Depot-specific effects of fatty acids on lipid accumulation in children's adipocytes

Circulating concentrations of fatty acids are elevated in obesity, although their effect on regional fat deposition is relatively unexplored. With the increasing prevalence of childhood obesity, we aimed to investigate whether saturated and unsaturated fatty acids lead to differential lipid accumulation (LA) in children's subcutaneous and visceral adipocytes. To examine this, subcutaneous and peri-nephric pre-adipocytes, isolated from fat biopsies from 6 pre-pubertal children, were differentiated in vitro before being exposed to palmitate and/or oleate for 24 h. Lipid accumulation was then quantified by nile red staining. Palmitate significantly increased LA in visceral adipocytes at all doses > or =188 microM (e.g. Palmitate 750 microM: +30.0%[8.2]; p<0.01), whilst only a dose of 375 microM led to a significant, but smaller, increase in LA in subcutaneous adipocytes (Palmitate 375 micro: +13.0%[4.3]; p=0.02). In contrast, oleate significantly increased LA in subcutaneous (Oleate 1000 microM: +36.3%[14.0]; p=0.01), but not visceral (Oleate 1000 microM: +16.2%[9.6]; p=0.25) adipocytes. These data suggest that saturated and unsaturated fatty acids may exert depot-specific effects on lipid accumulation.