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Background: This study will be aimed at investigating the effects of Baihu Renshen decoction (BHRS) on type 2 diabetes rats and on macromolecular enzyme 1 (PINK1)/E3 ubiquitin protein ligase (Parkin) pathway. Methods: The experiment was divided into four groups: control group, model group, metformin group and BHRS low-dose group and high-dose group. Forty male rats were selected as samples and randomly assigned to at least one test group. Finally, there are 18 rats in each group. Except for the control group, the rats within the different teams got a high-fat diet associate in nursing an intraperitoneal injection of streptozotocin to make a type 2 diabetes mellitus (T2DM) rat model. The organic chemistry and inflammatory indexes of rats in every cluster were analyzed and compared once four weeks of intragastric administration of comparable reagents to review the therapeutic impact of BHRS on T2DM. In addition, we determined the pathological changes of ductal gland tissue of T2DM rats after treatment, and compared the expression of mitochondrial phagocytosis related proteins in ductal gland tissue of rats in each group. Results: FBG, LDL-C, TC, TG, MDA, IL-1, IL-6, TNF-, and mitophagy-related proteins COXIV, P62, VDAC1, and TOM20 were elevated in the model group compared to the control group, while HDL-C, SOD, GSH-Px, and mitophagy-related proteins PINK1, Parkin, and LC3II/I were decreased (P < 0.05 or P < 0.01). The expressions of FBG, TC, TG, LDL-C, MDA, IL-1, IL-6, TNF-, and mitophagy-related proteins COXIV, P62, VDAC1, and TOM20 were lowered in the BHRS group, while the expressions of HOMA-, HDL-C, SOD, GSH-Px, and mitophagy-related proteins PINK1, Parkin, and LC3II/I were (P < 0.05 or P < 0.01). After therapy with BHRS, hematoxylin-eosin staining showed that the intensity of pancreatic acinar staining increased, and islet cells became clear boundaries that were, regularly arranged, and with reduced vacuoles reduced. Conclusion: BHRS has a clear therapeutic effect on T2DM, which may be achieved by regulating mitochondrial autophagy through the PINK1/Parkin pathway. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of acacetin (Aca) on the proliferation, apoptosis and migration of liver cancer HepG2 cells by regulating PTEN induced kinase 1 (PINK1)/E3 ubiquitin protein ligase (Parkin) pathway mediated mitochondrial autophagy. Methods Liver cancer HepG2 cells were divided into the control group (normally cultured HepG2 cells), the Aca group (10 µmol/L Aca), the PINK1 small interfering RNA negative control (si-NC) group (transfected with si-NC), the PINK1 small interfering RNA (si-PINK1) group (transfected with si-PINK1), the Aca+si-NC group (treated with 10 µmol/L Aca after transfection of si-NC) and Aca+si-PINK1 group (treated with 10 µmol/L Aca after transfection of si-PINK1). Cell counting kit-8 (CCK-8) method was used to detect cell proliferation. Flow cytometry was used to detect cell apoptosis. Transwell test was used to detect cell migration. Transmission electron microscope was used to observe the formation of autophagosomes. Western blot assay was used to detect expression levels of autophagy related proteins [Beclin1, microtubule associated protein 1 light chain 3 (LC3)-Ⅰ and LC3-Ⅱ］and PINK1/Parkin pathway related proteins in cells. Results Compared with the control group, the survival rate and the number of migrating of HepG2 cells were significantly decreased in the Aca group, and the apoptosis rate, number of autophagy bodies, expression levels of Beclin-1, LC3-Ⅱ/LC3-Ⅰ, PINK1 and Parkin protein were increased significantly (P＜0.05). The survival rate and the number of migrating of HepG2 cells were significantly increased in the si-PINK1 group, and the apoptosis rate, number of autophagy bodies, expression levels of Beclin-1, LC3-Ⅱ/LC3-Ⅰ, PINK1 and Parkin protein were decreased significantly (P＜0.05). Compared with the Aca group and the Aca+si-NC group, the survival rate and the number of migrating of HepG2 cells were significantly increased in the Aca+si-PINK1 group, and the apoptosis rate, number of autophagy bodies, expression levels of Beclin-1, LC3- Ⅱ/LC3- Ⅰ, PINK1 and Parkin protein were decreased significantly (P＜0.05). Conclusion Aca may inhibit the proliferation and migration and promote cell apoptosis of liver cancer HepG2 cells by activating mitochondrial autophagy mediated by PINK1/Parkin pathway. [ABSTRACT FROM AUTHOR]

Background: Corn peptides, a novel food prepared from corn gluten meal (CGM) by enzymatic hydrolysis or microbial fermentation, have attracted considerable interest owing to their various bioactive properties. However, the underlying mechanism of corn peptides attenuate non-alcoholic fatty liver disease (NAFLD) remains unclear. Objective: This study aimed to investigate the effect of corn peptides in NAFLD and to decipher the underlying mechanisms. Design:NAFLD was induced by a high-fat diet (HFD) for 10 weeks. Corn peptides were administered during the period. Human hepatocellular carcinomas (HepG2) cells induced by free fatty acids were used for this mechanism study. Results: Corn peptides alleviated HFD-induced histopathological changes, disorders of lipid metabolism, and mitochondrial damage. Moreover, corn peptides blocked mitophagy suppression by HFD based on the increased LC3, ATG7 expressions, as well as decreased P62 levels. Corn peptides increased the expression of proteins involved in fatty acid β-oxidation, such as PPARα and PGC-1α. Corn peptides also improved the Ser/Thr kinase PINK1 (PINK1) and the E3 ubiquitin ligase Parkin (Parkin) translocation to mitochondria, which is confirmed by immunofluorescence. Furthermore, stable knockdown of PINK1 by PINK1 SiRNA in HepG2 inhibited PINK1-Parkin-associated mitophagy and resulted in lipid accumulation. Conclusion: Corn peptides improved cell injury and ameliorated mitochondrial dysfunction and lipid accumulation via PINK1/Parkin-mediated autophagy in NAFLD. Thus, corn peptides could be a promising nutritional molecule with natural functions for preventing NAFLD. [ABSTRACT FROM AUTHOR]

Objective This study aimed to explore the specific mechanism, mediated by the reactive oxygen species (ROS) and PINK1/Parkin pathway, of the mitochondrial autophagy of human periodontal ligament cells (hPDLCs) under starvation conditions. Methods hPDLCs were isolated and cultured from normal periodontal tissues. Earle's balanced salt solution (EBSS) was used to simulated a starvation environment and thus stimulate hPDLCs mitochondrial autophagy. N-Acetyl-L-cysteine (NAC) was used to inhibit ROS production to explore the role of ROS in hPDLC mitochondrial autophagy. Cyclosporin A was used to inhibit the PINK1/Parkin pathway to study the role of ROS and the PINK1/Parkin pathway in hPDLCs activation under starvation. The mitochondrial membrane potential was detected by flow cytometry with a JC-1 mitochondrial membrane potential detection kit. The morphological structure of mitochondria and the formation of mitochondrial autophagosome were observed by transmission electron microscopy. Mito tracker red cmxros and lyso tracker green staining were used to observe the localization of mitochondria and lysosomes. The formation intensity of ROS was detected with a DCFH-DA ROS fluorescent probe. The expression levels of mitochondrial autophagy genes (Tomm20 and Timm23) and the PINK1/Parkin pathway were detected by real-time quantitative polymerase chain reaction (RT-qPCR). The expression levels of mitochondrial autophagy proteins (Tomm20 and Timm23) and PINK1/Parkin protein were detected by Western blot. Results EBSS starvation for 30 min induced the strongest activation of hPDLCs mitochondrial autophagy, increased the expression of ROS, downregulated the expression of mitochondrial autophagy-related genes (Tomm20 and Timm23) (P<0.001), and upregulated the PINK1/Parkin pathway (P<0.001). After NAC inhibited ROS production, mitochondrial autophagy was also inhibited. Meanwhile, the expression of Tomm20 and Timm23 was upregulated (P<0.001 and P<0.05), and the expression of the PINK1/parkin pathway (P<0.001 and P<0.05) was down regulated. When cyclosporin A inhibited the expression of the PINK1/Parkin pathway (P<0.05 and P<0.05), it reversed the mitochondrial autophagy of hPDLCs (P<0.001 and P<0.01) and also upregulated the expression of Tomm20 and Timm23 (P<0.001 and P<0.01). Conclusion ROS enhanced the mitochondrial autophagy of hPDLCs primarily through the PINK1/Parkin pathway under starvation conditions. [ABSTRACT FROM AUTHOR]

[Objectives] The aim of this study was to investigate the effects of decabromodiphenyl ether(BDE-209) exposed to broilers on kidney damage,and to explore the potential nephrotoxicity and mechanisms. [Methods] One day-old 150 male AA broilers were randomly allotted to 5 groups with 6 replicates per group and 5 broilers per replicate. The broilers were exposed to BDE-209 concentrations with 0,0.004,0.04,0.4,4.0 g·kg-1 added to a standard diet for 42 days,respectively. At the end of the experiment,the concentration of blood urea nitrogen(BUN) and creatinine(CRE) in serum as well as kidney oxidative stress indexes were measured,and the histological and morphological structure and mitochondrial membrane potential of kidney were observed. The expression of autophagy proteins involving in p62,microtubule-associated protein 1 light chain 3(LC3) and PTEN-inducible kinase 1(PINK1)/Parkin signaling pathway were analyzed by fluorescence immunohistochemistry,real-time PCR and western blot. [Results] Compared with control,kidney injury was observed at different BDE-209 treatment groups,including glomerular enlargement and cellular composition increased,renal tubular edema and cytoplasmic porosity and mitochondrial membrane potential decreased in kidney. Additionally,the levels of BUN,CRE in serum increased significantly(P<0.05) when the content of BDE-209 was upper 0.04 g·kg-1,and the activities of SOD and GSH-Px in 0.4 and 4.0 g·kg-1 BDE-209 groups decreased significantly(P<0.05),the concentration of MDA increased in 0.04,0.4 and 4.0 g·kg-1 BDE-209 groups(P<0.05). Moreover,the expression level of p62 and the ratio of LC3-â…¡/LC3-â…  increased(P<0.05),and the PINK1 expression were also significantly up-regulated in kidney tissues(P<0.05). [Conclusions] BDE-209 exposure can cause kidney damage,and the underlying mechanisms may be that BDE-209 exacerbate oxidative stress,then activate PINK1/Parkin pathway to induce mitochondrial injury,promote the transformation of autophagy protein LC3-â…  to LC3-â…¡ and the accumulation of p62 protein,which hindere the degradation of autophagy and resulted in the renal injury. 参考文献/References: [Objectives] The aim of this study was to investigate the effects of decabromodiphenyl ether(BDE-209) exposed to broilers on kidney damage,and to explore the potential nephrotoxicity and mechanisms. [Methods] One day-old 150 male AA broilers were randomly allotted to 5 groups with 6 replicates per group and 5 broilers per replicate. The broilers were exposed to BDE-209 concentrations with 0,0.004,0.04,0.4,4.0 g·kg-1 added to a standard diet for 42 days,respectively. At the end of the experiment,the concentration of blood urea nitrogen(BUN) and creatinine(CRE) in serum as well as kidney oxidative stress indexes were measured,and the histological and morphological structure and mitochondrial membrane potential of kidney were observed. The expression of autophagy proteins involving in p62,microtubule-associated protein 1 light chain 3(LC3) and PTEN-inducible kinase 1(PINK1)/Parkin signaling pathway were analyzed by fluorescence immunohistochemistry,real-time PCR and western blot. [Results] Compared with control,kidney injury was observed at different BDE-209 treatment groups,including glomerular enlargement and cellular composition increased,renal tubular edema and cytoplasmic porosity and mitochondrial membrane potential decreased in kidney. Additionally,the levels of BUN,CRE in serum increased significantly(P<0.05) when the content of BDE-209 was upper 0.04 g·kg-1,and the activities of SOD and GSH-Px in 0.4 and 4.0 g·kg-1 BDE-209 groups decreased significantly(P<0.05),the concentration of MDA increased in 0.04,0.4 and 4.0 g·kg-1 BDE-209 groups(P<0.05). Moreover,the expression level of p62 and the ratio of LC3-Ⅱ/LC3-Ⅰ increased(P<0.05),and the PINK1 expression were also significantly up-regulated in kidney tissues(P<0.05). [Conclusions] BDE-209 exposure can cause kidney damage,and the underlying mechanisms may be that BDE-209 exacerbate oxidative stress,then activate PINK1/Parkin pathway to induce mitochondrial injury,promote the transformation of autophagy protein LC3-Ⅰ to LC3-Ⅱ and the accumulation of p62 protein,which hindere the degradation of autophagy and resulted in the renal injury. 参考文献/References: [ABSTRACT FROM AUTHOR]

Ischemia/reperfusion (I/R) is a well‐known injury to the myocardium, but the mechanism involved remains elusive. In addition to the well‐accepted apoptosis theory, autophagy was recently found to be involved in the process, exerting a dual role as protection in ischemia and detriment in reperfusion. Activation of autophagy is mediated by mitochondrial permeability transition pore (MPTP) opening during reperfusion. In our previous study, we showed that MPTP opening is regulated by VDAC1, a channel protein located in the outer membrane of mitochondria. Thus, upregulation of VDAC1 expression is a possible trigger to cardiomyocyte autophagy via an unclear pathway. Here, we established an anoxia/reoxygenation (A/R) model in vitro to simulate the I/R process in vivo. At the end of A/R treatment, VDAC1, Beclin 1, and LC3‐II/I were upregulated, and autophagic vacuoles were increased in cardiomyocytes, which showed a connection of VDAC1 and autophagy development. These variations also led to ROS burst, mitochondrial dysfunction, and aggravated apoptosis. Knockdown of VDAC1 by RNAi could alleviate the above‐mentioned cellular damages. Additionally, the expression of PINK1 and Parkin was enhanced after A/R injury. Furthermore, Parkin was recruited to mitochondria from the cytosol, which suggested that the PINK1/Parkin autophagic pathway was activated during A/R. Nevertheless, the PINK1/Parkin pathway was effectively inhibited when VDAC1 was knocked‐down. Taken together, the A/R‐induced cardiomyocyte injury was mediated by VDAC1 upregulation, which led to cell autophagy via the PINK1/Parkin pathway, and finally aggravated apoptosis. [ABSTRACT FROM AUTHOR]

Dajianzhong decoction (DJZ) is a classical famous formula for treating yang-deficiency-syndrome in traditional Chinese medicine and recorded in Jin-Kui-Yao-Lue in Dynasty of Dong Han. Cognitive aging can present similar features of mitochondrial energy deficits to the clinical features of Yang deficiency. However, there is poor understanding of the effects of DJZ treatment on mitophagy in cognitive aging. The aims of this work were to decipher the effectiveness and mechanism of DJZ against cognitive aging, focusing on mitophagy. YFP-Parkin HeLa cells, D-galactose (D-gal) -induced mice (500 mg/kg for 35 d, s. c.) and SH-SY5Y cells (80 mg/ml for 6 h) were established. Firstly, the formation of YFP-Parkin puncta (a well-known mitophagy marker) in YFP-Parkin HeLa cells was employed to discover the mitophagy induction of DJZ. Moreover, the genes and proteins related to PINK1/Parkin pathway and mitochondrial functions were evaluated after treatment with DJZ in vivo (3.5 g/kg or 1.75 g/kg, i. g, 35 d) and in vitro (0.2, 2 and 20 μg/ml, 12 h). Furthermore, the effectiveness of DJZ (3.5 g/kg or 1.75 g/kg, i. g) for alleviating cognitive aging and nerve damage was measured in D-gal mice. Finally, siPINK1 was applied to reverse validation of DJZ in vitro. The formation of YFP-Parkin puncta in YFP-Parkin HeLa cells was markedly induced by DJZ in a dose-dependent manner. The immunofluorescence intensity of Parkin and the protein expression of Parkin in mitochondrial membrane in D-gal mice were significantly increased after treatment of DJZ. The inhibition of PINK1/Parkin pathway in D-gal-induced mice and SH-SY5Y cells was significantly activated by DJZ. Simultaneously, the impairment of mitochondrial functions induced by D-gal were markedly reversed by DJZ. In addition, DJZ significantly ameliorated the neuropathological injury and cognitive declines in D-gal mice. Finally, after PINK1 was knocked down by siPINK1 in vitro, the neuroprotective effects of DJZ and the Parkin enhancement effect of DJZ were markedly reversed. Our findings firstly showed DJZ could relieve cognitive aging through facilitating PINK1/Parkin-mediated mitophagy to protect against mitochondrial functions, indicating DJZ may be regarded as a promising intervention in cognitive aging. [Display omitted] • Dajianzhong decoction consisting of three herbs improves cognitive performance of aging mice. • Dajianzhong decoction could rescue energy crisis caused by mitochondrial damage. • Dajianzhong decoction targets the PINK1/Parkin pathway to mediate mitochondrial autophagy. [ABSTRACT FROM AUTHOR]

Mitophagy is the process of selective clearance of damaged mitochondria by autophagy. There are several regulatory mechanisms for mitophagy, and the PINK1/Parkin pathway is considered the main pathway for mitophagy. Recent studies have shown that PINK1/Parkin-mediated mitophagy plays an important role in the pathogenesis of various diseases including Parkinson’s disease. This article introduces the mechanism of PINK1/Parkin-mediated mitophagy and its role in various liver diseases including nonalcoholic fatty liver disease, liver fibrosis, and hepatocellular carcinoma, in order to provide new clues and ideas for the treatment of diseases. [ABSTRACT FROM AUTHOR]

Context and objective: Recent reports have highlighted the relationship between cadmium (Cd) and autophagy, however, whether Cd can activate mitophagy remains enigmatic. This study aims to investigate the effects of Cd on mitophagy and its potential mechanism. Methods: Mice were intraperitoneally injected with Cd for 3 d. Mitochondrial membrane potential (MMP), mitophagosomes, LC3-II/LC3-I ratio, PINK1 level and mitochondrial mass were evaluated to indicate the effects of Cd on mitophagy. To elucidate the mechanism, reactive oxygen species (ROS) scavenger N-acetyl- l-cysteine (NAC) or acetyl- l-carnitine (ALC) as well as the mitophagy inhibitor cyclosporine A (CsA) were introduced to verify the role of ROS in mitophagy. Results and conclusions: The results showed that Cd significantly induced MMP collapse and typical mitophagosomes formation, increased LC3-II/LC3-I ratio and PINK1 level, and decreased mitochondrial mass, revealing that Cd could induce mitophagy. However, NAC or ALC pretreatment markedly decreased Cd-induced ROS and simultaneously rescued MMP and mitochondrial mass, suggesting ROS played a crucial role in regulating mitophagy. NAC or ALC also dramatically lessened PINK1 level and mitochondrial accumulation of Parkin, indicating that ROS were related to PINK1/Parkin pathway. Notably, CsA compromised Cd-induced mitophagy, PINK1 accumulation and Parkin translocation while failed to block ROS increase, suggesting ROS functioned as an upstream signal for PINK1/Parkin pathway. Taken together, the results indicated that Cd induced ROS-mediated mitophagy through PINK1/Parkin pathway in kidneys of mice. The present study proposes a new perspective to evaluate the nephrotoxicity and its molecular mechanism under Cd exposure in vivo. [ABSTRACT FROM AUTHOR]

The purpose of this study was to reveal the therapeutic efficacy and underlying mechanism of cannabinoid type 2 receptor agonist (AM1241) on myocardial ischemia-reperfusion injury (MIRI) in rats. We established a rat myocardial ischemia/reperfusion (I/R) model and H9c2 hypoxia/reoxygenation (H/R) model. ELISA was used to determine the concentrations of cardiac troponin I (cTnI), creatine kinase-MB (CK-MB), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) in plasma. EB/TTC staining was performed to observe the myocardial infarct size. Besides, the pathological changes of myocardial tissue were identified via H&E staining and Masson's trichrome staining. TUNEL assay was performed to examine myocardial apoptosis. Then, the protein expression of Pink1, Parkin and autophagy-related markers (Beclin-1, P62 and LC3) were detected by Western blot, and autophagy was evaluated by Mitotracker staining. The results of EB/TTC staining, H&E staining, Masson's trichrome staining and cardiac enzymes measuring showed that AM1241 treatment significantly diminished infarct size, the structural abnormalities and the activities of cardiac enzymes (cTnI, CK-MB, AST and LDH). AM1241 also significantly reduced the number of TUNEL-positive cells induced by I/R in a dose-dependent manner. Furthermore, AM1241 activated Pink1/Parkin signaling pathway and upregulated autophagy level. AM1241 exerts a protective effect against MIRI in rats by inducing autophagy through the activation of Pink1/Parkin pathway. [ABSTRACT FROM AUTHOR]