METABOLIC EFFECTS OF NICOTINE ON HUMAN ADIPOSE-TISSUE IN ORGAN-CULTURE

Fragments of human adipose tissue were maintained in culture for 1 wee k in a medium containing 1 mU/ml insulin and 100 ng/ml dexamethasone. Under these conditions lipoprotein lipase activity was present in huma n adipose tissue fragments which converted [C-14]glucose to (CO2)-C-14 and [C-14]triglyceride. Both metabolic parameters studied were affect ed by human tumor necrosis factor and brefeldin A, When fragments of h uman adipose tissue after 1 week in culture were incubated with nicoti ne tartrate fbr 20 h, a slight but significant increase in lipoprotein lipase activity was observed, and an increased conversion of [C-14]gl ucose to (CO2)-C-14 and [C-14]triglyceride occurred. Nicotin was taken up by human adipose tissue, but no conversion to cotinine was observe d. Our data demonstrate a direct effect of nicotine on human adipose t issue metabolism. Furthermore, it is suggested that weight loss in smo kers is a multifactorial phenomenon, and one of the important factors to be considered is the direct effect of nicotine within the tissue.