维生素K对去卵巢大鼠肝氧化应激及炎症因子的影响

Effects of phylloquinone on hepatic oxidative stress and inflammatory factors in ovariectomized rats

目的:探讨补充维生素K对去卵巢大鼠肝氧化应激及炎症的影响。方法:以去卵巢SD大鼠作为围绝经期模型,比较维生素K补充与不补充对肝组织丙二醛,超氧化物歧化酶(SOD),还原型谷胱甘肽(GSH)等氧化应激指标以及肿瘤坏死因子α(TNF-α)和白介素6(IL-6)的影响。将30只6月龄雌性SD大鼠随机分为3组,每组均为10只,即假手术组,去卵巢组以及去卵巢后补充维生素K组(维生素K组)。术后1周开始分组给药,维生素K组将维生素K混于丙三醇中每日灌胃,而假手术组和去卵巢组每日给予丙三醇灌胃。90 d后,取肝组织测定丙二醛,SOD,GSH;冰冻切片行苏木素-伊红(HE)与活性氧(ROS)荧光染色;免疫印迹检测TNF-α和IL-6的表达。结果:维生素K组肝组织丙二醛水平较去卵巢组明显降低,但明显高于假手术组(P均<0.05)。维生素K组肝组织SOD,GSH水平均较去卵巢组明显降低(P<0.05),与假手术组比较差异无统计学意义。形态学检测表明维生素K组肝细胞胞质内小空泡数目明显少于去卵巢组,而假手术组则未见空泡;维生素K组肝细胞内活性氧荧光强度明显低于去卵巢组,与假手术组相近。免疫印迹结果表明维生素K组肝内TNF-α与IL-6表达水平均介于去卵巢组和假手术组之间;去卵巢组两种因子水平明显高于假手术组。结论:去卵巢大鼠肝组织处于较高的氧化应激状态,并伴有促炎因子表达增高,这种改变能在一定程度上被维生素K缓解。

Objective： To observe the effects of phylloquinone supplementation on hepatic oxidative stress and inflammation in ovariectomized rats and to propose a new way to prevent the hepatic impairment associated with menopause. Methods ： Thirty female SD rats of six months age were randomly divided into 3 groups, sham group （Sham, n = 10）, ovariectomy group （OVX, n = 10）, phylloquinone supplementation after ovariectomy group （OVX ＋ VK, n = 10）. One week after operation, phylloquinone or glycerol which served as delivery agent was administrated through gastric lavage to OVK ＋ VK group or Sham and OVX group respectively for 90 days. After that, the livers were harvested to determine malonaldehyde （MDA） , superoxide dismutase （ SOD ） and glutathione （ GSH ） levels. Hematoxylin eosin （ HE ） and reactive oxygen species （ROS） fluorescent staining were performed on hepatic frozen sections. The expressions of IL-6 and TNF-α in the livers were evaluated by Western blotting. Results： The hepatic MDA levels in the OVX ＋ VK group were significantly lower than those in the OVX group and higher than those in the Sham group （ both P 〈 0. 05 ）. The hepatic SOD and GSH levels in the OVX ＋ VK group were significantly lower than those in the OVX group, but were not significantly different from those in the Sham group. HE staining demonstrated that the small vacuoles in the OVX ＋ VK group were obviously fewer than those in the OVX group while the livers in Sham group contained no vacuole. The ROS fluorescence in the hepatic sections in the OVX ＋ VK group was weaker than that in the OVX group. The results of Western blotting demonstrated that the levels of IL-6 and TNF-ot in the OVX ＋ VK group located between the other two groups while those in the OVX group were higher than those in the Sham group. Conclusion： The liver of ovariectomized rats was under higher oxidative stress concomitant with higher levels of inflammatory factors as compared with that of normal rats. These changes can be alleviated by phylloquinone supplementation to some extents.