蚕蛹油对高脂高糖诱导大鼠脂肪性肝炎的治疗作用研究

Effect of chrysalis oil on high-fat and high-sucrose-induced steatohepatitis in rats

目的:观察蚕蛹油对高脂高糖诱发脂肪性肝炎的治疗作用,并探讨其可能的机制。方法:雄性清洁级SD大鼠随机分为正常组、模型组、蚕蛹油1.8mg/kg组,蚕蛹油3.6mg/kg组和阳性药罗格列酮4mg/kg组。在用高脂高糖乳剂造成脂肪性肝炎后,给药组大鼠分别灌服蚕蛹油或罗格列酮,连续4周,然后取血测定大鼠血清总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)、谷丙转氨酶(ALT)和谷草转氨酶(AST)含量,取肝组织称重并计算肝重系数,同时测定肝组织中TC、TG和还原型谷胱甘肽(GSH)含量以及超氧化物歧化酶(SOD)的活性,光镜检查肝组织的形态学改变。另外,采用RT-PCR法测定肝组织中肿瘤坏死因子(TNF)α和过氧化物酶体增生物激活受体(PPAR)γmRNA表达。结果:脂肪性肝炎大鼠给予蚕蛹油1.8mg/kg和3.6mg/kg治疗4周后,对血中TC、TG、FFA和ALT含量有明显的降低作用,蚕蛹油3.6mg/kg组对肝组织中的TG含量也有降低作用,但未见对肝组织中TC含量有明显的影响。与模型组比较,蚕蛹油组的血清AST含量,以及肝重系数和肝中SOD活性未见有明显的改变,但蚕蛹油3.6mg/kg能明显增加大鼠肝组织中的GSH含量。光镜下可见,给予蚕蛹油治疗后的大鼠肝脏脂质空泡有一定的改善作用,而炎性细胞的浸润则明显减少,尤以蚕蛹油3.6mg/kg组的作用更好。另外,RT-PCR实验结果显示,蚕蛹油能够明显降低高脂饮食大鼠肝组织TNF-αmRNA表达,而同时增加PPARγmRNA表达。结论:蚕蛹油能治疗高脂高糖诱导的大鼠脂肪性肝炎,其作用机制可能与调节脂代谢,抗氧化,以及通过增加PPARγ表达而降低炎性细胞因子TNF-α表达有关。

Aim ：To investigate the therapeutic effect of chrysalis oil on high-fat and high-sucrose-induced steatohepatitis in rats and its possible mechanisms.Methods： Male Sprague-Dawley rats were randomly divided into normal group,model group,chrysalis oil 1.8mg/kg,chrysalis oil 3.6mg/kg groups and rosiglitazone 4mg/kg group.After the rat model of steatohepatitis was induced successfully,the rats in medicine-treated groups were orally given chrysalis oil or rosiglitazone by gavage for 4 weeks,respectively.Then the serum total cholesterol（TC）,triglyceride（TG）,free fatty acid（FFA）,alanine aminotransferase（ALT） and aspartate aminotransferase（AST） levels were determined by colorimetric methods,respectively.The rat liver was taken and weighed to get the hepatic weight coefficient,the contents of TC,TG,reduced glutathione hormone（GSH） as well as the activity of superoxide dismutase（SOD） in hepatic tissue were also determined simultaneously.The hepatic histological change was examined with light microscope.In addition,we used RT-PCR method to detect the mRNA expressions of tumor necrosis factor（TNF） α and peroxisome proliferator-activated receptor（PPAR） γ.Results： After rats were treated with chrysalis oil 1.8mg/kg and 3.6mg/kg for 4 weeks,the serum TC,TG,FFA and ALT levels were significantly lowered（P0.05 or P0.01）,the hepatic TG content in chrysalis oil 3.6mg/kg group was also decreased obviously（P0.05）,but hepatic TC content had no obviously change.Compared with model group,the serum AST,hepatic weight coefficient and SOD activity had not significant changes,but liver GSH content was obviously increased by chrysalis oil 3.6mg/kg treatment（P0.05）.Hepatic histological results showed that,after treatment with chrysalis oil,the amounts of hepatic lipid vacuoles and inflammatory cells were reduced,especially for inflammatory cells in chrysalis oil 3.6mg/kg group（P0.01）.In addition,RT-PCR results showed that the mRNA expression of TNF-α in rat liver induced by high fat diet was decreased,and PPAR γ mRNA expression was increased simultaneously.Conclusion ： Chrysalis oil had therapeutic effect on high-fat and high-sucrose-induced steatohepatitis in rats,and its mechanisms might be related to improving the lipid metabolism,anti-oxidation,as well as increase the expression of PPARγ and decrease inflammatory cytokines TNF-α expression.