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1.
Mol Divers ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37733244

RESUMO

Solving the worldwide problem of growing bacterial drug resistance will require a short-run and medium-term strategy. Structure-activity relationship (SAR) and quantitative SAR (QSAR) analyses have recently been utilized to reveal the molecular basis of the antibacterial activity and antibacterial spectrum of penicillins, the use of which is no longer solely empirical. Likewise, a more rational drug design can be achieved with cephalosporins, the largest group of ß-lactam antibiotics. The current contribution aimed to establish the molecular and physicochemical basis of the antibacterial activity of five generations of cephalosporins on methicillin-sensitive (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA). With SAR and QSAR analyses, the molecular portions that provide essential and additional antibacterial activity were identified. The substitutions with greater volume and polarity on the R2 side chain of the cephem nucleus increase potency on MSSA. The best effect is produced by substitutions with polar nitrogen atoms at the alpha-carbon (Cα). Substitutions with greater volume and polarity on the R1 side chain further enhance antibacterial activity. In contrast, the effect against MRSA seems to be independent of any substitution on R2 or at the Cα, while depending on the accessory portions with greater volume and polarity on R1.

2.
J Biol Inorg Chem ; 27(1): 121-131, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34806120

RESUMO

Levodopa is a cornerstone in Parkinson's disease treatment. Beneficial effects are mainly by binding on D2 receptors. Docking simulations of a set of compounds including well-known D2-ligands and a pool of Boron-Containing Compounds (BCC), particularly boroxazolidones with a tri/tetra-coordinated boron atom, were performed on the D2 Dopamine receptor (D2DR). Theoretical results yielded higher affinity of the compound DPBX, a Dopaboroxazolidone, than levodopa on D2DR. Essential interactions with residues in the third and sixth transmembrane domains of the D2DR appear to be crucial to induce and stabilize interactions in the active receptor state. Results from a motor performance evaluation of a murine model of Parkinson's disease agree with theoretical results, as DPBX showed similar efficacy to that of levodopa for diminishing MPTP-induced parkinsonism. This beneficial effect was disrupted with prior Risperidone (D2DR antagonist) administration, supporting the role of D2DR in the biological effect of DPBX. In addition, DPBX limited neuronal loss in substantia nigra in a similar manner to that of levodopa administration.


Assuntos
Levodopa , Doença de Parkinson , Animais , Boro , Levodopa/farmacologia , Levodopa/uso terapêutico , Camundongos , Doença de Parkinson/tratamento farmacológico
3.
Amino Acids ; 54(2): 215-228, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854957

RESUMO

The GABAergic and glutamatergic neurotransmission systems are involved in seizures and other disorders of the central nervous system (CNS). Benzofuran derivatives often serve as the core in drugs used to treat such neurological disorders. The aim of this study was to synthesize new γ-amino acids structurally related to GABA and derived from 2,3-disubstituted benzofurans, analyze in silico their potential toxicity, ADME properties, and affinity for the GluN1-GluN2A NMDA receptor, and evaluate their potential activity and neuronal mechanisms in a murine model of pentylenetetrazol (PTZ)- and 4-aminopyridine (4-AP)-induced seizures. The in silico analysis evidenced a low risk of toxicity for the test compounds as well as the probability that they can cross the blood-brain barrier (BBB) to reach their targets in the CNS. According to docking simulations, these compounds bind at the active site of the NMDA glutamate receptor with high affinity. The in vivo assays demonstrated that 4 protects against 4-AP-induced seizure episodes, suggesting negative allosteric modulation (NAMs) at the glutamatergic NMDA receptor. Contrarily, 3 (the regioisomer of 4) and its racemic derivatives (cis-2,3-dihydrobenzofurans) were previously described to exacerbate such episodes, pointing to their positive allosteric modulation (PAMs) of the same receptor.


Assuntos
Benzofuranos , Receptores de N-Metil-D-Aspartato , Aminoácidos , Animais , Benzofuranos/farmacologia , Ligantes , Camundongos , Pentilenotetrazol , Receptores de N-Metil-D-Aspartato/metabolismo
4.
Int J Mol Sci ; 23(6)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35328650

RESUMO

Preclinical and clinical evidence supports melatonin and its analogues as potential treatment for diseases involving cognitive deficit such as Alzheimer's disease. In this work, we evaluated by in silico studies a set of boron-containing melatonin analogues on MT1 and MT2 receptors. Then, we synthesized a compound (borolatonin) identified as potent agonist. After chemical characterization, its evaluation in a rat model with cognitive deficit showed that it induced ameliorative effects such as those induced by equimolar administration of melatonin in behavioral tests and in neuronal immunohistochemistry assays. Our results suggest the observed effects are by means of action on the melatonin system. Further studies are required to clarify the mechanism(s) of action, as the beneficial effects on disturbed memory by gonadectomy in male rats are attractive.


Assuntos
Melatonina , Receptor MT1 de Melatonina , Animais , Cognição , Masculino , Melatonina/farmacologia , Melatonina/uso terapêutico , Ratos , Receptor MT1 de Melatonina/agonistas , Receptor MT2 de Melatonina , Triptofano
5.
Parasitol Res ; 120(8): 2905-2918, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34195872

RESUMO

Current treatments for Chagas disease have a limited impact during the chronic stage and trigger severe side effects. Treatments target Trypanosoma cruzi, the etiological agent of the disease. The aims of this study were to evaluate the trypanocidal activity of four 2-phenylbenzothiazole derivatives (BZT1-4) in vitro by using the infectious and non-infectious forms of T. cruzi (trypomastigotes and epimastigotes, respectively) and to test the most promising compound (BZT4) in vivo in mice. Additionally, the toxicological profile and possible neuronal damage were examined. In relation to trypomastigotes, BZT4 was more selective and effective than the reference drug (benznidazole) during this infective stage, apparently due to the synergistic action of the CF3 and COOH substituents in the molecule. During the first few hours post-administration of BZT4, parasitemia decreased by 40% in an in vivo model of short-term treatment, but parasite levels later returned to the basal state. In the long-term assessment, the compound did not produce a significant antiparasitic effect, only attaining a 30% reduction in parasitemia by day 20 with the dose of 16 mg/kg. The toxicity test was based on repeated dosing of BZT4 (administered orally) during 21 days, which did not cause liver damage. However, the compound altered the concentration of proteins and the proteinic profile of neuronal cells in vitro, perhaps leading to an effect on the central nervous system. Further research on the low trypanocidal activity in vivo compared to the better in vitro effect could possibly facilitate molecular redesign to improve trypanocidal activity.


Assuntos
Doença de Chagas , Nitroimidazóis , Tiazóis , Tripanossomicidas , Trypanosoma cruzi , Animais , Doença de Chagas/tratamento farmacológico , Camundongos , Nitroimidazóis/uso terapêutico , Nitroimidazóis/toxicidade , Tiazóis/uso terapêutico , Tiazóis/toxicidade , Testes de Toxicidade , Tripanossomicidas/uso terapêutico , Tripanossomicidas/toxicidade , Trypanosoma cruzi/efeitos dos fármacos
6.
Artigo em Inglês | MEDLINE | ID: mdl-31712204

RESUMO

Chagas disease (CD) is a human infection caused by Trypanosoma cruzi CD was traditionally endemic to the Americas; however, due to migration it has spread to countries where it is not endemic. The current chemotherapy to treat CD induces several side effects, and its effectiveness in the chronic phase of the disease is controversial. In this contribution, substituted phenylbenzothiazole derivatives were synthesized and biologically evaluated as trypanocidal agents against Trypanosoma cruzi The trypanocidal activities of the most promising compounds were determined through systematic in vitro screening, and their modes of action were determined as well. The physicochemical-structural characteristics responsible for the trypanocidal effects were identified, and their possible therapeutic application in Chagas disease is discussed. Our results show that the fluorinated compound 2-methoxy-4-[5-(trifluoromethyl)-1,3-benzothiazol-2-yl] phenol (BT10) has the ability to inhibit the proliferation of epimastigotes [IC50(Epi) = 23.1 ± 1.75 µM] and intracellular forms of trypomastigotes [IC50(Tryp) = 8.5 ± 2.9 µM] and diminishes the infection index by more than 80%. In addition, BT10 has the ability to selectively fragment 68% of the kinetoplastid DNA compared with 5% of nucleus DNA. The mode of action for BT10 on T. cruzi suggests that the development of fluorinated phenylbenzothiazole with electron-withdrawing substituent is a promising strategy for the design of trypanocidal drugs.


Assuntos
Ciclo Celular/efeitos dos fármacos , Doença de Chagas/tratamento farmacológico , Tiazóis/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Células CHO , Doença de Chagas/parasitologia , Cricetulus , Halogenação , Humanos , Tiazóis/química , Tripanossomicidas/química , Trypanosoma cruzi/fisiologia
7.
Drug Dev Res ; 81(2): 256-266, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31875337

RESUMO

Alzheimer's disease (AD) is clearly linked to the decline of acetylcholine (ACh) effects in the brain. These effects are regulated by the hydrolytic action of acetylcholinesterase (AChE). Therefore, a central palliative treatment of AD is the administration of AChE inhibitors although additional mechanisms are currently described and tested for generating advantageous therapeutic strategies. In this work, we tested new arylamides and arylimides as potential inhibitors of AChE using in silico tools. Then, these compounds were tested in vitro, and two selected compounds, C7 and C8, as well as propranolol showed inhibition of AChE. In addition, they demonstrated an advantageous acute toxicity profile compared to that of galantamine as a reference AChE inhibitor. in vivo evaluation of memory performance enhancement was performed in an animal model of cognitive disturbance with each of these compounds and propranolol individually as well as each compound combined with propranolol. Memory improvement was observed in each case, but without a significant additive effect with the combinations.


Assuntos
Amidas/administração & dosagem , Inibidores da Colinesterase/administração & dosagem , Imidas/administração & dosagem , Transtornos da Memória/tratamento farmacológico , Amidas/síntese química , Amidas/química , Amidas/uso terapêutico , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/uso terapêutico , Simulação por Computador , Modelos Animais de Doenças , Quimioterapia Combinada , Humanos , Imidas/síntese química , Imidas/química , Imidas/uso terapêutico , Masculino , Conformação Molecular , Simulação de Acoplamento Molecular , Propranolol , Ratos
8.
J Mol Recognit ; 32(11): e2801, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31353677

RESUMO

In the design of 1-phenylbenzimidazoles as model cyclooxygenase (COX) inhibitors, docking to a series of crystallographic COX structures was performed to evaluate their potential for high-affinity binding and to reproduce the interaction profile of well-known COX inhibitors. The effect of ligand-specific induced fit on the calculations was also studied. To quantitatively compare the pattern of interactions of model compounds to the profile of several cocrystallized COX inhibitors, a geometric parameter, denominated ligand-receptor contact distance (LRCD), was developed. The interaction profile of several model complexes showed similarity to the profile of COX complexes with inhibitors such as iodosuprofen, iodoindomethacin, diclofenac, and flurbiprofen. Shaping of high-affinity binding sites upon ligand-specific induced fit mostly determined both the affinity and the binding mode of the ligands in the docking calculations. The results suggest potential of 1-phenylbenzimidazole derivatives as COX inhibitors on the basis of their predicted affinity and interaction profile to COX enzymes. The analyses also provided insights into the role of induced fit in COX enzymes. While inhibitors produce different local structural changes at the COX ligand binding site, induced fit allows inhibitors in diverse chemical classes to share characteristic interaction patterns that ensure key contacts to be achieved. Different interaction patterns may also be associated with different inhibitory mechanisms.


Assuntos
Benzimidazóis/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Benzimidazóis/química , Cristalografia por Raios X , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Bases de Dados de Proteínas , Indometacina/química , Indometacina/farmacologia , Ligantes , Simulação de Acoplamento Molecular , Prostaglandina-Endoperóxido Sintases/química , Termodinâmica
9.
Eur Biophys J ; 48(1): 83-97, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30386878

RESUMO

The design of beta2 adrenoceptor (ß2AR) agonists is attractive because of their wide-ranging applications in medicine, and the details of agonist interactions with ß2AR are interesting because it is considered a prototype for G-protein coupled receptors. Preclinical studies for agonist development have involved biological assays with guinea pigs due to a similar physiology to humans. Boron-containing Albuterol derivatives (BCADs) designed as bronchodilators have improved potency and efficacy compared with their boron-free precursor on guinea pig ß2ARs (gpß2ARs), and two of the BCADs (BR-AEA and boronterol) conserve these features on cells expressing human ß2ARs (hß2ARs). The aim of this study was to test the BCAD Politerol on gpß2ARs and hß2ARs in vitro and in silico. Politerol displayed higher potency and efficacy on gpß2AR than on hß2AR in experimental assays, possible explanations are provided based on molecular modeling, and molecular dynamics simulations of about 0.25 µs were performed for the free and bound states adding up to 2 µs in total. There were slight differences, particularly in the role of the boron atom, in the interactions of Politerol with gpß2ARs and hß2ARs, affecting movements of transmembrane domains 5-7, known to be pivotal in receptor activation. These findings could be instrumental in the design of compounds selective for hß2ARs.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/química , Agonistas de Receptores Adrenérgicos beta 2/metabolismo , Compostos de Boro/química , Compostos de Boro/metabolismo , Simulação de Dinâmica Molecular , Receptores Adrenérgicos beta 2/metabolismo , Animais , Células CHO , Cricetulus , Cobaias , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Receptores Adrenérgicos beta 2/química , Termodinâmica
10.
Mol Divers ; 23(2): 361-370, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30284107

RESUMO

Bladder relaxation through drug administration is an interesting topic in medicinal and combinatorial chemistry. In fact, compounds targeting catecholamine receptors [dopamine receptors and beta-adrenergic receptors (ßAR) expressed in the bladder] are among the compounds commonly employed for this purpose. In particular, recent investigations have tended to focus on the ß3-adrenoceptor (ß3AR) as a target in the treatment of urinary incontinence and other disorders. However, organoboron compounds have been suggested as potent and efficient agents on these drug targets. In this work, through a docking study, we identified the parameters that induce a theoretical improvement in the affinity and activity of the organoboron compounds on the catecholamine receptors expressed in the bladder. Then, the identified potential drug, a boron-containing dopa-derivative named DPBX-L-Dopa, was synthesized and characterized. This compound induces a relaxation on the smooth muscle of the rat bladder, behaving as a weak relaxant compared to isoproterenol but with similar efficacy to BRL377, a selective ß3AR agonist. However, unexpectedly, this effect was not blocked by propranolol or haloperidol at the concentrations at which they are able to block the catecholamine receptors in bladder tissue. In view of these results, the effect of DPBX-L-Dopa compound on the alpha 1 adrenergic receptors (α1AR) of aorta of the rats was also explored; however, no response of the tissue to this compound was obtained. The possible mechanisms of the action of this compound were explored and are discussed further.


Assuntos
Boro , Di-Hidroxifenilalanina , Parassimpatolíticos , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Boro/química , Boro/farmacologia , Di-Hidroxifenilalanina/química , Di-Hidroxifenilalanina/farmacologia , Desenho de Fármacos , Técnicas In Vitro , Masculino , Modelos Moleculares , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Parassimpatolíticos/química , Parassimpatolíticos/farmacologia , Ratos Wistar , Receptores de Catecolaminas , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologia
11.
Molecules ; 24(11)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151186

RESUMO

Two 2,3-disubstituted benzofurans (1 and 2), analogs of gamma-aminobutyric acid (GABA), were synthesized to obtain their 2,3-dihydro derivatives from the Pd/C-driven catalytic reduction of the double bond in the furanoid ring. The synthesis produced surprising by-products. Therefore, theoretical calculations of global and local reactivity were performed based on Pearson's hard and soft acids and bases (HSAB) principle to understand the regioselectivity that occurred in the reduction of the olefinic carbons of the compounds. Local electrophilicity (ωk) was the most useful parameter for explaining the selectivity of the polar reactions. This local parameter was defined with the condensed Fukui function and redefined with the electrophilic (Pk+) Parr function. The similar patterns of both resulting sets of values helped to demonstrate the electrophilic behavior (soft acid) of the olefinic carbons in these compounds. The theoretical calculations, nuclear magnetic resonance, and resonance hybrids showed the moieties in each compound that are most susceptible to reduction.


Assuntos
Benzofuranos/química , Modelos Químicos , Oxirredução , Teoria Quântica , Benzofuranos/síntese química , Catálise , Técnicas de Química Sintética , Espectroscopia de Ressonância Magnética , Estrutura Molecular
12.
Ren Fail ; 40(1): 92-98, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29299955

RESUMO

A worldwide public health problem is chronic kidney disease (CKD) presenting alarming epidemiological data. It currently affects about 10% of the adult population worldwide and has a high mortality rate. It is now known that oxidative stress represents one of the most important mechanisms in its pathophysiology, from the early stages to the terminal phase. Oxidation increases inflammation and reduces the capacity of NO• to relax vascular smooth muscle, in part by decreasing bioavailability of tetrahydrobiopterin (BH4), leading to endothelial dysfunction and high blood pressure, and due to the limited effectiveness of existing treatments, new drugs are needed to prevent and/or treat these mechanisms. The aim of this study was to test apocynin in a 5/6 nephrectomy mouse model of CKD to investigate whether its known antioxidant effect can improve the disease outcome. This effect results from the inhibition of NADPH oxidase and consequently a reduced production of the superoxide anion ([Formula: see text]). Animals were divided into five groups: sham, 5/6 nephrectomy only, and 5/6 nephrectomy followed by treatment with captopril, losartan or apocynin. The parameters evaluated were blood pressure and markers of oxidative stress ([Formula: see text]) and endothelial function (BH4). There were significantly lower levels of [Formula: see text] and a greater availability of serum BH4 in the apocynin-treated animals versus the control group and the two other drug treatments. The present findings suggest that apocynin in conjunction with a coadjuvant for modulating blood pressure may be useful for controlling the progression of CRF.


Assuntos
Acetofenonas/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Antioxidantes/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Insuficiência Renal Crônica/tratamento farmacológico , Acetofenonas/farmacologia , Adjuvantes Farmacêuticos/farmacologia , Adjuvantes Farmacêuticos/uso terapêutico , Animais , Anti-Hipertensivos/farmacologia , Antioxidantes/farmacologia , Captopril/farmacologia , Captopril/uso terapêutico , Modelos Animais de Doenças , Progressão da Doença , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Humanos , Losartan/farmacologia , Losartan/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Insuficiência Renal Crônica/etiologia , Resultado do Tratamento
13.
Molecules ; 23(5)2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747438

RESUMO

γ-Aminobutyric acid (GABA) is the most important inhibitory neurotransmitter in the central nervous system, and a deficiency of GABA is associated with serious neurological disorders. Due to its low lipophilicity, there has been an intensive search for new molecules with increased lipophilicity to cross the blood-brain barrier to raise GABA concentrations. We have designed and evaluated in vitro and in silico some new analogues of GABA, where the nitrogen atom at the γ-position is embedded in heterocyclic scaffolds and determined their inhibitory potential over the GABA-AT enzyme from Pseudomonas fluorescens. These modifications lead to compounds with inhibitory activity as it occurs with compounds 18a and 19a. The construction of Pseudomonas fluorescens and human GABA-AT models were carried out by homology modeling. Docking assays were done for these compounds over the GABA-AT enzyme models where 19a showed a strong interaction with both GABA-AT enzymes.


Assuntos
4-Aminobutirato Transaminase/antagonistas & inibidores , Simulação por Computador , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Modelos Moleculares , Pseudomonas fluorescens/enzimologia , Ácido gama-Aminobutírico/análogos & derivados , Domínio Catalítico , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Compostos Heterocíclicos/síntese química , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Eletricidade Estática
14.
Anticancer Drugs ; 27(6): 508-18, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26918391

RESUMO

N-ω-chloroacetyl-L-ornithine (NCAO) is an ornithine decarboxylase (ODC) inhibitor that is known to exert cytotoxic and antiproliferative effects on three neoplastic human cancer cell lines (HeLa, MCF-7, and HepG2). Here, we show that NCAO has antiproliferative activity in 13 cancer cell lines, of diverse tissue origin from human and mice, and in a mouse cancer model in vivo. All cell lines were sensitive to NCAO after 72 h of treatment (the EC50 ranged from 1 to 50.6 µmol/l). The Ca Ski cell line was the most sensitive (EC50=1.18±0.07 µmol/l) and MDA-MB-231 was the least sensitive (EC50=50.6±0.3 µmol/l). This ODC inhibitor showed selectivity for cancer cells, exerting almost no cytotoxic effect on the normal Vero cell line (EC50>1000 µmol/l). NCAO induced apoptosis and inhibited tumor cell migration in vitro. Furthermore, in vivo, this compound (at 50 and 100 mg/kg, daily intraperitoneal injection for 7 days) exerted potent antitumor activity against both solid and ascitic tumors in a mouse model using the myeloma (Ag8) cell line. At these same two doses, the toxicological evaluation showed that NCAO has no obvious systemic toxicity. The current results suggest that the antitumor activity is exerted by apoptosis related not only to a local but also a systemic cytotoxic effect exerted by NCAO on tumor cells. The applications for NCAO as an antitumor agent may be extensive; however, further studies are needed to ascertain the antitumor activity on other types of tumor in vivo and to determine the precise molecular mechanism of its activity.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Neoplasias/tratamento farmacológico , Ornitina/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Ascite/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Neoplasias/patologia , Ornitina/farmacologia , Testes de Toxicidade Subcrônica , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
15.
J Enzyme Inhib Med Chem ; 31(sup3): 140-149, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27483122

RESUMO

Epigenetic alterations are associated with cancer and their targeting is a promising approach for treatment of this disease. Among current epigenetic drugs, histone deacetylase (HDAC) inhibitors induce changes in gene expression that can lead to cell death in tumors. Valproic acid (VPA) is a HDAC inhibitor that has antitumor activity at mM range. However, it is known that VPA is a hepatotoxic drug. Therefore, the aim of this study was to design a set of VPA derivatives adding the arylamine core of the suberoylanilide hydroxamic acid (SAHA) with different substituents at its carboxyl group. These derivatives were submitted to docking simulations to select the most promising compound. The compound 2 (N-(2-hydroxyphenyl)-2-propylpentanamide) was the best candidate to be synthesized and evaluated in vitro as an anti-cancer agent against HeLa, rhabdomyosarcoma and breast cancer cell lines. Compound 2 showed a better IC50 (µM range) than VPA (mM range) on these cancer cells. And also, 2 was particularly effective on triple negative breast cancer cells. In conclusion, 2 is an example of drugs designed in silico that show biological properties against human cancer difficult to treat as triple negative breast cancer.


Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Simulação por Computador , Desenho de Fármacos , Pentanos/farmacologia , Rabdomiossarcoma/patologia , Ácido Valproico/análogos & derivados , Amidas/síntese química , Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Histona Desacetilases/metabolismo , Humanos , Células MCF-7 , Modelos Moleculares , Estrutura Molecular , Pentanos/síntese química , Pentanos/química , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
16.
Bioorg Med Chem Lett ; 25(4): 820-5, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25592716

RESUMO

The development of ß2 adrenoceptor (ß2AR) agonists is of increasing interest because of their wide-ranging applications in medicine, particularly for the treatment of pulmonary diseases. Regarding the relaxation of smooth muscle that lines airways of mammals, some boron-containing adducts have demonstrated greater potency and efficacy compared to well-known boron-free compounds. We herein report the design and synthesis as well as the chemical and pharmacological characterization of a new boron-containing compound: ((R)-6-((S)-2-(tert-butylammonio)-1-hydroxyethyl)-2-hydroxy-2-isobutyl-4H-benzo[d][1,3,2] dioxaborinin-2-uide). Compared to its precursor (salbutamol), this compound induced relaxation of smooth muscle in guinea pig tracheal rings with greater potency and efficacy (EC50⩽28.02nM). Theoretical studies suggest the potential selectivity of this boron containing compound on the orthosteric site of beta adrenoceptors and/or signaling pathways, as well as the importance of the tetracoordinated boron atom in its structure for binding recognition properties.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/química , Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Compostos de Boro/química , Compostos de Boro/farmacologia , Broncodilatadores/química , Broncodilatadores/farmacologia , Animais , Cobaias , Simulação de Acoplamento Molecular
17.
J Enzyme Inhib Med Chem ; 30(3): 345-53, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24939101

RESUMO

Many cancer cells have high expression of ornithine decarboxylase (ODC) and there is a concerted effort to seek new inhibitors of this enzyme. The aim of the study was to initially characterize the inhibition properties, then to evaluate the cytotoxicity/antiproliferative cell based activity of N-ω-chloroacetyl-l-ornithine (NCAO) on three human cancer cell lines. Results showed NCAO to be a reversible competitive ODC inhibitor (Ki = 59 µM) with cytotoxic and antiproliferative effects, which were concentration- and time-dependent. The EC50,72h of NCAO was 15.8, 17.5 and 10.1 µM for HeLa, MCF-7 and HepG2 cells, respectively. NCAO at 500 µM completely inhibited growth of all cancer cells at 48 h treatment, with almost no effect on normal cells. Putrescine reversed NCAO effects on MCF-7 and HeLa cells, indicating that this antiproliferative activity is due to ODC inhibition.


Assuntos
Antineoplásicos/farmacologia , Inibidores da Ornitina Descarboxilase/farmacologia , Ornitina Descarboxilase/metabolismo , Ornitina/análogos & derivados , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ativação Enzimática/efeitos dos fármacos , Células HeLa , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Células MCF-7 , Masculino , Estrutura Molecular , Ornitina/síntese química , Ornitina/química , Ornitina/farmacologia , Inibidores da Ornitina Descarboxilase/síntese química , Inibidores da Ornitina Descarboxilase/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Células Vero
18.
J Comput Aided Mol Des ; 28(12): 1217-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25298123

RESUMO

The aim of this study was to identify compounds that possess anticonvulsant activity by using a pentylenetetrazol (PTZ)-induced seizure model. Theoretical studies of a set of ligands, explored the binding affinities of the ligands for the GABA(A) receptor (GABA(A)R), including some benzodiazepines. The ligands satisfy the Lipinski rules and contain a pharmacophore core that has been previously reported to be a GABA(A)R activator. To select the ligands with the best physicochemical properties, all of the compounds were analyzed by quantum mechanics and the energies of the highest occupied molecular orbital and lowest unoccupied molecular orbital were determined. Docking calculations between the ligands and the GABA(A)R were used to identify the complexes with the highest Gibbs binding energies. The identified compound D1 (dibenzo(b,f)(1,4)diazocine-6,11(5H,12H)-dione) was synthesized, experimentally tested, and the GABA(A)R-D1 complex was submitted to 12-ns-long molecular dynamics (MD) simulations to corroborate the binding conformation obtained by docking techniques. MD simulations were also used to analyze the decomposition of the Gibbs binding energy of the residues involved in the stabilization of the complex. To validate our theoretical results, molecular docking and MD simulations were also performed for three reference compounds that are currently in commercial use: clonazepam (CLZ), zolpidem and eszopiclone. The theoretical results show that the GABA(A)R-D1, and GABA(A)R-CLZ complexes bind to the benzodiazepine binding site, share a similar map of binding residues, and have similar Gibbs binding energies and entropic components. Experimental studies using a PTZ-induced seizure model showed that D1 possesses similar activity to CLZ, which corroborates the predicted binding free energy identified by theoretical calculations.


Assuntos
Anticonvulsivantes/química , Antagonistas de Receptores de GABA-A/química , Receptores de GABA-A/química , Convulsões/tratamento farmacológico , Anticonvulsivantes/uso terapêutico , Sítios de Ligação , Antagonistas de Receptores de GABA-A/uso terapêutico , Humanos , Ligantes , Simulação de Dinâmica Molecular , Conformação Proteica , Receptores de GABA-A/metabolismo , Convulsões/patologia
19.
J Enzyme Inhib Med Chem ; 29(6): 884-94, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24517366

RESUMO

Herein we introduce the derivation of a mathematical expression to evaluate the dissociation constant of a mixture of stereoisomers in equal amounts (KdMIX), when the corresponding dissociation constants (Kd) or medium response (MR50) of the pure stereoisomers are known; the final equation takes the form of the harmonic mean. In order to validate the equation, we carried out a bibliographic search of experimental data of enantiomeric molecules with biological activity, considering the Kd's or MR50's of the isolated enantiomers as well as that of the racemate. The comparisons between the experimental dissociation constants of the mixtures (KdEXP or MR50EXP) and the calculated values (KdMIX or MR50MIX) were consistent; the similarity between these values is supported through statistical analyses of group comparison and simple linear correlation. The equation we obtained, which corresponds to the harmonic mean, was used to predict the values of KdMIX (or MR50MIX) or Kd (or MR50) in systems when only two of the experimental values are known: either the dissociation constants of both enantiomers or the Kd (or MR50) of one of the enantiomers and dissociation constant of the racemate.


Assuntos
Produtos Biológicos/química , Células Eucarióticas/efeitos dos fármacos , Modelos Estatísticos , Receptores de Superfície Celular/metabolismo , Animais , Produtos Biológicos/farmacologia , Células Eucarióticas/metabolismo , Humanos , Concentração Inibidora 50 , Cinética , Receptores de Superfície Celular/agonistas , Receptores de Superfície Celular/antagonistas & inibidores , Estereoisomerismo
20.
ChemMedChem ; 19(13): e202300615, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38554286

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder and the leading cause of dementia worldwide. It is characterized by a progressive decline in cholinergic neurotransmission. During the development of AD, acetylcholinesterase (AChE) binds to ß-amyloid peptides to form amyloid fibrils, which aggregate into plaque deposits. Meanwhile, tau proteins are hyperphosphorylated, forming neurofibrillary tangles (NFTs) that aggregate into inclusions. These complexes are cytotoxic for the brain, causing impairment of memory, attention, and cognition. AChE inhibitors are the main treatment for AD, but their effect is only palliative. This study aimed to design and synthesize novel benzofuran derivatives and evaluate their inhibition of AChE in vitro and in silico. Results: The seven synthesized benzofuran derivatives inhibited AChE in vitro. Benzofurans hydroxy ester 4, amino ester 5, and amido ester (±)-7 had the lowest inhibition constant (Ki) values and displayed good affinity for EeAChE in molecular docking. Six derivatives showed competitive inhibition, while the best compound (5: Ki=36.53 µM) exhibited uncompetitive inhibition. The amino, hydroxyl, amide, and ester groups of the ligands favored interaction with the enzyme by hydrogen bonds. Conclusion: Three benzofurans were promising AChE inhibitors with excellent Ki values. In future research on their their application to AD, 5 will be considered as the base structure.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Benzofuranos , Inibidores da Colinesterase , Simulação de Acoplamento Molecular , Benzofuranos/química , Benzofuranos/síntese química , Benzofuranos/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Doença de Alzheimer/tratamento farmacológico , Acetilcolinesterase/metabolismo , Humanos , Relação Estrutura-Atividade , Estrutura Molecular , Animais , Sítios de Ligação , Electrophorus , Relação Dose-Resposta a Droga
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