基于代谢组学探究热习服血清生物标志物

Research on serum biomarkers of heat acclimation based on metabolomics

目的探讨热习服(HA)提升机体耐热能力的代谢产物变化特征,筛选热习服特异性的生物标志物。方法将14只C57BL/6小鼠随机分为对照(Con)组和热习服(HA)组,HA组小鼠每日在温度(35±1)℃,相对湿度(60±5)%的环境模拟舱中建立热习服模型,连续4周。结束后次日小鼠麻醉后收集眼眶血,并分离血清。采用液相色谱质谱联用技术,检测热习服小鼠血清代谢产物变化特征。结果通过主成分分析(PCA)和正交偏最小二乘判别分析(OPLS-DA)表明Con组和HA组样本有明显组间差异。与Con组相比,HA组小鼠血清代谢物中共筛选到51种具有显著差异的代谢物(变量权重值>1,P<0.05),其中24种上调,27种下调,这些差异代谢物主要集中在氨基酸代谢、碳水化合物代谢、辅因子和维生素代谢和消化系统等通路。利用京都基因与基因组百科全书(KEGG)富集分析,主要富集在蛋白质消化吸收(P<0.001)、缺氧诱导因子-1(HIF-1)信号通路(P=0.001)、癌症的中枢碳代谢(P=0.001)、维生素的消化吸收(P=0.002)、胰高血糖素信号通路(P=0.005)、D-谷氨酰胺和D-谷氨酸代谢(P=0.013)和氧化磷酸化(P=0.019)这7个代谢途径,并根据这些代谢途径筛选出一组与热习服密切相关的生物标志物。结论热习服小鼠血清代谢物发生显著改变,这些代谢物可作为判断机体耐热能力的生物标志物。

Objective To explore the characteristics of metabolic product changes in heat acclimation(HA)enhancing the body's heat tolerance,and screen specific biomarkers for heat acclimation.Methods Fourteen C57BL/6 mice were randomly divided into a control(Con)group and a heat acclimation(HA)group.The HA group mice were established daily in an environmental simulation chamber with a temperature of(35±1)℃and a relative humidity of(60±5)%for 4 consecutive weeks.The next day after the end,the mice were anesthetized and orbital blood was collected,and serum was separated.Liquid chromatograph mass spectrometer technology was used to detect changes in the main metabolites in the serum of HA group mice.Results Principal component analysis(PCA)and orthogonal partial least squares discriminant analysis(OPLS⁃DA)showed significant differences between the Con group and the HA group samples.Compared with the Con group,a total of 51 metabolites with significant differences were identified in the serum of HA group mice,of which 24 were upregulated and 27 were downregulated(variable importance in projection>1,P<0.05).These differential metabolites were mainly concentrated in pathways such as amino acid metabolism,carbohydrate metabolism,cofactor and vitamin metabolism,and digestive system.The Kyoto encyclopedia of genes and genomes(KEGG)pathway enrichment analysis showed these genes were mainly involved in protein digestion and absorption(P<0.001),hypoxia inducible factor⁃1(HIF⁃1)signaling pathway(P=0.001),central carbon metabolism of cancer(P=0.001),digestion and absorption of vitamins(P=0.002),glucagon signaling pathway(P=0.005),D⁃glutamine and D⁃glutamic acid metabolism(P=0.013)and oxidative phosphorylation(P=0.019).Based on these metabolic pathways,a set of biomarkers closely related to heat acclimation were determined.Conclusion There were significant changes in serum metabolites in heat acclimatized mice,and these metabolites might serve as biomarkers for assessing the body's heat tolerance.