基于16S rDNA扩增子测序及靶向代谢组学探究“脾应长夏”的物质基础

Study on the material basis of'spleen corresponds to late summer'based on 16S rDNA amplicon sequencing and target metabonomics

目的:通过长夏时节肠道菌群及其代谢短链脂肪酸的季节性特征研究松果腺介导的“脾应长夏”的物质基础,丰富中医“天人相应”理论内涵。方法:将SD大鼠随机分为空白组、伪手术组和手术组,采用人工气候模拟系统模拟长夏气候特征饲养4周,观察各组大鼠一般状态及粪便含水率,从宏观上对比研究脾运化水液能力;应用16S rDNA扩增子测序和靶向代谢组学技术进一步剖析松果腺对大鼠肠道菌群及短链脂肪酸的调控情况。,结果:切除大鼠松果腺后,第14、28天,手术组大鼠体质量与伪手术组比较,显著下降(P<0.05),粪便含水率比空白组显著增加(P<0.01);长夏环境中大鼠肠道菌群以厚壁菌门为主,伪手术组代表性物种为梭菌目、毛螺菌科和瘤胃菌科等,而手术组厚壁菌门丰度有所减少,代表性物种为脱硫弧菌属、韦荣球菌科以及苏黎世杆菌科;手术组大鼠肠道短链脂肪酸与空白组比较,乙酸、异丁酸、丁酸、戊酸、异戊酸和己酸显著降低(P<0.01,P<0.05)。结论:“脾应长夏”的物质基础可能与松果腺通过调节肠道菌群及短链脂肪酸代谢实现机体对自然环境的适应调节相关。

Objective: To investigate the material basis of pineal gland-mediated ’spleen corresponds to late summer’ through the seasonal characteristics of intestinal flora and its metabolism of short-chain fatty acids in late summer, and to enrich the connotation of ’correspondence between man and nature’ theory. Methods: SD rats were randomly divided into control group, sham-operated group, and operated group with pineal glands removed. They were reared in late summer environment using a climate simulation system, and the general status and fecal water content of the rats in each group were observed. The regulation of pineal gland on rats’ intestinal flora and short-chain fatty acids were further analyzed using 16 S rDNA amplicon sequencing and targeted metabolomics techniques. Results: After the pineal gland was removed, the body weight of the rats was significantly lower than that of the sham-operated group(P<0.05), and the fecal water content was significantly increased compared with the control group(P<0.01). In late summer environment, the intestinal flora was dominated by Phylum Firmicutes. The representative species in the sham-operated group were Clostridiales, Lachnospiraceae, Ruminococcaceae, while the abundance of Firmicutes in the operated group was reduced. Representative species in the operated group were Desulfovibrio, Erysipelotrichaceae, Turicibacter. And compared with the control group, acetic acid, isobutyric acid, butyric acid, valeric acid, and hexanoic acid were significantly reduced in the intestinal of operated group rats(P<0.01, P<0.05). Conclusion: The material basis of ’spleen corresponds to late summer’ may be related to the pineal gland’s adaptation to the natural environment by regulating intestinal flora and short-chain fatty acid metabolism.