迷迭香提取物对高脂膳食喂饲仓鼠Nrf2及下游抗氧化基因的调控

MODULATION OF ROSEMARY EXTRACT ON EXPRESSION OF Nrf2 AND ITS DOWNSTREAM ANTIOXIDANT GENES IN HIGH FAT FED HAMSTERS

目的研究迷迭香提取物对高脂膳食喂饲仓鼠体内重要抗氧化途径中转录因子Nrf2及下游抗氧化基因的调控作用。方法 50只仓鼠随机分为五组,分别为normal、HF和迷迭香膳食干预组(0.1%、0.3%及0.9%迷迭香提取物),测定血清、脑及肝脏中抗氧化酶活力及氧化产物含量,Real-time PCR法检测肝脏中抗氧化酶mRNA的表达水平。结果血清、肝脏和脑中抗氧化酶活,HF组较normal组下降,MDA含量较normal组显著升高。给予迷迭香提取物膳食干预后,血清及肝脏中SOD、CAT、GSH-Px酶活力较HF组升高,MDA含量较HF组降低。RT-PCR检测显示,HF组转录因子Nrf2 mRNA表达水平较normal组极显著升高(P<0.01),干预后Nrf2 mRNA转录水平较HF组升高(P>0.05);HF组抗氧化酶CAT、CuZn-SOD和谷胱甘肽S转移酶(GST)基因表达水平较normal组表达显著降低(P<0.05),干预后,抗氧化酶CuZn-SOD、Mn-SOD、CAT、GSH-Px和GST mRNA表达水平较HF组极显著升高(P<0.01)。结论迷迭香膳食干预高脂喂饲仓鼠抗氧化可能是更大程度激活Nrf2,增加抗氧化酶的表达并减少其损伤,达到保护机体作用。

Objective To investigate the effects of rosemary extract on expression of Nrf2 and its downstream antioxidant genes in hamsters fed high fat （HF）diet. Methods Fifty hamsters were divided randomly into five groups （normal, HF, 0.1%, 0.3%, 0.9% rosemary extract experimental groups）. The activity of SOD, CAT, GSH-Px and content of MDA in serum, brain and liver were examined. Expression of Nrf2 and antioxidant enzymes in liver were detected by RT-PCR. Results The activities of SOD, GSH-Px, CAT in serum, brain, liver were reduced ,while the content of MDA was significantly higher in HF group compared with those in normal hamsters. The activities of serum, liver SOD, GSH-Px of experimental groups supplemented with rosemary extract were increased while the content of MDA was reduced compared with those in HF group. The results of RT-PCR showed that liver mRNA expression of Nrf2 in HF group was significantly increased （P〈0.01） while the mRNA of CuZn-SOD, GSH-Px, CAT and glutathione S-transferase （GST） were reduced in HF group compared with those in normal group. The mRNA expressions of CuZn-SOD, Mn-SOD, CAT, GSH-Px and GST in groups supplemented with rosemary extract were significantly elevated compared with those in HF group （P〈0.01）. Conclusion The antioxidant activity of rosemary extract is involved in activating Nrf2 signal pathway, up-regulating the expression of antioxidant protein and reducing the damage of some enzymes in hamsters fed HF diet.