RESUMO
N-(2-hydroxyphenyl)-2-propylpentanamide (HO-AAVPA) is a novel valproic acid derivative that has shown anti-proliferative activity against epitheloid cervix carcinoma (HeLa), rhabdomyosarcoma (A204), and several breast cancer cell lines. The aim of this research was to evaluate the pharmacokinetic profile and tissue distribution of HO-AAVPA in Wistar rats, as well as its human serum albumin binding potential by experimental and in silico methods. A single dose of HO-AAVPA was given to male rats by intravenous, intragastric or intraperitoneal routes at doses of 25, 100, and 100 mg/kg, respectively. Then, blood samples were drawn at predetermined intervals of time, and the HO-AAVPA concentration in the plasma was quantified with a validated HPLC method. The elimination half-life (t1/2) was approximately 222 min, and the systemic clearance (CL) and apparent volume of distribution (Vd) were 2.20 mL/min/kg and 0.70 L/kg, respectively. The absolute oral bioavailability of HO-AAVPA was 33.8%, and the binding rate of HO-AAVPA with rat plasma proteins was between 66.2% and 83.0%. Additionally, in silico, UV and Raman spectroscopy data showed weak interactions between the test compound and human serum albumin. Thus, the results that were obtained demonstrated that despite its low oral bioavailability, the potential anticancer agent HO-AAVPA exhibits acceptable pharmacokinetic properties that would allow it to reach its site of action and exert its pharmacological effect in Wistar Rats, and it has a convenient profile for future assays to evaluate its human applications.
Assuntos
Amidas/farmacocinética , Antineoplásicos/farmacocinética , Pentanos/farmacocinética , Albumina Sérica Humana/metabolismo , Ácido Valproico/farmacocinética , Administração Oral , Amidas/administração & dosagem , Amidas/sangue , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Sítios de Ligação , Disponibilidade Biológica , Injeções Intraperitoneais , Injeções Intravenosas , Masculino , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pentanos/administração & dosagem , Pentanos/sangue , Ligação Proteica , Ratos Wistar , Distribuição Tecidual , Ácido Valproico/administração & dosagem , Ácido Valproico/sangueRESUMO
Since the neuraminidase (NA) enzyme of the influenza A virus plays a key role in the process of release of new viral particles from a host cell, it is often a target for new drug design. The emergence of NA mutations, such as H275Y, has led to great resistance against neuraminidase inhibitors, including oseltamivir and zanamivir. Hence, we herein designed a set of derivatives by modifying the amine and/or carboxylic groups of oseltamivir. After being screened for their physicochemical (Lipinski's rule) and toxicological properties, the remaining compounds were submitted to molecular and theoretical studies. The docking simulations provided insights into NA recognition patterns, demonstrating that oseltamivir modified at the carboxylic moiety and coupled with anilines had higher affinity and a better binding pose for NA than the derivatives modified at the amine group. Based on these theoretical studies, the new oseltamivir derivatives may have higher affinity to mutant variants and possibly to other viral subtypes. Accordingly, two compounds were selected for synthesis, which together with their respective intermediates were evaluated for their cytotoxicity and antiviral activities. Their biological activity was then tested in cells infected with the A/Puerto Rico/916/34 (H1N1) influenza virus, and virus yield reduction assays were performed. Additionally, by measuring neuraminidase activity with the neuraminidase assay kit it was found that the compounds produced inhibitory activity on this enzyme. Finally, the infected cells were analysed with atomic force microscopy (AFM), observing morphological changes strongly suggesting that these compounds interfered with cellular release of viral particles.
Assuntos
Antivirais/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Neuraminidase/antagonistas & inibidores , Oseltamivir/farmacologia , Animais , Antivirais/química , Chlorocebus aethiops , Simulação por Computador , Cães , Farmacorresistência Viral , Células HeLa , Humanos , Técnicas In Vitro , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Microscopia de Força Atômica , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Oseltamivir/química , Células Vero , Proteínas Virais/antagonistas & inibidoresRESUMO
The neuraminidase (NA) epitope from the Mexican AH1N1 influenza virus was identified by using sequences registered at the GenBank during the peak of a pandemic (from April 2009 to October 2010). First, NA protein sequences were submitted for multiple alignment analysis, and their three-dimensional models (3-D) were then built by using homology modeling. The most common sequence (denominated wild-type) and its mutants were submitted to linear and nonlinear epitope predictors, which included the major histocompatibility complex type II (MHC II) and B-cell peptides. The epitope prediction was in accordance with evolutionary behavior and some protein structural properties. The latter included a low NA mutation rate, NA 3-D surface exposure, and the presence of high hindrance side chain residues. After selecting the epitope, docking studies and molecular dynamics (MD) simulations were used to explore interactions between the epitope and MHC II. Afterward, several experimental assays were performed to validate the theoretical study by using antibodies from humans (infected by pandemic H1N1) and rabbits (epitope vaccination). The results show 119 complete sequences that were grouped into 28 protein sequences according to their identity (one wild-type and 27 representative mutants (1-5 mutations)). The predictors yielded several epitopes, with the best fit being the one located in the C-terminal region. Theoretical methods demonstrated that the selected epitope reached the P4, P6, P7, and P9 pockets of MHC II, whereas the experimental evidence indicates that the epitope is recognized by human antibodies and also by rabbit antibodies immunized with the peptide.
Assuntos
Mapeamento de Epitopos/métodos , Epitopos de Linfócito B/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Neuraminidase/metabolismo , Infecções por Orthomyxoviridae/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/metabolismo , Biologia Computacional , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Influenza Humana/diagnóstico , México , Modelos Animais , Dados de Sequência Molecular , Mutação/genética , Neuraminidase/genética , Neuraminidase/imunologia , Ligação Proteica , Conformação Proteica , Coelhos , VacinaçãoRESUMO
Compounds with estrogenic effects that also inhibit platelet aggregation might be useful in reducing thrombotic events associated with estrogenic therapy. In this study, two aminoestrogens, Buame [N-(3-hydroxy-1,3,5(10)-estratrien-17ß-yl)-butylamine] and Diebud [N,N'-bis-(3-hydroxy-1,3,5(10)-estratrien-17ß-yl)-1,4-butanediamine], were synthesized and characterized using common analytical methods and spectrophotometric analyses. The location and orientation of these molecules on the estrogenic receptor α (ERα) were also evaluated. Platelet inhibitory effects were elucidated ADP-induced platelet aggregation and ADP- and collagen-induced ATP release. Molecular docking demonstrated that Buame can reach and bind to the ERα in the ligand binding domain (LBD) similar to 17ß-estradiol (co-crystallized ligand). On the other hand, Diebud binds only to the surface of ERα due to its high molecular volume compared to 17ß-estradiol and Buame.