辣木叶多糖对过氧化氢诱导奶牛乳腺上皮细胞氧化损伤的保护作用

奶牛乳腺上皮细胞(BMECs)在奶牛泌乳期代谢旺盛,导致活性氧(ROS)大量产生,从而诱发氧化应激。辣木叶多糖(MLP)能有效清除ROS和自由基,但其是否具有缓解BMECs氧化损伤的潜力尚不清楚。因此,本文以MLP为添加剂,探究其对过氧化氢(H2O2)诱导BMECs氧化损伤的保护作用。本试验首先将分离的BMECs置于含有不同浓度H2O2的培养基中培养2 h建立氧化损伤模型,以确定H2O2的适宜浓度;随后在培养基中加入不同浓度MLP溶液培养BMECs 2 h,以确定MLP适宜浓度;最终选用浓度为500μmol/L的H2O2和4 mg/mL的MLP用于本试验。试验设置4个组,分别为对照组1(BMECs)、对照组2(BMECs+MLP)、损伤组(BMECs+H2O2)、保护组(BMECs+MLP+H2O2),每组3个重复。试验对BMECs中ROS数量、BMECs凋亡以及BMECs中过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量进行检测。结果表明:1)ROS检测结果显示,MLP抑制了细胞内ROS的生成。2)Hochest33258染色结果与透射电镜观察结果显示,MLP降低了BMECs的凋亡率,同时保持了细胞膜和细胞结构完整性。3)试剂盒检测结果显示,MLP提高了BMECs中CAT、GSH-Px和SOD活性,同时降低了MDA含量。综上所述,MLP可有效减缓BMECs凋亡,提高其抗氧化能力。

Protective Effects of Moringa Leaf Polysaccharide on Oxidative Damage of Dairy Cow Mammary Epithelial Cells Induced by Hydrogen Peroxide

The metabolism of bovine mammary epithelial cells(BMECs)is vigorous during lactation,which leads to the production of reactive oxygen species(ROS)and the occurrence of oxidative stress.Moringa leaf polysaccharide(MLP)has the ability of scavenging active oxygen and free radicals,however,whether it has the potential to alleviate oxidative damage of mammary epithelial cells in dairy cows is still unknown.Therefore,MLP was used as an additive in this study to evaluate its protective effect on the oxidative damage of BMECs induced by hydrogen peroxide(H2O2).In this experiment,BMECs were first cultured in different concentrations of H2O2 for 2 h to establish an oxidative stress model to determine the optimal concentration of H2O2.Subsequently,BMECs were cultured in MLP solution with different concentrations for 2 h to determine the optimal concentration of MLP.Finally,H2O2 with a concentration of 500μmol/L and MLP with a concentration of 4 mg/mL were selected for the following experiments.The experiment was divided into four groups:CON1(BMECs),CON2(BMECs+H2O2),injury group(BMECs+H2O2)and protection group(BMECs+MLP+H2O2),and three repeats in each group.The number of reactive oxygen species(ROS)in BMECs,apoptosis of BMECs,catalase(CAT),glutathione peroxidase(GSH-Px),superoxide dismutase(SOD)activities and malondialdehyde(MDA)content in BMECs were detected.The results showed as follows:the results of ROS detection showed that MLP inhibited the production of ROS in cells.The results of Hochest33258 staining and transmission electron microscopy showed that MLP reduced the apoptotic rate of BMECs,meanwhile,maintaining the integrity of cell membrane and cell structure.The results of kits test showed that MLP increased the activities of CAT,GSH-Px and SOD,and decreased the content of MDA.Overall,the MLP can effectively slow down the apoptosis of mammary epithelial cells and improve their antioxidant capacity.