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1.
Proc Natl Acad Sci U S A ; 121(5): e2318718121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252820

RESUMO

Several compounds have been used for atherosclerosis treatment, including clinical trials; however, no anti-atherosclerotic drugs based on hemodynamic force-mediated atherogenesis have been discovered. Our previous studies demonstrated that "small mothers against decapentaplegic homolog 1/5" (Smad1/5) is a convergent signaling molecule for chemical [e.g., bone morphogenetic proteins (BMPs)] and mechanical (e.g., disturbed flow) stimulations and hence may serve as a promising hemodynamic-based target for anti-atherosclerosis drug development. The goal of this study was to develop a high-throughput screening (HTS) platform to identify potential compounds that can inhibit disturbed flow- and BMP-induced Smad1/5 activation and atherosclerosis. Through HTS using a Smad1/5 downstream target inhibitor of DNA binding 1 (Id-1) as a luciferase reporter, we demonstrated that KU-55933 and Apicidin suppressed Id-1 expression in AD-293 cells. KU-55933 (10 µM), Apicidin (10 µM), and the combination of half doses of each [1/2(K + A)] inhibited disturbed flow- and BMP4-induced Smad1/5 activation in human vascular endothelial cells (ECs). KU-55933, Apicidin, and 1/2(K + A) treatments caused 50.6%, 47.4%, and 73.3% inhibitions of EC proliferation induced by disturbed flow, respectively, whereas EC inflammation was only suppressed by KU-55933 and 1/2(K + A), but not Apicidin alone. Administrations of KU-55933 and 1/2(K + A) to apolipoprotein E-deficient mice inhibited Smad1/5 activation in ECs in athero-susceptible regions, thereby suppressing endothelial proliferation and inflammation, with the attenuation of atherosclerotic lesions in these mice. A unique drug screening platform has been developed to demonstrate that KU-55933 and its combination with Apicidin are promising therapeutic compounds for atherosclerosis based on hemodynamic considerations.


Assuntos
Aterosclerose , Células Endoteliais , Morfolinas , Pironas , Humanos , Animais , Camundongos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Aterosclerose/tratamento farmacológico , Hemodinâmica , Inflamação
2.
Circ Res ; 129(12): 1158-1174, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34747636

RESUMO

RATIONALE: Disturbed flow occurring in arterial branches and curvatures induces vascular endothelial cell (EC) dysfunction and atherosclerosis. We postulated that disturbed flow plays important role in modulating phosphoprotein expression profiles to regulate endothelial functions and atherogenesis. OBJECTIVE: The goal of this study is to discover novel site-specific phosphorylation alterations induced by disturbed flow in ECs to contribute to atherosclerosis. METHODS AND RESULTS: Quantitative phosphoproteomics analysis of ECs exposed to disturbed flow with low and oscillatory shear stress (0.5±4 dynes/cm2) versus pulsatile shear stress (12±4 dynes/cm2) revealed that oscillatory shear stress induces phospho-YY1S118 (serine [S]118 phosphorylation of Yin Yang 1) in ECs. Elevated phospho-YY1S118 level in ECs was further confirmed to be present in the disturbed flow regions in experimental animals and human atherosclerotic arteries. This disturbed flow-induced EC phospho-YY1S118 is mediated by CK2α (casein kinase 2α) through its direct interaction with YY1. Yeast 2-hybrid library screening and in situ proximity ligation assays demonstrate that phospho-YY1S118 directly binds ZKSCAN4 (zinc finger with KRAB [krüppel-associated box] and SCAN [SRE-ZBP, CTfin51, AW-1 and Number 18 cDNA] domains 4) to induce promoter activity and gene expression of HDM2 (human double minute 2), which consequently induces EC proliferation through downregulation of p53 and p21CIP1. Administration of apoE-deficient (ApoE-/-) mice with CK2-specific inhibitor tetrabromocinnamic acid or atorvastatin inhibits atherosclerosis formation through downregulations of EC phospho-YY1S118 and HDM2. Generation of novel transgenic mice bearing EC-specific overexpression of S118-nonphosphorylatable mutant of YY1 in ApoE-/- mice confirms the critical role of phospho-YY1S118 in promoting atherosclerosis through EC HDM2. CONCLUSIONS: Our findings provide new insights into the mechanisms by which disturbed flow induces endothelial phospho-YY1S118 to promote atherosclerosis, thus indicating phospho-YY1S118 as a potential molecular target for atherosclerosis treatment.


Assuntos
Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Aterosclerose/fisiopatologia , Sítios de Ligação , Circulação Sanguínea , Caseína Quinase II/metabolismo , Linhagem Celular , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Transcrição YY1/química , Fator de Transcrição YY1/genética , Dedos de Zinco
3.
J Am Coll Cardiol ; 72(5): 477-485, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30049307

RESUMO

BACKGROUND: Low-dose rivaroxaban (10 mg/day) has been widely used in Asia for patients with atrial fibrillation (AF), although there is a lack of evidence regarding its effectiveness. In Asians, it is unclear whether low-dose rivaroxaban is equally effective as that of the standard dose or is associated with less bleeding risk. OBJECTIVES: The aim of this study was to evaluate the effectiveness and safety of standard-dose (15 or 20 mg/day) and low-dose (10 mg/day) rivaroxaban in Asians with AF. METHODS: Using data files from the National Health Insurance Research Database between May 1, 2014, and September 30, 2015, a retrospective population-based cohort study was conducted in patients diagnosed with AF or atrial flutter and treated with low- or standard-dose rivaroxaban. Patients were followed up until the first occurrence of the study outcome or the end of the observation period (December 31, 2015). RESULTS: Among 6,558 eligible patients, a total of 2,373 and 4,185 patients took low- and standard-dose rivaroxaban, respectively. Compared to standard-dose rivaroxaban, low-dose rivaroxaban was associated with a significantly higher risk of myocardial infarction (subdistribution hazard ratio: 2.26; 95% confidence interval: 1.13 to 4.52), with similar risk of ischemic stroke, systemic embolism, major bleeding, and nonmajor clinically relevant bleeding. CONCLUSIONS: Compared to standard-dose rivaroxaban, low-dose rivaroxaban in Asian patients with AF was associated with similar risks of thromboembolism and bleeding except myocardial infarction.


Assuntos
Povo Asiático , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Inibidores do Fator Xa/uso terapêutico , Rivaroxabana/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , Estudos de Coortes , Bases de Dados Factuais/tendências , Relação Dose-Resposta a Droga , Inibidores do Fator Xa/efeitos adversos , Feminino , Hemorragia/induzido quimicamente , Hemorragia/diagnóstico , Hemorragia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rivaroxabana/efeitos adversos , Taiwan/epidemiologia , Tromboembolia/induzido quimicamente , Tromboembolia/diagnóstico , Tromboembolia/epidemiologia , Resultado do Tratamento , Adulto Jovem
4.
ScientificWorldJournal ; 2015: 740815, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25839056

RESUMO

Glucuronidation is a major metabolism process of detoxification for carcinogens, 4-(methylnitrosamino)-1-(3-pyridy)-1-butanone (NNK) and 1,2-dimethylhydrazine (DMH), of reactive oxygen species (ROS). However, intestinal E. coli ß-glucuronidase (eßG) has been considered pivotal to colorectal carcinogenesis. Specific inhibition of eßG may prevent reactivating the glucuronide-carcinogen and protect the intestine from ROS-mediated carcinogenesis. In order to develop specific eßG inhibitors, we found that 59 candidate compounds obtained from the initial virtual screening had high inhibition specificity against eßG but not human ßG. In particular, we found that compounds 7145 and 4041 with naphthalenylidene-benzenesulfonamide (NYBS) are highly effective and selective to inhibit eßG activity. Compound 4041 (IC50 = 2.8 µM) shows a higher inhibiting ability than compound 7145 (IC50 = 31.6 µM) against eßG. Furthermore, the molecular docking analysis indicates that compound 4041 has two hydrophobic contacts to residues L361 and I363 in the bacterial loop, but 7145 has one contact to L361. Only compound 4041 can bind to key residue (E413) at active site of eßG via hydrogen-bonding interactions. These novel NYBS-based eßG specific inhibitors may provide as novel candidate compounds, which specifically inhibit eßG to reduce eßG-based carcinogenesis and intestinal injury.


Assuntos
Simulação por Computador , Descoberta de Drogas/métodos , Proteínas de Escherichia coli/antagonistas & inibidores , Glucuronidase/antagonistas & inibidores , Simulação de Acoplamento Molecular/métodos , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Proteínas de Escherichia coli/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Glucuronidase/química , Glucuronidase/metabolismo , Humanos , Estrutura Secundária de Proteína
5.
ScientificWorldJournal ; 2014: 217525, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995353

RESUMO

Jia-wei-xiao-yao-san (JWXYS) is a traditional Chinese herbal medicine that is widely used to treat neuropsychological disorders. Only a few of the hepatoprotective effects of JWXYS have been studied. The aim of this study was to investigate the hepatoprotective effects of JWXYS on dimethylnitrosamine- (DMN-) induced chronic hepatitis and hepatic fibrosis in rats and to clarify the mechanism through which JWXYS exerts these effects. After the rats were treated with DMN for 3 weeks, serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) levels were significantly elevated, whereas the albumin level decreased. Although DMN was continually administered, after the 3 doses of JWXYS were orally administered, the SGOT and SGPT levels significantly decreased and the albumin level was significantly elevated. In addition, JWXYS treatment prevented liver fibrosis induced by DMN. JWXYS exhibited superoxide-dismutase-like activity and dose-dependently inhibited DMN-induced lipid peroxidation and xanthine oxidase activity in the liver of rats. Our findings suggest that JWXYS exerts antifibrotic effects against DMN-induced chronic hepatic injury. The possible mechanism is at least partially attributable to the ability of JWXYS to inhibit reactive-oxygen-species-induced membrane lipid peroxidation.


Assuntos
Dimetilnitrosamina/toxicidade , Medicamentos de Ervas Chinesas/uso terapêutico , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/prevenção & controle , Animais , Relação Dose-Resposta a Droga , Cirrose Hepática/patologia , Masculino , Ratos , Ratos Wistar
6.
Cancer ; 120(9): 1338-44, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24496917

RESUMO

BACKGROUND: Traditional Chinese medicine (TCM) is one of the most common complementary and alternative medicines used in the treatment of patients with breast cancer. However, the clinical effect of TCM on survival, which is a major concern in these individuals, lacks evidence from large-scale clinical studies. METHODS: The authors used the Taiwan National Health Insurance Research Database to conduct a retrospective population-based cohort study of patients with advanced breast cancer between 2001 and 2010. The patients were separated into TCM users and nonusers, and Cox regression models were applied to determine the association between the use of TCM and patient survival. RESULTS: A total of 729 patients with advanced breast cancer receiving taxanes were included in the current study. Of this cohort, the mean age was 52.0 years; 115 patients were TCM users (15.8%) and 614 patients were TCM nonusers. The mean follow-up was 2.8 years, with 277 deaths reported to occur during the 10-year period. Multivariate analysis demonstrated that, compared with nonusers, the use of TCM was associated with a significantly decreased risk of all-cause mortality (adjusted hazards ratio [HR], 0.55 [95% confidence interval, 0.33-0.90] for TCM use of 30-180 days; adjusted HR, 0.46 [95% confidence interval, 0.27-0.78] for TCM use of >180 days). Among the frequently used TCMs, those found to be most effective (lowest HRs) in reducing mortality were Bai Hua She She Cao, Ban Zhi Lian, and Huang Qi. CONCLUSIONS: The results of the current observational study suggest that adjunctive TCM therapy may lower the risk of death in patients with advanced breast cancer. Future randomized controlled trials are required to validate these findings.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Taxoides/uso terapêutico , Quimioterapia Adjuvante , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Fitoterapia/estatística & dados numéricos , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Taiwan/epidemiologia
7.
J Nephrol ; 26(6): 1097-104, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24052465

RESUMO

BACKGROUND: Patients with end-stage renal disease (ESRD) are at high risk of cardiovascular disease and elevated serum homocysteine levels. Although folic acid supplementation has been documented to reduce serum homocysteine levels in ESRD patients, most trials of folic acid therapy for reducing cardiovascular diseases in ESRD patients have failed, mainly because of limited patient numbers. METHODS: We used the Taiwan National Health Insurance Research Database (NHIRD) to conduct a matched-pair retrospective cohort study to clarify whether folic acid supplementation benefits ESRD patient survival. Patients were divided into a folic acid supplementation group and a control group. All-cause and cardiovascular-related mortality rates between groups were compared. RESULTS: In total, 55,636 stable incident hemodialysis patients were identified from the database. Using a propensity score-matched method and intention-to-treat analysis, the survival rate of 17,000 patients with folic acid supplementation was compared with a 1:1 matched control group. The baseline demographic data and comorbid disease incidence between the 2 groups were comparable. During the study period, the mortality rate in the matched pair cohort was 35.5% (n = 6,030) over a mean follow-up period of 3.0 years, corresponding to a mortality rate of 12.8/100 patient-years. The all-cause mortality rates were 12.3 and 13.4/100 patient-years in the folic acid group and control group, respectively (p = 0.005). CONCLUSIONS: In adult hemodialysis patients, folic acid supplementation improves cardiovascular and all-cause mortality rates.


Assuntos
Doenças Cardiovasculares/mortalidade , Ácido Fólico/administração & dosagem , Falência Renal Crônica/mortalidade , Complexo Vitamínico B/administração & dosagem , Causas de Morte , Feminino , Humanos , Análise de Intenção de Tratamento , Falência Renal Crônica/terapia , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Pontuação de Propensão , Diálise Renal , Estudos Retrospectivos , Taiwan/epidemiologia
8.
Planta Med ; 79(1): 27-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23161424

RESUMO

Topoisomerase inhibitors have been developed in a variety of clinical applications. We investigated the inhibitory effect of evodiamine on E. coli topoisomerase I, which may lead to an anti-bacterial effect. Evodiamine inhibits the supercoiled plasmid DNA relaxation that is catalyzed by E. coli topoisomerase I, and computer-aided docking has shown that the Arg161 and Asp551 residues of topoisomerase I interact with evodiamine. We investigated the bactericidal effect of evodiamine against multidrug-resistant Klebsiella pneumoniae. Evodiamine showed a significantly lower minimal inhibitory concentration value (MIC 128 µg/mL) compared with antibiotics (>512 µg/mL) against the clinical isolate of K. pneumoniae. The results suggested that evodiamine is a potential agent against drug-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Evodia/química , Klebsiella pneumoniae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quinazolinas/farmacologia , Inibidores da Topoisomerase I/farmacologia , Escherichia coli/enzimologia , Testes de Sensibilidade Microbiana
9.
J Agric Food Chem ; 58(18): 9936-41, 2010 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-20806936

RESUMO

In this study, the antihyperuricemic effect of Acacia confusa heartwood extracts and their phytochemicals on potassium oxonate (PO)-induced acute hyperuricemia was investigated for the first time. All treatments at the same dosage (100 mmol/kg) were administered to the abdominal cavity of PO-induced hyperuricemic mice, and serum uric acid level was measured at 3 h after administration. In experimental mice, serum uric acid level was significantly suppressed by the administration of A. confusa heartwood extracts and their major phytochemicals, (-)-2,3-cis-3,4-cis-3,3',4,4',7,8-hexahydroxyflavan, (-)-2,3-cis-3,4-cis-4'-methoxy-3,3',4,7,8-pentahydroxyflavan, melanoxetin, transilitin, and okanin, relative to the PO group. The direct inhibitory effect of these five compounds on xanthine oxidase (XOD) activity was examined using isothermal titration calorimetry (ITC). Among them, melanoxetin showed a more remarkable inhibitory effect on XOD activity than allopurinol, a clinical drug used for XOD inhibitor. To further understand the stereochemistry between XOD and melanoxetin (or allopurinol), structure-based molecular modeling was performed. Melanoxetin undergoes extended interactions in the hydrophobic region via the 3',4'-dihydroxyphenyl moiety, thus accounting for its higher binding affinity to XOD than allopurinol. These results indicate that A. confusa heartwood extracts and their major phytochemicals exhibit strong XOD inhibitory effects, which reduce serum uric acid levels while inhibiting uric acid generation in purine metabolism.


Assuntos
Acacia/química , Descoberta de Drogas , Inibidores Enzimáticos/uso terapêutico , Flavonoides/uso terapêutico , Hiperuricemia/tratamento farmacológico , Extratos Vegetais/química , Xantina Oxidase/antagonistas & inibidores , Animais , Inibidores Enzimáticos/toxicidade , Flavonoides/química , Flavonoides/isolamento & purificação , Hiperuricemia/sangue , Hiperuricemia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ácido Oxônico/toxicidade , Extratos Vegetais/uso terapêutico , Urato Oxidase/antagonistas & inibidores , Ácido Úrico/sangue , Madeira/química , Xantina Oxidase/química
10.
Stud Health Technol Inform ; 159: 181-90, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20543437

RESUMO

Large-scale in-silico screening is a necessary part of drug discovery and Grid computing is one answer to this demand. A disadvantage of using Grid computing is the heterogeneous computational environments characteristic of a Grid. In our study, we have found that for the molecular docking simulation program DOCK, different clusters within a Grid organization can yield inconsistent results. Because DOCK in-silico virtual screening (VS) is currently used to help select chemical compounds to test with in-vitro experiments, such differences have little effect on the validity of using virtual screening before subsequent steps in the drug discovery process. However, it is difficult to predict whether the accumulation of these discrepancies over sequentially repeated VS experiments will significantly alter the results if VS is used as the primary means for identifying potential drugs. Moreover, such discrepancies may be unacceptable for other applications requiring more stringent thresholds. This highlights the need for establishing a more complete solution to provide the best scientific accuracy when executing an application across Grids. One possible solution to platform heterogeneity in DOCK performance explored in our study involved the use of virtual machines as a layer of abstraction. This study investigated the feasibility and practicality of using virtual machine and recent cloud computing technologies in a biological research application. We examined the differences and variations of DOCK VS variables, across a Grid environment composed of different clusters, with and without virtualization. The uniform computer environment provided by virtual machines eliminated inconsistent DOCK VS results caused by heterogeneous clusters, however, the execution time for the DOCK VS increased. In our particular experiments, overhead costs were found to be an average of 41% and 2% in execution time for two different clusters, while the actual magnitudes of the execution time costs were minimal. Despite the increase in overhead, virtual clusters are an ideal solution for Grid heterogeneity. With greater development of virtual cluster technology in Grid environments, the problem of platform heterogeneity may be eliminated through virtualization, allowing greater usage of VS, and will benefit all Grid applications in general.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Design de Software , Interface Usuário-Computador , Redes de Comunicação de Computadores/normas , Bases de Dados como Assunto , Humanos
11.
J Biomed Sci ; 17: 49, 2010 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-20565729

RESUMO

BACKGROUND: The topoisomerase I (TopI) reaction intermediate consists of an enzyme covalently linked to a nicked DNA molecule, known as a TopI-DNA complex, that can be trapped by inhibitors and results in failure of re-ligation. Attempts at new derivative designs for TopI inhibition are enthusiastically being pursued, and TopI inhibitors were developed for a variety of applications. Surface plasmon resonance (SPR) was recently used in TopI-inhibition studies. However, most such immobilized small molecules or short-sequence nucleotides are used as ligands onto sensor chips, and TopI was used as the analyte that flowed through the sensor chip. METHODS: We established a sensor chip on which the TopI protein is immobilized to evaluate TopI inhibition by SPR. Camptothecin (CPT) targeting the DNA-TopI complex was used as a representative inhibitor to validate this label-free method. RESULTS: Purified recombinant human TopI was covalently coupled to the sensor chip for the SPR assay. The binding of anti-human (h)TopI antibodies and plasmid pUC19, respectively, to the immobilized hTopI was observed with dose-dependent increases in resonance units (RU) suggesting that the immobilized hTopI retains its DNA-binding activity. Neither CPT nor evodiamine alone in the analyte flowing through the sensor chip showed a significant increase in RU. The combination of pUC19 and TopI inhibitors as the analyte flowing through the sensor chip caused increases in RU. This confirms its reliability for binding kinetic studies of DNA-TopI binders for interaction and for primary screening of TopI inhibitors. CONCLUSIONS: TopI immobilized on the chip retained its bioactivities of DNA binding and catalysis of intermediates of the DNA-TopI complex. This provides DNA-TopI binders for interaction and primary screening with a label-free method. In addition, this biochip can also ensure the reliability of binding kinetic studies of TopI.


Assuntos
Enzimas Imobilizadas , Ressonância de Plasmônio de Superfície/métodos , Inibidores da Topoisomerase I , Camptotecina/metabolismo , Camptotecina/farmacologia , Ensaio Cometa , DNA/química , DNA/metabolismo , Dano ao DNA , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/metabolismo , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , Cinética , Substâncias Macromoleculares , Modelos Moleculares , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Ressonância de Plasmônio de Superfície/instrumentação
12.
J Med Chem ; 52(9): 2716-23, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19419203

RESUMO

Hepatitis C virus nonstructural protein 3 (HCV NS3) helicase is believed to be essential for viral replication and has become an attractive target for the development of antiviral drugs. A fluorescence resonant energy transfer helicase assay was established for fast screening of putative inhibitors selected from virtual screening using the program DOCK. Soluble blue HT (1) was first identified as a novel HCV helicase inhibitor. Crystal structure of the NS3 helicase in complex with soluble blue HT shows that the inhibitor bears a significantly higher binding affinity mainly through a 4-sulfonatophenylaminophenyl group, and this is consistent with the activity assay. Subsequently, fragment-based searches were utilized to identify triphenylmethane derivatives for more potent inhibitors. Lead optimization resulted in a 3-bromo-4-hydroxyl substituted derivative 12 with an EC(50) value of 2.72 microM to Ava.5/Huh-7 cells and a lower cytotoxicity to parental Huh-7 cells (CC(50) = 10.5 microM), and it indeed suppressed HCV replication in the HCV replicon cells. Therefore, these inhibitors with structural novelty may serve as a useful scaffold for the discovery of new HCV NS3 helicase inhibitors.


Assuntos
Descoberta de Drogas , Hepacivirus/enzimologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Compostos de Tritil/química , Compostos de Tritil/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Sítios de Ligação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Hepacivirus/efeitos dos fármacos , Modelos Moleculares , Replicon/efeitos dos fármacos , Software , Proteínas não Estruturais Virais/química
13.
Planta Med ; 75(11): 1237-40, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19330765

RESUMO

Caffeic acid is a xanthine oxidase (XO) inhibitor that binds to the molybdopterin region of its active site. Caffeic acid phenethyl ester (CAPE) has higher hydrophobicity and exhibits stronger inhibition potency toward XO. Chlorogenic acid is a quinyl ester of caffeic acid that has increased hydrophilicity and also shows stronger XO inhibitory activity compared with caffeic acid. Caffeic acid and CAPE showed competitive inhibition against XO, whereas chlorogenic acid displayed mixed-type inhibition, implying that it binds to sites other than the active site. Structure-based molecular modeling was performed to account for the different binding characteristics of the hydrophobic and hydrophilic esters of caffeic acid. Chlorogenic acid showed weak binding to the molybdopterin region of XO, while it more strongly bound the flavin adenine dinucleotide region than it did the molybdopterin region. These results provide the basis for interactions of caffeic acid analogues with XO via various binding domains.


Assuntos
Ácidos Cafeicos/metabolismo , Ácido Clorogênico/metabolismo , Inibidores Enzimáticos/metabolismo , Xantina Oxidase/metabolismo , Sítios de Ligação , Ácidos Cafeicos/química , Ácido Clorogênico/química , Inibidores Enzimáticos/química , Esterificação , Modelos Moleculares , Estrutura Terciária de Proteína , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/química
14.
Biorheology ; 45(5): 587-98, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19065007

RESUMO

There is evidence that hyperlipidemia can induce hemorheological and microcirculatory disturbances. Myakuryu, a Chinese traditional medicine is efficacious in promoting lipid metabolism and protecting oxidative stress, but whether this drug can ameliorate rheologic disturbances caused by hyperlipidemia is still unknown. The present study was conducted to investigate the effects of myakuryu on hemorheological and microcirculatory disturbances induced by hyperlipidemia. Wistar rats were divided into a group on control diet (n=8) and a group on high-fat diet (HFD, n=44). Eight weeks later, plasma triglyceride (TG) and total cholesterol (TC) were determined. Sixteen animals with the highest levels of hyperlipidemia from the HFD group were randomly divided into two sub-groups: the untreated hyperlipidemia group (n=8) and the group treated with myakuryu (n=8). At the end of the sixteenth week, rheological and microcirculatory parameters were measured. Chemical analysis showed that myakuryu treatment caused significant reductions of plasma TG and TC levels (P<0.01), and the cholesterol/phospholipid ratio in the erythrocyte membrane (P<0.05). Rheological and microcirculatory measurements showed that myakuryu treatment led to a significant decrease in the erythrocyte aggregation index, plasma viscosity and blood viscosity at shear rates of 50, 100 and 150 s(-1) and in adherent leukocytes in mesenteric venules. There was a significant increase in erythrocyte deformation, electrophoretic mobility, membrane fluidity and F-actin content in the erythrocyte membrane as well as in red cell velocity in mesenteric venules. Our findings suggest that myakuryu treatment can improve blood flow and reduce adherent leukocytes in the venules of rats fed with HFD by ameliorating blood viscosity, erythrocyte deformability and aggregation, and other hemorheological characteristics.


Assuntos
Hemorreologia/efeitos dos fármacos , Hiperlipidemias/sangue , Fitoterapia/métodos , Preparações de Plantas/farmacologia , Actinas/sangue , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Viscosidade Sanguínea/efeitos dos fármacos , Peso Corporal , Adesão Celular/efeitos dos fármacos , Gorduras na Dieta/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Agregação Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/fisiopatologia , Leucócitos/efeitos dos fármacos , Lipídeos/sangue , Fluidez de Membrana/efeitos dos fármacos , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/fisiopatologia , Microcirculação/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Preparações de Plantas/uso terapêutico , Ratos , Ratos Wistar
15.
J Pediatr Nurs ; 22(5): 404-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17889734

RESUMO

The purpose of this study was to explore problems encountered in self-care of adolescents with type 1 diabetes (type 1 + insulin-dependent diabetes mellitus) from a patient-oriented perspective in Taiwan. Thirteen girls and six boys were recruited for participation. An open-ended, in-depth interview method was used for data collection. Findings revealed that 26.3% to 42.1% of the subjects' self-care activities were administered by parents, 36.8% did not use any meal plan, 10% could not manage their hypoglycemia well, and 36.8% had difficulties following prescribed regimens and tried alternative therapies such as herbal medicines or nutrient supplements. Results indicate the importance of parents encouraging their children to take on self-care responsibilities. Professional staffs also need to help modify contents and schedules of regimens for each adolescent patient.


Assuntos
Adaptação Psicológica , Atitude Frente a Saúde , Diabetes Mellitus Tipo 1/psicologia , Autocuidado/psicologia , Atividades Cotidianas , Adolescente , Automonitorização da Glicemia , Terapias Complementares/estatística & dados numéricos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/prevenção & controle , Feminino , Hemoglobinas Glicadas , Promoção da Saúde , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Pesquisa Metodológica em Enfermagem , Pais/psicologia , Educação de Pacientes como Assunto , Resolução de Problemas , Psicologia do Adolescente , Autocuidado/métodos , Autoeficácia , Apoio Social , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Inquéritos e Questionários , Taiwan
16.
Phytochemistry ; 68(8): 1189-99, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17379263

RESUMO

Tyrosinase is a copper-containing monooxygenase that catalyzes melanin synthesis in skin melanocytes. Herein, 13 compounds from the Formosan apple (Malus doumeri var. formosana), an indigenous Taiwanese plant, were isolated and identified. The active constituents were identified as 3-hydroxyphloretin (7) and catechol (9); they exhibited potent hydroxyl radical-scavenging (IC(50) values, 0.6 and 1.1 microM) and cellular tyrosinase-reducing activities (IC(50) values, 32 and 22 microM) in human epidermal melanocytes. In addition, we evaluated the level of several tyrosinase-related proteins by Western blot analysis. In contrast to 3-hydroxyphloretin (7), which showed no effect on the level of these proteins, catechol (9) reduced their activity and the expression of the respective genes, as determined by quantitative real-time PCR. In a kinetic analysis of mushroom tyrosinase, 3-hydroxyphloretin (7) was a competitive inhibitor. These two constituents exhibited metal-coordinating interactions with copper ions in a virtual model of molecular docking with human tyrosinase. Thus, 3-hydroxyphloretin (7) and catechol (9) were the most active constituents from the Formosan apple; they exhibited anti-oxidant and tyrosinase reducing activities, suggesting their possible use as cosmetic agents.


Assuntos
Catecóis/farmacologia , Malus/química , Melanócitos/efeitos dos fármacos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Floretina/análogos & derivados , Agaricales/enzimologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Western Blotting , Catecóis/química , Catecóis/isolamento & purificação , Células Cultivadas , Simulação por Computador , Sequestradores de Radicais Livres/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Melaninas/biossíntese , Modelos Moleculares , Floretina/química , Floretina/isolamento & purificação , Floretina/farmacologia , Extratos Vegetais/química
17.
Asia Pac J Clin Nutr ; 15(4): 544-50, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17077073

RESUMO

Elevated inflammatory markers and muscle wasting were common in chronic obstructive pulmonary disease (COPD) patients. The purpose of this study was to investigate the effect of 7-day beta-hydroxy-beta-methylbutyrate (HMB) supplementation on inflammation, protein metabolism, and pulmonary function in COPD patients in an intensive care unit. Thirty-four COPD patients who required mechanical ventilators were randomly assigned to HMB (n=18) or control (n=16) groups. The HMB group received HMB 3 g/d for 7 days. White blood cell count, C-reactive protein, and creatinine were significantly lower, while cholesterol and total protein were significantly higher after HMB supplementation. The body weight remained unchanged in both groups. Ten subjects (55.6%) in the HMB group and 4 subjects (25.0%) in the control group had improved pulmonary function, indicated by their ventilator modes. This short-term study suggests that HMB supplementation may have anti-inflammatory and anticatabolic effect and improve pulmonary function in COPD patients in an intensive care unit setting.


Assuntos
Anti-Inflamatórios/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Valeratos/uso terapêutico , Idoso , Proteína C-Reativa/metabolismo , Colesterol/sangue , Creatinina/sangue , Suplementos Nutricionais , Metabolismo Energético/fisiologia , Feminino , Humanos , Unidades de Terapia Intensiva , Contagem de Leucócitos , Pulmão/fisiologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Testes de Função Respiratória , Resultado do Tratamento
18.
Biorheology ; 40(6): 605-12, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14610311

RESUMO

The effect of hyperbaric oxygen (HBO2) treatment on hemorheological parameters of diabetic rats was investigated. This study is a placebo-controlled, in vivo animal study. 30 streptozocin-induced diabetic rats were divided into two groups; one group received hyperbaric oxygen treatment while the other did not. Hematological and hemorheological parameters were tested with blood samples collected directly from the heart using surgical procedures. Student t-tests with a type I (alpha) error at 0.05 was used to test any significant difference between means of the hematologic and hemorheological parameters of the control (CON) and the HBO2 groups. Compared with the placebo group, hyperbaric oxygen resulted in significant higher lipid peroxidation stress of the erythrocytes and resistance of erythrocytes to deformation in rats of the HBO2 group. Whole blood viscosities measured at shear rates of 5, 150 and 400 s(-1) were all higher for the rats in the HBO2 group than those for rats in the control group. In addition, the oxygen delivery index was found to be significantly lower in rats of the HBO2 group. Thus, our work demonstrates that hyperbaric oxygen treatment significantly changes the hemorheological parameters in diabetic rats.


Assuntos
Diabetes Mellitus Experimental/sangue , Hemorreologia , Oxigenoterapia Hiperbárica , Animais , Viscosidade Sanguínea , Deformação Eritrocítica , Feminino , Peroxidação de Lipídeos , Ratos , Ratos Sprague-Dawley
19.
Nutrition ; 19(3): 257-60, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12620530

RESUMO

OBJECTIVE: This retrospective study evaluated two different modes of nutrition supplementation in premature neonates with respiratory distress syndrome. METHODS: Data were collected from the medical records of premature infants treated from January 1, 1997 to July 31, 2000. Seventeen infants were given peripheral amino acids and gradual advanced minimal hypocaloric enteral feeding within the first 48 h (early nutrition group), and 19 infants received nutrition supplementation more than 48 h after birth (late nutrition group). Groups were similar with regard to gestational age, birth weight, Apgar score, mode of delivery, and diagnosis. RESULTS: Compared with infants in the late nutrition group, those in the early nutrition group required fewer days of parenteral nutrition, fewer days to reach full enteral feeding, fewer days of mechanical ventilation, fewer days of aminophylline use, fewer days to regain birth weight, and had a lower percentage of maximal weight loss. Other physiologic parameters such as age at maximal weight loss, weight gain after day 10, and hospital days required favored the use of early nutrition. CONCLUSIONS: Early nutrition to maintain a positive energy balance in premature neonates with respiratory distress syndrome is beneficial.


Assuntos
Nutrição Enteral , Recém-Nascido Prematuro , Nutrição Parenteral , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Aumento de Peso/fisiologia , Aminoácidos/administração & dosagem , Feminino , Humanos , Recém-Nascido , Tempo de Internação , Masculino , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
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