硫辛酸对高脂饮食小鼠肠道氧化还原状态及消化吸收功能的影响

Effect of lipoic acid on redox regulation,digestive and absorptive function in intestine of mice fed high fat diet

目的:探讨抗氧化剂硫辛酸(LA)对高脂饮食小鼠肠道氧化还原状态调节及消化吸收功能的影响。方法:24只C57BL/6雄性小鼠,随机分为3组:即对照组(正常饮食)、高脂组(高脂饮食)、LA组(高脂饮食+0.1%LA),6周后测定活性氧(ROS)、超氧化物歧化酶(SOD)、丙二醛(MDA)和总抗氧化能力(TAC)以及脂肪酶、淀粉酶、胰蛋白酶等消化酶指标,同时用Affymetrix MOE430A基因芯片分析肠道抗氧化、消化吸收相关功能基因的表达。结果:与高脂组相比,LA组MDA和ROS含量显著降低(P<0.05),SOD和TAC明显升高,消化酶活力有所恢复。抗氧化剂LA上调高脂饮食小鼠肠道抗氧化相关功能基因的表达水平,恢复物质消化、吸收和转运等相关功能基因的表达水平。结论:高脂引发氧化-抗氧化系统失衡,硫辛酸通过直接清除自由基以及提高抗氧化通路相关功能基因的表达水平解除氧化应激而有助于防治高脂引发的肠道功能损伤。

AIM ： To elucidate the molecular mechanisms of lipoic acid （LA） on redox regulation and digestive function in intestine of C57BL/6 mice fed high fat diet （HFD）. METHODS： C57BL/6 mice were randomly assigned to one of three groups （ n = 8）. The control group consumed an ordinary diet. The other two experimental groups were fed with a high fat diet, high fat plus 0.1% LA. After 6 weeks, the activities of digestive enzymes were examined. In order to evaluate the antioxidant status of the mice, superoxide dismutase （SOD）, malondialdehyde （MDA）, total antioxidant capacity （TAG） and reactive oxygen species （ROS） in intestinal homogenate were measured. To investigate the molecular mechanisms underlying the effects of LA, the gene expression profiles in intestine were examined using the GeneChip microarray system. RESULTS： A depressed antioxidant defense system, accompanied by digestive and absorptive function impairment, was observed in HFD -fed mice. These changes were partially restored in the LA -treated group. DNA microarray analysis of intestine showed that LA ingestion up - regulated the expression of genes related to free - radical scavenger enzymes, digestive enzymes and transporters. CONCLUSION： Treatment with LA improves redox homeostasis and the function of intestine in mice fed HFD. The mechanism may involve preventing oxidative stress by scavenging ROS directly and increasing those of free - radical scavenger enzymes gene expression indirectly.