Adiponectin is an adipocytokine produced mainly from liver and adipose tissue and expressed in various tissues with multifunctional effects. Little is known about adiponectin expression and regulation in cattle and that is the purpose of this study. Using northern blot analysis analysis, adiponectin expression was confirmed in mature differentiated bovine adipocytes and not in stromal vascular cells. When differentiated mature cells incubated with short chain fatty acids (SCFA), (Acetate, Butyrate and Propionate) in a dose of 1mM for 48 h, adiponectin expression was significantly increased. Unlike SCFA, medium and long chain fatty acids (MCFA & LCFA respectively) reduced adiponectin expression. Co-treatment of LCFA with acetate inhibited acetate induced adiponectin expression. The down-regulation of LCFA is PPAR dependent pathway. Moreover, insulin, dexamethasone, noradrenaline, tri-iodothyronin (T3), and tumor necrosis factor- (TNF- significantly down-regulated adiponectin expression while estrogen has no effect, while troglitazone upregulated adiponectin expression in bovine adipocytes. The results clearly show that adiponectin is adipokine secreted from bovine mature adipocytes to act in response to nutritional factors and host defensive response of cattle and is new target for treatment of insulin resistance. |
