Adipokines secretion in feline primary adipose tissue culture in response to dietary fatty acids.

Abstract

BACKGROUND: Obesity in cats has been associated with alterations in adipokines including: adiponectin, interleukin-6 (IL6), and tumor necrosis factor-&#x3b1; (TNF&#x3b1;). Omega-3 polyunsaturated fatty acids have multiple beneficial effects on obesity-associated disorders, and therefore may alleviate these alterations. This study aimed to determine the effects of body condition, fat depot, troglitazone, and different fatty acids on secretion of adiponectin, IL6 and TNF&#x3b1; from adipose tissue of healthy cats. Subcutaneous and visceral adipose tissue samples were collected from 18 healthy intact female cats, and body condition score (Range 3-7/9) was determined. Concentrations of adiponectin were measured in mature adipocytes cultures and concentrations of IL6 and TNF&#x3b1; were measured in stromovascular cells cultures following treatment with control medium, troglitazone at 10&#x2009;&#x3bc;M, eicosapentaenoic acid, arachidonic acid, or palmitic acid, at 25, 50, or 100&#x2009;&#x3bc;M. RESULTS: Stromovascular cells of visceral origin secreted higher concentrations of IL6 than corresponding cells of subcutaneous origin (P&#x2009;=&#x2009;0.003). Arachidonic acid treatment at 25, 50, and 100&#x2009;&#x3bc;M increased IL6 secretion in subcutaneous (P&#x2009;=&#x2009;0.045, P&#x2009;=&#x2009;0.002, and P&#x2009;<&#x2009;0.001, respectively) and visceral (P&#x2009;=&#x2009;0.034, P&#x2009;=&#x2009;0.001, and P&#x2009;<&#x2009;0.001, respectively) stromovascular cells. Eicosapentaenoic acid treatment increased TNF&#x3b1; secretion in subcutaneous stromovascular cells at 25, 50, and 100&#x2009;&#x3bc;M (P&#x2009;=&#x2009;0.002, P&#x2009;=&#x2009;0.001, and P&#x2009;=&#x2009;0.015, respectively) and in visceral stromovascular cells at 50&#x2009;&#x3bc;M (P&#x2009;<&#x2009;0.001). No significant effect on medium adiponectin concentration was observed following troglitazone treatment (P&#x2009;=&#x2009;0.4) or fatty acids treatments at 25 (P&#x2009;=&#x2009;0.2), 50 (P&#x2009;=&#x2009;0.8), or 100 (P&#x2009;=&#x2009;0.7) &#x3bc;M. Body condition score did not have significant effects on medium concentrations of adiponectin (P&#x2009;=&#x2009;0.4), IL6 (P&#x2009;=&#x2009;0.1), or TNF&#x3b1; (P&#x2009;=&#x2009;0.8). CONCLUSIONS: This study demonstrated higher basal secretion of IL6 from visceral compared to subcutaneous adipose tissue, a stimulatory effect of arachidonic acid on secretion of IL6 and a stimulatory effect of eicosapentaenoic acid on TNF&#x3b1; from feline adipose tissue.