背景:肠道L型肠内分泌细胞(EEC)是肠道化学感应细胞,通过营养消化和微生物发酵的腔内成分,响应G蛋白偶联受体(GPCR)的激活,分泌饱腹感激素GLP-1和PYY。G蛋白信号调节因子(RGS)蛋白是GPCR信号传导的负调节因子。RGS在EEC中的表达谱,它们在饱腹感激素分泌和肥胖中的潜在作用尚不清楚。
方法:使用单细胞RNA测序(scRNA-Seq)在瘦和肥胖的天然结肠EEC中完成RGS的转录组学分析,和人类空肠EEC,数据来自公开的RNAseq数据集(GSE114853)。使用内窥镜检查期间获得的整个粘膜肠组织完成了RGS验证研究61例患者(n=42OB,n=19瘦);对患者的一部分餐后血浆进行了GLP-1和PYY测定。将离体人肠培养物和体外过表达RGS9的NCI-H716细胞与非选择性RGS抑制剂一起暴露于GLP-1促分泌素并测定GLP-1分泌。
结果:结肠和空肠肠内分泌细胞的转录组学分析揭示了EEC中独特的RGS表达谱,并且进一步在GLP-1+L型EEC内。在肥胖症中,结肠EEC中的RGS表达谱改变。人肠道RGS9表达与BMI呈正相关,与餐后GLP-1和PYY呈负相关。人肠道培养物中的RGS抑制增加了GLP-1从EEC离体释放。过表达RGS9的NCI-H716细胞显示营养刺激的GLP-1分泌缺陷。
结论:本研究介绍了RGS在人EEC中的表达谱,肥胖的改变,并提示RGS蛋白作为从肠EEC分泌的GLP-1和PYY调节剂的作用。
背景:AA由NIH(C-SigP30DK84567,K23DK114460)支持,来自梅奥诊所生物医学发现中心的试点奖,以及与明尼苏达大学临床和转化科学研究所合作的梅奥临床中心临床和转化科学办公室的转化产品开发基金。
BACKGROUND: Gut L-type enteroendocrine cells (EECs) are intestinal chemosensory cells that secrete satiety hormones GLP-1 and PYY in response to activation of G-protein coupled receptors (GPCRs) by luminal components of nutrient digestion and microbial fermentation. Regulator of G-protein Signaling (RGS) proteins are negative regulators of GPCR signaling. The expression profile of RGS in EECs, and their potential role in satiety hormone secretion and obesity is unknown.
METHODS: Transcriptomic profiling of RGS was completed in native colonic EECs was completed using single-cell RNA sequencing (scRNA-Seq) in lean and obesity, and human jejunal EECs with data obtained from a publicly available RNAseq dataset (GSE114853). RGS validation studies were completed using whole mucosal intestinal tissue obtained during endoscopy in 61 patients (n = 42 OB, n = 19 Lean); a subset of patients\' postprandial plasma was assayed for GLP-1 and PYY. Ex vivo human intestinal cultures and in vitro NCI-H716 cells overexpressing RGS9 were exposed to GLP-1 secretagogues in conjunction with a nonselective RGS-inhibitor and assayed for GLP-1 secretion.
RESULTS: Transcriptomic profiling of colonic and jejunal enteroendocrine cells revealed a unique RGS expression profile in EECs, and further within GLP-1+ L-type EECs. In obesity the RGS expression profile was altered in colonic EECs. Human gut RGS9 expression correlated positively with BMI and negatively with postprandial GLP-1 and PYY. RGS inhibition in human intestinal cultures increased GLP-1 release from EECs ex vivo. NCI-H716 cells overexpressing RGS9 displayed defective nutrient-stimulated GLP-1 secretion.
CONCLUSIONS: This study introduces the expression profile of RGS in human EECs, alterations in obesity, and suggests a role for RGS proteins as modulators of GLP-1 and PYY secretion from intestinal EECs.
BACKGROUND: AA is supported by the NIH(C-Sig P30DK84567, K23 DK114460), a Pilot Award from the Mayo Clinic Center for Biomedical Discovery, and a Translational Product Development Fund from The Mayo Clinic Center for Clinical and Translational Science Office of Translational Practice in partnership with the University of Minnesota Clinical and Translational Science Institute.