Antidiabetic mechanism of Coptis chinensis polysaccharide through its antioxidant property involving the JNK pathway. (July 2015)

• Record Type: Journal Article
• Authors: Jiang, Shuang; Wang, Yahong; Ren, Dayong; Li, Jianrui; Yuan, Guangxin; An, Liping; Du, Peige; Ma, Jie
• Is Part Of: Pharmaceutical biology. Volume 53:Number 7(2015:Jul.)
• Page Start: 1022
• Page End: 1029
• Publication Date: 2015-07
• Subjects: Pharmacognosy -- Periodicals; Materia medica, Vegetable -- Periodicals; 615.321
• DOI: 10.3109/13880209.2014.952838
• Languages: English
• ISSNs: 1388-0209

Abstract

<abstract> <title>Abstract</title> <p> <italic>Context</italic>: Antidiabetic activity of <italic>Coptis chinensis</italic> Franch (Ranunculaceae) polysaccharide (CCPW) has been reported. However, its molecular mechanism remains unclear.</p> <p> <italic>Objective</italic>: An attempt was made to further verify the antidiabetic activity of CCPW on type 2 diabetes mellitus (T2DM) and elucidate the mechanism of antidiabetic activity.</p> <p> <italic>Materials and methods</italic>: Male Wistar rats were fed with high-fat diet (HFD) and injected with streptozotocin (STZ) to generate a T2DM model. Effects of CCPW on fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), glutathione (GSH), glutathione peroxidases (GSH-Px), superoxide dismutases (SOD), catalase (CAT), malondialdehyde (MDA), c-jun <italic>n</italic>-terminal kinase (JNK), phosphorylated insulin receptor substrate 1 (phospho-IRS1), phosphorylated phosphatidylinositol 3 kinase (phospho-PI3Kp85) and glucose transporter 4 (Glut4) were investigated.</p> <p> <italic>Results</italic>: FBG level of diabetic rats could be significantly inhibited by 51.2, 42.7, and 23.3% through administration of CCPW at doses of 200, 100, and 50 mg/kg b.w., respectively (<italic>p</italic> < 0.01). CCPW also could significantly reduce TG by 19.2, 12.1, and 7.4%, and TC by 24.2, 20.9, and 18.7%, respectively (<italic>p</italic> < 0.05 or <italic>p</italic> < 0.01). CCPW showed an obvious antioxidant effect through increasing GSH-Px, SOD, and CAT activities, and decreasing GSH and MDA contents (<italic>p</italic> < 0.05 or <italic>p</italic> < 0.01). Furthermore, CCPW could inhibit JNK and phospho-IRS1 expression and promote the expression of phospho-PI3Kp85 and Glut4 compared with those in the DM group (<italic>p</italic> < 0.05 or <italic>p</italic> < 0.01).</p> <p> <italic>Discussion and conclusion</italic>: CCPW can produce antidiabetic activity in rats with T2DM through its antioxidative effect, which is closely related to the JNK/IRS1/PI3K pathway.</p> </abstract>