以高脂高胆固醇膳食饲喂仓鼠为动物模型,研究木浆源甾醇对仓鼠胆固醇调控及肠道菌群的影响.45只实验动物随机分成正常组、高脂组和3个不同剂量木浆源甾醇组(1‰、5‰、10‰).测定血清中总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)及高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)水平,应用气相色谱检测粪便固醇排泄量,应用实时荧光定量聚合酶链式反应分析小肠中胆固醇调控相关基因的表达水平,应用变性梯度凝胶电泳分析肠道菌群变化.结果显示,与高脂组相比,给予木浆源甾醇仓鼠的TC、TG和non HDL-C水平均显著降低(P＜0.05);5‰和10‰组仓鼠肝脏质量极显著降低(P＜0.01);木浆源甾醇5‰和10‰组乙酰辅酶A乙酰基转移酶-2和微粒体甘油三酯转运蛋白mRNA表达水平均显著降低(P＜0.05),10‰组羟甲基戊二酰辅酶A还原酶、三磷酸腺苷结合盒转运体G5和G8 mRNA表达水平显著提高(P＜0.05);10‰组仓鼠中性固醇和酸性固醇排泄量均极显著增加(P＜0.01);1‰和5‰剂量木浆源甾醇能显著降低由高脂高胆固醇膳食引起的肠道菌群异常增殖(P＜0.05).给予木浆源甾醇可显著降低Oscillibacter sp.、Desulfovibrio sp.等菌的数量(P＜0.05),显著增加Akkermansia sp.、Anaerostipes sp.及Roseburia sp.等菌的数量(P＜0.05).结果表明,摄入木浆源甾醇可以增加仓鼠肠道胆固醇的排泄、抑制胆固醇的合成吸收和改善肠道菌群.%The aim of this research was to investigate the effects of wood pulp-derived sterols on cholesterol regulation and the intestinal microbiota in Golden Syrian hamsters fed a high-fat and high-cholesterol diet.Totally 45 hamsters were randomly divided into normal group,high-fat and high-cholesterol (HFHC) group and three experimental groups given 1‰,5‰ and 10‰ of wood pulp-derived sterols,respectively.Serum total cholesterol (TC),triglyceride (TG) and high-density-lipoprotein-cholesterol (HDL-C) were detected in all animals.The contents of cholesterol in liver,fecal neutral and acidic sterols were determined by gas chromatography (GC).The expression of cholesterol-regulating genes in the liver and small intestine was assayed by quantitative real-time polymerase chain reaction (qRT-PCR).The change of intestinal microbiota was assayed by denaturing gradient gel electrophoresis (DGGE).TC,TG and non HDL-C in the experimental groups were significantly decreased compared with the HFHC group (P ＜ 0.05),and hepatic cholesterol level was significantly decreased with increasing dose of wood pulp-derived sterol (P ＜ 0.01).The weight of liver in the 5‰ and 10‰ groups was significantly decreased compared with the HFHC group (P ＜ 0.01).The mRNA expression levels of acyl-coenzyme A:cholesterol acyltransferase-2 (ACAT-2) and microsomal triglyceride transfer protein (MTP) in the 5‰ and 10‰ groups were significantly decreased (P ＜ 0.05),and the RNA expression levels of 3-hydroxy-3-methylglutaryl-coenzyme A reductase the ATP-binding cassette (ABC) transporters ABCG5 and ABCG8 in the 10‰ group was significantly increased (P ＜ 0.05) compared with the HFHC group.Significantly higher fecal excretion of total fecal neutral sterols and total fecal acidic sterols were observed in the 10‰ group compared with the HFHC group (P ＜ 0.01).Wood pulp-derived sterols at doses of 1‰ and 5‰ significantly decreased intestinal bacterial overgrowth induced by HFHC diet (P ＜ 0.05).Oscillibacter sp.and Desulfovibrio sp.were significantly decreased,while Akkermansia sp.,Anaerostipes sp.and Roseburia sp.were significantly increased in the experimental groups (P ＜ 0.05).Therefore,wood pulp-derived sterol resulted in increasing intestinal cholesterol excretion and inhibition of cholesterol absorption and synthesis,and improved the intestinal microbiota in hamsters.
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