Correlation of APOE polymorphism, expression, and plasma levels with cardiac comorbidities among lipodystrophy in HIV-infected patients

Abstract

Lipodystrophy in HIV-infected patients (LDHIV) includes morphological and metabolic abnormalities, including lipid and glucose metabolism. ApoE plays a role in the transport and clearance of lipoprotein. In the general population, ApoE 112 (rs429358) and 158 (rs7412) polymorphisms were linked to severe dyslipidemia. Therefore, we investigated ApoE polymorphism using PCR-RFLP in 200 HIV patients (100 with HIV-associated lipodystrophy (HIVLD), 100 without HIVLD), as well as 100 healthy controls. We also assessed ApoE expression using qRT-PCR and measured its level using ELISA. The APOE 4/4, 3/4, and 2/4 genotypes have been associated with a decreased risk of HIV-1 infection. (P = 0.0001, OR = 0.18; P = 0.006, OR = 0.87; P = 0.006, OR = 0.09) when compared between HIV-positive individuals and healthy controls. Conversely, APOE allele 2 was linked to a higher risk of acquiring HIV-1 (P = 0.03, OR = 3.02). APOE allele 2 was linked to a higher likelihood of HIVLD severity when compared between patients with and without HIVLD (P = 0.05, OR = 2.82). When comparing patients with HIVLD to healthy controls, the APOE 4/4 and 2/4 genotypes as well as allele 4 were linked with the reduced risk of LDHIV (P = 0.0006, OR = 0.21; P = 0.01, OR = 0.18; P = 0.0002, OR = 0.40). When compared to patients without HIVLD from healthy controls, the ApoE 4/4 genotype, 2 and 4 alleles, were linked to a reduced risk of developing HIVLD (P = 0.0009, OR = 0.14; P = 0.0001, OR = 0.17; P = 0.00001, OR = 0.39). When comparing impaired to normal cholesterol levels in patients without HIVLD, the ApoE 3/4 genotype was linked with the increased risk of impaired cholesterol levels (P = 0.02, OR = 3.37). When comparing impaired and normal glucose levels in patients without HIVLD, the ApoE 4/4 genotype was associated to an elevated risk of impaired glucose levels (P = 0.03, OR = 8.27). In multivariate analysis, independent impaired cholesterol, LDL, and glucose levels were associated with a higher risk of lipodystrophy severity (P = 0.04, OR = 2.33; P = 0.001, OR = 4.05; P = 0.05, OR = 2.63). ApoE expression was up-regulated in LDHIV with a fold change value of 4.02 compared to those without HIVLD. ApoE protein level was found to be higher in patients of the HIVLD group (3.01 mg/dL) compared to those without HIVLD group (2.83 mg/dL). In conclusion, individuals with ApoE allele 2 were at higher risk for HIV-1 acquisition and severity of HIVLD, whereas those with ApoE allele 4 were at reduced HIVLD severity and development risk. It’s possible that ApoE’s increased level and its overexpression are related to the ApoE allele 2 in HIVLD patients. The development of LDHIV may be facilitated by the APOE 3/4 and 4/4 genotypes as well as abnormal glucose and cholesterol levels.