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1.
J Antimicrob Chemother ; 79(2): 370-374, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38153245

RESUMO

BACKGROUND: Islatravir is a new antiretroviral drug that inhibits the reverse transcriptase (RT) of HIV-1 through multiple mechanisms. It is proposed to be used in combination with doravirine, a new NNRTI. M184V/I mutations have been shown to reduce the in vitro antiviral activity of islatravir, but their effect when pre-selected during ART has not been investigated. METHODS: HIV-1 rt sequences were obtained from four individuals of the Garrahan HIV cohort prior to, or during virological failure to ART. HIV-1 infectious molecular clones were constructed on an NL4-3 backbone, and infectious viruses were produced by transfection of 293T cells. Fold-changes in IC50 were calculated for each mutant versus the NL4-3 WT. HIV-1 phenotypic drug resistance was tested in vitro against NRTIs and NNRTIs. RESULTS: In all the cases, M184I/V, either alone or in the presence of other mutations, was associated with reduced susceptibility to islatravir, abacavir and lamivudine. Viruses carrying M184V/I showed variable levels of resistance to islatravir (4.8 to 33.8-fold). The greatest reduction in susceptibility was observed for viruses carrying the mutations M184V + V106I (33.8-fold resistance) or M184V + I142V (25.2-fold resistance). For NNRTIs, the presence of V106I alone did not affect susceptibility to doravirine or etravirine, but showed a modest reduction in susceptibility to efavirenz (6-fold). Susceptibility to doravirine was slightly reduced only for one of the mutants carrying V106I in combination with Y181C and M184V. CONCLUSIONS: Mutations and polymorphisms selected in vivo together with M184V/I depend on the viral genetic context and on ART history, and could affect the efficacy of islatravir once available for use in the clinic.


Assuntos
Fármacos Anti-HIV , Desoxiadenosinas , Infecções por HIV , HIV-1 , Humanos , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , HIV-1/genética , Infecções por HIV/tratamento farmacológico , Lamivudina/uso terapêutico , Mutação , Transcriptase Reversa do HIV/genética , Farmacorresistência Viral/genética , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico
2.
Viruses ; 15(11)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38005911

RESUMO

Antiretroviral Therapy (ART) is an effective treatment for human immunodeficiency virus (HIV) which has transformed the highly lethal disease, acquired immunodeficiency syndrome (AIDS), into a chronic and manageable condition. However, better methods need to be developed for enhancing patient access and adherence to therapy and for improving treatment in the long term to reduce adverse effects. From the perspective of drug discovery, one promising strategy is the development of anti-HIV prodrugs. This approach aims to enhance the efficacy and safety of treatment, promoting the development of more appropriate and convenient systems for patients. In this review, we discussed the use of the prodrug approach for HIV antiviral agents and emphasized nucleoside reverse transcriptase inhibitors. We comprehensively described various strategies that are used to enhance factors such as water solubility, bioavailability, pharmacokinetic parameters, permeability across biological membranes, chemical stability, drug delivery to specific sites/organs, and tolerability. These strategies might help researchers conduct better studies in this field. We also reported successful examples from the primary therapeutic classes while discussing the advantages and limitations. In this review, we highlighted the key trends in the application of the prodrug approach for treating HIV/AIDS.


Assuntos
Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , Pró-Fármacos , Humanos , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Pró-Fármacos/farmacologia , Nucleosídeos/uso terapêutico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , HIV , Transcriptase Reversa do HIV
3.
J Biomol Struct Dyn ; 41(5): 1715-1729, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34996334

RESUMO

Acquired Immune Deficiency Syndrome (AIDS) is an infectious disease caused by Human Immunodeficiency Virus (HIV) infection and its replication requires the Reverse Transcriptase (RT) enzyme. RT plays a key role in the HIV life cycle, making it one of the most important targets for designing new drugs. Thus, in order to increase therapeutic options against AIDS, halolactone derivatives (D-halolactone) that have been showed as potential non-nucleoside inhibitors of the RT enzyme were studied. In the present work, a series of D-halolactone were investigated by molecular modeling studies, combining Three-dimensional Quantitative Structure-Activity Relationship (3 D-QSAR), molecular docking and Molecular Dynamics (MD) techniques, to understand the molecular characteristics that promote biological activity. The internal and external validation parameters indicated that the 3 D-QSAR model has good predictive capacity and statistical significance. Contour maps provided useful information on the structural characteristics of compounds for anti-HIV-1 activity. The docking results showed that D-halolactone present good complementarity by the RT allosteric site. In MD simulations it was observed that the formation of enzyme-ligand complexes were favorable, and from the free energy decomposition it was found that Leu100, Val106, Tyr181, Try188, and Trp229 are key residues for stabilization in the enzymatic site. Thus, the results showed that the proposed models can be used to design promising HIV-1 RT inhibitors. Communicated by Ramaswamy H. Sarma.


Assuntos
Transcriptase Reversa do HIV , Inibidores da Transcriptase Reversa , Humanos , Síndrome da Imunodeficiência Adquirida , HIV/metabolismo , Transcriptase Reversa do HIV/antagonistas & inibidores , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/química
4.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069929

RESUMO

The success of antiretroviral treatment (ART) is threatened by the emergence of drug resistance mutations (DRM). Since Brazil presents the largest number of people living with HIV (PLWH) in South America we aimed at understanding the dynamics of DRM in this country. We analyzed a total of 20,226 HIV-1 sequences collected from PLWH undergoing ART between 2008-2017. Results show a mild decline of DRM over the years but an increase of the K65R reverse transcriptase mutation from 2.23% to 12.11%. This increase gradually occurred following alterations in the ART regimens replacing zidovudine (AZT) with tenofovir (TDF). PLWH harboring the K65R had significantly higher viral loads than those without this mutation (p < 0.001). Among the two most prevalent HIV-1 subtypes (B and C) there was a significant (p < 0.001) association of K65R with subtype C (11.26%) when compared with subtype B (9.27%). Nonetheless, evidence for K65R transmission in Brazil was found both for C and B subtypes. Additionally, artificial neural network-based immunoinformatic predictions suggest that K65R could enhance viral recognition by HLA-B27 that has relatively low prevalence in the Brazilian population. Overall, the results suggest that tenofovir-based regimens need to be carefully monitored particularly in settings with subtype C and specific HLA profiles.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/genética , Adenina/uso terapêutico , Adulto , Idoso , Fármacos Anti-HIV/farmacologia , Brasil/epidemiologia , Farmacorresistência Viral/fisiologia , Feminino , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/genética , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Tenofovir/uso terapêutico , Falha de Tratamento , Carga Viral/efeitos dos fármacos , Zidovudina/uso terapêutico
5.
Mol Biol Evol ; 38(3): 1184-1198, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33064823

RESUMO

A number of evolutionary hypotheses can be tested by comparing selective pressures among sets of branches in a phylogenetic tree. When the question of interest is to identify specific sites within genes that may be evolving differently, a common approach is to perform separate analyses on subsets of sequences and compare parameter estimates in a post hoc fashion. This approach is statistically suboptimal and not always applicable. Here, we develop a simple extension of a popular fixed effects likelihood method in the context of codon-based evolutionary phylogenetic maximum likelihood testing, Contrast-FEL. It is suitable for identifying individual alignment sites where any among the K≥2 sets of branches in a phylogenetic tree have detectably different ω ratios, indicative of different selective regimes. Using extensive simulations, we show that Contrast-FEL delivers good power, exceeding 90% for sufficiently large differences, while maintaining tight control over false positive rates, when the model is correctly specified. We conclude by applying Contrast-FEL to data from five previously published studies spanning a diverse range of organisms and focusing on different evolutionary questions.


Assuntos
Técnicas Genéticas , Filogenia , Seleção Genética , Brassicaceae/genética , Citocromos b/genética , Transcriptase Reversa do HIV/genética , Haemosporida/genética , Rodopsina/genética , Ribulose-Bifosfato Carboxilase/genética , Tricomas/genética
6.
AIDS Res Hum Retroviruses ; 37(7): 557-565, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33287618

RESUMO

HIV drug resistance testing is fundamental in clinical patient management, but data on HIV-1 drug-resistant mutations (DRMs) is scarce in the Caribbean and in Suriname limited to one survey on transmitted resistance. The aim of this study was to address this gap, to gain insight in acquired HIV drug resistance (ADR) prevalence and mutation patterns, and to improve HIV-1 treatment outcome of people living with HIV (PLHIV) in Suriname. A prospective cross-sectional study was conducted from July 2018 through January 2019 among treatment-experienced PLHIV (n = 72), with either treatment failure or antiretroviral therapy restart. Genotypic drug resistance testing was performed and DRM impact on drug effectiveness was examined. Genotypic drug resistance testing revealed 97.2% HIV-1 subtype B, 2.8% B/D recombinants and a ADR prevalence of 63.2% in treatment failure patients, with a predominance of nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations. The most common DRMs were M184V (23.6%) and K103N (18.8%). A high level of non-DRM polymorphisms was observed in both the reverse transcriptase (RT) and protease (PR) gene. Interesting deviations from the existing mutation datasets were noted at position E248 and R83 of the RT gene and L63 and V77 in the PR gene. Full susceptibility to all examined drugs was 54.2%, while high-level drug resistance was estimated at 37.5%, which seems promising for treatment outcomes for PLHIV in Suriname, although cross-resistance to next-generation NNRTIs was already estimated for nearly a quarter of the patients. The meager 2.9% of PR DRMs rendered protease inhibitors as an effective rescue HIV-1 treatment.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Farmacorresistência Viral/genética , Genótipo , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV , HIV-1/genética , Humanos , Mutação , Estudos Prospectivos , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Suriname
7.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32747359

RESUMO

In HIV-1, development of resistance to AZT (3'-azido-3'-deoxythymidine) is mediated by the acquisition of thymidine analogue resistance mutations (TAMs) (i.e., M41L, D67N, K70R, L210W, T215F/Y, and K219E/Q) in the viral reverse transcriptase (RT). Clinically relevant combinations of TAMs, such as M41L/T215Y or D67N/K70R/T215F/K219Q, enhance the ATP-mediated excision of AZT monophosphate (AZTMP) from the 3' end of the primer, allowing DNA synthesis to continue. Additionally, during HIV-1 maturation, the Gag polyprotein is cleaved to release a mature nucleocapsid protein (NCp7) and two intermediate precursors (NCp9 and NCp15). NC proteins interact with the viral genome and facilitate the reverse transcription process. Using wild-type and TAM-containing RTs, we showed that both NCp9 and NCp15 inhibited ATP-mediated rescue of AZTMP-terminated primers annealed to RNA templates but not DNA templates, while NCp7 had no effect on rescue activity. RNase H inactivation by introducing the active-site mutation E478Q led to the loss of the inhibitory effect shown by NCp9. NCp15 had a stimulatory effect on the RT's RNase H activity not observed with NCp7 and NCp9. However, analysis of RNase H cleavage patterns revealed that in the presence of NCp9, RNA/DNA complexes containing duplexes of 12 bp had reduced stability in comparison with those obtained in the absence of NC or with NCp7 or NCp15. These effects are expected to have a strong influence on the inhibitory action of NCp9 and NCp15 by affecting the efficiency of RNA-dependent DNA polymerization after unblocking DNA primers terminated with AZTMP and other nucleotide analogues.


Assuntos
Fármacos Anti-HIV , Zidovudina , Trifosfato de Adenosina , Fármacos Anti-HIV/farmacologia , Transcriptase Reversa do HIV/genética , Mutação , Precursores de Proteínas , Inibidores da Transcriptase Reversa/farmacologia , Zidovudina/farmacologia
8.
Eur J Med Chem ; 194: 112255, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244098

RESUMO

Human immunodeficiency virus type 1 (HIV-1) is a public health problem that affects over 38 million people worldwide. Although there are highly active antiretroviral therapies, emergence of antiviral resistant strains is a problem which leads to almost a million death annually. Thus, the development of new drugs is necessary. The viral enzyme reverse transcriptase (RT) represents a validated therapeutic target. Because the oxoquinolinic scaffold has substantial biological activities, including antiretroviral, a new series of 4-oxoquinoline ribonucleoside derivatives obtained by molecular hybridization were studied here. All synthesized compounds were tested against human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT), and 9a and 9d displayed the highest antiviral activities, with IC50 values of 1.4 and 1.6 µM, respectively. These compounds were less cytotoxic than AZT and showed CC50 values of 1486 and 1394 µM, respectively. Molecular docking studies showed that the most active compounds bound to the allosteric site of the enzyme, suggesting a low susceptibility to the development of antiviral resistance. In silico pharmacokinetic and toxicological evaluations reinforced the potential of the active compounds as anti-HIV candidates for further exploration. Overall, this work showed that compounds 9a and 9d are promising scaffold for future anti-HIV-1 RT drug design.


Assuntos
4-Quinolonas/farmacologia , Fármacos Anti-HIV/farmacologia , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Ribonucleosídeos/farmacologia , 4-Quinolonas/síntese química , 4-Quinolonas/química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Relação Dose-Resposta a Droga , Desenho de Fármacos , Transcriptase Reversa do HIV/metabolismo , HIV-1/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/química , Ribonucleosídeos/síntese química , Ribonucleosídeos/química , Relação Estrutura-Atividade
9.
Eur J Med Chem ; 188: 111987, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31893549

RESUMO

Infection by human immunodeficiency virus still represents a continuous serious concern and a global threat to human health. Due to appearance of multi-resistant virus strains and the serious adverse side effects of the antiretroviral therapy administered, there is an urgent need for the development of new treatment agents, more active, less toxic and with increased tolerability to mutations. Quinoxaline derivatives are an emergent class of heterocyclic compounds with a wide spectrum of biological activities and therapeutic applications. These types of compounds have also shown high potency in the inhibition of HIV reverse transcriptase and HIV replication in cell culture. For these reasons we propose, in this work, the design, synthesis and biological evaluation of quinoxaline derivatives targeting HIV reverse transcriptase enzyme. For this, we first carried out a structure-based development of target-specific compound virtual chemical library of quinoxaline derivatives. The rational construction of the virtual chemical library was based on previously assigned pharmacophore features. This library was processed by a virtual screening protocol employing molecular docking and 3D-QSAR. Twenty-five quinoxaline compounds were selected for synthesis in the basis of their docking and 3D-QSAR scores and chemical synthetic simplicity. They were evaluated as inhibitors of the recombinant wild-type reverse transcriptase enzyme. Finally, the anti-HIV activity and cytotoxicity of the synthesized quinoxaline compounds with highest reverse transcriptase inhibitory capabilities was evaluated. This simple screening strategy led to the discovery of two selective and potent quinoxaline reverse transcriptase inhibitors with high selectivity index.


Assuntos
Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Quinoxalinas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Quinoxalinas/síntese química , Quinoxalinas/química , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/química , Relação Estrutura-Atividade
10.
Curr HIV Res ; 17(5): 350-359, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31622220

RESUMO

BACKGROUND: The diversity of the HIV proteome influences the cellular response and development of an effective vaccine, particularly due to the generation of viral variants with mutations located within CD8+ T-cell epitopes. These mutations can affect the recognition of the epitopes, that may result in the selection of HIV variants with mutated epitopes (autologous epitopes) and different CD8+ T-cell functional profiles. OBJECTIVE: To determine the phenotype and functionality of CD8+ T-cell from HIV-infected Colombian patients in response to autologous and consensus peptides derived from HIV-1 clade B protease and reverse transcriptase (RT). METHODS: By flow cytometry, we compared the ex vivo CD8+ T-cell responses from HIV-infected patients to autologous and consensus peptides derived from HIV-1 clade B protease and RT, restricted by HLA-B*35, HLA-B*44 and HLA-B*51 alleles. RESULTS: Although autologous peptides restricted by HLA-B*35 and HLA-B*44 did not show any differences compared with consensus peptides, we observed the induction of a higher polyfunctional profile of CD8+ T-cells by autologous peptides restricted by HLA-B*51, particularly by the production of interferon-γ and macrophage inflammatory protein-1ß. The response by different memory CD8+ T-cell populations was comparable between autologous vs. consensus peptides. In addition, the magnitude of the polyfunctional response induced by the HLA-B*51-restricted QRPLVTIRI autologous epitope correlated with low viremia. CONCLUSION: Autologous peptides should be considered for the evaluation of HIV-specific CD8+ Tcell responses and to reveal some relevant epitopes that could be useful for therapeutic strategies aiming to promote polyfunctional CD8+ T-cell responses in a specific population of HIV-infected patients.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Antígenos HIV/imunologia , Infecções por HIV/imunologia , Protease de HIV/imunologia , Transcriptase Reversa do HIV/imunologia , HIV-1/imunologia , Fatores Imunológicos/análise , Adulto , Linfócitos T CD8-Positivos/química , Estudos de Coortes , Colômbia , Feminino , Citometria de Fluxo , Genótipo , HIV-1/classificação , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade
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