持续高血压状态自发性高血压大鼠血清代谢组学研究

A serum metabolomics-based study on persistent hypertensive SHR

目的探讨持续高血压状态自发性高血压大鼠(spontaneously hypertensive rats,SHR)血清代谢物改变及可能相关的机制。方法随机各取6只雄性SHR和魏-凯二氏大鼠(Wistar-Kyoto rats,WKY)大鼠分别设为模型和对照组,标准饲养120 d,每周使用BP2000检测收缩压(systolic blood pressure,SBP)。取材后对其心肌组织行HE和Masson染色;采用超高效液相色谱质谱联用(ultra-high performance liquid mass spectrometry and tandem mass spectrometry,UPLC-MS)法检测血清差异性代谢物,并进一步对其进行GO与KEGG富集分析。结果模型组SBP呈逐步升高,约于20周龄达高峰后又趋于稳定,且在各时间点均明显高于对照组(P<0.001);伊红-苏木素(hematoxylin-eosin,HE)染色心肌组织排列紊乱,血管壁增厚,管腔缩小,肌间和管腔周围均出现均质粉染物质;Masson染色心肌组织可见大量胶原纤维沉积。血清代谢模式和个体差异代谢物两组间呈现明显分离趋势,共鉴定出44个潜在标志性代谢物,主要涉及神经活性受体配体相互作用、5-羟色胺(5-hydroxytryptamine,5-HT)突触传导通路、花生四烯酸(arachidonic acid,AA)代谢等代谢途径。结论持续高血压状态SHR存在明显的心肌和血管周围纤维化,其代谢模式明显偏离正常大鼠,血清标志性差异代谢物主要与调节交感神经活性与血管舒缩及抑炎有关。

Objective To investigate metabolomic changes in the serum of rats with persistent hypertensive SHR and reveal the possible pathogenesis.Methods Six male SHR and six WKY rats were selected at random and defined as the model group and the control group.Rats were given 120 d standard feeding and rat SBP was measured using the BP2000 platform once a week.Rat myocardial tissue was stained with HE and Masson staining and rat serum was detected by UPLCMS to identify significant metabolites.In addition,a GO and KEGG pathway enrichment analysis was performed.Results The SBP of the model group gradually increased and peaked at aged 20 weeks,which was followed by a plateau period.The SBP of SHR at all time points was much higher than that of the control group(P<0.001).HE staining showed that the myocardial tissue of the model group was in a disordered arrangement,and the vessel walls were thicker,while their lumen was narrower.Homogeneous,pink-colored substances were largely found in both the myocardium and around the lumen.Masson staining revealed a very large amount of collagen fiber accumulated in the myocardium of the model group.The serum metabolic patterns and individual differential metabolites of the two groups were evidently separated from each other,and a total of 44 potential landmark metabolites were finally identified,mainly involving neuroactive ligand-receptor interactions,5-hydroxytryptamine receptors,and arachidonic acid metabolism pathways.Conclusions Myocardial and perivascular fibrosis were identified in SHRs under long-term hypertension.Serum metabolomics of SHR obviously deviated from the normal metabolic pattern,and significant metabolites were primarily involved in regulating vasoconstriction and vasodilation,modulating the activity of the sympathetic nerve,and inhibiting the inflammatory response.