SEMINAR
STROMALab UMR 5273 UPS/CNRS/EFS INSERM U1031, Toulouse, France
rown adipose tissue, which dissipates energy as heat via the uncoupling protein-‐1 (UCP1), is located in specific fat deposits or can emerge among white fat mass through the so-‐called browning process. Several hormones, enzymes, transcription factors and micro-‐RNAs have recently been shown to drive the emergence of inducible brown adipocytes in white adipose tissue. This study aimed to investigate whether the browning process is also controlled by the cellular metabolic environment. In particular, we evaluated the role of some metabolites and their respective receptors and transporters on recruitment and activation of brown-‐like adipose cells. Here, we show that lactate and ketone bodies are robust inducers of thermogenic gene expression including Ucp1 in both murine and human white differentiated adipocytes. We demonstrate that metabolites effect on Ucp1 is mediated by intracellular redox modifications, as a result of their transport through monocarboxylate transporters. Because this redox-‐dependent increase in Ucp1 expression promotes an oxidative phenotype with uncoupled mitochondria, browning appears as an adaptive mechanism to alleviate redox pressure. Our findings open new perspectives for the control of browning of adipose tissue and its physiological relevance.
Host: Prof. Luc Pellerin