甘露糖加重ApoE缺陷小鼠的脂蛋白代谢紊乱

目的：探讨甘露糖暴露对载脂蛋白E(ApoE)缺陷小鼠高脂血症的影响及其机制。方法：6周龄雄性ApoE基因敲除小鼠在西方饮食同时给与2%甘露糖饮水4周。酶法检测血浆总胆固醇及甘油三酯水平,利用快速蛋白液相色谱分离血浆脂蛋白,并检测分析载脂蛋白和胆固醇水平的变化。利用RT-PCR和Western蛋白印迹,分别检测分析肝脏和空肠组织中脂蛋白代谢相关基因的mRNA和蛋白表达水平。结果：甘露糖饮水可显著升高ApoE缺陷小鼠的血浆总胆固醇和甘油三酯水平,同时伴有极低密度脂蛋白(VLDL)中胆固醇含量和载脂蛋白B100(ApoB100)蛋白水平显著升高、高密度脂蛋白(HDL)中载脂蛋白A1(ApoA1)和载脂蛋白A4(ApoA4)水平降低。血中ApoA1和ApoA4水平下调的机制与肝脏和空肠组织中的蛋白表达水平降低有关。结论：甘露糖暴露可影响ApoE缺陷小鼠的脂蛋白代谢,加重高脂血症。

Mannose aggravates lipoprotein metabolism disorder in ApoE deficient mice

Objective: To investigate the effect and mechanism of mannose exposure on the hyperlipidemia in apolipoprotein E(ApoE)-deficient mice. METHODS: ApoE-deficient mice (6 weeks old, male) were fed the Western diet for 4 weeks with or without 2% mannose (w/v) in drinking water. Plasma total cholesterol and triglyceride concentrations were measured by the enzymatic methods. Plasma lipoproteins were separated by fast protein liquid chromatography, and the fractional apolipoprotein and cholesterol levels of which were measured. The mRNA and protein expression levels of lipoprotein metabolism-related genes in the liver and jejunum were detected by RT-PCR and Western blotting. RESULTS: Mannose drinking water significantly increases the plasma total cholesterol and triglyceride levels in ApoE-deficient mice. Meanwhile, mannose increases the cholesterol levels and ApoB100 levels in VLDL and decreases the levels of ApoA1 and ApoA4 in HDL. The reduction of plasma ApoA1 and ApoA4 levels is related to their decreased protein expression in the liver and jejunum. CONCLUSION: Mannose exposure affects lipoprotein metabolism and aggravates hyperlipidemia in ApoE-deficient mice.