Background and aims: Aging is associated with an increased risk of developing atherosclerosis. Subjects over 80 years of age without cardiovascular disease provide a model to investigate the protective factors increasing their resistance to atherosclerotic disease. Platelet-activating factor acetylhydrolase (PAF-AH) is an enzyme associated with low density lipoprotein (LDL) and high density lipoprotein (HDL) inactivating platelet-activating factor (PAF) and preventing LDL oxidation by hydrolysis of oxidized phospholipids. The aim of the present study was to evaluate the contribution of the PAFAH gene Arg92His, Ile198Thr and Ala379Val polymorphisms to resistance toward developing cardiovascular events in healthy Sicilian octogenarians.
Methods: Distribution of PAF-AH genotypes and activity, and biochemical parameters, were compared between 100 octogenarians and 200 healthy adults.
Results: The individuals in the elderly group displayed significantly higher levels of HDL-C (p<0.001) and plasma (p<0.001) and HDL (p<0.001) PAF-AH activity. Analysis of PAFAH genotype distributions showed no significant differences between octogenarians and controls. No differences among PAF-AH genotypes with respect to plasma and HDL PAF-AH activity were found in either group.
Conclusions: Our results provide no evidence of a significant association between the PAF-AH gene Arg92His, Ile198Thr and Ala379Val polymorphisms and successful aging in Sicilians. They also emphasize that, in these subjects, aging is characterized by increased levels of PAF-AH activity and HDL-C.