To evaluate the possibility of copy number variation (CNV) of CYP2B6.
We investigated CNV in 226 HIV-1-infected individuals by quantitative PCR. Identification of a candidate CNV prompted ...characterization of the size of deletion by assessment of absence of exons, mapping of the recombination site by sequencing, and by southern blot. The functional consequences of CNV were assessed in silico (predicted protein), and in vivo, by evaluation of plasma drug levels of the CYP2B6 substrate efavirenz.
Analyses identified one white individual carrying a heterozygous deletion of exons 1-4 of CYP2B6. We identified a approximately 68 kb deletion between CYP2B7 and CYP2B6, and mapped the crossover to a homologous region in intron 4 of both genes. The new hybrid allele, named CYP2B6*29, carries two amino acid substitutions, Q172H and M198T, previously associated with impaired enzyme function. Consistent with the functional prediction, the average of efavirenz area under the curve values of the patient was mean+/-SD, 81.64+/-23.62, versus 47.75+/-19.73 mug h/ml for individuals with an extensive metabolizer phenotype.
CYP2B6*29 represents a new mechanism of genetic variation at the CYP2B6 locus, underscoring the highly polymorphic nature of this isoenzyme.
Changes in body fat distribution in virologically suppressed HIV-infected patients switching from lopinavir/ritonavir (LPV/r) to atazanavir/ritonavir (ATV/r) were assessed. A prospective comparative ...study was conducted of 37 patients receiving LPV/r regimens switching to ATV/r with 46 patients continuing with LPV/r. Body composition was assessed with whole-body dual-energy x-ray absorptiometry (DXA). Abdominal CT scans were also performed in a subset of patients. Groups were comparable in baseline demographic, clinical, and anthropometric characteristics. After 12 months, peripheral fat did not change significantly, but an increase in trunk fat was observed only in the ATV/r group (0.87 kg, p = 0.021). The percentage of patients with an increase ≥20% in total fat was 37.8% and 15.2% in the ATV/r and LPV/r groups, respectively (p = 0.018). In the ATV/r group, the increase in trunk fat (9.4%) was significantly higher than in peripheral fat (3.7%) (p = 0.007), leading to a significant increase in fat mass ratio (3.76%, p = 0.028), whereas no significant differences were found among LPV/r patients. CT scans showed that abdominal fat increase corresponded to both visceral (28%, p = 0.008) and subcutaneous fat (42%, p = 0.008). These data suggest that switching from LPV/r to ATV/r is associated with increased trunk fat, both subcutaneous and visceral.
To study if progression to AIDS and death, as well as clinical and virological response to highly active antiretroviral therapy (HAART), differs between men and women.
We studied a multicenter, ...hospital-based cohort of HIV-infected patients attending 10 hospitals in Spain from January 1997 to December 2003. Kaplan-Meier and Cox regression were used to assess the effect of sex on time to AIDS, survival from AIDS, onset of a new AIDS event or death, and viral suppression from HAART.
Of 4643 patients, 27% were women. Women had statistically significant lower viral loads (VL) of 3.9 vs. 4.1 log10/mL (p = 0.02) and higher median CD4 counts of 339 vs. 288 cells/mm3 (p < 0.001) at entry and were more likely to be AIDS free at entry. In univariate analysis, women seemed to show a nonsignificant lower progression to AIDS (HR 0.88) (95 CI% 0.73-1.07), which disappeared in multivariate analyses (HR 1.03) (95% CI 0.82-1.29). Survival from AIDS seemed to be higher in women (HR 0.65) (95% CI 0.40-1.05), but differences became clearly nonsignificant after adjustments (HR 0.71) (95% CI 0.42-1.23). No differences were seen in time to new AIDS condition or death after HAART (HR 1.08) (95% CI 0.80-1.46) in multivariate analyses. No differences were seen for time to VL suppression after initiation of HAART (HR 1.07) (95% CI 0.92-1.24).
We have found no differences in HIV progression and response to HAART attributable to gender among patients accessing the Spanish hospital network.
Mitochondrial parameters in peripheral blood mononuclear cells (PBMC) and their relationship with mitochondrially-driven PBMC apoptosis were investigated in a group of HIV-1-infected long-term ...nonprogressors (LTNP) and compared with untreated asymptomatic HIV-1 infected typical progressors (TP) and uninfected healthy controls (HC). Twenty-six LTNP, 27 TP and 31 HC were evaluated. Studies were performed in PBMCs. Mitochondrial DNA content (mtDNA) was assessed by quantitative real-time PCR. Activities of mitochondrial respiratory chain complexes (MRC) II, III and IV were determined by spectrophotometry. Caspase-3 activity was assessed by fluorimetry, and caspase-9 activation and Bcl-2 levels were assessed by immunoblotting. mtDNA abundance (p<0.05), MRC complex II (p<0.001), complex III (p<0.01) and complex IV (p=0.01) were lower in the TP group than in the HC group. In the LTNP group these parameters were similar to those of the HC group except for complex II, which was decreased (p<0.01). The PBMC of TP showed the highest overall apoptotic activation, since their caspase-3 activity was greater than that of HC (p<0.05) and LTNP. In the case of LTNP, however, the difference was non-significant. Caspase-9 and the caspase-9/Bcl-2 ratio were both over-expressed in TP compared to HC (p<0.01) and LTNP (p<0.05). Both of these measurements indicate that mitochondrially-driven apoptosis in TP is greater than in LTNP and HC. A relationship between mitochondrial damage and apoptotic activation was found in TP. Mitochondrial damage is associated with increased PBMC apoptosis in patients with active HIV-1 replication (TP). These abnormalities are slight or not present in LTNP.
To examine whether polymorphisms of the RANTES chemokine gene promoter are associated with long-term nonprogressive HIV-1 infection in white Spanish subjects, we performed a cross-sectional genetic ...association case-control study. Two-hundred sixty-seven white Spaniards were studied: 58 were HIV-1-infected long-term nonprogressors (LTNPs) of more than 16 years, 109 were HIV-1-infected usual progressors (UPs), and 100 were control subjects. Three RANTES single nucleotide polymorphisms (SNPs) at positions -28C>G, -109T>C, and -403G>A were assessed. The prevalence of the CCR5Delta 32 allele was also examined. Genotyping was performed using polymerase chain reaction and automatic sequencing analysis methods. Genotype and allele frequencies between the 3 groups were compared by the chi2 test and the Fisher exact test. The distribution of allelic variants of RANTES in controls, UPs, and LTNPs, respectively, was 3%, 2%, and 5% for -28G; 4%, 2%, and 2% for -109C; and 18%, 18%, and 18% for -403A (P = not significant). The differences were still nonsignificant when we exclusively analyzed individuals not carrying the CCR5Delta32 allele. We conclude that LTNP of more than 16 years is not associated with SNPs in the RANTES gene promoter in white Spanish HIV-1-infected subjects.
The objective of this study was to determine the impact of tenofovir or abacavir discontinuation on low-density lipoprotein (LDL) phenotype and lipoprotein-associated phospholipase A2 (Lp-PLA2) ...activity in HIV-infected patients treated with lopinavir/ritonavir plus 2 nucleos(t)ide reverse transcriptase inhibitors (NRTI).
Multicenter, open-label study. Patients were randomized to continue with lopinavir/ritonavir plus 2 NRTI (triple therapy) or to switch to lopinavir/ritonavir plus lamivudine (dual therapy). LDL phenotype (by gradient gel electrophoresis) and Lp-PLA2 (by 2-thio-PAF) were determined at baseline and week 48.
Forty-four patients included (triple therapy n = 19, dual therapy n = 25): men 63.6%, age 41.5 years (25-61), Framingham score 4.9% (0.2-22). Tenofovir was part of the regimen in 28 (63.6%) patients. Dual therapy patients were younger (p = 0.013) and had lower baseline apolipoprotein A1 (p = 0.029). At week 48, there were no changes in standard lipid measurements, except ApoA1/Apo B, which increased in dual therapy (p = 0.038) with no differences between arms. At week 48, no change in LDL phenotype was found in either arm. No changes in total Lp-PLA2 activity or the relative distribution of LDL and HDL particles were found at week 48 in either arm.
Discontinuing the third nucleos(t)ide, mainly tenofovir and abacavir, in a lopinavir/ritonavir-containing regimen was not associated with a deleterious effect on LDL phenotype nor in Lp-PLA2 activity.
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