Effects of weight loss on PLTP activity and HDL particle size

Dyslipidaemia in obesity is characterized by hypertriglyceridaemia, low HDL-C levels, small, dense HDL particles and increased phospholipid transfer protein (PLTP) activity.

In the present study, we investigated PLTP activity and HDL particle size in 16 morbidly obese, middle-aged women, who underwent Swedish Adjustable Gastric Banding surgery. Study subjects were tested within 2 months before and 1 y after surgery. PLTP activity was determined by exogenous substrate assay and HDL particle size by gradient gel electrophoresis, respectively.

Pronounced weight loss after gastric banding surgery resulted in a significant decrease of PLTP activity from 8.42+/-2.04 to 7.43+/-2.21 micromol/ml/h (P=0.02). The size of HDL(2) particles increased signficantly from 14.04+/-0.86 to 14.28+/-0.64 nm (P=0.02) after body weight reduction, while no change in HDL(3) particle size was apparent.

Our results suggest that dyslipidaemia in obesity is--at least partially--reversible by weight loss. We hypothesize that reduction of PLTP activity and increase of HDL particle size are important component factors in converting the atherogenic lipoprotein profile of obese subjects into a less atherogenic profile with weight loss.