Autophagy and human diseases. Cell Res. 2014;24:69-79. [PMID: 24323045 DOI: 10.1038/cr.2013.161]

Omic AI reveals new autophagy regulators from the Atg1 interactome in Saccharomyces cerevisiae

In Saccharomyces cerevisiae, Atg1 is a core autophagy-related (Atg) protein kinase (PK) in regulating macroautophagy/autophagy, by physically interacting with numerous other proteins, or by phosphorylating various substrates. It is unclear how many Atg1-interacting partners and substrates are also involved in regulating autophagy. Here, we conducted transcriptomic, proteomic and phosphoproteomic profiling of Atg1-dependent molecular landscapes during nitrogen starvation-triggered autophagy, and detected 244, 245 and 217 genes to be affected by ATG1 in the autophagic process at mRNA, protein, and phosphorylation levels, respectively. Based on the Atg1 interactome, we developed a novel artificial intelligence (AI) framework, inference of autophagy regulators from multi-omic data (iAMD), and predicted 12 Atg1-interacting partners and 17 substrates to be potentially functional in autophagy. Further experiments validated that Rgd1 and Whi5 are required for bulk autophagy, as well as physical interactions and co-localizations with Atg1 during autophagy. In particular, we demonstrated that 2 phosphorylation sites (p-sites), pS78 and pS149 of Whi5, are phosphorylated by Atg1 to regulate the formation of Atg1 puncta during autophagy initiation. A working model was illustrated to emphasize the importance of the Atg1-centered network in yeast autophagy. In addition, iAMD was extended to accurately predict Atg proteins and autophagy regulators from other PK interactomes, indicating a high transferability of the method. Taken together, we not only revealed new autophagy regulators from the Atg1 interactome, but also provided a useful resource for further analysis of yeast autophagy.

Kumatakenin alleviates depressive-like behaviors by suppressing excessive autophagy in hippocampus via ATG5

The prevalence of depression has been escalating annually, imposing a substantial burden on both individuals and society. Radix Astragali, a multifaceted herb utilized in traditional Chinese medicine, has been employed in clinical settings for the treatment of depression. Kumatakenin, a principal active constituent of Radix Astragali, has yet to be thoroughly investigated for its potential antidepressant effects. In this study, we elucidated a novel effect of Kumatakenin, which ameliorated depression-like behaviors by modulating excessive autophagy in the hippocampus of mice exhibiting depressive symptoms. Utilizing transmission electron microscopy, we identified a significant increase in autophagosomes within the hippocampal region of depressed mice, which was notably reduced following Kumatakenin administration. Further, molecular docking analyses revealed an interaction between Kumatakenin and autophagy-related gene 5 (ATG5). At the protein level, Kumatakenin administration resulted in a marked decrease in microtubule-associated protein 1 light chain 3 (LC3) and ATG5 levels within hippocampal tissues. At the cellular level, in a corticosterone (CORT)-induced cell model, Kumatakenin significantly diminished the levels of LC3 and ATG5. Upon overexpression of ATG5 through lentiviral transfection, the ability of Kumatakenin to reduce LC3 and ATG5 levels was nullified. These observations suggested that Kumatakenin exerted its antidepressant effects by decreasing LC3 and ATG5 concentrations in hippocampal tissues.

Role of circadian transcription factor REV-ERB in cardiovascular diseases: a review

Circadian rhythm, or the biological clock, is an intrinsic timing system present in organisms that operates on a cycle of approximately 24 h. Nearly every cell in the human body adheres to a specific circadian rhythm, governing various biological processes essential for overall health. REV-ERB, a key circadian clock-regulating gene, plays a crucial role in maintaining the precision of these rhythms. This gene influences many downstream targets associated with diverse pathophysiological processes, including metabolism, autophagy, immunity, inflammation, and aging across multiple organs. REV-ERB specifically impacts cardiac systolic function by regulating myocardial energy metabolism. In contemporary society, health and well-being are increasingly challenged by disruptions to the biological clock, such as night shifts, late-night activities, and jet lag. These disruptions often lead to circadian rhythm disorders, which are now being increasingly linked to heart diseases. This review explored the potential role of REV-ERB in the cardiovascular system. Beyond its role in circadian rhythm regulation, REV-ERB could significantly influence physiological and pathological processes related to cardiovascular health, including atherosclerosis, myocardial ischemia/reperfusion injury, and heart failure. Mechanistically, REV-ERB could regulate glucose and lipid metabolism, inflammation, autophagy, ferroptosis, and mitochondrial function. The review highlighted the protective roles and underlying mechanisms of REV-ERB in cardiovascular diseases, suggesting that multidisciplinary research may provide a basis for breakthroughs in REV-ERB-targeted therapies for cardiovascular disorders.

Autophagy-related protein Atg11 is essential for microtubule-mediated chromosome segregation

Emerging studies hint at the roles of autophagy-related proteins in various cellular processes. To understand if autophagy-related proteins influence genome stability, we sought to examine a cohort of 35 autophagy mutants in Saccharomyces cerevisiae. We observe cells lacking Atg11 show poor mitotic stability of minichromosomes. Single-molecule tracking assays and live cell microscopy reveal that Atg11 molecules dynamically localize to the spindle pole bodies (SPBs) in a microtubule (MT)-dependent manner. Loss of Atg11 leads to a delayed cell cycle progression. Such cells accumulate at metaphase at an elevated temperature that is relieved when the spindle assembly checkpoint (SAC) is inactivated. Indeed, atg11∆ cells have stabilized securin levels, that prevent anaphase onset. Ipl1-mediated activation of SAC also confirms that atg11∆ mutants are defective in chromosome biorientation. Atg11 functions in the Kar9-dependent spindle positioning pathway. Stabilized Clb4 levels in atg11∆ cells suggest that Atg11 maintains Kar9 asymmetry by facilitating proper dynamic instability of astral microtubules (aMTs). Loss of Spc72 asymmetry contributes to non-random SPB inheritance in atg11∆ cells. Overall, this study uncovers an essential non-canonical role of Atg11 in the MT-mediated process of chromosome segregation.

Inhibition of Unc-51-like-kinase is mitoprotective during Pseudomonas aeruginosa infection in corneal epithelial cells

Pseudomonas aeruginosa (PA) is an opportunistic gram-negative pathogen that can infect the cornea, leading to permanent vision loss. Autophagy is a cannibalistic process that drives cytoplasmic components to the lysosome for degradation and/or recycling. Autophagy has been shown to play a key role in the removal of intracellular pathogens and, as such, is an important component of the innate immune response. Autophagy is intimately linked to mitochondria, organelles that mediate energy homeostasis, immune signaling, and cell death. Using a combination of biochemical and imaging approaches, we investigated the effects of PA on autophagy and host cell mitochondria in relation to pro-inflammatory cytokine expression. Using a standard invasive test strain of PA, we show that PA infection triggers dephosphorylation of the mechanistic target of rapamycin in corneal epithelial cells, leading to the induction of autophagy through ULK1/2. This was associated with robust mitochondrial depolarization, changes in mitochondrial ultrastructure, and an increase in IL-6 and IL-8 secretion. PA infection was also associated with an increase in purine metabolism by host cells. Treatment with the ULK1/2 inhibitor, MRT68921, which blocks phagophore formation, attenuated levels of intracellular PA in corneal epithelial cells. Unexpectedly, treatment of cells with MRT68921 blocked PA-induced mitochondrial depolarization and downregulated purine and pyrimidine metabolism. While MRT68921 attenuated the PA-induced increase in IL-6, it further increased IL-8 and neutrophil chemotaxis. This was associated with the nuclear internalization of NFκB. Taken together, these findings highlight a novel mechanism whereby the inhibition of ULK1/2 activity confers mitoprotection during PA infection in corneal epithelial cells.IMPORTANCEPseudomonas aeruginosa (PA) is a common pathogen that can cause severe disease in man. In the eye, PA infection can lead to blindness. In this study, we show that PA induces autophagy, a mechanism whereby cells recycle damaged proteins and organelles. PA infection further depolarizes mitochondria, leading to the release of pro-inflammatory mediators. Unexpectedly, the inhibition of ULK1/2, an enzyme involved in the early stages of autophagy, not only inhibits autophagy but enhances mitochondrial polarization. This leads to a reduction in intracellular levels of PA and changes in the inflammatory milieu. Together, these data suggest that the inhibition of ULK1/2 may be mitoprotective in corneal epithelial cells during PA infection.

Selective clearance of aberrant membrane proteins by TORC1-mediated micro-ER-phagy

Aberrant accumulation and clearance of membrane proteins is associated with disease. Membrane proteins are inserted first to the endoplasmic reticulum (ER). During normal growth, two quality control (QC) processes, ER-associated degradation and macro-ER-phagy, deliver misfolded and excess membrane proteins for degradation in the proteasome and lysosome, respectively. We show that in yeast during normal growth, ER-QC is constitutive, since none of the stress-induced signaling pathways-nutritional, proteotoxic, or heat-are involved. In mutant cells defective in ER-QC, misfolded or excess proteins accumulate and nutritional stress, but not proteotoxic or heat stress, can stimulate their clearance. Early during nutritional stress, clearance occurs in the lysosome through a selective micro-ER-phagy pathway dependent on the ubiquitin ligase Rsp5, its Ssh4 adaptor, and ESCRT. In contrast, only a fraction of normal membrane proteins is degraded much later via macro-autophagy. Because the pathways explored here are conserved, nutritional stress emerges as a possible way for clearing disease-associated membrane proteins.

Sex Disparity in Cancer: Role of Autophagy and Estrogen Receptors

Autophagy, a cellular process essential for maintaining homeostasis, plays a fundamental role in recycling damaged components and in adapting to stress. The dysregulation of autophagy is implicated in numerous human diseases, including cancer, where it exhibits a dual role as both a suppressor and a promoter, depending on the context and the stage of tumor development. The significant sex differences observed in autophagic processes are determined by biological factors, such as genetic makeup and sex hormones. Estrogens, through their interaction with specific receptors, modulate autophagy and influence tumor progression, therapy resistance, and the immune response to tumors. In females, the escape from X inactivation and estrogen signaling may be responsible for the advantages, in terms of lower incidence and longer survival, observed in oncology. Women often show better responses to traditional chemotherapy, while men respond better to immunotherapy. The action of sex hormones on the immune system could contribute to these differences. However, women experience more severe adverse reactions to anticancer drugs. The estrogen/autophagy crosstalk-involved in multiple aspects of the tumor, i.e., development, progression and the response to therapy-deserves an in-depth study, as it could highlight sex-specific mechanisms useful for designing innovative and gender-tailored treatments from the perspective of precision medicine.

Mechanism of mTOR/RILP-regulated autophagic flux in increased susceptibility to myocardial ischemia-reperfusion in diabetic mice

Background

The increased myocardial vulnerability that occurs in diabetic patients following an ischemia-reperfusion injury (I/RI) represents a significant perioperative safety risk. A comprehensive understanding of the intrinsic mechanisms underlying this phenomenon is therefore of paramount importance.

Purposes

The objective of this study is to investigate the potential mechanism of action between impaired autophagic flux and increased vulnerability in diabetic myocardium. This will provide a foundation for the clinical search for effective preventive and curative measures.

Methods

The transcriptomic alterations in autophagy-related genes following myocardial exposure to I/RI were analyzed by single-cell sequencing. This was followed by the validation of potential mechanisms of action between impaired autophagic flux and increased susceptibility at the cellular and animal levels, respectively.

Results

After I/RI in diabetic myocardium, there was a significant increase in the number of CM1 subgroups and a specific downregulation of 239 autophagy-related genes led by RILP. HE staining revealed that myocardial injury was exacerbated in diabetic mice subjected to I/RI. Transmission electron microscopy revealed that the accumulation of autophagic vesicles in cardiomyocytes of diabetic mice resulted in impaired autophagic flux. qRT-PCR revealed that the expression of RILP was significantly reduced in diabetic mice subjected to I/RI. WB showed that P62 was significantly increased and RILP was significantly decreased in diabetic mice subjected to I/RI compared to healthy mice. Inhibition of mTOR during hypoxia/reoxygenation (H/R) injury restored RILP expression and attenuated cellular injury in cardiomyocytes cultured with high glucose.

Conclusion

Following I/RI in diabetic myocardium, an increase in the CM1 subpopulation and a reduction in RILP expression result in impaired autophagic flux. Regulation of the mTOR/RILP pathway can restore impaired autophagic flux and improve myocardial vulnerability, thereby exerting cardioprotective effects.

Insight into interplay between PANoptosis and autophagy: novel therapeutics in ischemic stroke

PANoptosis is a novelly defined mode of programmed cell death that involves the activation of multiple cellular death pathways, including pyroptosis, apoptosis, and necroptosis, triggering robust inflammatory reactions. Autophagy is a crucial cellular process that maintains cellular homeostasis and protects cells from various stresses. PANoptosis and autophagy, both vital players in the intricate pathological progression of ischemic stroke (IS), a brain ailment governed by intricate cell death cascades, have garnered attention in recent years for their potential interplay. While mounting evidence hints at a crosstalk between these two processes in IS, the underlying mechanisms remain elusive. Therefore, this review delves into and dissects the intricate mechanisms that underpin the intersection of PANoptosis and autophagy in this devastating condition. In conclusion, the crosstalk between PANoptosis and autophagy in IS presents a promising target for the development of novel stroke therapies. Understanding the interplay between these two pathways offers a much-needed insight into the underlying mechanisms of IS and opens the possibility for new therapeutic strategies.

A Multi-Omics Analysis of a Mitophagy-Related Signature in Pan-Cancer

Mitophagy, an essential process within cellular autophagy, has a critical role in regulating key cellular functions such as reproduction, metabolism, and apoptosis. Its involvement in tumor development is complex and influenced by the cellular environment. Here, we conduct a comprehensive analysis of a mitophagy-related gene signature, composed of PRKN, PINK1, MAP1LC3A, SRC, BNIP3L, BECN1, and OPTN, across various cancer types, revealing significant differential expression patterns associated with molecular subtypes, stages, and patient outcomes. Pathway analysis revealed a complex interplay between the expression of the signature and potential effects on the activity of various cancer-related pathways in pan-cancer. Immune infiltration analysis linked the mitophagy signature with certain immune cell types, particularly OPTN with immune infiltration in melanoma. Methylation patterns correlated with gene expression and immune infiltration. Mutation analysis also showed frequent alterations in PRKN (34%), OPTN (21%), PINK1 (28%), and SRC (15%), with implications for the tumor microenvironment. We also found various correlations between the expression of the mitophagy-related genes and sensitivity in different drugs, suggesting that targeting this signature could improve therapy efficacy. Overall, our findings underscore the importance of mitophagy in cancer biology and drug resistance, as well as its potential for informing treatment strategies.

Autophagy in cancer development, immune evasion, and drug resistance

Macroautophagy/autophagy is a highly conserved evolutionary mechanism involving lysosomes for the degradation of cytoplasmic components including organelles. The constitutive, basal level of autophagy is fundamental for preserving cellular homeostasis; however, alterations in autophagy can cause disease pathogenesis, including cancer. The role of autophagy in cancer is particularly complicated, since this process acts both as a tumor suppressor in precancerous stages but facilitates tumor progression during carcinogenesis and later stages of cancer progression. This shift between anti-tumor and pro-tumor roles may be influenced by genetic and environmental factors modulating key pathways such as those involving autophagy-related proteins, the PI3K-AKT-MTOR axis, and AMPK, which often show dysregulation in tumors. Autophagy regulates various cellular functions, including metabolism of glucose, glutamine, and lipids, cell proliferation, metastasis, and several types of cell death (apoptosis, ferroptosis, necroptosis and immunogenic cell death). These multifaceted roles demonstrate the potential of autophagy to affect DNA damage repair, cell death pathways, proliferation and survival, which are critical in determining cancer cells' response to chemotherapy. Therefore, targeting autophagy pathways presents a promising strategy to combat chemoresistance, as one of the major reasons for the failure in cancer patient treatment. Furthermore, autophagy modulates immune evasion and the function of immune cells such as T cells and dendritic cells, influencing the tumor microenvironment and cancer's biological behavior. However, the therapeutic targeting of autophagy is complex due to its dual role in promoting survival and inducing cell death in cancer cells, highlighting the need for strategies that consider both the beneficial and detrimental effects of autophagy modulation in cancer therapy. Hence, both inducers and inhibitors of autophagy have been introduced for the treatment of cancer. This review emphasizes the intricate interplay between autophagy, tumor biology, and immune responses, offering insights into potential therapeutic approaches that deploy autophagy in the cancer suppression.

Assessment of Autophagy in Leishmania Parasites

Leishmaniasis is a neglected tropical disease caused by numerous species of Leishmania parasites, including Leishmania major. The parasite is transmitted by several species of sandfly vectors and infects myeloid cells leading to a myriad of inflammatory responses, immune dysregulations, and disease manifestations. Every cell undergoes autophagy, a self-regulated degradative process that permits the cells to recycle damaged or worn-out organelles in order to maintain cellular health and homeostasis. Studies have shown that Leishmania modulates their host cell autophagic machinery and there are indications that the parasite-specific autophagic processes may be valuable for parasite virulence and survival. However, the role of autophagy in Leishmania is inconclusive because of the limited tools available to study the Leishmania-specific autophagic machinery. Here, we describe methods to study and definitively confirm autophagy in Leishmania major. Transmission electron microscopy (TEM) allowed us to visualize Leishmania autophagosomes, especially those containing damaged mitochondrial content, as well as dividing mitochondria with ongoing fusion/fission processes. Flow cytometry enabled us to identify the amount of acridine orange dye accumulating in the acidic vacuolar compartments in Leishmania major by detecting fluorescence in the red laser when autophagic inhibitors or enhancers were included. These methods will advance studies that aim to understand autophagic regulation in Leishmania parasites that could provide insights into developing improved therapeutic targets against leishmaniasis.

Structure of the WIPI3/ATG16L1 Complex Reveals the Molecular Basis for the Recruitment of the ATG12~ATG5-ATG16L1 Complex by WIPI3

Macroautophagy deploys a wealth of autophagy-related proteins to synthesize the double-membrane autophagosome, in order to engulf cytosolic components for lysosome-dependent degradation. The recruitment of the ATG12~ATG5-ATG16L1 complex by WIPI family proteins is a crucial step in autophagosome formation. Nevertheless, the molecular mechanism by which WIPI3 facilitates the recruitment of the ATG12~ATG5-ATG16L1 complex remains largely unknown. Here, we uncover that WIPI3 can directly interact with the coiled-coil domain of ATG16L1. By determining the crystal structure of WIPI3 in complex with ATG16L1 coiled-coil, we elucidate the molecular basis underpinning the specific recruitment of the ATG12~ATG5-ATG16L1 complex by WIPI3. Moreover, we demonstrate that WIPI2 and WIPI3 are competitive for interacting with ATG16L1 coiled-coil, and ATG16L1 and ATG2 are mutually exclusive in binding to WIPI3. In all, our findings provide mechanistic insights into the WIPI3/ATG16L1 interaction, and are valuable for further understanding the activation mechanism of the ATG12~ATG5-ATG16L1 complex as well as the working mode of WIPI3 in autophagy.

Cadmium-Induced Oxidative Damage and the Expression and Function of Mitochondrial Thioredoxin in Phascolosoma esculenta

Phascolosoma esculenta is a unique aquatic invertebrate native to China, whose habitat is highly susceptible to environmental pollution, making it an ideal model for studying aquatic toxicology. Mitochondrial thioredoxin (Trx2), a key component of the Trx system, plays an essential role in scavenging reactive oxygen species (ROS), regulating mitochondrial membrane potential, and preventing ROS-induced oxidative stress and apoptosis. This study investigated the toxicity of cadmium (Cd) on P. esculenta and the role of P. esculenta Trx2 (PeTrx2) in Cd detoxification. The results showed that Cd stress altered the activities of T-SOD and CAT, as well as the contents of GSH and MDA in the intestine. After 96 h of exposure, histological damages such as vacuolization, cell necrosis, and mitophagy were observed. Suggesting that Cd stress caused oxidative damage in P. esculenta. Furthermore, with the prolongation of stress time, the expression level of intestinal PeTrx2 mRNA initially increased and then decreased. The recombinant PeTrx2 (rPeTrx2) protein displayed dose-dependent redox activity and antioxidant capacity and enhanced Cd tolerance of Escherichia coli. After RNA interference (RNAi) with PeTrx2, significant changes in the expression of apoptosis-related genes (Caspase-3, Bax, Bcl-2, and Bcl-XL) were observed. Proving that PeTrx2 rapidly responded to Cd stress and played a vital role in mitigating Cd-induced oxidative stress and apoptosis. Our study demonstrated that PeTrx2 is a key factor for P. esculenta to endure the toxicity of Cd, providing foundational data for further exploration of the molecular mechanisms underlying heavy metal resistance in P. esculenta.

Acetazolamide suppresses the progression of hepatocellular carcinoma induced by diethylnitrosamine in Wistar albino rats

Hepatocellular carcinoma (HCC) continues to be the most prevalent type of liver cancer worldwide. Diethylnitrosamine (DEN)-induced HCC is an extensively used hepatic cancer model in experimental animals. Acetazolamide (AZA) is a carbonic anhydrase enzyme inhibitor. This study aimed to assess the therapeutic mechanism of AZA against DEN-induced HCC. Thirty male Wistar albino rats were divided equally into three groups. Group I (C): control group, Group II (HCC): DEN-induced HCC, and Group III (HCC/AZA): AZA-treated HCC. Verification of the HCC induced by DEN was confirmed by elevated liver enzymes' activities, and increased α-fetoprotein (AFP) levels, as well as distinct liver architecture changes. On the other hand, the AZA-treated HCC group experienced decreases in the activities of serum liver enzymes and AFP levels, as well as, regulated liver architecture. Additionally, it downregulated p-p38 MAPK/p-JNK1/JNK2/p-C-Jun/p-NF-κB p65 protein expressions. Moreover, it ameliorated autophagy by controlling the expression of the p-AMPK/p-mTOR1/LC3 I/II proteins. Furthermore, it downregulated the relative gene expressions of carbonic anhydrase-IX (CAIX) and hexokinase-II (HKII). Histopathological examination of AZA-treated HCC liver tissues supported these findings. Conclusion: AZA provides a new dimension in ameliorating experimentally induced HCC through regulation of hepatic biomarkers, antioxidant status, inflammatory markers, and autophagy, mediated by amelioration of CAIX and HKII gene expressions.

Advances in nanotechnology-assisted photodynamic therapy for neurological disorders: a comprehensive review

Neurological disorders such as neurodegenerative diseases and nervous system tumours affect more than one billion people throughout the globe. The physiological sensitivity of the nervous tissue limits the application of invasive therapies and leads to poor treatment and prognosis. One promising solution that has generated attention is Photodynamic therapy (PDT), which can potentially revolutionise the treatment landscape for neurological disorders. PDT attracted substantial recognition for anticancer efficacy and drug conjugation for targeted drug delivery. This review thoroughly explained the basic principles of PDT, scientific interventions and advances in PDT, and their complicated mechanism in treating brain-related pathologies. Furthermore, the merits and demerits of PDT in the context of neurological disorders offer a well-rounded perspective on its feasibility and challenges. In conclusion, this review encapsulates the significant potential of PDT in transforming the treatment landscape for neurological disorders, emphasising its role as a non-invasive, targeted therapeutic approach with multifaceted applications.

Isobavachin induces autophagy-mediated cytotoxicity in AML12 cells via AMPK and PI3K/Akt/mTOR pathways

Isobavachin (IBA) is a dihydroflavonoid compound with various pharmacological effects. However, further investigation into the hepatotoxicity of IBA is necessary. This study aims to identify the hepatotoxic effects of IBA and explore its potential mechanisms. The study assessed the impact of IBA on the viability of AML12, HepG2, LO2, rat, and mouse primary hepatocytes using MTT and LDH assays. Autophagy was detected in AML12 cells after IBA treatment using electron microscopy, MDC, and Ad-mCherry-GFP-LC3B fluorescence. The effect of IBA on autophagy-related proteins was examined using Western blot. The results showed that IBA had dose-dependent inhibitory effects on five cells, induced autophagy in AML12 cells, and promoted autophagic flux. The study found that IBA treatment inhibited phosphorylation of PI3K, Akt, and mTOR, while increasing phosphorylation levels of AMPK and ULK1. Treatment with both AMPK and PI3K inhibitors reversed the expression of AMPK and PI3K-Akt-mTOR signaling pathway proteins. These results suggest that IBA may have hepatocytotoxic effects but can also prevent IBA hepatotoxicity by inhibiting the AMPK and PI3K/Akt/mTOR signaling pathways. This provides a theoretical basis for preventing and treating IBA hepatotoxicity in clinical settings.

Autophagy Gene BECN1 Intronic Variant rs9890617 Predisposes Individuals to Hepatitis B Virus Infection

Beclin 1 protein encoded by the BECN1 gene plays a critical role in the autophagy pathway which is utilized by the Hepatitis B virus (HBV) for its replication. HBV is known for the subversion of the host's autophagy process for its multiplication. The aim of this study was to determine the role of BECN1 intronic variants in HBV susceptibility. Intronic region variant rs9890617 was analyzed using Human splicing finder v3.1 and was found to alter splicing signals. A total of 712 individuals (494 HBV infected and 218 healthy controls) were recruited in the study and genotyped by applying Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). Statistical analysis revealed that the mutant allele T of rs9890617 was significantly associated with the overall disease risk in the allelic model (OR 1.41; 95%CI 1.00-1.99, p = 0.04). On stratifying the data based on the different stages of HBV infection, the mutant genotype showed a significant association with the chronic group in allelic (OR 1.62; 95%CI 1.11-2.39, p = 0.01), dominant (OR 1.64; 95%CI 1.07-2.52, p = 0.02), and co-dominant (OR 1.55; 95%CI 1.00-2.40, p = 0.04) models. Overall, this is the first study regarding beclin 1 variant rs9890617 and we found a significant association of the mutant T allele with the genetic predisposition to HBV infection.

Autophagy in aging-related diseases and cancer: Principles, regulatory mechanisms and therapeutic potential

Macroautophagy/autophagy is primarily accountable for the degradation of damaged organelles and toxic macromolecules in the cells. Regarding the essential function of autophagy for preserving cellular homeostasis, changes in, or dysfunction of, autophagy flux can lead to disease development. In the current paper, the complicated function of autophagy in aging-associated pathologies and cancer is evaluated, highlighting the underlying molecular mechanisms that can affect longevity and disease pathogenesis. As a natural biological process, a reduction in autophagy is observed with aging, resulting in an accumulation of cell damage and the development of different diseases, including neurological disorders, cardiovascular diseases, and cancer. The MTOR, AMPK, and ATG proteins demonstrate changes during aging, and they are promising therapeutic targets. Insulin/IGF1, TOR, PKA, AKT/PKB, caloric restriction and mitochondrial respiration are vital for lifespan regulation and can modulate or have an interaction with autophagy. The specific types of autophagy, such as mitophagy that degrades mitochondria, can regulate aging by affecting these organelles and eliminating those mitochondria with genomic mutations. Autophagy and its specific types contribute to the regulation of carcinogenesis and they are able to dually enhance or decrease cancer progression. Cancer hallmarks, including proliferation, metastasis, therapy resistance and immune reactions, are tightly regulated by autophagy, supporting the conclusion that autophagy is a promising target in cancer therapy.

Tauroursodeoxycholic acid ameliorates renal injury induced by COL4A3 mutation

COL4A3/A4/A5 mutations have been identified as critical causes of Alport syndrome and other genetic chronic kidney diseases. However, the underlying pathogenesis remains unclear, and specific treatments are lacking. Here, we constructed a transgenic Alport syndrome mouse model by generating a mutation (Col4a3 p.G799R) identified previously from one large Alport syndrome family into mice. We observed that the mutation caused a pathological decrease in intracellular and secreted collagen IV α3α4α5 heterotrimers. The mutant collagen IV α3 chains abnormally accumulated in the endoplasmic reticulum and exhibited defective secretion, leading to persistent endoplasmic reticulum stress in vivo and in vitro. RNA-seq analysis revealed that the MyD88/p38 MAPK pathway plays key roles in mediating subsequent inflammation and apoptosis signaling activation. Treatment with tauroursodeoxycholic acid, a chemical chaperone drug that functions as an endoplasmic reticulum stress inhibitor, effectively suppressed endoplasmic reticulum stress, promoted secretion of the α3 chains, and inhibited the activation of the MyD88/p38 MAPK pathway. Tauroursodeoxycholic acid treatment significantly improved kidney function in vivo. These results partly clarified the pathogenesis of kidney injuries associated with Alport syndrome, especially in glomeruli, and suggested that tauroursodeoxycholic acid might be useful for the early clinical treatment of Alport syndrome.

Leukolectins support lifelong innate immunity in lower vertebrates, and reveal dichotomies of several leukocytic lineages

Innate immunity is vital for animal homeostasis and survival. First-line immuno-defense for fish larvae involves mucus enriched with leukolectin (LL) secreted by dermal lectocytes. Later during the critical transition from yolk-nutrition to feeding, additional larval immuno-protection in zebrafish (zF) is provided by macrophages containing LL (lectophages). This work investigated new LL-expression in embryos and in blood, structures of fish leukocytic LL and LL-genes, and LL-presence in chicken leukocytes. In zF-embryos, lectophages appear ∼10 hpf, while later, cells co-expressing myeloperoxidase- and LL-mRNA were detected (∼19 hpf). Furthermore, protein-extracts of Atlantic salmon (Ssal) leukocytes contained LL-proteins, compartmentalized in the cytosol. Cloning and sequencing revealed 94 % nt-sequence identity between variants of Ssal-leukolectins. Highly conserved LLs allowed production of epitope-specific anti-LL IgGs. Immuno-fluorescence-analysis demonstrated that most Ssal-bloodcells were LL-negative, but both some large cells with protrusions and some small, rounded cells did express LL. Immunoperoxidase-staining method confirmed LL-expression in some Ssal-leukocytes, identified as macrophages, PMN-leukocytes, thrombocytes and dendritic cells. However, closer examination revealed a dichotomy of these cell-categories into either LL-positive, or LL-negative variants. In situ hybridization demonstrated profuse LL-expression in Ssal head kidney interstitial tissue, while LL-transcripts were absent in large kidney tubules. Both hematopoietic (non-pigmented) marrow cells and melano-macrophages expressed LL-mRNA, implying that leukolectins provide lifelong innate immuno-protection. PCR-amplification using Ssal-leukocytic DNA as template, and direct sequencing yielded a leukocytic ll-gene. Some cells in salmon, cod, halibut, oikopleura and zebrafish embryos express LL-proteins and/or LL-mRNA, and LL-mRNA is detected in salmon, cod and chicken leukocytes. However, current genomes for these species lack recognizable LL-loci except the Ssal_v3.1 Genome-assembly. The data demonstrate an unexpected dichotomy of some leukocyte lineages into LL-positive or LL-negative cell-variants. Such dichotomies suggest exploring differential impacts from the duplicated leukocyte-lineages in health and disease.

Recent Advances in Photodynamic Therapy: Metal-Based Nanoparticles as Tools to Improve Cancer Therapy

Cancer remains a significant global health challenge, with traditional therapies like surgery, chemotherapy, and radiation often accompanied by systemic toxicity and damage to healthy tissues. Despite progress in treatment, these approaches have limitations such as non-specific targeting, systemic toxicity, and resistance development in cancer cells. In recent years, nanotechnology has emerged as a revolutionary frontier in cancer therapy, offering potential solutions to these challenges. Nanoparticles, due to their unique physical and chemical properties, can carry therapeutic payloads, navigate biological barriers, and selectively target cancer cells. Metal-based nanoparticles, in particular, offer unique properties suitable for various therapeutic applications. Recent advancements have focused on the integration of metal-based nanoparticles to enhance the efficacy and precision of photodynamic therapy. Integrating nanotechnology into cancer therapy represents a paradigm shift, enabling the development of strategies with enhanced specificity and reduced off-target effects. This review aims to provide a comprehensive understanding of the pivotal role of metal-based nanoparticles in photodynamic therapy. We explore the mechanisms, biocompatibility, and applications of metal-based nanoparticles in photodynamic therapy, highlighting the challenges and the limitations in their use, as well as the combining of metal-based nanoparticles/photodynamic therapy with other strategies as a synergistic therapeutic approach for cancer treatment.

Hepatocyte programmed cell death: the trigger for inflammation and fibrosis in metabolic dysfunction-associated steatohepatitis

By replacing and removing defective or infected cells, programmed cell death (PCD) contributes to homeostasis maintenance and body development, which is ubiquitously present in mammals and can occur at any time. Besides apoptosis, more novel modalities of PCD have been described recently, such as necroptosis, pyroptosis, ferroptosis, and autophagy-dependent cell death. PCD not only regulates multiple physiological processes, but also participates in the pathogenesis of diverse disorders, including metabolic dysfunction-associated steatotic liver disease (MASLD). MASLD is mainly classified into metabolic dysfunction-associated steatotic liver (MASL) and metabolic dysfunction-associated steatohepatitis (MASH), and the latter putatively progresses to cirrhosis and hepatocellular carcinoma. Owing to increased incidence and obscure etiology of MASH, its management still remains a tremendous challenge. Recently, hepatocyte PCD has been attracted much attention as a potent driver of the pathological progression from MASL to MASH, and some pharmacological agents have been proved to exert their salutary effects on MASH partly via the regulation of the activity of hepatocyte PCD. The current review recapitulates the pathogenesis of different modalities of PCD, clarifies the mechanisms underlying how metabolic disorders in MASLD induce hepatocyte PCD and how hepatocyte PCD contributes to inflammatory and fibrotic progression of MASH, discusses several signaling pathways in hepatocytes governing the execution of PCD, and summarizes some potential pharmacological agents for MASH treatment which exert their therapeutic effects partly via the regulation of hepatocyte PCD. These findings indicate that hepatocyte PCD putatively represents a new therapeutic point of intervention for MASH.

Developing a Tanshinone IIA Memetic by Targeting MIOS to Regulate mTORC1 and Autophagy in Glioblastoma

Tanshinone IIA (T2A) is a bioactive compound that provides promise in the treatment of glioblastoma multiforme (GBM), with a range of molecular mechanisms including the inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) and the induction of autophagy. Recently, T2A has been demonstrated to function through sestrin 2 (SESN) to inhibit mTORC1 activity, but its possible impact on autophagy through this pathway has not been investigated. Here, the model system Dictyostelium discoideum and GBM cell lines were employed to investigate the cellular role of T2A in regulating SESN to inhibit mTORC1 and activate autophagy through a GATOR2 component MIOS. In D. discoideum, T2A treatment induced autophagy and inhibited mTORC1 activity, with both effects lost upon the ablation of SESN (sesn-) or MIOS (mios-). We further investigated the targeting of MIOS to reproduce this effect of T2A, where computational analysis identified 25 novel compounds predicted to strongly bind the human MIOS protein, with one compound (MIOS inhibitor 3; Mi3) reducing cell proliferation in two GBM cells. Furthermore, Mi3 specificity was demonstrated through the loss of potency in the D. discoideum mios- cells regarding cell proliferation and the induction of autophagy. In GBM cells, Mi3 treatment also reduced mTORC1 activity and induced autophagy. Thus, a potential T2A mimetic showing the inhibition of mTORC1 and induction of autophagy in GBM cells was identified.

Therapeutic Relevance of Inducing Autophagy in β-Thalassemia

The β-thalassemias are inherited genetic disorders affecting the hematopoietic system. In β-thalassemias, more than 350 mutations of the adult β-globin gene cause the low or absent production of adult hemoglobin (HbA). A clinical parameter affecting the physiology of erythroid cells is the excess of free α-globin. Possible experimental strategies for a reduction in excess free α-globin chains in β-thalassemia are CRISPR-Cas9-based genome editing of the β-globin gene, forcing "de novo" HbA production and fetal hemoglobin (HbF) induction. In addition, a reduction in excess free α-globin chains in β-thalassemia can be achieved by induction of the autophagic process. This process is regulated by the Unc-51-like kinase 1 (Ulk1) gene. The interplay with the PI3K/Akt/TOR pathway, with the activity of the α-globin stabilizing protein (AHSP) and the involvement of microRNAs in autophagy and Ulk1 gene expression, is presented and discussed in the context of identifying novel biomarkers and potential therapeutic targets for β-thalassemia.

Investigating autophagy and intricate cellular mechanisms in hepatocellular carcinoma: Emphasis on cell death mechanism crosstalk

Hepatocellular carcinoma (HCC) stands as a formidable global health challenge due to its prevalence, marked by high mortality and morbidity rates. This cancer type exhibits a multifaceted etiology, prominently linked to viral infections, non-alcoholic fatty liver disease, and genomic mutations. The inherent heterogeneity of HCC, coupled with its proclivity for developing drug resistance, presents formidable obstacles to effective therapeutic interventions. Autophagy, a fundamental catabolic process, plays a pivotal role in maintaining cellular homeostasis, responding to stressors such as nutrient deprivation. In the context of HCC, tumor cells exploit autophagy, either augmenting or impeding its activity, thereby influencing tumorigenesis. This comprehensive review underscores the dualistic role of autophagy in HCC, acting as both a pro-survival and pro-death mechanism, impacting the trajectory of tumorigenesis. The anti-carcinogenic potential of autophagy is evident in its ability to enhance apoptosis and ferroptosis in HCC cells. Pertinently, dysregulated autophagy fosters drug resistance in the carcinogenic context. Both genomic and epigenetic factors can regulate autophagy in HCC progression. Recognizing the paramount importance of autophagy in HCC progression, this review introduces pharmacological compounds capable of modulating autophagy-either inducing or inhibiting it, as promising avenues in HCC therapy.

Autophagy in Its (Proper) Context: Molecular Basis, Biological Relevance, Pharmacological Modulation, and Lifestyle Medicine

Autophagy plays a critical role in maintaining cellular homeostasis and responding to various stress conditions by the degradation of intracellular components. In this narrative review, we provide a comprehensive overview of autophagy's cellular and molecular basis, biological significance, pharmacological modulation, and its relevance in lifestyle medicine. We delve into the intricate molecular mechanisms that govern autophagy, including macroautophagy, microautophagy and chaperone-mediated autophagy. Moreover, we highlight the biological significance of autophagy in aging, immunity, metabolism, apoptosis, tissue differentiation and systemic diseases, such as neurodegenerative or cardiovascular diseases and cancer. We also discuss the latest advancements in pharmacological modulation of autophagy and their potential implications in clinical settings. Finally, we explore the intimate connection between lifestyle factors and autophagy, emphasizing how nutrition, exercise, sleep patterns and environmental factors can significantly impact the autophagic process. The integration of lifestyle medicine into autophagy research opens new avenues for promoting health and longevity through personalized interventions.

Distinct roles of core autophagy-related genes in zebrafish definitive hematopoiesis

Despite the well-described discrepancy between ATG (macroautophagy/autophagy-related) genes in the regulation of hematopoiesis, varying essentiality of core ATG proteins in vertebrate definitive hematopoiesis remains largely unclear. Here, we employed zebrafish (Danio rerio) to compare the functions of six core atg genes, including atg13, becn1 (beclin1), atg9a, atg2a, atg5, and atg3, in vertebrate definitive hematopoiesis via clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 ribonucleoprotein and morpholino targeting. Zebrafish with various atg mutations showed autophagic deficiency and presented partially consistent hematopoietic abnormalities during early development. All six atg mutations led to a declined number of spi1b+ (Spi-1 proto-oncogene b) myeloid progenitor cells. However, only becn1 mutation resulted in the expansion of myb+ (v-myb avian myeloblastosis viral oncogene homolog) hematopoietic stem and progenitor cells (HSPCs) and transiently increased coro1a+ (coronin, actin binding protein, 1A) leukocytes, whereas atg3 mutation decreased the number of HSPCs and leukocytes. Proteomic analysis of caudal hematopoietic tissue identified sin3aa (SIN3 transcription regulator family member Aa) as a potential modulator of atg13- and becn1-regulated definitive hematopoiesis. Disruption of sin3aa rescued the expansion of HSPCs and leukocytes in becn1 mutants and exacerbated the decrease of HSPCs in atg13 mutants. Double mutations were also performed to examine alternative functions of various atg genes in definitive hematopoiesis. Notably, becn1 mutation failed to induce HSPCs expansion with one of the other five atg mutations. These findings demonstrated the distinct roles of atg genes and their interplays in zebrafish definitive hematopoiesis, thereby suggesting that the vertebrate definitive hematopoiesis is regulated in an atg gene-dependent manner.Abbreviations: AGM: aorta-gonad-mesonephros; AO: acridine orange; atg: autophagy related; becn1: beclin 1, autophagy related; CHT: caudal hematopoietic tissue; CKO: conditional knockout; coro1a: coronin, actin binding protein, 1A; CQ: chloroquine; CRISPR: clustered regularly interspaced short palindromic repeats; dpf: days post fertilization; FACS: fluorescence-activated cell sorting; hbae1.1: hemoglobin, alpha embryonic 1.1; HSCs: hematopoietic stem cells; HSPCs: hematopoietic stem and progenitor cells; KD: knockdown; KO: knockout; map1lc3/lc3: microtubule-associated protein 1 light chain 3; MO: morpholino; mpeg1.1: macrophage expressed 1, tandem duplicate 1; mpx: myeloid-specific peroxidase; myb: v-myb avian myeloblastosis viral oncogene homolog; PE: phosphatidylethanolamine; p-H3: phospho-H3 histone; PtdIns3K: class 3 phosphatidylinositol 3-kinase; rag1: recombination activating 1; rb1cc1/fip200: RB1-inducible coiled-coil 1; RFLP: restriction fragment length polymorphism; RNP: ribonucleoprotein; sin3aa: SIN3 transcription regulator family member Aa; spi1b: Spi-1 proto-oncogene b; ulk: unc-51 like autophagy activating kinase; vtg1: vitellogenin 1; WISH: whole-mount in situ hybridization.

PFOS exposure destroys the integrity of the blood-testis barrier (BTB) through PI3K/AKT/mTOR-mediated autophagy

Perfluorooctanesulfonate or perfluorooctane sulfonic acid (PFOS), a type of perfluorinated compound, is mainly found in consumer products. Exposure to PFOS could cause male reproductive toxicity by causing injury to the blood-testis barrier (BTB). However, the specific mechanisms through which PFOS affects male reproduction remain unclear. The mammalian target of rapamycin (mTOR) is a vital protein kinase that is believed to be a central regulator of autophagy. In this study, we established in vivo and in vitro models to explore the effects of PFOS on the BTB, autophagy, and the regulatory role of the mTOR signaling pathway. Adult mice were developmentally exposed to 0, 0.5, 5, and 10 mg/kg/day PFOS for five weeks. Thereafter, their testicular morphology, sperm counts, serum testosterone, expression of BTB-related proteins, and autophagy-related proteins were evaluated. Additionally, TM4 cells (a mouse Sertoli cell line) were used to delineate the molecular mechanisms that mediate the effects of PFOS on BTB. Our results demonstrated that exposure to PFOS induced BTB injury and autophagy, as evidenced by increased expression of autophagy-related proteins, accumulation of autophagosomes, observed through representative electron micrographs, and decreased activity of the PI3K/AKT/mTOR pathway. Moreover, treatment with chloroquine, an autophagy inhibitor, alleviated the effects of PFOS on the integrity of TM4 cells in the BTB and the PI3K/AKT/mTOR pathway. Overall, this study highlights that exposure to PFOS destroys the integrity of the BTB through PI3K/AKT/mTOR-mediated autophagy.

The Role of Autophagy in Human Uveal Melanoma and the Development of Potential Disease Biomarkers and Novel Therapeutic Paradigms

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.

Autophagy Genes and Otitis Media Outcomes

Otitis media (OM) is a common cause of hearing loss in children that requires corrective surgery. Various studies have investigated the pathomechanisms and treatment of OM. Autophagy, an essential cellular recycling and elimination mechanism implicated in various diseases, is known to play an important role in the pathogenesis of OM. Here, we conducted a literature review on autophagy in OM, highlighting the relationship between expression patterns of autophagy-related factors and pathophysiological and clinical aspects of OM. We summarized the existing research results on the expression of autophagy-related factors in acute OM (AOM), OM with effusion (OME), chronic OM (COM) with cholesteatoma, and COM without cholesteatoma (CholeOM) in animals and humans. Autophagy-related factors are expressed in the middle ear mucosa or fluid of AOM, effusion of OME, granulation tissue of COM, and cholesteatoma of CholeOM. Among ATGs and other autophagy-related factors, the most extensively studied in relation to the pathogenesis of OM are mTOR, LC3II/I, PI3K, Beclin-1, FLIP, Akt, and Rubicon. Expression of autophagy-related factors is associated with AOM, OME, COM, and CholeOM. Inadequate expression of these factors or a decrease/increase in autophagy responses can result in OM, underscoring the critical role of ATGs and related factors in the pathogenesis of OM.

Autophagy-related genes polymorphism in hepatitis B virus-associated hepatocellular carcinoma: A systematic review

BACKGROUND

Chronic hepatitis B (CHB) virus is the most common risk factor for developing liver malignancy. Autophagy is an essential element in human cell maintenance. Several studies have demonstrated that autophagy plays a vital role in liver cancer at different stages. In this systematic review, we intend to investigate the role of polymorphism and mutations of autophagy-related genes (ATGs) in the pathogenesis and carcinogenesis of the hepatitis B virus (HBV).

MATERIALS AND METHODS

The search was conducted in online databases (Web of Science, PubMed, and Scopus) using Viruses, Infections, Polymorphism, Autophagy, and ATG. The study was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria.

RESULTS

The primary search results led to 422 studies. By screening and eligibility evaluation, only four studies were relevant. The most important polymorphisms in hepatocellular carcinoma were rs2241880 in ATG16L1, rs77859116, rs510432, and rs548234 in ATG5. Furthermore, some polymorphisms are associated with an increased risk of HBV infection including, rs2241880 in ATG16L1 and rs6568431 in ATG5.

CONCLUSION

The current study highlights the importance of rs2241880 in ATG16L1 and rs77859116, rs510432, and rs548234 in ATG5 for HBV-induced HCC. Additionally, some mutations in ATG16L1 and ATG5 were important in risk of HBV infection. The study highlights the gap of knowledge in the field of ATG polymorphisms in HBV infection and HBV-induced HCC.

Recent advances of vacuolar protein-sorting 34 inhibitors targeting autophagy

Autophagy is a ubiquitous pathological/physiological antioxidant cellular reaction in eukaryotic cells. Vacuolar protein sorting 34 (Vps34 or PIK3C3), which plays a crucial role in autophagy, has received much attention. As the only Class III phosphatidylinositol-3 kinase in mammals, Vps34 participates in vesicular transport, nutrient signaling and autophagy. Dysfunctionality of Vps34 induces carcinogenesis, and abnormal autophagy mediated by dysfunction of Vps34 is closely related to the pathological progression of various human diseases, which makes Vps34 a novel target for tumor immunotherapy. In this review, we summarize the molecular mechanisms underlying macroautophagy, and further discuss the structure-activity relationship of Vps34 inhibitors that have been reported in the past decade as well as their potential roles in anticancer immunotherapy to better understand the antitumor mechanism underlying the effects of these inhibitors.

Inhibition of Autophagy Aggravates Arachis hypogaea L. Skin Extracts-Induced Apoptosis in Cancer Cells

The skin of Arachis hypogaea L. (peanut or groundnut) is a rich source of polyphenols, which have been shown to exhibit a wider spectrum of noteworthy biological activities, including anticancer effects. However, the anticancer activity of peanut skin extracts against melanoma and colorectal cancer (CRC) cells remains elusive. In this study, we systematically investigated the cytotoxic, antiproliferative, pro-apoptotic, and anti-migration effects of peanut skin ethanolic extract and its fractions on melanoma and CRC cells. Cell viability results showed that the ethyl acetate fraction (AHE) of peanut skin ethanolic crude extract and one of the methanolic fractions (AHE-2) from ethyl acetate extraction exhibited the highest cytotoxicity against melanoma and CRC cells but not in nonmalignant human skin fibroblasts. AHE and AHE-2 effectively modulated the cell cycle-related proteins, including the suppression of cyclin-dependent kinase 4 (CDK4), cyclin-dependent kinase 6 (CDK6), phosphorylation of Retinoblastoma (p-Rb), E2F1, Cyclin A, and activation of tumor suppressor p53, which was associated with cell cycle arrest and paralleled their antiproliferative efficacies. AHE and AHE-2 could also induce caspase-dependent apoptosis and inhibit migration activities in melanoma and CRC cells. Moreover, it is noteworthy that autophagy, manifested by microtubule-associated protein light chain 3B (LC3B) conversion and the aggregation of GFP-LC3, was detected after AHE and AHE-2 treatment and provided protective responses in cancer cells. Significantly, inhibition of autophagy enhanced AHE- and AHE-2-induced cytotoxicity and apoptosis. Together, these findings not only elucidate the anticancer potential of peanut skin extracts against melanoma and CRC cells but also provide a new insight into autophagy implicated in peanut skin extracts-induced cancer cell death.

Cytotoxic Impact of Naringenin-Loaded Solid Lipid Nanoparticles on RIN5F Pancreatic β Cells via Autophagy Blockage

BACKGROUND

Autophagy plays a crucial role in modulating the proliferation of cancer diseases. However, the application of Naringenin (Nar), a compound with potential benefits against these diseases, has been limited due to its poor solubility and bioavailability.

OBJECTIVE

This study aimed to develop solid lipid nanoparticles (Nar-SLNs) loaded with Nar to enhance their therapeutic impact.

METHODS

In vitro experiments using Rin-5F cells exposed to Nar and Nar-SLNs were carried out to investigate the protective effects of Nar and its nanoformulation against the pancreatic cancer cell line of Rin-5F.

RESULTS

Treatment with Nar and Nar-SLN led to an increase in autophagic markers (Akt, LC3, Beclin1, and ATG genes) and a decrease in the level of miR-21. Both Nar and Nar-SLN treatments inhibited cell proliferation and reduced the expression of autophagic markers. Notably, Nar-SLNs exhibited greater efficacy compared to free Nar.

CONCLUSION

These findings suggest that SLNs effectively enhance the cytotoxic impact of Nar, making Nar-SLNs a promising candidate for suppressing or preventing Rin-5F cell growth.

Treatment of calcific arterial disease via enhancement of autophagy using GSK343

Vascular calcification is a hallmark of atherosclerotic disease and serves as a strong predictor and risk factor for cardiovascular events. Growing evidence suggests that autophagy may play a protective role in early atherosclerosis. The precise effects of autophagy on VSMC-mediated calcification remain unknown. In this study, we utilized multi-omic profiling to investigate impaired autophagy at the transcriptional level as a key driver of VSMC calcification. Our findings revealed that impaired autophagy is an essential determinant of VSMC calcification. We observed that an osteogenic environment affects the open chromatin status of VSMCs, compromising the transcriptional activation of autophagy initiation genes. In vivo experiments involve pharmacological and genetic activation of autophagy using mouse models of spontaneous large (Mgp-/-) and small (Abcc6-/-) artery calcification. Taken together, these data advance our mechanistic understanding of vascular calcification and provide important insights for a broad range of cardiovascular diseases involving VSMC phenotype switch.

Autophagy Receptor-Inspired Antibody-Fusion Proteins for Targeted Intracellular Degradation

Autophagy is responsible for the degradation of large intracellular contents, such as unwanted protein aggregates and organelles. Impaired autophagy can therefore lead to the accumulation of pathological aggregates, correlating with aging and neurodegenerative diseases. However, a broadly applicable methodology is not available for the targeted degradation of protein aggregates or organelles in mammalian cells. Herein, we developed a series of autophagy receptor-inspired targeting chimeras (AceTACs) that can induce the targeted degradation of aggregation-prone proteins and protein aggregates (e.g., huntingtin, TDP-43, and FUS mutants), as well as organelles (e.g., mitochondria, peroxisomes, and endoplasmic reticulum). These antibody-fusion-based AceTAC degraders were designed to mimic the function of autophagy receptors, simultaneously binding with the cellular targets and the LC3 proteins on the autophagosomal membrane, eventually transporting the target to the autophagy-lysosomal process for degradation. The AceTAC degradation system provides design principles for antibody-based degradation through autophagy, largely expanding the scope of intracellular targeted degradation technologies.

Vitamin D and autophagy in knee osteoarthritis: A review

Knee osteoarthritis (KOA), the highly prevalent degenerative disease affecting the joint, perpetually devastates the health of the elderly. Of various mechanisms known to participate in KOA etiology, apoptosis of chondrocytes is widely regarded as the primary cause of cartilage degradation. It has been suggested that the induction of autophagy in chondrocytes could potentially prolong the progression of KOA by modulating intracellular metabolic processes, which may be helpful for ameliorating chondrocyte apoptosis and eventual cartilage degeneration. Autophagy, a physiological process characterized by intracellular self-degradation, has been reportedly implicated in various pathologic conditions including KOA. Interestingly, vitamin D has been shown to regulate autophagy in human chondrocytes through multiple pathways, specifically AMPK/mTOR signaling pathway. This observation underscores the potential of vitamin D as a novel approach for restoring the functionality and survivability of chondrocytes in KOA. Supporting vitamin D's clinical significance, previous studies have demonstrated its substantial involvement in the symptoms and irregular joint morphology observed in KOA patients, strengthening potential therapeutic efficacy of vitamin D in treatment of KOA. Herein, the purpose of this review was to determine the mechanisms underlying the multi-processes of vitamin D implicated in autophagy in several cells including chondrocytes, which would bring unique insights into KOA pathogenesis.

Targeting Mitochondrial Sirtuins in Age-Related Neurodegenerative Diseases and Fibrosis

Aging is a natural and complex biological process that is associated with widespread functional declines in numerous physiological processes, terminally affecting multiple organs and tissues. Fibrosis and neurodegenerative diseases (NDs) often occur with aging, imposing large burdens on public health worldwide, and there are currently no effective treatment strategies for these diseases. Mitochondrial sirtuins (SIRT3-5), which are members of the sirtuin family of NAD+-dependent deacylases and ADP-ribosyltransferases, are capable of regulating mitochondrial function by modifying mitochondrial proteins that participate in the regulation of cell survival under various physiological and pathological conditions. A growing body of evidence has revealed that SIRT3-5 exert protective effects against fibrosis in multiple organs and tissues, including the heart, liver, and kidney. SIRT3-5 are also involved in multiple age-related NDs, including Alzheimer's disease, Parkinson's disease, and Huntington's disease. Furthermore, SIRT3-5 have been noted as promising targets for antifibrotic therapies and the treatment of NDs. This review systematically highlights recent advances in knowledge regarding the role of SIRT3-5 in fibrosis and NDs and discusses SIRT3-5 as therapeutic targets for NDs and fibrosis.

Potential implications of protein kinase Cα in pathophysiological conditions and therapeutic interventions

PKCα is a molecule with many functions that play an important role in cell survival and death to maintain cellular homeostasis. Alteration in the normal functioning of PKCα is responsible for the complicated etiology of many pathologies, including cancer, cardiovascular diseases, kidney complications, neurodegenerative diseases, diabetics, and many others. Several studies have been carried out over the years on this kinase's function, and regulation in normal physiology and pathological conditions. A lot of data with antithetical results have therefore accumulated over time to create a complex framework of physiological implications connected to the PKCα function that needs comprehensive elucidation. In light of this information, we critically analyze the multiple roles played by PKCα in basic cellular processes and their molecular mechanism during various pathological conditions. This review further discusses the current approaches to manipulating PKCα signaling amplitude in the patient's favour and proposed PKCα as a therapeutic target to reverse pathological states.

EnsembleDL-ATG: Identifying autophagy proteins by integrating their sequence and evolutionary information using an ensemble deep learning framework

Autophagy is a primary mechanism for maintaining cellular homeostasis. The synergistic actions of autophagy-related (ATG) proteins strictly regulate the whole autophagic process. Therefore, accurate identification of ATGs is a first and critical step to reveal the molecular mechanism underlying the regulation of autophagy. Current computational methods can predict ATGs from primary protein sequences, but owing to the limitations of algorithms, significant room for improvement still exists. In this research, we propose EnsembleDL-ATG, an ensemble deep learning framework that aggregates multiple deep learning models to predict ATGs from protein sequence and evolutionary information. We first evaluated the performance of individual networks for various feature descriptors to identify the most promising models. Then, we explored all possible combinations of independent models to select the most effective ensemble architecture. The final framework was built and maintained by an organization of four different deep learning models. Experimental results show that our proposed method achieves a prediction accuracy of 94.5 % and MCC of 0.890, which are nearly 4 % and 0.08 higher than ATGPred-FL, respectively. Overall, EnsembleDL-ATG is the first ATG machine learning predictor based on ensemble deep learning. The benchmark data and code utilized in this study can be accessed for free at https://github.com/jingry/autoBioSeqpy/tree/2.0/examples/EnsembleDL-ATG.

Roles of Stress Response in Autophagy Processes and Aging-Related Diseases

The heat shock factor 1 (HSF1)-mediated stress response pathway and autophagy processes play important roles in the maintenance of proteostasis. Autophagy processes are subdivided into three subtypes: macroautophagy, chaperone-mediated autophagy (CMA), and microautophagy. Recently, molecular chaperones and co-factors were shown to be involved in the selective degradation of substrates by these three autophagy processes. This evidence suggests that autophagy processes are regulated in a coordinated manner by the HSF1-mediated stress response pathway. Recently, various studies have demonstrated that proteostasis pathways including HSF1 and autophagy are implicated in longevity. Furthermore, they serve as therapeutic targets for aging-related diseases such as cancer and neurodegenerative diseases. In the future, these studies will underpin the development of therapies against various diseases.

Atg2 Regulates Cellular and Humoral Immunity in Drosophila

Autophagy is a process that promotes the lysosomal degradation of cytoplasmic proteins and is highly conserved in eukaryotic organisms. Autophagy maintains homeostasis in organisms and regulates multiple developmental processes, and autophagy disruption is related to human diseases. However, the functional roles of autophagy in mediating innate immune responses are largely unknown. In this study, we sought to understand how Atg2, an autophagy-related gene, functions in the innate immunity of Drosophila melanogaster. The results showed that a large number of melanotic nodules were produced upon inhibition of Atg2. In addition, inhibiting Atg2 suppressed the phagocytosis of latex beads, Staphylococcus aureus and Escherichia coli; the proportion of Nimrod C1 (one of the phagocytosis receptors)-positive hemocytes also decreased. Moreover, inhibiting Atg2 altered actin cytoskeleton patterns, showing longer filopodia but with decreased numbers of filopodia. The expression of AMP-encoding genes was altered by inhibiting Atg2. Drosomycin was upregulated, and the transcript levels of Attacin-A, Diptericin and Metchnikowin were decreased. Finally, the above alterations caused by the inhibition of Atg2 prevented flies from resisting invading pathogens, showing that flies with low expression of Atg2 were highly susceptible to Staphylococcus aureus and Erwinia carotovora carotovora 15 infections. In conclusion, Atg2 regulated both cellular and humoral innate immunity in Drosophila. We have identified Atg2 as a crucial regulator in mediating the homeostasis of immunity, which further established the interactions between autophagy and innate immunity.

Role of heparanase in sepsis‑related acute kidney injury (Review)

Sepsis-related acute kidney injury (S-AKI) is a common and significant complication of sepsis in critically ill patients, which can often only be treated with antibiotics and medications that reduce S-AKI symptoms. The precise mechanism underlying the onset of S-AKI is still unclear, thus hindering the development of new strategies for its treatment. Therefore, it is necessary to explore the pathogenesis of S-AKI to identify biomarkers and therapeutic targets for its early diagnosis and treatment. Heparanase (HPA), the only known enzyme that cleaves the side chain of heparan sulfate, has been widely studied in relation to tumor metabolism, procoagulant activity, angiogenesis, inflammation and sepsis. It has been reported that HPA plays an important role in the progression of S-AKI. The aim of the present review was to provide an overview of the function of HPA in S-AKI and to summarize its underlying molecular mechanisms, including mediating inflammatory response, immune response, autophagy and exosome biogenesis. It is anticipated that emerging discoveries about HPA in S-AKI will support HPA as a potential biomarker and therapeutic target to combat S-AKI.

LncRNA 220: A Novel Long Non-Coding RNA Regulates Autophagy and Apoptosis in Kupffer Cells via the miR-5101/PI3K/AKT/mTOR Axis in LPS-Induced Endotoxemic Liver Injury in Mice

Sepsis is a severe medical condition distinguished by immune systematic dysfunction and multiple organic injury, or even failure, resulting from an acute systemic inflammatory response. Acute liver injury (ALI) could be considered as a notable inflammatory outcome of sepsis. Studies have demonstrated the essential roles played by long non-coding RNAs (lncRNAs) in mediating the processes of various diseases, including their ability to engage in interactions with microRNAs (miRNAs) as complexes of competing endogenous RNA (ceRNA) to modulate signaling pathways. In this study, a newly discovered lncRNA, named 220, was identified to function in regulating autophagy and apoptosis in Kupffer cells treated with lipopolysaccharide (LPS). This was achieved through sponging miR-5101 as a ceRNA complex, as identified via high-throughput sequencing. The expression of 220 was found to be significantly different in the hepatic tissues of endotoxemic mice that were treated with LPS for 8 h, ultimately modulating the ALI process. Our studies have collectively demonstrated that 220 is a novel regulator that acts on LPS-induced autophagy and apoptosis in Kupffer cells, thereby mediating the ALI process induced by LPS. Furthermore, the validation of our findings using clinical databases suggests that 220 could potentially serve as a molecular target of clinical, diagnostic, and therapeutic significance in septic liver injury.

Ratiometric and discriminative visualization of autophagic processes with a novel dual-responded lysosome-specific fluorescent probe

BACKGROUND

Autophagy is a critical self-eating pathway involved in numerous physiological and pathological processes. Lysosomal degradation of dysfunctional organelles and invading microorganisms is central to the autophagy mechanism and essential for combating disease-related conditions. Therefore, monitoring fluctuations in the lysosomal microenvironment is vital for tracking the dynamic process of autophagy. Although much effort has been put into designing probes for measuring lysosomal viscosity or pH separately, there is a need to validate the concurrent imaging of the two elements to enhance the understanding of the dynamic progression of autophagy.

METHODS

Probe HFI was synthesized in three steps and was developed to visualize changes in viscosity and pH within lysosomes for real-time autophagy tracking. Then, the spectrometric determination was carried out. Next, the probe was applied to image autophagy in cells under nutrient-deprivation or external stress. Additionally, the performance of HFI to monitor autophagy was employed to evaluate acetaminophen-induced liver injury.

RESULTS

We constructed a ratiometric dual-responsive probe, HFI, with a large Stokes shift over 200 nm, dual-wavelength emission, and small background interference. The ratiometric fluorescent signal (R = I ₆₁₀/I ₄₆₀) of HFI had an excellent correlation with both viscosity and pH. More importantly, high viscosity and low pH had a synergistic promotion effect on the emission intensity of HFI, which enabled it to specially lit lysosomes without disturbing the inherent microenvironment. We then successfully used HFI to monitor intracellular autophagy induced by starvation or drugs in real-time. Interestingly, HFI also enabled us to visualize the occurrence of autophagy in the liver tissue of a DILI model, as well as the reversible effect of hepatoprotective drugs on this event.

CONCLUSIONS

In this study, we developed the first ratiometric dual-responsive fluorescent probe, HFI, for real-time revealing autophagic details. It could image lysosomes with minimal perturbation to their inherent pH, allowing us to track changes in lysosomal viscosity and pH in living cells. Ultimately, HFI has great potential to serve as a useful indicator for autophagic changes in viscosity and pH in complex biological samples and can also be used to assess drug safety.

The protective effects of melatonin in high glucose environment by alleviating autophagy and apoptosis on primary cortical neurons

Cognitive dysfunction has been regarded as a complication of diabetes. Melatonin (MLT) shows a neuroprotective effect on various neurological diseases. However, its protective effect on cortical neurons in high glucose environment has not been reported. Our present study aims to observe the protective effect of melatonin on rat cortical neurons and its relationship with autophagy in high glucose environment. The rat primary cortical neurons injury model was induced by high glucose. The CCK-8, flow cytometry, Western blot and immunofluorescence methods were used to examine the cell viability, apoptosis rate and proteins expression. Our results showed that there were no differences in cell viability, apoptosis rate, and protein expression among the control, MLT and mannitol group. The cell viability of the glucose group was significantly lower than that of the control group, and the apoptosis rate of the glucose group was significantly higher than that of the control group. Compared with the glucose group, the glucose + melatonin group showed a significant increase in cell viability and a notable decrease in apoptosis rate. Melatonin concentration of 0.1-1 mmol/L can significantly alleviate the injury of cortical neurons caused by high glucose. Compared with the control group, the glucose group showed a significant reduction of B-cell lymphoma 2 (Bcl-2) protein expression, while remarkable elevations of Bcl2-associated X protein (Bax), cleaved Caspase-3, coiled-coil, myosin-like Bcl2-interacting protein (Beclin-1) and microtubule-associated protein 1 light chain-3B type II (LC3B-II) levels. The neurons pre-administered with melatonin obtained significantly reversed these changes induced by high glucose. The phosphorylation levels of protein kinase B (Akt), mechanistic target of rapamycin kinase (mTOR) and Unc-51 like autophagy activating kinase 1(ULK1) were decreased in the glucose group compared with the control group, whereas significant increase were observed in the glucose + MLT group, compared with the glucose group. These data indicated that melatonin has a neuroprotective effect on cortical neurons under high glucose environment, which may work by activating Akt/mTOR/ULK1 pathway and may be deeply associated with the downregulation of autophagy.

Cardiovascular Protection by Metformin: Latest Advances in Basic and Clinical Research

BACKGROUND

Metformin is among the most frequently prescribed antidiabetic drugs worldwide and remains the first-line therapy for type 2 diabetes due to its well-established glucose-lowering efficacy and favorable safety profile.

SUMMARY

Studies over the past decades show that metformin also exerts many other beneficial effects independent of its glucose-lowering effect both in experimental models and human subjects. Among them, the most notable is its cardiovascular protective effect. In this review, we discuss the latest cutting-edge research findings on metformin's cardiovascular protection from both preclinical studies and randomized clinical trials. We focus on describing novel basic research discoveries reported in influential journals and discussing their implications in the context of latest clinical trial findings related to common cardiovascular and metabolic disorders, including atherosclerosis and dyslipidemia, myocardial injury, and heart failure.

KEY MESSAGES

While substantial preclinical and clinical evidence suggests metformin as a potential cardiovascular protectant, large-scale randomized controlled trials are warranted to establish its clinical efficacy in treating patients with atherosclerotic cardiovascular disease and heart failure.

The mechanisms and diagnostic potential of lncRNAs, miRNAs, and their related signaling pathways in cervical cancer

Cervical cancer (CC), the fourth most prevalent type of cancer among women worldwide, is associated with high rates of morbidity and mortality. Due to the long period of latency in CC, most patients are already in the middle to late stages when initially diagnosed, which greatly reduces the clinical cure rate and quality of survival, thus resulting in poor outcomes. In recent years, with continuous exploration in the fields of bioinformatics and molecules, it has been found that ncRNAs, including miRNAs and lncRNAs, without the ability to translate proteins are capable of activating or inhibiting certain signaling pathways by targeting and modulating the level of expression of proteins involved in these signaling pathways. ncRNAs play important roles in assisting with diagnosis, drug administration, and prediction of prognosis during CC progression. As an entry point, the mechanisms of interaction between miRNAs, lncRNAs, and signaling pathways have long been a focus in basic research relating to CC, and numerous experimental studies have confirmed the close relationship of miRNAs, lncRNAs, and signaling pathways with CC development. Against this background, we summarize the latest advances in the involvement of lncRNA- and miRNA-related signaling pathways in the development of CC to provide guidance for CC treatment.

Inhibition of autophagy in macrophage promotes IL-1β-mediated hepatocellular carcinoma progression via inflammasome accumulation and self-recruitment

Hepatocellular carcinoma (HCC) has a complex and changeable tumor microenvironment. Despite emerging evidence focusing on autophagy process within immune cells, the function and regulatory mechanism of macrophage autophagy in tumor progression remains unclear. Our results of multiplex-immunohistochemistry and RNA-sequencing identified the reduced levels of autophagy in tumor macrophages in the HCC microenvironment, associated with a poor prognosis and increased microvascular metastasis in HCC patients. Specifically, HCC suppressed the macrophage autophagy initiation through the up-regulation of mTOR and ULK1 phosphorylation at Ser757. Knockdown of autophagy-related proteins to further inhibit autophagy significantly boosted the metastatic potential of HCC. Mechanistically, the accumulation of NLRP3 inflammasome mediated by autophagy inhibition promoted the cleavage, maturation, and release of IL-1β, which facilitated the HCC progression, eventually accelerating HCC metastasis via the epithelial-mesenchymal transition. Autophagy inhibition provoked macrophage self-recruitment through the CCL20-CCR6 signaling was also a crucial account of HCC progression. Recruited macrophages mediated the cascade amplification of IL-1β and CCL20 to form a novel pro-metastatic positive feedback loop through promoting HCC metastasis and increased macrophage recruitment, respectively. Notably, targeting IL-1β/IL-1 receptor signaling impaired lung metastasis induced by macrophage autophagy inhibition in a mice HCC lung metastasis model. In summary, this study highlighted that inhibition of tumor macrophage autophagy facilitated HCC progression by increasing IL-1β secretion via NLRP3 inflammasome accumulation and by macrophage self-recruitment through the CCL20 signaling pathway. Interruption of this metastasis-promoting loop by IL-1β blockade may provide a promising therapeutic strategy for HCC patients.