IL-18对大鼠非酒精性脂肪肝病形成的作用

目的: 分析在高脂饮食诱发大鼠非酒精性脂肪肝病(NAFLD)形成过程中胰岛素抵抗(IR)与IL-18之间的相关性,并探讨IL-18对大鼠NAFLD形成的作用.方法: 将48只♂SD大鼠随机分为正常饮食组(NG)及高脂饮食组(FG),各24只,喂养至第2、4、6、8周末时,2组各随机抽取6只,抽取门静脉血测空腹血糖(FBS)、空腹胰岛素(FINS),计算空腹胰岛素抵抗指数(FIRI);检测血清及肝组织匀浆IL-18浓度;光镜检查肝组织切片以评价肝脏脂肪变性程度.结果: FG第4周末开始出现IR,血清及肝组织匀浆IL-18均随喂养时间的延长逐渐升高,各期均高于NG,肝组织匀浆IL-18在第2、4、6、8周末均与同期NG比较均有统计学差异均P<0.05),而血清IL-18是第4、6、8周末与同期NG比较均有统计学差异(均P<0.05). FINS、FIRI、血清及肝组织匀浆IL-18均与肝脂肪变性呈正相关( r = 0.951,0.971,0.950,0.937,均P<0.05). 血清IL-18与FINS、FIRI及肝组织匀浆IL-18与FINS、FIRI均成正相关( r = 0.951,0.933,0.929,0.913,均P<0.05).结论: IR在高脂饮食诱发的NAFLD的发生发展中有重要作用,IL-18与IR形成有关,并与NAFLD的形成相关联.

Effect of interleukin-18 on nonalcoholic fatty liver disease in rats

AIM: To analyze the relationship between rats' degree of insulin resistance and the concentration of IL-18 during the process of developing nonalcoholic fatty liver disease (NAFLD) by feeding a fat-rich diet,and to discuss the effect of IL-18 on NAFLD in rats. METHODS: Forty-eight male SD rats were randomly divided into a normal diet group (NG) and a fat-rich diet group (FG),and there were 24 rats in each group. At the end of feeding for 2,4,6 and 8 wk,6 rats in each group were randomly selected,the serum fasting blood sugar (FBS),fasting insulin (FINS) and the fasting insulin resistance index (FIRI),and the concentration of IL-18 in serum and liver tissue serosity were measured. Hepatic steatosis in all rats was scored according to criteria under light microscopy. RESULTS: All FG rats had a significant elevated level of serum FINS,FIRI from the fourth weekend;The concentration of liver IL-18 and serum IL-18 of rats in FG was increasing gradually,in comparison with the NG,there was a difference in liver IL-18 of FG from the second weekend and serum IL-18 from the fourth weekend (all P < 0.05). FINS,FIRI and IL-18 were all positively correlated with hepatic steatosis in FG (r = 0.951,0.971,0.950,0.937,all P < 0.05). Serum IL-18and FINS,serum IL-18 and FIRI,liver IL-18 and FINS,liver IL-18 and FIRI all had positive relationship (r = 0.951,0.933,0.929,0.913,all P < 0.05).CONCLUSION: IR may play an important role in the development of NAFLD by feeding rats fat-rich diet,and IL-18 may participate in the pathogenesis of NAFLD possibly through with a link to IR.