Hypothalamic astrocytes fine-tune the signals governing metabolism.

Astrocytes are known to have key roles in the neuroendocrine control of metabolism. The spectrum of actions of this cell population continues to expand as their heterogeneity is deciphered and new study approaches are employed. Astrocytes were first implicated in metabolic control when they were shown to participate in hypothalamic inflammation induced by high-fat diets, which leads to complications such as continued weight gain and glucose intolerance. In addition to their participation in pathophysiological processes associated with poor nutrition and obesity, these glial cells are now accepted as fundamental players in the physiological control of energy homeostasis. Along with their effect on neurons controlling appetite and energy expenditure, glial cells are implicitly involved in the generation of circadian rhythms, including eating and sleep patterns that affect metabolism and may link metabolism with other neuroendocrine systems such as puberty. The evolving concepts regarding astrocytes in metabolic control, including their participation in responses to currently used obesity drugs, highlight them as potential therapeutic targets. Here, we review advances in our understanding of how astrocytes participate in these processes, describe the mechanisms involved and discuss future directions.