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1.
Pharmacol Res Perspect ; 8(6): e00674, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33124786

RESUMO

SARS-CoV-2, a member of the coronavirus family, has caused a global public health emergency. Based on our analysis of hepatitis C virus and coronavirus replication, and the molecular structures and activities of viral inhibitors, we previously reasoned that the FDA-approved hepatitis C drug EPCLUSA (Sofosbuvir/Velpatasvir) should inhibit coronaviruses, including SARS-CoV-2. Here, using model polymerase extension experiments, we demonstrate that the active triphosphate form of Sofosbuvir is incorporated by low-fidelity polymerases and SARS-CoV RNA-dependent RNA polymerase (RdRp), and blocks further incorporation by these polymerases; the active triphosphate form of Sofosbuvir is not incorporated by a host-like high-fidelity DNA polymerase. Using the same molecular insight, we selected 3'-fluoro-3'-deoxythymidine triphosphate and 3'-azido-3'-deoxythymidine triphosphate, which are the active forms of two other anti-viral agents, Alovudine and AZT (an FDA-approved HIV/AIDS drug) for evaluation as inhibitors of SARS-CoV RdRp. We demonstrate the ability of two of these HIV reverse transcriptase inhibitors to be incorporated by SARS-CoV RdRp where they also terminate further polymerase extension. Given the 98% amino acid similarity of the SARS-CoV and SARS-CoV-2 RdRps, we expect these nucleotide analogues would also inhibit the SARS-CoV-2 polymerase. These results offer guidance to further modify these nucleotide analogues to generate more potent broad-spectrum anti-coronavirus agents.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , /antagonistas & inibidores , Betacoronavirus/enzimologia , Carbamatos/farmacologia , Infecções por Coronavirus/virologia , Didesoxinucleotídeos/farmacologia , Combinação de Medicamentos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Pandemias , Pneumonia Viral/virologia , Sofosbuvir/farmacologia , Nucleotídeos de Timina/farmacologia , Zidovudina/análogos & derivados , Zidovudina/farmacologia
2.
Anticancer Res ; 40(10): 5517-5527, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988875

RESUMO

BACKGROUND/AIM: Drug resistance is a significant cause of high mortality in ovarian cancer (OC) patients. The reverse transcriptase inhibitor azidothymidine (AZT) has been utilized as a treatment for tumors, but its role in OC treatment has not been revealed. The aim of the present in vitro study was to examine the influence of AZT on the growth of human OC cells and the involved proteins. MATERIALS AND METHODS: The proliferation, cell cycle distribution, extent of apoptosis, mitotic index, and terminal restriction fragment length were examined in three OC cell lines, CaOV3, TOV112D, and TOV21G, treated with AZT. RESULTS: AZT inhibited growth of the TOV21G and CaOV3 cell lines by regulating cell cycle distribution. Specifically, AZT caused G2/M phase arrest on TOV21G cells and S phase arrest on CaOV3 cells. In addition, AZT treatment induced up-regulation of p21 and p16 in the TOV21G and CaOV3 cell line, respectively. CONCLUSION: AZT inhibited cell proliferation in serous and clear cell OC via the regulation of cell cycle distribution.


Assuntos
Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Zidovudina/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia
3.
Eur J Med Chem ; 193: 112233, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32199136

RESUMO

Antimicrobial peptides (AMP) with anticancer activity have drawn remarkable attention in modern treatments. However, long peptide length and protease instability are the most addressing factors, which hampers their further development as therapeutic agents. In view of this, herein, we designed and synthesized a series of AZT-based cationic small molecule incorporating a variety of hydrophobic groups and cationic charges, including amine and guanidine groups to mimic the amphipathic structure of AMPs. These compounds were evaluated for their antibacterial activity against Gram-positive and Gram-negative bacteria. Through an extensive structure activity relationship study (SAR), we identified ADG-2e as the most potent antibacterial agent, which exhibited remarkable potency against drug resistant bacterial strains such as MRSA and MDRPA. Further, ADG-2e was examined for their anti-metastatic ability by investigating the cancer cell migration and invasiveness through scratch wound-healing assay and transwell invasive assay, respectively. In addition, time-lapse cell tracking analysis also performed for analyzing the cell movement pattern. Treatment of ADG-2e against metastatic breast cancer cells (MDA-MB-231) suppressed tumor cell migration by multi-directional lamellipodium formation, indicating their anti-metastatic potential. Thus, our cationic AZT based small molecules may evolve as an appealing class of antibacterial agents with anti-metastasis potential.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Zidovudina/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Cicatrização/efeitos dos fármacos , Zidovudina/síntese química , Zidovudina/química
4.
Oncol Rep ; 43(1): 260-269, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746437

RESUMO

The aim of the present study was to investigate the synergistic antitumor effects of emodin and 3'­azido­3'­deoxythymidine (AZT) on human chronic myeloid leukemia cells and to explore the possible underlying mechanisms. The K562 cells were treated with emodin and AZT, and the rates of cell inhibition and apoptosis were determined by MTT assay and flow cytometry, respectively. The mRNA expression of EGR1 was detected by reverse transcription­polymerase chain reaction (RT­PCR) analysis. The expression of EGR1 was silenced using siRNA, and then protein expression of ß­catenin was detected by western blotting. The results demonstrated that AZT enhanced the inhibitory effect of emodin in K562 cells. The IC50 of the emodin/AZT combination at 24, 48 or 72 h was 23.6/235.6, 10.2/101.6 or 5.9/58.5 µmol/l, respectively, which was significantly lower compared with the IC50 of emodin (all >32 µmol/l) or AZT (all >320 µmol/l) alone. There was a dose­dependent response to the combined emodin and AZT treatment, and the calculation of the combination index yielded values <1, demonstrating the synergistic effect of the combined treatment compared with the control (P<0.05). Furthermore, the combination of emodin and AZT increased apoptosis in K562 cells (P<0.05). Apoptosis was higher in the combination group compared with that of either treatment alone or control groups. The expression of early growth response­1 (EGR1) in K562 cells was upregulated in a time­dependent manner. The expression of EGR1 was higher in the combination group compared with that in the emodin or AZT alone groups. The expression of the Wnt/ß­catenin signaling pathway in the combination group was lower compared with that in the emodin or AZT alone groups. The expression of the Wnt/ß­catenin signaling pathway was significantly increased following EGR1 siRNA transfection. These data suggest that treating K562 cells with a combination of emodin and AZT exhibits reduced toxicity and improves therapeutic efficacy, and that the growth, inhibition, apoptosis and regulation of the Wnt/ß­catenin signaling pathway in human chronic myeloid leukemia cells by emodin and AZT may be associated with the expression of EGR1.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/genética , Emodina/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Via de Sinalização Wnt/efeitos dos fármacos , Zidovudina/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , beta Catenina/metabolismo
5.
J Pharm Biomed Anal ; 178: 112911, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31627078

RESUMO

Zidovudine (ZDV) and efavirenz (EFV), which belong to two separate classes of antiretroviral drugs, viz., NRTI and NNRTI, respectively, were subjected to different stability test conditions alone and in solid mixtures to evaluate possibility of interaction among them. The exposed samples were analyzed by high performance liquid chromatography (HPLC) using a C18 column and a PDA detector. Two new peaks were observed in the sample in which 50 µl CH3CN was added to increase the contact among the drugs, and which was subjected in open beaker to accelerated stability test condition of 40 °C/75%RH for 15 d. Subsequently, liquid chromatography-high resolution mass spectrometric (LC-HRMS) studies were carried out to obtain their accurate mass. The products were also isolated, and subjected to 1H, 13C, DEPT-135, COSY, HSQC and HMBC nuclear magnetic resonance (NMR) studies. The collective information allowed their structural characterization as isomeric cycloaddition products of the two drugs. As these were novel compounds, they were subjected to testing for cytotoxicity and in vitro anti-HIV-1 activity against primary isolates HIV-1UG070 (X4, subtype D) and HIV-1VB59 (R5, subtype C) in TZM-bl cell line. The two were found to show weak activity against the standard drugs. The reason was sought through molecular docking studies, which highlighted that it was perhaps their comparative bigger molecular size than the drugs of both classes used currently in HIV therapy. Being previously unknown molecules, their in silico physicochemical and ADMET properties were also evaluated using ADMET Predictor™ and TOPKAT software.


Assuntos
Fármacos Anti-HIV/farmacologia , Benzoxazinas/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Zidovudina/farmacologia , Alquinos , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Ciclopropanos , Combinação de Medicamentos , Estabilidade de Medicamentos , Humanos , Espectroscopia de Ressonância Magnética/métodos , Simulação de Acoplamento Molecular
6.
Sci Rep ; 9(1): 15857, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676833

RESUMO

HIV-associated nephropathy (HIVAN) is a rapidly progressive kidney disease that is caused by HIV infection of renal epithelial cells with subsequent expression of viral genes, including vpr. Antiretroviral therapy ameliorates HIVAN without eradicating HIV from the kidneys and the mechanism by which it protects kidneys is poorly understood. Since HIV protease inhibitors have "off target" cellular effects, we studied whether darunavir, the most commonly prescribed protease inhibitor, protects kidneys from HIV-induced injury via mechanisms independent of HIV protease and viral replication. Renal epithelial cells were transduced with lentiviruses encoding HIV (lacking protease and reverse transcriptase), Vpr, or vector control. Darunavir attenuated HIV and Vpr-induced activation of Stat3, Src, Erk, and cytokines, which are critical for HIVAN pathogenesis. We then studied HIV-transgenic mice, which develop HIVAN in the absence of HIV protease or reverse transcriptase. Mice were treated with darunavir, zidovudine, darunavir + zidovudine, or control. Darunavir and darunavir + zidovudine reduced albuminuria and histologic kidney injury and normalized expression of dysregulated proteins. RNA-seq analyses demonstrated that darunavir suppressed HIV-induced upregulation of immune response genes in human kidney cells. These data demonstrate that darunavir protects against HIV-induced renal injury via mechanisms that are independent of inhibition of HIV protease.


Assuntos
Nefropatia Associada a AIDS/prevenção & controle , Darunavir/farmacologia , Inibidores da Protease de HIV/farmacologia , HIV-1/metabolismo , Rim/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nefropatia Associada a AIDS/metabolismo , Nefropatia Associada a AIDS/patologia , Animais , Linhagem Celular , Humanos , Rim/patologia , Rim/virologia , Camundongos , Camundongos Transgênicos , Zidovudina/farmacologia
7.
Assay Drug Dev Technol ; 17(7): 322-329, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31634020

RESUMO

The central nervous system has been identified as an anatomical reservoir for HIV due the difficulties in delivering therapeutic agents into the brain and this complication results in HIV-associated neurocognitive disorder that persists in infected patients. The brain regions that are potentially exposed to tissue deficits due to HIV have been reported in previous reports; therefore, it is important to determine the drugs that can enter and localize in brain regions that are known to be susceptible to HIV neurodegeneration. Sprague-Dawley rats received intraperitoneal doses of zidovudine and lamivudine (50 mg kg-1). Mass spectrometry methods were used to determine the pharmacokinetics, of zidovudine and lamivudine, in the brain using liquid chromatography tandem mass spectrometry and mass spectrometry imaging (MSI), respectively. Zidovudine and lamivudine displayed complementary pharmacokinetic curves indicating a rapid absorption and blood-brain barrier penetration of both drugs reaching Cmax at 0.5 h after single dose. MSI of coronal brain sections showed that zidovudine and lamivudine are mostly distributed in corpus callosum, globus pallidus, striatum, and the neocortex region. Mass spectrometry techniques were used to demonstrate that zidovudine and lamivudine drugs are able to reach and localize in brain regions that are targets of HIV neurodegeneration in the brain.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/tratamento farmacológico , Lamivudina/farmacologia , Transtornos Neurocognitivos/tratamento farmacológico , Zidovudina/farmacologia , Animais , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/análise , Cromatografia Líquida , Feminino , Injeções Intraperitoneais , Lamivudina/administração & dosagem , Lamivudina/análise , Transtornos Neurocognitivos/virologia , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Distribuição Tecidual , Zidovudina/administração & dosagem , Zidovudina/análise
8.
J Fluoresc ; 29(5): 1257-1263, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31620936

RESUMO

Autofluorescence of the bone extracellular matrix (ECM) has not been widely explored although the ECM plays a very important role in bone development. In our research we focused on examining the bone matrix of very young animals due to the intense growth process during the first month of life. Structure images and fluorescence spectra of the bone surface were carried out using confocal fluorescence microscope Eclipse Ti-S inverted CLSM (NIKON, Japan) for compact tibia of healthy 7-, 14- and 28-day-old rat newborns after prenatal zidovudine administration in comparison with control. Spectral features of ECM autofluorescence were analyzed statistically by taking into consideration p < 0.05. The CLSM technique allows for simultaneous examination of the structure and autofluorescence from selected areas of the bone surface. Excessive autofluorescence of ECM after prenatal zidovudine administration influences bone growth incommensurably to the newborns' age. Therefore the possibility of an additional non-enzymatic mechanism of collagen cross-linking in the first two weeks of life of newborn rats prenatally treated with zidovudine has been considered. Our results suggest that ECM autofluorescence can be an indicator of bone development in the normal and pathological state.


Assuntos
Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Tíbia/citologia , Tíbia/crescimento & desenvolvimento , Zidovudina/farmacologia , Animais , Ratos , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Fatores de Tempo
9.
Artigo em Inglês | MEDLINE | ID: mdl-31481446

RESUMO

P-glycoprotein (ABCB1), an ATP-binding-cassette efflux transporter, limits intestinal absorption of its substrates and is a common site of drug-drug interactions (DDIs). ABCB1 has been suggested to interact with many antivirals used to treat HIV and/or chronic hepatitis C virus (HCV) infections. Using bidirectional transport experiments in Caco-2 cells and a recently established ex vivo model of accumulation in precision-cut intestinal slices (PCIS) prepared from rat ileum or human jejunum, we evaluated the potential of anti-HIV and anti-HCV antivirals to inhibit intestinal ABCB1. Lopinavir, ritonavir, saquinavir, atazanavir, maraviroc, ledipasvir, and daclatasvir inhibited the efflux of a model ABCB1 substrate, rhodamine 123 (RHD123), in Caco-2 cells and rat-derived PCIS. Lopinavir, ritonavir, saquinavir, and atazanavir also significantly inhibited RHD123 efflux in human-derived PCIS, while possible interindividual variability was observed in the inhibition of intestinal ABCB1 by maraviroc, ledipasvir, and daclatasvir. Abacavir, zidovudine, tenofovir disoproxil fumarate, etravirine, and rilpivirine did not inhibit intestinal ABCB1. In conclusion, using recently established ex vivo methods for measuring drug accumulation in rat- and human-derived PCIS, we have demonstrated that some antivirals have a high potential for DDIs on intestinal ABCB1. Our data help clarify the molecular mechanisms responsible for reported increases in the bioavailability of ABCB1 substrates, including antivirals and drugs prescribed to treat comorbidity. These results could help guide the selection of combination pharmacotherapies and/or suitable dosing schemes for patients infected with HIV and/or HCV.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Fármacos Anti-HIV/farmacologia , Antivirais/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Idoso , Animais , Sulfato de Atazanavir/farmacologia , Benzimidazóis/farmacologia , Células CACO-2/efeitos dos fármacos , Células CACO-2/metabolismo , Interações Medicamentosas , Feminino , Fluorenos/farmacologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Imidazóis/farmacologia , Intestinos/efeitos dos fármacos , Lopinavir/farmacologia , Masculino , Maraviroc/farmacologia , Pessoa de Meia-Idade , Ratos , Ratos Wistar , Ritonavir/farmacologia , Saquinavir/farmacologia , Zidovudina/farmacologia
10.
Curr HIV Res ; 17(5): 360-367, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31560292

RESUMO

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/métodos
11.
Eur J Pharm Biopharm ; 144: 91-100, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521715

RESUMO

We have previously demonstrated that the ester conjugation of zidovudine (AZT) with ursodeoxycholic acid (UDCA) allows to obtain a prodrug (U-AZT) which eludes the active efflux transporters (AET). This allows the prodrug to more efficiently permeates and remains in murine macrophages than the parent compound. Here we demonstrate that U-AZT can be formulated, by a nanoprecipitation method, as nanoparticle cores coated by bile acid salt (taurocholate or ursodeoxycholate) corona, without any other excipients. The U-AZT nanoparticles appeared spherical with a mean diameter of ∼200 nm and a zeta potential of ∼-55 mV. During the incubation (5 h) in fetal bovine serum, the ursodeoxycholate-coated nanoparticle size did not change. Differently, taurocholate-coated particle size was firstly reduced and then increased up to 800 µm, thus suggesting the high aptitude of these nanoparticles to interact with serum proteins. The in vitro uptake of taurocholate coated particles by murine macrophages was strongly higher than that of ursodeoxycholate-coated particles or free U-AZT (∼500% and ∼7000%, respectively). AZT was also detected in macrophages following the prodrug uptake, with the greatest amounts observed after the taurocholate-coated nanoparticle incubation. As macrophages in the subarachnoid spaces of cerebrospinal fluid (CSF) constitute one of the most unreachable HIV sanctuaries in the body, we also tested the ability of taurocholate-coated nanoparticles (i.e., nanoparticles highly internalized by macrophages) to reach them after their nasal administration in the presence or absence of chitosan. The results indicate that chitosan allowed to obtain a relatively high uptake (up to 4 µg/ml) of U-AZT in CSF. Taking into account that chitosan may promote the direct brain nanoparticle uptake, these findings can be considered an initial step toward the in vivo targeting of the subarachnoid macrophages by U-AZT prodrug.


Assuntos
Ácidos e Sais Biliares/química , Encéfalo/metabolismo , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Mucosa Nasal/metabolismo , Pró-Fármacos/farmacologia , Zidovudina/farmacologia , Administração Intranasal , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Linhagem Celular , Quitosana/química , Portadores de Fármacos/química , Excipientes/química , Camundongos , Nariz , Tamanho da Partícula , Ácido Ursodesoxicólico/química
12.
Mol Cell Biochem ; 462(1-2): 41-50, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31432386

RESUMO

Antiretroviral therapy (ART) has remarkably decreased HIV-related mortality. However, drug-resistant HIV variants pose a potential threat to the long-term success of ART. Both HIV mutants and host factors can cause HIV drug resistance. Using susceptible ACH2 cells chronically infected with HIV-1, we examined the effects of MAPK p38α on AZT resistance against reactivating HIV-1 replication that can be activated by HIV-1 superinfection. We found that HIV-1 superinfection induced more viral production, which was diminished by p38 inhibitor, SB203580, and by AZT in cells infected with non-AZT-resistant HIV-1 strain MN. p38α expression can resist action of AZT in inhibition of HIV-1 replication with increased expression of transcription factor, NF-ĸBp65, SP1, and c-Fos through activation of TCR-related pathways with upregulation of CD3, TCRα, TCRß, Zap-70, PKC, PLCγ1, GRB2, and PI3K/Akt expression. In HIV-1 MN superinfection under AZT treatment, expression of p38α led to HIV vif expression and inhibited APOBEC3G expression. We also investigated effects of p38α on gp130/JAK-STAT pathways, in which p38α increased expression of protein, gp130, EGFR, Jak2, STAT1, STAT3, STAT5, ras, and TF. p38α could induce apoptotic pathways with upregulation of Fas, FADD, Caspase-8, p53, and Bax, and downregulation of Bcl2 expression. These results indicate that p38α plays a positive role in reactivation of viral replication from HIV-1 latent infection and leads to HIV-1 AZT resistance. In conclusion, MAPKp38α can activate HIV-1 replication inhibited by AZT from HIV-1 latent infection and may be used as a latency reversal agent. The activation involves induction of several cell signaling pathways that are required for HIV-1 replication, which may be integrated into future viral remission strategies.


Assuntos
Farmacorresistência Viral/efeitos dos fármacos , HIV-1/fisiologia , Replicação Viral/efeitos dos fármacos , Zidovudina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Receptor gp130 de Citocina/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Janus Quinases/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/efeitos dos fármacos , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo
13.
Mater Sci Eng C Mater Biol Appl ; 103: 109771, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349486

RESUMO

Cancer treatment based anticancer drugs face serious obstacles. To prevail these obstacles, an effective targeted drug carrier can be imperative. This study aimed to design rationally an imprinting strategy for the carrying of a model anticancer drug, Azidothymidine via molecular imprinting technology. Considering the identity and affinity of monomers and cross-linkers to AZT, this work succeeded to establish an exclusive procedure to significantly improve the process of imprinting the Azidothymidine. Imprinting process was carried out on the surface of vinyl-modified silica coated Fe3O4 nanoparticles toward the delivery of azidothymidine to targeted tissue by external magnetic field. The resultant carrier was characterized by FT-IR, XRD, VSM, FESEM, EDX, BET, TGA. The AZT loading process on the nanocarrier is followed with Freundlich adsorption isotherm (QMAX:170 mg/g) and pseudo-second order fast adsorption kinetic (5 min). The release process of AZT from nanocarrier was fitted with First-Order and Higuchi dynamic model. Eventually, the involvement of magnetic nanocarrier was investigated on apoptosis in MCF-7 (cancer cell line) and MCF-10 (normal cell line). The cytotoxicity percentage on MCF-7 cells for magnetic nanocarrier was about 49 times greater than the azidothymidine, but did not affect MCF-10 cells. The corresponding results appropriately disclosed that the cytotoxicity of proposed nanocarrier on MCF-7 cells is through the caspase3 activity. The drug loading and release process as well as in-vitro studies of magnetic carrier were compared with bare carrier. This study indicates that the proposed magnetic carrier can be used as a promising drug carrier toward the breast cancer treatment.


Assuntos
Antineoplásicos , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos , Nanopartículas de Magnetita , Impressão Molecular , Zidovudina , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Feminino , Humanos , Células MCF-7 , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Zidovudina/química , Zidovudina/farmacologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-31160293

RESUMO

The Prestwick library was screened for antibacterial activity or "antibiotic resistance breaker" (ARB) potential against four species of Gram-negative pathogens. Discounting known antibacterials, the screen identified very few ARB hits, which were strain/drug specific. These ARB hits included antimetabolites (zidovudine, floxuridine, didanosine, and gemcitabine), anthracyclines (daunorubicin, mitoxantrone, and epirubicin), and psychoactive drugs (gabapentin, fluspirilene, and oxethazaine). These findings suggest that there are few approved drugs that could be directly repositioned as adjunct antibacterials, and these will need robust testing to validate efficacy.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Didanosina/farmacologia , Farmacorresistência Bacteriana Múltipla , Etanolaminas/farmacologia , Floxuridina/farmacologia , Bactérias Gram-Negativas/genética , Testes de Sensibilidade Microbiana , Mitoxantrona/farmacologia , Zidovudina/farmacologia
15.
Cell Death Dis ; 10(6): 390, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101804

RESUMO

Acute myeloid leukemia (AML) patients display dismal prognosis due to high prevalence of refractory and relapsed disease resulting from chemoresistance. Treatment protocols, primarily based on the anchor drug Cytarabine, remained chiefly unchanged in the past 50 years with no standardized salvage regimens. Herein we aimed at exploring potential pre-clinical treatment strategies to surmount Cytarabine resistance in human AML cells. We established Cytarabine-resistant sublines derived from human leukemia K562 and Kasumi cells, and characterized the expression of Cytarabine-related genes using real-time PCR and Western blot analyses to uncover the mechanisms underlying their Cytarabine resistance. This was followed by growth inhibition assays and isobologram analyses testing the sublines' sensitivity to the clinically approved drugs hydroxyurea (HU) and azidothymidine (AZT), compared to their parental cells. All Cytarabine-resistant sublines lost deoxycytidine kinase (dCK) expression, rendering them refractory to Cytarabine. Loss of dCK function involved dCK gene deletions and/or a novel frameshift mutation leading to dCK transcript degradation via nonsense-mediated decay. Cytarabine-resistant sublines displayed hypersensitivity to HU and AZT compared to parental cells; HU and AZT combinations exhibited a marked synergistic growth inhibition effect on leukemic cells, which was intensified upon acquisition of Cytarabine-resistance. In contrast, HU and AZT combination showed an antagonistic effect in non-malignant cells. Finally, HU and AZT synergism was demonstrated on peripheral blood specimens from AML patients. These findings identify a promising HU and AZT combination for the possible future treatment of relapsed and refractory AML, while sparing normal tissues from untoward toxicity.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Hidroxiureia/farmacologia , Leucemia Mieloide Aguda/patologia , Zidovudina/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citarabina/farmacologia , Dano ao DNA/efeitos dos fármacos , Desoxicitidina Quinase/genética , Desoxicitidina Quinase/metabolismo , Sinergismo Farmacológico , Histonas/metabolismo , Humanos , Hidroxiureia/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Ubiquitinação , Zidovudina/uso terapêutico
16.
PLoS Biol ; 17(4): e3000204, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30951520

RESUMO

Telomerase, a unique reverse transcriptase that specifically extends the ends of linear chromosomes, is up-regulated in the vast majority of cancer cells. Here, we show that an indole nucleotide analog, 5-methylcarboxyl-indolyl-2'-deoxyriboside 5'-triphosphate (5-MeCITP), functions as an inhibitor of telomerase activity. The crystal structure of 5-MeCITP bound to the Tribolium castaneum telomerase reverse transcriptase reveals an atypical interaction, in which the nucleobase is flipped in the active site. In this orientation, the methoxy group of 5-MeCITP extends out of the canonical active site to interact with a telomerase-specific hydrophobic pocket formed by motifs 1 and 2 in the fingers domain and T-motif in the RNA-binding domain of the telomerase reverse transcriptase. In vitro data show that 5-MeCITP inhibits telomerase with a similar potency as the clinically administered nucleoside analog reverse transcriptase inhibitor azidothymidine (AZT). In addition, cell-based studies show that treatment with the cell-permeable nucleoside counterpart of 5-MeCITP leads to telomere shortening in telomerase-positive cancer cells, while resulting in significantly lower cytotoxic effects in telomerase-negative cell lines when compared with AZT treatment.


Assuntos
Nucleosídeos/metabolismo , Telomerase/antagonistas & inibidores , Telomerase/fisiologia , Animais , Domínio Catalítico/efeitos dos fármacos , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Modelos Moleculares , Nucleosídeos/síntese química , Nucleosídeos/fisiologia , Nucleotídeos/síntese química , Nucleotídeos/metabolismo , RNA/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Telômero , Tribolium/genética , Tribolium/metabolismo , Zidovudina/metabolismo , Zidovudina/farmacologia
17.
J Pharmacol Sci ; 139(4): 275-279, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30928089

RESUMO

OBJECTIVE: This study aims to investigate the prevalence and types of drug resistance mutations among patients failing first-line antiretroviral therapy (ART). METHODS: Plasma samples from 112 patients with human immunodeficiency virus-1 (HIV-1) were collected for virus RNA extract and gene amplification. The mutations related to drug resistance were detected and the incidence was statistically analyzed, and the drug resistance rate against common drugs was also evaluated. RESULTS: 103 cases were successfully amplified, and the main drug resistance mutations in the reverse transcriptase (RT) region were M184V (50.49%), K103N (28.16%), Y181C (25.24%), and K65R (27.18%), while no drug main resistance mutation was found in the protease (PR) region. The incidence of drug resistance mutations was significantly different among patients with different ages, routes of infection, duration of treatment, initial ART regimens and viral load. The drug resistance rate to the common drugs was assessed, including Efavirenz (EFV, 71.84%), Nevirapine (NVP, 74.76%), Lamivudine (3TC, 66.02%), Zidovudine (AZT, 4.85%), Stavudine (D4T, 16.51%), and Tenofovir (TDF, 21.36%). CONCLUSION: The drug resistance mutations to NRTIs and NNRTIs are complex and highly prevalent, which was the leading cause of first-line ART failure. This study provides significant theoretical support for developing the second-line and third-line therapeutic schemes.


Assuntos
Terapia Antirretroviral de Alta Atividade , Antivirais/farmacologia , Benzoxazinas/farmacologia , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Mutação , Nevirapina/farmacologia , Adulto , Alquinos , Ciclopropanos , Feminino , Humanos , Incidência , Lamivudina/farmacologia , Masculino , Pessoa de Meia-Idade , Estavudina/farmacologia , Tenofovir/farmacologia , Falha de Tratamento , Carga Viral , Zidovudina/farmacologia
18.
Int J Antimicrob Agents ; 54(1): 55-61, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31034939

RESUMO

A phase 1 clinical study was performed to assess the pharmacokinetics and safety of intravenous (i.v.) administration of colistin methanesulfonate (CMS) and azidothymidine (AZT) alone and in combination. Seven healthy subjects received three (every 12 h) 1-h i.v. infusions of 4, 2 and 2 million international units (MIU) of CMS co-administered with 200, 100 and 100 mg of AZT, respectively. In an ex vivo study, urinary bactericidal titres (UBTs) and time-kill curve determinations were performed in artificial urine spiked with colistin sulfate and AZT according to median and minimum peak concentrations in urine measured after the first and third dose using four mcr-1-positive colistin-resistant and five colistin-susceptible Gram-negative isolates. Reciprocal UBTs for the different colistin concentrations obtained in urine ranged from 1-128 and 0-2 for colistin-susceptible and colistin-resistant isolates, respectively. Combination with AZT could increase UBTs up to two dilution steps each for the Enterobacteriaceae and Acinetobacter strains tested. In contrast, the combination had no activity against Pseudomonas strains. In time-kill curves, the combination showed bactericidal activity against colistin-resistant strains even when the substances alone were not bactericidal. Thus, combination of CMS with AZT shows promising synergistic activity against Gram-negative uropathogens, including colistin-resistant Enterobacteriaceae. According to the urinary bactericidal activity, a maintenance dosage of 2 MIU of CMS combined with 100 mg of AZT twice daily may be sufficient for the treatment of urinary tract infections (UTIs) caused by colistin-susceptible strains. However, the dosage requires optimisation for efficient treatment of UTIs caused by colistin-resistant strains.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Urina/microbiologia , Zidovudina/farmacologia , Acinetobacter/efeitos dos fármacos , Acinetobacter/crescimento & desenvolvimento , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Colistina/administração & dosagem , Colistina/efeitos adversos , Colistina/farmacocinética , Sinergismo Farmacológico , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Humanos , Pseudomonas/efeitos dos fármacos , Zidovudina/administração & dosagem , Zidovudina/efeitos adversos , Zidovudina/farmacocinética
19.
Cell Metab ; 29(4): 871-885.e5, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30853213

RESUMO

Mice deficient for SIRT6 exhibit a severely shortened lifespan, growth retardation, and highly elevated LINE1 (L1) activity. Here we report that SIRT6-deficient cells and tissues accumulate abundant cytoplasmic L1 cDNA, which triggers strong type I interferon response via activation of cGAS. Remarkably, nucleoside reverse-transcriptase inhibitors (NRTIs), which inhibit L1 retrotransposition, significantly improved health and lifespan of SIRT6 knockout mice and completely rescued type I interferon response. In tissue culture, inhibition of L1 with siRNA or NRTIs abrogated type I interferon response, in addition to a significant reduction of DNA damage markers. These results indicate that L1 activation contributes to the pathologies of SIRT6 knockout mice. Similarly, L1 transcription, cytoplasmic cDNA copy number, and type I interferons were elevated in the wild-type aged mice. As sterile inflammation is a hallmark of aging, we propose that modulating L1 activity may be an important strategy for attenuating age-related pathologies.


Assuntos
Inflamação/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sirtuínas/metabolismo , Fatores Etários , Animais , Didesoxinucleotídeos/administração & dosagem , Didesoxinucleotídeos/farmacologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Proteínas de Ligação a RNA/antagonistas & inibidores , Sirtuínas/deficiência , Estavudina/administração & dosagem , Estavudina/farmacologia , Nucleotídeos de Timina/administração & dosagem , Nucleotídeos de Timina/farmacologia , Zidovudina/administração & dosagem , Zidovudina/análogos & derivados , Zidovudina/farmacologia
20.
Int J Antimicrob Agents ; 53(6): 855-858, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30836109

RESUMO

BACKGROUND: New antibiotics are urgently needed to treat multi-drug resistant infections; however, production of novel antibiotics is diminishing. Synergistic combination drug therapy to enhance the activity of available antibiotics may improve management of patients with resistant infections. METHODS: Colistin-resistant Klebsiella pneumoniae isolates were collected from inpatients in 10 Greek hospitals and used to study combination activity of colistin plus azidothymidine. Combination activity was evaluated with the sum of fractional inhibitory concentrations (ΣFIC) using the mini checkerboard broth microdilution method. RESULTS: A hundred individual strains were tested. Synergistic activity was noted in 79% (79/100) of isolates and additive activity in the remaining 21% (21/100). ΣFIC50 and ΣFIC90 were 0.28 and 0.56, respectively. CONCLUSION: Colistin with azidothymidine exhibited promising synergistic activity against colistin-resistant Klebsiella pneumoniae isolates warranting further investigation of the combination.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Zidovudina/farmacologia , Infecção Hospitalar/microbiologia , Grécia , Hospitais , Humanos , Pacientes Internados , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana
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