Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 858
Filtrar
1.
Viruses ; 13(2)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669276

RESUMO

Background: Coronavirus disease 19 (COVID-19) can develop into a severe respiratory syndrome that results in up to 40% mortality. Acute lung inflammatory edema is a major pathological finding in autopsies explaining O2 diffusion failure and hypoxemia. Only dexamethasone has been shown to reduce mortality in severe cases, further supporting a role for inflammation in disease severity. SARS-CoV-2 enters cells employing angiotensin-converting enzyme 2 (ACE2) as a receptor, which is highly expressed in lung alveolar cells. ACE2 is one of the components of the cellular machinery that inactivates the potent inflammatory agent bradykinin, and SARS-CoV-2 infection could interfere with the catalytic activity of ACE2, leading to the accumulation of bradykinin. Methods: In this case control study, we tested two pharmacological inhibitors of the kinin-kallikrein system that are currently approved for the treatment of hereditary angioedema, icatibant, and inhibitor of C1 esterase/kallikrein, in a group of 30 patients with severe COVID-19. Results: Neither icatibant nor inhibitor of C1 esterase/kallikrein resulted in changes in time to clinical improvement. However, both compounds were safe and promoted the significant improvement of lung computed tomography scores and increased blood eosinophils, which are indicators of disease recovery. Conclusions: In this small cohort, we found evidence for safety and a beneficial role of pharmacological inhibition of the kinin-kallikrein system in two markers that indicate improved disease recovery.


Assuntos
Bradicinina/análogos & derivados , Proteína Inibidora do Complemento C1/uso terapêutico , Sistema Calicreína-Cinina/efeitos dos fármacos , Calicreínas/antagonistas & inibidores , Adulto , Idoso , Bradicinina/uso terapêutico , Estudos de Casos e Controles , Reposicionamento de Medicamentos , Feminino , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade
2.
Trials ; 22(1): 71, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472675

RESUMO

BACKGROUND: SARS-CoV-2, the virus that causes COVID-19, enters the cells through a mechanism dependent on its binding to angiotensin-converting enzyme 2 (ACE2), a protein highly expressed in the lungs. The putative viral-induced inhibition of ACE2 could result in the defective degradation of bradykinin, a potent inflammatory substance. We hypothesize that increased bradykinin in the lungs is an important mechanism driving the development of pneumonia and respiratory failure in COVID-19. METHODS: This is a phase II, single-center, three-armed parallel-group, open-label, active control superiority randomized clinical trial. One hundred eighty eligible patients will be randomly assigned in a 1:1:1 ratio to receive either the inhibitor of C1e/kallikrein 20 U/kg intravenously on day 1 and day 4 plus standard care; or icatibant 30 mg subcutaneously, three doses/day for 4 days plus standard care; or standard care alone, as recommended in the clinical trials published to date, which includes supplemental oxygen, non-invasive and invasive ventilation, antibiotic agents, anti-inflammatory agents, prophylactic antithrombotic therapy, vasopressor support, and renal replacement therapy. DISCUSSION: Accumulation of bradykinin in the lungs is a common side effect of ACE inhibitors leading to cough. In animal models, the inactivation of ACE2 leads to severe acute pneumonitis in response to lipopolysaccharide (LPS), and the inhibition of bradykinin almost completely restores the lung structure. We believe that inhibition of bradykinin in severe COVID-19 patients could reduce the lung inflammatory response, impacting positively on the severity of disease and mortality rates. TRIAL REGISTRATION: Brazilian Clinical Trials Registry Universal Trial Number (UTN) U1111-1250-1843. Registered on May/5/2020.


Assuntos
Bradicinina/análogos & derivados , Proteína Inibidora do Complemento C1/administração & dosagem , Insuficiência Respiratória/tratamento farmacológico , Adulto , Bradicinina/administração & dosagem , Bradicinina/efeitos adversos , Bradicinina/antagonistas & inibidores , Bradicinina/imunologia , Bradicinina/metabolismo , Antagonistas de Receptor B2 da Bradicinina/administração & dosagem , Antagonistas de Receptor B2 da Bradicinina/efeitos adversos , Brasil , /imunologia , Ensaios Clínicos Fase II como Assunto , Proteína Inibidora do Complemento C1/efeitos adversos , Esquema de Medicação , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Calicreínas/antagonistas & inibidores , Calicreínas/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Respiratória/imunologia , Insuficiência Respiratória/virologia , /patogenicidade , Índice de Gravidade de Doença , Resultado do Tratamento
3.
Front Immunol ; 11: 2072, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922409

RESUMO

A dysregulated immune response with hyperinflammation is observed in patients with severe coronavirus disease 2019 (COVID-19). The aim of the present study was to assess the safety and potential benefits of human recombinant C1 esterase inhibitor (conestat alfa), a complement, contact activation and kallikrein-kinin system regulator, in severe COVID-19. Patients with evidence of progressive disease after 24 h including an oxygen saturation <93% at rest in ambient air were included at the University Hospital Basel, Switzerland in April 2020. Conestat alfa was administered by intravenous injections of 8400 IU followed by 3 additional doses of 4200 IU in 12-h intervals. Five patients (age range, 53-85 years; one woman) with severe COVID-19 pneumonia (11-39% lung involvement on computed tomography scan of the chest) were treated a median of 1 day (range 1-7 days) after admission. Treatment was well-tolerated. Immediate defervescence occurred, and inflammatory markers and oxygen supplementation decreased or stabilized in 4 patients (e.g., median C-reactive protein 203 (range 31-235) mg/L before vs. 32 (12-72) mg/L on day 5). Only one patient required mechanical ventilation. All patients recovered. C1INH concentrations were elevated before conestat alfa treatment. Levels of complement activation products declined after treatment. Viral loads in nasopharyngeal swabs declined in 4 patients. In this uncontrolled case series, targeting multiple inflammatory cascades by conestat alfa was safe and associated with clinical improvements in the majority of severe COVID-19 patients. Controlled clinical trials are needed to assess its safety and efficacy in preventing disease progression.


Assuntos
Betacoronavirus/efeitos dos fármacos , Proteína Inibidora do Complemento C1/uso terapêutico , Complemento C1/antagonistas & inibidores , Infecções por Coronavirus/tratamento farmacológico , Síndrome da Liberação de Citocina/tratamento farmacológico , Sistema Calicreína-Cinina/efeitos dos fármacos , Pneumonia Viral/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Proteína Inibidora do Complemento C1/análise , Fator XIa/antagonistas & inibidores , Feminino , Humanos , Calicreínas/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Pandemias , Proteínas Recombinantes/uso terapêutico , Carga Viral/efeitos dos fármacos
4.
J Med Chem ; 63(11): 5723-5733, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32374603

RESUMO

The serine protease kallikrein-related peptidase 7 (KLK7) is a member of the human tissue kallikreins. Its dysregulation leads to pathophysiological inflammatory processes in the skin. Furthermore, it plays a role in several types of cancer. For the treatment of KLK7-associated diseases, coumarinic esters have been developed as small-molecule enzyme inhibitors. To characterize the inhibition mode of these inhibitors, we analyzed structures of the inhibited protease by X-ray crystallography. Electron density shows the inhibitors covalently attached to His57 of the catalytic triad. This confirms the irreversible character of the inhibition process. Upon inhibitor binding, His57 undergoes an outward rotation; thus, the catalytic triad of the protease is disrupted. Besides, the halophenyl moiety of the inhibitor was absent in the final enzyme-inhibitor complex due to the hydrolysis of the ester linkage. With these results, we analyze the structural basis of KLK7 inhibition by the covalent attachment of aromatic coumarinic esters.


Assuntos
Cumarínicos/química , Calicreínas/antagonistas & inibidores , Inibidores de Proteases/química , Sítios de Ligação , Domínio Catalítico , Cumarínicos/metabolismo , Cristalografia por Raios X , Ésteres/química , Humanos , Calicreínas/genética , Calicreínas/metabolismo , Simulação de Dinâmica Molecular , Inibidores de Proteases/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Espectrometria de Massas em Tandem
5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(2): 219-224, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32329272

RESUMO

Prostate cancer is the most common tumor of the urinary system, and its mortality rate is second only to lung cancer. With the specific and high expression on the surface of prostate cancer cells, prostate-specific membrane antigen (PSMA) has been an ideal theranostic target of prostate cancer with great clinical significance and research value. Positron emission tomography/computed tomography (PET/CT), a new modality of molecular imaging combining functional metabolic information and anatomical structure, provides high diagnostic performance for cancer detection. This paper mainly reviewed recent progress of PSMA inhibitors labeled by positron-emitting radionuclides for early diagnosis, preoperative staging, response assessment, restaging and metastasis detection of prostate cancer.


Assuntos
Calicreínas/antagonistas & inibidores , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Antígeno Prostático Específico/antagonistas & inibidores , Neoplasias da Próstata/diagnóstico por imagem , Radioisótopos/química , Elétrons , Humanos , Masculino
6.
Exp Neurol ; 324: 113115, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31734318

RESUMO

We recently identified excessive cerebral kallikrein-8 (KLK8) mRNA and protein levels at incipient stages of Alzheimer's disease (AD) in AD patients and TgCRND8 mice. Additionally, we showed that antibody-mediated KLK8 inhibition exerts therapeutic effects on AD along with enhancing neuroplasticity, resulting in improved spatial memory in mice. Mounting evidence further substantiates an important role of the protease KLK8 in neuroplasticity. In the present study we sought to gain new mechanistic insights in the interplay between KLK8, neuroplasticity and tau phosphorylation in the context of AD. We here demonstrate that KLK8 inhibition increased the number of hippocampal Ki-67 and doublecortin positive, proliferative neuronal progenitor cells in transgenic mice, whereas the same action in wildtypes had no effect. In line with these results, KLK8 inhibition reduced the levels of its pro-proliferative interaction partners KLK6 and protease-activated receptor 2 only in wildtypes, while the levels of its proliferation-supporting substrate neuregulin-1 and the non-complexed form of its complexing-partner phosphatidylethanolamine binding protein 1 were enhanced in both genotypes. Concomitant incubation of beta-amyloid (Aß)-producing primary neurons with KLK8 and its inhibitory antibody increased neurite complexity and soma size. KLK8 inhibition in SH-SY5Y cells or in primary neurons increased levels of the neuroplasticity-supporting KLK8 substrate ephrin receptor B2 (EPHB2) and total tau while decreasing the relative amount of phospho-tau in relation to total tau. KLK8 blockade further enhanced cell proliferation in SH-SY5Y cells. Additional co-incubation with an inhibitory anti-EPHB2 antibody decreased total tau levels and neurite complexity and increased the ratio of phospho-tau/total tau, underlining the key role of EPHB2 on this plastic change. In a reverse in vitro approach, KLK8 induction reduced EPHB2 and total tau and increased the ratio of phospho-tau/total tau, leading to impaired proliferation and neuronal differentiation. These results underline the therapeutic potential of KLK8 inhibition by counteracting plasticity deficits in AD-affected brain.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Calicreínas/antagonistas & inibidores , Plasticidade Neuronal/efeitos dos fármacos , Doença de Alzheimer/psicologia , Animais , Anticorpos Bloqueadores/administração & dosagem , Anticorpos Bloqueadores/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Injeções Intraventriculares , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Neurônios/efeitos dos fármacos , Fosforilação , Receptor EphB2/antagonistas & inibidores , Receptor EphB2/imunologia , Receptor EphB2/metabolismo , Memória Espacial , Proteínas tau/metabolismo
7.
Curr Radiopharm ; 13(1): 63-79, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31362683

RESUMO

BACKGROUND: The rising incidence rate of prostate cancer (PCa) has promoted the development of new diagnostic and therapeutic radiopharmaceuticals during the last decades. Promising improvements have been achieved in clinical practice using prostate specific membrane antigen (PSMA) labeled agents, including specific antibodies and small molecular weight inhibitors. Focusing on molecular docking studies, this review aims to highlight the progress in the design of PSMA targeted agents for a potential use in nuclear medicine. RESULTS: Although the first development of radiopharmaceuticals able to specifically recognize PSMA was exclusively oriented to macromolecule protein structure such as radiolabeled monoclonal antibodies and derivatives, the isolation of the crystal structure of PSMA served as the trigger for the synthesis and the further evaluation of a variety of low molecular weight inhibitors. Among the nuclear imaging probes and radiotherapeutics that have been developed and tested till today, labeled Glutamate-ureido inhibitors are the most prevalent PSMA-targeting agents for nuclear medicine applications. CONCLUSION: PSMA represents for researchers the most attractive target for the detection and treatment of patients affected by PCa using nuclear medicine modalities. [99mTc]MIP-1404 is considered the tracer of choice for SPECT imaging and [68Ga]PSMA-11 is the leading diagnostic for PET imaging by general consensus. [18F]DCFPyL and [18F]PSMA-1007 are clearly the emerging PET PSMA candidates for their great potential for a widespread commercial distribution. After paving the way with new imaging tools, academic and industrial R&Ds are now focusing on the development of PSMA inhibitors labeled with alpha or beta minus emitters for a theragnostic application.


Assuntos
Calicreínas/antagonistas & inibidores , Antígeno Prostático Específico/antagonistas & inibidores , Neoplasias da Próstata/tratamento farmacológico , Amidas/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Desenvolvimento de Medicamentos , Descoberta de Drogas , Glutamatos/uso terapêutico , Humanos , Fragmentos de Imunoglobulinas/uso terapêutico , Masculino , Medicina Nuclear , Organofosfonatos/uso terapêutico , Ácidos Fosfóricos/uso terapêutico , Compostos Radiofarmacêuticos , Compostos de Sulfidrila/uso terapêutico , Ureia/análogos & derivados , Ureia/uso terapêutico
8.
Expert Rev Clin Immunol ; 15(12): 1239-1248, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31721602

RESUMO

Introduction: Hereditary angioedema (HAE) with C1 esterase inhibitor deficiency (C1-INH-HAE) is a rare disease that manifests with cutaneous and/or submucosal swellings due to uncontrolled activation of the contact/kinin system. Attacks recur with unpredictable frequency and severity, laryngeal edema is potentially lethal, and the disease burden may severely disrupt patients' lives.Areas covered: This review provides an overview of lanadelumab, a human monoclonal antibody targeted against plasma kallikrein that was recently approved for prevention of symptoms in C1-INH-HAE.Expert opinion: The phase III HELP Study demonstrated the efficacy of lanadelumab in reducing HAE attacks. These positive results are being further confirmed in the open-label extension study. This agent addresses some of the limitations of existing prophylactic options as tolerability issues, the need for intravenous administration and frequent dosing. Therefore, lanadelumab can profoundly improve the quality of life of patients with C1-INH-HAE.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Administração Intravenosa , Humanos , Calicreínas/antagonistas & inibidores , Qualidade de Vida
9.
Immunotherapy ; 11(17): 1439-1444, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31635497

RESUMO

Hereditary angioedema (HAE) is rare disorder caused by a SERPING1 gene mutation that triggers severe swelling of the skin and upper airway. Treatment options for HAE with deficient and dysfunctional C1-inhibitor are expanding to include small-molecule drugs that inhibit protein interactions in the kallikrein-kinin system. Discovered by BioCryst Pharmaceuticals, BCX7353 is a synthetic, once-daily, small molecule drug that can be taken as an oral capsule to treat HAE attacks and for prophylaxis. This article will summarize recent and current BCX7353 clinical trials. Overall, results indicate BCX7353 is a promising form of therapy with a rapid 1 h onset of action, long duration of action, and acceptable tolerance.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Calicreínas/antagonistas & inibidores , Pirazóis/administração & dosagem , Administração Oral , Angioedemas Hereditários/prevenção & controle , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Bioorg Med Chem Lett ; 29(20): 126675, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521475

RESUMO

The connection between Netherton syndrome and overactivation of epidermal/dermal proteases, particularly Kallikrein 5 (KLK5) has been well established and it is expected that a KLK5 inhibitor would improve the dermal barrier and also reduce the pain and itch that afflict Netherton syndrome patients. One of the challenges of covalent protease inhibitors has been achieving selectivity over closely related targets. In this paper we describe the use of structural insight to design and develop a selective and highly potent reversibly covalent KLK5 inhibitor from an initial weakly binding fragment.


Assuntos
Benzamidinas/química , Calicreínas/antagonistas & inibidores , Síndrome de Netherton/tratamento farmacológico , Inibidores de Serino Proteinase/química , Sequência de Aminoácidos , Benzamidinas/farmacologia , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Humanos , Isomerismo , Modelos Moleculares , Estrutura Molecular , Mutação , Ligação Proteica , Inibidor de Serinopeptidase do Tipo Kazal 5/genética , Inibidores de Serino Proteinase/farmacologia , Relação Estrutura-Atividade
11.
Immunotherapy ; 11(11): 937-944, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31234673

RESUMO

Hereditary angioedema with C1 esterase inhibitor deficiency is a rare disorder characterized by unpredictable swelling of the face, larynx and gastrointestinal tract. Kallikreins are serine proteases that cleave kininogens to produce bradykinin leading to inflammation. A new prophylactic drug is lanadelumab (DX-2930, SHP-643), a recombinant, fully human IgG1 monoclonal antibody kallikrein inhibitor. Pharmacokinetics show a half-life of 14 days with a dose-dependent effect. Completed trials for lanadelumab include two Phase III studies with updated efficacy in preventing angioedema in hereditary angioedema patients. Ongoing data show the safety of the targeted therapy along with less frequent administration requirements. Information on long-term safety is still needed, as well as, further studies on the correlation of subcutaneous administered dosing requirements and severity of side effects.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Calicreínas/antagonistas & inibidores , Angioedemas Hereditários/metabolismo , Angioedemas Hereditários/patologia , Bradicinina/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Calicreínas/metabolismo
12.
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
13.
Prostate Cancer Prostatic Dis ; 22(4): 624-632, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31043681

RESUMO

BACKGROUND: The fibroblast growth factor receptor (FGFR) signaling pathway is activated in multiple tumor types through gene amplifications, single base substitutions, or gene fusions. Multiple small molecule kinase inhibitors targeting FGFR are currently being evaluated in clinical trials for patients with FGFR chromosomal translocations. Patients with novel gene fusions involving FGFR may represent candidates for kinase inhibitors. METHODS: A targeted RNA-sequencing assay identified a KLK2-FGFR2 fusion gene in two patients with metastatic prostate cancer. NIH3T3 cells were transduced to express the KLK2-FGFR2 fusion. Migration assays, Western blots, and drug sensitivity assays were performed to functionally characterize the fusion. RESULTS: Expression of the KLK2-FGFR2 fusion protein in NIH3T3 cells induced a profound morphological change promoting enhanced migration and activation of downstream proteins in FGFR signaling pathways. The KLK2-FGFR2 fusion protein was determined to be highly sensitive to the selective FGFR inhibitors AZD-4547, BGJ398, JNJ-42756943, the irreversible inhibitor TAS-120, and the non-selective inhibitor Ponatinib. The KLK2-FGFR2 fusion did not exhibit sensitivity to the non-selective inhibitor Dovitinib. CONCLUSIONS: Importantly, the KLK2-FGFR2 fusion represents a novel target for precision therapies and should be screened for in men with prostate cancer.


Assuntos
Calicreínas/genética , Proteínas de Fusão Oncogênica/genética , Neoplasias da Próstata/genética , Inibidores de Proteínas Quinases/uso terapêutico , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Animais , Carcinogênese/genética , Movimento Celular/genética , Células HEK293 , Humanos , Calicreínas/antagonistas & inibidores , Calicreínas/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Terapia de Alvo Molecular/métodos , Células NIH 3T3 , Medicina de Precisão/métodos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de RNA , Transfecção
14.
Clin Chem Lab Med ; 57(11): 1737-1743, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31129650

RESUMO

Background Aberrant kallikrein activity is observed in a number of inflammatory dermatoses. Up-regulation of kallikrein-5 (KLK5) activity leads to uncontrolled skin desquamation and cleavage of proteinase-activated receptor-2 (PAR2), causing the release of pro-inflammatory cytokines and disruption of epidermal barrier function. This study aimed to identify KLK5-specific small molecule inhibitors which can serve as the foundation of a novel therapeutic for inflammatory skin disorders. Methods Five chemical libraries (13,569 compounds total) were screened against recombinant KLK5 using a fluorogenic enzymatic assay. Secondary validation was performed on the top 22 primary hits. All hits were docked in the KLK5 crystal structure to rationalize their potential interactions with the protein. Results A naturally occurring compound derived from the wood of Caesalpinia sappan (Brazilin) was identified as a novel KLK5 inhibitor (IC50: 20 µM, Ki: 6.4 µM). Docking suggests that the phenolic moiety of Brazilin binds in the S1-pocket of KLK5 and forms a H-bond with S195 side chain. KLK14 was also found to be susceptible to inhibition by Brazilin with a calculated IC50 value of 14.6 µM. Conclusions Natural KLK5 small molecule inhibitors such as Brazilin, are ideal for topical skin disease drug design and remain a promising therapeutic for severe cases of inflammatory skin disorders. Optimized KLK inhibitors may have increased efficacy as therapeutics and warrant further investigation.


Assuntos
Benzopiranos/uso terapêutico , Calicreínas/antagonistas & inibidores , Dermatopatias/tratamento farmacológico , Benzopiranos/farmacologia , Humanos
15.
Biochemistry ; 58(21): 2524-2533, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31058493

RESUMO

Sunflower trypsin inhibitor (SFTI-1) is a 14 amino acid serine protease inhibitor. The dual antiparallel ß-sheet arrangement of SFTI-1 is stabilized by an N-terminal-C-terminal backbone cyclization and a further disulfide bridge to form a final bicyclic structure. This constrained structure is further rigidified by an extensive network of internal hydrogen bonds. Thus, the structure of SFTI-1 in solution resembles the protease-bound structure, reducing the entropic penalty upon protease binding. When cleaved at the scissile bond, it is thought that the rigidifying features of SFTI-1 maintain its structure, allowing the scissile bond to be reformed. The lack of structural plasticity for SFTI-1 is proposed to favor initial protease binding and continued occupancy in the protease active site, resulting in an equilibrium between the cleaved and uncleaved inhibitor in the presence of a protease. We have determined, at 1.15 Å resolution, the X-ray crystal structures of complexes between human kallikrein-related peptidase 4 (KLK4) and SFTI-FCQR(Asn14) and between KLK4 and an acyclic form of the same inhibitor, SFTI-FCQR(Asn14)[1,14], with the latter displaying a cleaved scissile bond. Structural analysis and MD simulations together reveal the roles of the altered contact sequence, intramolecular hydrogen bonding network, and backbone cyclization in altering the state of SFTI's scissile bond ligation at the protease active site. Taken together, the data presented reveal insights into the role of dynamics in the standard-mechanism inhibition and suggest that modifications on the non-contact strand may be a useful, underexplored approach for generating further potent or selective SFTI-based inhibitors against members of the serine protease family.


Assuntos
Calicreínas/química , Peptídeos Cíclicos/química , Proteínas de Plantas/química , Inibidores de Serino Proteinase/química , Animais , Domínio Catalítico , Cristalografia por Raios X , Ciclização , Escherichia coli/metabolismo , Humanos , Ligação de Hidrogênio , Calicreínas/antagonistas & inibidores , Calicreínas/metabolismo , Modelos Moleculares , Simulação de Dinâmica Molecular , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia , Proteínas de Plantas/farmacologia , Ligação Proteica , Conformação Proteica em Folha beta , Inibidores de Serino Proteinase/farmacologia , Spodoptera/citologia , Spodoptera/metabolismo , Transfecção
16.
J Comput Aided Mol Des ; 33(5): 461-475, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30989572

RESUMO

Kallikrein-8, a serine protease, is a target for structure-based drug design due to its therapeutic potential in treating Alzheimer's disease and is also useful as a biomarker in ovarian cancer. We present a binding assessment of ligands to kallikrein-8 using a residue-wise decomposition of the binding energy. Binding of four putative inhibitors of kallikrein-8 is investigated through molecular dynamics simulation and ligand binding energy evaluation with two methods (MM/PBSA and WaterSwap). For visualization of the residue-wise decomposition of binding energies, chemical energy-wise decomposition or CHEWD is introduced as a plugin to UCSF Chimera and Pymol. CHEWD allows easy comparison between ligands using individual residue contributions to the binding energy. Molecular dynamics simulations indicate one ligand binds stably to the kallikrein-8 S1 binding site. Comparison with other members of the kallikrein family shows that residues responsible for binding are specific to kallikrein-8. Thus, ZINC02927490 is a promising lead for development of novel kallikrein-8 inhibitors.


Assuntos
Calicreínas/antagonistas & inibidores , Sítios de Ligação , Desenho de Fármacos , Descoberta de Drogas , Humanos , Calicreínas/química , Calicreínas/metabolismo , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Software , Termodinâmica
17.
J Thromb Thrombolysis ; 47(4): 533-539, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30955141

RESUMO

Lizards in the genus Heloderma are the most ancient venomous reptiles, with a traceable lineage nearly 100 million years old. The proteome of the venom of three of the remaining species (Heloderma suspectum, H. exasperatum, H. horridum) are very conserved, with kallikrein-like activity present to cause critical hypotension to immobilize and outright kill prey. Kallikrein-like activity would be expected to activate the contact protein pathway of coagulation, which would be detectable with thrombelastography in human plasma. Thus, it was proposed to determine if kallikrein-like activity could be detected with thrombelastography, and if this activity could be inhibited by carbon monoxide (CO) via a putative heme-based mechanism. Procoagulant activity of each venom was assessed via thrombelastography with normal plasma, and kallikrein-like activity confirmed with FX-depleted plasma. Venom was then exposed to carbon monoxide releasing molecule-2 (CORM-2) or its inactive releasing molecule to assess CO inhibition. All three venoms demonstrated kallikrein-like activity with the same potency and inhibition of activity by CO. In conclusion, the present work documented that procoagulant, kallikrein-like activity containing venoms of the oldest species of venomous reptiles was inhibited by CO, potentially via heme modulation. This is also the first identification and characterization of a kallikrein-like enzyme utilizing coagulation factor-depleted plasma to assess venom that inflicts hypotension. Future investigations will continue to define the vulnerability of venom enzymatic activities to CO.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Monóxido de Carbono/química , Calicreínas , Lagartos , Proteínas de Répteis , Peçonhas , Animais , Humanos , Calicreínas/antagonistas & inibidores , Calicreínas/química , Calicreínas/farmacologia , Proteínas de Répteis/antagonistas & inibidores , Proteínas de Répteis/química , Proteínas de Répteis/farmacologia , Tromboelastografia , Peçonhas/química , Peçonhas/farmacologia
18.
Bioorg Med Chem Lett ; 29(12): 1454-1458, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31005442

RESUMO

The connection between Netherton syndrome and overactivation of epidermal/dermal proteases particularly KLK5 has been well established. To treat sufferers of this severe condition we wished to develop a topical KLK5 inhibitor in order to normalise epidermal shedding and reduce the associated inflammation and itching. In this paper we describe structure-based optimisation of a series of brightly coloured weak KLK5 inhibitors into colourless, non-irritant molecules with good KLK5 activity and selectivity over a range of serine proteases.


Assuntos
Desenho de Fármacos , Calicreínas/antagonistas & inibidores , Síndrome de Netherton/tratamento farmacológico , Humanos
19.
Bioorg Med Chem Lett ; 29(9): 1094-1098, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30833107

RESUMO

Human kallikreins 5 and 7 (KLK5 and KLK7) exhibit trypsin- and chymotrypsin-like activities and are involved in pathologies related to skin desquamation process. A series of new 3-acyltetramic acids were developed as a novel class of inhibitors of KLK5, KLK7 and trypsin enzymes. The nature and length of the acyl chain is crucial to the KLK5, KLK7 and trypsin inhibition activities, and the most potent compounds (but not the most selective) 2b, 2c and 2g showed low micromolar IC50 values. While very few of the compounds were selective for KLK5, the selective inhibition of trypsin against chymotrypsin was achieved. Our molecular modelling studies revealed that the double bond in 2g provided the best fit in the binding site of KLK5, while the hydrogen bonding interactions modulated the best fit of 2c in the binding site of KLK7 due to the hydrophobicity of the cavity.


Assuntos
Calicreínas/antagonistas & inibidores , Pirrolidinonas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Calicreínas/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , Relação Estrutura-Atividade
20.
Expert Opin Biol Ther ; 19(6): 517-526, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30912460

RESUMO

INTRODUCTION: Hereditary angioedema due to C1-INH deficiency (C1-INH-HAE) is a rare disease with unpredictable, self-limiting and localized swelling episodes involving the cutaneous and subcutaneous tissues. In the last decade, the spectrum of the possibilities to control the disease has considerably changed with the development of biologic therapies making necessary a careful evaluation of the differences among current and emerging treatments to properly optimize the management of patients. AREAS COVERED: This review serves to summarize the literature regarding the use of biologics for the treatment of C1-INH-HAE. Medications already available on the market and new drugs in different phases of development are addressed. EXPERT OPINION: The advent of biologic therapies dramatically improved the lives of patients with C1-INH-HAE although further improvement is still needed. Whether this is cost/effective will be answered in the next years when we will see if these major advances will benefit the majority of the patients.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Angioedemas Hereditários/genética , Anticorpos Monoclonais/uso terapêutico , Antagonistas de Receptor B2 da Bradicinina/uso terapêutico , Proteína Inibidora do Complemento C1/metabolismo , Proteína Inibidora do Complemento C1/uso terapêutico , Fator XII/imunologia , Terapia Genética , Humanos , Calicreínas/antagonistas & inibidores , Calicreínas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/uso terapêutico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...