Mechanism of electroacupuncture for regulation of lipid production and improvement in obesity by mediating Wnt/ β-catenin pathway through activating SIRT1 / 中国针灸

ABSTRACT

OBJECTIVE@#To explore the mechanism of electroacupuncture (EA) for the regulation of lipid production and improvement in obesity by mediating Wnt/β-catenin pathway through activating silent information regulator 1 (SIRT1).@*METHODS@#Of 75 Wistar male rats, 10 rats were selected randomly as the normal group and fed with standard diet. The rest rats were fed with high-fat diet for 8 weeks to establish the obesity model. Forty rats of successful modeling were randomized into a model group, an EA group, an EA plus inhibitor group (EA+I group) and an agonist group, 10 rats in each one. In the EA group, EA was applied at "Guanyuan" (CV 4), "Zhongwan" (CV 12), "Zusanli" (ST 36) and "Fenglong" (ST 40), with continuous wave, 2 Hz in frequency and around 1 mA in intensity. The needles were retained for 20 min. In the EA+I group, sirtinol solution was injected from caudal vein and EA was exerted simultaneously. In the agonist group, resveratrol solution was given by intragastric administration. The intervention of the above three groups was given once every two days, 3 times a week, consecutively for 8 weeks. Before and after intervention, body mass and Lee's index were recorded in the rats of each group. After intervention, the levels of serum total cholesterol (TC), triglyceride (TG) and free fatty acid (FFA) were detected in the rats of each group. After intervention, the mass of white adipose tissue (WAT) and the area of adipocytes were compared in the rats among the 5 groups. Using Western blot method, the protein expressions of SIRT1, glycogen synthase kinase-3β (GSK3β), β-catenin, cyclin D1 and peroxisome proliferators-activated receptor γ (PPARγ) were detected in WAT in the rats of each group.@*RESULTS@#After intervention, compared with the model group, the body mass and Lee's index were reduced in the rats of the EA group and the agonist group (@*CONCLUSION@#Electroacupuncture remarkably improves the body mass, Lee's index and blood lipid metabolism and reduces WAT mass and adipocyte size in obesity model rats, which is probably related to up-regulating the protein expression of SIRT1 in WAT, activating Wnt/β-catenin pathway and inhibiting the expression of PPARγ of downstream lipogenic gene so as to affect lipid production.