ABSTRACT
Objective: To observe the effect of Prunellae Spica extracts (PS) on the lipid metabolism in Zuker Diabetes Fatty (ZDF) rats based on AMP-activated protein kinase/acetyl CoA carboxylase (AMPK/ACC) signaling pathway.Method: The 32 male ZDF (fa/fa) type 2 diabetic rats were randomly divided into model group,metformin group (180 mg·kg-1·d-1),and low and high-dose PS groups (12.25,24.5 mg·kg-1·d-1),with 8 in each group.8 male Zuker Lean (ZL) rats were selected as normal group.Body weight and fasting blood glucose were monitored at the 0th,4th and 8th weeks after administration.After 8 weeks,abdominal aorta blood was collected,serum was frozen at-20℃ by centrifugation,liver tissue was frozen at-80℃,fixed with 4% paraformaldehyde and embedded in paraffin.Serum triglyceride (TG),cholesterol (CHO),low density lipoprotein cholesterol (LDL-C) and free fatty acid (FFA) levels were measured by radioimmunoassay.Fat droplets in hepatocytes were measured by oil red O staining.Gene expressions of AMP-activated protein kinase-alpha 2(AMPKα2),Acetyl CoA carboxylase (ACC) in liver were detected by real-time polymerase chain reaction (Real-time PCR).Protein expressions of p-AMPKα were observed by immuno-histochemical (IHC) method.Result: Compared with the normal group,the T2DM model group showed significant increases in serum levels of TG,CHO,LDL-C,FFA and lipid droplets in hepatocytes.AMPKα2 mRNA expression was decreased,while ACC1 and ACC2 mRNA expressions were increased significantly.p-AMPKα protein expression in liver was decreased significantly (PPα2,down-regulation in mRNA expressions of ACC1 and ACC2,and up-regulation in protein expression of p-AMPKα(PPConclusion:PS can effectively improve liver lipid metabolism in ZDF rats.Its mechanism may be related to the regulation of AMPK/ACC signaling pathway in liver.