Orexin A Controls Glucose Metabolism

Abstract

The orexin-A and orexin-B are a hypothalamic neuropeptides, involved in the regulation of feeding behaviour, sleep-wakefulness rhythm, and neuroendocrine homeostasis that influence the sympathetic nervous system activity, blood pressure regulation, and metabolic status, glycemic, and may contribute to increase diabetics morbidity and mortality. This review concentrates on the catabolic role of orexin, which paradoxically coexists with its anabolic feeding-inducing role. This review aims to provide insight into the biological mechanism that controls orexin’s role in energy expenditure and to discuss its significance in the context of glycemic control. On the other hands, hypothalamus regulates muscle glucose metabolism and its insulin sensitivity; in fact the ventromedial hypothalamus increases glucose uptake in certain peripheral tissues, including brown adipose tissue. The circumstance that it has been found a relationship between brown adipose tissue, orexins, glucose, insulin levels suggests new research focused on the possible roles of orexins in many anomalies of energy expenditure and of glucose homeostasis, with reference to the diabetic patient.