Fig. 6

A Schematic diagram of adiponectin-mediated thermogenic regulation in brown and “beige” adipocytes. Our data suggest that adiponectin may regulate thermogenesis in brown adipocytes via the following 4 independent and complementary cellular/molecular mechanisms: 1) Ablation of adiponectin decreases β3-AR expression, which directly inhibits UCP-1 gene expression and activity. 2) Ablation of adiponectin inhibits insulin signaling, which may reduce UCP-1 activity. 3) Ablation of adiponectin suppresses the signaling pathway of AMPK-SIRT1, which may in turn result in reduced mitochondrial biogenesis. 4) Ablation of adiponectin impairs mitochondrial dynamics in BAT, which may contribute to thermogenic dysfunction. Collectively, adiponectin ablation diminishes thermogenic activation by decreasing adrenergic activation, and impairing mitochondrial biosynthesis and/or dynamics, thus suppressing thermogenesis in brown and “beige” adipocytes