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The crosstalk between clathrin-mediated endocytosis (CME) and the autophagy pathway has been reported in mammals; however, the interconnection of CME with autophagy has not been established in plants. Here, we report that the Arabidopsis CLATHRIN LIGHT CHAIN (CLC) subunit 2 and 3 double mutant, clc2-1 clc3-1, phenocopies Arabidopsis AUTOPHAGY-RELATED GENE (ATG) mutants in both autoimmunity and nutrient sensitivity. Accordingly, the autophagy pathway is significantly compromised in the clc2-1 clc3-1 mutant. Interestingly, multiple assays demonstrate that CLC2 directly interacts with ATG8h/ATG8i in a domain-specific manner. As expected, both GFP-ATG8h/GFP-ATG8i and CLC2-GFP are subjected to autophagic degradation, and degradation of GFP-ATG8h is significantly reduced in the clc2-1 clc3-1 mutant. Notably, simultaneous knockout of ATG8h and ATG8i by CRISPR-Cas9 results in enhanced resistance against Golovinomyces cichoracearum, supporting the functional relevance of the CLC2-ATG8h/8i interactions. In conclusion, our results reveal a link between the function of CLCs and the autophagy pathway in Arabidopsis.

Understanding the normal function of the Huntingtin (HTT) protein is of significance in the design and implementation of therapeutic strategies for Huntington's disease (HD). Expansion of the CAG repeat in the HTT gene, encoding an expanded polyglutamine (polyQ) repeat within the HTT protein, causes HD and may compromise HTT's normal activity contributing to HD pathology. Here, we investigated the previously defined role of HTT in autophagy specifically through studying HTT's association with ubiquitin. We find that HTT interacts directly with ubiquitin in vitro. Tandem affinity purification was used to identify ubiquitinated and ubiquitin-associated proteins that copurify with a HTT N-terminal fragment under basal conditions. Copurification is enhanced by HTT polyQ expansion and reduced by mimicking HTT serine 421 phosphorylation. The identified HTT-interacting proteins include RNA-binding proteins (RBPs) involved in mRNA translation, proteins enriched in stress granules, the nuclear proteome, the defective ribosomal products (DRiPs) proteome and the brain-derived autophagosomal proteome. To determine whether the proteins interacting with HTT are autophagic targets, HTT knockout (KO) cells and immunoprecipitation of lysosomes were used to investigate autophagy in the absence of HTT. HTT KO was associated with reduced abundance of mitochondrial proteins in the lysosome, indicating a potential compromise in basal mitophagy, and increased lysosomal abundance of RBPs which may result from compensatory up-regulation of starvation-induced macroautophagy. We suggest HTT is critical for appropriate basal clearance of mitochondrial proteins and RBPs, hence reduced HTT proteostatic function with mutation may contribute to the neuropathology of HD.

The etiology of preeclampsia (PE), a severe complication of pregnancy with several clinical manifestations and a high incidence of maternal and fetal morbidity and mortality, remains unclear. This issue is a major hurdle for effective treatment strategies. We recently demonstrated that PE exhibits an Alzheimer-like etiology of impaired autophagy and proteinopathy in the placenta. Targeting of these pathological pathways may be a novel therapeutic strategy for PE. Stimulation of autophagy with the natural disaccharide trehalose and its lacto analog lactotrehalose in hypoxia-exposed primary human trophoblasts restored autophagy, inhibited the accumulation of toxic protein aggregates, and restored the ultrastructural features of autophagosomes and autolysosomes. Importantly, trehalose and lactotrehalose inhibited the onset of PE-like features in a humanized mouse model by normalizing autophagy and inhibiting protein aggregation in the placenta. These disaccharides restored the autophagy-lysosomal biogenesis machinery by increasing nuclear translocation of the master transcriptional regulator TFEB. RNA-seq analysis of the placentas of mice with PE indicated the normalization of the PE-associated transcriptome profile in response to trehalose and lactotrehalose. In summary, our results provide a novel molecular rationale for impaired autophagy and proteinopathy in patients with PE and identify treatment with trehalose and its lacto analog as promising therapeutic options for this severe pregnancy complication.

Glycosphingolipids (GSLs) are key constituents of membrane bilayers playing a role in structural integrity, cell signalling in microdomains, endosomes and lysosomes, and cell death pathways. Conversion of ceramide into GSLs is controlled by GCS (glucosylceramide synthase) and inhibitors of this enzyme for the treatment of lipid storage disorders and specific cancers. With a diverse range of functions attributed to GSLs, the ability of the GSC inhibitor, eliglustat, to reduce myeloma bone disease was investigated. In pre-clinical models of multiple myeloma, osteoclast-driven bone loss was reduced by eliglustat in a mechanistically separate manner to zoledronic acid, a bisphosphonate that prevents osteoclast-mediated bone destruction. Autophagic degradation of TNF receptor-associated factor 3 (TRAF3), a key step for osteoclast differentiation, was inhibited by eliglustat as evidenced by TRAF3 lysosomal and cytoplasmic accumulation. By altering GSL composition, eliglustat prevented lysosomal degradation whilst exogenous addition of missing GSLs rescued TRAF3 degradation to restore osteoclast formation in bone marrow cells from myeloma patients. This work highlights the clinical potential of eliglustat as a therapy for myeloma bone disease. Furthermore, using eliglustat as a lysosomal inhibitor in osteoclasts may widen its therapeutic uses to other bone disorders such as bone metastasis, osteoporosis and inflammatory bone loss.

Autophagy in eukaryotes functions to maintain homeostasis by degradation and recycling of long-lived and unwanted cellular materials. Autophagy plays important roles in pathogenicity of various fungal pathogens, suggesting that autophagy is a novel target for development of antifungal compounds. Here, we describe bioluminescence resonance energy transfer (BRET)-based high-throughput screening (HTS) strategy to identify compounds that inhibit fungal ATG4 cysteine protease-mediated cleavage of ATG8 that is critical for autophagosome formation. We identified ebselen (EB) and its analogs ebselen oxide (EO) and 2-(4-methylphenyl)-1,2-benzisothiazol-3(2H)-one (PT) as inhibitors of fungal pathogens Botrytis cinerea and Magnaporthe oryzae ATG4-mediated ATG8 processing. The EB and its analogs inhibit spore germination, hyphal development, and appressorium formation in Ascomycota pathogens, B. cinerea, M. oryzae, Sclerotinia sclerotiorum and Monilinia fructicola. Treatment with EB and its analogs significantly reduced fungal pathogenicity. Our findings provide molecular insights to develop the next generation of antifungal compounds by targeting autophagy in important fungal pathogens.

The covalent attachment of ubiquitin-like LC3 proteins (microtubule-associated proteins 1A/1B light chain 3) prepares the autophagic membrane for cargo recruitment. We resolve key steps in LC3 lipidation by combining molecular dynamics simulations and experiments in vitro and in cellulo. We show how the E3-like ligaseautophagy-related 12 (ATG12)-ATG5-ATG16L1 in complex with the E2-like conjugase ATG3 docks LC3 onto the membrane in three steps by (i) the phosphatidylinositol 3-phosphate effector protein WD repeat domain phosphoinositide-interacting protein 2 (WIPI2), (ii) helix α2 of ATG16L1, and (iii) a membrane-interacting surface of ATG3. Phosphatidylethanolamine (PE) lipids concentrate in a region around the thioester bond between ATG3 and LC3, highlighting residues with a possible role in the catalytic transfer of LC3 to PE, including two conserved histidines. In a near-complete pathway from the initial membrane recruitment to the LC3 lipidation reaction, the three-step targeting of the ATG12-ATG5-ATG16L1 machinery establishes a high level of regulatory control.

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in the development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health, and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from patients with PAH. Endothelial haploinsufficiency of RAB7 caused spontaneous pulmonary hypertension (PH) in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA-Seq, and RAB7-silenced ECs showed impaired angiogenesis and expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, suggesting inhibition of autophagy at the predegradation level. Furthermore, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in rats with chronic hypoxia/SU5416. In conclusion, we demonstrate for the first time to our knowledge the fundamental impairment of EC function by loss of RAB7, causing PH, and show RAB7 activation to be a potential therapeutic strategy in a preclinical model of PH.

Non-neovascular or dry age-related macular degeneration (AMD) is a multi-factorial disease with degeneration of the aging retinal-pigmented epithelium (RPE). Lysosomes play a crucial role in RPE health via phagocytosis and autophagy, which are regulated by transcription factor EB/E3 (TFEB/E3). Here, we find that increased AKT2 inhibits PGC-1α to downregulate SIRT5, which we identify as an AKT2 binding partner. Crosstalk between SIRT5 and AKT2 facilitates TFEB-dependent lysosomal function in the RPE. AKT2/SIRT5/TFEB pathway inhibition in the RPE induced lysosome/autophagy signaling abnormalities, disrupted mitochondrial function and induced release of debris contributing to drusen. Accordingly, AKT2 overexpression in the RPE caused a dry AMD-like phenotype in aging Akt2 KI mice, as evident from decline in retinal function. Importantly, we show that induced pluripotent stem cell-derived RPE encoding the major risk variant associated with AMD (complement factor H; CFH Y402H) express increased AKT2, impairing TFEB/TFE3-dependent lysosomal function. Collectively, these findings suggest that targeting the AKT2/SIRT5/TFEB pathway may be an effective therapy to delay the progression of dry AMD.

Autophagy is a form of programmed cell degradation that enables the maintenance of homeostasis in response to extracellular stress stimuli. Autophagy is primarily activated by starvation and mediates the degradation, removal, or recycling of cell cytoplasm, organelles, and intracellular components in eukaryotic cells. Autophagy is also involved in the pathogenesis of human diseases, including several cancers. Human uveal melanoma (UM) is the primary intraocular malignancy in adults and has an extremely poor prognosis; at present there are no effective therapies. Several studies have suggested that autophagy is important in UM. By understanding the mechanisms of activation of autophagy in UM it may be possible to develop biomarkers to provide more definitive disease prognoses and to identify potential drug targets for the development of new therapeutic strategies. This article reviews the current information regarding autophagy in UM that could facilitate biomarker and drug development.

The pathways that induce macroautophagy (referred to as autophagy hereafter) in response to the stress of starvation are well conserved and essential under nutrient-limiting conditions. However, less is understood about the mechanisms that modulate the autophagy response. Here we present evidence that after induction of autophagy in budding yeast septin filaments rapidly assemble into discrete patches distributed along the cell cortex. These patches gradually mature over 12 h of nutrient deprivation to form extended structures around Atg9 membranes tethered at the cortical endoplasmic reticulum, a class of membranes that are limiting for autophagosome biogenesis. Loss of cortical septin structures alters the kinetics of autophagy activation and most dramatically extends the duration of the autophagy response. In wild-type cells, diffusion of Atg9 membranes at the cell cortex undergoes transient pauses that are dependent on septins, and septins at the bud neck block the diffusion of Atg9 membranes between mother and daughter cells. We conclude that septins reorganize at the cell cortex during autophagy to locally limit access of Atg9 membranes to autophagosome assembly sites, and thus modulate the autophagy response during nutrient deprivation.

Autophagy is a highly conserved 'self-digesting' mechanism used in eukaryotes to degrade and recycle cellular components by enclosing them in a double membrane compartment and delivering them to lytic organelles (lysosomes or vacuoles). Extensive studies in plants have revealed how autophagy is intricately linked to essential aspects of metabolism and growth, in both normal and stress conditions, including cellular and organelle homeostasis, nutrient recycling, development, responses to biotic and abiotic stresses, senescence and cell death. However, knowledge regarding autophagic processes in other photosynthetic organisms remains limited. In this review, we attempt to summarize the current understanding of autophagy in algae from a metabolic, molecular and evolutionary perspective. We focus on the composition and conservation of the autophagy molecular machinery in eukaryotes and discuss the role of autophagy in metabolic regulation, cellular homeostasis and stress adaptation in algae. This article is part of the theme issue 'The evolution of plant metabolism'. [ABSTRACT FROM AUTHOR]

BACKGROUND:Autophagy and ferroptosis play important roles in the development of chronic kidney disease, but the molecular mechanisms and gene targets related to autophagy and ferroptosis in renal tissue of chronic kidney disease are still unclear. OBJECTIVE:To screen differentially expressed genes in chronic kidney disease-related datasets based on bioinformatics, and to explore potential key biomarkers suitable for screening renal function progression in patients with chronic kidney disease. METHODS: The GSE137570 dataset was obtained from GEO database to screen the differentially expressed genes by Networkanalyst database analysis. Ferroptosis and autophagy related targets were obtained by OMIM, GENECARD, FerrDb and HAMdb databases. The respective data were intersected to obtain autophagy-ferroptosis related differentially expressed genes in chronic kidney disease for parallel enrichment analysis. The STRING website was used to construct the protein-protein interaction network of differentially expressed genes, which was imported into Cytoscape software and analyzed by MCODEand Cytohubba plug-in to screen potential core targets. Enrichment analysis was performed to obtain the functions of these potential core targets. In the in vitro experiment, mouse renal tubular epithelial cells were divided into two groups:the control group received no intervention, while the model group was stimulated with 5 ng/mL transforming growth factor β1 for 24 hours to induce mesenchymal transformation of renal tubular epithelial cells. Flow cytometry was used to measure the levels of reactive oxygen species and changes in mitochondrial membrane potential in the cells. RT-PCR was employed to assess ferroptosis, autophagy-related markers, and the mRNA expression of potential core targets in the cells. RESULTS AND CONCLUSION:After screening the GSE137570 dataset, a total of 480 differentially expressed genes were obtained, including 104 upregulated genes and 376 downregulated genes (log2| (FC)|＞1, P＜0. 05). There were 562 ferroptosis-related targets and 1 266 autophagy-related targets obtained from the OMIM, GENECARD, FerrDb, and HAMdb databases. Intersection of differentially expressed genes with ferroptosis-and autophagy-related targets yielded15 ferroptosis-related targets and 18 autophagy-related targets, respectively. The enrichment analysis results indicate that ferroptosis-related differentially expressed genes are primarily involved in biological processes such as sulfur amino acid metabolism, neutrophil degranulation, and ferroptosis signaling pathways. Autophagy-related differentially expressed genes are mainly enriched in biological processes such as platelet degranulation, extracellular matrix degradation, and receptor tyrosine kinase signaling. After screened by MCODE and CytoHubba, key genes were identified in the protein-protein interaction network, including CD44, ALB, TIMP1, PLG, CCL2, and DPP4. Immune infiltration analysis results indicate that immune cells such as B cells, CD4+T cells, NK cells, and monocytes show significant differential expression in renal tissue after chronic kidney disease, and the core targets are also significantly correlated with these immune cells (P＜0. 05). The results of receiver operator characteristic curve analysis further demonstrate that the pathological progression of chronic kidney disease can be effectively diagnosed by CD44, ALB, TIMP1, PLG, CCL2, and DPP4. Single-cell sequencing results show that, except for PLG, the expression of target genes in the renal tissue of mice in each model group is generally consistent with the results of this experiment. RT-PCR results demonstrate that, for the validation of autophagy and ferroptosis phenotypes, compared with the control group, the model group shows a significant decrease in mRNA expression of LC3B, Nrf2, and SLC7A11 (P＜0. 05), and a significant increase in P62 mRNA expression (P＜0. 05). Regarding the validation of potential core targets, compared with the control group, the model group exhibits a significant decrease in mRNA expression of ALB and PLG (P＜0. 05), and a significant increase in TIMP1 and CCL2 mRNA expression (P＜0. 05). Overall, these findings indicate that, through bioinformatics analysis and experimental validation, CD44, ALB, TIMP1, PLG, and CCL2 are abnormally expressed in the renal tissue of patients with chronic kidney disease, closely correlated with estimated glomerular filtration rate and tubulointerstitial fibrosis, and maybe play a predictive role in the progression of chronic kidney disease [ABSTRACT FROM AUTHOR]

Objectives: Endothelial-to-mesenchymal transition (EndoMT) is a significant biological phenomenon wherein endothelial cells undergo a loss of their endothelial traits and progressively acquire mesenchymal characteristics. Consequently, this transformation leads to both a compromised ability to maintain lumen permeability and alterations in vascular structure, which hampers the preservation of bloodbrain barrier integrity. This study aimed to investigate inflammation-induced EndoMT and its etiology, with the goal of impeding the infiltration of peripheral inflammation into the central nervous system. Materials and Methods: Lipolysaccharide (LPS) was administered intraperitoneally to mice several times to establish a chronic inflammatory model. A cellular inflammatory model was established by LPS in human brain microvascular endothelial cells (HBMECs). The mRNA expressions of inflammatory cytokines interleukin-1β (IL-1β) and IL-6 were detected by real-time polymerase chain reaction (PCR). Immunofluorescence staining of platelet endothelial cell adhesion molecule-1 (CD31) and alpha smooth muscle actin (α-SMA) was conducted to assess the level of EndoMT. The expression levels of Occludin, zona occludens protein 1 (ZO-1), Sestrin2, microtubule-associated protein1 light chain 3 (LC3) and inducible nitric oxide synthase (iNOS) were detected by western blotting. Results: LPS treatment induced the downregulation of ZO-1 and Occludin, which was accompanied by the elevated expressions of iNOS, α-SMA, Sestrin2 and LC3-II in the mouse cortex and HBMECs. Mechanistically, the knockdown of Sestrin2 in HBMECs exacerbated the EndoMT induced by LPS treatment, while the overexpression of Sestrin2 inhibited this process. Moreover, the induction of autophagy by rapamycin rescued the EndoMT induced by Sestrin2 knockdown. Conclusion: This study revealed that Sestrin2 inhibited endothelial inflammation and EndoMT via enhanced autophagy, which may provide a potential drug target for cerebrovascular inflammatory injury. [ABSTRACT FROM AUTHOR]

Sodium-glucose cotransporter 2 (SGLT2) inhibitors exert a distinctive pattern of direct biological effects on the heart and kidney under experimental conditions, but the meaningfulness of these signatures for patients with heart failure has not been fully defined. We performed the first mechanistic validation study of large-scale proteomics in a double-blind randomized trial of any treatment in patients with heart failure. In a discovery cohort from the EMPEROR (Empagliflozin Outcome Trial in Patients With Chronic Heart Failure and Reduced Ejection Fraction) program, we studied the effect of randomized treatment with placebo or empagliflozin on 1,283 circulating proteins in 1,134 patients with heart failure with a reduced or preserved ejection fraction. In a validation cohort, we expanded the number to 2,155 assessed proteins, which were measured in 1,120 EMPEROR participants who had not been studied previously. In the validation cohort, 25 proteins were the most differentially enriched by empagliflozin (ie, ≥15% between-group difference and false discovery rate <1% at 12 weeks with known effects on the heart or kidney): 1) 13 proteins promote autophagy and other cellular quality-control functions (IGFBP1, OTUB1, DNAJB1, DNAJC9, RBP2, IST1, HSPA8, H-FABP, FABP6, ATPIFI, TfR1, EPO, IGBP1); 2) 12 proteins enhance mitochondrial health and ATP production (UMtCK, TBCA, L-FABP, H-FABP, FABP5, FABP6, RBP2, IST1, HSPA8, ATPIFI, TfR1, EPO); 3) 7 proteins augment cellular iron mobilization or erythropoiesis (TfR1, EPO, IGBP1, ERMAP, UROD, ATPIF1, SNCA); 4) 3 proteins influence renal tubular sodium handling; and 5) 9 proteins have restorative effects in the heart or kidneys, with many proteins exerting effects in >1 domain. These biological signatures replicated those observed in our discovery cohort. When the threshold for a meaningful between-group difference was lowered to ≥10%, there were 58 additional differentially enriched proteins with actions on the heart and kidney, but the biological signatures remained the same. The replication of mechanistic signatures across discovery and validation cohorts closely aligns with the experimental effects of SGLT2 inhibitors. Thus, the actions of SGLT2 inhibitors—to promote autophagy, restore mitochondrial health and production of ATP, promote iron mobilization and erythropoiesis, influence renal tubular ion reabsorption, and normalize cardiac and renal structure and function—are likely to be relevant to patients with heart failure. (EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction [EMPEROR-Preserved], NCT03057951 ; EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Reduced Ejection Fraction [EMPEROR-Reduced], NCT03057977) [ABSTRACT FROM AUTHOR]

Purpose: Breast cancer is a common malignancy in women, and its metastasis is a leading cause of cancer-related deaths. Single-cell RNA sequencing (scRNA-seq) can distinguish the molecular characteristics of metastasis and identify predictor genes for patient prognosis. This article explores gene expression in primary breast cancer tumor tissue against metastatic cells in the lymph node and liver using scRNA-seq. Methods: Breast cancer scRNA-seq data from the Gene Expression Omnibus were used. The data were processed using R and the Seurat package. The cells were clustered and identified using Metascape. InferCNV is used to analyze the variation in copy number. Differential expression analysis was conducted for the cancer cells using Seurat and was enriched using Metascape. Results: We identified 18 distinct cell clusters, 6 of which were epithelial. CNV analysis identified significant alterations with duplication of chromosomes 1, 8, and 19. Differential gene analysis resulted in 17 upregulated and 171 downregulated genes for the primary tumor in the primary tumor vs. liver metastasis comparison and 43 upregulated and 4 downregulated genes in the primary tumor in the primary tumor vs lymph node metastasis comparison. Several enriched terms include Ribosome biogenesis, NTP synthesis, Epithelial dedifferentiation, Autophagy, and genes associated with epithelial-to-mesenchymal transitions. Conclusion: No single gene or pathway can clearly explain the mechanisms behind tumor metastasis. Several mechanisms contribute to lymph node and liver metastasis, such as the loss of differentiation, epithelial-to-mesenchymal transition, and autophagy. These findings necessitate further study of metastatic tissue for effective drug development. [ABSTRACT FROM AUTHOR]

Summary Autophagy is a conserved degradation pathway that regulates the clearance of paternal substrate at the early embryogenesis stage of animals. However, its mode of action is likely different in plants, which can regenerate through apomixis without fertilisation. Somatic embryogenesis (SE) is a unique plant process widely used for plant propagation and germplasm utilisation. Here, we studied citrus as an example and found a higher autophagic activity after SE initiation. Interestingly, amyloplasts were frequently found inside autophagosomes, whereas the inhibition of autophagy blocks amyloplasts/starch degradation and hinders somatic embryo formation. Furthermore, the consumption of storage lipids was faster in autophagy mutants, suggesting lipid metabolism is activated when starch utilisation is blocked. Exogenous application of autophagy‐inducing chemicals (e.g. spermidine) significantly promoted the formation of autophagosomes and increased SE efficiency, indicating a positive correlation between autophagy, energy metabolism, and somatic embryo formation in citrus. Taken together, our study unveils a pathway for the degradation of plant‐specific organelles and provides an effective approach for plant propagation. [ABSTRACT FROM AUTHOR]

Background and Purpose : Cancer remains one of the leading causes of death globally. In pursuit of alternative treatments, nature-based ones are especially in demand due to the perceived lesser toxicity and cost-effectiveness. Plumbagin, a naphthoquinone compound derived from the Plumbaginaceae family, has demonstrated significant anticancer properties. It is a yellow crystalline phytochemical that exhibits potent cytotoxic effects against various cancer cells in vitro and in vivo. Results : Its distinct anticancer mechanisms include modulating signaling pathways, such as NF-kβ, STAT3, MMP-9, VEGF, and Akt, induction of apoptosis, autophagy, cell cycle regulation etc. Furthermore, plumbagin also induces reactive oxygen species (ROS) generation and causes oxidative DNA damage. An exciting feature of plumbagin is its ability to sensitize chemo and radio resistant cancer cells. Even with significant anticancer potential, plumbagin is yet to be used in clinics due to its high lipophilicity, insolubility in water, short half-life, and low melting point. To conquer these limitations and possible exploitation of this potent natural compound, the scientific community has used several nano-based delivery systems, such as liposomes, niosomes, micelles, microparticles etc. Conclusion : Despite all these promising attributes, rigorous preclinical and clinical evaluations are essential to validate its actual anticancer potential before considering it as one of the mainstream phytotherapeutic agents. [Display omitted] • The current article is a comprehensive summary of anticancer potential of plumbagin in different cancer models. • The mechanism of action of plumbagin affecting different signaling cascade has been highlighted. • Despite their significant therapeutic potential, plumbagin is yet to be exploited in clinics. The reason and troubleshoot have been suggested. • Various nanoformulations of plumbagin have been covered that showed better efficacy compared to free plumbagin. [ABSTRACT FROM AUTHOR]

Vici syndrome (VICIS) is a congenital disorder characterized by agenesis of the corpus callosum, cataracts, hypopigmentation, cardiomyopathy, combined immunodeficiency, microcephaly, and failure to thrive. This study aimed to elucidate the number of patients with VICIS, its clinical characteristics and relevant genetic information in Japan. After developing diagnostic criteria for VICIS, we conducted a nationwide questionnaire-based survey of VICIS in Japan. In the initial survey, we investigated the number of VICIS patients who fulfilled definite or probable criteria. The second survey was used to obtain detailed clinical and genetic information of VICIS from institutions that responded to the initial survey. Clinical information was available for 15 patients (12 definite, three probable). As of October 2023, nine patients (60%) were alive and six (40%) had died. All patients presented with developmental delay, agenesis of the corpus callosum, elevated serum aspartate/alanine aminotransferase, hypopigmentation and hypotonia. Developmental delay was profound. Most patients developed recurrent infection, high-arched palate, epilepsy, failure to thrive, and microcephaly. Cardiomyopathy and cataracts, both initially described as principal features in VICIS, were notably uncommon in our study. Based on the information collected, all 14 patients for whom information was available received home medical care: 11 (79%) received tube feeding, three (21%) required noninvasive ventilation, four (29%) required tracheostomy, and four (29%) required home subcutaneous immunoglobulin administration. This study revealed for the first time the nationwide status of patients with VICIS in Japan. The mortality rate of patients with VICIS is as high as 40%, and almost all VICIS patients require various forms of home medical care, necessitating comprehensive management. Additionally, we identified one adult patient, underscoring the need for comprehensive medical management extending into adulthood for patients with VICIS. [ABSTRACT FROM AUTHOR]

Porphyromonas gingivalis (P. gingivalis), the main pathogen responsible for periodontitis, is linked to systemic disorders via the oral-gut axis. Short-chain fatty acids (SCFAs) are vital for gut health, but their role in P. gingivalis-induced gut disorders remains unclear. This study utilized metabolomics and 16 S rRNA sequencing to explore gut microbiota and SCFAs levels in P. gingivalis-induced periodontitis mouse models. Significant changes were observed in gut, including a reduction in SCFAs-producing bacteria, such as Lactobacillus, Ligilactobacillus, Allobucalum, and a notable decrease in Firmicutes and Actinobacteriota. The intestinal permeability tests and histological analyses revealed that periodontitis led to epithelial inflammation, reduced mucin secretion, and compromised gut barrier integrity. In vitro experiments with Caco-2 cells co-cultured with P. gingivalis showed that the bacterium disrupted cellular junctions by impairing autophagy, specifically through the ATG5-LC3 pathway, leading to decreased expression of tight junction proteins and reduced SCFA absorption. Remarkably, rapamycin treatment both in vitro and in vivo restored gut barrier function by enhancing autophagy, increasing tight junction protein expression, and promoting SCFAs absorption via MCT1 and SMCT1, alongside GPR43/GPR109a pathway activation. These findings reveal autophagy's novel role in regulating SCFAs metabolism in P. gingivalis-induced gut dysbiosis, offering insights for preventing and treating periodontitis-related systemic diseases. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) has been identified as a significant contributing factor to the exacerbation of chronic obstructive pulmonary disease (COPD). It has been observed that PM 2.5 may induce lung fibrosis in COPD, although the precise molecular mechanism behind this remains unclear. In a previous study, we demonstrated that PM 2.5 upregulates oxidative stress induced growth inhibitor 1 (OSGIN1), which in turn leads to injury in airway epithelial cells, thereby, suggesting a potential link between PM 2.5 exposure and COPD. Based on this, we hypothesized that OSGIN1 plays a role in PM 2.5 -induced fibrosis in COPD. Human bronchial epithelial cells (HBEs) were treated with cigarette smoke extract (CSE) to construct an in vitro model of COPD. Our findings revealed that PM 2.5 increased fibrosis indicators and upregulated OSGIN1 in CSE-stimulated HBEs (CSE-HBEs), and knockdown of OSGIN1 reduced the expression of fibrosis indicators. Through the use of microRNA target prediction software and the Gene Expression Omnibus database, we predicted miRNAs that targeted OSGIN1 in COPD. Subsequently, real-time polymerase chain reaction and western blot analysis confirmed that PM 2.5 modulated miR-654–5p to regulate OSGIN1 in CSE-HBEs. Western blot demonstrated that OSGIN1 induced autophagy, thereby exacerbating fibrosis in CSE-HBEs. In summary, our results suggest that PM 2.5 upregulates OSGIN1 through inhibiting miR-654–5p, leading to increased autophagy and fibrosis in CSE-HBEs. • PM 2.5 promotes fibrosis in CSE-HBEs. • PM 2.5 regulates OSGIN1 to modulate fibrosis in CSE-HBEs. • miR-654–5p negatively regulates OSGIN1 in PM 2.5 -treated CSE-HBEs. • OSGIN1 modulates autophagy in PM 2.5 -treated CSE-HBEs. [ABSTRACT FROM AUTHOR]

Purpose: Bladder cancer is a common genitourinary malignant disease worldwide. Dasatinib is a small molecule inhibitor of Src family kinases. We investigated the anticancer effect and putative molecular mechanisms of dasatinib on T24 and cisplatin-resistant T24R2 human bladder cancer cells. Materials and Methods: Cell proliferation was measured using Cell Counting Kit-8 (CCK-8) and colony formation in dasatinib treated bladder cancer cells. Flow cytometry was used to determined cell cycle arrest and apoptosis. The expression of apoptosis and autophagy related proteins were detected by western blot analysis. Results: In bladder cancer cells, dasatinib significantly reduced cell proliferation, colony formation, and induced G1-phase arrest. Dasatinib triggered apoptosis along with an increased expression of apoptosis-related genes (caspases, PARP, and cytochrome c). Down-regulation of Bcl-2 and up-regulation of Bad, which are hallmarks of apoptosis, were found to play a dominant role in mediating the effects of dasatinib treatment. We further showed that dasatinib inhibits p-Src, p-PI3K, p-Akt, and p-mTOR in bladder cancer cells. Dasatinib also increased the expression of markers of autophagy flux such as LC3-II and p62. Conclusions: These results confirmed that dasatinib is a potent chemotherapeutic drug which induces apoptosis and autophagy by suppressing the PI3K/Akt/mTOR pathway in bladder cancer cells. [ABSTRACT FROM AUTHOR]

Objective(s): This study investigated the inhibitory effect of apatinib on lung cancer cells with high expression of vascular endothelial growth factor-2 (VEGFR-2) and on inducing cellular autophagy and drug resistance. Materials and Methods: The expression of VEGFR-2 was detected using western blotting and RT-PCR. Cell proliferation was measured using the CCK8 and colony formation assays. The cell apoptosis rate was determined using flow cytometry and tunnel assay. Cellular autophagy was detected by measuring the expression of LC3-II using Western blotting and cellular immunofluorescence. The inhibitory effect of apatinib on lung cancer cells and transplanted tumors was observed after treatment with the autophagy inhibitor chloroquine. Results: Apatinib dose-dependently inhibited the proliferation of H1975 and H446 cells; it induced apoptosis via the PARP and caspase-3 pathways in H1975 and H446 cells and effectively inhibited the growth of transplanted tumors. Apatinib induced autophagy in a dose-dependent manner in H1975 and H446 cells. The inhibitory effect of apatinib on cells and the promotion of apoptosis were significantly enhanced after treatment with chloroquine. Immunohistochemistry showed that combining apatinib with chloroquine could reduce the expression of CD31 and Ki67 and increase the expression of caspase-3. Conclusion: Apatinib inhibits proliferation and induces apoptosis in H1975 and H1446 lung cancer cells with high VEGFR2 expression and autophagy in H1975 and H446 cells. [ABSTRACT FROM AUTHOR]

Autophagy regulates the formation of primary cilia, which in turn affects autophagy. The relationship between autophagy and cilia is known to be bidirectional although the specific mechanisms involved have yet to be elucidated. In this study, we found for the first time that ATG8 protein localizes in the basal body of the dorsal kineties and the base of the ventral cirri in Euplotes amieti. ATG8 protein maintains the structural integrity of cilia and plays a role in the construction of the cortical ciliature and microtubule cytoskeleton associated with cilia. ATG8 gene interference leads to the degradation of IFT88, the transport protein in cilia, thus inhibiting the generation of cilia, and affecting the swing of cilia. This influences the swimming speed and cilia pattern, leading to death in Euplotes amieti. [ABSTRACT FROM AUTHOR]

Marine algae, a rich source of bioactive substances, have long been utilized in biomedical and veterinary sciences. This study breaks new ground by assessing the antiviral therapeutic potential of water extracts from four algal species – Colaconema formosanum, Caulerpa microphysa, Gelidium amansii and Sarcodia suae – against vesicular stomatitis virus (VSV) infection. The standout among these was Sarcodia suae water extract (SSWE), which not only significantly repressed VSV replication and enhanced cell survival without cytotoxic effects, but also demonstrated its antiviral activity through interference with viral attachment, entry, RNA replication, and egress, and reduced VSV-induced autophagy in Mv1Lu cells during the late stages of infection. The EC50 of SSWE was 0.422 ± 0.14 mg ml‒1. The cytotoxicity assay confirmed the high biocompatibility of SSWE. This study identifies SSWE as a promising natural antiviral agent and elucidates its mechanisms of action, highlighting the need for further research to optimize its use in controlling VSV-related diseases. Highlights: The bioactive water extract of Sarcodia suae was identified as a sustainable antiviral agent for the algal cultivation industry. The antiviral activity of S. suae against vesicular stomatitis virus (VSV) infection was confirmed. The mechanisms of action of the extract from Sarcodia suae on the autophagic pathway were demonstrated. [ABSTRACT FROM AUTHOR]

Morphine tolerance (MT) is currently a challenging issue related to intractable pain treatment. Studies have shown that reactive oxygen species (ROSs) derived from NADPH oxidase (NOX) and produced in response to endoplasmic reticulum (ER) stress participate in MT development. However, which NOX subtype initiates ER stress during MT development is unclear. NOX4 is mainly expressed on intracellular membranes, such as the ER and mitochondrial membranes, and its sole function is to produce ROS. Whether NOX4 is activated during MT development and the mechanisms underlying the association between NOX4 and ER stress during this process still need to be confirmed. In our study, we used the classic morphine‐tolerant rat model and evaluated the analgesic effect of intrathecally injected morphine through a hot water tail‐flick assay. Our research demonstrated for the first time that chronic morphine administration upregulates NOX4 expression in the spinal cord by activating three ER stress sensors, protein kinase RNA‐like ER kinase (PERK), inositol‐requiring enzyme 1 (IRE1) and activating transcription factor 6 (ATF6), subsequently leading to the activation of microtubule‐associated protein 1 light chain 3 b (LC3B) and P62 (a well‐known autophagy marker) in GABAergic neurons. Our results may suggest that regulating NOX4 and the key mechanism underlying ER stress or autophagy may be a promising strategy to treat and prevent MT development. [ABSTRACT FROM AUTHOR]

Scutellarin, one of natural flavonoids from Scutellaria barbata D. Don and Erigeron breviscapus (vant) Hand.-Mazz. Modern pharmacological studies have shown that scutellarin has a good anti-tumor effect. According to the literature review at home and abroad, scutellarin can inhibit the growth and metastasis of tumor cells, block the cell cycle at various stages, induce apoptosis and autophagy, interfere with tumor metabolism, reverse drug resistance of tumor cells and enhance the sensitivity of chemotherapy drugs. In this paper, the anti-tumor mechanism of scutellarin was reviewed, and the shortcomings of current studies and future research directions were analyzed, so as to provide a basis for further exploration of the anti-tumor potential of scutellarin and its further development and utilization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Selective autophagy is characterized by its ability to specifically degrade a certain substrate, rather than causing widespread cell autophagy. • The mechanisms underlying selective autophagy can be broadly dispersed in three steps: designation, targeting and sequestration, and degradation. • Numerous human diseases and their progression are closely linked to aberrant selective autophagy. • Deciphering the molecular mechanisms underlying selective autophagy provides a theoretical framework for treating relevant clinical disorders. • Regulation of selective autophagy by discovering and developing small-molecule agents has great clinical application prospects for the treatment of related diseases. Autophagy is an evolutionarily conserved turnover process for intracellular substances in eukaryotes, relying on lysosomal (in animals) or vacuolar (in yeast and plants) mechanisms. In the past two decades, emerging evidence suggests that, under specific conditions, autophagy can target particular macromolecules or organelles for degradation, a process termed selective autophagy. Recently, accumulating studies have demonstrated that the abnormality of selective autophagy is closely associated with the occurrence and progression of many human diseases, including neurodegenerative diseases, cancers, metabolic diseases, and cardiovascular diseases. This review aims at systematically and comprehensively introducing selective autophagy and its role in various diseases, while unravelling the molecular mechanisms of selective autophagy. By providing a theoretical basis for the development of related small-molecule drugs as well as treating related human diseases, this review seeks to contribute to the understanding of selective autophagy and its therapeutic potential. In this review, we systematically introduce and dissect the major categories of selective autophagy that have been discovered. We also focus on recent advances in understanding the molecular mechanisms underlying both classical and non-classical selective autophagy. Moreover, the current situation of small-molecule drugs targeting different types of selective autophagy is further summarized, providing valuable insights into the discovery of more candidate small-molecule drugs targeting selective autophagy in the future. On the other hand, we also reveal clinically relevant implementations that are potentially related to selective autophagy, such as predictive approaches and treatments tailored to individual patients. [ABSTRACT FROM AUTHOR]

Summary: The retromer complex is a conserved sorting machinery that maintains cellular protein homeostasis by transporting vesicles containing cargo proteins to defined destinations. It is known to sort proteins at the vacuole membranes for retrograde trafficking, preventing their degradation in the vacuole. However, the detailed mechanism of retromer recruitment to the vacuole membrane has not yet been elucidated.Here, we show that the vacuolar SNARE complex MoPep12‐MoVti1‐MoVam7‐MoYkt6 regulates retromer‐mediated vesicle trafficking by recruiting the retromer to the vacuole membrane, which promotes host invasion in Magnaporthe oryzae.Such recruitment is also essential for the retrieval of the autophagy regulator MoAtg8 and enables appressorium‐mediated host penetration. Furthermore, the vacuolar SNARE subunits are involved in suppressing the host defense response by regulating the deployment of retromer‐MoSnc1‐mediated effector secretion.Altogether, our results provide insights into the mechanism of vacuolar SNAREs‐dependent retromer recruitment which is necessary for pathogenicity‐related membrane trafficking events in the rice blast fungus. [ABSTRACT FROM AUTHOR]

Background and Purpose: Colorectal cancer (CRC) ranks second in mortality worldwide and requires effective and affordable remedies. Cyclovirobuxine D (CVB‐D) is the main effective component of Huangyangning tablet, an approved traditional patent medicine, which is mainly used for cardiovascular treatment. As a multibioactive natural compound, CVB‐D possesses underlying anticancer activities. Experimental Approach: Cell viability and clone‐forming ability were determined in human CRC lines. Western blot, immunofluorescence assay, transmission electron microscopy and senescence‐associated β‐galactosidase (SA‐β‐Gal) staining were utilized to investigate cell autophagy and senescence. The molecular mechanisms were explored by virtual prediction and experimental validation. Patient‐derived xenograft (PDX), dextran sulfate sodium salt (DSS), and azomethane (AOM)/DSS mouse models were employed for in vivo studies. Key Results: CVB‐D inhibited the growth and development of advanced CRC cells / mice by inducing autophagic and senescent activities through the chaperonin containing TCP1 subunit 3 (CCT3)/yes‐associated protein (YAP) axis. CVB‐D acted as a promising inhibitor of CCT3 by interacting with its ATP site. In PDX tumours, CVB‐D showed potential therapeutic effects by targeting CCT3. Treatment with CVB‐D alleviated the mouse model of colitis induced by DSS and attenuated AOM/DSS‐induced formation of adenomatous polyps by its action on CCT3. Conclusions and Implications: Our study has provided a scientific basis for the suggestion that CVB‐D may be recognized as a prospective drug candidate for the therapy of CRC in patients. [ABSTRACT FROM AUTHOR]

Background and Purpose: Doxorubicin is widely used in the treatment of malignant tumours, but doxorubicin‐induced cardiotoxicity severely limits its clinical application. Spexin is a neuropeptide that acts as a novel biomarker in cardiovascular disease. However, the effects of spexin on doxorubicin‐induced cardiotoxicity is unclear. Experimental Approach: We established a model of doxorubicin‐induced cardiotoxicity both in vivo and in vitro. Levels of cardiac damage in mice was assessed through cardiac function assessment, determination of serum cardiac troponin T and CKMB levels and histological examination. CCK8 and PI staining were used to assess the doxorubicin‐induced toxicity in cultures of cardiomyocytes in vitro. Ferroptosis was assessed using FerroOrange staining, determination of MDA and 4‐HNE content and ferroptosis‐associated proteins SLC7A11 and GPX4. Mitochondrial membrane potential and lipid peroxidation levels were measured using TMRE and C11‐BODIPY 581/591 probes, respectively. Myocardial autophagy was assessed by expression of P62 and Beclin1. Key Results: Spexin treatment improved heart function of mice with doxorubicin‐induced cardiotoxicity, and attenuated doxorubicin‐induced cardiotoxicity by decreasing iron accumulation, abnormal lipid metabolism and inhibiting ferroptosis. Interestingly, doxorubicin caused excessive autophagy in cardiomyocyte in culture, which could be alleviated by treatment with spexin. Knockdown of Beclin 1 eliminated the protective effects of spexin in mice with DIC. Conclusion and Implications: Spexin ameliorated doxorubicin‐induced cardiotoxicity by inhibiting excessive autophagy‐induced ferroptosis, suggesting that spexin could be a drug candidate against doxorubicin‐induced cardiotoxicity. Beclin 1 might be critical in mediating the protective effect of spexin against doxorubicin‐induced cardiotoxicity. [ABSTRACT FROM AUTHOR]

Visible light serves as a crucial medium for vision formation.;however, prolonged or excessive exposure to light is recognized as a significant etiological factor contributing to retinal degenerative diseases. The retina, with its unique structure and adaptability, relies on the homeostasis of cellular functions to maintain visual health. Under normal conditions, the retina can mount adaptive responses to various insults, including light-induced damage. Unfortunately, exposure to intense and excessive light triggers a cascade of pathological alterations in retinal photoreceptor cells, pigment epithelial cells, ganglion cells, and glial cells. These alterations encompass disruption of intracellular REDOX and Ca²⁺ homeostasis, pyroptosis, endoplasmic reticulum stress, autophagy, and the release of inflammatory cytokines, culminating in irreversible retinal damage. We first delineate the mechanisms of retinal light damage through 4 main avenues: mitochondria function, endoplasmic reticulum stress, cell autophagy, and inflammation. Subsequently, we discuss protective strategies against retinal light damage, aiming to guide research toward the prevention and treatment of light-induced retinal conditions. • Light damage is considered to be an important pathogenic factor leading to retinal degenerative diseases. • The mechanisms of retinal light damage include the disruption of REDOX balance and Ca2+ homeostasis, pyroptosis, endoplasmic reticulum stress, cell autophagy and inflammatory factor release. • The strategy of retinal light damage protection is promising. [ABSTRACT FROM AUTHOR]

The degenerative process of follicular atresia in hens naturally commences in granulosa cells, significantly impacting laying hens' reproductive performance. Past studies suggested that granulosa cell autophagy and apoptosis work together to cause follicular atresia. Recent research indicates that miRNA regulates granulosa autophagy and apoptosis, which contributes to the development of follicular atresia. However, the role of miR-302c-3p in follicular atresia and development remains unclear. In this study with the RNA-seq approach, we found that miR-302c-3p expression was significantly decreased in atrophic follicles, suggesting its involvement in the follicular atresia process. Following this, we performed in vitro studies to confirm that miR-302c-3p inhibits autophagy and apoptosis in chicken granulosa cells. Mechanistically, LATS2 is considered as the putative target gene of miR-302c-3p, and it has been demonstrated that LATS2 exerts a positive regulatory role in the modulation of autophagy and apoptosis in chicken granulosa cells. Furthermore, we verified the regulatory function of miR-302c-3p in chicken granulosa cells via the LATS2-YAP signaling pathway. Our results collectively demonstrates that miR-302c-3p targets LATS2 to modulate the YAP signaling pathway, impacting autophagy and apoptosis in granulosa cells leading to follicular atresia. [ABSTRACT FROM AUTHOR]

Epigenetic modifications to DNA and chromatin control oncogenic and tumor-suppressive mechanisms in melanoma. Ezh2, the catalytic component of the Polycomb Repressive Complex 2 (PRC2), which mediates methylation of lysine 27 on histone 3 (H3K27me3), can regulate both melanoma initiation and progression. We previously found that mutant Ezh2Y641F interacts with the immune regulator Stat3 and together they affect anti-tumor immunity. However, given the numerous downstream targets and pathways affected by Ezh2, many mechanisms that determine its oncogenic activity remain largely unexplored. Using genetically engineered mouse models, we further investigated the role of pathways downstream of Ezh2 in melanoma carcinogenesis and identified significant enrichment in several autophagy signatures, along with increased expression of autophagy regulators, such as Atg7. In this study, we investigated the effect of Atg7 on melanoma growth and tumor immunity within the context of a wild-type or Ezh2Y641F epigenetic state. We found that the Atg7 locus is controlled by multiple Ezh2 and Stat3 binding sites, Atg7 expression is dependent on Stat3 expression, and that deletion of Atg7 slows down melanoma cell growth in vivo, but not in vitro. Atg7 deletion also results in increased CD8 + T cells in Ezh2Y641F melanomas and reduced myelosuppressive cell infiltration in the tumor microenvironment, particularly in Ezh2WT melanomas, suggesting a strong immune system contribution in the role of Atg7 in melanoma progression. These findings highlight the complex interplay between genetic mutations, epigenetic regulators, and autophagy in shaping tumor immunity in melanoma. [ABSTRACT FROM AUTHOR]

Glioma is the most prevailing main malignant neoplasm of the central nervous system with a miserable prognosis. Temozolomide is the first-line chemotherapy drug for glioma, but its drug resistance reduces temozolomide's clinical efficacy and becomes the principal cause of the failure of glioma chemotherapy. Polyphyllin I (PPI), an active component in Rhizoma Paridis, demonstrates favorable therapeutic actions in diverse malignant neoplasms. Its effect on temozolomide-resistant glioma, however, has not yet been characterized. Here, we demonstrated that polyphyllin I inhibited the proliferation of temozolomide-resistant glioma cell in a concentration-dependent manner. Further, we found that polyphyllin I had a direct effect on temozolomide-resistant glioma tumor cells and promote reactive oxygen species (ROS)-dependent apoptosis and autophagy via mitogen-activated protein kinase (MAPK)-signaling (p38-JNK) pathway. Mechanistically, we showed that polyphyllin I downregulate the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway, indicating that polyphyllin I may be an expected therapeutic strategy for patients with temozolomide-resistant gliomas. [ABSTRACT FROM AUTHOR]

Periodontitis is a chronic inflammatory oral disease that impaired the tooth-supporting apparatus, including gingival tissue destruction and alveolar bone resorption. The initiation of periodontitis is linked to the presence of oral bacteria, particularly P. gingivalis within pathogenic biofilms. Here, we demonstrated the central role of the autophagy regulator Transcription Factor EB (TFEB) in orchestrating autophagy activation and modulating the host immune response against P. gingivalis in periodontitis. Upregulation of TFEB expression at the protein level and heightened nuclear localization occurred during the progressive stages of periodontitis. Functionally, TFEB overexpression emerges as a potent alleviator of periodontitis-associated phenotypes, operating through the activation of autophagy and the inhibition of the NF-κB pathway in both in vivo and in vitro models. In addition, TFEB knockdown exacerbates the inflammatory response by upregulating pro-inflammatory cytokines. The dual regulatory role of TFEB in governing both autophagy and inflammatory responses unveils novel insights into periodontitis pathogenesis, positioning TFEB as a promising therapeutic target for periodontitis intervention. [ABSTRACT FROM AUTHOR]

Apolipoprotein E is the major lipid transporter in the brain and an important player in neuron-astrocyte metabolic coupling. It ensures the survival of neurons under stressful conditions and hyperactivity by nourishing and detoxifying them. Apolipoprotein E polymorphism, combined with environmental stresses and/or age-related alterations, influences the risk of developing late-onset Alzheimer's disease. In this review, we discuss our current knowledge of how apolipoprotein E homeostasis, i.e. its synthesis, secretion, degradation, and lipidation, is affected in Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Intra-neuronal accumulation of hyper-phosphorylated tau as neurofibrillary tangles (NFT) is a hallmark of Alzheimer's disease (AD). To prevent the aggregation of phosphorylated tau in neurons, decreasing the phosphorylated tau protein levels is important. Here, we examined the biological effects of rottlerin, a phytochemical compound extracted from the Kamala tree, Mallotus philippinensis, on phosphorylated tau levels. Notably, rottlerin decreased the levels of intracellular phosphorylated and total tau. A marked increase in the LC3-II, a hallmark of autophagy, was observed in these cells, indicating that rottlerin strongly induced autophagy. Interestingly, rottlerin induced the phosphorylation of Raptor at S792 through the activation of adenosine-monophosphate activated-protein kinase (AMPK), which likely inhibits the mammalian target of rapamycin complex 1 (mTORC1), thus resulting in the activation of transcription factor EB (TFEB), a master regulator of autophagy. In addition, nuclear factor erythroid 2-related factor 2 (Nrf2) activity increased in the presence of rottlerin. The decrease of phosphorylated tau levels in the presence of rottlerin was ameliorated by the knockdown of TFEB and partially attenuated by the knockout of the Nrf2 gene. Taken together, rottlerin likely enhances the degradation of phosphorylated tau through autophagy activated by TFEB and Nrf2. Thus, our results suggest that a natural compound rottlerin could be used as a preventive and therapeutic drug for AD. [ABSTRACT FROM AUTHOR]

Epilepsy is a chronic neurological disorder characterized by recurrent seizures. Despite various treatment approaches, a significant number of patients continue to experience uncontrolled seizures, leading to refractory epilepsy. The emergence of novel anti-epileptic drugs, such as perampanel (PER), has provided promising options for effective epilepsy treatment. However, the specific mechanisms underlying the therapeutic effects of PER remain unclear. This study aimed to investigate the intrinsic molecular regulatory mechanisms involved in the downregulation of GluA2, a key subunit of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, following epileptic seizures. Primary mouse hippocampal neurons were cultured and subjected to an epilepsy cell model. The expression levels of GluA2 and autophagy-related proteins were assessed using Western blotting and real-time fluorescent quantitative PCR. Immunofluorescence and immunohistochemistry techniques were employed to investigate the nuclear translocation of CREB-regulated transcriptional coactivator 1 (CRTC1). Additionally, status epilepticus animal models were established to further validate the findings. The epilepsy cell model exhibited a significant decrease in GluA2 expression, accompanied by elevated levels of autophagy-related proteins. Immunofluorescence analysis revealed the nuclear translocation of CRTC1, which correlated with the expression of autophagy-related genes. Treatment with an autophagy inhibitor reversed the decreased expression of GluA2 in the epilepsy cell model. Furthermore, the calcium/calmodulin-dependent protein phosphatase inhibitor FK506 and CaN overexpression affected the dephosphorylation and nuclear translocation of CRTC1, consequently influencing GluA2 expression. Animal model results further supported the involvement of these molecular mechanisms in epilepsy. Our findings suggest that the downregulation of GluA2 following epileptic seizures involves the activation of autophagy and the regulation of CRTC1 nuclear translocation. These intrinsic molecular regulatory mechanisms provide potential targets for developing novel therapeutic strategies to alleviate refractory epilepsy and preserve cognitive functions in patients. [ABSTRACT FROM AUTHOR]

This study explores the molecular underpinnings of neuropathic pain (NPP) and neuroinflammation, focusing on the role of TRIM28 in the regulation of autophagy and microglia ferroptosis. Leveraging transcriptomic data associated with NPP, we identified TRIM28 as a critical regulator of ferroptosis. Through comprehensive analysis, including Gene Ontology enrichment and protein-protein interaction network assessments, we unveiled GSK3B as a downstream target of TRIM28. Experimental validation confirmed the capacity of TRIM28 to suppress GSK3B expression and attenuate autophagic processes in microglia. We probed the consequences of autophagy and ferroptosis on microglia physiology, iron homeostasis, oxidative stress, and the release of proinflammatory cytokines. In a murine model, we validated the pivotal role of TRIM28 in NPP and neuroinflammation. Our analysis identified 20 ferroptosis regulatory factors associated with NPP, with TRIM28 emerging as a central orchestrator. Experimental evidence affirmed that TRIM28 governs microglial iron homeostasis and cell fate by downregulating GSK3B expression and modulating autophagy. Notably, autophagy was found to influence oxidative stress and proinflammatory cytokine release through the iron metabolism pathway, ultimately fueling neuroinflammation. In vivo experiments provided conclusive evidence of TRIM28-mediated pathways contributing to heightened pain sensitivity in neuroinflammatory states. The effect of TRIM28 on autophagy and microglia ferroptosis drives NPP and neuroinflammation. These findings offer promising avenues for identifying novel therapeutic targets to manage NPP and neuroinflammation. [ABSTRACT FROM AUTHOR]

In sepsis, bacterial components, particularly lipopolysaccharide (LPS), trigger organ injuries such as liver dysfunction. Although sepsis induces hepatocyte damage, the mechanisms underlying sepsis‐related hepatic failure remain unclear. In this study, we demonstrated that the LPS‐treated rat hepatocyte cell line Clone 9 not only induced reactive oxygen species (ROS) generation and apoptosis but also increased the expression of the autophagy marker proteins LC3‐II and p62, and decreased the expression of intact Lamp2A, a lysosomal membrane protein. Additionally, LPS increased lysosomal membrane permeability and galectin‐3 puncta formation, and promoted lysosomal alkalization in Clone 9 cells. Pharmacological inhibition of caspase‐8 and cathepsin D (CTSD) suppressed the activation of caspase‐3 and rescued the viability of LPS‐treated Clone 9 cells. Furthermore, LPS induced CTSD release associated with lysosomal leakage and contributed to caspase‐8 activation. Pretreatment with the antioxidant N‐acetylcysteine (NAC) not only diminished ROS generation and increased the cell survival rate, but also decreased the expression of activated caspase‐8 and caspase‐3 and increased the protein level of Lamp2A in LPS‐treated Clone 9 cells. These results demonstrate that LPS‐induced ROS causes lysosomal membrane permeabilization and lysosomal cell death, which may play a crucial role in hepatic failure in sepsis. Our results may facilitate the development of new strategies for sepsis management. [ABSTRACT FROM AUTHOR]

Food contaminates, such as insecticide, may influence the toxicity of nanoparticles (NPs) to intestine. The present study investigated the combined toxicity of TiO2 NPs and fipronil to male mouse intestine. Juvenile mice (8 weeks) were orally exposed to 5.74 mg/kg TiO2 NPs, 2.5 mg/kg fipronil, or both, once a day, for 5 days. We found that both TiO2 NPs and fipronil induced some pathological changes in intestines, accompanying with defective autophagy, but these effects were not obviously enhanced after TiO2 NP and fipronil co‐exposure. Fipronil promoted Ti accumulation but induced minimal impact on other trace elements in TiO2 NP‐exposed intestines. Metabolomics data revealed that the exposure altered metabolite profiles in mouse intestines, and two KEGG pathways, namely, ascorbate and aldarate metabolism (mmu00053) and glutathione metabolism (mmu00480), were only statistically significantly changed after TiO2 NP and fipronil co‐exposure. Five metabolites, including 2‐deoxy‐D‐erythro‐pentofuranose 5‐phosphate, 5alpha‐cholestanol, beta‐D‐glucopyranuronic acid, elaidic acid, and isopentadecanoic acid, and maltotriose, were more significantly up‐regulated after the co‐exposure, whereas trisaccharide and xylonolactone were only significantly down‐regulated by the co‐exposure. We concluded that fipronil had minimal impact to enhance the toxicity of TiO2 NPs to mouse intestines but altered metabolite profiles. This study investigated the combined toxicity of TiO2 NPs and fipronil to male mouse intestines after repeated oral exposure. We found that TiO2 NPs and fipronil induced pathological changes and defective autophagy, but there were no obvious synergistic effects. Metabolomics data revealed that some KEGG pathways and metabolites were more significantly altered after the co‐exposure compared with single exposure. We concluded that fipronil had minimal impact to enhance the toxicity of TiO2 NPs to mouse intestines but altered metabolite profiles. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the anticancer effects of piceatannol, a natural stilbenoid, on human neuroblastoma cells. In order to accomplish this goal, we performed various cellular assays, including the XTT cell proliferation assay for cell viability, colony formation assay for colony formation capacity, FITC Annexin V and cell death detection kit for apoptosis, matrigel invasion assay for invasion capacity, intracellular reactive oxygen species (ROS) red dye for intracellular ROS levels, TMRM staining method for mitochondrial membrane potential (MMP), and the CYTO‐ID autophagy detection kit for autophagy. Furthermore, we analyzed the expression levels of genes associated with apoptosis and autophagy using RT‐qPCR. Based on our findings, piceatannol exhibited cytotoxic effects on neuroblastoma cells. Besides, treatment with piceatannol at both 50 and 100 μM concentrations for 72 h decreased colony formation, induced apoptosis and autophagy, inhibited cell invasion, decreased MMP, and increased ROS levels in SH‐SY5Y cells. In addition, we observed significant upregulation in the expression levels of CASP8, BECLIN, ATG5, ATG7, and MAPILC3A genes between the two doses. These results suggest that piceatannol enhances autophagic activity and induces caspase‐dependent apoptosis, indicating its potential as a therapeutic agent against neuroblastoma cells. In this study, piceatannol, a natural stilbenoid with anti‐inflammatory and antioxidant properties, suppressed cell proliferation, colony formation capacity and invasion in neuroblastoma cells. It also decreased the mitochondrial membrane potential while increasing the level of reactive oxygen species. In addition, it induced apoptosis and autophagy, and this effect was also observed at the molecular level in the expression levels of genes related to apoptosis and autophagy. [ABSTRACT FROM AUTHOR]

The overactivation of β‐adrenergic receptors (β‐ARs) can result in acute myocardial ischemic injury, culminating in myocardial necrosis. Berberine (BBR) has exhibited promising potential for prevention and treatment in various heart diseases. However, its specific role in mitigating myocardial injury induced by acute β‐AR overactivation remains unexplored. This study aimed to investigate the effects and underlying mechanisms of BBR pretreatment in a rat model of acute β‐AR overactivation induced by a single dose of the nonselective β‐adrenergic agonist isoprenaline (ISO). Rats were pretreated with saline or BBR (100 mg/kg/day) via gavage for 14 consecutive days, followed by a subcutaneous injection of ISO or saline on the 14th day. The findings indicated that BBR pretreatment significantly attenuated myocardial injury in ISO‐stimulated rats, as evidenced by reduced pathological inflammatory infiltration, necrosis, and serum markers of myocardial damage. Additionally, BBR decreased oxidative stress and inflammation in the system and heart. Furthermore, BBR pretreatment enhanced myocardial ATP levels, improved mitochondrial dysfunction through increased Drp1 phosphorylation, and augmented myocardial autophagy. In a CoCl2‐induced H9c2 cell hypoxic injury model, BBR pretreatment mitigated cellular injury, apoptosis, and oxidative stress while upregulating Drp1 and autophagy‐associated proteins. Mechanistically, BBR pretreatment activated AKT, AMPK, and LKB1 both in vivo and in vitro, implicating the involvement of the AKT and LKB1/AMPK signaling pathways in its cardioprotective effects. Our study demonstrated the protective effects of BBR against myocardial injury induced by acute β‐AR overactivation in rats, highlighting the potential of BBR as a preventive agent for myocardial injury associated with β‐adrenergic overactivation. This study aimed to investigate the effects and underlying mechanisms of berberine (BBR) pretreatment in a rat model of acute β‐adrenergic overactivation induced by a single dose of the nonselective β‐adrenergic agonist isoprenaline (ISO), and in a CoCl2‐induced H9c2 cell hypoxic injury model. Our findings suggest that pretreatment with BBR confers protection against myocardial injury by activating AKT, AMPK, and LKB1 signaling pathways both in vivo and in vitro, ameliorating mitochondrial dysfunction and enhancing myocardial autophagy. [ABSTRACT FROM AUTHOR]

Background: Transmembrane 9 superfamily member 1 (TM9SF1) is involved in inflammation. Since both inflammatory and autoimmune diseases are linked to immune cells regulation, this study investigated the association between TM9SF1 expression and autoimmune disease activity. As B cell differentiation and autoantibody production exacerbate autoimmune disease, the signaling pathways involved in these processes were explored. Methods: Tm9sf1−/− mouse rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) models were used to verify the relationship between gene expression and disease severity. Peripheral blood mononuclear cells (PBMCs) from 156 RA and 145 SLE patients were used to explore the relationship between TM9SF1 expression and disease activity. The effectiveness of TM9SF1 as a predictor of disease activity was assessed using multiple logistic regression and receiver operating characteristic (ROC) curves. The signaling pathways regulated by TM9SF1 in B cell maturation and antibody production were conducted by plasma cell induction experiment in vitro. Results: The Tm9sf1−/− RA and SLE model mice produced fewer autoantibodies and showed reduced disease severity relative to wild-type (WT) mice. TM9SF1 levels in PBMCs of patients were higher than those in healthy controls, and were reduced in patients with low disease activity relative to those with active RA and SLE. Furthermore, TM9SF1 levels were positively linked with autoantibody titers and pro-inflammatory cytokine levels in both diseases. ROC analyses indicated TM9SF1 outperformed several important clinical indicators in predicting disease activity (area under the curve (AUC) were 0.858 and 0.876 for RA and SLE, respectively). In vitro experiments demonstrated that Tm9sf1 knockout blocked differentiation of B cells into antibody-producing plasma cells by activating mTOR and inhibiting autophagy, and mTOR inhibitors such as rapamycin could reverse this effect. Conclusions: The primary finding was the identification of the molecular mechanism underlying autophagy regulation in B cells, in which Tm9sf1 knockout was found to modulate mTOR-dependent autophagy to block B cell differentiation into antibody-secreting plasma cells. It was also found that TM9SF1 expression level in PBMCs was an accurate indicator of disease activity in patients with RA and SLE, suggesting its clinical potential for monitoring disease activity in these patients. [ABSTRACT FROM AUTHOR]

Background: Small cell lung cancer (SCLC) stands as one of the most lethal malignancies, characterized by a grim diagnosis and prognosis. The emergence of multi-drug resistance poses a significant hurdle to effective therapy. Although previous studies have implicated the long noncoding RNA LYPLAL1-DT in the tumorigenesis of SCLC, the precise role of the highly expressed LYPLAL1-DT in SCLC chemoresistance and the underlying mechanism remain inadequately understood. Methods: cDDP-, VP-16- and PTX-resistant SCLC cells lines were established. The viabilities of SCLC cells were assessed by CCK-8 assay in vitro and xenograft tumor formation assay in vivo. Apoptosis was evaluated by FACS, Western blot and JC-1 fluorescence staining, while autophagy was explored via autophagic flux detection under confocal microscopy and autophagic vacuole investigation under transmission electron microscopy (TEM). The functional role and mechanism of LYPLAL1-DT were further investigated by gain- and loss-of-function assays in vitro. Furthermore, the therapeutic efficacy of the combination of venetoclax and HCQ with cDDP, VP-16 or PTX was evaluated by cell line, cell-derived xenograft (CDX) and patient-derived xenograft (PDX) mice model. Results: Our findings revealed that LYPLAL1-DT is upregulated in chemoresistant SCLC cell lines. Gain- and loss-of-function assays demonstrated that LYPLAL1-DT impairs sensitivity to cDDP, VP-16, or PTX both in vitro and in vivo. Overexpression of LYPLAL1-DT significantly enhanced autophagy and inhibited apoptosis in SCLC cells. Further analyses, including RIP and RNA pull-down assays, revealed that LYPLAL1-DT promotes the expression of BCL2 by sponging miR-204-5p and is implicated in the assembly of the autophagy-specific complex (BECN1/PtdIns3K complex). Combining venetoclax and HCQ with cDDP, VP-16, or PTX effectively mitigated chemoresistance in SCLC cells and suppressed tumor growth in CDX and PDX models without inducing obvious toxic effects. Conclusions: Our findings demonstrate that upregulation of LYPLAL1-DT sequesters apoptosis through the LYPLAL1-DT/miR-204-5p/BCL2 axis and promotes autophagy by facilitating the assembly of the BECN1/PtdIns3K complex, thereby mediating multi-drug resistance of SCLC. The triple combination of venetoclax, HCQ, in conjunction with cDDP, VP-16 or PTX overcomes refractory SCLC, shedding light on a potential therapeutic target for combating SCLC chemoresistance. [ABSTRACT FROM AUTHOR]

Autophagy is an important lysosomal degradation process that digests and recycles bio-molecules, protein or lipid aggregates, organelles, and invaded pathogens. Autophagy plays crucial roles in regulation of metabolic and oxidative stress and multiple pathological processes. In cancer, the role of autophagy is dual and paradoxical. Ubiquitination has been identified as a key regulator of autophagy that can influence various steps in the autophagic process, with autophagy-related proteins being targeted for ubiquitination, thus impacting cancer progression and the effectiveness of therapeutic interventions. This review will concentrate on mechanisms underlying autophagy, ubiquitination, and their interactions in cancer, as well as explore the use of drugs that target the ubiquitin-proteasome system (UPS) and ubiquitination process in autophagy as part of cancer therapy. [ABSTRACT FROM AUTHOR]

Ischemia reperfusion (I/R) was considered as one of main causes of acute kidney injury (AKI). However, the exact mechanism remains unclear. Here, this study aimed to investigate the role and mechanism of the m6A demethylase fat mass and obesity‐associated (FTO) protein in I/R‐induced AKI. HK‐2 cells and SD rats were utilized to establish hypoxia/reoxygenation (H/R) or I/R induced AKI models. The changes of RNAs and proteins were quantified using RT‐qPCR, western blot, and immunofluorescence assays, respectively. Cell proliferation and apoptosis were assessed by CCK‐8 and flow cytometry. Interactions between molecules were investigated using RIP, ChIP, Co‐IP, RNA pull‐down, and dual luciferase reporter assays. Global m6A quantification was evaluated by kits. TUNEL and HE staining were employed for histopathological examinations. Oxidative stress‐related indicators and renal function were determined using ELISA assays. The FTO expression was downregulated in H/R‐induced HK‐2 cells and renal tissues from I/R‐induced rats. Overexpression of FTO improved the cell viability but repressed apoptosis and oxidative stress in H/R‐treated HK‐2 cells, as well as enhanced renal function and alleviated kidney injury in I/R rats. Notably, the FTO overexpression significantly increased autophagy‐related LC3 and ULK1 levels. When autophagy was inhibited, the protective effects of FTO in AKI were diminished. Notably, Ambra1, a crucial regulator of autophagy, was repressed in H/R‐induced HK‐2 cells. However, the FTO overexpression restored the Ambra1 expression by reducing m6A modification of its mRNA. SP1, acting as an upstream transcription factor, directly interacts with the FTO promoter to enhance FTO expression. Knockdown of SP1 or Ambra1 suppressed the beneficial effects of FTO upregulation on autophagy and oxidative stress injury in H/R‐stimulated cells. FTO, transcriptionally activated by SP1, promoted autophagy by upregulating Ambra1/ULK1 signaling, thereby inhibiting oxidative stress and kidney injury. These findings may provide some novel insights for AKI treatment. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common neurodegenerative disease, and a defect in neuronal plasma membrane repair could exacerbate neurotoxicity, neuronal death, and disease progression. In this study, application of AD patient cerebrospinal fluid (CSF) and recombinant human Aβ to otherwise healthy neurons induces defective neuronal plasma membrane repair in vitro and ex vivo. We identified Aβ as the biochemical component in patient CSF leading to compromised repair capacity and depleting Aβ rescued repair capacity. These elevated Aβ levels reduced expression of dysferlin, a protein that facilitates membrane repair, by altering autophagy and reducing dysferlin trafficking to sites of membrane injury. Overexpression of dysferlin and autophagy inhibition rescued membrane repair. Overall, these findings indicate an AD pathogenic mechanism where Aβ impairs neuronal membrane repair capacity and increases susceptibility to cell death. This suggests that membrane repair could be therapeutically targeted in AD to restore membrane integrity and reduce neurotoxicity and neuronal death. [ABSTRACT FROM AUTHOR]

Objective To explore the role of autophagy in improving fluoride-induced SH-SY5Y cytotoxicity by grape seed proanthocyanidins (GSPE) in human neuroblastoma. Methods SH-SY5Y cells were treated with sodium fluoride (60 mg/L) for 24 h to establish a fluoride-infected cell model, and then were randomly divided into the control group, sodium fluoride-infected group, sodium fluoride+low dose GSPE group. sodium fluoride + middle dose GSPE group and sodium fluoride + high dose GSPE group. The cell viability values of each group were detected by CCK-8 assay. Hoechst33342 staining was used to analyze the apoptosis level of each group. Immunofluorescence method was used to analyze the expression of LC3 in each group. The expressions of cleaved-caspase 3, cleaved-PARP, LC3, and p62 were detected by Western blot. Subsequently. Rapamycin was included in the regrouping and the expressions of cleaved-PARP, LC3, p62 and other proteins in each group were detected, and the changes of apoptosis level in each group were analyzed by Hoechst33342 staining. Results Compared with the control group, the apoptosis level of SH-SY5Y cells in the sodium fluoride group was significantly increased (P<0.05), while the cell viability and autophagy level of SH-SY5Y cells were increased after GSPE intervention (P<0.05). Compared with the sodium fluoride group, Rapamycin intervention could effectively inhibit apoptosis, and the autophagy level was further enhanced in the combination of rapamycin and GSPE together (P<0.05). Conclusion GSPE can inhibit SH-SY5Y cell apoptosis induced by NaF, and this role may be related to the activation of autophagy. [ABSTRACT FROM AUTHOR]