Adipose tissue which used to be simply known as a storage of surplus energy is now perceived as an
independent and active endocrine organ, and various kinds of adipokine such as leptin (a protein secreted by fat cells), tumor necrosis factor-α (TNF-α), resistin, and adiponectin make major effects on obesity related metabolic diseases by controlling fat metabolism, energy homeostasis and insulin sensitivity. As the hormone called leptin was discovered at fat cells in 1994, it was started to study fat tissues as endocrine organs. Fat cells are engaged in complicated cell function coordination through signaling network of autonomic secretion system by secreting various kinds of adipokine, and are known to make effects on various organizations such as hypophyseal, pancreas, liver, muscle, vascular endothelium, and immune system. In obese patients, the secretion and coordination of such adipokines are biased abnormally and the secretion of specific adipokine becomes increased or decreased. Accordingly, to discover new adipokines and define their functions may enable us to find a new treatment strategy for metabolic disorders related to obesity.

Keywords: Adipokines, Obesity, Leptin, Adiponectin

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