Inflammation, paraoxonase-1 activity and HDL physico-chemical properties: a comparison between Prader-Willi syndrome and obese subjects

Abstract

Summary Prader-Willi syndrome (PWS) represents the most common form of genetic obesity. Several studies confirm that obesity is associated with inflammation, oxidative stress and impairment of antioxidant system, while no data are available concerning PWS subjects. We compared levels of plasma lipids and C-reactive protein (CRP) in 30 normal weight subjects, 15 PWS obese subjects and 13 body mass index-matched obese not affected by PWS. In all subjects we evaluated levels of lipid hydroperoxides and the activity of paraoxonase-1 (PON1), an enzyme involved in the antioxidant and anti-inflammatory properties exerted by high density lipoproteins (HDL). Furthermore using the fluorescent molecule of Laurdan, we investigated the physico-chemical properties of HDL isolated from normal weight and obese patients. Our results demonstrated, for the first time, higher levels of lipid hydroperoxides and a lower PON1 activity in plasma of PWS with respect to controls. These alterations are related with CRP levels with a PON1:CRP ratio lower in PWS compared with non-PWS obese subjects. The study of Laurdan fluorescence parameters showed significant modifications of physico-chemical properties in HDL from PWS. Whatever are the causes of obesity, the increase of adiposity is associated with inflammation, oxidative stress and with alterations of HDL compositional and functional properties.