There is a growing appreciation of the importance of circadian regulation in energy homeostasis, and the dysregulation of the circadian clock has been associated with obesity and metabolic abnormalities. A new study shows that adipocyte-specific deletion of a core circadian clock gene, Arntl (Bmal1), in mice shifts the timing of their feeding behavior, resulting in obesity.
Although it is a widely held thought that direct hormone action on peripheral tissues is sufficient to mediate the control of nutrient handling, the role of the central nervous system in certain aspects of metabolism has long been recognized. Furthermore, recent findings have suggested a more general role for the central nervous system in metabolic control, and have revealed the importance of a number of cues and hypothalamic circuits. The brain's contributions to metabolic control are more readily revealed and play a crucial part in catabolic states or in hormone deficiencies that mimic starvation.