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1.
Inorg Chem ; 58(18): 12334-12347, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31464130

RESUMO

Lysosomal cysteine peptidase cathepsin B (catB) is an important tumor-promoting factor involved in tumor progression and metastasis representing a relevant target for the development of new antitumor agents. In the present study, we synthesized 11 ruthenium compounds bearing either the clinical agent nitroxoline that was previously identified as potent selective reversible inhibitor of catB activity or its derivatives. We demonstrated that organoruthenation is a viable strategy for obtaining highly effective and specific inhibitors of catB endo- and exopeptidase activity, as shown using enzyme kinetics and microscale thermophoresis. Furthermore, we showed that the novel metallodrugs by catB inhibition significantly impair processes of tumor progression in in vitro cell based functional assays at low noncytotoxic concentrations. Generally, by using metallodrugs we observed an improvement in catB inhibition, a reduction of extracellular matrix degradation and tumor cell invasion in comparison to free ligands, and a correlation with the reactivity of the monodentate halide leaving ligand.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Catepsina B/antagonistas & inibidores , Invasividade Neoplásica/prevenção & controle , Nitroquinolinas/farmacologia , Rutênio/farmacologia , Antineoplásicos/química , Neoplasias da Mama/patologia , Catepsina B/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Modelos Moleculares , Invasividade Neoplásica/patologia , Nitroquinolinas/química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Rutênio/química
2.
Anal Bioanal Chem ; 411(23): 6111-6118, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31367804

RESUMO

Application of a protease inhibitor, 4-(2-aminoethyl) benzenesulfonyl fluoride (AEBSF), during the cell culture process was demonstrated to effectively reduce proteolytic activity at a specific amino acid site during the production of an HIV-1 broadly neutralizing antibody (bNAb). However, the addition of AEBSF could potentially introduce some modifications to the bNAb protein. Experimental design from sample preparation to LC-MS characterization was performed using middle-up and bottom-up approaches to identify AEBSF-modified species for the bNAb using an AEBSF supplementation in the cell culture media. Modified species along with the unmodified control sample were also subjected to binding activity assessment. The results showed that two amino acids (Tyr177 and Lys250) were susceptible to AEBSF modification in the bNAb test articles but at a negligible level and not in the CDR regions, which therefore did not reduce the in vitro binding activity of the bNAb.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Imunoconjugados/imunologia , Inibidores de Proteases/imunologia , Sulfonas/imunologia , Sequência de Aminoácidos , Anticorpos Neutralizantes/química , Anticorpos Anti-HIV/química , Infecções por HIV/virologia , Humanos , Imunoconjugados/química , Inibidores de Proteases/química , Sulfonas/química , Espectrometria de Massas em Tandem
3.
J Chem Ecol ; 45(8): 693-707, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31367970

RESUMO

Crop domestication and selective breeding have altered plant defense mechanisms, influencing insect-plant interactions. A reduction in plant resistance/tolerance against herbivory is generally expected in domesticated species, however, limited efforts have been made to compare inducibility of plant defenses between wild and domesticated genotypes. In the present study, the inducibility of several plant defense mechanisms (e.g. defensive chemicals, trichomes, plant volatiles) were investigated, and the performance and preference of the herbivore Helicoverpa zea were measured in three different tomato genotypes; a) wild tomato, Solanum pimpinellifolium L. (accession LA 2093), b) cherry tomato, S. lycopersicum L. var. cerasiforme (accession Matts Wild Cherry), and c) cultivated tomato, S. lycopersicum L. var. Better Boy). Enhanced inducibility of defensive chemicals, trichomes, and plant volatiles in the cultivated tomato, and a higher level of constitutive plant resistance against herbivory in the wild genotype was observed. When comparing the responses of damaged vs. undamaged leaves, the percent reduction in larval growth was higher on damaged leaves from cultivated tomato, suggesting a higher induced resistance compared to other two genotypes. While all tomato genotypes exhibited increased volatile organic compound (VOCs) emissions in response to herbivory, the cultivated variety responded with generally higher levels of VOCs. Differences in VOC patterns may have influenced the ovipositional preferences, as H. zea female moths significantly preferred laying eggs on the cultivated versus the wild tomato genotypes. Selection of traits during domestication and selective breeding could alter allocation of resources, where plants selected for higher yield performance would allocate resources to defense only when attacked.


Assuntos
Lycopersicon esculentum/química , Mariposas/fisiologia , Solanum/química , Animais , Comportamento Animal/efeitos dos fármacos , Catecol Oxidase/metabolismo , Feminino , Genótipo , Herbivoria , Larva/fisiologia , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Oviposição/efeitos dos fármacos , Fenóis/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/análise , Análise de Componente Principal , Inibidores de Proteases/química , Solanum/genética , Solanum/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologia
4.
J Agric Food Chem ; 67(37): 10296-10305, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31464437

RESUMO

Grass pea is an orphan legume that is grown in many places in the world. It is a high-protein, drought-tolerant legume that is capable of surviving extreme environmental challenges and can be a sole food source during famine. However, grass pea produces the neurotoxin ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP), which can cause a neurological disease. This crop is promising as a food source for both animals and humans if ß-ODAP levels and other antinutritional factors such as protease inhibitors are lowered or removed. To understand more about these proteins, a proteomic analysis of grass pea was conducted using three different extraction methods to determine which was more efficient at isolating antinutritional factors. Seed proteins extracted with Tris-buffered saline (TBS), 30% ethanol, and 50% isopropanol were identified by mass spectrometry, resulting in the documentation of the most abundant proteins for each extraction method. Mass spectrometry spectral data and BLAST2GO analysis led to the identification of 1376 proteins from all extraction methods. The molecular function of the extracted proteins revealed distinctly different protein functional profiles. The majority of the TBS-extracted proteins were annotated with nutrient reservoir activity, while the isopropanol extraction yielded the highest percentage of endopeptidase proteinase inhibitors. Our results demonstrate that the 50% isopropanol extraction method was the most efficient at isolating antinutritional factors including protease inhibitors.


Assuntos
Fracionamento Químico/métodos , Fabaceae/química , Extratos Vegetais/isolamento & purificação , Inibidores de Proteases/isolamento & purificação , Sementes/química , Endopeptidases/química , Fabaceae/genética , Fabaceae/metabolismo , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Proteômica , Sementes/genética , Sementes/metabolismo
5.
Int J Mol Sci ; 20(11)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159170

RESUMO

The serine protease Caseinolytic protease subunit P (ClpP) plays an important role for protein homeostasis in bacteria and contributes to various developmental processes, as well as virulence. Therefore, ClpP is considered as a potential drug target in Gram-positive and Gram-negative bacteria. In this study, we utilized a biochemical assay to screen several small molecule libraries of approved and investigational drugs for Escherichia coli ClpP inhibitors. The approved drugs bortezomib, cefmetazole, cisplatin, as well as the investigational drug cDPCP, and the protease inhibitor 3,4-dichloroisocoumarin (3,4-DIC) emerged as ClpP inhibitors with IC50 values ranging between 0.04 and 31 µM. Compound profiling of the inhibitors revealed cefmetazole and cisplatin not to inhibit the serine protease bovine α-chymotrypsin, and for cefmetazole no cytotoxicity against three human cell lines was detected. Surface plasmon resonance studies demonstrated all novel ClpP inhibitors to bind covalently to ClpP. Investigation of the potential binding mode for cefmetazole using molecular docking suggested a dual covalent binding to Ser97 and Thr168. While only the antibiotic cefmetazole demonstrated an intrinsic antibacterial effect, cDPCP clearly delayed the bacterial growth recovery time upon chemically induced nitric oxide stress in a ClpP-dependent manner.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Descoberta de Drogas , Endopeptidase Clp/antagonistas & inibidores , Proteínas de Escherichia coli/antagonistas & inibidores , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Descoberta de Drogas/métodos , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade
6.
Molecules ; 24(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167364

RESUMO

Currently available drugs for treatment of glioblastoma, the most aggressive brain tumor, remain inefficient, thus a plethora of natural compounds have already been shown to have antimalignant effects. However, these have not been tested for their impact on tumor cells in their microenvironment-simulated cell models, e.g., mesenchymal stem cells in coculture with glioblastoma cell U87 (GB). Mesenchymal stem cells (MSC) chemotactically infiltrate the glioblastoma microenvironment. Our previous studies have shown that bone-marrow derived MSCs impair U87 growth and invasion via paracrine and cell-cell contact-mediated cross-talk. Here, we report on a plant-derived protein, obtained from Crataeva tapia tree Bark Lectin (CrataBL), having protease inhibitory/lectin activities, and demonstrate its effects on glioblastoma cells U87 alone and their cocultures with MSCs. CrataBL inhibited U87 cell invasion and adhesion. Using a simplified model of the stromal microenvironment, i.e., GB/MSC direct cocultures, we demonstrated that CrataBL, when added in increased concentrations, caused cell cycle arrest and decreased cocultured cells' viability and proliferation, but not invasion. The cocultured cells' phenotypes were affected by CrataBL via a variety of secreted immunomodulatory cytokines, i.e., G-CSF, GM-CSF, IL-6, IL-8, and VEGF. We hypothesize that CrataBL plays a role by boosting the modulatory effects of MSCs on these glioblastoma cell lines and thus the effects of this and other natural lectins and/or inhibitors would certainly be different in the tumor microenvironment compared to tumor cells alone. We have provided clear evidence that it makes much more sense testing these potential therapeutic adjuvants in cocultures, mimicking heterogeneous tumor-stroma interactions with cancer cells in vivo. As such, CrataBL is suggested as a new candidate to approach adjuvant treatment of this deadly tumor.


Assuntos
Capparaceae/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Inibidores de Proteases/farmacologia , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Citocinas/biossíntese , Glioblastoma/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Metaloproteases/antagonistas & inibidores , Óxido Nítrico/biossíntese , Extratos Vegetais/química , Lectinas de Plantas/química , Inibidores de Proteases/química
7.
Phys Chem Chem Phys ; 21(27): 14945-14956, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31236554

RESUMO

Zika virus (ZIKV) infection has become a global public health problem, associated with microcephaly in newborns and Guillain-Barré syndrome in adults. Currently, there are no commercially available anti-ZIKV drugs. The viral protease NS2B/NS3, which is involved in viral replication and maturation, is a potential drug target. Peptidomimetic aldehyde inhibitors bind covalently to the catalytic S135 of the NS3 protease. Here, we apply hybrid quantum mechanics/molecular mechanics (QM/MM) free-energy simulations at the PDDG-PM3/ff14SB level to investigate the inhibition mechanism of the ZIKV protease by a dipeptidyl aldehyde inhibitor (acyl-KR-aldehyde). The results show that proton transfer from the catalytic S135 to H51 occurs in concert with nucleophilic addition on the aldehyde warhead by S135. The anionic covalent complex between the dipeptidyl aldehyde and the ZIKV protease is analogous to the tetrahedral intermediate for substrate hydrolysis. Spontaneous protonation by H51 forms the hemiacetal. In addition, we use correlated ab initio QM/MM potential energy path calculations at levels up to LCCSD(T)/(aug)-cc-pVTZ to obtain accurate potential energy profiles of the reaction, which also support a concerted mechanism. These results provide detailed insight into the mechanism of ZIKV protease inhibition by a peptidyl aldehyde inhibitor, which will guide in the design of inhibitors.


Assuntos
Aldeídos/farmacologia , Serina Proteases/metabolismo , Zika virus/enzimologia , Aldeídos/química , Dipeptídeos/química , Dipeptídeos/farmacologia , Desenho de Drogas , Transferência de Energia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Teoria Quântica
8.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 5): 385-391, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045568

RESUMO

The inhibition of kallikrein 5 (KLK5) has been identified as a potential strategy for treatment of the genetic skin disorder Netherton syndrome, in which loss-of-function mutations in the SPINK5 gene lead to down-regulation of the endogenous inhibitor LEKTI-1 and profound skin-barrier defects with severe allergic manifestations. To aid in the development of a medicine for this target, an X-ray crystallographic system was developed to facilitate fragment-guided chemistry and knowledge-based drug-discovery approaches. Here, the development of a surrogate crystallographic system in place of KLK5, which proved to be challenging to crystallize, is described. The biochemical robustness of the crystallographic surrogate and the suitability of the system for the study of small nonpeptidic fragments and lead-like molecules are demonstrated.


Assuntos
Benzamidinas/química , Calicreínas/química , Inibidores de Proteases/química , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Baculoviridae/metabolismo , Benzamidinas/farmacologia , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Descoberta de Drogas , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Calicreínas/antagonistas & inibidores , Calicreínas/genética , Calicreínas/metabolismo , Cinética , Modelos Moleculares , Mutação , Síndrome de Netherton/tratamento farmacológico , Síndrome de Netherton/enzimologia , Inibidores de Proteases/farmacologia , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Sf9 , Spodoptera , Eletricidade Estática , Especificidade por Substrato
9.
Carbohydr Polym ; 217: 232-239, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079681

RESUMO

Heparan sulfate (HS) and heparin, representative members of the glycosaminoglycans, possess distinct biological functions in terms of their specific interactions with hundreds of binding proteins. However, the structural properties of HS and heparin are complex due to their variable repeating motifs, different chain lengths and sulfation patterns. A concise chemoenzymatic approach has been developed to obtain well-defined low molecular weight (LMW) HS analogues. Pasteurella multocida heparosan synthase-2 (PmHS2) was utilized to fabricate the HS backbones with controllable chain lengths ranging from 14mer to 26mer. Moreover, regioselective and overall sulfation were conducted by chemical approach. The persulfated HS analogues exhibited more potent beta-site amyloid precursor protein (APP)-cleaving enzyme-1 (BACE-1) inhibitory activity than heparin and enoxaparin, and enhanced BACE-1 inhibitions were also found with the increasing molecular size of the HS analogues. This approach supplies the promising LMW HS analogues for the potential development of novel anti-Alzheimer's drugs.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Heparitina Sulfato/análogos & derivados , Inibidores de Proteases/química , Sequência de Carboidratos , Glicosiltransferases/química , Heparitina Sulfato/síntese química , Humanos , Peso Molecular , Pasteurella multocida/enzimologia , Inibidores de Proteases/síntese química
10.
Chem Biol Interact ; 307: 105-115, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31054283

RESUMO

Neutral endopeptidase (NEP) is an enzyme implicated in development of different tumors, e.g. colorectal cancer (CRC). In this study, the anti-cancer effects of NEP inhibitors, thiorphan (synthetic compound) and sialorphin (naturally occurring pentapeptide) on CRC cells were investigated. Moreover, we synthesized some derivatives of sialorphin (alanine scan analogues: AHNPR, QANPR, QHAPR, QHNAR; N-acetylated sialorphin; C-amidated sialorphin, and C-amidated alanine scan analogues) to examine the biological activity of these inhibitors on CRC cells. The cytotoxic activity of the NEP inhibitors against CRC cell lines (SW620 and LS180) and normal human fibroblasts (HSF) was evaluated. Additionally, the influence of NEP inhibitors on proliferation, cell cycle progression, induction of apoptosis, and the level of phosphorylation of MAP kinases and mTORC1 signaling pathway proteins in CRC cells were examined. The NEP inhibitors were non-cytotoxic to HSF cells; however, most of them slightly decreased the viability and inhibited proliferation of CRC cells. The N-acetylation or C-amidation of sialorphin or its alanine scan analogues resulted in decreased or abolished anti-proliferative activity of the NEP inhibitors towards the CRC cells. Additionally, thiorphan and sialorphin enhanced the anti-proliferative activity of other CRC-cell growth inhibitors (atrial natriuretic peptide-ANP and melphalan-MEL). The mechanisms involved in the anti-proliferative effects of the tested inhibitors were mediated via NEP and associated with induction of cell cycle arrest in the G0/G1 phase, increased activity of ERK1/2, and a reduced level of phosphorylation of mTOR (Ser2448), 4E-BP1, and p70S6K. However, the NEP inhibitors did not induce apoptosis in the CRC cells. These results have indicated that thiorphan and sialorphin or its derivatives AHNPR, QANPR, QHAPR, and QHNAR have the potential to be used as agents in treatment of patients with CRC.


Assuntos
Proliferação de Células/efeitos dos fármacos , Endopeptidases/metabolismo , Peptídeos/farmacologia , Inibidores de Proteases/farmacologia , Tiorfano/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Endopeptidases/química , Endopeptidases/genética , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Peptídeos/síntese química , Peptídeos/química , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteases/química , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Tiorfano/química
11.
J Agric Food Chem ; 67(22): 6432-6444, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31095381

RESUMO

Liquid feeding strategies have been devised with the aim of enhancing grain nutrient availability for livestock. It is characterized by a steeping/soaking period that softens the grains and initiates mobilization of seed storage reserves. The present study uses 2D gel-based proteomics to investigate the role of proteolysis and reduction by thioredoxins over a 48 h steeping period by monitoring protein abundance dynamics in barley-based liquid feed samples supplemented with either protease inhibitors or NADPH-dependent thioredoxin reductase/thioredoxin (NTR/Trx). Several full-length storage proteins were only identified in the water-extractable fraction of feed containing protease inhibitors, illustrating significant inhibition of proteolytic activities arising during the steeping period. Application of functional NTR/Trx to liquid feed reductively increased the solubility of known and potentially new Trx-target proteins, e.g., outer membrane protein X, and their susceptibility to proteolysis. Thus, the NTR/Trx system exhibits important potential as a feed additive to enhance nutrient digestibility in monogastric animals.


Assuntos
Ração Animal/análise , Hordeum/enzimologia , Proteínas de Plantas/química , Tiorredoxina Dissulfeto Redutase/química , Tiorredoxinas/química , Eletroforese em Gel Bidimensional , Manipulação de Alimentos , Hordeum/química , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Proteínas de Plantas/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Proteômica , Sementes/química , Sementes/enzimologia , Tiorredoxina Dissulfeto Redutase/metabolismo , Tiorredoxinas/metabolismo
12.
Comput Biol Chem ; 80: 292-306, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31054542

RESUMO

Human meprin beta metalloprotease, a small subgroup of the astacin family, is a potent drug target for the treatment of several disorders such as fibrosis, neurodegenerative disease in particular Alzheimer and inflammatory bowel diseases. In this study, a ligand-based pharmacophore approach has been used for the selection of potentially active compounds to understand the inhibitory activities of meprin-ß by using the sulfonamide scaffold based inhibitors. Using this dataset, a pharmacophore model (Hypo1) was selected on the basis of a highest correlation coefficient (0.959), lowest total cost (105.89) and lowest root mean square deviation (1.31 Å) values. All the pharmacophore hypotheses generated from the candidate inhibitors comprised four features: two hydrogen-bond acceptor, one hydrogen-bond donor and one zinc binder feature. The best validated pharmacophore model (Hypo1) was used for virtual screening of compounds from several databases. The selective hit compounds were filtered by drug likeness property, acceptable ADMET profile, molecular docking and DFT study. Molecular dynamic simulations with the final 10 hit compounds revealed that a large number of non-covalent interactions were formed with the active site and specificity sub-pockets of the meprin beta metalloprotease. This study assists in the development of the new lead molecules as well as gives a better understanding of their interaction with meprin-ß.


Assuntos
Metaloendopeptidases/química , Inibidores de Proteases/química , Sulfonamidas/química , Domínio Catalítico , Conjuntos de Dados como Assunto , Teoria da Densidade Funcional , Desenho de Drogas , Humanos , Ligantes , Metaloendopeptidases/metabolismo , Modelos Químicos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases/metabolismo , Ligação Proteica , Sulfonamidas/metabolismo
13.
Fish Shellfish Immunol ; 89: 437-447, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980916

RESUMO

Proteinase inhibitors with the ability to inhibit specific proteinases are usually closely connected with the immune system. Interestingly, proteinase inhibitors are also a common ingredient in the organic matrix of mollusk shells. However, the molecular mechanism that underlies the role of proteinase inhibitors in immune system and shell mineralization is poorly known. In this study, a Kunitz serine proteinase inhibitor (HcKuPI) was isolated from the mussel Hyriopsis cumingii. HcKuPI was specifically expressed in dorsal epithelial cells of the mantle pallium and HcKuPI dsRNA injection caused an irregular surface and disordered deposition on the aragonite tablets of the nacreous layer. These results indicated that HcKuPI plays a vital role in shell nacreous layer biomineralization. Moreover, the expression pattern of HcKuPI during LPS challenge and pearl formation indicated its involvement in the antimicrobial process during pearl sac formation and nacre tablets accumulation during pearl formation. In the in vitro calcium carbonate crystallization assay, the addition of GST-HcKuPI increased the precipitation rate of calcium carbonate and induced the crystal overgrowth of calcium carbonate. Taken together, these results indicate that HcKuPI is involved in antimicrobial process during pearl formation, and participates in calcium carbonate deposition acceleration and morphological regulation of the crystals during nacreous layer formation. These findings extend our knowledge of the role of proteinase inhibitors in immune system and shell biomineralization.


Assuntos
Antibacterianos/metabolismo , Carbonato de Cálcio/metabolismo , Nácar/metabolismo , Inibidores de Proteases , Unionidae/genética , Unionidae/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Unionidae/metabolismo
14.
Crit Rev Biochem Mol Biol ; 54(1): 11-26, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30821513

RESUMO

Direct acting antivirals have dramatically increased the efficacy and tolerability of hepatitis C treatment, but drug resistance has emerged with some of these inhibitors, including nonstructural protein 3/4 A protease inhibitors (PIs). Although many co-crystal structures of PIs with the NS3/4A protease have been reported, a systematic review of these crystal structures in the context of the rapidly emerging drug resistance especially for early PIs has not been performed. To provide a framework for designing better inhibitors with higher barriers to resistance, we performed a quantitative structural analysis using co-crystal structures and models of HCV NS3/4A protease in complex with natural substrates and inhibitors. By comparing substrate structural motifs and active site interactions with inhibitor recognition, we observed that the selection of drug resistance mutations correlates with how inhibitors deviate from viral substrates in molecular recognition. Based on this observation, we conclude that guiding the design process with native substrate recognition features is likely to lead to more robust small molecule inhibitors with decreased susceptibility to resistance.


Assuntos
Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Domínio Catalítico/efeitos dos fármacos , Hepacivirus/metabolismo , Hepatite C/virologia , Humanos , Inibidores de Proteases/química , Conformação Proteica/efeitos dos fármacos , Serina Proteases/química , Serina Proteases/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
15.
Yakugaku Zasshi ; 139(5): 827-835, 2019 May 01.
Artigo em Japonês | MEDLINE | ID: mdl-30842349

RESUMO

Proteolysis mediated by the ubiquitin-proteome system plays an important role in cancer. Recently, a deubiquitinating enzyme, ubiquitin-specific protease 7 (USP7) has attracted attention as a key regulator of the p53-human double minute 2 (HDM2) pathway in cancer cells. Although some USP7 enzyme inhibitors have been identified, issues related to activity and selectivity prevent their therapeutic application. In this study, we aimed to search for novel USP7-HDM2 protein-protein interaction (PPI) inhibitors that do not affect the USP7 enzyme activity. Using the fragment-mapping program Fsubsite and the canonical subsite-fragment database (CSFDB) developed in our laboratory, we mapped a variety of fragments onto USP7 protein and constructed 3D-pharmacophore models based on the arrangement patterns of the mapped fragments. Finally, we performed 3D pharmacophore-based virtual screening of a commercial compound database and successfully selected promising USP7-HDM2 PPI inhibitor candidates.


Assuntos
Antineoplásicos , Simulação por Computador , Descoberta de Drogas , Inibidores de Proteases , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-mdm2 , Mapeamento por Restrição/métodos , Peptidase 7 Específica de Ubiquitina , Modelos Moleculares , Inibidores de Proteases/química , Estrutura Quaternária de Proteína , Proteólise , Proteínas Proto-Oncogênicas c-mdm2/química , Peptidase 7 Específica de Ubiquitina/química
16.
Eur J Med Chem ; 168: 447-460, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30844608

RESUMO

A new series of 4-phenylcoumarin derivatives was synthesized starting from (2-oxo-4-phenyl-2H-chromen-7-yloxy) acetic acid hydrazide 3. Evaluation of the target compounds for their antiviral activity against hepatitis A virus revealed that the ethylthiosemicarbazide derivative 7b was the most potent virucidal agent (IC50 = 3.1 µg/ml, TI = 83). The Schiff's bases 14c and 14b demonstrated the highest virustatic effects against viral adsorption and replication, respectively (14c; IC50 = 8.5 µg/ml, TI = 88 and 14b; IC50 = 10.7 µg/ml, TI = 91). Furthermore, compounds 7b, 14b and 14c were tested against HAV 3C protease and showed significant inhibition effects (Ki = 1.903, 0.104 and 0.217 µM, respectively). The remarkable inhibitory effect expressed by the three target compounds against HAV 3C protease prompted us to expand our research on HRV 3C protease, a structurally related enzyme of the same family, and interestingly, the three target compounds displayed significant inhibitory effect against HRV 3C protease (IC50 = 16.10, 4.13 and 6.30 µM, respectively). Moreover, the active compounds 7b, 14b and 14c were docked within the pocket site of HAV 3C protease (PDB code: 2HAL) illustrating a strong H-profile with the key amino acids Gly170 and Cys172 similar to the co-crystallized ligand. Furthermore, 3D-pharmacophore and quantitative structure activity relationship (QSAR) models were generated to explore the structural requirements for the observed antiviral activity.


Assuntos
Antivirais/farmacologia , Cumarínicos/farmacologia , Desenho de Drogas , Vírus da Hepatite A/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Proteínas Virais/antagonistas & inibidores , Antivirais/síntese química , Antivirais/química , Cumarínicos/síntese química , Cumarínicos/química , Cisteína Endopeptidases/metabolismo , Relação Dose-Resposta a Droga , Vírus da Hepatite A/metabolismo , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Relação Quantitativa Estrutura-Atividade , Proteínas Virais/metabolismo
17.
Viruses ; 11(2)2019 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-30823509

RESUMO

Proteases are a major enzyme group playing important roles in a wide variety of biological processes in life forms ranging from viruses to mammalians. The aberrant activity of proteases can lead to various diseases; consequently, host proteases have been the focus of intense investigation as potential therapeutic targets. A wide range of viruses encode proteases which play an essential role in viral replication and, therefore, constitute attractive targets for the development of antiviral therapeutics. There are numerous examples of successful drug development targeting cellular and viral proteases, including antivirals against human immunodeficiency virus and hepatitis C virus. Most FDA-approved antiviral agents are peptidomimetics and macrocyclic compounds that interact with the active site of a targeted protease. Norovirus proteases are cysteine proteases that contain a chymotrypsin-like fold in their 3D structures. This review focuses on our group's efforts related to the development of norovirus protease inhibitors as potential anti-norovirus therapeutics. These protease inhibitors are rationally designed transition-state inhibitors encompassing dipeptidyl, tripeptidyl and macrocyclic compounds. Highly effective inhibitors validated in X-ray co-crystallization, enzyme and cell-based assays, as well as an animal model, were generated by launching an optimization campaign utilizing the initial hit compounds. A prodrug approach was also explored to improve the pharmacokinetics (PK) of the identified inhibitors.


Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Norovirus/enzimologia , Replicação Viral/efeitos dos fármacos , Antivirais/química , Infecções por Caliciviridae/tratamento farmacológico , Modelos Moleculares , Peptídeo Hidrolases/metabolismo , Peptidomiméticos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Conformação Proteica , Proteínas Virais
18.
J Pept Sci ; 25(4): e3154, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30734395

RESUMO

Cathepsin D (Cath D) is overexpressed and hypersecreted by malignant tumors and involved in the progress of tumor invasion, proliferation, metastasis, and apoptosis. Cath D has been considered as a potential target to treat cancer. Our previous studies revealed that tasiamide B derivatives TB-9 and TB-11 exhibited high potent inhibition against Cath D and other aspartic proteases, but their molecular weights are still high, and the role of each residue is unknown yet. Based on this, two series of tasiamide B derivatives have been designed, synthesized, and evaluated for their inhibitory activity against Cath D/Cath E/BACE1. Enzymatic assays revealed that the target compound 1 with lower molecule weight showed good inhibitory activity against Cath D with IC50 of 3.29 nM and satisfactory selectivity over Cath E (72-fold) and BACE1 (295-fold), which could be a valuable template for the design of highly potent and selective Cath D inhibitors.


Assuntos
Catepsina D/antagonistas & inibidores , Desenho de Drogas , Oligopeptídeos/farmacologia , Inibidores de Proteases/farmacologia , Catepsina D/metabolismo , Relação Dose-Resposta a Droga , Estrutura Molecular , Oligopeptídeos/síntese química , Oligopeptídeos/química , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Relação Estrutura-Atividade
19.
Chem Pharm Bull (Tokyo) ; 67(2): 155-158, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30713276

RESUMO

Aminopeptidase N, also known as CD13, is a transmembrance protease with many functions. CD13 is involved in inflammatory diseases and cancers. A convenient and reliable laboratory test method for detecting the suppressing effects of enzyme activity would be useful for study of CD13 inhibitors. Porcine CD13 (pCD13) was traditionally considered an enzyme source but has significant practical disadvantages. pCD13 is not a human source, and the accuracy and reliability of experimental results are greatly reduced. In this study, a modified detection method with K562-CD13 monoclonal cells, a human-derived cell line, was established to detect the suppressing effects of enzyme activity by the CD13 inhibitor. In this method, K562-CD13 monoclonal cells were used as enzyme source and L-leucine p-nitroaniline hydrochloride as substrate. Using CD13 enzyme activity analyses, we found that the ability of the catalytic substrate was weaker in K562 cells than in the other cell lines, and K562-CD13 cells expressed significantly higher levels of CD13 enzyme activity than parental K562 cells. The enzyme activity of CD13 was detected with the new method after ubenimex treatment. The enzyme activity was significantly inhibited by ubenimex in a dose-dependent manner. In summary, this study proposes a sensitive, stable, and objective laboratory method for detecting the inhibitory effect of the CD13 inhibitor.


Assuntos
Bioensaio , Antígenos CD13/antagonistas & inibidores , Inibidores de Proteases , Animais , Humanos , Células K562 , Leucina/análogos & derivados , Leucina/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Suínos
20.
Biochem J ; 476(3): 499-512, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30622151

RESUMO

Cathepsin K (CatK) is a cysteine protease and drug target for skeletal disorders that is known for its potent collagenase and elastase activity. The formation of oligomeric complexes of CatK in the presence of glycosaminoglycans has been associated with its collagenase activity. Inhibitors that disrupt these complexes can selectively block the collagenase activity without interfering with the other regulatory proteolytic activities of the enzyme. Here, we have developed a fluorescence polarization (FP) assay to screen 4761 compounds for substrate-specific ectosteric collagenase inhibitors of CatK. A total of 38 compounds were identified that block the collagenase activity without interfering with the hydrolysis of active site substrates such as the synthetic peptide substrate, benzyloxycarbonyl-Phe-Arg-7-amido-4-methylcoumarin, and gelatin. The identified inhibitors can be divided into two main classes, negatively charged and polyaromatic compounds which suggest the binding to different ectosteric sites. Two of the inhibitors were highly effective in preventing the bone-resorption activity of CatK in osteoclasts. Interestingly, some of the ectosteric inhibitors were capable of differentiating between the collagenase and elastase activity of CatK depending on the ectosteric site utilized by the compound. Owing to their substrate-specific selectivity, ectosteric inhibitors represent a viable alternative to side effect-prone active site-directed inhibitors.


Assuntos
Catepsina K/antagonistas & inibidores , Peptídeos/química , Inibidores de Proteases/química , Animais , Catepsina K/química , Catepsina K/metabolismo , Bovinos , Humanos , Osteoclastos/enzimologia , Especificidade por Substrato
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