Transcriptomics analysis of human jejunal enteroendocrine cells after vertical sleeve gastrectomy
ABSTRACT: We report here the transcriptome of a population enriched in enteroendocrine cells from human jejunum from patients before or after gastrectomy. We analyze the effect of surgery on gene expression and found very little effect on EEC transcriptome Overall design: 2 conditions: pre operative and post operative
Project description:We report here the transcriptome of sorted enteroendocrine cells from duodenum, ileum and colon from mice after vertical sleeve gastrectomy or sham operation, weight matched or not. We analyze the effect of region of origin and surgery and gene expression and found that only region of origin had an impact on EEC transcriptome Overall design: 3 conditions (VSG, sham-adlibitum and sham-weightmatched) from 3 regions (duodenum, ileum and colon) with 6 replicates for each
Project description:Bariatric surgery, an effective treatment for obesity and diabetes, leads to profound remodeling of whole body energy homeostasis. We utilized a mouse model of vertical sleeve gastrectomy (VSG), a common bariatric surgery as a tool to identify novel secreted proteins and peptides that might act as important metabolic regulators. We analyzed gene expression in the stomach and intestines following VSG or sham surgery in diet-induced obese mice and sought to identify differentially regulated genes encoding secreted proteins/peptides. Overall design: Gene expression analysis of 5 different mouse intestinal tissues after VSG or sham surgery
Project description:Profiling of the murine peptidome along the gastrointestinal tract and pancreas in vertical sleeve gastrectomy and sham operated mice. The study compares the peptidome of various portions of the GI tract using intact mass spectrometry and database searching. These peptides included most gut hormones including proglucagon derived peptides, PYY, GIP, somatostatin, neurotensin amongst others.
Project description:We report the expression profiles of ileal samples extracted from obese male C57Bl6 mice following vertical sleeve gastrectomy or sham surgery, focusing of gene signatures indicative of altered bile acid metabolism. We induced obesity in male C57bl6 mice through a high-fat diet. At 8 weeks, they were submitted to either a vertical sleeve gastrectomy (VSG) or a sham surgery; following surgery VSG mice were fed ad libitum while sham controls were pair-fed (SPF) to the experimental animals. During the four perioperative days, mice were fed a liquid Osmolite diet. Approximately 8 weeks after surgery mice were fasted overnight and gavaged with .5mL Osmolite; after one hour mice were sacrificed and the terminal ileum were extracted. RNA was extracted, quantified, and compared between VSG and SPF experimental groups.
Project description:Vertical sleeve gastrectomy (VSG) produces sustainable weight loss, remission of type 2 diabetes (T2D), and improvement of nonalcoholic fatty liver disease (NAFLD). However, the molecular mechanisms underlying the metabolic benefits of VSG have remained elusive. We have previously demonstrated that diet-induced obesity leads to chromatin modifications in the liver of mice. We demonstrate here that VSG in C57BL/6J wild-type male mice can reverse these chromatin modifications and thereby impact the expression of key metabolic genes. Genes involved in lipid metabolism, especially omega-6 fatty acid metabolism, are up-regulated in livers of mice after VSG while genes in inflammatory pathways are down-regulated after VSG. Consistent with gene expression changes, regulatory regions near genes involved in inflammatory response displayed decreased chromatin accessibility after VSG. Our results indicate that VSG induces global regulatory changes that impact hepatic inflammatory and lipid metabolic pathways, providing new insight into the mechanisms underlying the beneficial metabolic effects induced by VSG. Overall design: Chromatin accessibility and transcriptome profiles of VSG, Sham and Control mice liver in duplicates.
Project description:Enteroendocrine cells (EECs) sense intestinal content and release hormones to regulate gastrointestinal activity and systemic metabolism and food intake. Little is known about the molecular make-up of human EEC subtypes and the regulated secretion of individual hormones. Here we describe an organoid-based platform for functional studies of human EECs. EEC formation is induced in vitro by transient expression of NEUROG3. A set of gut organoids was engineered in which the major hormones are fluorescently tagged. A single-cell mRNA atlas was generated for the different EEC subtypes, and their secreted products were recorded by mass-spectrometry. We note key differences with murine EECs, including in hormones, sensory receptors and transcription factors. Notably, several novel hormone-like molecules were identified. Inter-EEC communication is exemplified by Secretin-induced GLP-1 secretion. Indeed, individual EEC subtypes carry receptors for various EEC hormones. This study provides a rich resource to study human EEC development and function.
Project description:Profiling of the human jejunum peptidome before and after total gastrectomy. The study compares the peptidome of jejunum using intact mass spectrometry and database searching. These peptides included most gut hormones including proglucagon derived peptides, PYY, GIP, Motilin somatostatin and neurotensin amongst others.
Project description:Lgr5+ adult intestinal stem cells are highly proliferative throughout life. Single Lgr5+ stem cells can be cultured into 3D epithelial organoids containing all cell types at nearnormal ratios. Culture conditions to generate the main cell types have been established previously, but signals inducing the various types of enteroendocrine cells (EECs) have remained elusive. Here we generate quiescent Lgr5+ stem cells in vitro by inhibition of the EGF-receptor (EGFR) and mitogen-associated protein kinase (MAPK) signaling pathways in organoids, a state that can be readily reversed. Quiescent Lgr5+ stem cells gain a distinct molecular signature, biased towards EEC differentiation. Indeed, combined inhibition of Wnt, Notch and MAPK pathways efficiently generates a diversity of EEC subtypes in vitro. Our observations uncouple Wnt-dependent stem cell maintenance from EGF-dependent proliferation and cell fate choice, and provide an in vitro approach for the study of the elusive EECs. Overall design: We established a stable culture of quiescent Lgr5+ intestinal stem cells in culture. These highly resemble quiescent secretory precursors, which has high EEC differentiation potential. Following on this lead, we elucidated what signals are required to generate EEC cells of all varieties, and provide a method to produce these EEC cells in large numbers.