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3.
Heliyon ; 10(10): e30969, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813202

RESUMO

Snake venoms, comprising a complex array of protein-rich components, an important part of which are snake venom metalloproteinases (SVMPs). These SVMPs, which are predominantly isolated from viperid venoms, are integral to the pathology of snakebites. However, SVMPs derived from elapid venoms have not been extensively explored, and only a handful of SVMPs have been characterized to date. Atrase A, a nonhemorrhagic P-III class metalloproteinase from Naja atra venom, exhibits weak proteolytic activity against fibrinogen in vitro but has pronounced anticoagulant effects in vivo. This contrast spurred investigations into its anticoagulant mechanisms. Research findings indicate that atrase A notably extends the activated partial thromboplastin time, diminishes fibrinogen levels, and impedes platelet aggregation. The anticoagulant action of atrase A primarily involves inhibiting coagulation factor VIII and activating the endogenous fibrinolytic system, which in turn lowers fibrinogen levels. Additionally, its effect on platelet aggregation further contributes to its anticoagulant profile. This study unveils a novel anticoagulant mechanism of atrase A, significantly enriching the understanding of the roles of cobra venom metalloproteinases in snake venom. Furthermore, these findings underscore the potential of atrase A as a novel anticoagulant drug, offering insights into the functional evolutions of cobra venom metalloproteinases.

5.
Front Immunol ; 14: 1275254, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37876928

RESUMO

Background: Immune checkpoint inhibitors (ICIs) therapy can be complicated by their potential cardiovascular toxicities, including myocarditis. Nowadays, no prospective trials have focused on ICI-associated myocarditis optimized management. Available evidence only come from case reports or series. A systematic case reports analysis was conducted to collect and evaluate emerging evidence of ICI-associated myocarditis to provide more information to clinicians. Methods: We performed a literature search for eligible case reports or series published between January 2018 and May 2023 using the PubMed database. Then, we extracted interesting information via table form. Finally, this study included 113 publications on 106 patients with ICI-associated myocarditis. Results: Myocarditis was found to be a highly life-threatening disease, with 53.8% of cases. Over half of cases were life-threatening (G4, 23.6%) or severe (G3, 35.8%) and required glucocorticoids. Higher rates of improvement were associated with the best response to ICI for complete response/partial response (72.7% vs. 53.9%), glucocorticoid administration (30% vs. 22%), and discontinuation of ICI (58.8% vs. 32.1%). Consequently, ICI-associated G3-G4 myocarditis should be treated with a combination of discontinuation of ICIs, high-dose glucocorticoids, other drugs, chemical drugs, plasma exchange, and life support. For moderate G1 or G2 cases, discontinuation of ICIs and regular-dose glucocorticoids should be considered. Conclusion: Once full recovery or improvement was achieved; glucocorticoids can be administered at low doses or stopped. Notably, re-challenge with ICIs appears feasible after resolution or meaningful improvement of myocarditis.


Assuntos
Inibidores de Checkpoint Imunológico , Miocardite , Humanos , Glucocorticoides , Coração , Inibidores de Checkpoint Imunológico/efeitos adversos , Miocardite/induzido quimicamente , Miocardite/diagnóstico
6.
Drug Discov Today ; 28(2): 103436, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36370993

RESUMO

Natural killer (NK) cell therapy is emerging as a cancer treatment. NK cells are innate cytotoxic lymphocytes that act as first-line responders to kill target cells without prior encounters. NK cells recognize cancer cells, virus-infected cells, and other types of stressed cell through a reservoir of germline-encoded receptors. NK cells are safe for allogeneic applications. Therefore, they are the ideal off-the-shelf cell, which overcome the low efficiency issue caused by the patient-by-patient nature of autologous cell therapy. Unlike T cells, NK cells cannot form a strong immune memory; therefore, they suffer from short in vivo persistence. However, different from T cells, NK cells have a reservoir of innate immune receptors targeting a variety of malignant cells. In addition, they can utilize antibody guidance in target recognition. With suitable engineering, NK cells can function as universal anticancer drugs that are not restricted to HLA and cancer types, which will benefit the large cohort of patients with rare cancer types and patients with no convenient drug targets for precision and personalized medicine. Here, we summarize and discuss the designs of current anticancer NK cell therapies.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Células Matadoras Naturais , Neoplasias/tratamento farmacológico , Linfócitos T , Imunoterapia Adotiva , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/metabolismo , Desenvolvimento de Medicamentos
7.
Cell Death Dis ; 13(2): 130, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136014

RESUMO

Although there are many studies on the relationship between genetic polymorphisms and the incidence of diseases, mechanisms are rarely known. We report the mechanism by which signal transducer and activator of transcription 4 (stat4) rs7574865 promotes the occurrence and progression of hepatocellular carcinoma (HCC). We found that the GG genotype at stat4 rs7574865 was a risk genotype, and STAT4 levels in serum and peritumoral tissue from HCC patients with the GG genotype were significantly higher than those found in TT or TG carriers. Furthermore, HCC patients with the GG genotype or elevated STAT4 levels had poor prognoses. In vitro experiments demonstrated that STAT4 silencing promoted apoptosis and inhibited the invasion and migration of HepG2 and L02 cells. Proteomic analysis of HCC peritumors identified 273 proteins related to STAT4, of which CYP2E1 activity and FGL2 content exhibited the highest positive correlation. The relationship between CYP2E1 and FGL2 was also confirmed in cyp2e1-/- mice and in CYP2E1 inhibitor-treated mice. In conclusion, this study elucidates the mechanism by which the stat4 rs7574865 polymorphism promotes the occurrence and progression of HCC via the Stat4/CYP2E1/FGL2 pathway.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Fator de Transcrição STAT4 , Animais , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/genética , Estudos de Casos e Controles , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Fibrinogênio/metabolismo , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Camundongos , Polimorfismo de Nucleotídeo Único , Proteômica , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 255: 119717, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33794423

RESUMO

The silver nanoparticles have been frequently used in SERS detection, for their unique optical properties and sensitive surface Raman enhancement properties. However, as the preparation of silver nanoparticles will use polyvinylpyrrolidone (PVP) to achieve the effect of reducing agent and surfactant, the surface of the prepared silver nanoparticles will be wrapped by PVP, forming an insulating layer and an ill-defined AgNPs interface, which limits the plasmonic coupling between the laminates of AgNPs. This paper reported a simple method to remove PVP for high performance and reusable SERS substrate, and the residue of PVP was studied after clean centrifugal by ethanol or water. When the number of cleaning times reached 10, there was basically no residual of PVP. The cleaned AgNPs interface effectively enhanced the plasma resonance of the local surface (LSPR) and greatly improved the SERS activity of the substrate. Moreover, probe molecules (R6G) are introduced to study the influence of single molecule PVP on subsequent detection. Through the competitive relationship between the two, it can be concluded that residual PVP has basically no influence on detection of the molecular which absorbed stronger than PVP, and the remaining PVP can be ignored.

9.
Toxicon ; 187: 223-231, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32971099

RESUMO

Snake venom metalloproteinases (SVMPs) are an important component in viperid and crotalid venoms, and these SVMPs play important and versatile roles in the pathogenesis of snakebite envenoming. The SVMPs from elapid venoms are not well elucidated compared with those from viperid and crotalid venoms. Atrase B is a nonhemorrhagic P-III SVMP purified from the Naja atra venom, which possesses a weak fibrinogenolytic activity. In this paper, the activity and mechanism of atrase B against platelet aggregation and blood coagulation were investigated. The in vitro assay showed that atrase B remarkably inhibited ristocetin- and thrombin-induced platelet aggregation by cleavage of the platelet membrane glycoprotein Ib, and the coagulation of normal human plasma, which may be caused by inhibiting coagulation factor VIII predominantly. When atrase B was intravenously injected into rats at doses of 0.05 and 0.30 mg/kg, the activated partial thromboplastin and the thrombin times were significantly prolonged in a dose-dependent manner. Similarly, the fibrinogen level decreased, but only a high dose of atrase B showed remarkable activity against platelet aggregation. Results suggested that anticoagulation was a more important function of atrase B compared with its activity against platelet aggregation. These results indicated that atrase B may play an important role in the anticoagulant properties of Naja atra venom. In addition, atrase B may be a potent anticoagulant agent because its effectiveness in vivo against platelet aggregation and blood coagulation.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Venenos Elapídicos/toxicidade , Metaloproteases/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Animais , Humanos , Ratos
10.
Int J Clin Pharmacol Ther ; 58(3): 177-182, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31933472

RESUMO

OBJECTIVE: The objective of this study was to evaluate and compare the pharmacokinetics of domperidone tablets in Chinese healthy subjects both under fasting and fed conditions. MATERIALS AND METHODS: A total of 36 subjects were recruited to the monocentric pharmacokinetic study. All subjects were randomly divided into two groups. One group was given a single 10-mg oral dose of domperidone tablet after ~ 10 hours of fasting, and the other group was given the same oral dose of domperidone tablet 30 minutes after a high-fat meal. 18 blood samples were collected over 24 hours for every subject. Plasma concentrations of domperidone were analyzed by a rapid and sensitive UPLC-MS/MS assay, and the pharmacokinetic parameters were determined by the standard non-compartmental method. RESULTS: A significant difference was observed in the pharmacokinetics of domperidone between fasting and fed subjects. The AUC0-24h (area under curve of plasma concentration until the last concentration observed) was 75.71 h×µg/L in the fed subjects, which was much higher than AUC0-24h (56.76 h×µg/L) in the fasting subjects. For the fasting test, the T1/2 (elimination half-life) was 7.15 hours, Cmax (the maximum plasma concentration) was 16.97 µg/L, and tmax; was 0.79 hours. For the fed test, the T1/2 was 8.72 hours, Cmax was 15.11 µg/L, and tmax was 1.66 hours. T1/2 and tmax were both prolonged under fed condition when comparing fed condition to fasting condition. CONCLUSION: In this study, the absorption and elimination of domperidone was slowed down by a high-fat meal, with the mean tmax being 52% longer and T1/2 18% longer in fed subjects than in fasting subjects. In addition, a high-fat meal increased the exposure of domperidone, with the mean AUC being 25% more in fed subjects than in fasting subjects, which provided an important reference for the clinical application of domperidone in the Chinese population.


Assuntos
Cromatografia Líquida de Alta Pressão , Domperidona/farmacocinética , Jejum , Espectrometria de Massas em Tandem , Adolescente , Adulto , Área Sob a Curva , Gorduras na Dieta/administração & dosagem , Feminino , Voluntários Saudáveis , Humanos , Masculino , Refeições , Pessoa de Meia-Idade , Comprimidos , Equivalência Terapêutica , Adulto Jovem
11.
Mol Carcinog ; 58(8): 1481-1491, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31116889

RESUMO

Cytochrome P450 2E1 (CYP2E1) is an important drug-metabolizing enzyme that has been recognized as one of the risk factors for hepatofibrosis. Macrophages play key roles in regulating hepatofibrosis progression and resolution. However, whether CYP2E1 is involved in the regulation of macrophage polarization during hepatofibrosis is still unclear. Herein, we measured CYP2E1 activity and the expression of CD163 (an M2 marker) and CD68 (a pan-macrophage marker) in hepatofibrotic tissue from HCC patients (n = 26) with comparison to normal liver tissue (n = 26). The relationship of CYP2E1 activity in vivo and the CD163/CD68 ratio (an indicator of M2 polarization), as well as the extent of hepatofibrosis, were evaluated in diethylnitrosamine (DEN)-treated Sprague-Dawley rats. Strikingly, CYP2E1 activity and expression of CD68 increased and the CD163/CD68 ratio decreased, especially in hepatofibrotic tissue with higher CYP2E1 activity. Expression of α-SMA, Ki67, and PCNA were positively correlated with CYP2E1 activity and inversely correlated with the CD163/CD68 ratio. Furthermore, CYP2E1 activity showed an inverse correlation with the CD163/CD68 ratio. Overall, high CYP2E1 activity aggravates hepatofibrosis by restraining M2 macrophage polarization, providing a novel insight for understanding the profibrotic activity of CYP2E1 and a promising avenue for hepatofibrosis therapy.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Cirrose Hepática/patologia , Macrófagos/metabolismo , Receptores de Superfície Celular/metabolismo , Actinas/metabolismo , Animais , Dietilnitrosamina/toxicidade , Humanos , Antígeno Ki-67/metabolismo , Fígado/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Masculino , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley
12.
Genes Immun ; 20(6): 484-492, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30139952

RESUMO

Emerging evidence revealed that thyroglobulin (TG) contributes to the development of autoimmune disease, and the relationship between TG and autoimmune thyroid disease (AITD) is still controversial. The aim of this study was to quantify the association between rs2076740, rs853326, rs180223, and rs2069550 TG polymorphisms and risk of AITD using a meta-analysis approach. We identified all studies that assessed the association between TG polymorphisms and AITD from PubMed, Embase, and Web of Science databases. A total of 3013 cases and 1812 controls from ten case-control studies were included. There was no significant associations found between rs2069550, rs180223, and rs853326 polymorphisms and AITD risk. The association between the rs2076740 polymorphism and AITD risk was significant in the codominant model (P = 0.005), suggesting the CC rs2076740 genotype might be a protective factor for AITD. Sensitivity analysis by removing one or two study changed the results in dominant rs2076740 and rs853326 and rs2069550 allele models (P = 0.016, 0.024, 0.027). Latitude and ethnicity significantly affected the association between rs2076740 and rs2069550 polymorphisms and AITD, indicating their protective effects in allele or dominant model (P = 0.012, 0.012, 0.012, 0.009, 0.009). The association between rs2076740, rs2069550, and rs853326 polymorphisms and AITD risk is significantly affected by study characteristics.


Assuntos
Polimorfismo de Nucleotídeo Único , Tireoglobulina/genética , Tireoidite Autoimune/genética , Alelos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Fatores de Risco , Tireoidite Autoimune/etnologia , Tireoidite Autoimune/etiologia
13.
Gene ; 664: 44-49, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29678659

RESUMO

OBJECTIVE: Cyclosporine (CsA) is a substrate of cytochrome P450 (CYP) 3A4 with a narrow therapeutic index and large individual difference. CYP3A4*1B is reported to be associated with CsA pharmacokinetics parameters, but the relevance is still in dispute. Therefore, a meta-analysis was employed to evaluate the influence of CYP3A4*1B on CsA pharmacokinetics at different post-transplantation times in adult renal transplant recipients. METHODS: Studies on evaluating the CYP3A4*1B genotype and CsA pharmacokinetics were retrieved through a systematical search of relevant database including PubMed, Emabase, Web of science, the Cochrane Library, Clinical Trials.gov and three Chinese literature databases (up to 15 October 2017). The pharmacokinetic parameters: weight-adjusted CsA daily dose (Dose), cyclosporine trough concentration (C0) and trough concentration/weight-adjusted CsA daily dose ratio (C0/Dose ratio) were extracted, and all statistical analysis were performed by using Review Manager 5.1.0. RESULTS: Four studies (involving 452 adult renal transplant recipients) were included in this meta-analysis. For the C0/Dose ratio, in all included renal transplant recipients, CYP3A4*1B carriers exhibited higher C0/Dose ratio than CYP3A4*1 (WMD 7.38, 95% CI 1.26-13.51; P = 0.02). The differences between CYP3A4*1B carriers and CYP3A4*1 in Dose (WMD 0.36, 95% CI 0.85-0.12; P = 0.14), C0 (WMD 10.81, 95% CI 77.72-99.34; P = 0.81) were not statistically significant. According to post-transplantation time, subgroup analysis also showed no significant statistical significance between CYP3A4*1B carriers and CYP3A4*1 carriers in Dose or C0. However, this result should be further explored because only four studies were included. CONCLUSIONS: CYP3A4*1B is associated with CsA C0/Dose ratio in renal transplant recipients which indicates patients with CYP3A4*1B allele require lower dose of CsA to reach target blood concentration compared with the CYP3A4*1 carriers.


Assuntos
Ciclosporina/farmacocinética , Citocromo P-450 CYP3A/genética , Rejeição de Enxerto/prevenção & controle , Imunossupressores/farmacocinética , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Alelos , Povo Asiático/genética , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Genótipo , Humanos , Imunossupressores/uso terapêutico , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único , Transplantados
14.
J Pharmacol Exp Ther ; 365(2): 398-407, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29467309

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common types of primary liver cancer and the third most frequent cause of cancer death worldwide. Diethylnitrosamine (DEN) is one of the recognized risk factors for hepatocarcinogenesis likely due to CYP2E1-mediated metabolic activation. However, CYP2E1-mediated DEN metabolic activity in non-neoplastic liver tissue from HCC patients has not been determined; the role of CYP2E1 activity, in particular CYP2E1 constitutive activity and CYP2E1 inhibited activity, with respect to the hepatocarcinogenesis induced by DEN is not yet clear. Herein, we determined CYP2E1-mediated DEN metabolic activity in non-neoplastic liver tissue from HCC patients and found that CYP2E1-mediated DEN metabolic activity was significantly elevated with a 43.3% positive rate, and clinicopathologic parameters did not affect the activity. Then, using a Sprague-Dawley rat liver tumor model induced by DEN, the relationship between CYP2E1 constitutive/inhibited activity and hepatocarcinogenesis was explored. The results showed that the CYP2E1 constitutive activity was strongly correlated with tumor incidence and severity of liver tumorigenesis (nodule numbers and size), whereas inhibition of CYP2E1 activity decreased hepatocyte proliferation, liver injury, and liver carcinogenesis in the presence of DEN. In conclusion, the higher CYP2E1 activity would lead to an increased incidence of HCC as a result of CYP2E1-mediated DEN activation. Therefore, higher CYP2E1 activity might be a risk factor for HCC induced by DEN.


Assuntos
Carcinogênese/induzido quimicamente , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Citocromo P-450 CYP2E1/metabolismo , Dietilnitrosamina/farmacologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Animais , Carcinogênese/efeitos dos fármacos , Inibidores do Citocromo P-450 CYP2E1/farmacologia , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley
15.
Artigo em Inglês | MEDLINE | ID: mdl-25277490

RESUMO

BACKGROUND AND AIM: Amniotic membrane-derived mesenchymal stem cells (hAM-dMSCs) are a potential source of mesenchymal stem cells which could be used to repair skin damage. The use of mesenchymal stem cells to repair skin damage requires safe, effective and biocompatible agents to evaluate the effectiveness of the result. Quantum dots (QDs) composed of CdSe/ZnS are semiconductor nanocrystals with broad excitation and narrow emission spectra, which have been considered as a new chemical and fluorescent substance for non-invasively labeling different cells in vitro and in vivo. This study investigated the cytotoxic effects of QDs on hAM-dMSCs at different times following labeling. METHODS: Using 0.75, 1.5 and 3.0 µL between quantum dots, labeled human amniotic mesenchymal stem cells were collected on days 1, 2 and 4 and observed morphological changes, performed an MTT cell growth assay and flow cytometry for mesenchymal stem cells molecular markers. RESULTS: Quantum dot concentration 0.75 µg/mL labeled under a fluorescence microscope, cell morphology was observed, The MTT assay showed cells in the proliferative phase. Flow cytometry expression CD29, CD31, CD34, CD44, CD90, CD105 and CD106. CONCLUSIONS: Within a certain range of concentrations between quantum dots labeled human amniotic mesenchymal stem cells has good biocompatibility.


Assuntos
Materiais Biocompatíveis/metabolismo , Células-Tronco Mesenquimais/metabolismo , Pontos Quânticos/efeitos adversos , Âmnio/citologia , Bioensaio/métodos , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia de Fluorescência/métodos , Pontos Quânticos/metabolismo , Coloração e Rotulagem/métodos
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