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1.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443358

RESUMO

Plants are the everlasting source of a wide spectrum of specialized metabolites, characterized by wide variability in term of chemical structures and different biological properties such antiviral activity. In the search for novel antiviral agents against Human Immunodeficiency Virus type 1 (HIV-1) from plants, the phytochemical investigation of Scrophularia trifoliata L. led us to isolate and characterize four flavonols glycosides along with nine iridoid glycosides, two of them, 5 and 13, described for the first time. In the present study, we investigated, for the first time, the contents of a methanol extract of S. trifoliata leaves, in order to explore the potential antiviral activity against HIV-1. The antiviral activity was evaluated in biochemical assays for the inhibition of HIV-1Reverse Transcriptase (RT)-associated Ribonuclease H (RNase H) activity and HIV-1 Integrase (IN). Three isolated flavonoids, rutin, kaempferol-7-O-rhamnosyl-3-O-glucopyranoside, and kaempferol-3-O-glucopyranoside, 8-10, inhibited specifically the HIV-1 IN activity at submicromolar concentration, with the latter being the most potent, showing an IC50 value of 24 nM.


Assuntos
Flavonóis/química , Flavonóis/farmacologia , HIV-1/efeitos dos fármacos , Iridoides/química , Iridoides/farmacologia , Scrophularia/química , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Concentração Inibidora 50 , Folhas de Planta/química
2.
Viruses ; 13(7)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34372560

RESUMO

The combination of the two nucleoside reverse transcriptase inhibitors (NRTI) tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) is used in most highly active antiretroviral therapies for treatment of HIV-1 infection, as well as in pre-exposure prophylaxis against HIV acquisition. Administered as prodrugs, these drugs are taken up by HIV-infected target cells, undergo intracellular phosphorylation and compete with natural deoxynucleoside triphosphates (dNTP) for incorporation into nascent viral DNA during reverse transcription. Once incorporated, they halt reverse transcription. In vitro studies have proposed that TDF and FTC act synergistically within an HIV-infected cell. However, it is unclear whether, and which, direct drug-drug interactions mediate the apparent synergy. The goal of this work was to refine a mechanistic model for the molecular mechanism of action (MMOA) of nucleoside analogues in order to analyse whether putative direct interactions may account for the in vitro observed synergistic effects. Our analysis suggests that depletion of dNTP pools can explain apparent synergy between TDF and FTC in HIV-infected cells at clinically relevant concentrations. Dead-end complex (DEC) formation does not seem to significantly contribute to the synergistic effect. However, in the presence of non-nucleoside reverse transcriptase inhibitors (NNRTIs), its role might be more relevant, as previously reported in experimental in vitro studies.


Assuntos
Emtricitabina/uso terapêutico , HIV-1/efeitos dos fármacos , Tenofovir/uso terapêutico , Fármacos Anti-HIV/farmacologia , Terapia Antirretroviral de Alta Atividade/métodos , Desoxicitidina/análogos & derivados , Quimioterapia Combinada/métodos , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/genética , HIV-1/patogenicidade , Humanos , Modelos Teóricos , Profilaxia Pré-Exposição/métodos , Transcrição Reversa/efeitos dos fármacos , Tenofovir/metabolismo
3.
Int J Mol Sci ; 22(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34445073

RESUMO

Human immunodeficiency virus (HIV-1) is still a major problem, not only in developing countries but is also re-emerging in several developed countries, thus the development of new compounds able to inhibit the virus, either for prophylaxis or treatment, is still needed. Nanotechnology has provided the science community with several new tools for biomedical applications. G2-S16 is a polyanionic carbosilane dendrimer capable of inhibiting HIV-1 in vitro and in vivo by interacting directly with viral particles. One of the main barriers for HIV-1 eradication is the reservoirs created in primoinfection. These reservoirs, mainly in T cells, are untargetable by actual drugs or immune system. Thus, one approach is inhibiting HIV-1 from reaching these reservoir cells. In this context, macrophages play a main role as they can deliver viral particles to T cells establishing reservoirs. We showed that G2-S16 dendrimer is capable of inhibiting the infection from infected macrophages to healthy T CD4/CD8 lymphocytes by eliminating HIV-1 infectivity inside macrophages, so they are not able to carry infectious particles to other body locations, thus preventing the reservoirs from forming.


Assuntos
Alcanossulfonatos/farmacologia , Fármacos Anti-HIV/farmacologia , Dendrímeros/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Compostos de Organossilício/farmacologia , Silanos/farmacologia , Linhagem Celular , Células Cultivadas , Infecções por HIV/transmissão , Humanos , Macrófagos/virologia , Polieletrólitos/farmacologia
4.
Acc Chem Res ; 54(17): 3349-3361, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34403258

RESUMO

Treatment of HIV-1 has largely involved targeting viral enzymes using a cocktail of inhibitors. However, resistance to these inhibitors and toxicity in the long term have pushed the field to identify new therapeutic targets. To that end, -1 programmed ribosomal frameshifting (-1 PRF) has gained attention as a potential node for therapeutic intervention. In this process, a ribosome moves one nucleotide backward in the course of translating a mRNA, revealing a new reading frame for protein synthesis. In HIV-1, -1 PRF allows the virus to regulate the ratios of enzymatic and structural proteins as needed for correct viral particle assembly. Two RNA structural elements are central to -1 PRF in HIV: a slippery sequence and a highly conserved stable hairpin called the HIV-1 frameshifting stimulatory signal (FSS). Dysregulation of -1 PRF is deleterious for the virus. Thus, -1 PRF is an attractive target for new antiviral development. It is important to note that HIV-1 is not the only virus exploiting -1 PRF for regulating production of its proteins. Coronaviruses, including the COVID-19 pandemic virus SARS-CoV-2, also rely on -1 PRF. In SARS-CoV-2 and other coronaviruses, -1 PRF is required for synthesis of RNA-dependent RNA polymerase and several other nonstructural proteins. Coronaviruses employ a more complex RNA structural element for regulating -1 PRF called a pseudoknot. The purpose of this Account is primarily to review the development of molecules targeting HIV-1 -1 PRF. These approaches are case studies illustrating how the entire pipeline from screening to the generation of high-affinity leads might be implemented. We consider both target-based and function-based screening, with a particular focus on our group's approach beginning with a resin-bound dynamic combinatorial library (RBDCL) screen. We then used rational design approaches to optimize binding affinity, selectivity, and cellular bioavailability. Our tactic is, to the best of our knowledge, the only study resulting in compounds that bind specifically to the HIV-1 FSS RNA and reduce infectivity of laboratory and drug-resistant strains of HIV-1 in human cells. Lessons learned from strategies targeting -1 PRF HIV-1 might provide solutions in the development of antivirals in areas of unmet medical need. This includes the development of new frameshift-altering therapies for SARS-CoV-2, approaches to which are very recently beginning to appear.


Assuntos
Antivirais/farmacologia , HIV-1/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Antivirais/química , Técnicas de Química Combinatória , Mudança da Fase de Leitura do Gene Ribossômico/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
5.
Viruses ; 13(6)2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208165

RESUMO

Affordable, sensitive, and scalable technologies are needed for monitoring antiretroviral treatment (ART) success with the goal of eradicating HIV-1 infection. This review discusses use of Sanger sequencing and next generation sequencing (NGS) methods for HIV-1 drug resistance (HIVDR) genotyping, focusing on their use in resource limited settings (RLS). Sanger sequencing remains the gold-standard method for detecting HIVDR mutations of clinical relevance but is mainly limited by high sequencing costs and low-throughput. NGS is becoming a more common sequencing method, with the ability to detect low-abundance drug-resistant variants and reduce per sample costs through sample pooling and massive parallel sequencing. However, use of NGS in RLS is mainly limited by infrastructure costs. Given these shortcomings, our review discusses sequencing technologies for HIVDR genotyping, focusing on common in-house and commercial assays, challenges with Sanger sequencing in keeping up with changes in HIV-1 treatment programs, as well as challenges with NGS that limit its implementation in RLS and in clinical diagnostics. We further discuss knowledge gaps and offer recommendations on how to overcome existing barriers for implementing HIVDR genotyping in RLS, to make informed clinical decisions that improve quality of life for people living with HIV.


Assuntos
Farmacorresistência Viral , Genótipo , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Técnicas de Genotipagem , Infecções por HIV/tratamento farmacológico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação
6.
Molecules ; 26(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206893

RESUMO

PF74 is a capsid-targeting inhibitor of HIV replication that effectively perturbs the highly sensitive viral uncoating process. A lack of information regarding the optical purity (enantiomeric excess) of the single stereogenic centre of PF74 has resulted in ambiguity as to the potency of different samples of this compound. Herein is described the synthesis of enantiomerically enriched (S)- and (R)-PF74 and further enrichment of the samples (≥98%) using chiral HPLC resolution. The biological activities of each enantiomer were then evaluated, which determined (S)-PF74 (IC50 1.5 µM) to be significantly more active than (R)-PF74 (IC50 19 µM). Computational docking studies were then conducted to rationalise this large discrepancy in activity, which indicated different binding conformations for each enantiomer. The binding energy of the conformation adopted by the more active (S)-PF74 (ΔG = -73.8 kcal/mol) was calculated to be more favourable than the conformation adopted by the less active (R)-enantiomer (ΔG = -55.8 kcal/mol) in agreement with experimental observations.


Assuntos
Fármacos Anti-HIV/farmacologia , Proteínas do Capsídeo/metabolismo , Capsídeo/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Indóis/farmacologia , Fenilalanina/análogos & derivados , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Capsídeo/química , Cromatografia Líquida de Alta Pressão , Células HEK293 , Humanos , Indóis/síntese química , Indóis/química , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Fenilalanina/síntese química , Fenilalanina/química , Fenilalanina/farmacologia , Estereoisomerismo
7.
Molecules ; 26(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200973

RESUMO

Nucleocapsid proteins (NCp) are zinc finger (ZF) proteins, and they play a central role in HIV virus replication, mainly by interacting with nucleic acids. Therefore, they are potential targets for anti-HIV therapy. Natural products have been shown to be able to inhibit HIV, such as turmeric and licorice, which is widely used in traditional Chinese medicine. Liquiritin (LQ), isoliquiritin (ILQ), glycyrrhizic acid (GL), glycyrrhetinic acid (GA) and curcumin (CUR), which were the major active components, were herein chosen to study their interactions with HIV-NCp7 C-terminal zinc finger, aiming to find the potential active compounds and reveal the mechanism involved. The stacking interaction between NCp7 tryptophan and natural compounds was evaluated by fluorescence. To elucidate the binding mode, mass spectrometry was used to characterize the reaction mixture between zinc finger proteins and active compounds. Subsequently, circular dichroism (CD) spectroscopy and molecular docking were used to validate and reveal the binding mode from a structural perspective. The results showed that ILQ has the strongest binding ability among the tested compounds, followed by curcumin, and the interaction between ILQ and the NCp7 zinc finger peptide was mediated by a noncovalent interaction. This study provided a scientific basis for the antiviral activity of turmeric and licorice.


Assuntos
Fármacos Anti-HIV/farmacologia , Produtos Biológicos/farmacologia , Curcuma/química , Glycyrrhiza/química , HIV-1/efeitos dos fármacos , Dedos de Zinco/efeitos dos fármacos , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Produtos Biológicos/química , Proteínas do Capsídeo/metabolismo , HIV-1/metabolismo , Proteínas do Nucleocapsídeo/metabolismo , Replicação Viral/efeitos dos fármacos
8.
Arch Virol ; 166(9): 2451-2460, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34195923

RESUMO

Human immunodeficiency virus (HIV) with transmitted drug-resistance (TDR) limits the therapeutic options available for treatment-naive HIV patients. This study aimed to further our understanding of the prevalence and transmission characteristics of HIV with TDR for the application of first-line antiretroviral regimens. A total of 6578 HIV-1 protease/reverse-transcriptase sequences from treatment-naive individuals in China between 2000 and 2016 were obtained from the Los Alamos HIV Sequence Database and were analyzed for TDR. Transmission networks were constructed to determine genetic relationships. The spreading routes of large TDR clusters were identified using a Bayesian phylogeographic framework. TDR mutations were detected in 274 (4.51%) individuals, with 1.40% associated with resistance to nucleoside reverse transcriptase inhibitors, 1.52% to non-nucleoside reverse transcriptase inhibitors, and 1.87% to protease inhibitors. The most frequent mutation was M46L (58, 0.89%), followed by K103N (36, 0.55%), M46I (36, 0.55%), and M184V (26, 0.40%). The prevalence of total TDR initially decreased between 2000 and 2010 (OR = 0.83, 95% CI 0.73-0.95) and then increased thereafter (OR = 1.50, 95% CI 1.13-1.97). The proportion of sequences in a cluster (clustering rate) among HIV isolates with TDR sequences was lower than that of sequences without TDR (40.5% vs. 48.8%, P = 0.023) and increased from 27.3% in 2005-2006 to 63.6% in 2015-2016 (P < 0.001). While most TDR mutations were associated with reduced relative transmission fitness, mutation M46I was associated with higher relative transmission fitness than the wild-type strain. This study identified a low-level prevalence of TDR HIV in China during the last two decades. However, the increasing TDR HIV rate since 2010, the persistent circulation of drug resistance mutations, and the expansion of self-sustaining drug resistance reservoirs may compromise the efficacy of antiretroviral therapy programs.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , Prevalência , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , China/epidemiologia , Farmacorresistência Viral/genética , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Masculino , Mutação , Filogenia
9.
Lancet HIV ; 8(7): e397-e407, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34197772

RESUMO

BACKGROUND: In DISCOVER, a multinational, randomised controlled trial, emtricitabine and tenofovir alafenamide compared with emtricitabine and tenofovir disoproxil fumarate showed non-inferior efficacy for HIV prevention and improved bone mineral density and renal safety biomarkers at week 48. We report outcomes analysed after all participants had completed 96 weeks of follow-up. METHODS: This study is an ongoing, randomised, double-blind, multicentre, active-controlled, phase 3, non-inferiority trial done at 94 community, public health, and hospital-associated clinics located in Europe and North America. Adult cisgender men and transgender women who have sex with men, both with a high risk of acquiring HIV as determined by self-reported sexual behaviour or recent sexually transmitted infections, were randomly assigned (1:1) to receive either emtricitabine and tenofovir alafenamide (200/25 mg) tablets daily, with matched placebo tablets (emtricitabine and tenofovir alafenamide group), or emtricitabine and tenofovir disoproxil fumarate (200/300 mg) tablets daily, with matched placebo tablets (emtricitabine and tenofovir disoproxil fumarate group). The primary efficacy outcome was incident HIV infection. Incidence of HIV-1 infection per 100 person-years was assessed when the last participant had completed 96 weeks of follow-up. This trial is registered with ClinicalTrials.gov, number NCT02842086. FINDINGS: Between Sept 13, 2016, and June 30, 2017, 5387 participants were randomly assigned to receive emtricitabine and tenofovir alafenamide (n=2694) or emtricitabine and tenofovir disoproxil fumarate (n=2693), contributing 10 081 person-years of follow-up. At 96 weeks of follow-up, there were eight HIV infections in participants who had received emtricitabine and tenofovir alafenamide (0·16 infections per 100 person-years [95% CI 0·07-0·31]) and 15 in participants who had received emtricitabine and tenofovir disoproxil fumarate (0·30 infections per 100 person-years [0·17-0·49]). Emtricitabine and tenofovir alafenamide maintained its non-inferiority to emtricitabine and tenofovir disoproxil fumarate for HIV prevention (IRR 0·54 [95% CI 0·23-1·26]). Approximately 78-82% of participants reported taking study medication more than 95% of the time across all study visits. Rates of sexually transmitted infections remained high and similar across groups (21 cases per 100 person-years for rectal gonorrhoea and 28 cases per 100 person-years for rectal chlamydia). Emtricitabine and tenofovir alafenamide continued to show superiority over emtricitabine and tenofovir disoproxil fumarate in all but one of the six prespecified bone mineral density and renal biomarkers. There was more weight gain among participants who had received emtricitabine and tenofovir alafenamide (median weight gain 1·7 kg vs 0·5 kg, p<0·0001). INTERPRETATION: Emtricitabine and tenofovir alafenamide is safe and effective for longer-term pre-exposure prophylaxis in cisgender men and transgender women who have sex with men. FUNDING: Gilead Sciences.


Assuntos
Adenina/análogos & derivados , Alanina/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Emtricitabina/uso terapêutico , Infecções por HIV/prevenção & controle , Organofosfonatos/uso terapêutico , Tenofovir/uso terapêutico , Adenina/efeitos adversos , Adenina/uso terapêutico , Adulto , Idoso , Alanina/efeitos adversos , Fármacos Anti-HIV/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Emtricitabina/efeitos adversos , Feminino , Seguimentos , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Organofosfonatos/efeitos adversos , Profilaxia Pré-Exposição , Tenofovir/efeitos adversos , Resultado do Tratamento , Adulto Jovem
10.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199858

RESUMO

The approval of the first HIV-1 protease inhibitors (HIV-1 PRIs) marked a fundamental step in the control of AIDS, and this class of agents still represents the mainstay therapy for this illness. Despite the undisputed benefits, the necessary lifelong treatment led to numerous severe side-effects (metabolic syndrome, hepatotoxicity, diabetes, etc.). The HIV-1 PRIs are capable of interacting with "secondary" targets (off-targets) characterized by different biological activities from that of HIV-1 protease. In this scenario, the in-silico techniques undoubtedly contributed to the design of new small molecules with well-fitting selectivity against the main target, analyzing possible undesirable interactions that are already in the early stages of the research process. The present work is focused on a new mixed-hierarchical, ligand-structure-based protocol, which is centered on an on/off-target approach, to identify the new selective inhibitors of HIV-1 PR. The use of the well-established, ligand-based tools available in the DRUDIT web platform, in combination with a conventional, structure-based molecular docking process, permitted to fast screen a large database of active molecules and to select a set of structure with optimal on/off-target profiles. Therefore, the method exposed herein, could represent a reliable help in the research of new selective targeted small molecules, permitting to design new agents without undesirable interactions.


Assuntos
Desenho de Fármacos , Descoberta de Drogas , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Protease de HIV/química , HIV-1/efeitos dos fármacos , Domínio Catalítico , Simulação por Computador , Infecções por HIV/enzimologia , Infecções por HIV/virologia , HIV-1/enzimologia , Humanos , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Conformação Proteica , Relação Estrutura-Atividade
11.
BMC Infect Dis ; 21(1): 668, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34243716

RESUMO

BACKGROUND: To assess transmitted drug resistance (TDR) to tenofovir (TDF)/emtricitabine (FTC), using as pre-exposure prophylaxis, among newly diagnosed human immunodeficiency virus-1 (HIV-1)-infected residents in Shenyang city, northeast China. METHODS: Demographic and epidemiological information of all newly diagnosed HIV-1 infected residents in Shenyang city from 2016 to 2018 were anonymously collected from the local HIV epidemic database. HIV-1 pol sequences were amplified from RNA in cryopreserved plasma samples and sequenced directly. Viral subtypes were inferred with phylogenetic analysis and drug resistance mutations (DRMs) were determined according to the Stanford HIVdb algorithm. Recent HIV infection was determined with HIV Limiting Antigen avidity electro immunoassay. RESULTS: A total of 2176 sequences (92.4%, 2176/2354) were obtained; 70.9% (1536/2167) were CRF01_AE, followed by CRF07_BC (18.0%, 391/2167), subtype B (4.7%, 102/2167), other subtypes (2.6%, 56/2167), and unique recombinant forms (3.8%, 82/2167). The prevalence of TDR was 4.9% (107/2167), among which, only 0.6% (13/2167) was resistance to TDF/FTC. Most of these subjects had CRF01_AE strains (76.9%, 10/13), were unmarried (76.9%, 10/13), infected through homosexual contact (92.3%, 12/13), and over 30 years old (median age: 33). The TDF/FTC DRMs included K65R (8/13), M184I/V (5/13), and Y115F (2/13). Recent HIV infection accounted for only 23.1% (3/13). Most cases were sporadic in the phylogenetic tree, except two CRF01_AE sequences with K65R (Bootstrap value: 99%). CONCLUSIONS: The prevalence of TDR to TDF/FTC is low among newly diagnosed HIV-infected cases in Shenyang, suggesting that TDR may have little impact on the protective effect of the ongoing CROPrEP project in Shenyang city.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Emtricitabina/uso terapêutico , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Tenofovir/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Farmacorresistência Viral/genética , Epidemias , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto Jovem
12.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207212

RESUMO

Long-acting (LA) HIV pre-exposure prophylaxis (PrEP) can mitigate challenges of adhering to daily or on-demand regimens of antiretrovirals (ARVs). We are developing a subcutaneous implant comprising polycaprolactone (PCL) for sustained delivery of ARVs for PrEP. Here we use tenofovir alafenamide (TAF) as a model drug. Previously, we demonstrated that the release rates of drugs are controlled by the implant surface area and wall thickness, and the molecular weight (MW) of PCL. Here, we further advance the implant design and tailor the release rates of TAF and the mechanical integrity of the implant through unique polymer blend formulations. In vitro release of TAF from the implant exhibited zero-order release kinetics for ~120 days. TAF release rates were readily controlled via the MW of the polymer blend, with PCL formulations of higher MW releasing the drug faster than implants with lower MW PCL. Use of polymer MW to tune drug release rates is partly explained by PCL crystallinity, as higher PCL crystalline material is often associated with a slower release rate. Moreover, results showed the ability to tailor mechanical properties via PCL blends. Blending PCL offers an effective approach for tuning the ARV release rates, implant duration, and integrity, and ultimately the biodegradation profiles of the implant.


Assuntos
Implantes Absorvíveis , Fármacos Anti-HIV/administração & dosagem , Materiais Biocompatíveis , Preparações de Ação Retardada , Polímeros , Profilaxia Pré-Exposição/métodos , Materiais Biocompatíveis/química , Fenômenos Químicos , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Polímeros/química , Difração de Raios X
13.
AAPS PharmSciTech ; 22(5): 171, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34100170

RESUMO

Macrophages act as a cellular reservoir in HIV infection. Elimination of HIV from macrophages has been an unfulfilled dream due to the failure of drugs to reach them. To address this, we developed CD44 receptor-targeted, novel hyaluronic acid (HA)-coated nanostructured lipid carriers (NLCs) of efavirenz via washless layer-by-layer (LbL) assembly of HA and polyallylamine hydrochloride (PAH). NLCs were subjected to TEM analysis, size and zeta potential, in vitro release and encapsulation efficiency studies. The uptake of NLCs in THP-1 cells was studied using fluorescence microscopy and flow cytometry. The anti-HIV efficacy was evaluated using p24 antigen inhibition assay. NLCs were found to be spherical in shape with anionic zeta potential (-23.66 ± 0.87 mV) and 241.83 ± 5.38 nm particle size. NLCs exhibited prolonged release of efavirenz during in vitro drug release studies. Flow cytometry revealed 1.73-fold higher uptake of HA-coated NLCs in THP-1 cells. Cytotoxicity studies showed no significant change in cell viability in presence of NLCs as compared with the control. HA-coated NLCs distributed throughout the cell including cytoplasm, plasma membrane and nucleus, as observed during fluorescence microscopy. HA-coated NLCs demonstrated consistent and significantly higher inhibition (81.26 ± 1.70%) of p24 antigen which was 2.08-fold higher than plain NLCs. The obtained results suggested preferential uptake of HA-coated NLCs via CD44-mediated uptake. The present finding demonstrates that HA-based CD44 receptor targeting in HIV infection is an attractive strategy for maximising the drug delivery to macrophages and achieve effective viral inhibition.


Assuntos
Portadores de Fármacos/administração & dosagem , HIV-1/efeitos dos fármacos , Receptores de Hialuronatos , Macrófagos/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Inibidores da Transcriptase Reversa/administração & dosagem , Alcinos/administração & dosagem , Alcinos/síntese química , Alcinos/metabolismo , Benzoxazinas/administração & dosagem , Benzoxazinas/síntese química , Benzoxazinas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Ciclopropanos/administração & dosagem , Ciclopropanos/síntese química , Ciclopropanos/metabolismo , Relação Dose-Resposta a Droga , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Células HEK293 , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , HIV-1/fisiologia , Humanos , Receptores de Hialuronatos/metabolismo , Lipídeos/administração & dosagem , Lipídeos/síntese química , Macrófagos/metabolismo , Nanoestruturas/química , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/metabolismo , Células THP-1
14.
Int J Mol Sci ; 22(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068829

RESUMO

Cassia abbreviata is widely used in Sub-Saharan Africa for treating many diseases, including HIV-1 infection. We have recently described the chemical structures of 28 compounds isolated from an alcoholic crude extract of barks and roots of C. abbreviata, and showed that six bioactive compounds inhibit HIV-1 infection. In the present study, we demonstrate that the six compounds block HIV-1 entry into cells: oleanolic acid, palmitic acid, taxifolin, piceatannol, guibourtinidol-(4α→8)-epiafzelechin, and a novel compound named as cassiabrevone. We report, for the first time, that guibourtinidol-(4α→8)-epiafzelechin and cassiabrevone inhibit HIV-1 entry (IC50 of 42.47 µM and 30.96 µM, respectively), as well as that piceatannol interacts with cellular membranes. Piceatannol inhibits HIV-1 infection in a dual-chamber assay mimicking the female genital tract, as well as HSV infection, emphasizing its potential as a microbicide. Structure-activity relationships (SAR) showed that pharmacophoric groups of piceatannol are strictly required to inhibit HIV-1 entry. By a ligand-based in silico study, we speculated that piceatannol and norartocarpetin may have a very similar mechanism of action and efficacy because of the highly comparable pharmacophoric and 3D space, while guibourtinidol-(4α→8)-epiafzelechin and cassiabrevone may display a different mechanism. We finally show that cassiabrevone plays a major role of the crude extract of CA by blocking the binding activity of HIV-1 gp120 and CD4.


Assuntos
Cassia/química , Infecções por HIV/tratamento farmacológico , Extratos Vegetais/farmacologia , Internalização do Vírus/efeitos dos fármacos , Catequina/farmacologia , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Ácido Oleanólico/farmacologia , Ácido Palmítico/farmacologia , Extratos Vegetais/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/virologia , Quercetina/análogos & derivados , Quercetina/farmacologia , Estilbenos/farmacologia
15.
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
16.
Front Immunol ; 12: 639378, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093527

RESUMO

Microglia, the resident brain phagocytes, likely play a key role in human immunodeficiency virus (HIV) infection of the central nervous system (CNS) and subsequent neuropathogenesis; however, the nature of the infection-induced changes that yield damaging CNS effects and the stimuli that provoke microglial activation remains elusive, especially in the current era of using antiretroviral (ARV) drugs for ARV therapy (ART). Altered microglial metabolism can modulate cellular functionality and pathogenicity in neurological disease. While HIV infection itself alters brain energy metabolism, the effect of ARV drugs, particularly those currently used in treatment, on metabolism is understudied. Dolutegravir (DTG) and emtricitabine (FTC) combination, together with tenofovir (TAF or TDF), is one of the recommended first line treatments for HIV. Despite the relatively good tolerability and safety profile of FTC, a nucleoside reverse transcriptase inhibitor, and DTG, an integrase inhibitor, adverse side effects have been reported and highlight a need to understand off-target effects of these medications. We hypothesized that similar to previous ART regimen drugs, DTG and FTC side effects involve mitochondrial dysfunction. To increase detection of ARV-induced mitochondrial effects, highly glycolytic HeLa epithelial cells were forced to rely on oxidative phosphorylation by substituting galactose for glucose in the growth media. We assessed ATP levels, resazurin oxidation-reduction (REDOX), and mitochondrial membrane potential following 24-hour exposure (to approximate effects of one dose equivalent) to DTG, FTC, and efavirenz (EFV, a known mitotoxic ARV drug). Further, since microglia support productive HIV infection, act as latent HIV cellular reservoirs, and when dysfunctional likely contribute to HIV-associated neurocognitive disorders, the experiments were repeated using BV2 microglial cells. In HeLa cells, FTC decreased mitochondrial REDOX activity, while DTG, similar to EFV, impaired both mitochondrial ATP generation and REDOX activity. In contrast to HeLa cells, DTG increased cellular ATP generation and mitochondrial REDOX activity in BV2 cells. Bioenergetic analysis revealed that DTG, FTC, and EFV elevated BV2 cell mitochondrial respiration. DTG and FTC exposure induced distinct mitochondrial functional changes in HeLa and BV2 cells. These findings suggest cell type-specific metabolic changes may contribute to the toxic side effects of these ARV drugs.


Assuntos
Alcinos/farmacologia , Fármacos Anti-HIV/farmacologia , Benzoxazinas/farmacologia , Ciclopropanos/farmacologia , Emtricitabina/farmacologia , Células Epiteliais/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/farmacologia , Microglia/efeitos dos fármacos , Oxazinas/farmacologia , Piperazinas/farmacologia , Piridonas/farmacologia , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microglia/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxazinas/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Latência Viral/efeitos dos fármacos , Xantenos/metabolismo
18.
Viruses ; 13(5)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064894

RESUMO

The year 2021 marks the 40th anniversary since physicians recognized symptoms of the acquired immunodeficiency syndrome (AIDS), a disease that has since caused more than 30 million deaths worldwide. Despite the passing of four decades, there remains no licensed vaccine for the human immunodeficiency virus type 1 (HIV-1), the etiologic agent of AIDS. Despite the development of outstanding anti-retroviral drugs, there are currently more than one-half million deaths each year due to AIDS. Here, we revisit a conventional vaccine strategy used for protection against variable pathogens like HIV-1, which combines an array of diverse surface antigens. The strategy uses antibody recognition patterns to categorize viruses and their surface antigens into groups. Then a leader is assigned for each group and group leaders are formulated into vaccine cocktails. The group leaders are 'natural mosaics', because they share one or more epitope(s) with each of the other group members. We encourage the application of this conventional approach to HIV-1 vaccine design. We suggest that the partnering of an antibody-instructed envelope cocktail with new vaccine vectors will yield a successful vaccine in the HIV-1 field.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , Animais , Desenho de Fármacos , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , Humanos
19.
Viruses ; 13(5)2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066522

RESUMO

Viral entry into host cells is a critical step in the viral life cycle. HIV-1 entry is mediated by the sole surface envelope glycoprotein Env and is initiated by the interaction between Env and the host receptor CD4. This interaction, referred to as the attachment step, has long been considered an attractive target for inhibitor discovery and development. Fostemsavir, recently approved by the FDA, represents the first-in-class drug in the attachment inhibitor class. This review focuses on the discovery of temsavir (the active compound of fostemsavir) and analogs, mechanistic studies that elucidated the mode of action, and structural studies that revealed atomic details of the interaction between HIV-1 Env and attachment inhibitors. Challenges associated with emerging resistance mutations to the attachment inhibitors and the development of next-generation attachment inhibitors are also highlighted.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Organofosfatos/farmacologia , Piperazinas/farmacologia , Animais , Fármacos Anti-HIV/química , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Organofosfatos/química , Piperazinas/química , Internalização do Vírus/efeitos dos fármacos
20.
Nat Commun ; 12(1): 2475, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931637

RESUMO

An innovative approach to eliminate HIV-1-infected cells emerging out of latency, the major hurdle to HIV-1 cure, is to pharmacologically reactivate viral expression and concomitantly trigger intracellular pro-apoptotic pathways in order to selectively induce cell death (ICD) of infected cells, without reliance on the extracellular immune system. In this work, we demonstrate the effect of DDX3 inhibitors on selectively inducing cell death in latent HIV-1-infected cell lines, primary CD4+ T cells and in CD4+ T cells from cART-suppressed people living with HIV-1 (PLWHIV). We used single-cell FISH-Flow technology to characterise the contribution of viral RNA to inducing cell death. The pharmacological targeting of DDX3 induced HIV-1 RNA expression, resulting in phosphorylation of IRF3 and upregulation of IFNß. DDX3 inhibition also resulted in the downregulation of BIRC5, critical to cell survival during HIV-1 infection, and selectively induced apoptosis in viral RNA-expressing CD4+ T cells but not bystander cells. DDX3 inhibitor treatment of CD4+ T cells from PLWHIV resulted in an approximately 50% reduction of the inducible latent HIV-1 reservoir by quantitation of HIV-1 RNA, by FISH-Flow, RT-qPCR and TILDA. This study provides proof of concept for pharmacological reversal of latency coupled to induction of apoptosis towards the elimination of the inducible reservoir.


Assuntos
Apoptose/efeitos dos fármacos , Azepinas/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , RNA Helicases DEAD-box/metabolismo , Infecções por HIV/imunologia , HIV-1/metabolismo , Imidazóis/farmacologia , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Antirretrovirais/farmacologia , Apoptose/genética , Azepinas/química , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , RNA Helicases DEAD-box/antagonistas & inibidores , RNA Helicases DEAD-box/química , Inibidores Enzimáticos/farmacologia , Infecções por HIV/genética , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Imidazóis/química , Hibridização in Situ Fluorescente , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/metabolismo , Células Jurkat , Simulação de Acoplamento Molecular , RNA Viral/metabolismo , Análise de Célula Única , Survivina/metabolismo , Ativação Viral/efeitos dos fármacos , Replicação Viral/genética
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