应激大鼠模型结肠组织中spexin 的表达变化及代谢物质研究

Spexin expression and metabolites in the colon of the stress-induced rat model

分别通过避水应激(WAS)和母婴分离(NMS)的方法建立应激大鼠模型,观察大鼠粪便颗粒数以评价肠道运动的变化情况,通过实时荧光定量PCR检测大鼠结肠中spexin以及其受体GALR2的表达变化.同时通过UPLC/MS对结肠组织进行代谢组学检测,PLS-DA结合FDR统计分析筛选代谢差异物,与标准品的MS/MS碎片轮廓进行比对鉴定代谢物,通过MSEA分析代谢物相关通路的变化.结果发现WAS和NMS应激反应均可引起大鼠排便颗粒数显著增加,表明其肠道运动有所加强.定量PCR结果显示,应激反应可引起大鼠近端结肠和远端结肠部位spexin基因表达增高,同时增加近端结肠部位GALR2受体的表达,而远端结肠中GALR2表达变化不显著.通过对大鼠结肠组织中代谢组学分析发现,孕酮(progesterone)、亚油酸(Linoleic acid)、胆碱(Choline)、次黄嘌呤(Hypoxanthine)等脂类代谢产物在应激状态下均表现出显著变化.可见应激状态下大鼠结肠部位spexin、GALR2以及相关代谢产物均发生显著变化.结合前期研究结果推测,spexin及GALR2或代谢物的变化或与应激后肠道运动的变化密切相关.实验结果为进一步研究应激相关疾病的发病机理提供科学依据.后期进一步研究spexin与代谢产物之间的关联性可深入阐明其相关机制.

Recent studies have found that a novel neuropeptide spexin is significantly associated with stress responses in mice.At the same time,spexin plays an important physiological function in regulating the intestinal movement.Therefore,we speculate that the changes in intestinal motility under stress may be closely related to the expression of spexin.The stress-induced rat model was established by the method of water avoidance stress(WAS)and neonatal maternal separation(NMS),and the number of fecal pellets was observed to evaluate the changes of intestinal motility.The real-time fluorescence quantitative PCR was used to detect the expression changes of spexin and its receptor GALR2.Meanwhile,UPLC-MS/MS was used to detect metabolomics in the rat colon tissues.PLS-DA combined with FDR statistical analysis was used to screen metabolic differences,and related metabolites changes in the pathways were analyzed by MSEA.The results revealed that both WAS and NMS stress responses caused a significant increase in the number of defecation particles in rats,indicating that their intestinal motility was enhanced.Quantitative PCR results showed that stress response could increase the expression of spexin gene in the proximal and distal colon of rats and elevate the expression level of GALR2 receptor in the proximal colon,while the expression of GALR2 in the distal colon did not change significantly.A metabolomic analysis of rat colon tissues revealed that lipid metabolites such as progesterone,linoleic acid,choline,and hypoxanthine showed significant changes under a stress condition.The results showed that spexin,GALR2 and related lipid metabolites in the colon of rats changed significantly under stress.Combined with the previous research,the changes of these genes or metabolites may be closely related to the changes of intestinal motility after stress.The experimental results could provide a scientific basis for further research on the pathogenesis of stress-related diseases.Future study of the correlation between spexin and lipid metabolites could further elucidate the related mechanism.