摘要
本试验旨在探讨褪黑素(MT)对脂多糖(LPS)诱导的奶牛乳腺上皮细胞(BMECs)炎症反应的缓解作用及潜在机制。利用不同浓度(0.1、0.5、1.0、5.0和10.0μg/mL)的LPS处理BMECs 6和12 h后,通过测定BMECs活性和炎性细胞因子[肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)]含量,确定10μg/mL的LPS诱导12 h用于正式试验。正式试验共设7组,每组设4个重复。对照组BMECs不进行LPS诱导和MT处理,LPS组BMECs进行LPS诱导12 h,LPS+MT组BMECs进行LPS诱导12 h后再经不同浓度(1、5、10、50和100μmol/L)MT处理48 h。结果表明:1)与对照组相比,LPS组BMECs中TNF-α含量升高(P>0.05),BMECs中IL-6和IL-1β含量显著升高(P<0.05)。与LPS组相比,10和50μmol/L MT组BMECs中TNF-α含量显著降低(P<0.05),1、5、10和100μmol/L MT组BMECs中IL-6含量显著降低(P<0.05),10μmol/L MT组BMECs中IL-1β含量显著降低(P<0.05)。2)与对照组相比,LPS组BMECs中Toll样受体4(TLR4)蛋白表达量升高(P>0.05),BMECs中核因子-κB同源蛋白(P65)和核因子-κB抑制蛋白-α(IκB-α)蛋白表达量显著降低(P<0.05)。与LPS组相比,50和100μmol/L MT组BMECs中TLR4蛋白表达量显著降低(P<0.05),1、10和50μmol/L MT组BMECs中P65蛋白表达量显著或极显著升高(P<0.05或P<0.01),1、5、10和50μmol/L MT组BMECs中IκB-α蛋白表达量显著或极显著升高(P<0.05或P<0.01)。由此可见,MT能够降低LPS诱导的BMECs中TNF-α、IL-1β和IL-6含量,调控LPS诱导的BMECs中TLR4、P65和IκB-α蛋白表达量,MT可能通过参与核因子-κB炎症通路缓解LPS诱导的BMECs炎症反应。
The purpose of this study was to investigate the mitigative effects and underlying mechanisms of melatonin(MT)on lipopolysaccharide(LPS)-induced inflammation in bovine mammary epithelial cells(BMECs).The BMECs were treated with different concentrations(0.1,0.5,1.0,5.0 and 10.0μg/mL)of LPS for 6 and 12 hours,respectively.The BMECs viability was detected and the inflammatory cytokines[tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and interleukin-6(IL-6)]contents was measured,and the BMECs model was established with 12 hours and 10μg/mL LPS for formal experiment.The formal experiment divided into 7 groups with 4 replicates in each group.BMECs in the control group without LPS-induced and MT treated,BMECs in the LPS group were LPS-induced 12 hours,and BMECs in LPS+MT groups were LPS-induced 12 hours and treated with different concentrations(1,5,10,50 and 100μmol/L)of LPS for 48 hours,respectively.The results showed as follows:1)compared with the control group,the BMECs TNF-αcontent of LPS group was increased(P>0.05),and the contents of IL-6 and IL-1βin BMECs were significantly increased(P<0.05).Compared with the LPS group,the BMECs TNF-αcontent of 10 and 50μmol/L MT groups was significantly decreased(P<0.05),the BMECs IL-6 content of 1,5,10 and 100μmol/L MT groups was significantly decreased(P<0.05),and the BMECs IL-1βcontent of 10μmol/L MT group was significantly decreased(P<0.05).2)Compared with the control group,the BMECs Toll-like receptor 4(TLR4)protein expression level of LPS group was increased(P>0.05),and the protein expression levels of nuclear factor-κB homologous protein(P65)and nuclear factor-κB inhibitory protein-α(IκB-α)in BMECs were significantly decreased(P<0.05).Compared with the LPS group,the BMECs TLR4 protein expression level of 10 and 100μmol/L MT groups was significantly decreased(P<0.05),the BMECs P65 protein expression level of 1,10 and 50μmol/L MT groups was significantly increased(P<0.05 or P<0.01),and the BMECs IκB-αprotein expression level of 1,5,10 and 50μmol/L MT group was significantly increased(P<0.05 or P<0.01).It is concluded that MT can reduce the contents of TNF-α,IL-1βand IL-6 in BMECs induced by LPS,regulate the protein expression levels of TLR4,P65 and IκB-αin BMECs induced by LPS,and likely participate nuclear factor-κB inflammatory pathway,which exerted anti-inflammatory effect in LPS-challenged BMECs.
作者
李洪洋
南雪梅
孙鹏
LI Hongyang;NAN Xuemei;SUN Peng(State Key Laboratory of Animal Nutrition,Institute of Animal Sciences,Chinese Academy of Agricultural Sciences,Beijing 100193,China)
出处
《动物营养学报》
CAS
CSCD
北大核心
2021年第8期4637-4644,共8页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家重点研发计划(2016YFD0500507)
中国农业科学院科技创新工程(ASTIP-IAS07)。
关键词
乳房炎
褪黑素
脂多糖
抗炎
炎症通路
mastitis
melatonin
lipopolysaccharide
anti-inflammatory
inflammatory pathway
