Central Nervous System Control of Glucose Homeostasis

Abstract

Hypothalamus and brain stem play important roles in Glucose Homeostasis. There are two types of cells in the hypothalamus: Glucose excited (GE) and Glucose inhibited (GI). GE increases glucose concentration and GI decreases glucose concentration. They are located in ventromedial (VMH), arcuate, lateral, dorsomedial and paraventricular areas of hypothalamus. Nucleus of solitary tract, area postrema, dorsomedial nucleus of vagus and basolateral medulla are also related to glucose homeostasis. VMH contains sympathetic nucleus and upregulates plasma glucose and decreases hepatic glycogen, while lateral hypothalamus contains parasympathetic and down regulates plasma glucose. Through Glut-1, dependent transport glucose enters neurons and astrocytes. Glucose is metabolized and provides energy for GE and GI neurons. Their activity is guided by blood sugar level. Blood sugar level sends numerous signals through vagal pathway from periphery. Neuron astrocyte establishes via autonomic system connections with liver, pancreas, adrenal gland and maintains glucose homeostasis. Post prandial glucose levels are regulated by CNS.