaptic plasticity, and neuronal health, while also influencing neurotrophic factors (BDNF, NGF) and their receptors (TrkB, TrkA). They regulate neurotransmitter receptors like GABA, AMPA, and NMDA to balance excitatory and inhibitory transmission, and exert antioxidant effects via the Nrf2-ARE pathway and anti-inflammatory actions by inhibiting NF-κB signaling, highlighting their potential for treating neurodegenerative diseases. These varied reactions support the preservation of synapse function and neuronal integrity in the face of neurodegenerative insults. Flavonoids can reduce the symptoms of neurodegeneration, prevent synaptic loss, and enhance cognitive function, according to experimental studies. However, there are still obstacles to using these findings in clinical settings, such as limited bioavailability and the need for consistent dose. The focus of future research should be on improving flavonoid delivery systems and combining them with conventional medications.

How does autophagy impact neurological function?

Autophagies describe a set of processes in which cells degrade their cytoplasmic contents via various routes that terminate with the lysosome. In macroautophagy (the focus of this review, henceforth autophagy), cytoplasmic contents, including misfolded proteins, protein complexes, dysfunctional organelles, and various pathogens, are captured within double membranes called autophagosomes, which ultimately fuse with lysosomes, after which their contents are degraded. Autophagy is important in maintaining neuronal and glial function; consequently, disrupted autophagy is associated with various neurologic diseases. This review provides a broad perspective on the roles of autophagy in the CNS, highlighting recent literature that furthers our understanding of the multifaceted role of autophagy in maintaining a healthy nervous system.

A primary cilia-autophagy axis in hippocampal neurons is essential to maintain cognitive resilience

Blood-borne factors are essential to maintain neuronal synaptic plasticity and cognitive resilience throughout life. One such factor is osteocalcin (OCN), a hormone produced by osteoblasts that influences multiple physiological processes, including hippocampal neuronal homeostasis. However, the mechanism through which this blood-borne factor communicates with neurons remains unclear. Here we show the importance of a core primary cilium (PC) protein-autophagy axis in mediating the effects of OCN. We found that the OCN receptor GPR158 is present at the PC of hippocampal neurons and mediates the regulation of autophagy machinery by OCN. During aging, autophagy and PC core proteins are reduced in neurons, and restoring their levels is sufficient to improve cognitive impairments in aged mice. Mechanistically, the induction of this axis by OCN is dependent on the PC-dependent cAMP response element-binding protein signaling pathway. Altogether, this study demonstrates that the PC-autophagy axis is a gateway to mediate communication between blood-borne factors and neurons, and it advances understanding of the mechanisms involved in age-related cognitive decline.

Cargo hitchhiking autophagy - a hybrid autophagy pathway utilized in yeast

Macroautophagy is a catabolic process that maintains cellular homeostasis by recycling intracellular material through the use of double-membrane vesicles called autophagosomes. In turn, autophagosomes fuse with vacuoles (in yeast and plants) or lysosomes (in metazoans), where resident hydrolases degrade the cargo. Given the conservation of autophagy, Saccharomyces cerevisiae is a valuable model organism for deciphering molecular details that define macroautophagy pathways. In yeast, macroautophagic pathways fall into two subclasses: selective and nonselective (bulk) autophagy. Bulk autophagy is predominantly upregulated following TORC1 inhibition, triggered by nutrient stress, and degrades superfluous random cytosolic proteins and organelles. In contrast, selective autophagy pathways maintain cellular homeostasis when TORC1 is active by degrading damaged organelles and dysfunctional proteins. Here, selective autophagy receptors mediate cargo delivery to the vacuole. Now, two groups have discovered a new hybrid autophagy mechanism, coined cargo hitchhiking autophagy (CHA), that uses autophagic receptor proteins to deliver selected cargo to phagophores built in response to nutrient stress for the random destruction of cytosolic contents. In CHA, various autophagic receptors link their cargos to lipidated Atg8, located on growing phagophores. In addition, the sorting nexin heterodimer Snx4-Atg20 assists in the degradation of cargo during CHA, possibly by aiding the delivery of cytoplasmic cargos to phagophores and/or by delaying the closure of expanding phagophores. This review will outline this new mechanism, also known as Snx4-assisted autophagy, that degrades an assortment of cargos in yeast, including transcription factors, glycogen, and a subset of ribosomal proteins.

Contactin -Associated protein1 Regulates Autophagy by Modulating the PI3K/AKT/mTOR Signaling Pathway and ATG4B Levels in Vitro and in Vivo

Contactin-associated protein1 (Caspr1) plays an important role in the formation and stability of myelinated axons. In Caspr1 mutant mice, autophagy-related structures accumulate in neurons, causing axonal degeneration; however, the mechanism by which Caspr1 regulates autophagy remains unknown. To illustrate the mechanism of Caspr1 in autophagy process, we demonstrated that Caspr1 knockout in primary neurons from mice along with human cell lines, HEK-293 and HeLa, induced autophagy by downregulating the PI3K/AKT/mTOR signaling pathway to promote the conversion of microtubule-associated protein light chain 3 I (LC3-I) to LC3-II. In contrast, Caspr1 overexpression in cells contributed to the upregulation of this signaling pathway. We also demonstrated that Caspr1 knockout led to increased LC3-I protein expression in mice. In addition, Caspr1 could inhibit the expression of autophagy-related 4B cysteine peptidase (ATG4B) protein by directly binding to ATG4B in overexpressed Caspr1 cells. Intriguingly, we found an accumulation of ATG4B in the Golgi apparatuses of cells overexpressing Caspr1; therefore, we speculate that Caspr1 may restrict ATG4 secretion from the Golgi apparatus to the cytoplasm. Collectively, our results indicate that Caspr1 may regulate autophagy by modulating the PI3K/AKT/mTOR signaling pathway and the levels of ATG4 protein, both in vitro and in vivo. Thus, Caspr1 can be a potential therapeutic target in axonal damage and demyelinating diseases.

Multimodal insights into adult neurogenesis: An integrative review of multi-omics approaches

Adult neural stem cells divide to produce neurons that migrate to preexisting neuronal circuits in a process named adult neurogenesis. Adult neurogenesis is one of the most exciting areas of current neuroscience, and it may be involved in a range of brain functions, including cognition, learning, memory, and social and behavior changes. While there is a growing number of multi-omics studies on adult neurogenesis, generalized analyses from a multi-omics perspective are lacking. In this review, we summarize studies related to genomics, metabolomics, proteomics, epigenomics, transcriptomics, and microbiomics of adult neurogenesis, and then discuss their future research priorities and potential neighborhoods. This will provide theoretical guidance and new directions for future research on adult neurogenesis.

Determination of Trends Underlying Aspartic Acid Isomerization in Intact Proteins Reveals Unusually Rapid Isomerization of Tau

Spontaneous chemical modifications in long-lived proteins can potentially change protein structure in ways that impact proteostasis and cellular health. For example, isomerization of aspartic acid interferes with protein turnover and is anticorrelated with cognitive acuity in Alzheimer's disease. However, few isomerization rates have been determined for Asp residues in intact proteins. To remedy this deficiency, we used protein extracts from SH-SY5Y neuroblastoma cells as a source of a complex, brain-relevant proteome with no baseline isomerization. Cell lysates were aged in vitro to generate isomers, and extracted proteins were analyzed by data-independent acquisition (DIA) liquid chromatography-mass spectrometry (LC-MS). Although no Asp isomers were detected at day 0, isomerization increased over time and was quantifiable for 105 proteins by day 50. Data analysis revealed that the isomerization rate is influenced by both primary sequence and secondary structure, suggesting that steric hindrance and backbone rigidity modulate isomerization. Additionally, we examined lysates extracted under gentle conditions to preserve protein complexes and found that protein-protein interactions often slow isomerization. Base catalysis was explored as a means to accelerate Asp isomerization due to findings of accelerated asparagine deamidation. However, no substantial rate enhancement was found for isomerization, suggesting fundamental differences in acid-base chemistry. With an enhanced understanding of Asp isomerization in proteins in general, we next sought to better understand Asp isomerization in tau. In vitro aging of monomeric and aggregated recombinant tau revealed that tau isomerizes significantly faster than any similar protein within our data set, which is likely related to its correlation with cognition in Alzheimer's disease.

Vinpocetine and Lactobacillus Attenuated Rotenone-Induced Parkinson's Disease and Restored Dopamine Synthesis in Rats through Modulation of Oxidative Stress, Neuroinflammation, and Lewy Bodies Inclusion

Parkinson's disease (PD) is the main neurodegenerative disorder affecting motor activity, there are different pathophysiological pathways contributing to its development including oxidative stress, neuroinflammation, Lewy's bodies accumulation, and impaired autophagy. Vinpocetine is an herbal extract with antioxidant and anti-inflammatory activities that may counteract pathophysiologic neurodegeneration pathways. Moreover, Lactobacillus is a probiotic that can modulate the gut-brain axis and provide the body with the needed precursors of antioxidants and anti-inflammatory mediators. In the current study PD was induced experimentally in Sprague Dawley rats with rotenone (2.5 mg/kg, i.p, daily) for 60 days, vinpocetine; Vinpo (20 mg/kg, orally, daily) and Lactobacillus; Lacto (2.7 × 108 CFU/ml, orally, daily) were applied as protective treatment. Vinpocetine and Lactobacillus treatment significantly ameliorated motor function by increasing distance traveled and rearing frequency in the open field test with a concomitant increase in falling time from both the accelerating rotarod and the wire screen test. Moreover, vinpocetine and Lactobacillus treatment upregulates tyrosine hydroxylase expression (the rate-limiting enzyme in dopamine synthesis), leading to enhanced dopamine synthesis and improved dopaminergic function with regression of histopathological hallmarks. Antioxidant GSH levels were significantly increased after vinpocetine and Lactobacillus treatment with a significant decrease in MDA content in brain homogenates. Furthermore, vinpocetine and Lactobacillus treatment significantly decreased striatal inflammatory markers; nitrite, IL-1β and TNF-α. Proteinopathies were regressed with a substantial decrease in striatal α-synuclein and tau content. In conclusion, vinpocetine and Lactobacillus treatment reduced rotenone neurotoxicity with improved dopamine release and motor activity with correction of oxidative burden, neuro-inflammation, and proteinopathy.

ATG9 promotes autophagosome formation through interaction with LC3

The autophagosome is a double-membrane organelle that executes macroautophagy. Previous studies have shown that the autophagosome formation is driven by autophagy-related genes, among which ATG9 is the only conserved transmembrane protein and has been shown to play a critical role in the autophagosome formation. However, how ATG9 binds to the growing autophagosome membrane has remained uncertain. Herein, we report that ATG9 binds to LC3, an essential membrane component of the autophagosome, thereby allowing ATG9 to incorporate into the autophagosome membrane. Mechanistically, we show that ATG9 interacts with LC3 through its UIM motives, which bind to the UDS site of LC3. Interrupting such UIM-UDS interaction abolishes the autophagosome association of ATG9 and suppresses the autophagosome formation. Collectively, our findings reveal a novel mechanism regulating autophagosome biogenesis and suggest that the interaction of ATG9 with LC3 is critical for ATG9 binding to the growing autophagosome membrane.

Cuproptosis: A new mechanism for anti-tumour therapy

As an indispensable trace metal element in the organism, copper acts as a key catalytic cofactor in a wide range of biological processes. Copper homeostasis disorders can be caused by either copper excess or deficiency, and copper homeostasis disorders will affect the normal physiological functions of cells and induce cell death through a variety of mechanisms, such as the emerging cuproptosis model. The imbalance of copper homeostasis will lead to the occurrence of cancer, and copper is a key factor in cell signalling, so copper is involved in the development of cancer by promoting cell proliferation, angiogenesis and metastasis, etc. The therapeutic role of Cuproptosis as a hotspot of research in cancer has also attracted much attention. Therefore, this paper comprehensively searches the literature to review the roles and mechanisms of Cuproptosis in the treatment of malignant tumours, aiming to provide new insights into the role and mechanism of Cuproptosis in anti-malignant tumour therapy and present novel ideas and methods.

Bombyx mori PAT4 gene inhibits BmNPV infection and replication through autophagy

Proton-assisted amino acid transporter 4 (PAT4) is a member of the solute carrier (SLC) 36 family, which mediates the transmembrane transport of amino acids and their derivatives. However, the function of PAT4 in Bombyx mori is not clear. In this study, BmPAT4 was cloned and identified using PCR technology. Its open reading frame (ORF) includes 1,395 bp, encoding 464 amino acid (Aa). Moreover, the sequence of BmPAT4 has the highest similarity with wild Bombyx.mandarina, Spodoptera frugiperda and Spodoptera litura, and it has ten transmembrane domains. BmPAT4 was localized in the cell membrane and expressed in all tissues of the silkworm. After Bombyx mori nuclear polyhedrosis virus (BmNPV) infection, the expression of BmPAT4 in midgut, hemolymph and fat body was significantly up-regulated. In addition, overexpression of BmPAT4 in BmN cells could significantly inhibit the proliferation of BmNPV, and the expression of several genes in autophagy pathway decreased significantly. On the contrary, down-regulation of BmPAT4 expression by RNA interference can promote BmNPV replication and proliferation, and the expression of key genes in autophagy pathway is significantly increased. This is the first time to report that BmPAT4 has an antiviral effect in silkworm. Moreover, the silkworm activates BmTORC1 via BmPAT4, which inhibits autophagy in silkworm cells, resulting in a lack of energy and raw materials for BmNPV infection and replication in cells.

Periodontopathogen-Related Cell Autophagy-A Double-Edged Sword

The periodontium is a highly organized ecosystem, and the imbalance between oral microorganisms and host defense leads to periodontal diseases. The periodontal pathogens, mainly Gram-negative anaerobic bacteria, colonize the periodontal niches or enter the blood circulation, resulting in periodontal tissue destruction and distal organ damage. This phenomenon links periodontitis with various systemic conditions, including cardiovascular diseases, malignant tumors, steatohepatitis, and Alzheimer's disease. Autophagy is an evolutionarily conserved cellular self-degradation process essential for eliminating internalized pathogens. Nowadays, increasing studies have been carried out in cells derived from periodontal tissues, immune system, and distant organs to investigate the relationship between periodontal pathogen infection and autophagy-related activities. On one hand, as a vital part of innate and adaptive immunity, autophagy actively participates in host resistance to periodontal bacterial infection. On the other, certain periodontal pathogens exploit autophagic vesicles or pathways to evade immune surveillance, therefore achieving survival within host cells. This review provides an overview of the autophagy process and focuses on periodontopathogen-related autophagy and their involvements in cells of different tissue origins, so as to comprehensively understand the role of autophagy in the occurrence and development of periodontal diseases and various periodontitis-associated systemic illnesses.

Retinal Pigment Epithelium Under Oxidative Stress: Chaperoning Autophagy and Beyond

The structural and functional integrity of the retinal pigment epithelium (RPE) plays a key role in the normal functioning of the visual system. RPE cells are characterized by an efficient system of photoreceptor outer segment phagocytosis, high metabolic activity, and risk of oxidative damage. RPE dysfunction is a common pathological feature in various retinal diseases. Dysregulation of RPE cell proteostasis and redox homeostasis is accompanied by increased reactive oxygen species generation during the impairment of phagocytosis, lysosomal and mitochondrial failure, and an accumulation of waste lipidic and protein aggregates. They are the inducers of RPE dysfunction and can trigger specific pathways of cell death. Autophagy serves as important mechanism in the endogenous defense system, controlling RPE homeostasis and survival under normal conditions and cellular responses under stress conditions through the degradation of intracellular components. Impairment of the autophagy process itself can result in cell death. In this review, we summarize the classical types of oxidative stress-induced autophagy in the RPE with an emphasis on autophagy mediated by molecular chaperones. Heat shock proteins, which represent hubs connecting the life supporting pathways of RPE cells, play a special role in these mechanisms. Regulation of oxidative stress-counteracting autophagy is an essential strategy for protecting the RPE against pathological damage when preventing retinal degenerative disease progression.

Canonical and noncanonical autophagy: involvement in Parkinson's disease

Autophagy is the major degradation process in cells and is involved in a variety of physiological and pathological functions. While macroautophagy, which employs a series of molecular cascades to form ATG8-coated double membrane autophagosomes for degradation, remains the well-known type of canonical autophagy, microautophagy and chaperon-mediated autophagy have also been characterized. On the other hand, recent studies have focused on the functions of autophagy proteins beyond intracellular degradation, including noncanonical autophagy, also known as the conjugation of ATG8 to single membranes (CASM), and autophagy-related extracellular secretion. In particular, CASM is unique in that it does not require autophagy upstream mechanisms, while the ATG8 conjugation system is involved in a manner different from canonical autophagy. There have been many reports on the involvement of these autophagy-related mechanisms in neurodegenerative diseases, with Parkinson's disease (PD) receiving particular attention because of the important roles of several causative and risk genes, including LRRK2. In this review, we will summarize and discuss the contributions of canonical and noncanonical autophagy to cellular functions, with a special focus on the pathogenesis of PD.

A novel lncRNA FAM151B-DT regulates autophagy and degradation of aggregation prone proteins

Neurodegenerative diseases share common features of protein aggregation along with other pleiotropic traits, including shifts in transcriptional patterns, neuroinflammation, disruptions in synaptic signaling, mitochondrial dysfunction, oxidative stress, and impaired clearance mechanisms like autophagy. However, key regulators of these pleotropic traits have yet to be identified. Here, we discovered a novel long non-coding RNA (lncRNA), FAM151B-DT, that is reduced in a stem cell model of frontotemporal dementia with tau inclusions (FTLD-tau) and in brains from FTLD-tau, progressive supranuclear palsy, Alzheimer's disease, and Parkinson's disease patients. We show that silencing FAM151B-DT in vitro is sufficient to enhance tau aggregation. To begin to understand the mechanism by which FAM151B-DT mediates tau aggregation and contributes to several neurodegenerative diseases, we deeply characterized this novel lncRNA and found that FAM151B-DT resides in the cytoplasm where it interacts with tau, α-synuclein, HSC70, and other proteins enriched in protein homeostasis. When silenced, FAM151B-DT blocks autophagy, leading to the accumulation of tau and α-synuclein. Importantly, we discovered that increasing FAM151B-DT expression is sufficient to promote autophagic flux, reduce phospho-tau and α-synuclein, and reduce tau aggregation. Overall, these findings pave the way for further exploration of FAM151B-DT as a promising molecular target for several neurodegenerative diseases.

Identification and preliminary validation of biomarkers associated with mitochondrial and programmed cell death in pre-eclampsia

Background

The involvement of mitochondrial and programmed cell death (mtPCD)-related genes in the pathogenesis of pre-eclampsia (PE) remains inadequately characterized.

Methods

This study explores the role of mtPCD genes in PE through bioinformatics and experimental approaches. Differentially expressed mtPCD genes were identified as potential biomarkers from the GSE10588 and GSE98224 datasets and subsequently validated. Hub genes were determined using support vector machine, least absolute shrinkage and selection operator, and Boruta based on consistent expression profiles. Their performance was assessed through nomogram and artificial neural network models. Biomarkers were subjected to localization, functional annotation, regulatory network analysis, and drug prediction. Clinical validation was conducted via real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence, and Western blot.

Results

Four genes [solute carrier family 25 member 5 (SLC25A5), acyl-CoA synthetase family member 2 (ACSF2), mitochondrial fission factor (MFF), and phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1)] were identified as biomarkers distinguishing PE from normal controls. Functional analysis indicated their involvement in various biological pathways. Immune analysis revealed associations between biomarkers and immune cell activity. A regulatory network was informed by biomarker expression and database predictions, in which KCNQ1OT1 modulates ACSF2 expression via hsa-miR-200b-3p. Drug predictions, including clodronic acid, were also proposed. Immunofluorescence, RT-qPCR, and Western blot confirmed reduced expression of SLC25A5, MFF, and PMAIP1 in PE, whereas ACSF2 was significantly upregulated.

Conclusion

These four mtPCD-related biomarkers may play a pivotal role in PE pathogenesis, offering new perspectives on the disease's diagnostic and mechanistic pathways.

The Role of Autophagy in Copper-Induced Apoptosis and Developmental Neurotoxicity in SH-SY5Y Cells

Copper (Cu) is a global environmental pollutant that poses a serious threat to humans and ecosystems. Copper induces developmental neurotoxicity, but the underlying molecular mechanisms are unknown. Neurons are nonrenewable, and they are unable to mitigate the excessive accumulation of pathological proteins and organelles in cells, which can be ameliorated by autophagic degradation. In this study, we established an in vitro model of Cu2+-exposed (0, 15, 30, 60 and 120 μM) SH-SY5Y cells to explore the role of autophagy in copper-induced developmental neurotoxicity. The results showed that copper resulted in the reduction and shortening of neural synapses in differentiated cultured SH-SY5Y cells, a downregulated Wnt signaling pathway, and nuclear translocation of β-catenin. Exposure to Cu2+ increased autophagosome accumulation and autophagic flux blockage in terms of increased sequestosome 1 (p62/SQSTM1) and microtubule-associated protein 1 light chain 3B (LC3B) II/LC3BI expressions and inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR pathway. Furthermore, copper induced apoptosis, characterized by increased expressions of Bcl2 X protein (Bax), caspase 3, and Poly (ADP-ribose) polymerase (PARP) and decreased expression of B-cell lymphoma 2 (Bcl2). Compared with the 120 μM Cu2+ exposure group alone, autophagy activator rapamycin pretreatment increased expression of Wnt and β-catenin nuclear translocation, decreased expression of LC3BII/LC3BI and p62, as well as upregulated expression of Bcl2 and downregulated expressions of caspase 3 and PARP. In contrast, after autophagy inhibitor chloroquine pretreatment, expressions of Wnt and β-catenin nuclear translocation were decreased, expression levels of LC3BII/LC3BI and p62 were upregulated, expression of Bcl2 was decreased, while expression levels of caspase 3, Bax, and PARP were increased. In conclusion, the study demonstrated that autophagosome accumulation and autophagic flux blockage were associated with copper-induced developmental neurotoxicity via the Wnt signaling pathway, which might deepen the understanding of the developmental neurotoxicity mechanism of environmental copper exposure.

Autophagy, aging, and age-related neurodegeneration

Autophagy is a conserved mechanism that degrades damaged or superfluous cellular contents and enables nutrient recycling under starvation conditions. Many neurodegeneration-associated proteins are autophagy substrates, and autophagy upregulation ameliorates disease in many animal models of neurodegeneration by enhancing the clearance of toxic proteins, proinflammatory molecules, and dysfunctional organelles. Autophagy inhibition also induces neuronal and glial senescence, a phenomenon that occurs with increasing age in non-diseased brains as well as in response to neurodegeneration-associated stresses. However, aging and many neurodegeneration-associated proteins and mutations impair autophagy. This creates a potentially detrimental feedback loop whereby the accumulation of these disease-associated proteins impairs their autophagic clearance, facilitating their further accumulation and aggregation. Thus, understanding how autophagy interacts with aging, senescence, and neurodegenerative diseases in a temporal, cellular, and genetic context is important for the future clinical application of autophagy-modulating therapies in aging and neurodegeneration.

Noncoding RNA Terc-53 and hyaluronan receptor Hmmr regulate aging in mice

One of the basic questions in the aging field is whether there is a fundamental difference between the aging of lower invertebrates and mammals. A major difference between the lower invertebrates and mammals is the abundancy of noncoding RNAs, most of which are not conserved. We have previously identified a noncoding RNA Terc-53 that is derived from the RNA component of telomerase Terc. To study its physiological functions, we generated two transgenic mouse models overexpressing the RNA in wild-type and early-aging Terc-/- backgrounds. Terc-53 mice showed age-related cognition decline and shortened life span, even though no developmental defects or physiological abnormality at an early age was observed, indicating its involvement in normal aging of mammals. Subsequent mechanistic study identified hyaluronan-mediated motility receptor (Hmmr) as the main effector of Terc-53. Terc-53 mediates the degradation of Hmmr, leading to an increase of inflammation in the affected tissues, accelerating organismal aging. adeno-associated virus delivered supplementation of Hmmr in the hippocampus reversed the cognition decline in Terc-53 transgenic mice. Neither Terc-53 nor Hmmr has homologs in C. elegans. Neither do arthropods express hyaluronan. These findings demonstrate the complexity of aging in mammals and open new paths for exploring noncoding RNA and Hmmr as means of treating age-related physical debilities and improving healthspan.

Unknown roles of tau pathology in neurological disorders. Challenges and new perspectives

Aging presents progressive changes that increase the susceptibility of the central nervous system (CNS) to suffer neurological disorders (NDs). Several studies have reported that an aged brain suffering from NDs shows the presence of pathological forms of tau protein, a microtubule accessory protein (MAP) critical for neuronal function. In this context, accumulative evidence has shown a pivotal contribution of pathological forms of tau to Alzheimer's disease (AD) and tauopathies. However, current investigations have implicated tau toxicity in other NDs that affect the central nervous system (CNS), including Parkinson's disease (PD), Huntington's disease (HD), Traumatic brain injury (TBI), Multiple sclerosis (MS), and Amyotrophic lateral sclerosis (ALS). These diseases are long-term acquired, affecting essential functions such as motor movement, cognition, hearing, and vision. Previous evidence indicated that toxic forms of tau do not have a critical contribution to the genesis or progression of these diseases. However, recent studies have shown that these tau forms contribute to neuronal dysfunction, inflammation, oxidative damage, and mitochondrial impairment events that contribute to the pathogenesis of these NDs. Recent studies have suggested that these neuropathologies could be associated with a prion-like behavior of tau, which induces a pathological dissemination of these toxic protein forms to different brain areas. Moreover, it has been suggested that this toxic propagation of tau from neurons into neighboring cells impairs the function of glial cells, oligodendrocytes, and endothelial cells by affecting metabolic function and mitochondrial health and inducing oxidative damage by tau pathology. Therefore, in this review, we will discuss current evidence demonstrating the critical role of toxic tau forms on NDs not related to AD and how its propagation and induced-bioenergetics failure may contribute to the pathogenic mechanism present in these NDs.