热射病小鼠大脑皮层组织中炎症细胞因子水平及P38MAPK/P65NF-κB信号通路变化

Changes of inflammatory cytokine levels and P38MAPK/P65NF-κB signaling pathway in cerebral cortex tissue of mice with heat stroke

目的:探讨热射病小鼠大脑皮层组织中白细胞介素1β(IL-1β)、白细胞介素-6 (IL-6)、肿瘤坏死因子α(TNF-α)水平和P38丝裂原活化蛋白激酶(P38MAPK)/P65核转录因子κB (P65NF-κB)信号通路的变化,并阐明其机制。方法:将60只小鼠根据随机数字法分为对照组及热射病1、6和24h组(热射病模型小鼠出舱后1、6和24h),每组15只。观察各组小鼠体质量丢失和肛温,HE染色检测各组小鼠大脑皮层组织的形态表现,ELISA法测定各组小鼠大脑皮层组织中IL-1β、IL-6和TNF-α水平,Western blotting法检测各组小鼠大脑皮层组织中P38MAPK、P65NF-κB、p-P38MAPK和p-P65NF-κB蛋白表达水平。结果:与对照组比较,热射病组小鼠体质量丢失明显增加(P<0.05),热射病1和6h组小鼠肛温明显降低(P<0.05)。HE染色,对照组小鼠大脑皮层脑组织形态表现正常;热射病1h组小鼠大量脑细胞核固缩、核染色深,血管被压缩变形、管壁外大量水肿;热射病6h组小鼠核固缩细胞数量减少,血管外水肿减轻;热射病24h组小鼠核固缩脑细胞和血管外水肿少见。与对照组比较,热射病1和6h组小鼠大脑皮层组织中IL-1β、IL-6、TNF-α水平和p-P38MAPK、p-P65NF-κB蛋白表达水平明显升高(P<0.05);热射病6h组小鼠大脑皮层组织中IL-1β、IL-6、TNF-α水平和p-P38MAPK、p-P65NF-κB蛋白表达水平明显低于热射病1h组(P<0.05)。结论:热射病小鼠大脑皮层组织中炎症细胞因子水平升高,P38MAPK/P65NF-κB信号通路激活,这种中枢神经系统炎症反应可能与其信号通路激活有关。

Objective:To investigate the changes of the levels of interleukin-1β(IL-1β),interleukin-6(IL-6),tumor necrosis factor-α(TNF-α)and the P38 mitogen-activated protein kinase(MAPK)/P65 nuclear transcription factor-κB(P65 NF-κB)signaling pathways in the cerebral cortex tissue of the mice with heat stroke,and to elucidate its mechniasm.Methods:A total of 60 mice were randomly divided into control group,heat stroke 1 hgroup,heat stroke 6 hgroup,and heat stroke 24 hgroup(1,6,and 24 hafter leaving warehouse in the heat stroke model mice),and there were 15 mice in each group.HE staining was used to detect the morphology of cerebral cortexy tissue of the mice in various groups;the levels of IL-1β,IL-6 and TNF-αin cerebral cortex tissue of the mice in various groups were measured by ELISA method;the expression levels of P38 MAPK,P65 NF-κB,p-P38 MAPK and p-P65 NF-κB proteins in cerebral cortex tissue of the mice in various groups were determined by Western blotting method.Results:Compared with control group,the body mass loss of mice in heat stroke groups was increased(P<0.05),and the anal temperatures of the mice in heat stroke 1 hgroup and heat stroke 6 hgroup were significantly decreased(P<0.05).The HE staining results showed that the cerebral cortex tissue of the mice in control group were normal;in heat stroke 1 hgroup,a large number of brain cells were pyknosisd and stained darkly,the blood vessels were compressed and deformed,and a large number of edema was found outside the wall;in heat stroke 6 hgroup,the number of pyknosisd cells was decreased,and the extravascular edema was reduced;in heat stroke 24 hgroup,the pyknosisd brain cells and the extravascular edema were rare.Compared with control group,the levels of IL-1β,IL-6,TNF-αand the expression levels of p-P38 MAPK and p-P65 NF-κB proteins in cerebral cortex tissue of the mice in heat stroke 1 hgroup and 6 hgroup were increased(P<0.05).The levels of IL-1β,IL-6,TNF-αand the expression levels of p-P38 MAPK and p-P65 NF-κB proteins in cerebral cortex tissue of the mice in heat stroke 6 hgroup were lower than those in heat stroke 1 hgroup(P<0.05).Conclusion:The levels of inflammatory cytokines in cerebral cortex tissue of the mice with heat stroke are elevated,and the P38 MAPK/P65 NF-κB signaling pathway is activated.This inflammatory response of central nervous system may be related to the activation of signaling pathways.