甜菜碱对老龄db/db小鼠脂肪性肝损害的影响

 目的：通过高脂饮食诱发db/db小鼠非酒精性脂肪性肝病（NAFLD）模型，探索甜菜碱对遗传性小鼠脂肪肝脂质代谢的影响。方法：50只7月龄db/db鼠随机分为低、中、高剂量组、生理盐水对照组和阳性药物组。所有小鼠均饲以高脂饲料, 以诱发NAFLD 模型。 小鼠分别以200 mg/kg(低剂量组)、400 mg/kg(中剂量组)和800 mg/kg(高剂量组)甜菜碱溶液灌胃，连续6周。测定血清丙氨酸氨基转移酶(ALT)、甘油三酯(TG)、总胆固醇（TC）和低密度脂蛋白(LDL)水平，并行葡萄糖耐量测定和肝组织病理学观察。结果：甜菜碱可显著降低血清ALT、TC和LDL的水平(P<0.05或P<0.01)。组织学结果表明甜菜碱可显著减少小鼠肝细胞的脂肪样变性。结论: 甜菜碱可以显著改善老龄db/db小鼠的脂类代谢紊乱和肝功能，明显降低脂肪在肝细胞中的积蓄。

Effect of betaine on liver injuries in aging db/db mice induced by lipids

AIM: To evaluate the effect of betaine on lipid metabolism disorder in inherited db/db mice with long-term nonalcoholic fatty liver disease (NAFLD).METHODS: Experimental NAFLD models were established by feeding the db/db mice with high-fat diet. Fifty 7-month-old db/db mice were randomly divided into 5 groups: the mice in low, medium and high dose groups were given betaine by intragastric administration at doses of 200 mg/kg, 400 mg/kg and 800 mg/kg for 6 weeks, respectively,while the mice in saline control group and positive drug group were given normal saline and positive control drug,respctively. All the animals were killed, and serum alanine aminotransferase (ALT), triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL) and glucose tolerance were detected. The pathological changes of the liver tissues were also observed.RESULTS: Betaine significantly decreased the levels of ALT, TC and LDL (P<0.05 or P<0.01). The pathological changes of the liver tissues indicated that the content of lipid in the hepatocytes of betaine treatment groups was less than that in saline control group.CONCLUSION: Betaine significantly improves the lipid metabolism and the liver function in the aging db/db mice, and reduces the accumulation of lipid in the hepatocytes.