Inflammation-modulating cytokine profile and lipid interaction in HIV-related risk factors for cardiovascular diseases

HIV infection and antiretroviral therapy (ART) are associated with changes in plasma levels of lipoproteins, thus posing the risk of cardiovascular complications in infected individuals. The alteration in plasma lipoprotein levels results from dysregulation of inflammation-modulating cytokines that control lipid metabolism. Little is understood regarding the relationship between the cytokines and serum lipid levels, which have been reported to be altered in adults receiving ART. The objective of this study was to describe the profiles of inflammation-modulating cytokines and their relationship to lipids as cardiovascular disease (CVD) risk factors in HIV infection. This observational cross-sectional study measured plasma levels of interleukin (IL)-10, tumor necrosis factor-alpha (TNF)-alpha, IL-4, total cholesterol (TC), and high-density lipoprotein cholesterol (HDL-c) in HIV-infected and uninfected adults. A total of 219 HIV-infected participants were enrolled from an HIV treatment center; of them, 187 were receiving ART and 32 were ART naive, while 65 were HIV-uninfected blood donors. HIV-infected individuals had higher levels of IL-10 (HIV-infected ART-naive [P= 0.0024] and ART-receiving [P= 0.033]) than their uninfected counterparts. ART-naive subjects had significantly higher plasma levels of IL-10 than ART-receiving subjects (P= 0.0014). No significant difference was observed in plasma levels of IL-4 and TNF-alpha across the three groups. Regarding plasma lipoproteins, HDL-c levels were reduced in HIV ART-naive (P= 0.002) and ART-receiving (P= 0.015) subjects compared to HIV-uninfected subjects. Similarly, TC levels were lower in the HIV-infected than in the HIV-uninfected group regardless of whether the patients were undergoing ART or not (P<0.001). IL-10 levels correlated with TC levels in the HIV-uninfected group but not in the HIV-infected groups. Levels of HDL-c were reduced, while IL-10 plasma concentrations were elevated in HIV-infected individuals. A correlation observed in HIV-uninfected individuals between anti-inflammatory cytokine IL-10 and TC was lost in HIV-infected individuals. Clinical significance of these differences needs to be ascertained with respect to HIV-related CVD risk.