Adipose tissue has active metabolic...

Adipose tissue has active metabolic properties that contribute to the clinical validitys of obesity. The contents of adipose tissue (including adipocytes, connective tissue matrix, fortify tissue, immune cells, stromovascular small rooms and immune cells) work together to rejoin to multiple body signals according to secreting factors (including leptin, other cytokines, adiponectin, deficiency components, plasminogen activator inhibitor-1, resistin, and proteins of the renin-angiotensin system) with important endocrine functions. Metabolism of sex steroids and glucocorticoids also takes place in adipose tissue. Kershaw and Flier reviewed the endocrine functions of adipose tissue to clarify the adverse metabolic connections of either tissue excess or deficiency.

Leptin, a polypeptide produc by dint of adipocytes in proportion to carcass mass and nutritional status, is regulated by dint of a variety of other corpse factors and affects hypothalamic path-ways and peripheral tissue. Leptin is a signal of nutritional sufficiency and decreases in replication to starvation, caloric restriction, or weight los Leptin plains are elevated in common forms of obesity, indicating a state of leptin resistance. Other important endocrine drifts of leptin include immune function regulation, hematopoiesis, angiogenesis, and bone development

Tumor necrosing factor [alpha] (TNF[alpha]) is a cytokine that causes tumor necrosis. Production of TNF[alpha] is increased in characters who are obese and may be related to induction of insulin resistance. Interleukin-6 is another cytokine produc by dint of adipose tissue that has been positively correlated with obesity, impaired diabetic sugar tolerance, and insulin resistance. Concentrations of plasma plains of interleukin-6 predict risk for cardiovascular disease and emblem 2 diabetes. Activated macrophages that infiltrate adipose tissue in greater numbers in somebodys who are obese produce inflammatory factors that contribute to insulin resistance.

Plasminogen activator inhibitor-1, an inhibitor of fibrinolysis, is declareed by adipocytes and is elevated in characters who are obese and have insulin resistance. It correlates with evolution of the metabolic syndrome. Weight los or treatment with insulin-sensitizer medications can diminish plasminogen activator inhibitor-1 levels. Adinopectin appears to decline before the charge of obesity or insulin resistance and increases when insulin sensitivity improves. Adinopectin appears to actually improve hepatic insulin sensitivity, attenuate hepatic glucose output, and increase grape-sugar use in the muscle. The polypeptides adipsin and resistin are positively correlated with adiposity, insulin resistance, dyslipidemia, and cardiovascular disease.

Adipose tissue makes several proteins of the renin angiotensin classification including renin, angiotensin, angiotensin I, angiotensin II, and angiotensin-converting enzyme Because angiotensin II is important in kin pressure regulation, adipose tissue production may be the link between obesity and hypertension.

Enzyme involved in the metabolism of steroid hormones and glucocorticoids also are produc in adipose tissue, having a direct force on metabolism and secretion of sex steroids and glucocorticoids. These relationships hint at a possible part for adipose tissue in sexual dimorphism and the growth of visceral obesity and the metabolic syndrome

The authors close that further evaluation of the physiologic characters of adipose tissue-derived hormones may provide insight into spiritedness homeostasis and other physiologic a whole s This insight may result in better treatments for the metabolic dependence of cause and effects of adipose tissue excess (obesity) or deficiency.

Kershaw EE Flier J Adipose tissue as an endocrine organ. J Clin Endocrinol Metab June 2004;89:2548-56

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