运动对视黄醇结合蛋白4诱导的脂代谢异常鼠肝脏SREBP-1c信号通路和脂肪合成的影响

Effects of exercise on SREBP-1c signal pathway and fat synthesis of the liver of mice with dyslipidemia induced by RBP4

研究运动对RBP4诱导的脂代谢异常鼠肝脏SREBP-1c信号通路和脂肪合成的影响;重组人RBP4注射建立脂代谢异常鼠模型,设一次性运动组(RBP4 One-time exercise group,ROE组)、8周有氧运动组(RBP4 aerobic exercise group,RAE组)和安静对照组(RBP4 control group,RC组)。结果发现:ROE组血清RBP4水平与RC组比较非常显著降低(P<0.01),血清TG和肝脏TG含量无显著性改变(P>0.05)。RAE组血清RBP4、TG和肝脏TG含量与RC组和ROE组比较均非常显著降低(P<0.01)。与RC组比较,ROE组和RAE组肝脏SREBP-1c m RNA表达均非常显著降低(P<0.01);ROE组SREBP-1c蛋白表达、FASm RNA和FAS蛋白表达均无显著性改变(P>0.05);RAE组SREBP-1c、FAS的m RNA和蛋白表达比ROE组均非常显著减少(P<0.01)。结果说明RBP4显著使小鼠肝脏SREBP-1c基因和蛋白表达增加、激活SREBP-1c信号通路、促进肝脏脂肪合成。8周有氧运动抑制了RBP4在肝脏的脂肪合成促进作用,改善脂代谢,机制涉及降低RBP4水平,减少肝脏SREBP-1c基因和蛋白表达,抑制SREBP-1c信号通路的激活,降低肝脏脂肪合成功能。

In order to study the effects of exercise on SREBP-1c signal pathway and fat synthesis of the liver ofmice with dyslipidemia induced by RBP4, the author established a dyslipidemia mouse model by means of RBP4intraperitoneal injection, set up a one-time exercise group （ROE）, an 8-week aerobic exercise group （RAE） and acalm control group （RC）, and revealed the following findings： comparing the mice in group ROE with the mice ingroup RC, serum RBP4 level decreased significantly （P〈0.01）, serum TG and liver TG contents had no significantchange （P〉0.05）; comparing the mice in group RAE with the mice in groups RC and ROE, serum RBP4, serum TGand liver TG contents decreased significantly （P〈0.01）; comparing the mice in groups ROE and RAE with the micein group RC, liver SREBP-1c mRNA expression decreased significantly （P〈0.01）; as for the mice in group ROE,SREBP-1c protein expression, FAS mRNA and FAS protein expression had no significant change （P〉0.05）; comparingthe mice in group RAE with the mice in group ROE, SREBP-1c, FAS mRNA and protein expression decreasedsignificantly （P〈0.01）. The said findings indicate the followings： RBP4 significantly increased mouseliver’s SREBP-1c gene and protein expressions, activated SREBP-1c signal pathway, and promoted liver fat synthesis;8-week aerobic exercise restrained the role of RBP4 in promoting fat synthesis in the liver, improved fat metabolism;the mechanism involved with reducing RBP4 level, reducing liver SREBP-1c gene and protein expres-sions, restraining SREBP-1c signal pathway activation, and reducing the liver’s fat synthesis function.