高剂量摄入鱼油导致大鼠脂肪肝的实验研究

Experimental study of high-dosage intake of fish oil inducing fatty livers in SD rats

目的分析低剂量、高剂量鱼油对大鼠血脂、肝脏脂肪沉积及胰岛素敏感性的影响。方法 24只雄性SD大鼠随机分为3组,对照组(NC)、低剂量鱼油组(LFO)、高剂量鱼油组(HFO)。喂养12周,记录采食量及体重,测定血清甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、游离脂肪酸(FFA),分析肝脏脂肪沉积及胰岛素敏感性。数据采用单因素方差分析,P<0.05为差异有统计学意义。结果 LFO、HFO组血清TG、TC均低于NC组,差异有统计学意义(P<0.05),3组间HDL-C、FFA差异无统计学意义(P>0.05);LFO及NC组肝脏结构正常,肝细胞索排列紧密,肝细胞内未见脂肪沉积,而HFO组肝细胞内有大量脂肪聚集,为严重脂肪肝;3组大鼠胰岛素敏感性差异无统计学意义(P=0.086)。结论低剂量、高剂量摄入鱼油均能降低大鼠血脂,但高剂量摄入导致大鼠脂肪肝。

Objective To study the effect of high-dosage fish oil intake on blood lipid level,fat deposit in liver and insulin sensitivity in SD rats. Methods Twenty-four healthy male SD rats were randomly divided into 3groups,and were treated with nothing as normal controls（NC）,low-dosage fish oil（LFO）or high-dosage of fish oil（HFO）for 12 weeks.Blood samples were collected to measure serum levels of lipid（TG）,total cholesterol（TC）,HDL-C,FFA,glucose（GLU）,and insulin（INS）.Fat deposits in the livers were evaluated by oil red staining.The insulin sensitivity was determined by ISI index.Data was analyzed using one-way ANOVA.Results Serum levels of TG and TC in rats treated with both LFO and HFO were significantly lower than those of NC rats（P〈0.05）,while,HDL and FFA levels were close（P〉0.05）.Hepatic pathological analysis revealed an abnormal morphology of liver with heavy fat deposit in rats treated with HFO,while,the liver structure remained normal in other rats.There were no significant differences of insulin sensitivity among rats in three groups（P=0.086）. Conclusions Even though both low and high dosage fish oil intake may significantly lower serum lipid level,but excessive intake of fish oil induces fatty liver in rats.