ABSTRACT
Objective To investigate the effects of liraglutide on gene expression related to cholesterol metabolism in ApoE-/-mice with adiponectin deficiency. Methods Thirty six ApoE-/-mice fed with the high-fat diet were subdivided into four groups. One group was given 100 μl(1×109PFU) of adenoviral pAd-U6-GFP(GFP group, n=6). The second group received 100 μl of adenoviral pAd-U6-Acrp30(ADI group, n=10). The third group was given 100 μl of adenoviral pAd-U6-Acrp30 and liraglutide(HEA group, n=10) and the fourth group was given only 100 μl sterile saline(HF group, n=10). Insulin sensitivity and glucose metabolism were assessed by the hyperinsulinemic-euglycemic clamp technique using 3-[3H] glucose as a tracer. Plasma adiponectin level was evaluated using a commercially available ELISA kit. The mRNA expressions of genes involved in cholesterol metabolism were measured by quantitative realtime PCR. Results Fasting blood glucose(FBG), free fatty acids(FFA), total cholesterol, triglyceride, low density lipoprotein cholesterol, adiponectin, and fasting plasma insulin(FINS) in ADI mice were significantly higher than those in the other groups(P＜0.01), while high density lipoprotein cholesterol was significantly lower(P＜0.05). During the clamp, glucose infusion rate(GIR) in ADI group was significantly lower than the other groups(P＜0.01), and hepatic glucose production(HGP) significantly higher in ADI group(P＜0.01). The mRNA expressions of INSIG2 and LDLR in ADI group were significantly down-regulated in HEA group(P＜0.01 or P＜0.05), while HMGCR and SREBP-2 were significantly up-regulated in HEA group(P＜0.01 or P＜0.05). Conclusions Liraglutide regulates a number of genes involved in cholesterol metabolism and ameliorates hypercholesterolemia by elevating plasma adiponectin level.