Turning WAT into BAT: a review on regulators controlling the browning of white adipocytes

Kinyui Alice Lo,Lei Sun

doi:10.1042/bsr20130046

Abstract

Adipose tissue has a central role in the regulation of energy balance and homoeostasis. There are two main types of adipose tissue: WAT (white adipose tissue) and BAT (brown adipose tissue). WAT from certain depots, in response to appropriate stimuli, can undergo a process known as browning where it takes on characteristics of BAT, notably the induction of UCP1 (uncoupling protein 1) expression and the presence of multilocular lipid droplets and multiple mitochondria. How browning is regulated is an intense topic of investigation as it has the potential to tilt the energy balance from storage to expenditure, a strategy that holds promise to combat the growing epidemic of obesity and metabolic syndrome. This review focuses on the transcriptional regulators as well as various proteins and secreted mediators that have been shown to play a role in browning. Emphasis is on describing how many of these factors exert their effects by regulating the three main transcriptional regulators of classical BAT development, namely PRDM16 (PR domain containing 16), PPARγ (peroxisome proliferator-activated receptor γ) and PGC-1α (peroxisome proliferator-activated receptor γ coactivator 1α), which have been shown to be the key nodes in the regulation of inducible brown fat.

Highlights

There are two types of adipose tissue, namely WAT and brown adipose tissue (BAT)
Lineage tracing experiments in mice shows that BAT, similar to skeletal muscle, arises from myogenic factor 5 (Myf5)-expressing precursors [3]
Upon physiological stimuli such as chronic cold exposure, hormonal stimuli such as irisin, pharmacological treatment such as peroxisome-proliferator-activated receptor γ (PPARγ) agonist or β-adrenergic stimulation, a brown-fat-like gene expression program [e.g. uncoupling protein 1 (UCP1), cell death-inducing DFFA-like effector a (Cidea) and Dio2] is induced in a subset of Myf5 − adipocytes in WAT

Summary

Introduction

There are two types of adipose tissue, namely WAT (white adipose tissue) and BAT (brown adipose tissue). Needed for induction of browning in subcutanoues fat p107 knockout mice, primary adipocytes Repressing expression of PGC-1α Treatment with PPARγ activator rosiglitazone induces the expression of UCP1, a BAT hallmark gene responsible for thermogenesis, in WAT of both mouse and human [19,20].

Results

Conclusion