Project description:Brown adipocytes represent a specialized type of mammalian adipocytes able to uncouple nutrients catabolism and ATP generation to dissipate energy as heat. They play an important role in mammals, allowing non-shivering thermogenesis to regulate body temperature in response to cold exposure. In humans, the brown fat tissue is dispersed in small depots found throughout the neck and trunk region. Increasing brown fat activity either with drug treatment or with cell therapy approaches are considered as potential approaches for the treatment of metabolic syndrome and obesity. The recent development of in vitro differentiation strategies relying on human pluripotent stem cells (hPSCs) offers in theory the possibility to produce unlimited amounts of BAT. A strategy efficiently applied to several tissues is to recapitulate step by step the development of the tissue of interest by exposing hPSCs to the signaling cues used during normal embryonic development. However, this strategy has proven difficult to implement for brown fat as the development of this tissue is poorly characterized. Here, we first used single cell RNA sequencing to characterize the development of interscapular brown fat in mouse. Our analysis identified a previously unrecognized population of brown adipocytes precursors characterized by expression of the transcription factor GATA6. We showed that this precursor population can be efficiently generated from hPSCs by modulating the signaling pathways identified our transcriptomic analysis in paraxial mesoderm precursors differentiated in vitro. These precursors can in turn be efficiently converted into functional brown adipocytes which can respond to adrenergic stimuli by increasing their metabolism resulting in heat production.
Project description:Brown adipocytes represent a specialized type of mammalian adipocytes able to uncouple nutrients catabolism and ATP generation to dissipate energy as heat. They play an important role in mammals, allowing non-shivering thermogenesis to regulate body temperature in response to cold exposure. In humans, the brown fat tissue is dispersed in small depots found throughout the neck and trunk region. Increasing brown fat activity either with drug treatment or with cell therapy approaches are considered as potential approaches for the treatment of metabolic syndrome and obesity. The recent development of in vitro differentiation strategies relying on human pluripotent stem cells (hPSCs) offers in theory the possibility to produce unlimited amounts of BAT. A strategy efficiently applied to several tissues is to recapitulate step by step the development of the tissue of interest by exposing hPSCs to the signaling cues used during normal embryonic development. However, this strategy has proven difficult to implement for brown fat as the development of this tissue is poorly characterized. Here, we first used single cell RNA sequencing to characterize the development of interscapular brown fat in mouse. Our analysis identified a previously unrecognized population of brown adipocytes precursors characterized by expression of the transcription factor GATA6. We showed that this precursor population can be efficiently generated from hPSCs by modulating the signaling pathways identified our transcriptomic analysis in paraxial mesoderm precursors differentiated in vitro. These precursors can in turn be efficiently converted into functional brown adipocytes which can respond to adrenergic stimuli by increasing their metabolism resulting in heat production.
Project description:We performed a genome-wide deep sequencing analysis of the microRNAs abundant in mesenchymal stem cells (MSCs) derived from murine brown adipose tissue and in in vitro differentiated mature brown adipocytes. Several microRNAs were identified as differentially regulated when comparing datasets from MSCs vs. mature fat cells. These microRNAs may have an implication in the regulation of adipogenesis as well as thermogenesis in brown adipose tissue (BAT). Examination of BAT-derived MSCs (BAT-MSC; 1 sample) and in vitro differentiated mature brown fat cells (BAT-DIFF; 1 sample) vertis biotechnologie AG, D-85354 Freising, Germany (library construction and sequencing)
Project description:We performed a genome-wide deep sequencing analysis of the microRNAs abundant in mesenchymal stem cells (MSCs) derived from murine brown adipose tissue and in in vitro differentiated mature brown adipocytes. Several microRNAs were identified as differentially regulated when comparing datasets from MSCs vs. mature fat cells. These microRNAs may have an implication in the regulation of adipogenesis as well as thermogenesis in brown adipose tissue (BAT).
Project description:We report the RNA expression of the mature brown fat from 6 week old wild type (WT) and PHOSPHO1 knockout (KO) mice. Mature brown fat was isolated from brown adipose tissue after collagenase digestion. Increased expression of mitochondrial genes is found in KO brown fat.
Project description:We performed ChIP-seq to chart genome-wide maps of H3K27me3 in brown preadipocytes and mature brown adipocytes. We observed a subset of brown fat-specific genes, but not common fat genes or white fat-specific genes, possess the H3K27me3 mark in preadipocytes, and this mark is erased in mature adipocytes.
Project description:We performed ChIP-seq to chart genome-wide maps of H3K27me3 in brown preadipocytes and mature brown adipocytes. We observed a subset of brown fat-specific genes, but not common fat genes or white fat-specific genes, possess the H3K27me3 mark in preadipocytes, and this mark is erased in mature adipocytes. H3K27me3 ChIP-seq in brown preadipocytes and mature adipocytes.
Project description:Used to control identified tissue type, the brown fat, white fat and skeletal muscle were dissected from mice (N=3) at room temperature (23C)
Project description:Human brown fat tumors (hibernomas) display concomitant loss of the tumor suppressor genes MEN1 and AIP. In the present study, we hypothesized that the brown fat phenotype is attributed to these mutations. Accordingly, we demonstrate that silencing of AIP in human brown preadipocytic and white fat cell lines results in the induction of the brown fat marker UCP1. In human adipocytic tumors, loss of MEN1 was found both in white (one out of 51 lipomas) and brown fat tumors. In contrast, concurrent loss of AIP was always accompanied by a brown fat morphology. We conclude that this white-to-brown phenotype switch in brown fat tumors is mediated by the loss of AIP.
Project description:We performed RNA-Seq for brwon fat, epididymal white fat and soleus muscle of mice to identify brown fat-selective, white fat-selective and common fat genes. RNA-Seq for brown fat, white fat and soleus muscle of wild type C56BL6 mice.