ABSTRACT
BACKGROUND: Banxia Xiexin Decoction (BXXD) reportedly regulates glycolipid metabolism and inhibits pancreatic ß-cell apoptosis. This study is aimed at investigating the protective effect of BXXD on tert-butyl hydroperoxide- (t-BHP-) induced apoptosis in MIN6 cells and the underlying mechanisms. METHODS: MIN6 cells were preincubated with BXXD or liraglutide (Li) with or without PI3K inhibitor LY294002 (LY) for 12 h, following which t-BHP was added to induce MIN6 cell apoptosis. The protective effects of BXXD on MIN6 cells were evaluated by detecting cell viability and proliferation and glucose-stimulated insulin secretion (GSIS). The antiapoptotic effects were evaluated by Hoechst 33342 staining and terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL). Malondialdehyde and glutathione peroxidase content and superoxide dismutase activity were measured using commercial kits. The expression of PI3K/AKT/FOXO1 signaling pathway-related signal molecules, and that of apoptotic indicators Bax, P27, and Caspase-3, was quantified using western blotting. RESULTS: Preincubation with BXXD significantly improved t-BHP-induced proliferation inhibition and apoptosis and enhanced GSIS. t-BHP induced the generation of reactive oxygen species and inhibited the activities of antioxidant enzymes, which could be neutralized by pretreatment with BXXD. BXXD promoted the phosphorylation of AKT and FOXO1 in t-BHP-induced MIN6 cells. Moreover, BXXD attenuated the expression of related apoptotic indicators Bax, P27, and Caspase-3. LY abolished these effects of BXXD. CONCLUSION: BXXD protected MIN6 cells against t-BHP-induced apoptosis and improved insulin secretory function through modulation of the PI3K/AKT pathway and the downstream FOXO1, thus suggesting a novel therapeutic approach for type 2 diabetes mellitus (T2DM).
Subject(s)
Apoptosis/drug effects , Drugs, Chinese Herbal/pharmacology , Insulin-Secreting Cells/drug effects , Signal Transduction/drug effects , tert-Butylhydroperoxide/pharmacology , Animals , Caspase 3/metabolism , Cell Line , Forkhead Box Protein O1/metabolism , Glutathione Peroxidase/metabolism , Insulin-Secreting Cells/metabolism , Malondialdehyde/metabolism , Mice , Oxidative Stress/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolismABSTRACT
BACKGROUND: Sheng Mai San (SMS) has been proven to exhibit cardio-protective effects. This study aimed to explore the molecular mechanisms of SMS on hyperglycaemia (HG)-induced apoptosis in H9C2 cells. METHODS: HG-induced H9C2 cells were established as the experimental model, and then treated with SMS at 25, 50, and 100 µg/mL. H9C2 cell viability and apoptosis were quantified using MTT and Annexin V-FITC assays, respectively. Furthermore, Bcl-2/Bax signalling pathway protein expression and Fas and FasL gene expression levels were quantified using western blotting and RT-PCR, respectively. RESULTS: SMS treatments at 25, 50, 100 µg/mL significantly improved H9C2 cell viability and inhibited H9C2 cell apoptosis (p < 0.05). Compared to the HG group, SMS treatment at 25, 50, and 100 µg/mL significantly downregulated p53 and Bax expression and upregulated Bcl-2 expression (p < 0.05). Moreover, SMS treatment at 100 µg/mL significantly downregulated Fas and FasL expression level (p < 0.05) when compared to the HG group. CONCLUSION: SMS protects H9C2 cells from HG-induced apoptosis probably by downregulating p53 expression and upregulating the Bcl-2/Bax ratio. It may also be associated with the inhibition of the Fas/FasL signalling pathway.
Subject(s)
Apoptosis/drug effects , Drugs, Chinese Herbal/pharmacology , Hyperglycemia/physiopathology , Myocytes, Cardiac/cytology , Myocytes, Cardiac/drug effects , Protective Agents/pharmacology , Animals , Cell Survival/drug effects , Hyperglycemia/drug therapy , Hyperglycemia/genetics , Hyperglycemia/metabolism , Myocytes, Cardiac/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolismABSTRACT
The goal of the present study was to investigate the effect of explosion puffing and sun-drying on individual phenolic acids in four forms (free, esters, glycosides, and insoluble-bound), flavonoids, total phenolic content (TPC), and their antioxidant activity on jujube samples. Phenolic compounds were identified and quantified using high-performance liquid chromatography. Antioxidant capacity of jujube samples was evaluated by 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity and total reducing power. The results showed that all samples significantly differed in their phenolic contents, phenolic acid and flavonoid composition, and antioxidant activities. The explosion-puffed jujubes had the highest total gallic, p-hydroxybenzoic, vanillic, p-coumaric, ferulic acids, and rutin contents. Also, explosion-puffed jujubes contained a higher level of total phenolics and antioxidant activity than their counterparts. Among phenolic acid fractions in four forms, each form of phenolic acids in explosion-puffed jujubes had the most abundant content, followed by fresh and sun-dried jujubes. The glycosided and insoluble-bound phenolic acid fractions for each sample represented the highest TPC and the strongest antioxidant activity. The results indicated explosion puffing was a good choice for jujube processing.