Vagal pathways for systemic regulation of glucose metabolism

Maintaining blood glucose at an appropriate physiological level requires precise coordination of multiple organs and tissues. The vagus nerve bidirectionally connects the central nervous system with peripheral organs crucial to glucose mobilization, nutrient storage, and food absorption, thereby presenting a key pathway for the central control of blood glucose levels. However, the precise mechanisms by which vagal populations that target discrete tissues participate in glucoregulation are much less clear. Here we review recent advances unraveling the cellular identity, neuroanatomical organization, and functional contributions of both vagal efferents and vagal afferents in the control of systemic glucose metabolism. We focus on their involvement in relaying glucoregulatory cues from the brain to peripheral tissues, particularly the pancreatic islet, and by sensing and transmitting incoming signals from ingested food to the brain. These recent findings -largely driven by advances in viral approaches, RNA sequencing, and cell-type selective manipulations and tracings -have begun to clarify the precise vagal neuron populations involved in the central coordination of glucose levels, and raise interesting new possibilities for the treatment of glucose metabolism disorders such as diabetes.

Automated summary

Maintaining blood glucose at an appropriate physiological level requires coordination of multiple organs and tissues, with the vagus nerve playing a key role in central control. Recent studies have revealed the cellular identity, neuroanatomical organization, and functional contributions of vagal neurons in the regulation of systemic glucose metabolism. These findings provide new insights into the precise roles of vagal neurons in coordinating glucose levels and offer potential avenues for treating glucose metabolism disorders.