Role of P-glycoprotein in the efflux of raltegravir from human intestinal cells and CD4+ T-cells as an interaction target for anti-HIV agents.

Cellular efflux and uptake transports of several anti-HIV agents are mediated by plasma membrane-localized solute transporters. However, transporters involved in raltegravir disposition have not been fully characterized. Here, we performed in vitro studies to identify transporters mediating transcellular transport of raltegravir. Transepithelial raltegravir transport was examined using porcine kidney epithelial cell line (LLC-PK1) and LLC-PK1 cells stably transfected with P-glycoprotein (also known as Multiple drug resistance 1) (L-MDR1). Transepithelial transport of raltegravir in Caco-2 cell monolayers, and intracellular accumulation of raltegravir in the MT-2 and MT-4 (CD4+ T-) cells were measured in the presence or absence of anti-HIV agents. The uptake of raltegravir was investigated in HEK-293 cells expressing each of several solute carrier family transporters. The apical-to-basal raltegravir transport was significantly decreased in L-MDR1 as compared to that in LLC-PK1 monolayers. In HEK-293 cells expressing breast cancer resistance protein (BCRP), raltegravir accumulation was lower than that in the mock-transfected cells. In Caco-2 cells, protease inhibitors including nelfinavir, ritonavir and lopinavir enhanced the apical-to-basal transport of raltegravir. By contrast, reverse transcriptase inhibitors such as zidovudine, efavirenz, and nevirapine, had no effect on raltegravir transport. The cellular accumulation of raltegravir in MT-2 cells, which express P-glycoprotein, was significantly increased in the presence of protease inhibitors. By contrast, protease inhibitors only marginally increased the accumulation of raltegravir in MT-4 cells, in which P-glycoprotein is not expressed. The present findings suggest that raltegravir is a substrate of both P-glycoprotein and BCRP. Protease inhibitors increase the absorptive transport of raltegravir in Caco-2 cells, and the cellular accumulation in T-cells, at least in part, by P-glycoprotein-mediated interaction.

Treatment Outcome and Adverse Events of Tenofovir Disoproxil Fumarate Based Regimens as Compared to Zidovudine Based Regimens Among People Living with HIV/AIDS: A Systematic Review and Meta-Analysis of Observational Studies.

BACKGROUND: Findings from different studies report inferior clinical and virologic efficacy with TDF/3TC/NVP. But, some studies show that, there was no statistically significant difference in mortality among ZDV and TDF based regimens. The objective of this review was to systematically identify, appraise and synthesize the best available evidence on efficacy and safety of TDF based regimen as compared to ZDV based regimens. METHODS: A three-step search strategy was used to locate published and unpublished studies. First, an initial limited search of google was undertaken followed by analysis of text words. A second extensive search was undertaken. We searched the PubMed, EMBASE, Google Scholar, Medline, and CINHAL. We did the initial search for articles on July 11-18, 2016, and updated the results on May 13, 2017.Third, the reference lists of all identified articles was searched for additional studies. RESULTS: ZDV based regimens had better outcome on prevention of mortality (OR=1.31, 95%CI (1.14, 1.50), I2 = 0%, Chi2 = 2.51), and lower virologic failure (OR = 1.44, 95% CI [1.18, 1.76], chi2 = 5.91, P= 0.003, I2 =83%) while, TDF based regimens were more tolerable (OR=0.15, 95%CI (0.08, 0.30), I2 = 40%, Chi2 = 3.31). The difference in incidence of opportunistic infection is not significant (OR = 0.83, 95% CI [0.52, 1.32], chi2 = 0.11, P= 0.42, I2 =0%). CONCLUSION: There is lower mortality and lower virologic failure in ZDV group, but better safety profile among TDF based regimens.

Anemia among adult HIV patients in Ethiopia: a hospital-based cross-sectional study.

BACKGROUND: Anemia is a major public health problem in HIV patients around the world. It has a negative effect on the quality of life of HIV patients and progression of the HIV disease. In the sub-Saharan African setting, including Ethiopia where both HIV infection and under-nutrition are expected to be high, there is a paucity of data on the matter. This study was aimed to reveal the magnitude and factors associated with anemia among adult HIV patients in Debre-Tabor Hospital, northwest Ethiopia. METHODS: A hospital-based cross-sectional study was used among adult HIV patients in Debre-Tabor Hospital from April 1 to May 30, 2015. The diagnosis of anemia was made following the 2011 World Health Organization recommendation on hemoglobin cut-off points. Univariable and multivariable logistic regression was carried out to assess factors associated with anemia. RESULTS: A total of 377 patients' charts were reviewed. Most of the participants (n=237, 62.9%) were taking antiretroviral treatment (ART). The overall prevalence of anemia was 23% (95% CI: 19.1, 27.6). Being ART-naïve (adjusted odds ratio [AOR]: 3.37; 95% CI: 1.59, 7.14), having treatment history with anti-tuberculosis (TB) drug (AOR: 3.2; 95% CI: 1.19, 8.67), taking zidovudine (ZDV)-containing ART regimen (AOR: 2.14; 95% CI: 1.03, 4.57), and having recent CD4+ T-lymphocytes count of <200 cells/µL (AOR: 2.13; 95% CI: 1.04, 4.36) were associated with occurrence of anemia among adult HIV patients. CONCLUSION AND RECOMMENDATION: Anemia continues to be a major co-morbidity among adult HIV patients in Ethiopia. Adult HIV patients who are taking ZDV-containing ART, with a history of TB treatment, have a low CD4+T-lymphocytes count and are ART-naïve should be carefully screened and treated for anemia.

Evaluation of different antiretroviral drug protocols on naturally infected feline immunodeficiency virus (FIV) cats in the late phase of the asymptomatic stage of infection.

The aim of this study was to evaluate the efficacy of the antiretrovirals: Zidovudine (ZDV) alone; ZDV + Recombinant Human Interferon-α (rHuIFN-α); ZDV + Lamivudine (3TC) and ZDV + valproic acid (Valp) on naturally feline immunodeficiency virus (FIV)-infected cats, in the late phase of the asymptomatic stage of infection. The follow-up was performed over one year, through clinical evaluation and the determination of viral loads and CD4+/CD8+ ratios. Neurological signs were studied by visual and auditory evoked potentials (VEP, AEP) and the responses were abnormal in 80% of the FIV-infected cats. After one year, an improvement in VEP and AEP was observed in the ZDV + Valp group and a worsening in the group receiving ZDV + rHuIFN-α. The CD4+/CD8+ ratio showed a significant increase (both intra and inter-groups) only in ZDV and ZDV + 3TC, between their pre-treatment and one year values, as well as among the other groups. Viral load only showed a significant decrease in ZDV and ZDV + 3TC groups, when comparing the values at one year of treatment vs. pre-treatment values and when the different groups were compared. In addition, the viral load decrease was significantly more pronounced in the ZDV + 3TC vs. ZDV group. We conclude that ZDV and ZDV + 3TC produce significant reductions in viral load and stimulate a recovery of the CD4+/CD8+ ratio, compared with the other protocols. It is clear that the addition of 3TC resulted in a greater reduction in viral load than use of ZDV as a single drug. Therefore, the combination ZDV + 3TC could be more effective than the sole use of ZDV.

Detection of Mutations to Zidovudine in the pol Gene of Human Immunodeficiency Virus-1 by Direct Sequencing

No abstract available.