Berberine Inhibits Gluconeogenesis in Skeletal Muscles and Adipose Tissues in Streptozotocin-induced Diabetic Rats via LKB1-AMPK-TORC2 Signaling Pathway

SummaryThe effect and potential molecular mechanisms of berberine on gluconeogenesis in skeletal muscles and adipose tissues were investigated. After adaptive feeding for one week, 8 rats were randomly selected as the normal group and fed on a standard diet. The remaining 32 rats were fed on a high-fat diet and given an intravenous injection of streptozotocin (STZ) for 2 weeks to induce the diabetic models. The diabetic rat models were confirmed by oral glucose tolerance test (OGTT) and randomly divided into 4 groups (n=8 each), which were all fed on a high-fat diet. Berberine (3 g/kg per day) or metformin (183 mg/kg per day) was intragastrically administered to the diabetic rats for 12 weeks, serving as berberine group and metformin group respectively. 5-aminoimidazole-4-carboxamide1- β-D-ribofuranoside [AICAR, an agonist of AMP-activated protein kinase (AMPK), 0.5 mg/kg per day] was subcutaneously injected to the diabetic rats for 12 weeks, serving as AICAR group. The remaining 8 diabetic rats served as the model group, which was given a 0.5% carboxyl methylcellulose solution b y oral gavage. Fasting serum insulin (FINS), OGTT as well as lipid parameters were tested by commercial kit. The protein levels of liver kinase B1 (LKB1), AMPK, phosphorylated AMP-activated protein kinase (p-AMPK), transducer of regulated CREB activity 2 (TORC2), phosphorylated transducer of regulat ed CREB activity 2 (p-TORC2), phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G...
Source: Journal of Huazhong University of Science and Technology -- Medical Sciences -- - Category: Research Source Type: research