Cooperation of Liver Cells in the Regulation of Glucose Metabolism

Abstract

The liver plays a central role in the regulation of glucose homeostasis in mammals through the ability of hepatocytes to store glycogen during the resorptive phase (glucogenesis), and to release glucose in the postprandial period as a result of glycogenolysis and de novo glucose synthesis from noncarbohydrate substrates, such as lactate, glycerol, or amino acids, i.e., gluconeogenesis. Hepatic glucose production, necessary for survival in the fasting state, plays a key role in the maintenance of glycemia. The glucoregulatory function of hepatocytes is controlled mainly by insulin, glucagon, catecholamines, and glucocorticoids, whereas many other hormones, cytokines, and various mediators play an accessory role in the fine-tuning of glucose homeostasis to the requirements of specific physiological and pathophysiological situations (Cherrington 1999). In acute systemic inflammation many mediators released both extra- and intrahepatically are of great importance for the adaptation of the liver to the energetic needs of the whole body.