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1.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34548400

RESUMO

The Plasmodium falciparum proteasome is a potential antimalarial drug target. We have identified a series of amino-amide boronates that are potent and specific inhibitors of the P. falciparum 20S proteasome (Pf20S) ß5 active site and that exhibit fast-acting antimalarial activity. They selectively inhibit the growth of P. falciparum compared with a human cell line and exhibit high potency against field isolates of P. falciparum and Plasmodium vivax They have a low propensity for development of resistance and possess liver stage and transmission-blocking activity. Exemplar compounds, MPI-5 and MPI-13, show potent activity against P. falciparum infections in a SCID mouse model with an oral dosing regimen that is well tolerated. We show that MPI-5 binds more strongly to Pf20S than to human constitutive 20S (Hs20Sc). Comparison of the cryo-electron microscopy (EM) structures of Pf20S and Hs20Sc in complex with MPI-5 and Pf20S in complex with the clinically used anti-cancer agent, bortezomib, reveal differences in binding modes that help to explain the selectivity. Together, this work provides insights into the 20S proteasome in P. falciparum, underpinning the design of potent and selective antimalarial proteasome inhibitors.


Assuntos
Compostos de Boro/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/química , Inibidores de Proteassoma/farmacologia , Administração Oral , Animais , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Domínio Catalítico , Humanos , Malária Falciparum/enzimologia , Malária Falciparum/parasitologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Plasmodium falciparum/enzimologia , Inibidores de Proteassoma/administração & dosagem , Inibidores de Proteassoma/química
2.
Environ Toxicol ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884142

RESUMO

Environmental antineoplastics such as sorafenib may pose a risk to humans through water recycling, and the increased risk of cardiotoxicity is a clinical issue in sorafenib users. Thus, developing strategies to prevent sorafenib cardiotoxicity is an urgent work. Empagliflozin, as a sodium-glucose co-transporter-2 (SGLT2) inhibitor for type 2 diabetes control, has been approved for heart failure therapy. Still, its cardioprotective effect in the experimental model of sorafenib cardiotoxicity has not yet been reported. Real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to study the effect of sorafenib exposure on cardiac SGLT2 expression. The impact of empagliflozin on cell viability was investigated in the sorafenib-treated cardiomyocytes using Alamar blue assay. Immunoblot analysis was employed to delineate the effect of sorafenib and empagliflozin on ferroptosis/proinflammatory signaling in cardiomyocytes. Ferroptosis/DNA damage/fibrosis/inflammation of myocardial tissues was studied in mice with a 28-day sorafenib ± empagliflozin treatment using histological analyses. Sorafenib exposure significantly promoted SGLT2 upregulation in cardiomyocytes and mouse hearts. Empagliflozin treatment significantly attenuated the sorafenib-induced cytotoxicity/DNA damage/fibrosis in cardiomyocytes and mouse hearts. Moreover, GPX4/xCT-dependent ferroptosis as an inducer for releasing high mobility group box 1 (HMGB1) was also blocked by empagliflozin administration in the sorafenib-treated cardiomyocytes and myocardial tissues. Furthermore, empagliflozin treatment significantly inhibited the sorafenib-promoted NFκB/HMGB1 axis in cardiomyocytes and myocardial tissues, and sorafenib-stimulated proinflammatory signaling (TNF-α/IL-1ß/IL-6) was repressed by empagliflozin administration. Finally, empagliflozin treatment significantly attenuated the sorafenib-promoted macrophage recruitments in mouse hearts. In conclusion, empagliflozin may act as a cardioprotective agent for humans under sorafenib exposure by modulating ferroptosis/DNA damage/fibrosis/inflammation. However, further clinical evidence is required to support this preclinical finding.

3.
BMC Med Educ ; 24(1): 132, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341547

RESUMO

BACKGROUND: Longitudinal integrated clerkships (LICs) and traditional block rotations (TBRs) employ different designs that provide various learning experiences for students. In this study, we explored students' clinical participation and interpersonal interactions in LICs and TBRs at 2 metropolitan hospitals in Taiwan. METHODS: In April 2018, we enrolled 15 LIC and 29 TBR students. We conducted a cross-sectional survey which required the students to outline a typical daily schedule during their internal medicine rotations and draw an ecomap of the clinical team members. With the patient in the center as a reference, the size of each circle in an ecomap indicated the importance of the member; the distances and number of connecting lines between two circles represented the relationship and frequency of interaction, respectively, between the corresponding members. We analyzed the results and compared the responses of the LIC and TBR students. RESULTS: The LIC students spent more time on direct patient care and in the outpatient clinic/operation room, whereas the TBR students participated more in educational activities and in observation behind their seniors. In the ecomap analysis, the LIC students had a closer relationship with attending physicians and had better interactions with patients and preceptors than did the TBR students. Conversely, the TBR students felt closer to and interacted more frequently with interns and residents. CONCLUSIONS: The LIC students had more opportunities to care for patients directly and engaged in interactions with patients and attending physicians more frequently than did the TBR students. TRIAL REGISTRATION: Ethical approval for the study was obtained from the Institutional Review Board of Tri-Service General Hospital (TSGHIRB 2-106-05-018).


Assuntos
Estágio Clínico , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Taiwan , Estudos Transversais , Estágio Clínico/métodos
4.
Biochem Biophys Res Commun ; 550: 70-76, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33689882

RESUMO

T cells secrete several inflammatory cytokines that play a critical role in the progression of atherosclerosis. Although green tea epigallocatechin-3-gallate (EGCG) exerts anti-inflammatory and anti-atherosclerotic effects in animals, few studies have identified the mechanism underlying these effects in human primary T cells. This study investigated the pathway involved in EGCG modulation of cytokine secretion in activated human primary T cells. We pre-treated human primary T cells with EGCG (0.1, 1, 5, 10, and 20 µM) for 4 h and incubated them with or without phorbol 12-myristate 13-acetate and ionomycin (P/I) for 20 h. The cytokine production, activator protein (AP)-1 binding activity, and level of mitogen-activated protein kinase (MAPK) were assessed using enzyme-linked immunosorbent assay, electrophoretic mobility shift assay, and Western blotting, respectively. At 10 and 20 µM, EGCG decreased interleukin (IL)-2 levels by 26.0% and 38.8%, IL-4 levels by 41.5% and 55.9%, INF-γ levels by 31.3% and 34.7%, and tumor-necrosis factor (TNF)-α levels by 23.0% and 37.6%, respectively. In addition, the level of phosphorylated c-Jun N-terminal (p-JNK) and extracellular signal-regulated kinase (p-ERK) was decreased, but not the level of p-p38 MAPK. EGCG did not alter any of the total protein amounts, suggesting a selective effect on specific types of MAPKs in stimulated human T cells. EGCG tended to inactivate AP-1 DNA-binding activity. The P/I-induced production of IL-2, IL-4, INF-γ, and TNF-α by human T cells was suppressed by AP-1 inhibitor in a concentration-dependent manner. In conclusion, EGCG suppressed cytokine secretion in activated human primary T cells, and this effect was likely mediated by AP-1 inactivation through the ERK and JNK, but not p38 MAPK, pathways. These results may be related to the mechanisms through which EGCG inhibits immune- or inflammation-related atherogenesis.


Assuntos
Catequina/análogos & derivados , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/farmacologia , Catequina/imunologia , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Ativação Linfocitária/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/metabolismo , Fator de Transcrição AP-1/metabolismo
5.
Bioorg Med Chem ; 28(19): 115681, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32912429

RESUMO

Autophagy is postulated to be required by cancer cells to survive periods of metabolic and/or hypoxic stress. ATG7 is the E1 enzyme that is required for activation of Ubl conjugation pathways involved in autophagosome formation. This article describes the design and optimization of pyrazolopyrimidine sulfamate compounds as potent and selective inhibitors of ATG7. Cellular levels of the autophagy markers, LC3B and NBR1, are regulated following treatment with these compounds.


Assuntos
Proteína 7 Relacionada à Autofagia/antagonistas & inibidores , Descoberta de Drogas , Pirazóis/farmacologia , Pirimidinas/farmacologia , Ácidos Sulfônicos/farmacologia , Autofagia/efeitos dos fármacos , Proteína 7 Relacionada à Autofagia/metabolismo , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Ácidos Sulfônicos/síntese química , Ácidos Sulfônicos/química
6.
BMC Cancer ; 19(1): 1083, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711427

RESUMO

BACKGROUND: Hepatoma-derived growth factor (HDGF) participates in angiogenesis and represents a negative prognostic factor in oral cancer. The current study was designed to elucidate the regulatory mechanism between HDGF and vascular endothelial growth factor (VEGF) and the clinical impact of oral cancer. METHODS: TCGA data and surgical samples from oral cancer patients were used for the clinicopathological parameter and survival analysis. Human oral cancer SCC4 and SAS cells were treated with recombinant HDGF protein. VEGF gene expression and protein level were analyzed by RT-PCR, Western blotting, and enzyme-linked immunosorbent assay. The signaling pathways for regulating VEGF expression were investigated. The nucleolin neutralizing antibody and HIF-1α inhibitor were applied to SCC4 cells to investigate their effects on the HDGF-stimulated VEGF pathways. RESULTS: TCGA and immunohistochemical analysis revealed a positive correlation between HDGF and VEGF expression in oral cancer tissues. Recombinant HDGF significantly increased VEGF gene and protein expression in oral cancer SCC4 cells in a dose-dependent manner. HDGF enhanced the phosphorylation levels of AKT and IkB and the protein level of HIF-1α and NF-κB. The nucleolin-neutralizing antibody abolished HDGF-stimulated HIF-1α, NF-κB and VEGF protein expression in SCC4 cells. The HIF-1α inhibitor antagonized the HDGF-induced VEGF gene expression. High VEGF expression was strongly correlated with HDGF expression, advanced disease, and poor survival. CONCLUSION: This study postulated a new pathway in which HDGF activated HIF-1α and then induced VEGF expression through binding to membrane nucleolin under normoxic conditions, leading to poor disease control. The HDGF/HIF-1α/VEGF axis is important for developing future therapeutic strategies.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Prognóstico , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fator A de Crescimento do Endotélio Vascular/genética
7.
Lab Invest ; 98(8): 999-1013, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29789683

RESUMO

Transforming growth factor-ß (TGF-ß) plays a central role in hepatic fibrogenesis. This study investigated the function and mechanism of bone morphogenetic protein-2 (BMP-2) in regulation of hepatic fibrogenesis. BMP-2 expression in fibrotic liver was measured in human tissue microarray and mouse models of liver fibrosis induced by bile duct ligation surgery or carbon tetrachloride administration. Adenovirus-mediated BMP-2 gene delivery was used to test the prophylactic effect on liver fibrosis. Primary hepatic stellate cells (HSC), HSC-T6 and clone-9 cell lines were used to study the interplay between BMP-2 and TGF-ß1. Hepatic BMP-2 was localized in parenchymal hepatocytes and activated HSCs and significantly decreased in human and mouse fibrotic livers, showing an opposite pattern of hepatic TGF-ß1 contents. BMP-2 gene delivery alleviated the elevations of serum hepatic enzymes, cholangiocyte marker CK19, HSC activation markers, and liver fibrosis in both models. Mechanistically, exogenous TGF-ß1 dose dependently reduced BMP-2 expression, whereas BMP-2 significantly suppressed expression of TGF-ß and its cognate type I and II receptor peptides, as well as the induced Smad3 phosphorylation levels in primary mouse HSCs. Aside from its suppressive effects on cell proliferation and migration, BMP-2 treatment prominently attenuated the TGF-ß1-stimulated α-SMA and fibronectin expression, and reversed the TGF-ß1-modulated epithelial-to-mesenchymal transition marker expression in mouse HSCs. The mutual regulation between BMP-2 and TGF-ß1 signaling axes may constitute the anti-fibrogenic mechanism of BMP-2 in the pathogenesis of liver fibrosis. BMP-2 may potentially serve as a novel therapeutic target for treatment of liver fibrosis.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Humanos , Fígado/patologia , Cirrose Hepática/genética , Camundongos , Ratos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/farmacologia
8.
Int J Mol Sci ; 19(12)2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30513637

RESUMO

α-melanocyte-stimulating hormone (α-MSH) has been characterized as a novel angiogenesis inhibitor. The homeostasis of nitric oxide (NO) plays an important role in neovascularization. However, it remains unclear whether α-MSH mitigates angiogenesis through modulation of NO and its signaling pathway. The present study elucidated the function and mechanism of NO signaling in α-MSH-induced angiogenesis inhibition using cultured human umbilical vein endothelial cells (HUVECs), rat aorta rings, and transgenic zebrafish. By Griess reagent assay, it was found α-MSH dose-dependently reduced the NO release in HUVECs. Immunoblotting and immunofluorescence analysis revealed α-MSH potently suppressed endothelial and inducible nitric oxide synthase (eNOS/iNOS) expression, which was accompanied with inhibition of nuclear factor kappa B (NF-κB) activities. Excessive supply of NO donor l-arginine reversed the α-MSH-induced angiogenesis inhibition in vitro and in vivo. By using antibody neutralization and RNA interference, it was delineated that melanocortin-1 receptor (MC1-R) and melanocortin-2 receptor (MC2-R) participated in α-MSH-induced inhibition of NO production and NF-κB/eNOS/iNOS signaling. This was supported by pharmaceutical inhibition of protein kinase A (PKA), the downstream effector of MC-Rs signaling, using H89 abolished the α-MSH-mediated suppression of NO release and eNOS/iNOS protein level. Therefore, α-MSH exerts anti-angiogenic function by perturbing NO bioavailability and eNOS/iNOS expression in endothelial cells.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , NF-kappa B/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Receptores de Melanocortina/metabolismo , alfa-MSH/uso terapêutico , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos
9.
Kidney Blood Press Res ; 42(5): 919-932, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29161690

RESUMO

BACKGROUND/AIMS: We explored the effects of catechins (decaffeinated green tea extracts containing (-)-epicatechin, (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epigallocatechin gallate) on atherosclerosis risk factors, oxidized low-density lipoprotein (oxLDL) and its primary metabolite, phosphatidylcholine hydroperoxide (PCOOH) induced oxidative injury in cultured endothelial cell line and rats. METHODS: We used endothelial cell line and male Wistar rats to determine the effect of catechins on oxLDL or PCOOH induced oxidative injury including apoptosis, H2O2 level, vascular responses and urinary 8-isoprostane and nitrite/nitrate concentration. Plasma catechins concentration was determined by a CoulArray HPLC. Responses of aortic and renal vasoconstriction were evaluated by a transonic meter and a full-field laser perfusion imager. RESULTS: PCOOH administration significantly increased H2O2 amounts and cell apoptosis and decreased endothelial nitric oxide synthase (eNOS) expression in the cultured endothelial cells. Catechins pretreatment significantly reduced PCOOH-elevated H2O2 amounts, endothelial cell apoptosis and partly recovered eNOS expression. Intravenous administration of oxLDL, PCOOH or H2O2, not native LDL, significantly decreased renal and aortic blood flow associated with enhanced ICAM-1 expression and 4-hydroxynoneal (4-HNE) accumulation, and decreased eNOS expression in the male Wistrar rats. One hour after oral intake of green tea extracts, 4 peaks of catechins were found in the rat plasma. The increased plasma catechins significantly inhibited oxLDL-, PCOOH- or H2O2-induced renal and aortic vasoconstriction, decreased urinary 8-isoprostane levels, renal ICAM-1 expression and 4-HNE accumulation, and restored nitrite/nitrate amounts and eNOS activity. CONCLUSIONS: Our data suggests that catechins pretreatment decrease PCOOH-induced endothelial apoptosis and arterial vasoconstriction through the action of H2O2 inhibition and eNOS restoration.


Assuntos
Catequina/farmacologia , Endotélio Vascular/fisiopatologia , Lipoproteínas LDL/farmacologia , Óxido Nítrico Sintase Tipo III/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilcolinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Catequina/uso terapêutico , Linhagem Celular , Humanos , Peróxido de Hidrogênio/farmacologia , Masculino , Ratos , Ratos Wistar , Vasoconstrição/efeitos dos fármacos
10.
Bioorg Med Chem Lett ; 26(4): 1156-60, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26804230

RESUMO

Investigations of a biaryl ether scaffold identified tetrahydronaphthalene Raf inhibitors with good in vivo activity; however these compounds had affinity toward the hERG potassium channel. Herein we describe our work to eliminate this hERG activity via alteration of the substituents on the benzoic amide functionality. The resulting compounds have improved selectivity against the hERG channel, good pharmacokinetic properties and potently inhibit the Raf pathway in vivo.


Assuntos
Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Tetra-Hidronaftalenos/química , Animais , Linhagem Celular Tumoral , Canais de Potássio Éter-A-Go-Go/metabolismo , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Mutagênese , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Ligação Proteica , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Tetra-Hidronaftalenos/farmacocinética , Tetra-Hidronaftalenos/uso terapêutico , Transplante Heterólogo
11.
Acta Cardiol Sin ; 32(2): 247-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122957

RESUMO

UNLABELLED: Pulmonary embolism (PE) is a complication of underlying vascular thrombosis. The causes of PE are multi-factorial, and patients with PE present with various symptoms. We herein have presented the case of a 21-year-old man who initially developed palpitation, dyspnea, and seizure. Computed tomography of the chest ultimately indicated PE, and antiphospholipid syndrome (APS) was diagnosed with clinical thrombosis events and series presence of antiphospholipid antibodies. APS commonly causes vascular thrombosis within the vascular tree; however, nonthrombotic manifestations, such as seizure, may also occur. Clinicians should be aware of such non-thrombotic manifestations of APS to avoid misdiagnosis and inappropriate management. KEY WORDS: Antiphospholipid syndrome • Pulmonary embolism • Seizure.

12.
Biochim Biophys Acta ; 1840(6): 1850-60, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24530634

RESUMO

BACKGROUND: Gene therapy of proopiomelanocortin, the precursor of α-melanocyte-stimulating hormone (α-MSH), suppresses the neovascularization in tumors. However, the roles of α-MSH in angiogenesis remain unclear. METHODS: The influence of α-MSH on angiogenesis was evaluated by ex vivo rat aorta and in vivo, including transgenic zebrafish and chicken chorioallantoic membrane (CAM) assays. The effect of α-MSH on proliferation, matrix metalloproteinase (MMP) secretion, migration and tube formation was examined using human umbilical vein endothelial cells (HUVECs). The expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) was investigated by quantitative RT-PCR, immunoblot and immunofluorescent analysis. Antibodies' neutralization was employed to dissect the receptor(s) transmitting α-MSH signaling. RESULTS: Application of α-MSH potently suppressed the microvessels sprouting in organotypic aortic rings. Besides, α-MSH perturbed the vessels development in zebrafish and chicken embryos. α-MSH (0.01-10nM) inhibited the MMP-2 secretion, migration and tube formation of HUVECs without affecting proliferation. Mechanistic studies unveiled α-MSH decreased the VEGF expression and release in HUVECs. Besides, α-MSH downregulated the VEGFR2 expression at transcriptional and translational levels. Importantly, α-MSH attenuated the Akt phosphorylation, but enhanced the expression of PTEN, endogenous antagonist of PI3K/Akt signaling. Expression analysis and antibody neutralization revealed that MC1-R and MC2-R participated in α-MSH-induced blockage of migration and VEGF/VEGFR2/Akt signaling. However, VEGF supply failed to reverse the anti-angiogenic function of α-MSH. CONCLUSIONS: α-MSH inhibits the physiological angiogenesis by attenuating VEGF/VEGFR2/Akt signaling in endothelial cells. GENERAL SIGNIFICANCE: α-MSH is a potent angiogenesis inhibitor targeting at endothelial VEGF/VEGFR2 signaling, which may have potential for therapeutic application.


Assuntos
Inibidores da Angiogênese/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/fisiologia , alfa-MSH/farmacologia , Animais , Células Cultivadas , Humanos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , PTEN Fosfo-Hidrolase/análise , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Melanocortina/fisiologia , Receptor Tipo 2 de Melanocortina/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Peixe-Zebra
13.
Am J Emerg Med ; 33(8): 1117.e3-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25701214

RESUMO

Extrinsic esophageal compression leading to dysphagia is an uncommon and late presentation of large thoracic aortic aneurysm named dysphagia aortica. Herein, we report an 86-year-old man who presented with 1-week duration of chest pain, backache, and dysphagia and was eventually diagnosed as dysphagia aortica. Our patient developed progressive dyspnea due to tracheal compression and failed surgery. The case illustrates the importance of early identification of the rare entity of dysphagia especially in elderly cases with cardiovascular disease with complaint of undetermined dysphagia accompanied with chest pain and backache.


Assuntos
Aneurisma da Aorta Torácica/diagnóstico , Transtornos de Deglutição/etiologia , Diagnóstico Tardio , Idoso de 80 Anos ou mais , Aneurisma da Aorta Torácica/complicações , Evolução Fatal , Humanos , Masculino
14.
Mar Drugs ; 13(2): 861-78, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25668036

RESUMO

BACKGROUND: WA-25 (dihydroaustrasulfone alcohol, a synthetic derivative of marine compound WE-2) suppresses atherosclerosis in rats by reducing neointima formation. Because angiogenesis plays a critical role in the pathogenesis of atherosclerosis, the present study investigated the angiogenic function and mechanism of WA-25. METHODS: The angiogenic effect of WA-25 was evaluated using a rat aortic ring assay and transgenic zebrafish models were established using transgenic Tg(fli-1:EGFP)y1 and Tg(kdrl:mCherryci5-fli1a:negfpy7) zebrafish embryos. In addition, the effect of WA-25 on distinct angiogenic processes, including matrix metalloproteinase (MMP) expression, endothelial cell proliferation and migration, as well as tube formation, was studied using human umbilical vein endothelial cells (HUVECs). The effect of WA-25 on the endothelial vascular endothelial growth factor (VEGF) signaling pathway was elucidated using qRT-PCR, immunoblot analysis, immunofluorescence and flow cytometric analyses. RESULTS: The application of WA-25 perturbed the development of intersegmental vessels in transgenic zebrafish. Moreover, WA-25 potently suppressed microvessel sprouting in organotypic rat aortic rings. Among cultured endothelial cells, WA-25 significantly and dose-dependently inhibited MMP-2/MMP-9 expression, proliferation, migration and tube formation in HUVECs. Mechanistic studies revealed that WA-25 significantly reduced the VEGF release by reducing VEGF expression at the mRNA and protein levels. In addition, WA-25 reduced surface VEGF receptor 2 (VEGFR2/Flk-1) expression by repressing the VEGFR2 mRNA level. Finally, an exogenous VEGF supply partially rescued the WA-25-induced angiogenesis blockage in vitro and in vivo. CONCLUSIONS: WA-25 is a potent angiogenesis inhibitor that acts through the down-regulation of VEGF and VEGFR2 in endothelial cells. GENERAL SIGNIFICANCE: WA-25 may constitute a novel anti-angiogenic drug that acts by targeting endothelial VEGF/VEGFR2 signaling.


Assuntos
Inibidores da Angiogênese/farmacologia , Antozoários/química , Butanonas/farmacologia , Sulfonas/farmacologia , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Masculino , Inibidores de Metaloproteinases de Matriz/farmacologia , Neovascularização Patológica/prevenção & controle , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra
15.
Acta Cardiol Sin ; 30(2): 157-64, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122783

RESUMO

BACKGROUND: Typical electrocardiographic (ECG) changes associated with left primary spontaneous pneumothorax (PSP) have previously been well-described. However, there were no reports in the literature about the characteristic of ECG in estimating the severity of pneumothorax. METHODS: From 2003 through 2008, 63 male patients who had left PSP were divided into two groups: 1) large PSP, Light index ≥ 20% (n = 43), and 2) small PSP, Light index < 20% (n = 20). The ECGs of 64 age-matched disease-free men were used as the normal control. Those medical records reviewed that provided data for this study included patient backgrounds, severity of PSP, and 12-lead ECG characteristics. RESULTS: As compared to the normal controls, left PSP patients had lower body mass index, more rapid heart beat rate and lower voltages in V3R-V6R. In analyzing QRS voltages, the amplitudes of V2S and V3S were significantly different. As with both V2S < 12 mm and V3S < 9 mm, the sensitivity, specificity and positive predictive value to predict patients who had large left PSP area were estimated at 42% (18/43), 100% (20/20) and 100% (18/18), respectively. CONCLUSIONS: Using the criteria of V2S < 12 mm, V3S < 9 mm and electrical alternans could predict pneumothorax size exceeding 20% in patients who already had left PSP. KEY WORDS: 12-lead electrocardiogram; Male; Primary spontaneous pneumothorax.

16.
J Microbiol Immunol Infect ; 57(2): 309-319, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38199822

RESUMO

INTRODUCTION: Early enteral nutrition (EN) is a nutritional strategy for reducing the incidence of in-hospital infections. However, the benefits of early EN, under targeted temperature management (TTM) in patients with out-of-hospital cardiac arrest (OHCA), remain unclear. We aimed to evaluate the effect of early EN on the infective complications of OHCA patients who underwent TTM. METHODS: We retrospectively searched the clinical databases of two adult emergency tertiary referral hospitals in southern Taiwan and identified patients admitted for OHCA who underwent TTM between 2017 and 2022. The 85 enrolled patients were divided into two groups based on timing: early EN (EN within 48 h of admission) and delayed EN (EN > 48 h after admission). Clinical outcomes of 7-day infective complications between the two groups were analyzed. RESULTS: Early EN was provided to 57 (67 %) of 85 patients and delayed EN was provided to the remaining 28 (33 %) patients. No significant differences in baseline patient characteristics were observed between the two groups. In addition, no differences in clinical outcomes were observed, except that the early EN group had a lower 7-day bacteremia rate (5.3 % vs. 26.9 %, p = 0.013). Gram-negative bacteria were the major pathogen among the 7-day infective complications. CONCLUSION: In OHCA patients treated with TTM, early EN was associated with a lower 7-day bacteremia rate. Furthermore, the application of early EN in this population was well tolerated without significant adverse events.


Assuntos
Bacteriemia , Parada Cardíaca Extra-Hospitalar , Humanos , Nutrição Enteral , Estudos Retrospectivos , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/complicações , Temperatura , Bacteriemia/complicações
17.
Artigo em Inglês | MEDLINE | ID: mdl-36981892

RESUMO

To investigate the relationship between chronic liver disease and tendon disorder, a retrospective cohort study was conducted using the Kaohsiung Veterans General Hospital database. Patients >18 years with newly diagnosed liver disease and with at least a two-year follow-up in the hospital were included. An equal number of 20,479 cases were enrolled in both the liver-disease and non-liver-disease groups using a propensity score matching method. Disease was defined using ICD-9 or ICD-10 codes. The primary outcome was the development of tendon disorder. Demographic characteristics, comorbidities, use of tendon-toxic drugs, and status of HBV/HCV infection were included for analysis. The results showed 348 (1.7%) and 219 (1.1%) individuals developed tendon disorder in the chronic liver disease group and non-liver-disease group. Concomitant use of glucocorticoids and statins may have further raised the risk of tendon disorder in the liver disease group. The co-existence of HBV/HCV infection did not increase the risk of tendon disorder in the patients with liver disease. Considering these findings, physicians should be more aware of tendon issues in advance, and a prophylactic strategy should be adopted in patients with chronic liver disease.


Assuntos
Hepatite C , Hepatopatias , Humanos , Estudos Retrospectivos , Taiwan/epidemiologia , Hepatopatias/complicações , Hepatopatias/epidemiologia , Tendões
18.
Gene ; 865: 147331, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36871674

RESUMO

Slow skeletal muscle troponin T (TNNT1) as a poor prognostic indicator is upregulated in colon and breast cancers. However, the role of TNNT1 in the disease prognosis and biological functions of hepatocellular carcinoma (HCC) is still unclear. The Cancer Genome Atlas (TCGA), real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to evaluate the TNNT1 expression of human HCC. The impact of TNNT1 levels on disease progression and survival outcome was studied using TCGA analysis. Moreover, the bioinformatics analysis and HCC cell culture were used to investigate the biological functions of TNNT1. Besides, the immunoblot analysis and enzyme-linked immunosorbent assay (ELISA) were used to detect the extracellular TNNT1 of HCC cells and circulating TNNT1 of HCC patients, respectively. The effect of TNNT1 neutralization on oncogenic behaviors and signaling was further validated in the cultured hepatoma cells. In this study, tumoral and blood TNNT1 was upregulated in HCC patients based on the analyses using bioinformatics, fresh tissues, paraffin sections, and serum. From the multiple bioinformatics tools, the TNNT1 overexpression was associated with advanced stage, high grade, metastasis, vascular invasion, recurrence, and poor survival outcome in HCC patients. By the cell culture and TCGA analyses, TNNT1 expression and release were positively correlated with epithelial-mesenchymal transition (EMT) processes in HCC tissues and cells. Moreover, TNNT1 neutralization suppressed oncogenic behaviors and EMT in hepatoma cells. In conclusion, TNNT1 may serve as a non-invasive biomarker and drug target for HCC management. This research finding may provide a new insight for HCC diagnosis and treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Músculo Esquelético/metabolismo , Prognóstico , Troponina T/genética
19.
Environ Pollut ; 327: 121476, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36997141

RESUMO

Plasticizers are considered as environmental pollution released from medical devices and increased potential oncogenic risks in clinical therapy. Our previous studies have shown that long-term exposure to di-ethylhexyl phthalate (DEHP)/mono-ethylhexyl phthalate (MEHP) promotes chemotherapeutic drug resistance in colorectal cancer. In this study, we investigated the alteration of glycosylation in colorectal cancer following long-term plasticizers exposure. First, we determined the profiles of cell surface N-glycomes by using mass spectrometry and found out the alterations of α2,8-linkages glycans. Next, we analyzed the correlation between serum DEHP/MEHP levels and ST8SIA6 expression from matched tissues in total 110 colorectal cancer patients. Moreover, clinical specimens and TCGA database were used to analyze the expression of ST8SIA6 in advanced stage of cancer. Finally, we showed that ST8SIA6 regulated stemness in vitro and in vivo. Our results revealed long-term DEHP/MEHP exposure significantly caused cancer patients with poorer survival outcome and attenuated the expression of ST8SIA6 in cancer cells and tissue samples. As expected, silencing of ST8SIA6 promoted cancer stemness and tumorigenicity by upregulating stemness-associated proteins. In addition, the cell viability assay showed enhanced drug resistance in ST8SIA6 silencing cells treated with irinotecan. Besides, ST8SIA6 was downregulated in the advanced stage and positively correlated with tumor recurrence in colorectal cancer. Our results imply that ST8SIA6 potentially plays an important role in oncogenic effects with long-term phthalates exposure.


Assuntos
Neoplasias Colorretais , Dietilexilftalato , Humanos , Plastificantes/análise , Dietilexilftalato/análise , Glicosilação , Sialiltransferases/metabolismo
20.
Blood Press ; 21 Suppl 1: 11-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22809200

RESUMO

AIMS: To assess safety and efficacy of valsartan/amlodipine combination in hypertensive Taiwanese patients. METHODS: This 12-week, multi-center, prospective, observational, post-marketing study enrolled 1029 patients to receive valsartan/amlodipine combination alone or as add-on to other antihypertensives. Efficacy was evaluated by blood pressure (BP) control rate (in mmHg; non-diabetics, < 140/90; diabetics, < 130/80) at Week 12 and BP-lowering ability at Weeks 4 and 12. Additionally, responder rate (sitting-SBP < 140 for baseline SBP ≥ 140 or sitting-DBP < 90 for baseline DBP ≥ 90, or SBP reduction > 20 or DBP reduction > 10 from baseline) was determined. MAJOR FINDINGS: Adverse events (AEs) were reported in 12.15% patients; dizziness, cough, and peripheral edema were the most commonly reported AEs. Overall BP control rate was 48.27%. Greater BP reduction was noted at Week 12 than at Week 4 between all groups and subgroups. Greater SBP/DBP reduction was observed in patients with stage 2 hypertension than stage 1 hypertension at baseline. The overall responder rate was 78.52%. Subgroup analysis showed greater BP reduction in non-diabetics than diabetics; only SBP reduction reached statistical significance (- 13.7 [18.3] vs. - 10.7 [17.4] mmHg; p < 0.0093). PRINCIPAL CONCLUSION: Valsartan/amlodipine combination was well tolerated, with no safety concerns identified and an effective treatment option for hypertensive Taiwanese patients.


Assuntos
Anlodipino/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Hipertensão/tratamento farmacológico , Vigilância de Produtos Comercializados , Tetrazóis/administração & dosagem , Valina/análogos & derivados , Idoso , Anlodipino/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Povo Asiático , Pressão Sanguínea , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taiwan/epidemiologia , Tetrazóis/efeitos adversos , Fatores de Tempo , Valina/administração & dosagem , Valina/efeitos adversos , Valsartana
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