褪黑素对热应激奶牛乳腺上皮细胞及育成牛血清HSP70含量的影响  

Effect of melatonin on dairy cow mammary epithelial cells and serum HSP70 of bred cattle under heat stress

作　　者：史素荣[1] 宋志恒 周亚星 张桂枝[1] 刘太宇[1] 刘亚红[1] SHI Surong;SONG Zhiheng;ZHOU Yaxing;ZHANG Guizhi;LIU Taiyu;LIU Yahong(Henan Province International Joint Laboratory of Ruminant Nutrition and Feed Resource Development,Henan University of Animal Husbandry and Economy,Zhengzhou 450046,China;College of Veterinary Medicine,Henan Agricultural University,Zhengzhou 450046,China)

机构地区：[1]河南牧业经济学院河南省反刍动物营养与饲料资源开发国际联合实验室,郑州450046 [2]河南农业大学动物医学院,郑州450046

出　　处：《黑龙江畜牧兽医》2022年第15期68-73,共6页Heilongjiang Animal Science And veterinary Medicine

基　　金：河南省重大科技专项计划项目(161100510200)。

摘　　要：为了研究褪黑素(MLT)对热应激奶牛乳腺上皮细胞(MAC-T)及中国荷斯坦育成牛血清中热休克蛋白70(HSP70)含量的影响,试验将体外培养的MAC-T分为对照组、热应激组、热应激+150μmol/L MLT组,以42℃作为热应激模型温度,37℃作为对照组培养温度,采用细胞增殖法检测细胞活力、实时荧光定量PCR检测细胞凋亡因子半胱氨酸蛋白酶3(Caspase-3),炎性因子IL-6、IL-8和HSP70 mRNA相对表达量;以处于热应激状态的中国荷斯坦育成牛为试验动物,随机分为对照组、试验A组、试验B组,分别皮下注射0,4.6,46 mg/d MLT,采用ELISA试剂盒测定奶牛血清中HSP70含量。结果表明:热应激处理4 h的MAC-T细胞活力与对照组相比显著降低(P<0.05),添加150μmol/L MLT可以显著升高MAC-T细胞活力(P<0.05);与对照组比较,热应激可以极显著上调MAC-T细胞凋亡因子Caspase-3和HSP70 mRNA的相对表达量(P<0.01),显著上调炎性因子IL-6、IL-8的相对表达量(P<0.05);与热应激组比较,添加150μmol/L MLT可以极显著上调HSP70 mRNA的相对表达量(P<0.01),极显著下调细胞凋亡因子Caspase-3(P<0.01)及显著下调炎性因子IL-6、IL-8(P<0.05)的相对表达量;皮下注射46 mg/d MLT可显著提升热应激育成牛第6天血清HSP70的含量(P<0.05)。说明MLT可以提高热应激MAC-T的应激耐受性,减少炎性损伤和细胞凋亡;皮下注射46 mg/d MLT可以提高育成牛的热应激耐受性,有利于高温环境中维持自身内环境的稳定。In order to study the effect of melatonin(MLT)on dairy cow mammary epithelial cells MAC-T and serum HSP70 content of Holstein bred cattle under heat stress,in this experiment the MAC-T cultured in vitro were divided into control group,heat stress group and heat stress+150μmol/L MLT group.With 42℃as the heat stress model temperature and 37℃as the control group culture temperature,the cell proliferation method was used to detect the cell viability,and the real-time fluorescence quantitative PCR was used to detect the relative mRNA expression of apoptosis factor Caspase-3,inflammatory factors IL-6,IL-8 and HSP70.Holstein bred cattle under heat stress were used as test animals,and were randomly divided into control group,test group A,and test group B,which were given 0,4.6,46 mg/d MLT respectively by subcutaneous injection.The content of HSP70 in cow serum was determined by ELISA kit.The results showed that the vitality of MAC-T cells treated with heat stress for 4 h was significantly lower than that of the control group(P<0.05);adding 150μmol/L MLT could significantly increase the vitality of MAC-T cells(P<0.05).Compared with the control group,heat stress could very significantly up-regulate the relative expression of Caspase-3 and HSP70 mRNA in MAC-T cells(P<0.01),and significantly up-regulate the relative expression of inflammatory factors IL-6 and IL-8(P<0.05).Compared with the heat stress group,the addition of 150μmol/L MLT could very significantly up-regulate the relative expression of HSP70 mRNA(P<0.01),very significantly down-regulate the relative expression of apoptosis factor Caspase-3(P<0.01)and significantly down-regulate the relative expression of inflammatory factors IL-6 and IL-8(P<0.05).Subcutaneous injection of 46 mg/d MLT could significantly increase the content of HSP70 in the serum of bred cattle under heat stress on the 6th day(P<0.05).The results suggested that MLT could improve the stress tolerance of heat-stressed MAC-T cells,reduce inflammatory damage and apoptosis.Subcutaneous injecti

关 键 词：褪黑素 热应激 MAC-T细胞 荷斯坦育成牛 热休克蛋白70 

分 类 号：S823[农业科学—畜牧学]