[BIO Colloquium] The role of hypothalamic non-neuronal cells in the regulation of energy homeostasis
  • Jae Geun Kim, Ph.D. (Incheon National University)
  • SLS Colloquia / Nov 4th 04:00pm / AMRB 113

Astrocytes are the most abundant cells in the CNS, yet they have often been relegated to a less than prominent role in the control of complex brain functions supported by neuronal circuits. The regulation of food intake and energy expenditure is tightly linked to the synaptic plasticity of hypothalamic neural circuits, processes in which glial cells have also been implicated. However it has not yet been explored whether this involvement of glia is secondary or has an active role in the pro­motion of these processes initiated by leptin. We found that leptin receptors were expressed in hypothalamic astrocytes and that their conditional deletion led to altered glial morphology and synaptic inputs onto hypothalamic neurons involved in feeding control. Microglia, the smallest glial cell, is similar in nature to macrophage in the peripheral immune system and serves as a representative of the CNS immune system. Here we further investigated the potential role of microglia in the hypothalamic control of energy metabolism. Strikingly, we observed that activation of hypothalamic microglia resulted in a decrease of food intake and an increase of energy expenditure through the melanocortin pathway. These findings suggest an active role of glial cells in hypothalamic synaptic remodeling and control of energy metabolism.