Hepatic phosphoenolpyruvate carboxykinase expression after gastric bypass surgery in rats with type 2 diabetes mellitus / 中华内分泌外科杂志

ABSTRACT

Objective To investigate mRNA expression of hepatic phosphoenolpyruvate carboxykinase (PEPCK) after gastric bypass surgery (GBS) in rats with type 2 diabetes mellitus (T2DM).Methods 36 male Goto-Kakizaki rats,aged 12 weeks,were randomly divided into GBS,sham operation with diet restriction (SO),and sham operation alone(control) groups(n=12 per group).The blood lipid levels and fasting plasma glucose (FPG)levels in rats before and 8 weeks after surgery were measured and compared.The insulin sensitivity index (ISI)was calculated.Real-time polymerase chain reaction (RT-PCR) and Western blot were used to detect the expression of PEPCK mRNA and protein in hepatocytes at 8 weeks after operation.Results 8 weeks after operation,the blood lipid levels [TC(1.25±0.08) mmol/L,TG (0.93±0.10) mmol/L,FFA(0.88±0.12) mmoUL] in GBS group were significantly lower than those before operation [TC (2.31 ±0.52) mmol/L,TG(1.44±0.27) mmol/L,FFA (1.08±0.06) mmol/L] (P＜0.05).The fasting blood glucose levels in GBS decreased from (11.73±0.37) mmol/L to (5.13±0.22) mmol/L (P＜0.05),and ISI in GBS group increased from (-5.78±0.10) to (-4.64±0.15) (P＜0.05).PEPCKmR-NA (3.97±0.30) and protein (1.60±0.31) expression significantly reduced (P＜0.05).Conclusion GBS can reduce blood glucose in T2DM rats while improving glucose tolerance and hyperglycemia,and the mechanism appears to be associated with a decrease of hepatic PEPCK mRNA and protein expression.