Antidiabetic mechanism ofCoptis chinensispolysaccharide through its antioxidant property involving the JNK pathway

Abstract

Context: Antidiabetic activity of Coptis chinensis Franch (Ranunculaceae) polysaccharide (CCPW) has been reported. However, its molecular mechanism remains unclear. Objective: 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. Materials and methods: 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 n-terminal kinase (JNK), phosphorylated insulin receptor substrate 1 (phospho-IRS1), phosphorylated phosphatidylinositol 3 kinase (phospho-PI3Kp85) and glucose transporter 4 (Glut4) were investigated. Results: 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 (p50.01). 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 (p50.05 or p50.01). CCPW showed an obvious antioxidant effect through increasing GSH-Px, SOD, and CAT activities, and decreasing GSH and MDA contents (p50.05 or p50.01). 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 (p50.05 or p50.01). Discussion and conclusion: CCPW can produce antidiabetic activity in rats with T2DM through its antioxidative effect, which is closely related to the JNK/IRS1/PI3K pathway.

Coptidis rhizoma and its main bioactive components: recent advances in chemical investigation, quality evaluation and pharmacological activity

“…Meanwhile, the AGE accumulations and morphological abnormalities in the pancreas and liver were also improved [ 143 ]. It was also reported that the anti-diabetic effect of a water-soluble polysaccharide isolated from CR was achieved through its anti-oxidative effect involving the JNK pathway [ 144 , 145 ]. This water-soluble polysaccharide CCPW-1 could increase glutathione peroxidases, SOD, catalase activities and decrease glutathione and MDA contents while inhibiting JNK expression in high-fat with streptozotocin diet induced diabetic mice.…”

Pharmacokinetics and tissue distribution of coptisine in rats after oral administration by liquid chromatography–mass spectrometry

“…Coptis chinensis Franch, of the Ranunculaceae family, which is commonly known as Huanglian in China, is one of the 50 fundamental herbs used in traditional Chinese medicine (Li, Tsai, Damu, & Wu, ). Coptidis rhizoma, the dried rhizome of C. chinensis , has commonly been prescribed for various clinical effects, such as anti‐diabetic (Jiang et al, ), hypocholesterolemic and hypoglycemic (Yuan, Tu, Ye, & Wu, ), anti‐inflammatory (Choi et al, ; Cui et al, ), antioxidant (Ban et al, ), analgesia (Tjong et al, ) and neuroprotective (Friedemann et al, ) properties. Coptidis rhizoma is known to harbor a diversity of active isoquinoline‐type alkaloids such as berberine, coptisine, epiberberine, palmatine and jatrorrhizine.…”

Effect of ultrasonic degradation of hyaluronic acid extracted from rooster comb on antioxidant and antiglycation activities

“…The pathologic effects of AGEs are related to their ability to generate reactive oxygen species in addition to auto-oxidation reactions yielding radicals and other reactive intermediates (Lv et al 2014). Therefore, more attention has been paid to polysaccharides with antioxidant potential that may retard the process of AGEs formation by preventing further oxidation of glycation products (Deng et al 2003;Rout & Banerjee 2007;Jiang et al 2015).…”