Description
Brown adipose tissue (BAT) is a thermogenic organ that dissipates stored energy as heat to maintain body temperature in infants and small mammals.  This process may also provide protection from development of diet-induced obesity.  We found that the bioactive lipid mediator lysophosphatidic acid (LPA) markedly decreases differentiation of cultured primary brown adipocyte precursors, while potent selective inhibitors of the LPA-generating enzyme autotaxin (ATX) promote differentiation.  Transgenic mice overexpressing ATX exhibited reduced expression of BAT-related genes in peripheral white adipose tissue and accumulated significantly more fat than wild-type controls when fed a high fat diet.  Our results indicate that ATX and its product LPA are physiologically relevant negative regulators of brown fat adipogenesis and suggest that a decrease in peripheral brown adipose tissue results in increased susceptibility to diet-induced obesity in mice.