RESUMO
BACKGROUND: This study presents the synthesis and multi-target behavior of the new 5'-hydroxy-3-(chalcogenyl-triazoyl)-thymidine and the biological evaluation of these compounds as antioxidant and anti-HIV agents. OBJECTIVE: Antiretroviral therapy induces oxidative stress. Based on this, this manuscript's main objective is to prepare compounds that combine anti-HIV and antioxidant activities. METHODS: The compounds were prepared from commercially available AZT through a copper-catalyzed Huisgen 1,3-dipolar cycloaddition exploiting the AZT azide group and chalcogenyl alkynes. RESULTS: The chalcogenium-AZT derivatives were obtained in good yields via click chemistry. The compounds evaluated showed antioxidant and anti-HIV activity. Additionally, in vivo toxicity of this class of compounds was also evaluated. The representative nucleoside did not change the survival, behavior, biochemical hepatic, or renal markers compared to the control mice. CONCLUSION: Data suggest the feasibility of modifying the AZT nucleus with simple organohalogen fragments, exploring the reactivity of the azide group via 1,3-dipolar Huisgen cycloaddition reaction. The design of these new compounds showed the initially desired biological activities.
Assuntos
Fármacos Anti-HIV , Infecções por HIV , Animais , Camundongos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Azidas/química , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/química , Infecções por HIV/tratamento farmacológico , Estresse Oxidativo , Zidovudina/farmacologia , Zidovudina/metabolismoRESUMO
The concept of polypharmacology embraces multiple drugs combined in a therapeutic regimen (drug combination or cocktail), fixed dose combinations (FDCs), and a single drug that binds to different targets (multi-target drug). A polypharmacology approach is widely applied in the treatment of acquired immunodeficiency syndrome (AIDS), providing life-saving therapies for millions of people living with HIV. Despite the success in viral load suppression and patient survival of combined antiretroviral therapy (cART), the development of new drugs has become imperative, owing to the emergence of resistant strains and poor adherence to cART. 3'-azido-2',3'-dideoxythymidine, also known as azidothymidine or zidovudine (AZT), is a widely applied starting scaffold in the search for new compounds, due to its good antiretroviral activity. Through the medicinal chemistry tool of molecular hybridization, AZT has been included in the structure of several compounds allowing for the development of multi-target-directed ligands (MTDLs) as antiretrovirals. This review aims to systematically explore and critically discuss AZT-based compounds as potential MTDLs for the treatment of AIDS. The review findings allowed us to conclude that: (i) AZT hybrids are still worth exploring, as they may provide highly active compounds targeting different steps of the HIV-1 replication cycle; (ii) AZT is a good starting point for the preparation of co-drugs with enhanced cell permeability.
Assuntos
Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , HIV-1 , Humanos , Zidovudina/farmacologia , Zidovudina/uso terapêutico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Farmacóforo , Carga Viral , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêuticoRESUMO
A reversed-phase high performance liquid chromatography (RP-HPLC) method with ultraviolet detection was developed and validated for the simultaneous quantification of antiretroviral drugs lamivudine (3TC), stavudine (d4T), and zidovudine (AZT) in perfusate samples obtained from the Single-Pass Intestinal Perfusion studies. The chromatographic analysis was performed using a Gemini C18 column and didanosine as internal standard (IS). The following parameters were considered for the validation procedure: system suitability, accuracy, precision, linearity and selectivity. The limits of detection were 0.32 µg/mL for 3TC, 0.11 µg/mL for d4T and 0.45 µg/mL for AZT and the limits of quantification were 1.06 µg/mL for 3TC, 0.38 µg/mL for d4T and 1.51 µg/mL for AZT. Repeatability and intermediate precision ranged from 1.05 to 1.31 and 1.50 to 1.87, respectively, and are expressed as percent of relative standard deviation (RSD). Based on these results, the developed and validated RP-HPLC method can be used for simultaneous determination of 3TC, d4T, and AZT in perfusate samples. Furthermore, this method is simple and adequate for measurements of the antiretroviral drugs in the same sample, since those compounds are mostly co-administered. Besides, this work can be used as an initial base for the development of similar methods in the same conditions presented in our study.
Assuntos
Zidovudina/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Lamivudina/farmacologia , Estudo de Validação , Antirretrovirais/farmacologia , Perfusão/instrumentação , Permeabilidade , Preparações Farmacêuticas/administração & dosagem , Limite de DetecçãoRESUMO
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/farmacologiaRESUMO
The present study aimed to investigate the effect of AZT derivates containing tellurium (Te) on human breast cancer cell lines and the mechanisms underlying cell death. The inhibitory effect of AZT and its derivatives (7m and 7r) was determined by the MTT assay (6.25, 12.5, 25, 50 and 100 µM in 24 and 48 h time points), meanwhile the induction of apoptosis and the cell cycle phases was investigated by flow cytometry. The MTT assay showed that AZT derivatives decreased the rate of cell proliferation at concentrations of 12.5 µM, while commercial AZT showed low antitumor potential. In flow cytometric analysis, we demonstrate that the AZT derivatives do not induce apoptosis at the concentration tested and promote the cell cycle arrest in the S phase. Besides, predicted absorption, distribution, metabolization, excretion and toxicity analysis suggest that the compounds possess a good pharmacokinetic profile and possibly less toxicity when compared to conventional AZT. These compounds containing tellurium in their formulation are potential therapeutic agents for breast cancer.
Assuntos
Antineoplásicos/síntese química , Zidovudina/análogos & derivados , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Meia-Vida , Humanos , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Telúrio/química , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Zidovudina/síntese química , Zidovudina/farmacocinética , Zidovudina/farmacologiaRESUMO
BACKGROUND: The strategic development of therapeutic agents, capable of being targeted at their active sites, has been a major goal in treatment of cancer. The delivery of drugs for tumors has as its main challenge the development of safe and effective drugs, since the goal of chemotherapy is to eliminate the tumor completely without affecting healthy cells. The aim of present study was to investigate the antioxidant, anticancer activities of zidovudine and its α-O-glycosylated derivative obtained by biosynthesis of a filamentous fungi, Cunninghamela echinulata. METHODS: An evaluation of the cytotoxic potential of zidovudine and its α-O-glycosylated was performed in fibroblasts and melanoma cells by the tetrazolium reduction method (MTT) and the antioxidant activity of this derivative was observed. RESULTS: The antioxidant activity of zidovudine demonstrated an electrochemical oxidation potential of 0.91V, while the α-O-glycosylated derivative did not exhibit any antioxidant activity. The zidovudine exhibited low cytotoxicity for melanoma and fibroblast cells, while the α-O-glycosylated derivative presented better cytotoxicity on melanoma cells at a concentration of 10mg. mL-1. CONCLUSION: This study demonstrates the specific cytotoxicity of the glycoconjugate and suggests that glycosylation by biosynthesis can be a useful strategy for obtaining new anticancer compounds.
Assuntos
Antineoplásicos/farmacologia , Cunninghamella/metabolismo , Zidovudina/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glicosilação , Camundongos , Estrutura Molecular , Oxirredução , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Zidovudina/química , Zidovudina/metabolismoRESUMO
BACKGROUND: The development of antiretroviral associations in a single dosage form aims to ensure improved efficacy, low costs and better adherence to treatment. OBJECTIVE: This work performed the pharmacotechnical development, coating, and stability studies of fixed-dose combination tablets of zidovudine, lamivudine and nevirapine (300 + 200 + 150 mg, respectively). METHODS: Qualitative and quantitative planning of diluents (101 and 250 microcrystalline cellulose, spray-dried monohydrate lactose and corn starch) and coating polymers (Opadry white II HP® and Instacoat Aqua Moistshield II®) were analyzed, and direct compression (DC) and wet granulation (WG) methods were tested aiming the development of the pharmaceutical form. Quality control was carried out according to the specifications set by official compendia. The chosen formulation was scaled-up and the industrial batches were submitted to accelerated and long-term stability studies. RESULTS: The batches obtained by WG met the requirements, using 101 microcrystalline cellulose, corn starch and Opadry white II HP® as excipients. The DC trial was not possible due to the need of a greater ratio of excipients to improve formulation properties. CONCLUSION: Thus, this study brings a new therapeutic alternative for HIV treatment, contributing to the development of another possibility to simplify drug administration.
Assuntos
Fármacos Anti-HIV/farmacologia , Combinação de Medicamentos , Lamivudina/farmacologia , Nevirapina/farmacologia , Comprimidos , Zidovudina/farmacologia , Composição de Medicamentos , Desenvolvimento de Medicamentos , Estabilidade de Medicamentos , Tecnologia Farmacêutica/métodosRESUMO
Despite its vastly demonstrated clinical efficacy, zidovudine (AZT) exhibits several suboptimal pharmacokinetic properties. In particular, its short plasmatic half-life (t1/2â¯~â¯1â¯h) is related to its low bound fraction to whole plasmatic proteins and in particular to human serum albumin (HSA). The design of prodrugs constitutes a promising strategy to enhance AZT pharmacokinetic properties, including its affinity for HSA. Recently, we reported the synthesis and chemical stability evaluation of three novel prodrugs of AZT obtained by derivatization with dicarboxylic acids (1-3). In this work, we present the design, synthesis and evaluation of chemical and enzymatic stabilities of a novel series of double prodrugs of AZT obtained by derivatization of 1-3 with a methylated l-phenylalanine moiety (4-6). In addition, the plasmatic protein binding properties were studied both by experimental and theoretical techniques. Prodrugs 4-6 were found to be relatively stable at pHâ¯7.4 (t1/2 between 4.1 and 57.8â¯h), while also demonstrated adequate stabilities in human plasma at 37⯰C (t1/2 between 1.0 and 2.1â¯h). Also, prodrugs 4-6 were able to regenerate AZT at a rate that depended on the length of the alkyl chain in 1-3. Additionally, 4-6 exhibited a significantly increased binding to plasmatic proteins (between 52.1 and 72.5%) with respect to AZT (12%) and 1-3 (between 26 and 34%). It is noteworthy that the displacement experiments with HSA site I and II markers, demonstrated that 4-6 bound to a different site than that of AZT and 1-3. Molecular modeling studies (i.e. molecular docking and free energy of binding analysis) were applied to shed light at an atomistic level on the pharmacodynamic properties driving the interaction of 4-6 with HSA. Overall, the present work provides a state of the art contribution to the design and development of novel prodrugs of AZT with optimized pharmacokinetic properties.
Assuntos
Pró-Fármacos/química , Pró-Fármacos/farmacologia , Albumina Sérica Humana/metabolismo , Zidovudina/química , Zidovudina/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Proteínas Sanguíneas/metabolismo , Estabilidade de Medicamentos , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacosRESUMO
BACKGROUND & AIMS: Short telomeres and genetic telomerase defects are risk factors for some human liver diseases, ranging from non-alcoholic fatty liver disease and non-alcoholic steatohepatitis to cirrhosis. In murine models, telomere dysfunction has been shown to metabolically compromise hematopoietic cells, liver and heart via the activation of the p53-PGC axis. METHODS: Tert- and Terc-deficient mice were challenged with liquid high-fat diet. Liver metabolic contents were analysed by CE-TOFMS and liver fat content was confirmed by confocal and electronic microscopy. RESULTS: Tert-deficient but not Terc-deficient mice develop hepatocyte injury and frank steatosis when challenged with liquid high-fat diet. Upon high-fat diet, Tert-/- hepatocytes fail to engage the citric acid cycle (TCA), with an imbalance of NADPH/NADP+ and NADH/NAD+ ratios and depletion of intermediates of TCA cycle, such as cis-aconitic acid. Telomerase deficiency caused an intrinsic metabolic defect unresponsive to environmental challenge. Chemical inhibition of telomerase by zidovudine recapitulated the abnormal Tert-/- metabolic phenotype in Terc-/- hepatocytes. CONCLUSIONS: Our findings indicate that in telomeropathies short telomeres are not the only molecular trigger and telomerase enzyme deficiency provokes hepatocyte metabolic dysfunction, abrogates response to environmental challenge, and causes cellular injury and steatosis, providing a mechanism for liver damage in telomere diseases.
Assuntos
Dieta Hiperlipídica , Metabolismo Energético , Fígado Gorduroso/enzimologia , Hepatócitos/enzimologia , Metabolismo dos Lipídeos , Fígado/enzimologia , Telomerase/deficiência , Encurtamento do Telômero , Animais , Glicemia/metabolismo , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fígado Gorduroso/sangue , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA/genética , Telomerase/antagonistas & inibidores , Telomerase/genética , Zidovudina/farmacologiaRESUMO
Safety concerns for fetus development of zidovudine (AZT) administration as prophylaxis of vertical transmission of HIV persist. We evaluated the participation of the ATP-binding cassette efflux transporter ABCG2 in the penetration of AZT into the fetal brain and the relevance for drug safety. Oral daily doses of AZT (60mg/kg body weight) or its vehicle were administered between post gestational days 11 (E11) and 20 (E20) to Sprague-Dawley pregnant rats. At E21, animals received an intravenous bolus of 60mg AZT/kg body weight in the presence or absence of the ABCG2 inhibitor gefitinib (20mg/kg body weight, ip) and AZT in maternal plasma and fetal brain were measured by HPLC-UV. ABCG2 protein expression in placenta and fetal brain, as well as mitochondrial function and ultrastructure in fetal brain were also analyzed. In utero chronic exposure to AZT markedly induced ABCG2 expression in placenta and fetal brain whereas did not significantly alter mitochondrial functionality in the fetal brain. The area-under-the-concentration-time-curve of AZT significantly decreased in fetal brains isolated from AZT-exposed fetuses compared to control group, but this effect was abolished by ABCG2 inhibition. Our results suggest that the absence of mitochondrial toxicity in the fetal brain after chronic in utero administration of AZT could be attributed to its low accumulation in the tissue caused, at least in part, by ABCG2 overexpression. We propose that any interference with ABCG2 activity due to genetic, pathological or iatrogenic factors would increase the amount of AZT reaching the fetal brain, which could increase the risk of toxicity of this drug on the tissue.