黑米对高脂膳食饲喂雄性小鼠抗氧化相关基因的调控

The regulation of black rice on antioxidative gene expressions in male mice

目的:研究黑米对高脂喂养小鼠血清、肝脏和脑组织抗氧化水平以及肝脏抗氧化相关基因表达的影响。方法以喂养高脂高胆固醇膳食的雄性C57BL/6J小鼠为动物模型随机分为四组,每组12只,以高脂高胆固醇膳食组为对照组(C组,52.6 g玉米淀粉/100 g粮)、三个实验组分别在小鼠高脂饲料中补充白米(C+W组,52.6 g白米/100 g粮)和黑米(C+BL,26.3 g黑米/100 g粮和C+BH,52.6 g黑米/100 g粮)。8周后收集血液及组织进行检测,测定血清、肝脏和脑组织中总超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)和丙二醛含量(MDA)水平以及肝脏抗氧化相关基因SOD、CAT、GSH-Px、HO-1、NF2L2等的mRNA表达。结果:白米组(C+W)血清、肝脏及脑中SOD、GSH-Px、CAT活性和MDA含量较高脂对照组无统计学差异,C+BL组(P<0.05)和C+BH组(P<0.01)血清中SOD酶活力较对照组升高,且C+BH组MDA含量显著降低(P<0.05);与高脂组相比,黑米实验组(C+BL和C+BH)肝脏中SOD酶活性显著升高(P<0.05),C+BH组MDA含量显著降低(P<0.05);C+BH组脑中GSH-Px酶活性与高脂组相比显著升高(P<0.05),C+BL组(P<0.05)和C+BH组(P<0.01)脑中SOD酶活较对照组升高,C+BH组MDA含量显著降低(P<0.05)。RT-PCR结果显示,与高脂组相比,黑米添加组(C+BL和C+BH)SOD2、CAT mRNA表达极显著上调(P<0.01),GSH-Px mRNA表达显著上调(P<0.01),C+BH组HO-1 mRNA表达水平显著升高(P<0.05)。结论:高脂膳食造成氧化应激,黑米膳食干预抗氧化可能是增加抗氧化酶的表达来减少氧化损伤。

Objective： The influence of black rice on antioxidant activity （SOD, GSH -Px, CAT, MDA） in serum,liver and brain and hepatic antioxidant -related genes （SOD, CAT, GSH- Px, HO- 1, NF2L2） expression which were induced by high fat and cholesterol diet （HFHC） was investigated. Method Male C57BL/6J mice （n = 48） were divided into four groups. They were fed with a HFHC diet （C group, n = 12）, composed with 52. 6 g corn starch/100 g diet or with white rice （C ＋ W group, n = 12）, 26. 3 g black rice/100 g diet （C＋BL group, n = 12） or 52.6 g black rice/100 g diet （C ＋BH group, n = 12） for 8 weeks. SOD, GSH -Px, CAT, MDA levels in serum, liver and brain were assayed by kits. The mRNA expression levels of hepatic SOD, CAT, GSH - Px, HO - 1, NF2L2 were detected with real - time PCR. Results ： The activities of serum SOD, GSH - Px, CAT and MDA content in C ＋ W group were similar with that of the control. However, SOD activity in C ＋ BL group （P 〈 0. 05） and C ＋ BH group （P 〈 0. 01 ） were significantly ele- vated than the control and the MDA content in C ＋ BH group was significantly declined （P 〈 0. 05. Hepatic SOD activity was increased in C ＋ BL and C ＋ BH group （ P 〈 0. 05, while MDA content was decreased （ P 〈 0. 05 ） in C ＋ BH group compared with that of control group. In brain, compared with control group, the activity of GSH - Px in C ＋ BH group （P 〈 0. 05） and SOD in C ＋ BL group （P 〈 0. 05 ）, C ＋ BH group （ P 〈 0. 01 ） were significantly increased, while the MDA content in C ＋ BH group was significantly declined （P 〈 0. 05 ）. The hepatic SOD2, CAT mRNA expression level （P 〈0. 01 ） and GPX- 1 mRNA （P 〈0. 05） expression level were significantly up -regulated with back rice group com- pared with that of C groups, The expression level of HO - 1 mRNA was up - regulated in C ＋ BH （P 〈 0. 05） group. Conclusion ： Black rice could attenuate oxidative stress by up - regulated the expression of related antioxidant en- zyme to inhibit oxidative damage caused by high fat diet.