Regulation Of Autophagy In Cells Research Articles

Research Progress on the Pharmacological Mechanism of Traditional Chinese Medicine Danshen in the Treatment of Cerebral Ischemic Stroke

Cerebral ischemic stroke (CIS) is an acute cerebrovascular disease characterized by focal neurological deficits. Many modern scholars believe that the pathogenesis of CIS is related to factors such as endothelial injury, oxidative stress imbalance, neuroinflammation, cell apoptosis and autophagy, calcium overload, and excessive accumulation of oxygen free radicals. Traditional Chinese medicine believes that the pathogenesis of CIS is obstructed meridians, phlegm and blood stasis, and obstruction of the brain and orifices. Danshen, as a commonly used traditional Chinese medicine in clinical practice, has the effects of promoting blood circulation and removing blood stasis, unblocking meridians and relieving pain, clearing the heart and eliminating restlessness, cooling blood and eliminating carbuncle. In addition, modern pharmacological research has found that the specific pharmacological components of Salvia miltiorrhiza include tanshinone, salvianolic acid, shikimic acid, danshensu, protocatechualdehyde, etc. It has antioxidant stress, regulation of cell autophagy, anti-inflammatory factors, antiplatelet aggregation, and protection of vascular endothelium. This article aims to analyze and summarize the pharmacological mechanism of salvia miltiorrhiza in treating CIS, providing scientific basis for clinical application of salvia miltiorrhiza in treating CIS.

Autophagy: Are Amino Acid Signals Dependent on the mTORC1 Pathway or Independent?

Autophagy is a kind of "self-eating" phenomenon that is ubiquitous in eukaryotic cells. It mainly manifests in the damaged proteins or organelles in the cell being wrapped and transported by the autophagosome to the lysosome for degradation. Many factors cause autophagy in cells, and the mechanism of nutrient-deficiency-induced autophagy has been a research focus. It has been reported that amino-acid-deficiency-induced cellular autophagy is mainly mediated through the mammalian rapamycin target protein complex 1 (mTORC1) signaling pathway. In addition, some researchers also found that non-mTORC1 signaling pathways also regulate autophagy, and the mechanism of autophagy occurrence induced by the deficiency of different amino acids is not precisely the same. Therefore, this review aims to summarize the process of various amino acids regulating cell autophagy and provide a narrative review on the molecular mechanism of amino acids regulating autophagy.

Stearoyl-CoA desaturase 1 is targeted by EBV-encoded miR-BART20-5p and regulates cell autophagy, proliferation, and migration in EBV-associated gastric cancer.

Epstein-Barr virus (EBV) is the first human oncogenic virus known to express microRNAs (miRNAs), which are closely associated with the development of various tumors, including nasopharyngeal and gastric cancers. Stearoyl-CoA Desaturase 1 (SCD1) is a key enzyme in fatty acid synthesis, highly expressed in numerous tumors, promoting tumor growth and metastasis, making it a potential therapeutic target. In this study, we found that SCD1 expression in EBV-associated gastric cancer (EBVaGC) was significantly lower than in EBV-negative gastric cancer (EBVnGC) at both cellular and tissue levels. In addition, EBV-miR-BART20-5p targets the 3'-UTR of SCD1, downregulating its expression. Moreover, overexpression of SCD1 in EBVaGC cells promoted cell migration and proliferation while inhibiting autophagy. These results suggest that EBV-encoded miRNA-BART20-5p may contribute to EBVaGC progression by targeting SCD1.

Lysine-specific demethylase 1 (LSD1) participate in porcine early embryonic development by regulating cell autophagy and apoptosis through the mTOR signaling pathway

Lysine-specific demethylase 1 (LSD1) stands as the pioneering histone demethylase uncovered, proficient in demethylating H3K4me1/2 and H3K9me1/2, thereby governing transcription and participating in cell apoptosis, proliferation, or differentiation. Nevertheless, the complete understanding of LSD1 during porcine early embryonic development and the underlying molecular mechanism remains unclear. Thus, we investigated the mechanism by which LSD1 plays a regulatory role in porcine early embryos. This study revealed that LSD1 inhibition resulted in parthenogenetic activation (PA) and in vitro fertilization (IVF) embryo arrested the development, and decreased blastocyst quality. Meanwhile, H3K4me1/2 and H3K9me1/2 methylase activity was increased at the 4-cell embryo stage. RNA-seq results revealed that autophagy related biological processes were highly enriched through GO and KEGG pathway analyses when LSD1 inhibition. Further studies showed that LSD1 depletion in porcine early embryos resulted in low mTOR and p-mTOR levels and high autophagy and apoptosis levels. The LSD1 deletion-induced increases in autophagy and apoptosis could be reversed by addition of mTOR activators. We further demonstrated that LSD1 inhibition induced mitochondrial dysfunction and mitophagy. In summary, our research results indicate that LSD1 may regulate autophagy and apoptosis through the mTOR pathway and affect early embryonic development of pigs.

Abstract 5866: TESC mediates resistance to lenvatinib in hepatocellular carcinoma by regulating cell autophagy

Abstract Objective: To investigate the mechanism by which TESC (Tescalcin) induces lenvatinib resistance in hepatocellular carcinoma (HCC) through autophagy mediation. Methods:1) Utilized established liver cancer organoids from over 70 patients for lenvatinib drug sensitivity screening and transcriptome sequencing to identify lenvatinib-resistant genes. 2) Constructed stable TESC overexpression and downregulation liver cancer cell lines. Employed CCK8 assays to plot IC50 drug sensitivity curves, elucidating changes in lenvatinib sensitivity in liver cancer cells after TESC overexpression or downregulation. 3) Used TESC-stable cells to establish subcutaneous tumor models and intrahepatic tumor models in nude mice. After tumor formation, administered lenvatinib orally to observe whether TESC affects liver cancer sensitivity to lenvatinib in vivo. 4) Conducted Western blot (WB) analysis to assess the expression of autophagy-related molecules (LC3B II/I, P62, and Beclin1 proteins) in TESC downregulated or overexpressed stable cell lines and their control cell lines. Utilized the LC3-GFP-mRFP fluorescence dual-labeling lentivirus system and laser confocal microscopy to examine autophagic flux. 5)Treated TESC downregulated cells with the autophagy inhibitor 3-MA. Conducted WB to assess the expression levels of autophagy-related proteins and plotted drug sensitivity curves using IC50 experiments to evaluate the impact of 3-MA on reversing liver cancer cell sensitivity to lenvatinib. Results: Compared to the control group, HCC cells overexpressing TESC showed an increased IC50 value and reduced sensitivity to lenvatinib, while TESC downregulation resulted in a decreased IC50 value and decreased sensitivity to lenvatinib. Subcutaneous tumor experiments in nude mice indicated that, compared to the control group, tumors with reduced TESC expression were more sensitive to lenvatinib. Additionally, in HCC cells overexpressing TESC, protein expression levels of LC3B II/I and Beclin1 significantly decreased, while P62 expression increased. Conversely, TESC downregulation significantly increased protein expression levels of LC3B II/I and Beclin1, while P62 expression decreased. Furthermore, results from the LC3-GFP-mRFP autophagy dual-labeling lentivirus system showed a significant reduction in fluorescence spots in the TESC overexpression group compared to the control group, indicating weakened autophagic flux. Treatment of TESC downregulated liver cancer cells with 3-MA resulted in an increased IC50 value compared to the control group. Conclusion: TESC expression levels are associated with the sensitivity of liver cancer cells to lenvatinib, possibly by inhibiting autophagy and affecting the sensitivity of liver cancer cells to lenvatinib. Citation Format: Hao Zhuang, Tingting Zhang, Jiaqi Chen. TESC mediates resistance to lenvatinib in hepatocellular carcinoma by regulating cell autophagy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5866.

The Temporal and Spatial Changes of Autophagy and PI3K Isoforms in Different Neural Cells After Hypoxia/Reoxygenation Injury.

There are limited therapeutic options for patient with traumatic spinal cord injury (SCI). Phosphoinositide 3-kinase family (PI3Ks) are the key molecules for regulating cell autophagy, which is a possible way of treating SCI. As we know, PI3K family are composed of eight isoforms, which are distributed into three classes. While the role of PI3Ks in regulating autophagy is controversial and the effects may be in a cell-specific manner. Different isoforms do not distribute in neural cells consistently and it is not clear how the PI3K isoforms regulate and interact with autophagy. Therefore, we explored the distributions and expression of different PI3K isoforms in two key neural cells (PC12 cells and astrocytes). The results showed that the expression of LC3II/I and p62, which are the markers of autophagy, changed in different patterns in PC12 cells and astrocytes after hypoxia/reoxygenation injury (H/R). Furthermore, the mRNA level of eight PI3K isoforms did not change in the same way, and even for the same isoform the mRNA activities are different between PC12 cells and astrocytes. What is more, the results of western blot of PI3K isoforms after H/R were inconsistent with the relevant mRNA. Based on this study, the therapeutic effects of regulating autophagy on SCI are not confirmed definitely, and its molecular mechanisms may be related with different temporal and spatial patterns of activation and distributions of PI3K isoforms.

RNA-binding domain 2 of nucleolin is important for the autophagy induction of curcumol in nasopharyngeal carcinoma cells

Background & AimsExcessive autophagy induces cell death and is regarded as the treatment of cancer therapy. We have confirmed that the anti-cancer mechanism of curcumol is related to autophagy induction. As the main target protein of curcumol, RNA binding protein nucleolin (NCL) interacted with many tumor promoters accelerating tumor progression. However, the role of NCL in cancer autophagy and in curcumol's anti-tumor effects haven't elucidated. The purpose of the study is to identify the role of NCL in nasopharyngeal carcinoma autophagy and reveal the immanent mechanisms of NCL played in cell autophagy. Methods & ResultsIn the current study, we have found that NCL was markedly upregulated in nasopharyngeal carcinoma (NPC) cells. NCL overexpression effectively attenuated the level of autophagy in NPC cells, and NCL silence or curcumol treatment obviously aggravated the autophagy of NPC cells. Moreover, the attenuation of NCL by curcumol lead a significant suppression on PI3K/AKT/mTOR signaling pathway in NPC cells. Mechanistically, NCL was found to be directly interact with AKT and accelerate AKT phosphorylation, which caused the activation of the PI3K/AKT/mTOR pathway. Meanwhile, the RNA Binding Domain (RBD) 2 of NCL interacts with Akt, which was also influenced by curcumol. Notably, the RBDs of NCL delivered AKT expression was related with cell autophagy in the NPC. ConclusionThe results demonstrated that NCL regulated cell autophagy was related with interaction of NCL and Akt in NPC cells. The expression of NCL play an important role in autophagy induction and further found that was associated with its effect on NCL RNA-binding domain 2. This study may provide a new perspective on the target protein studies for natural medicines and confirm the effect of curcumol not only regulating the expression of its target protein, but also influencing the function domain of its target protein.

Non-coding RNAs: The recently accentuated molecules in the regulation of cell autophagy for ovarian cancer pathogenesis and therapeutic response.

Autophagy is a self-recycling and conserved process, in which the senescent cytoplasmic components are degraded in cells and then recycled to maintain homeostatic balance. Emerging evidence has suggested the involvement of autophagy in oncogenesis and progression of various cancers, such as ovarian cancer (OC). Meanwhile, the non-coding RNAs (ncRNAs) frequently regulate the mRNA transcription and other functional signaling pathways in cell autophagy, displaying promising roles in human cancer pathogenesis and therapeutic response. This article mainly reviews the cutting-edge research advances about the interactions between ncRNAs and autophagy in OC. This review not only summarizes the underlying mechanisms of dynamic ncRNA-autophagy association in OC, but also discusses their prognostic implications and therapeutic biomarkers. The aim of this review was to provide a more in-depth knowledge framework exploring the ncRNA-autophagy crosstalk and highlight the promising treatment strategies for OC patients.

New Visions on Natural Products and Cancer Therapy: Autophagy and Related Regulatory Pathways.

Macroautophagy (autophagy) has been a highly conserved process throughout evolution and allows cells to degrade aggregated/misfolded proteins, dysfunctional or superfluous organelles and damaged macromolecules, in order to recycle them for biosynthetic and/or energetic purposes to preserve cellular homeostasis and health. Changes in autophagy are indeed correlated with several pathological disorders such as neurodegenerative and cardiovascular diseases, infections, cancer and inflammatory diseases. Conversely, autophagy controls both apoptosis and the unfolded protein response (UPR) in the cells. Therefore, any changes in the autophagy pathway will affect both the UPR and apoptosis. Recent evidence has shown that several natural products can modulate (induce or inhibit) the autophagy pathway. Natural products may target different regulatory components of the autophagy pathway, including specific kinases or phosphatases. In this review, we evaluated ~100 natural compounds and plant species and their impact on different types of cancers via the autophagy pathway. We also discuss the impact of these compounds on the UPR and apoptosis via the autophagy pathway. A multitude of preclinical findings have shown the function of botanicals in regulating cell autophagy and its potential impact on cancer therapy; however, the number of related clinical trials to date remains low. In this regard, further pre-clinical and clinical studies are warranted to better clarify the utility of natural compounds and their modulatory effects on autophagy, as fine-tuning of autophagy could be translated into therapeutic applications for several cancers.

Advance of Mesenchymal Stem Cells in Chronic End-Stage Liver Disease Control.

The chronic liver diseases will slowly develop into liver fibrosis, cirrhosis, and even liver cancer if no proper control is performed with high efficiency. Up to now, the most effective treatment for end-stage liver diseases is liver transplantation. However, liver transplantation has the problems of donor deficiency, low matching rate, surgical complications, high cost, and immune rejection. These problems indicate that novel therapeutic strategies are urgently required. Mesenchymal stem cells (MSCs) are somatic stem cells with multidirectional differentiation potential and self-renewal ability. MSCs can secrete a large number of cytokines, chemokines, immunomodulatory molecules, and hepatotrophic factors, as well as produce extracellular vesicles. They alleviate liver diseases by differentiating to hepatocyte-like cells, immunomodulation, homing to the injured site, regulating cell ferroptosis, regulating cell autophagy, paracrine effects, and MSC-mitochondrial transfer. In this review, we focus on the main resources of MSCs, underlying therapeutic mechanisms, clinical applications, and efforts made to improve MSC-based cell therapy efficiency.

Spermidine activates authophagy but does not rescue human neuroblastoma SH-SY5Y cells from effects of arginine starvation

Background. Neuroblastoma is a malignant tumor of the sympathetic nervous system common in early childhood. Autophagy is manifested in neuroblastoma cells at basal levels, but is often upregulated in cells of the aggressive neuroblastoma forms. The aim of the study was to evaluate effects of polyamine spermidine and deficiency of arginine on cell viability and autophagy regulation in cells of human neuroblastoma. Materials and Methods. The human neuroblastoma SH-SY5Y cell line was an experimental model for the MTT assay of metabolic activity and cell viability upon exposure to different concentrations of spermidine in complete and arginine-free media. Assessing autophagy induction under arginine deficiency and spermidine treatment was carried out using fluorescence microscopy of neuroblastoma cells labeled with autophagic lysosomes-staining dye monodancylcadaverine. Results and Discussion. It was found that arginine withdrawal abrogates proliferation of SH-SY5Y cells. In the presence of arginine precursor, citrulline, in arginine-free medium, SH-SY5Y cells could not proliferate and, therefore, are auxotrophic for arginine. SH-SY5Y cells were more sensitive to arginine starvation than to starvation for indispensible amino acids lysine or leucine. It was also revealed that spermidine at low concentrations of 5-10 μM did not affect SH-SY5Y cells viability irrespective of arginine availability. However, at 50 and higher concentrations this polyamine was highly cytotoxic in arginine-sufficient or deficient media. Analysis of autophagy induction by spermidine and under arginine starvation revealed an increase in the number of autophagic lysosomes in SH-SY5Y cells and additive effect of the two stimuli. Conclusion. The described experiments revealed that arginine deprivation abrogated proliferation, led to a decrease in cell viability and induced autophagy in human neuroblastoma SH-SY5Y cells. Spermidine at the concentrations of 5-10 μM, while upinducing autophagy, did not improve survival of SH-SY5Y cells under arginine deprivation, whereas at a concentration above 50 μM spermidine had a strong cytotoxic effect. The main observation of this study is that autophagy can be readily manipulated in neuroblastoma cells by simultaneous deprivation for arginine and spermidine treatment.

Network pharmacology and molecular docking study on the effect of Kaempferol in treatment of metabolic associated fatty liver disease.

To study therapeutic effect of kaempferol on metabolic associated fatty liver disease (MAFLD) by network pharmacology and molecular docking combined with cell experiments. First, use the SwissTargetPrediction database to predict the targets of kaempferol, and collect the targets of MAFLD through the Disgenet database and the GeneCards database. Then, the common target of kaempferol and MAFLD was enriched and analyzed by the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes, and the protein-protein interaction (PPI) network was constructed through the string database to obtain the key targets, and carry out molecular docking of key targets with kaempferol; In cell experiment, oleic acid induced steatosis in HepG2 cells, which was intervened by kaempferol, the level of triglyceride (TG) was detected, the lipid deposition was observed by oil red O staining, and the protein expression was detected by Western blot. The results showed that there are 33 common targets for kaempferol and MAFLD. The biological process of GO is related to the regulation of protein kinase B, cell apoptosis, inflammatory factors, lipoxygenase, etc. Its action pathway is related to the phosphatidylinositol-3-kinase and protein kinase B (PI3K-AKT) signaling pathway, hypoxia-inducible factor 1 signaling pathway, forkhead box protein O signaling pathway, AMP-activated protein kinase signaling pathway, tumor necrosis factor signaling pathway, etc., the key targets are protein kinase B (AKT1), pros-taglandin G/H synthase 2, matrix metalloproteinase-9, epidermal growth factor receptor, and the molecular docking of kaempferol with the four key targets shows good binding properties. Cell experiments show that kaempferol can reduce cell TG levels, reduce lipid deposition, increase the expression of PI3K, AKT, and beclin-1, and reduce the expression of caspase-3 and nuclear factor-kappa B. Kaempferol can treat MAFLD by regulating the PI3K-AKT signaling pathway to regulate cell autophagy, apoptosis, and inflammation. This study shows that kaempferol can regulate lipid metabolism, reduce apoptosis, regulate inflammation and autophagy in the fatty liver cell model. It reveals the therapeutic mechanism of kaempferol on MAFLD and provides a natural product candidate for the treatment of MAFLD.

Norkurarinone and isoxanthohumol inhibit high glucose and hypoxia-induced angiogenesis via improving oxidative stress and regulating autophagy in human retinal microvascular endothelial cells

Diabetic retinopathy (DR) is one of the most serious complications of diabetic microangiopathy. Recent studies have shown its close association with high glucose-induced oxidative stress and autophagy disorder. Previous studies showed that various compounds of flavonoids of Sophora flavescens Aiton extracted using ethyl acetate (SFE) could cross the blood-retinal barrier, exerting favorable effects on retinal tissue disorders and angiogenesis in rats with DR. However, the mechanism and the specific material basis for SFE are still unclear. Here, we established the in vitro DR model of human retinal microvascular endothelial cell (HRMECs) induced by high glucose and hypoxia (HGY), screened out the potential pharmacodynamic components of SFE viz. norkurarinone (NKR) and isoxanthohumol (IXM), and proved that they could improve the pathological features of angiogenesis. Further, we explored the mechanism of action of NKR and IXM, investigating their effects on cellular oxidative stress and autophagy levels under HGY conditions. Finally, the role of the PI3K/AKT/mTOR signaling pathway in the regulation of cell autophagy by NKR and IXM was evaluated. Collectively, NKR and IXM could improve cellular oxidative stress state and activate PI3K/AKT/mTOR signaling pathway to regulate autophagy dysregulation, thus playing a significant role in protecting HRMECs from HGY-caused angiogenesis.

The Mechanisms of Luteolin in Treating COVID-19 Based on Bioinformatics Analysis and Molecular Docking

Abstract Luteolin is a natural flavonoid that has a variety of pharmacological activities, such as anti-inflammatory, anti-allergic, anti-bacterial, anti-viral, apoptosis inhibition, cell autophagy regulation, and anti-tumor activity. It is one of the main ingredients of an expert-recommended herbal formula for the prevention and treatment of coronavirus disease 2019 (COVID-19). This suggests that luteolin has strong pharmacological effects on the prevention and treatment of COVID-19. The aims of this study were to identify the molecular targets of luteolin and to infer the possible mechanisms by which it exerts its pharmacological effects. The GSE159787 data set was obtained from the Gene Expression Omnibus online database, and differentially expressed genes were analyzed. There were 22 upregulated differentially expressed genes enriched in the COVID-19 signaling pathway, suggesting that the upregulation of these genes may be closely related to the occurrence of COVID-19. Molecular docking results showed that luteolin had strong binding efficiency to 20 of these 22 key genes. Six of these genes (CFB, EIF2AK2, OAS1, MAPK11, OAS3, and STAT1) showed strong binding activity. Luteolin can regulate the COVID-19 signaling pathway by combining with these targets, which may have a therapeutic effect on COVID-19.

Extracellular Vesicles from BMSCs Prevent Glucocorticoid-Induced BMECs Injury by Regulating Autophagy via the PI3K/Akt/mTOR Pathway.

Osteonecrosis of the femoral head (ONFH) is a common clinical disease with a high disability rate. Injury of bone microvascular endothelial cells (BMECs) caused by glucocorticoid administration is one of the important causes of ONFH, and there is currently a lack of effective clinical treatments. Extracellular vesicles derived from bone stem cells (BMSC-EVs) can prevent ONFH by promoting angiogenesis and can inhibit cell apoptosis by regulating autophagy via the PI3K/Akt/mTOR signaling pathway. The present study aimed to investigate the effect of extracellular vesicles derived from bone marrow stem cells (BMSC) on a glucocorticoid-induced injury of BMECs and possible mechanisms. We found that BMSC-EVs attenuated glucocorticoid-induced viability, angiogenesis capacity injury, and the apoptosis of BMECs. BMSC-EVs increased the LC3 level, but decreased p62 (an autophagy protein receptor) expression, suggesting that BMSC-Exos activated autophagy in glucocorticoid-treated BMECs. The protective effects of BMSC-EVs on the glucocorticoid-induced injury of BMECs was mimicked by a known stimulator of autophagy (rapamycin) and could be enhanced by co-treatment with an autophagy inhibitor (LY294002). BMSC-EVs also suppressed the PI3K/Akt/mTOR signaling pathway, which regulates cell autophagy, in glucocorticoid-treated BMECs. In conclusion, the results indicate that BMSC-EVs prevent the glucocorticoid-induced injury of BMECs by regulating autophagy via the PI3K/Akt/mTOR pathway.

Therapeutic targets and mechanism of hydroxysafflower yellow A on poststroke cognitive impairment: Network pharmacology, molecular docking and molecular dynamics simulation

ObjectiveThe aim of this study was to explore the therapeutic target and mechanism of Hydroxy Safflower Yellow A pigment (HSYA)—the main water-soluble component of Safflower—in the treatment of Poststroke Cognitive Impairment (PSCI) by network pharmacology and molecular docking methods. MethodGeneCards, PharmMapper, and Swiss Target Prediction databases were used to screen HSYA targets. Protein-Protein Interaction analysis, Gene Ontology, and KEGG enrichment analysis were performed through STRING and Metascape databases, respectively. Cytoscape 3.6.0 was used to draw the network diagram of the “HSYA-target-PSCI pathway.” AutoDockVina was used for molecular docking. ResultsA total of 310 targets of HSYA and 2455 potential targets of PSCI were screened, and the shared target was 159. After GO and KEGG enrichment analysis, HSYA was found to exhibit a therapeutic effect on PSCI by regulating various cancer pathways, endocrine regulation, cell proliferation, and apoptosis pathways. The molecular docking results suggest that HSYA has the best docking activity with the core target HRAS. Molecular dynamics simulation results showed that HSYA was the best binding agent to MAPK1, followed by HRAS. ConclusionHSYA may regulate cell autophagy and apoptosis by regulating various pathways like PI3K-AKT and MAPK signaling pathways. It inhibits the secretion of inflammatory and angiogenic factors, inhibits endothelial angiogenesis, and plays a role in treating PSCI.

SIRT2 Affects Cell Proliferation and Apoptosis by Suppressing the Level of Autophagy in Renal Podocytes

Purpose Despite the discovery of many important molecules in diabetic nephropathy, there has been very limited progress in the management of diabetic kidney diseases and the design of new drugs. To fill this gap, the present study explored the expression of SIRT2 in high-glucose murine kidney foot cells and its impact on cell biological functions. Methods Expression levels of SIRT2 in the MPC-5 of murine kidney foot cells after high and normal glucose treatment or in cells targeted with siRNA were detected using qRT-PCR. Cellular proliferation and programmed cell death were analyzed via the CCK8 assay and flow cell technique, separately. Levels of autophagy markers were measured by western blotting, and chloroquine treatment was applied to the cells to observe the effect of SIRT2 on cell proliferation and apoptosis after treatment. Results The expression level of SIRT2 was remarkably upregulated in the high-GLU group in contrast to the low-GLU group. The cell proliferation and autophagy levels were significantly reduced, and apoptosis was remarkably reinforced in the high-GLU group in contrast to the normal GLU group. However, knocking down the expression level of SIRT2 caused an increase in cell proliferation and cell autophagy levels and significantly weakened apoptosis. Chloroquine influenced cell proliferation and apoptosis in cells targeted with SIRT2 siRNA. Conclusion SIRT2 expression was upregulated in hyperglycaemic murine kidney foot cells, and knocking down the expression level of SIRT2 affected the biological function of the cells. We found that SIRT2 may modulate cell proliferation and apoptosis by regulating cell autophagy.

Protective effect of polysaccharides from Ostrea rivularis against reproductive injury via regulating autophagy induced by oxidative stress

The objective of this study was to investigate the effect of polysaccharides from Ostrea rivularis (ORP) relieving reproductive damage by regulating autophagy. The results showed that ORP intervention could alleviate the pathological changes of the testis and alleviate oxidative stress which were caused by cyclophosphamide (CTX) in vivo, including improve sperm symptoms and rise testosterone level. Reduced level of autophagy after ORP intervention was observed by transmission electron microscopy (TEM), which implied that ORP might regulate cell autophagy. In vitro experiments showed that ORP could alleviate the damage of TM4 cells induced by H2O2, reduce the level of intracellular ROS and the content of MDA. Autophagy-related protein expressions of p62, LC3, Beclin-1 before and after 3-MA inhibitor intervention were also proved that ORP could regulate autophagy. Overall, these results confirmed that ORP could reduce reproductive damage related to autophagy.

Exosome-Derived From Sepsis Patients' Blood Promoted Pyroptosis of Cardiomyocytes by Regulating miR-885-5p/HMBOX1.

BackgroundSeptic myocardial depression has been associated with increased morbidity and mortality. miR-885-5p has been shown to regulate cell growth, senescence, and/or apoptosis. Published studies demonstrated that Homeobox-containing protein 1 (HMBOX1) inhibits inflammatory response, regulates cell autophagy, and apoptosis. However, the role of miR-885-5p/HMBOX1 in sepsis and septic myocardial depression and the underlying mechanism is not fully understood.Materials and MethodsExosomes (exos) derived from sepsis patients (sepsis-exos) were isolated using ultracentrifugation. Rats were subjected to cecal ligation and puncture surgery and treated with sepsis-exos. HMBOX1 was knocked down or overexpressed in AC16 cells using lentiviral plasmids carrying short interfering RNAs targeting human HMBOX1 or carrying HMBOX1 cDNA. Cell pyroptosis was measured by flow cytometry. The secretion of IL-1β and IL-18 was examined by ELISA kits. Quantitative polymerase chain reaction (PCR) or western blot was used for gene expression.ResultsSepsis-exos increased the level of miR-885-5p, decreased HMBOX1, elevated IL-1β and IL-18, and promoted pyroptosis in AC16 cells. Septic rats treated with sepsis-exos increased the serum inflammatory cytokines is associated with increased pyroptosis-related proteins of hearts. MiR-885-5p bound to the three prime untranslated regions of HMBOX1 to negatively regulate its expression. Overexpressing HMBOX1 reversed miR-885-5p-induced elevation of inflammatory cytokines and upregulation of NLRP3, caspase-1, and GSDMD-N in AC16 cells. The mechanistic study indicated that the effect of HMBOX1 was NF-κB dependent.ConclusionSepsis-exos promoted the pyroptosis of AC16 cells through miR-885-5p via HMBOX1. The results show the significance of the miR-885-5p/HMBOX1 axis in myocardial cell pyroptosis and provide new directions for the treatment of septic myocardial depression.

MiR-133a targets YES1 to reduce cisplatin resistance in ovarian cancer by regulating cell autophagy

BackgroundAccumulating evidence has revealed that aberrant microRNA (miRNA) expression can affect the development of chemotherapy drug resistance by modulating the expression of relevant target proteins. Emerging evidence has demonstrated that miR-133a participates in the tumorigenesis of various cancers. However, whether miR-133a is associated with cisplatin resistance in ovarian cancer remains unclear.ObjectiveTo investigate the role of miR-133a in the development of cisplatin resistance in ovarian cancer.MethodsMiR-133a expression in cisplatin-resistant ovarian cancer cell lines was assessed by reverse-transcription quantitative PCR (RT–qPCR). A cell counting kit-8 (CCK-8) assay was used to evaluate the viability of tumour cells treated with cisplatin in the presence or absence of miR-133a. A luciferase reporter assay was used to analyse the binding of miR-133a with the 3′ untranslated region (3′UTR) of YES proto-oncogene 1 (YES1). The YES1 expression level was analysed using a dataset from the International Cancer Genome Consortium (ICGC) and assessed by RT–qPCR and western blotting in vitro. The roles and mechanisms of YES1 in cell functions were further probed via gain- and loss-of-function analysis.ResultsThe expression of miR-133a was significantly decreased in cisplatin-resistant ovarian cancer cell lines (A2780-DDP and SKOV3-DDP), and the overexpression of the miR-133a mimic reduced cisplatin resistance in A2780-DDP and SKOV3-DDP cells. Treatment with the miR-133a inhibitor increased cisplatin sensitivity in normal A2780 and SKOV3 cells. MiR-133a binds the 3’UTR of YES1 and downregulates its expression. Bioinformatics analysis revealed that YES1 expression was upregulated in recurrent cisplatin-resistant ovarian cancer tissue, and in vitro experiments also verified its upregulation in cisplatin-resistant cell lines. Furthermore, we discovered that miR-133a downregulated the expression of YES1 and thus inhibited cell autophagy to reduce cisplatin resistance. Yes1 knockdown significantly suppressed the cisplatin resistance of ovarian cancer cells by inhibiting autophagy in vitro. Xenograft tumour implantation further demonstrated that Yes1 overexpression promoted ovarian tumour development and cisplatin resistance.ConclusionsOur results suggest that the miR-133a/YES1 axis plays a critical role in cisplatin resistance in human ovarian cancer by regulating cell autophagy, which might serve as a promising therapeutic target for ovarian cancer chemotherapy treatment in the future.