二甲双胍及游泳运动对肥胖大鼠血清Ghrelin水平的影响

Effects of metformin and swimming exercise on serum Ghrelin levels of high-fat-diet fed obesity rats

目的研究二甲双胍、游泳运动及联合干预对肥胖大鼠血清Ghrelin水平的影响,探讨Ghrelin与肥胖、代谢紊乱之间的关系。方法SD大鼠70只随机分为普食(ND,n=10)组和高脂(HD,n=60)组,16周HD组成功建立肥胖模型后(n=40)随机分为:肥胖对照(OB)组,二甲双胍(MET)组,游泳(SWI)组,二甲双胍+游泳(MAS)组,各10只。MET组予二甲双胍灌胃200mg/(kg·d),SWI组进行游泳运动,MAS组予二甲双胍灌胃200mg/(kg·d)联合游泳运动,SWI组、OB组及ND组等剂量蒸馏水灌胃,共6周。分别测定干预前及干预6周后各组体重(BW)、空腹血糖(FPG)、甘油三酯(TG)、总胆固醇(TCH)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)及Ghrelin。结果①干预前,肥胖模型各组较ND组BW、FPG、TG、TCH、FINS、HOMA-IR升高,Ghrelin降低,差异有统计学意义(P<0.05或P<0.01),肥胖模型各组间各指标差异无统计学意义(P>0.05)。②干预后,MET组、SWI组、MAS组较OB组BW、TG、TCH、FPG、FINS、HOMA-IR降低,Ghrelin水平升高,差异有统计学意义(P<0.05或P<0.01),但各干预组间差异无统计学意义(P>0.05)。③相关性分析显示FINS与Ghrelin呈负相关(r=-0.817,P<0.05)。结论二甲双胍及游泳运动可显著升高肥胖大鼠血清Ghrelin水平,并可改善代谢紊乱。Ghrelin可能是肥胖发生发展过程及机体长期能量调控的重要因素。

Objective To investigate the effects of metfoimin, swimming exercise and the combination of both interventions on Ghrelin levels of high-fat-fed obesity rats and to explore the relationship between Ghrelin and obesityrelated metabolic disorders. Methods 70 SD rats were randomly divided into two groups in which 10 rats were fed with normal control diet as normal diet group （ND） , and the remaining 60 were fed 1Mth high fat diet as high fat diet group （HD）. After 16 weeks obesity model （n =40） was established from HD group and was randomly divided into four groups ： obesity group （ OB）, metformin group （ MET）, swimming exercise group （ SWI）, and the combi- nation of metformin and swimming exercise group （MAS） with 10 rats in each groups. MET group was treated with metformin 200 mg/（kg ·d） , SWI group was assigned to swimming exercise, and MAS group was treated with the combination of mefformin ,200 mg/（ kg·d） ] and swimming exercise. SWI group, OB group and ND group were treated with distilled water. Body weight （BW）, fasting plasma glucose（FPG）, triglyceride （TG）, total cholesterol （TCH）, fasting insulin （FINS）, HOMA-IR and fasting Ghrelin were detected before and after the 6 weeks of treatment. Results （1） Before the treamtment BW, FPG, TG, TCH, HOMA-IR and FINS levels of each groups in obesity model increased and Ghrelin level decreased significantly in contrast to those in ND group （P 〈 0. 05 or P 〈 0. 01 ）. There were no statistical differences in the parameters between the four groups of the obesity model（P 〉 0. 05）. （2） After 6 weeks＇ treatment BW, FPG, TG, TCH, and FINS in MET group, SWI group and MAS group were down-regulated compared to those in OB group（P 〈0.05 or P 〈0.01 ）, and Ghrelin levels were dramatically higher than that of OB group（P 〈 0.05）, but the parameters showed no difference between the three intervention groups （P 〉0. 05）. （3） The level of FINS correlated negatively with that of Ghrelin（r = -0. 817 ,P 〈0. 05）. Conclusion Metformin and swimming exercise can increase ghrelin levels of obesity rats, and improve metabolic disorders remarkably. Ghrelin may play important roles in the etiology and pathophysiology of obesity and maybe a key participant element in the long-term energy regulation.