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1.
Phytomedicine ; 107: 154457, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36223697

RESUMO

BACKGROUND: Auraptene derived from the peel of Citrus hassaku possesses anti-tumor, anti-inflammatory, and neuroprotective activities. Thus, it could be a valuable pharmacological alternative to treat some diseases. However, the therapeutic value of auraptene for heart failure (HF) is unknown. STUDY DESIGN/METHODS: In cultured cardiomyocytes from neonatal rats, the effect of auraptene on phenylephrine-induced hypertrophic responses and peroxisome proliferator-activated receptor-alpha (PPARα)-dependent gene transcriptions. To investigate whether auraptene prevents the development of heart failure after myocardial infarction (MI) in vivo, Sprague-Dawley rats with moderate MI (fractional shortening < 40%) were randomly assigned for treatment with low- or high-dose auraptene (5 or 50 mg/kg/day, respectively) or vehicle for 6 weeks. The effects of auraptene were evaluated by echocardiography, histological analysis, and the measurement of mRNA levels of hypertrophy, fibrosis, and PPARα-associated genes. RESULTS: In cultured cardiomyocytes, auraptene repressed phenylephrine-induced hypertrophic responses, such as increases in cell size and activities of atrial natriuretic factor and endothelin-1 promoters. Auraptene induced PPARα-dependent gene activation by enhancing cardiomyocyte peroxisome proliferator-responsive element reporter activity. The inhibition of PPARα abrogated the protective effect of auraptene on phenylephrine-induced hypertrophic responses. In rats with MI, auraptene significantly improved MI-induced systolic dysfunction and increased posterior wall thickness compared to the vehicle. Auraptene treatment also suppressed MI-induced increases in myocardial cell diameter, perivascular fibrosis, and expression of hypertrophy and fibrosis response markers at the mRNA level compared with vehicle treatment. MI-induced decreases in the expression of PPARα-dependent genes were improved by auraptene treatment. CONCLUSIONS: Auraptene has beneficial effects on MI-induced cardiac hypertrophy and left ventricular systolic dysfunction in rats, at least partly due to PPARα activation. Further clinical studies are required to evaluate the efficacy of auraptene in patients with HF.


Assuntos
Produtos Biológicos , Citrus , Insuficiência Cardíaca , Infarto do Miocárdio , Animais , Ratos , Fator Natriurético Atrial , Produtos Biológicos/uso terapêutico , Cardiomegalia/tratamento farmacológico , Cumarínicos , Endotelina-1 , Fibrose , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Infarto do Miocárdio/tratamento farmacológico , Proliferadores de Peroxissomos/uso terapêutico , Fenilefrina , PPAR alfa/metabolismo , Ratos Sprague-Dawley , RNA Mensageiro
2.
Nutrients ; 14(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35276939

RESUMO

Ecklonia stolonifera Okamura extract (ESE) has been reported to have various bioactive effects, but its effects on cardiovascular disease have not yet been investigated. First, primary neonatal rat cultured cardiomyocytes were treated with ESE and stimulated with phenylephrine (PE) for 48 h. ESE (1000 µg/mL) significantly suppressed PE-induced cardiomyocyte hypertrophy, hypertrophy-related gene transcription, and the acetylation of histone H3K9. An in vitro p300-HAT assay indicated that ESE directly inhibited p300-HAT activity. Next, one week after myocardial infarction (MI) surgery, rats (left ventricular fractional shortening (LVFS) < 40%) were randomly assigned to three groups: vehicle (saline, n = 9), ESE (0.3 g/kg, n = 10), or ESE (1 g/kg, n = 10). Daily oral administration was carried out for 8 weeks. After treatment, LVFS was significantly higher in the ESE (1 g/kg) group than in the vehicle group. The ESE treatments also significantly suppressed MI-induced increases in myocardial cell diameter, perivascular fibrosis, hypertrophy- and fibrosis-related gene transcription, and the acetylation of histone H3K9. These results suggest that ESE suppressed both hypertrophic responses in cardiomyocytes and the development of heart failure in rats by inhibiting p300-HAT activity. Thus, this dietary extract is a potential novel therapeutic strategy for heart failure in humans.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Phaeophyceae , Animais , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos
3.
J Med Food ; 24(11): 1186-1190, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34698557

RESUMO

Black tea is a popular beverage worldwide. Theaflavins (TFs), which are active functional components of black tea, are potentially valuable for preventing and/or treating the progression of periodontal diseases. Our previous pilot study showed that TF intake decreases the number of Porphyromonas gingivalis (P. gingivalis) bacteria in the saliva. In this study, we aimed to determine whether TF intake improves periodontal disease attributed to oral bacteria in a randomized, placebo-controlled, and double-blind study. A total of 56 healthy subjects without periodontal diseases were enrolled and assigned to the placebo and TF groups (n = 28). TF intake for 6 weeks did not significantly alter the clinical evaluation of subjects. There was no significant adverse effect among the subjects. The number of P. gingivalis and Fusobacterium nucleatum (F. nucleatum) bacteria, which was the primary endpoint in this study, was not impacted by TF intake. The change ratio of Prevotella intermedia was significantly decreased by TF intake (P = .043) when compared with the placebo group. Collectively, our findings suggest that TFs have beneficial effects on oral bacteria for the prevention of periodontal disease. The study protocol was registered in the University Hospital Medical Information Network (UMIN000020049).


Assuntos
Fusobacterium nucleatum , Porphyromonas gingivalis , Aggregatibacter actinomycetemcomitans , Biflavonoides , Catequina , Método Duplo-Cego , Humanos , Japão , Projetos Piloto
4.
Phytomedicine ; 92: 153744, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34563985

RESUMO

BACKGROUND: Cardiac hypertrophy and fibrosis are hallmarks of cardiac remodeling and are involved functionally in the development of heart failure (HF). However, it is unknown whether Zerumbone (Zer) prevents left ventricular (LV) systolic dysfunction by inhibiting cardiac hypertrophy and fibrosis. PURPOSE: This study investigated the effect of Zer on cardiac hypertrophy and fibrosis in vitro and in vivo. STUDY DESIGN/METHODS: In primary cultured cardiac cells from neonatal rats, the effect of Zer on phenylephrine (PE)-induced hypertrophic responses and transforming growth factor beta (TGF-ß)-induced fibrotic responses was observed. To determine whether Zer prevents the development of pressure overload-induced HF in vivo, a transverse aortic constriction (TAC) mouse model was utilized. Cardiac function was evaluated by echocardiography. The changes of cardiomyocyte surface area were observed using immunofluorescence staining and histological analysis (HE and WGA staining). Collagen synthesis and fibrosis formation were measured by scintillation counter and picrosirius staining, respectively. The total mRNA levels of genes associated with hypertrophy (ANF and BNP) and fibrosis (Postn and α-SMA) were measured by qRT-PCR. The protein expressions (Akt and α-SMA) were assessed by western blotting. RESULTS: Zer significantly suppressed PE-induced increase in cell size, mRNA levels of ANF and BNP, and Akt phosphorylation in cardiomyocytes. The TGF-ß-induced increase in proline incorporation, mRNA levels of Postn and α-SMA, and protein expression of α-SMA were decreased by Zer in cultured cardiac fibroblasts. In the TAC male C57BL/6 mice, echocardiography results demonstrated that Zer improved cardiac function by increasing LV fractional shortening and reducing LV wall thickness compared with the vehicle group. ZER significantly reduced the level of phosphorylated Akt both in cultured cardiomyocytes treated with PE and in the hearts of TAC. Finally, Zer inhibited the pressure overload-induced cardiac hypertrophy and cardiac fibrosis. CONCLUSION: Zer ameliorates pressure overload-induced LV dysfunction, at least in part by suppressing both cardiac hypertrophy and fibrosis.


Assuntos
Cardiomegalia , Remodelação Ventricular , Animais , Cardiomegalia/tratamento farmacológico , Cardiomegalia/patologia , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Miócitos Cardíacos/patologia , Ratos , Sesquiterpenos
5.
Planta Med ; 86(17): 1304-1312, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32645737

RESUMO

Pathological stresses such as pressure overload and myocardial infarction induce cardiac hypertrophy, which increases the risk of heart failure. Cacao bean polyphenols have recently gained considerable attention for their beneficial effects on cardiovascular diseases. This study investigated the effect of cacao bean polyphenols on the development of cardiac hypertrophy and heart failure. Cardiomyocytes from neonatal rats were pre-treated with cacao bean polyphenols and then stimulated with 30 µM phenylephrine. C57BL/6j male mice were subjected to sham or transverse aortic constriction surgery and then orally administered with vehicle or cacao bean polyphenols. Cardiac hypertrophy and function were examined by echocardiography. In cardiomyocytes, cacao bean polyphenols significantly suppressed phenylephrine-induced cardiomyocyte hypertrophy and hypertrophic gene transcription. Extracellular signal-regulated kinase 1/2 and GATA binding protein 4 phosphorylation induced by phenylephrine was inhibited by cacao bean polyphenols treatment in the cardiomyocytes. Cacao bean polyphenols treatment at 1200 mg/kg significantly ameliorated left ventricular posterior wall thickness, fractional shortening, hypertrophic gene transcription, cardiac hypertrophy, cardiac fibrosis, and extracellular signal-regulated kinase 1/2 phosphorylation induced by pressure overload. In conclusion, these findings suggest that cacao bean polyphenols prevent pressure overload-induced cardiac hypertrophy and systolic dysfunction by inhibiting the extracellular signal-regulated kinase 1/2-GATA binding protein 4 pathway in cardiomyocytes. Thus, cacao bean polyphenols may be useful for heart failure therapy in humans.


Assuntos
Cacau , Insuficiência Cardíaca , Animais , Cardiomegalia/tratamento farmacológico , Modelos Animais de Doenças , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hipertrofia Ventricular Esquerda , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos , Polifenóis/farmacologia , Ratos
6.
Biol Pharm Bull ; 43(4): 675-681, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238708

RESUMO

Previous studies have shown that green tea catechins (GTCs) have beneficial effects on obesity and metabolic syndromes. In this study, we prepared kosen-cha from green tea using high pressure extraction, to reduce the astringent taste of the green tea. We identified a large quantity of polymerized GTCs in kosen-cha. To investigate the effects of kosen-cha containing polymerized GTCs in obese Japanese patients, we designed an open-label pilot study in which 6 obese subjects (body mass index (BMI) >25 kg/m2) were administered kosen-cha (5 g/L/d) for 12 weeks. Body composition, serum lipids, insulin resistance, vascular functions, and cardiac hypertrophy were measured before and 12 weeks after kosen-cha administration. Kosen-cha showed no significant adverse effects on the patients. Body weights, BMI, waist circumferences, serum triglyceride (TG) levels, and homeostasis model assessment as an index of insulin resistance (HOMA-IR) levels were significantly decreased after the 12 weeks of administration. Flow-mediated dilation (FMD) (p = 0.0214), brachial-ankle pulse wave velocity (baPWV)(p = 0.0141), left ventricular mass indexes (p = 0.0120), and plasma brain natriuretic peptide (BNP) (p = 0.0144) were significantly improved. Overall, kosen-cha reduced obesity and improved insulin resistance, vascular function, and cardiac hypertrophy, indicating its preventive potential in obesity and metabolic syndrome.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Catequina/farmacologia , Obesidade/dietoterapia , Chá , Adulto , Peso Corporal , Feminino , Alimento Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Risco
7.
Eur Cardiol ; 14(2): 117-122, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31360234

RESUMO

Chronic inflammation plays a significant role in lifestyle-related diseases, such as cardiovascular diseases and obesity/impaired glucose tolerance. Curcumin is a natural extract that possesses numerous physiological properties, as indicated by its anti-inflammatory action. The mechanisms underlying these effects include the inhibition of nuclear factor-kappaB and Toll-like receptor 4-dependent signalling pathways and the activation of a peroxisome proliferator-activated receptor-gamma pathway. However, the bioavailability of curcumin is very low in humans. To resolve this issue, several drug delivery systems have been developed and a number of clinical trials have reported beneficial effects of curcumin in the management of inflammation-related diseases. It is expected that evidence regarding the clinical application of curcumin in lifestyle-related diseases associated with chronic inflammation will accumulate over time.

8.
J Pharmacol Sci ; 136(4): 212-217, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29602708

RESUMO

The natural compound, curcumin (CUR), possesses several pharmacological properties, including p300-specific histone acetyltransferase (HAT) inhibitory activity. In our previous study, we demonstrated that CUR could prevent the development of cardiac hypertrophy by inhibiting p300-HAT activity. Other major curcuminoids isolated from Curcuma longa including demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) are structural analogs of CUR. In present study, we first confirmed the effect of these three curcuminoid analogs on p300-HAT activity and cardiomyocyte hypertrophy. Our results showed that DMC and BDMC inhibited p300-HAT activity and cardiomyocyte hypertrophy to almost the same extent as CUR. As the three compounds have structural differences in methoxy groups at the 3-position of their phenol rings, our results suggest that these methoxy groups are not involved in the inhibitory effects on p300-HAT activity and cardiac hypertrophy. These findings provide useful insights into the structure-activity relationship and biological activity of curcuminoids for p300-HAT activity and cardiomyocyte hypertrophy.


Assuntos
Curcumina/análogos & derivados , Curcumina/farmacologia , Miócitos Cardíacos/patologia , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Animais , Bovinos , Células Cultivadas , Curcuma/química , Curcumina/química , Curcumina/isolamento & purificação , Diarileptanoides , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hipertrofia , Fitoterapia , Coelhos , Relação Estrutura-Atividade
9.
Oncology ; 88(4): 241-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25503567

RESUMO

OBJECTIVE: The aim of this study was to identify the prognostic factors in patients with advanced hepatocellular carcinoma (HCC) who are refractory or intolerant to sorafenib and to exclude unsuitable candidates from subsequent therapy. METHODS: The study cohort consisted of 111 patients who had discontinued sorafenib therapy. Uni- and multivariate analyses were conducted to identify the prognostic factors for survival after discontinuation of sorafenib therapy. RESULTS: The median age of the patients was 70 years, and 96 of them (86%) were male. The Eastern Cooperative Oncology Group performance status was 0-1 in 94 patients (85%). Forty patients (36%) were classified as Child-Pugh class A and 57 (51%) as Child-Pugh class B. The median survival time after discontinuation of sorafenib therapy was 146 days. Hepatitis C viral antibody negativity, presence of ascites, absence of a history of previous treatment excluding sorafenib, elevated serum total bilirubin level, and elevated serum α-fetoprotein level were identified as the independent unfavorable prognostic factors by multivariate analysis. The median survival time of the patients with 4 or 5 unfavorable prognostic factors was 59 days. CONCLUSIONS: We should judge the indication of any subsequent therapy carefully in patients with 4 or 5 of the aforementioned factors.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Niacinamida/uso terapêutico , Prognóstico , Sorafenibe , Taxa de Sobrevida
10.
Cancer Sci ; 105(3): 354-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24438504

RESUMO

The aims of this study were to evaluate the frequency of dose-limiting toxicities and to find the recommended dose of combination chemotherapy with sorafenib and transcatheter arterial infusion (TAI) using cisplatin for patients with advanced hepatocellular carcinoma (HCC), for whom surgical resection, local ablation therapy, or transcatheter arterial chemoembolization were not indicated. Patients received 800 mg sorafenib daily. Cisplatin was given at one of three dosages (level 1, 35 mg/m(2) /cycle; level 2, 50 mg/m(2) /cycle; and level 3, 65 mg/m(2) /cycle) from feeding arteries to the HCC. The treatment was repeated every 4-6 weeks up to a maximum of six cycles, until there were signs of tumor progression or unacceptable toxicity. The dose-limiting toxicities experienced by the 20 enrolled patients were grade 4 increased aspartate aminotransferase at level 1, grade 3 gastrointestinal hemorrhaging at level 1, and grade 3 hypertension at level 3. The common drug-related adverse events that were of severity grade 3 or 4 included the elevation of aspartate aminotransferase (30%), alanine aminotransferase (20%), amylase (30%), and lipase (30%). Partial response was seen in four patients (20%), and 13 patients (65%) had stable disease. The median overall survival and progression-free survival were 9.1 and 3.3 months, respectively. The combination of sorafenib at 800 mg/day with TAI of cisplatin at 65 mg/m(2) /cycle was determined to be the recommended regimen. A randomized phase II trial of sorafenib alone versus sorafenib plus TAI of cisplatin is currently underway. This study was registered at UMIN as trial number UMIN000001496.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Humanos , Infusões Intra-Arteriais , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Sorafenibe , Resultado do Tratamento
11.
J Gastroenterol ; 49(5): 932-40, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23793266

RESUMO

BACKGROUND: The efficacy of sorafenib for hepatocellular carcinoma (HCC) patients refractory to transcatheter arterial chemoembolization (TACE) has not yet been clarified. We investigated the efficacy of sorafenib in HCC patients who were refractory to TACE (sorafenib group) and retrospectively compared the results with those of patients treated with hepatic arterial infusion chemotherapy using cisplatin (cisplatin group). METHODS: We evaluated the anti-tumor effect, the time to progression, and the overall survival in 48 patients in the sorafenib group and 66 patients in the cisplatin group. RESULTS: The disease control rate to sorafenib was 60.4 %, the median time to progression was 3.9 months, and the median survival time was 16.4 months in patients who were refractory to TACE. When compared with the cisplatin group, significant differences in the patient characteristics were not observed between the two groups with the exception of patient age; however, the disease control rate (cisplatin group 28.8 %, P = 0.001), time to progression (cisplatin group: median 2.0 months, hazard ratio 0.44, P < 0.01), and overall survival (cisplatin group: median 8.6 months, hazard ratio 0.57, P < 0.001) were significantly superior in the sorafenib group. The multivariate analysis also showed the sorafenib treatment to be the most significant factor contributing to prolongation of time to progression and overall survival. CONCLUSIONS: Sorafenib showed favorable treatment results in patients refractory to TACE. When compared with hepatic arterial infusion chemotherapy using cisplatin, sorafenib demonstrated a significantly higher disease control rate, a longer time to progression and increased overall survival.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Cisplatino/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Progressão da Doença , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Niacinamida/uso terapêutico , Estudos Retrospectivos , Sorafenibe , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
13.
J Hepatol ; 52(5): 698-704, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20347499

RESUMO

BACKGROUND & AIMS: Bcl-xL, an anti-apoptotic member of the Bcl-2 family, is over-expressed in human hepatocellular carcinoma, conferring a survival advantage to tumour cells. The mechanisms underlying its dysregulation have not been clarified. In the present study, we explored the involvement of microRNAs that act as endogenous sequence-specific suppressors of gene expression. METHODS: The expression profiles of microRNAs in Huh7 hepatoma cells and primary human hepatocytes were compared by microarray analysis. The effect of let-7 on Bcl-xL expression was examined by Western blot and a reporter assay. The involvement of let-7 microRNAs in human tissues was analysed by western blot and reverse transcription-PCR. RESULTS: Microarray analysis, followed by in silico target prediction, identified let-7 microRNAs as being downregulated in Huh7 hepatoma cells in comparison with primary human hepatocytes, as well as possessing a putative target site in the bcl-xl mRNA. Over-expression of let-7c or let-7g led to a clear decrease of Bcl-xL expression in Huh7 and HepG2 cell lines. Reporter assays revealed direct post-transcriptional regulation involving let-7c or let-7g and the 3'-untranslated region of bcl-xl mRNA. Human hepatocellular carcinoma tissues with low expression of let-7c displayed higher expression of Bcl-xL protein than those with high expression of let-7c, suggesting that low let-7 microRNA expression contributes to Bcl-xL over-expression. Finally, expression of let-7c enhanced apoptosis of hepatoma cells upon exposure to sorafenib, which downregulates expression of another anti-apoptotic Bcl-2 protein, Mcl-1. CONCLUSIONS: let-7 microRNAs negatively regulate Bcl-xL expression in human hepatocellular carcinomas and induce apoptosis in cooperation with an anti-cancer drug targeting Mcl-1.


Assuntos
Apoptose/efeitos dos fármacos , Benzenossulfonatos/uso terapêutico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , MicroRNAs/uso terapêutico , Piridinas/uso terapêutico , Proteína bcl-X/genética , Antineoplásicos/uso terapêutico , Sequência de Bases , Benzenossulfonatos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Ciclina G1/genética , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Niacinamida/análogos & derivados , Análise de Sequência com Séries de Oligonucleotídeos , Compostos de Fenilureia , Piridinas/farmacologia , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorafenibe , Estaurosporina/farmacologia , Regulação para Cima/efeitos dos fármacos , Proteína bcl-X/efeitos dos fármacos
14.
J Bacteriol ; 192(1): 127-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19854891

RESUMO

Lumazine protein (LumP) is a fluorescent accessory protein having 6,7-dimethyl-8-(1'-d-ribityl) lumazine (DMRL) as its authentic chromophore. It modulates the emission of bacterial luciferase to shorter wavelengths with increasing luminous strength. To obtain structural information on the native structure as well as the interaction with bacterial luciferase, we have determined the crystal structures of LumP from Photobacterium kishitanii in complexes with DMRL and its analogues, riboflavin (RBF) and flavin mononucleotide (FMN), at resolutions of 2.00, 1.42, and 2.00 A. LumP consists of two beta barrels that have nearly identical folds, the N-terminal and C-terminal barrels. The structures of LumP in complex with all of the chromophores studied are all essentially identical, except around the chromophores. In all of the structures, the chromophore is tethered to the narrow cavity via many hydrogen bonds in the N-terminal domain. These are absent in the C-terminal domain. Hydrogen bonding in LumP-FMN is decreased in comparison with that in LumP-RBF because the phosphate moiety of FMN protrudes out of the narrow cavity. In LumP-DMRL, the side chain of Gln65 is close to the ring system, and a new water molecule that stabilizes the ligand is observed near Ser48. Therefore, DMRL packs more tightly in the ligand-binding site than RBF or FMN. A docking simulation of bacterial luciferase and LumP suggests that the chromophore is located close enough for direct energy transfer to occur. Moreover, the surface potentials around the ligand-binding sites of LumP and bacterial luciferase exhibit complementary charge distributions, which would have a significant effect on the interaction between LumP and luciferase.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Mononucleotídeo de Flavina/química , Proteínas Luminescentes/química , Proteínas Luminescentes/metabolismo , Photobacterium/metabolismo , Pteridinas/química , Riboflavina/química , Cristalografia por Raios X , Mononucleotídeo de Flavina/metabolismo , Dados de Sequência Molecular , Ligação Proteica , Pteridinas/metabolismo , Riboflavina/metabolismo , Difração de Raios X
15.
Hepatol Res ; 37(8): 615-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17517070

RESUMO

AIM: Disorders of protein metabolism in liver cirrhosis can affect prognosis or cause complications. Treatment with branched-chain amino acid (BCAA) and zinc supplements has been shown to be effective against abnormal nitrogen metabolism in liver cirrhosis. There are, however, few studies on the effects of combining these supplements. In this study, the effect of combining BCAA and zinc treatment in cirrhosis was investigated. METHODS: Forty patients with liver cirrhosis who had blood albumin levels of 3.5 g/dL or less and blood zinc levels of 70 mug/dL or less were randomized to receive either BCAA alone or a combination of BCAA and zinc supplements. Blood albumin, the Fischer ratio, and ammonia levels were compared over 5-6 months of treatment. RESULTS: In the combination group, the post/pre treatment change ratio in blood ammonia levels decreased significantly (0.87 +/- 0.26 vs. 1.22 +/- 0.38, P = 0.0033), and the change ratio in the Fischer ratio increased significantly (1.22 +/- 0.29 vs. 1.08 +/- 0.16, P = 0.0165) in comparison with the BCAA monotherapy group. The change ratio in blood albumin levels showed no significant difference between the groups (1.01 +/- 0.07 vs. 1.03 +/- 0.08, P = 0.4646). CONCLUSIONS: More improvement in disorders of nitrogen metabolism in liver cirrhosis occurred after administration of BCAA with zinc than after BCAA alone over 5-6 months of treatment. Further investigation is necessary to determine mechanisms of the action and longer-term clinical efficacy.

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