Impact of inflammatory cytokine and adipokine gene variations in the development of HIV-associated lipodystrophy

Role of Proinflammatory Cytokines and Genetic Factors Related to Metabolic Alterations in People Living with HIV/AIDS

Metabolic alterations are a common problem in people living with HIV (PLHIV), as a result of a stage of chronic inflammation that affects the homeostasis of the organism. Prolonged exposure to antiretroviral therapy has been associated with developing lipodystrophies that modify lipoprotein metabolism and inflammatory markers such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), which are mediators of the immune response. The study aimed to associate TNF-α and IL-6 levels with their polymorphisms and metabolic alterations in PLIHV. We hypothesized that TNF-α and IL-6 levels and their polymorphisms are associated with metabolic alterations. In total, 185 PLHIV and 51 HIV-negative people were included. Biochemical parameters were determined by colorimetric assay, cytokine levels by immunoassay, and allelic discrimination by quantitative polymerase chain reaction. A correlation was found between TNF-α levels and the variables cholesterol (r = -0.171, P = 0.020) and high-density lipoprotein (HDL) (r = -0.245, P = 0.001). There are associations between HDL levels (P = 0.011) and GG genotype of rs1800629. The results suggest a metabolic alteration related to the constant immune response, especially the production of proinflammatory cytokines such as TNF-α and IL-6. It was observed that genetic factors may influence metabolism alteration, mainly in lipids.

12-week Dolutegravir treatment marginally reduces energy expenditure but does not increase body weight or alter vascular function in a murine model of Human Immunodeficiency Virus infection

Combination antiretroviral therapy (cART) has markedly increased life expectancy in people with HIV (PWH) but has also resulted in an increased prevalence of cardiometabolic disorders, whose etiopathology remains ill-defined. Notably, the respective contribution of cART and HIV-derived proteins to obesity and vascular alterations remain poorly understood. Therefore, we investigated the individual and combined effects of HIV-proteins and of the integrase strand transfer inhibitor Dolutegravir (DTG) on body composition and vascular reactivity. Male wildtype (WT) and HIV transgenic (Tg26) mice, received DTG or vehicle for 12 weeks. Viral proteins expression in Tg26 mice lowered fat mass, increased heat production, and induced a 2-fold increase in brown adipose tissue (BAT) uncoupling protein 1 (UCP1) expression. DTG increased the expression of markers of adipogenesis in adipocytes in culture, but also reduced heat production and BAT UCP1 and UCP3 expression in Tg26 mice. DTG increased food intake, fat percentage and protected from lean mass reduction in Tg26 mice only. However, DTG did not increase body weight in either WT or Tg26 mice. Viral protein expression reduced acetylcholine (endothelium)-mediated relaxation by 14% in mesenteric arteries preconstricted with phenylephrine. However, DTG did not impair nor improve endothelium-dependent relaxation. Together, these data indicate that DTG's effects on food intake, adipogenesis and energy expenditure are insufficient to increase body weight, even in the presence of HIV-proteins, suggesting that body weight gain in PWH involves additional factors likely including other cART components and pre-existing comorbidities. Moreover, these data rule out DTG as a source of vascular disorders in PWH.