Autophagy-related Genes Beclin-1 Research Articles

Invasion of human dental pulp fibroblasts by Porphyromonas gingivalis leads to autophagy via the phosphoinositide 3-kinase/Akt/mammalian target of rapamycin signaling pathway

ObjectivesPorphyromonas gingivalis is a pathogenic bacterium that causes periodontitis and dental pulp infection. Autophagy is a potential mechanism involved in inflammatory disease. This study established an in vitro model of P. gingivalis intracellular infection in human dental pulp fibroblasts (HDPFs) to investigate the effects of live P. gingivalis on HDPFs. MethodsMorphological and quantification techniques such as fluorescence microscopy, transmission electron microscopy (TEM), indirect immunofluorescence analysis, enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (PCR), and western blotting were used in this study. ResultsAfter cell invasion, P. gingivalis is mainly localized in the cytoplasm and lysosomes. Additionally, P. gingivalis activates autophagy in HDPFs by upregulating the expression of autophagy-related gene Beclin-1, activate autophagy-related gene12 (ATG12), and microtubule-associated protein light chain 3 (LC3). Furthermore, the invasion of P. gingivalis leads to increased phosphorylation of PI3K, Akt, and mTOR with the addition of rapamycin, whereas the addition of wortmannin decreased phosphorylation. This invasion of P. gingivalis, also causes an inflammatory response, leading to the upregulation of IL-1β, IL-6, and TNF-α. Rapamycin helps decrease levels of pro-inflammatory cytokines, but the addition of wortmannin increases them. These results show that the invasion of P. gingivalis can cause excessive inflammation and promote the autophagy of HDPFs, which is regulated by PI3K/Akt/mTOR. ConclusionsP. gingivalis escapes the immune system by inducing autophagy in the host cells, causing excessive inflammation. P. gingivalis regulates autophagy in HDPFs through the phosphoinositide 3-kinase/Akt/mammalian target of rapamycin pathway.

Exploring the novel benefits of leucine: Protecting nitrite-induced liver damage in sub-adult grass carp (Ctenopharyngodon idella) through regulating mitochondria quality control

Leucine is an essential amino acid for fish. The ability of leucine to resist stress in fish has not been reported. Nitrite is a common pollutant in the aquatic environment. Therefore, we investigated the effects of dietary leucine on growth performance and nitrite-induced liver damage, mitochondrial dysfunction, autophagy, and apoptosis for sub-adult grass carp. A total of 450 grass carp (615.91 ± 1.15 g) were selected and randomly placed into 18 net cages. The leucine contents of the six diets were 2.91, 5.90, 8.92, 11.91, 14.93, and 17.92 g/kg, respectively. After a 9-week feeding trial, the nitrite exposure experiment was set up for 96 h. These results indicated that dietary leucine significantly promoted FW, WG, PWG, and SGR of sub-adult grass carp (P < 0.05). Appropriate levels of dietary leucine (11.91–17.92 g/kg) decreased the activities of serum parameters (glucose, cortisol, and methemoglobin contents, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and lactate dehydrogenase), the contents of reactive oxygen species (ROS), nitric oxide (NO) and peroxynitrite (ONOO−). In addition, appropriate levels of dietary leucine (11.91–17.92 g/kg) increased the mRNA levels of mitochondrial biogenesis genes (PGC-1α, Nrf1/2, TFAM), fusion-related genes (Opa1, Mfn1/2) (P < 0.05), and decreased the mRNA levels of caspase 3, caspase 8, caspase 9, fission-related gene (Drp1), mitophagy-related genes (Pink1, Parkin) and autophagy-related genes (Beclin1, Ulk1, Atg5, Atg7, Atg12) (P < 0.05). Appropriate levels of dietary leucine (8.92–17.92 g/kg) also increased the protein levels of AMP-activated protein kinase (AMPK), prostacyclin (p62) and decreased the protein levels of protein light chain 3 (LC3), E3 ubiquitin ligase (Parkin), and Cytochrome c (Cytc). Appropriate levels of leucine (8.92–17.92 g/kg) could promote growth performance and alleviate nitrite-induced mitochondrial dysfunction, autophagy, apoptosis for sub-adult grass carp. Based on quadratic regression analysis of PWG and serum GPT activity, dietary leucine requirements of sub-adult grass carp were recommended to be 12.47 g/kg diet and 12.55 g/kg diet, respectively.

The potential anticancer effect of bee venom in combination with sorafenib against HepG2 cell lines via induction of apoptosis and autophagy candidate genes

Abstract Background Hepatocellular carcinoma (HCC) is a severe threat and a main reason for cancer-related deaths around the world. Drug resistance to sorafenib (Sorf), the effective HCC first-line therapy, is very common. A number of natural compounds, notably bee venom (BV), have been claimed to show a great impact against cancer when administered on its own or in conjunction with chemotherapy. Thus, this study aimed to investigate the anticancer effect of BV alone and/or combined with Sorf on HepG2 liver cancer cell lines. Methods Both mRNA and protein expressions of Bax, Bcl-2 and Beclin-1 were investigated by quantitative real-time PCR (qPCR) and western blot respectively, to examine the apoptotic and autophagic regulatory effects of BV and Sorf single treatments plus BV/Sorf combination on HepG2 cell lines. Results Our findings showed that BV and Sorf had considerable dose-dependent anti-proliferative effects on HepG2 cells whether administered alone or in combination, with the greatest impact for the combined therapies. Single BV and Sorf treatments showed IC50 of 93.21 and 7.28 μg/ml respectively, while combined treatment showed IC50 of 6.73 μg/ml BV + 6.73 μg/ml Sorf. Moreover, both the pro-apoptotic gene Bax and the autophagy-related gene Beclin-1 showed significant up-regulation in their mRNA expression, while the anti-apoptotic Bcl-2 mRNA gene expression showed significant down-regulation after BV/Sorf treatment as compared to either BV or Sorf single treatment. These qPCR results were further confirmed by western blot. Conclusions These findings indicate that BV synergistically potentiates the anticancer effect of Sorf on HepG2 cells through induction of apoptotic and autophagic machineries.

Clinical Significance of HMGB1 and Autophagy-Related Genes in Sinonasal Inverted Papilloma.

Sinonasal inverted papilloma (SNIP) is a noncancerous tumor that develops in the mucous membrane of the nasal sinuses. Many malignancies are tightly linked to autophagy, an intracellular self-degradation mechanism. HMGB1 has demonstrated its ability to modulate autophagy in many pathological conditions. This work investigates how HMGB1 and other genes involved in autophagy contribute to SNIP. The study included 45 patients with SNIP and a control group consisting of 28 individuals. In each group, qPCR was employed to examine the mRNA expression levels of genes correlated with autophagy and HMGB1. HMGB1 and genes associated with autophagy were examined for protein expression levels via Western Blot and immunohistochemical staining assays. At the same time, the association between HMGB1 and genes involved in autophagy was discovered through correlation analysis. Furthermore, Krouse staging was utilized for investigating the expression levels of HMGB1 and other autophagy-related genes at various stages in clinically staged SNIP patients. LC3B, ATG5, and Beclin1 autophagy-related genes and HMGB1 were substantially expressed in SNIP. Additionally, there was a positive correlation between HMGB1 and these genes. During various phases of SNIP, the levels of HMGB1 expression and autophagy-related genes were notably elevated at stage T4 compared with stage T2. Clinical staging in SNIP is correlated with HMGB1 expression in conjunction with autophagy-related genes LC3B, ATG5, and Beclin1, suggesting the possibility of novel prognostic indicators. NA Laryngoscope, 134:3941-3946, 2024.

Arabidopsis BECLIN1-induced autophagy mediates reprogramming in tapetal programmed cell death by altering the gross cellular homeostasis

In flowering plants, the tapetum degeneration in post-meiotic anther occurs through developmental programmed cell death (dPCD), which is one of the most critical and sensitive steps for the proper development of male gametophytes and fertility. Yet the pathways of dPCD, its regulation, and its interaction with autophagy remain elusive. Here, we report that high-level expression of Arabidopsis autophagy-related gene BECLIN1 (BECN1 or AtATG6) in the tobacco tapetum prior to their dPCD resulted in developmental defects. BECN1 induces severe autophagy and multiple cytoplasm-to-vacuole pathways, which alters tapetal cell reactive oxygen species (ROS)-homeostasis that represses the tapetal dPCD. The transcriptome analysis reveals that BECN1- expression caused major changes in the pathway, resulting in altered cellular homeostasis in the tapetal cell. Moreover, BECN1-mediated autophagy reprograms the execution of tapetal PCD by altering the expression of the key developmental PCD marker genes: SCPL48, CEP1, DMP4, BFN1, MC9, EXI1, and Bcl-2 member BAG5, and BAG6. This study demonstrates that BECN1-mediated autophagy is inhibitory to the dPCD of the tapetum, but the severity of autophagy leads to autophagic death in the later stages. The delayed and altered mode of tapetal degeneration resulted in male sterility.

The autophagy-related genes Beclin1 and LC3 in the prognosis of pancreatic cancer [Retraction

The autophagy-related genes Beclin1 and LC3 in the prognosis of pancreatic cancer [Retraction

The role of the Beclin-1: a gene related to autophagy in rheumatoid arthritis

BackgroundRheumatoid arthritis (RA) is a chronic autoimmune disorder. Autophagy, a regulator of cell homeostasis, can impact innate and adaptive immune cells activation and contribute to the pathogenesis of RA. The purpose of this study was to assess the significance of autophagy in RA, by investigating the autophagy signaling Beclin-1 in RA patients.ResultsIn RA patients, the Beclin-1 gene expression level was higher than the healthy controls with a statistically highly significant difference (P < 0. 001) where the gene expression mean was 3.33 ± 0.45 in patients and 0.98 ± 0.070 in controls. There was a significant positive correlation between Beclin-1 gene expression and disease duration (p = 0.013*), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and rheumatoid factor (RF) titer (P = 0.018*, 0.027*, and 0.023* respectively). Beclin-1 gene overexpression is significantly correlated with disease activity parameters (DAS 28, patient and physician global health assessment). Furthermore, the Beclin-1 gene overexpression is highly correlated with the disability index, Modified Health Assessment Questionnaire (MHAQ) (P < 0.001).ConclusionThe elevated autophagy-related gene Beclin-1 expression in RA patients can contribute to RA probability, high disease activity, and severity. Therefore, suppressing autophagy may be a therapeutic target for RA.

Regulation of epidermal growth factor receptor tyrosine kinase inhibitor resistance via Ambra1-mediated autophagy in non-small cell lung cancer.

To explore the molecular mechanisms related to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) resistance, along with potential therapeutic targets and strategies. The autophagy and Beclin 1 regulator 1 (Ambra1) short hairpin ribonucleic acid (shRNA) lentivirus vector and Ambra1 overexpression plasmid, constructed with a plasmid cloning deoxyribonucleic acid (pcDNA) 3.1 vector, were used to down-regulate and up-regulate Ambra1 expression in the human lung adenocarcinoma erlotinib-resistant cell line (PC9/ER), respectively, as well as to screen stable transgenic cell lines. The IC50 of Erlotinib in these cell lines were measured to determine their resistance status. The real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to measure messenger ribonucleic acid (mRNA) expression of resistance-related genes like multidrug resistance protein 1 (MDR1), multidrug resistance-associated protein 1 (MRP1), and lung drug-resistant-related protein (LRP). Western blot was performed to analyze the protein expressions of the autophagy-related genes Beclin 1, LC3II/I, and p62. Each stable transgenic line formed a tumor under the skin in nude mice; the mice with subcutaneous tumorigenesis of PC9/ER cells and shAmbra1-PC9/ER cells were subsequently treated with rapamycin (RAPA) and chloroquine (CQ), respectively. The mRNA expressions of MDR1, MRP1, and LRP in each tumor tissue sample were detected by qRT-PCR. The protein expressions of adenosine monophosphate-activated protein kinase (AMPK), phosphorylated-AMPK (p-AMPK), forkhead box O3 (FoxO3a), and phosphorylated forkhead box O3 (p-FoxO3a) in the AMPK/FoxO3a signaling pathway were analyzed via Western blot. The qRT-PCR result revealed that the level of Ambra1 in EGFR-TKI-resistant cells had increased. This was further exacerbated by the overexpression of Ambra1 and was reduced after its inhibition. Additionally, Ambra1 upregulated the mRNA expression of drug-resistant genes and the expression of autophagy-related proteins. Subcutaneous tumorigenesis of RAPA-treated shAmbra1-PC9/ER cells resulted in increased expression of drug resistance-related genes and a concomitant decrease in p-AMPK and increase in p-FoxO3a. The results revealed that Beclin-1/β-actin, p62/β-actin, and LC3II/I in the model group were all significantly increased compared to the control group, with P<0.05. Compared to the model group, Beclin-1/β-actin, p62/β-actin, and LC3II/I were all significantly higher in the pcDNA-Ambra1 group, with P<0.05. Compared to the model group, Beclin-1/β-actin, p62/β-actin, and LC3II/I were all significantly decreased in the shAmbra1 group, with P<0.05. Thus, these data suggest that Ambra1 promotes cellular autophagy. In addition, subcutaneous tumorigenesis of CQ-treated shAmbra1-PC9/ER cells resulted in reduced expression of drug resistance-related genes, and a concomitant increase in p-AMPK and decrease in p-FoxO3a. The results of this study revealed that Ambra1-mediated autophagy regulated EGFR-TKI resistance in NSCLC, most probably through the AMPK/FoxO3a signaling pathway.

Exposure to waterborne cadmium induce disorder of lipid metabolism, antioxidant system and autophagy in the muscle of crayfish Procambarus clarkii

Cadmium (Cd) is a non-essential toxic metal in the body, which can cause harmful effects on the aquatic environment and aquatic organisms. In this study, the effects of acute Cd exposure on lipid metabolism disorder, oxidative stress and autophagy in abdominal muscles of Procambarus clarkii were investigated, as well the underlying molecular mechanisms were explored. P. clarkii were exposed to 0 (control), 1 and 5 mg Cd/l, respectively, for 5 days. We found that TG content, fas, hsl, and cpt1 gene expression levels, as well as the Srebp1 protein content in abdominal muscle decreased with the Cd concentrations increased, indicating that acute Cd exposure induced disorder of lipid metabolism in the abdominal muscle of P. clarkii. Further studies showed that acute Cd exposure provoked oxidative stress in the abdominal muscle of P. clarkii by increasing the accumulation of malondialdehyde (MDA) in the abdominal muscle. The oxidative stress of abdominal muscle induced by acute Cd exposure may be due to the reduction of catalases (CAT) and glutathione peroxidase (GPX) enzyme activities and Nrf2 protein content in the nucleus. The expression levels of autophagy-related genes (beclin1, atg101, atg13, atg3, atg4b, atg5, atg7, lc3a, lc3c atg9a) were also affected by acute Cd exposure, suggesting that acute Cd exposure also affected autophagy activity in abdominal muscle of P. clarkii. Our research indicates that waterborne acute Cd exposure can induce lipid metabolism disorder, and oxidative stress, and inhibit the expression of genes that trigger autophagy in the abdominal muscle of P. clarkii. These results may be useful for understanding the mechanism of Cd muscular toxicity in crustaceans.

Methyltransferase 3 beta (DNMT3B) inhibition by decitabine promotes endometrial carcinoma cell apoptosis by autophagy induction

Autophagy regulates endometrial cancer cell apoptosis and inhibits endometrial cancer development; however, the specific underlying mechanisms are unclear. The effects of DNA methylation on endometrial cancer cell autophagy were explored in HEC-1B cells using decitabine, a DNA methylase inhibitor. Real-time fluorescence quantitative PCR (RT-qPCR) and western blot (WB) analyses were used to detect the mRNA and protein expression of DNA methylase (DNMT3B), autophagy-related genes LC3B and Beclin-1, and apoptosis-related genes Bax and Bcl-2. High-purity and high-quality RNA was obtained by nano-magnetic bead extraction, to ensure highly accurate RT-qPCR and WB results. MTT cell viability assay, scratch assay, and Transwell migration assay were utilized to detect the proliferation and migration of HEC-1B cells. The results showed that decitabine significantly inhibited the expression of DNMT3B protein and mRNA, with 25 μM decitabine being the most effective. In subsequent experiments, this concentration of decitabine was used. The low DNMT3B expression significantly inhibited the expression of Beclin-1 and LC3B proteins (***P &lt;0.001 and *P &lt;0.05) and mRNA (*P &lt;0.05 and *P &lt;0.05). Decitabine promoted the mRNA and protein expression of apoptotic factor Bax (*P &lt; 0.05 and *P &lt; 0.05), while inhibiting the mRNA protein expression of anti-apoptotic factor Bcl-2 (***P &lt;0.001 and *P &lt;0.05). MTT assay results showed decreased proliferation of HEC-1B cells following inhibition of DNMT3B expression by decitabine, which was significantly different from that of the NC group (*P &lt;0.05). The results of the cell scratch and Transwell migration assays showed reduced migration ability of HEC-1B cells compared to that observed in the NC group (**P &lt;0.01 and *P &lt;0.05). These results show that decitabine inhibits DNMT3B expression, and low DNMT3B levels regulate the expression of autophagy- and apoptosis-related factors, thereby inhibiting the proliferation and migration of endometrial cancer cells.

Superenhancers activate the autophagy-related genes Beclin1 and LC3B to drive metastasis and drug resistance in osteosarcoma.

Metastasis and drug resistance are the leading causes of poor prognosis in patients with osteosarcoma. Identifying the relevant factors that drive metastasis and drug resistance is the key to improving the therapeutic outcome of osteosarcoma. Here, we reported that autophagy was highly activated in metastatic osteosarcoma. We found increased autophagolysosomes in metastatic osteosarcoma cell lines by using electron microscopy, Western blot, and immunofluorescence experiments. We further examined the expression of the autophagy-related genes Beclin1 and LC3B in 82 patients through immunohistochemistry and found that Beclin1 and LC3B were highly related to unfavorable prognosis of osteosarcoma. Knockdown of Beclin1 and LC3B reduced invasion, metastasis, and proliferation in metastatic osteosarcoma cells. In vitro and in vivo studies also demonstrated that inhibiting by 3-MA inhibited cell growth and metastasis. Moreover, we demonstrated that autophagy-related genes were activated by SEs and that the inhibition of SEs by JQ-1 decreased the metastasis of osteosarcoma. Overall, our findings highlighted the association of autophagy with osteosarcoma progression and shed new light on autophagy-targeting therapy for osteosarcoma.

Yinhuang oral liquid protects acetaminophen-induced acute liver injury by regulating the activation of autophagy and Nrf2 signaling.

This study aimed to investigate the protective effect and potential mechanism of Yinhuang oral liquid (YOL) against acetaminophen (APAP) induced liver injury in mice. C57BL/6 mice were randomly divided into control group, model group (300mg/kg APAP), NAC group and YOL group. Mice were treated intragastrical with YOL (8g/kg) and N-Acetylcysteine (NAC, 300mg/kg) 6h before and 6h after the APAP (300mg/kg) intraperitoneal injection. 12h after APAP exposure, blood and liver samples were collected for subsequent testing. The results showed that APAP decreased liver index, induced liver pathological injury with hepatocytes swelling, necrosis and apoptosis and inflammatory cell infiltration. APAP exposure significantly increased serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels to 35 and 6 multiples than their original levels. YOL alleviated liver pathological damage, decreased the serum levels of ALT and AST in APAP exposure mice, and it worked better than NAC. Moreover, APAP promoted oxidative stress by increasing lipid peroxidation (MDA) and decreasing anti-oxidant enzyme activities of SOD and GSH, inhibited the mRNA levels of Nrf2, HO-1, Gclc and Gclm, and decreased the protein levels of Nrf2, HO-1 and Keap1, compared to control group. Furthermore, APAP exposure significantly down-regulated the mRNA and protein levels of autophagy related genes (Beclin-1, LC3-II, LC3-I, Atg4B, Atg5, Atg16L1 and Atg7). However, the gene levels of mTOR and p-mTOR increased, and p-ULK1 protein level decreased in liver of APAP treated mice. Additionally, YOL alleviated the oxidative injury by up-regulating Nrf2 pathway. The gene and protein levels of autophagy-related genes Beclin-1, LC3-II, LC3-I, Atg4B, Atg5, Atg16L1 and Atg7 reached the basal levels after YOL treatment. In conclusion, YOL had a protective and therapeutic role in APAP-induced liver injury in mice by activating Nrf2 signaling pathway and autophagy.

Endoplasmic reticulum stress-controlled autophagic pathway promotes polystyrene microplastics-induced myocardial dysplasia in birds

In complex ecosystems, birds are generally long-lived and occupy high trophic positions, making them good bioindicators for monitoring environmental contaminants. The effects of microplastics (MPs) on myocardial development in bird is currently unknown. Chicks, as a high trophic level terrestrial bird, may be more affected by MPs exposure and. Therefore, we established an in vivo model of chicks exposed to different concentrations of polystyrene microplastics (PS-MPs) and selected 12-day-old chicken embryos in vitro to extract primary cardiomyocytes to further investigate the potential molecular mechanisms of the effect of PS-MPs on myocardial development in birds. Histopathological observations revealed that the PS-MPs treated exhibited loose and irregular myocardial arrangement, large cell gaps and broken myocardial fiber bundles. More mechanistically, TnnT2, Nkx2-5, Gata4, TBX5 and ACTN2 were down-regulated, endoplasmic reticulum (ER) stress markers GRP78, PERK, eIF2α, IRE1, ATF4, ATF6 and CHOP were overexpressed, autophagy-related genes LC3, ATG5, Beclin1 and P62 were down-expressed after PS-MPs exposure, and the addition of 4PBA effectively deregulated the above aberrant expression. Hence, our report indicated that PS-MPs induced myocardial dysplasia in birds is mainly attributed to the ER stress-mediated autophagic pathway. This provided data supporting the protection of birds from the health risks of MPs pollution. More critically, the study of cardiac developmental toxicity in birds may help to better explain or solve the problem of MPs pollution in complex ecosystems.

Astaxanthin delays brain aging in senescence-accelerated mouse prone 10: inducing autophagy as a potential mechanism

ABSTRACT Brain aging is a complex biological process often associated with a decline in cognitive functions and motility. Astaxanthin (AST) is a strong antioxidant capable of crossing the blood–brain barrier. The effect of AST on brain aging and its physiological and molecular mechanism are still unclear. The study aimed to investigate whether AST from AstaReal A1010 improved brain aging by inducing autophagy in SAMP10 mice. Different concentrations of AstaReal A1010 were intragastrically administered to 6-month-old SAMP10 mice for 3 months. The results demonstrated that AST delayed age-related cognitive decline, motor ability and neurodegeneration, upregulated the expression levels of autophagy-related genes beclin-1 and LC3 in the brain. It may induce autophagy by regulating IGF-1/Akt/mTOR and IGF-1/Akt/FoxO3a signaling. Treatment with autophagy inhibitor 3-methyladenine (3MA) partly reversed the anti-aging effect of AST. In conclusion, our findings suggest that AST may induce autophagy by regulating IGF-1/Akt/mTOR and IGF-1/Akt/FoxO3a signaling, thereby delaying age-related neurodegeneration and cognitive decline in SAMP10 mice.

Shikonin, a promising therapeutic drug for osteoarthritis that acts via autophagy activation

Osteoarthritis (OA) is a chronic joint degenerative disease characterised by narrowed articular space, formation of surrounding osteophytes, and subchondral bone sclerosis. OA is caused by cartilage degeneration, which is closely correlated with the disequilibrium of anabolism and catabolism in chondrocytes. Previous studies have revealed that autophagy plays a significant role in maintaining the balance of anabolic and catabolic activities. Thus, targeting autophagy may be a promising therapeutic strategy for OA. Shikonin, a traditional Chinese herbal medicine isolated from flavonoid glucuronide, has drawn focus for its role in activating autophagy. In this study, the mRNA and protein level of a disintegrin and metalloproteinase with thrombospondin motifs-5 and matrix metalloproteinases-1 decreased with shikonin treatment, in the IL-1β-induced OA cell model. On the contrary, IL-1β-induced downregulation of Aggrecan and Collagen II was ameliorated following shikonin treatment. In addition, the upregulation of autophagy-related marker genes Beclin-1 and LC3II/LC3I in chondrocytes indicated that autophagy could be activated upon shikonin treatment. Moreover, shikonin’s promotion of anabolism in chondrocytes through autophagy activation corresponded with the results from the examination using chloroquine, an autophagy inhibitor. OA mouse cartilage tissues were stained with safranin O and fast green dyes. Results were analysed using the Osteoarthritis Research Society International (OARSI) score, and suggested that mice cartilage degeneration was alleviated after shikonin treatment. Altogether, we identified that shikonin might be a novel promising drug for OA treatment.

Downregulation of AMPK dependent FOXO3 and TFEB involves in the inhibition of autophagy in diabetic cataract

ABSTRACT Purpose Autophagy plays a crucial role in intracellular quality control of crystalline lens and AMPK has regulatory effect on autophagy. However, whether AMPK regulated autophagy is involved in diabetic cataract (DC) progression remains unknown. This study aims to investigate the AMPK-FOXO3 and AMPK-TFEB induced autophagy activity in DC patients. Materials and Methods First, anterior capsule specimens from DC and age-related cataract (ARC) patients were obtained to compare the expression difference of autophagy-related genes. The phosphorylation levels of AMPK, AKT, and mTOR and the expression of FOXO3 and TFEB were measured. Then, human lens epithelial cells (LECs, SRA 01/04) were cultured with 30 mM or 5.5 mM glucose, and AMPK activator (AICAR) and inhibitor (Compound C) were applied to further investigate the regulatory role of AMPK on autophagy. Results Compared with ARC patients, the expression of autophagy-related genes ATG5, FYCO1, ATG8, ATG12, Beclin1, and ULK1 in anterior capsules LECs of DC patients were significantly down-regulated. Meanwhile, AMPK and AMPK-dependent transcription factors, FOXO3 and TFEB were also inhibited. Similar results were found in high glucose (HG) treated SRA 01/04 model. Notably, this down-regulation of autophagy activity was rescued by AICAR in vitro, which was manifested by inhibition of AKT and mTOR phosphorylation and up-regulation of FOXO3, TFEB, Beclin1 and LC3B-II expression. Conclusions Down-regulation of AMPK-FOXO3 and AMPK-TFEB induced autophagy activity was found in both LECs of anterior capsule from DC patients and SRA 01/04 cells under HG condition, which may be the underlying mechanism of DC formation. Thus, targeting AMPK-induced autophagy may be a potential therapeutic approach for diabetic cataract.

Effects of Repeated Ovarian Stimulation on Ovarian Function and Aging in Mice.

Controlled ovarian hyperstimulation (COH) is routinely used in the in vitro fertilization and embryo transfer (IVF-ET) cycles to increase the number of retrieved mature oocytes. However, the relationship between repeated COH and ovarian function is still controversial. Therefore, we investigated whether repeated ovarian stimulation affects ovarian aging and function, including follicular development, autophagy, and apoptosis in follicles. Ovarian hyperstimulation in mice was induced by intraperitoneal injection with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Mice subjected to ovarian stimulation once were used as a control group and 10 times as an experimental group. Repeated injections with PMSG and hCG significantly reduced the number of primary follicles compared to a single injection. The number of secondary and antral follicles increased slightly, while the number of corpus luteum increased significantly with repeated injections. On the other hand, repeated injections did not affect apoptosis in follicles associated with follicular atresia. The expression of autophagy-related genes Atg5, Atg12, LC3B, and Beclin1, cell proliferation-related genes mTOR, apoptosis-related genes Fas, and FasL was not significantly different between the two groups. In addition, the expression of the aging-related genes Dnmt1, Dnmt3a, and AMH were also not significantly different. In this study, we demonstrated that repeated ovarian stimulation in mice affects follicular development, but not autophagy, apoptosis, aging in ovary. These results suggest that repetition of COH in the IVF-ET cycle may not result in ovarian aging, such as a decrease in ovarian reserve in adult women.

Low deacetylation degree chitosan oligosaccharide protects against IL-1β induced inflammation and enhances autophagy activity in human chondrocytes

Osteoarthritis (OA) is a degenerative joint disease, which can lead to joint pain, stiffness, deformity and dysfunction, that seriously affects the quality of life in patients. At present, the treatments of OA mainly include early pharmacological treatment and late joint replacement. However, current pharmacological treatment has limited efficacy and undesired side effects. Chitosan oligosaccharide (COS) is a kind of nontoxic and biodegradable oligo-saccharide, which is composed of 2–20 glucosamine or N-acetylglucosamine linked by β-1,4 glycosidic bond. Studies have shown that COS has significant biological properties like antimicrobial, anti-inflammatory, antioxidant, and anti-tumor, as well as immunoregulation ability. However, the effects of COS on OA have not been clarified. In this study, we explored the protective effects of COS with different degrees of deacetylation on chondrocytes stimulated by interleukin 1β (IL-1β) in vitro. The results showed that IL-1β inhibited cell proliferation and promoted cell apoptosis. Besides that, IL-1β increased the expression of the major chondro-degrading genes MMP13 and ADAMTS-5, while decreased the expression of COL2A and ACAN. COS with different degrees of deacetylation (HDACOS, MDACOS, LDACOS) had different effects on IL-1β induced inflammation. LDACOS had the most obvious anti-inflammatory effects to inhibit the expression of MMP13 and ADAMTS-5 while promoted the expression of COL2A and ACAN. In addition, we found that the expression of autophagy-related gene Beclin-1 was up-regulated, and the ratio of LC3-II/LC3-I was increased in the LDACOS group. Furthermore, transmission electron microscopy (TEM) analysis showed that the number of intracellular autophagosomes increased significantly with the treatment of LDACOS. Based on our research, we suggested that LDACOS could inhibit chondrocytes inflammation and promote cell autophagy, and might be a protective drug for the treatment of OA.

The therapeutic effect of Jiawei Danshen Decoction on myocardial ischemia-reperfusion injury by inhibiting H2S-mediated autophagy signaling pathway

ObjectiveTo investigate the protective effects of Jiawei Danshen Decoction (加味丹参饮, JWDSD) on myocardial ischemia-reperfusion injury (MIRI) via the regulation of serum Hydrogen sulfide (H2S) and cardiac Beclin1, light Chain 3A/B (LC3A/B), p62, and autophagy protein5 (ATG5). MethodsSeventy specific pathogen free (SPF) Sprague-Dawley (SD) rats were randomly assigned to seven groups (n = 10 in each group), including normal control, sham operation, MIRI model (model), ischemic preconditioning, NaHS, JWDSD, and JWDSD +CSE inhibitor (JWDSD + PPG) groups, and orally administered the indicated drugs for 14 d. Two hours after the last administration, the left anterior decreased branch of the coronary artery of each rat in model, NaHS, JWDSD, and JWDSD + PPG groups was ligated for 30 min and subsequently reperfused for 90 min to establish the MIRI model, and the rats in the sham operation group were only exposed to the thorax after surgery without coronary ligation. Blood samples were collected to detect H2S levels using an enzyme-linked immunosorbent assay (ELISA). Heart tissues were harvested for histopathological and immunohistochemical examination and quantitative reverse transcription polymerase chain reaction analysis of Beclin1 and ATG5 mRNA expression and Western blot analysis of Beclin1, LC3A/B, and p62 protein expression. Results(1) The serum H2S content in model group rats was significantly reduced (P < 0.01), JWDSD significantly increased the serum H2S content of model group rats (P < 0.01), and the CSE inhibitor (PPG) significantly reduced H2S levels in the JWDSD group rats (P < 0.01). (2) Compared with the normal control group, the myocardial tissue necrosis and cell destruction occurred in the MIRI model group, and JWDSD could alleviate the myocardial tissue necrosis of model rats, but the ameliorative effect of JWDSD could be reversed by PPG. (3) Beclin1, LC3A/B, and p62 expression levels in the heart tissues of the model group were significantly increased (P < 0.001), whereas decreased by JWDSD (P < 0.05, P < 0.01, and P < 0.001, respectively), and the inhibitory effects of JWDSD on Beclin1, LC3A/B, and p62 expression were partially reversed by PPG (P < 0.01, P < 0.05, and P < 0.01, respectively). (4) The expression levels of autophagy-related genes Beclin1 and ATG5 were significantly increased in the model group (P < 0.001). JWDSD clearly downregulated the expression levels of Beclin1 and ATG5 (P < 0.05 and P < 0.001, respectively), which were reversed by PPG (P < 0.001). ConclusionOur experimental data show that JWDSD can exhibit an anti-MIRI role by increasing endogenous H2S generation, and downregulating the expression of Beclin1, LC3A/B, p62 and ATG5, which are related to inhibiting autophagy signaling.

Fluoride regulates chondrocyte proliferation and autophagy via PI3K/AKT/mTOR signaling pathway

Fluorine is an essential trace element for human health. However, excessive fluoride intake causes skeletal fluorosis which affects cartilage development. Fluoride inhibited chondrocyte proliferation which is the initial and critical step of endochondral ossification, but the underlying mechanism has not been clearly illustrated. Mammalian target of rapamycin (mTOR) is an important protein kinase which modulates various cellular processes and is believed to be a central regulator of chondrocyte proliferation and autophagy. In this study, we explored the effect of fluoride on the proliferation and autophagy of chondrocytes and the regulatory role of mTOR signaling pathway. Our results suggested that NaF inhibited the protein expressions of proliferating cell nuclear antigen (PCNA) and pS6 in cultured fetal rat tibias. Furthermore, NaF significantly downregulated the expressions of mTOR signaling pathway-related genes, including PI3K, AKT, mTOR, 4EBP1 and S6K1 in mouse ATDC5 chondrogenic cell line. We also found that NaF increased autophagy in ATDC5 cells. The mRNA and protein levels of autophagy-related genes LC3, Beclin1 and p62 were significantly changed after NaF treatment. Further studies demonstrated that MHY1485, a small-molecular mTOR activator, totally reversed fluoride-induced promotion of autophagy. MHY1485 also recovered the downregulation of proliferative chondrocytes markers Sox9 and Type Ⅱ Collagen (Col2a1) induced by fluoride in ATDC5 cells. Taken together, our result demonstrate that fluoride suppressed proliferation and facilitated autophagy via PI3K/AKT/mTOR signaling pathway in chondrogenesis.