二氧化硫对高脂饲养大鼠肝组织胆固醇水平的影响

目的探讨二氧化硫(SO_2)对高脂饲养大鼠肝组织胆固醇水平的影响。方法雄性SD大鼠28只,随机分为对照组(8只)、高脂组(10只)和SO_2组(10只)。留取肝组织冷冻切片,分别进行油红O染色、总胆固醇Philipin荧光染色、HE染色,并对油红O染色和总胆固醇染色结果进行图像分析。结果油红O染色显示,对照组肝组织学形态大致正常;高脂组肝细胞内、细胞间隙脂质呈弥漫沉积,肝小叶结构受损;SO_2组脂质沉积较高脂组明显减少(P0.01),肝小叶结构受损程度减轻。总胆固醇Philipin荧光染色显示,对照组无阳性信号;高脂组荧光阳性信号强烈,且满视野,分布较均匀;SO_2组阳性信号荧光强度较高脂组明显减弱(P0.01)。HE染色显示,对照组肝细胞形态正常;高脂组肝细胞含较大脂滴,肿大变圆,小叶中央区受累明显,肝细胞排列紊乱;SO_2组肝细胞内脂滴明显减少,肝细胞形态有所恢复,病变程度减轻。结论大鼠高脂饮食导致肝脏脂质代谢明显异常;外源性SO_2对大鼠高脂饮食所致肝脏脂质代谢有明显改善作用;推测该作用可能是其减轻动脉粥样硬化的机制之一。

Effects of sulfur dioxide on hepatic cholesterol metabolism in high-fat-fed rat

Objective To investigate the effects of sulfur dioxide on hepatic cholesterol metabolism in high-fat-fed rats.Methods Twenty-eight male SD rats were divided into three groups randomly: normal control(C) group (n = 8);high-fat-fed(H-FD) group (n = 10);and SO_2 group (n = 10).The hepatic tissue was cut into frozen sections,which were stained by oil red O stain,Philipin stain and HE stain respectively.The pictures of sections stained by oil red O stain and Philipin stain were analyzed.Results Compared with group C,in group H-FD,oil red O staining showed that lipidosis was distributed diffusely and structure of hepatic lobules was damaged in the liver of rats,and Philipin staining showed that total cholesterol fluorescence signal was strongly positive. Compared with group H-FD,in SO_2-treated rats,lipidosis reduced significantly in the liver,and Philipin staining showed that total cholesterol fluorescence intensity decreased obviously (P < 0.01).Compared with group C,HE staining showed that in rats of H-FD group,hepatocytes contained big lipid droplets,and their shape turned to be swollen and round.The pathological changes were more obvious in the central area of hepatic lobules and the hepatocytes were misarranged. Compared with group H-FD,in SO_2-treated rats,the lipid droplets in the hepatocytes decreased distinctly,the shape of hepatocytes recovered and pathological changes were ameliorated.Conclusions Exogenous SO_2 plays a role in lipid metabolism of liver in atherosclerosis,indicating that SO_2 might have alleviating effect on atherosclerosis.