The Effect Of Calorie Restriction On The Expression Of The Liver's Glyconeogenesis Genes Of Rats With High Fat Diet

Objective: To observe the effect of calorie restriction on the mRNA expression of Forkhead box O1 (FoxO1), phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G-6-P) of liver in high fat diet fed rats and explore the possible mechanism that calorie restriction improves blood glucose and lipid level.Methods: 24 normal 6-week-old male Wistar rats were randomly divided into three groups: normal chow group (NC, n=7), high fat diet group (HF, n=9) and calorie restriction group (CR, n=8). They were fed for 12 weeks. At the end of the experiment, the rats were sacrificed and their fasting blood glucose (FBG), fasting insulin (INS), triglycerides (TG), total cholesterol (TC) were measured. Their visceral fat (VF) and body weight (BW) were weighted and VF/BW was calculated. Gene expression was investigated by using the semi-quantitative RT-PCR methods from liver tissue. Liver histology was detected by HE dyeing.Results: As compared with NC group, HF group rats developed visceral obesity which was accompanied by higher FPG, plasma INS, TG, TC. The level of FoxO1, PEPCK, G-6-P in HF group increased by 18.9%, 33.8%, and 24.6%, respectively(P<0.05). Pathology of liver steatosis was observed by light microscope. After calorie restriction, their BW and VF decreased obviously, with reduced FPG, INS, TG and TC. The level of FoxO1, PEPCK, G-6-P decreased by 26.6%,35.0%,34.3%(P<0.05)comparing with HF group. Meanwhile, liver steatosis was also improved.Conclusion: A high fat diet induced expressions of FoxO1, PEPCK, G-6-P, thus promote gluconeogenesis, resulting in high FBG. Calorie restriction can inhibit the expressions of FoxO1, PEPCK, and G-6-P, strengthen insulin signal conduction, suppress gluconeogenesis and thus regulate glycometabolism.