HIV infection and high density lipoprotein metabolism

HIV infection and its treatment are associated with dyslipidemia, including hypoalphalipoproteinemia, and increased risk of cardiovascular disease. Parameters of HDL metabolism in HIV-positive patients were investigated in a cross-sectional study. The following groups of subjects were selected: (i) 25 treatment-naïve HIV-infected patients or HIV-infected patients on long therapy break, (ii) 28 HIV-infected patients currently treated with protease inhibitors, and (iii) 33 HIV-negative subjects. Compared to the HIV-negative group, all groups of HIV-infected patients were characterized by significantly elevated triglyceride and apolipoprotein B levels, mass and activity of lecithin cholesterol acyl transferase and cholesteryl ester transfer protein (p<0.01). Total and LDL cholesterol was lower in treatment-naïve HIV-infected group only. HDL cholesterol and prebeta(1)-HDL were significantly lower in all HIV-infected groups (p<0.05), while mean levels of apolipoprotein A-I (apoA-I) and ability of plasma to promote cholesterol efflux were similar in all groups. We found a positive correlation between apoA-I and levels of CD4+ cells (r(2)=0.3, p<0.001). Plasma level of phospholipid transfer protein was reduced in the group on antiretroviral therapy. Taken together these results suggest that HIV infection is associated with modified HDL metabolism re-directing cholesterol to the apoB-containing lipoproteins and likely reducing the functionality of reverse cholesterol transport.