ADIPSIN SECRETION RATE IN ADIPOSE-TISSUE FROM OMENTAL AND SUBCUTANEOUS DEPOTS OF LEAN AND MASSIVELY OBESE SUBJECTS

Adipsin is a serine protease with complement factor D activity which i s synthetized by adipocytes and its level has been found to be profoun dly decreased in mice with genetic and hypothalamic obesity. Recently human adipsin has been cloned and it has been shown that adipsin is he avily expressed in human adipose tissue; adipsin serum levels vary as a function of nutrition and adiposity and in one obese population no d eficiency in blood adipsin concentrations was observed. In the present study we investigated the regulation of adipsin release in different adipose depots in lean and obese subjects. The results demonstrate tha t subcutaneous adipose tissue secretes more adipsin than omental adipo se tissue, both in obese and lean subjects. Furthermore, fragments of subcutaneous and omental adipose tissue from obese subjects release mo re adipsin than fragments of analogous depots from lean subjects. Thus , in humans, adipsin seems to be differently regulated in different ad ipose depots.