Project description:Caloric restriction (CR) and methionine restriction driven enhanced lifespan and healthspan induces ‘browning’ of white adipose tissue (WAT), a metabolic response that increases heat production to defend core-body temperature. However, how specific dietary amino acids control adipose thermogenesis is unknown. Here, we identified that weight-loss induced by CR in humans reduces thiol-containing sulfur amino acid cysteine in WAT. Systemic cysteine-depletion in mice causes lethal weight-loss with increased fat utilization and browning of adipocytes that is rescued upon restoration of cysteine in diet. Mechanistically, cysteine restriction induced adipose browning and weight-loss requires sympathetic nervous system derived noradrenaline signaling via β3-adrenergic-receptors that is independent of FGF21 and UCP1. In obese mice, cysteine deprivation induced rapid adipose browning, increased energy expenditure leading to 30% weight-loss and reversed metabolic inflammation. These findings establish that cysteine is essential for organismal metabolism as removal of cysteine in the host triggers adipose browning and rapid weight loss.
Project description:Caloric restriction (CR) and methionine restriction driven enhanced lifespan and healthspan induces ‘browning’ of white adipose tissue (WAT), a metabolic response that increases heat production to defend core-body temperature. However, how specific dietary amino acids control adipose thermogenesis is unknown. Here, we identified that weight-loss induced by CR in humans reduces thiol-containing sulfur amino acid cysteine in WAT. Systemic cysteine-depletion in mice causes lethal weight-loss with increased fat utilization and browning of adipocytes that is rescued upon restoration of cysteine in diet. Mechanistically, cysteine restriction induced adipose browning and weight-loss requires sympathetic nervous system derived noradrenaline signaling via β3-adrenergic-receptors that is independent of FGF21 and UCP1. In obese mice, cysteine deprivation induced rapid adipose browning, increased energy expenditure leading to 30% weight-loss and reversed metabolic inflammation. These findings establish that cysteine is essential for organismal metabolism as removal of cysteine in the host triggers adipose browning and rapid weight loss.
Project description:Activation and recruitment of thermogenic cells in human white adipose tissues (“browning”) can counteract obesity and associated metabolic disorders. However, quantifying the effects of therapeutic interventions on browning remains enigmatic. Here, we devise a computational approach, profiling of fat tissue types (ProFAT), for the quantification of thermogenic potential of heterogeneous fat biopsies based on the prediction of white and brown adipocytes content from raw gene expression profiles. ProFat systematically integrates 103 mouse fat-derived transcriptomes to identify unbiased and robust gene signatures of brown and white adipocytes. Application of ProFAT to 80 mouse and 97 human transcriptional profiles from 14 independent studies correctly predicts browning capacity upon various physiological and pharmacological stimuli. Our study represents the most exhaustive comparative analysis of public data on adipose biology towards quantification of browning after personalized medical intervention. ProFat is freely available and should become increasingly powerful with the growing wealth of transcriptomics data.
Project description:As obesity has becoming an urged issue nowadays, delineation of the mechanisms of WAT tissue white-browning and beige adipose origin are of important topic. By the use of snRNA-seq, we can outline LepR cells play important role in the white-browning process and investigate the mechanisms participate at different white-browning treatments.
Project description:Brown and beige adipose tissue are emerging as distinct endocrine organs. These tissues are functionally associated with skeletal muscle, adipose tissue metabolism and systemic energy expenditure, suggesting an interorgan signaling network. Using metabolomics, we identify 3-methyl-2-oxovaleric acid, 5-oxoproline, and β-hydroxyisobutyric acid as small molecule metabokines synthesized in browning adipocytes and secreted via monocarboxylate transporters. 3-methyl-2-oxovaleric acid, 5-oxoproline and β-hydroxyisobutyric acid induce a brown adipocyte-specific phenotype in white adipocytes and mitochondrial oxidative energy metabolism in skeletal myocytes both in vitro and in vivo. 3-methyl-2-oxovaleric acid and 5-oxoproline signal through cAMP-PKA-p38 MAPK and β-hydroxyisobutyric acid via mTOR. In humans, plasma and adipose tissue 3-methyl-2-oxovaleric acid, 5-oxoproline and β-hydroxyisobutyric acid concentrations correlate with markers of adipose browning and inversely associate with body mass index. These metabolites reduce adiposity, increase energy expenditure and improve glucose and insulin homeostasis in mouse models of obesity and diabetes. Our findings identify beige adipose-brown adipose-muscle physiological metabokine crosstalk.
Project description:Visceral white adipose tissue is closed correlated with obesity and metabolic dysfunction. Epididymal adipose tissue (eWAT) is considered as typical visceral white adipose tissue. Induction of browning of white adipose tissue improves metabolic dysfunction such as insulin resistance. In contrast to mice subcutaneous adipose tissue, visceral fat do not show significant browning under 4°C. However,under physiologically tolerable low temperature visceral adipose tissue can turn brown. We used microarrays to detail the global programme of gene expression in C57Bl/6 mice epididymal adipose tissue exposed to thermoneutral 30°C, 4°C and temperatures lower than 4°C.
Project description:Cancer associated cachexia (CAC) causes white adipose tissue (WAT) lose by inhibiting adipogenesis, and promoting lipolysis, fat oxidation and browning. To uncover the specific lncRNAs and mRNAs involved in these processes, we used RNA microarray to identify the transcriptomes and found numerous lncRNAs and mRNAs differentially expressed in the fat tissue between CAC and normal mice.
Project description:Differentiation of brown adipocytes is a crucial process for adaptive thermogenesis, which is stimulated by various factors. We found robust browning of inguinal white adipose tissue in UCP1/ApoE-DKO mice, but not in ApoE-KO mice, under high-fat diet condition. We used microarray to determine the genes specifically regulated in the browning white adipose tissue in UCP1/ApoE-DKO mice.
Project description:Cancer-associated cachexia (CAC) is a wasting syndrome caused by malignant tumors. Fat loss plays a significant role in the pathophysiology of cancer-associated cachexia. The mechanism of fat loss in CAC includes enhancement of lipolysis, inhibition of lipogenesis and browning of white adipose tissue. In order to discover potentially functional genes in white adipose tissue of CAC, we used transcriptome sequencing technology to find research-valuable genes in white adipose tissue (WAT) of CAC rodent model. C57/bl6 mice with LLC tumors were used as the in vivo model for CAC, while normal mice subcutaneously injected with phosphate buffer solution were used as the control group. Overall, our data revealed genes that were differentially expressed in the white adipose tissue of LLC tumor-bearing mice, providing a molecular framework for the investigation into CAC fat loss.
Project description:Brown and beige fat share a remarkably similar transcriptional program that supports fuel oxidation and thermogenesis. The chromatin-remodeling machinery that governs genome accessibility and renders adipocytes poised for thermogenic activation remains elusive. BAF60a serves an indispensable role in cold-induced thermogenesis in brown fat. Surprisingly, fat-specific BAF60a inactivation triggers more pronounced browning of inguinal white adipose tissue. These results suggest a dichotomous role of BAF60a-mediated chromatin remodeling in transcriptional control of brown and beige gene programs. To elucidate the mechanism, we performed microarray annalysis in inguinal white adipose tissues from mice after chronic cold exposure.