Regulation of adiponectin release and demonstration of adiponectin mRNA as well as release by the non-fat cells of human omental adipose tissue

• Published in: International Journal of Obesity 2008-03, Vol.32 (3), p.429-435
• Main Authors: Fain, J.N, Buehrer, B, Tichansky, D.S, Madan, A.K
• Format: Article
• Language: English
• Subjects: Adipocytes; Adipocytes - metabolism; adiponectin; Adiponectin - genetics; Adiponectin - metabolism; Adipose tissue; Adipose Tissue - metabolism; Adipose tissues; Adult; Age; Biological and medical sciences; Body fat; Cytokines; Diabetes; endogenous sources; Epidemiology; Etanercept; explants; Female; Genetic aspects; Glucose; Health Promotion and Disease Prevention; hormone secretion; human cell lines; Humans; Immunoglobulin G - pharmacology; in vitro studies; Insulin; Insulin - pharmacology; Insulin resistance; interleukin-8; Interleukin-8 - metabolism; Internal Medicine; Laparoscopy; Leptin - metabolism; Medical sciences; Medicine; Medicine & Public Health; Messenger RNA; Metabolic Diseases; Middle Aged; non-fat cells; Obesity; Obesity, Morbid - metabolism; omentum; Omentum - metabolism; original-article; preadipocytes; Properties; Protein hormones; Proteins; Public Health; Receptors, Tumor Necrosis Factor; RNA, Messenger - analysis; Science; Surgery; tumor necrosis factor-alpha; Tumor Necrosis Factor-alpha - antagonists & inhibitors; Tumor Necrosis Factor-alpha - metabolism; Tumor necrosis factor-TNF; women
• ISSN: 0307-0565; 1476-5497
• DOI: 10.1038/sj.ijo.0803745

Objective: Adiponectin is an adipokine produced by adipose tissue. The present studies examined the in vitro release of adiponectin by human omental adipose tissue explants as well as the mRNA content of freshly isolated non-fat cells and adipocytes plus cultured preadipocytes and adipocytes derived from omental fat. Results: The release of adiponectin was reduced while that of interleukin-8 (IL-8) was enhanced in tissue explants from morbidly obese women. The release of adiponectin was also reduced by one-third in explants from morbidly obese diabetic women while that of IL-8 was unaffected by diabetes. The release of adiponectin was enhanced by insulin and by inhibition of endogenous tumor necrosis factor (TNFα) using etancercept. Adiponectin was released in appreciable amounts by the undigested matrix obtained by collagenase digestion of adipose tissue. The release of adiponectin by non-fat cells (matrix+SV cells) was comparable to that by the adipocytes derived from the same amount of tissue while the adiponectin mRNA content of the pooled matrix and SV cell fractions was 40% of that in intact tissue. The adiponectin mRNA content was 48-fold greater in isolated adipocytes than in non-fat cells derived from adipose tissue. In contrast, the amount of adiponectin mRNA in vitro differentiated omental adipocytes was 1 × l0 6 -fold greater than that in cultured preadipocytes while that of leptin was 3 × 10 4 -fold greater. Conclusion: Adiponectin mRNA is present in the non-fat cells of freshly isolated adipose tissue and release by the non-fat cells derived from a gram of adipose tissue is comparable to that by adipocytes isolated from the same amount of tissue. While leptin is only released by mature adipocytes, adiponectin is released by both the non-fat cells and the fat cells derived from human omental adipose tissue.