Study of adipokine secretion and their functions
Date of Issue2012
School of Chemical and Biomedical Engineering
Due to the recent discoveries of a growing number of cytokines secreted by adipocytes (fat cells) termed as Adipokines, the simple paradigm of adipocytes as merely the depot of excess energy (fat) has quickly evolved into a new notion of these cells as multi-functional endocrine cells involving in an extraordinarily broad range of physiological functions including energy metabolism. And Given the essential involvements of adipokines in complex metabolic network, these secretory hormones play a pivotal role in the pathophysiology of metabolic disorders, such as, obesity and diabetes mellitus. Nevertheless, the regulatory mechanism of adipokine secretion and their functions remain obscure. We hypothesized that secretion of adipokines is highly regulated at autocrine, paracrine, and endocrine levels through cross-talks among themselves and with other metabolic factors, such as insulin, catecholamines and angiotensin II. In this work, three types of adipokines: leptin, resistin and apelin, were mainly focused because of their critical involvement in metabolic homeostasis. Regulation of leptin, resistin, and apelin secretion was studied. The autocrine, paracrine, and endocrine functions of these adipokines, for example, regulation of leptin and resistin on catecholamine secretion from adrenal chromaffin PC12 cells, and regulation of apelin on 3T3-L1 adipocyte differentiation and lipolysis, were also investigated. These studies would advance our current understanding on the regulations of adipokine secretion and the adipokine functions. Such understanding may lead to discovery of potential therapeutic targets for metabolic diseases.