Adiponectin and energy homeostasis: consensus and controversy

Adiponectin regulates energy homeostasis through the modulation of glucose and fatty acid metabolism in peripheral tissues. However, its central effect on energy balance remains unclear and controversial. Despite the disparate data, recent advances in our understanding of the signal transduction mechanisms used by adiponectin in the periphery and in the hypothalamus suggest that intracellular cross-talk between adiponectin, leptin and insulin may occur at several levels. The present review will summarize recent reports describing the peripheral and central effects of adiponectin and discuss progress concerning its molecular mechanisms. We will also particularly focus on apparent controversies and related mechanisms associated with the central effects of adiponectin on energy homeostasis.