热应激对小鼠脾淋巴细胞活性及炎性基因表达的影响

Effects of heatstroke on splenic lymphocyte activity and expression of inflammatory genes in mice

目的热射病是病死率较高的致命性急症。系统性炎症反应综合征是中暑发生发展过程中的一个重要环节。作为机体最大的淋巴器官,文章研究将探索热应激对于脾脏功能的影响。方法体内实验中,将66只健康雄性BALB/c小鼠随机分为对照组以及热应激0 h、1 h、2 h、6 h、12 h、20 h、24 h、3 d、5 d、7 d组,每组6只。对照组小鼠不受热应激。热应激组小鼠于人工环境模拟舱进行加热,当直肠温度达到41.5℃时,核心温度维持在(41.5℃±0.2)℃,持续30 min。热应激后,各组小鼠分别在不同时间点观察体重、脾重量、脾系数的变化。体外实验中,9只12周龄健康雄性BALB/c小鼠于无菌条件下摘除脾,分离出小鼠原代脾淋巴细胞。原代淋巴细胞分别采用37℃(37℃组,作为对照)和42℃(42℃组,热应激)进行培养。实时定量聚合酶链反应(PCR)法检测IL-6、IL-10、MCP-1、IFN-γ、TNF-α、IL-12p70的表达变化。采用流式细胞仪检测细胞表面CD69的表达。结果与对照组比较,除12 h和5 d组之外,各热应激组小鼠Δ的脱水现象。体外实验显示,42℃组小鼠脾原代淋巴细胞中IFN-γ、IL-10、IL-6、MCP-1、TNF-α和IL-12p70基因的表达水平较37℃组显著增加(P<0.05),并且还能促进CD69的表达(P<0.01)。结论热应激对脾功能具有促进作用,能够增强脾淋巴细胞的炎症因子的基因以及CD69表达,为阐释热射病所致全身炎症反应的可能机制提供了基础参考。

ObjectiveHeat stroke is a fatal disease with high mortality.Systemic inflammatory response syndrome is a key process in the development of heatstroke.As the largest lymph organ of the body,this study will explore the effect of heatstroke on the function of the spleen.MethodsIn vivo,randomized 66 healthy male BALB/c mice into control groups and heat stress 0 h,1 h,2 h,6 h,12 h,20 h,24 h,3 d,5 d,7 d group,six in each group.The mice in the control group were not subjected to heat stress,random grouping of male BALB/c mice were exposed to heat in an environment-controlled chamber.When the rectal temperature reaches41.5℃,the core temperature was maintained at(41.5±0.2)℃for 30 minutes.After heat stress,the changes of body weight,spleen weight and spleen coefficient were observed at different time weight and spleen coefficient were observed at different time points.In vitro,spleen were removed from the mice under sterile conditions and the primary splenic lymphocytes were isolated from mice.Primary lymphocytes were cultured at 37℃(37℃group,control)and 42℃(42℃group,heat stress)respectively.Real time quantitative polymerase chain reaction(PCR)was used to detect the expression changes of IL-6,IL-10,MCP-1,IFN-γ,TNF-αand IL-12 p70.The expression of CD69 on the cell surface was detected by flow cytometry.ResultsIn contrast with the control group,the weight of heat stress mice was significantly reduced except for the 12 h and 5 d groups(P<0.05).Heat stress can lead to noticeable dehydration in mice.In vitro,heat stress could significantly increase the expression of IFN-γ,IL-10,IL-6,MCP-1,TNF-α,and IL-12 p70 genes in the spleen primary lymphocytes of mice(P<0.05),and also promote the expression of CD69(P<0.01).ConclusionHeat stress can promote the spleen function and enhance the gene of inflammatory factors and the expression of CD69 in spleen lymphocytes.Our study provides a laboratory reference for the explanation of the possible mechanism of systemic inflammation induced by heatstroke.