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1.
Int J Obes (Lond) ; 32(7): 1161-70, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18414417

RESUMO

OBJECTIVE: To investigate the mechanisms underlying the antiobesity effects of a novel isoflavone-free peptide mixture (BSP) derived from black soybean. DESIGN: Long-term effects of BSP were evaluated in diet-induced obese (DIO) mice fed a high-fat (HF) diet without or with BSP (2, 5 or 10% of energy) for 13 weeks, or for 8 weeks in combination with exercise. Acute effects of BSP on food intake and body weight in rats and leptin-deficient ob/ob mice were evaluated. Cell culture models or tissue extracts were used to investigate the mechanisms underlying the antiobesity effect. MEASUREMENT: Total food intake, body weight gain, white adipose tissue (WAT) mass, plasma concentrations of leptin, adiponectin, cholesterol and triglyceride were measured. Janus kinase 2 (JAK2)-dependent signal transducers and activators of the transcription 3 (STAT3) phosphorylation and AMP-activated protein kinase (AMPK) activity were determined using Western-blot in cultured cells or tissue extracts. RESULTS: DIO mice fed an HF diet with BSP (2, 5 or 10%) for 13 weeks gained less body weight (21.4, 19.8 or 17.1 g, respectively) than the mice fed an HF diet without BSP (22.6 g) concurrent with inhibition of total food intake in a dose-dependent manner. BSP also significantly decreased food intake in rats and leptin-deficient ob/ob mice. The highest dose of BSP (10%) significantly elevated the plasma adiponectin and decreased plasma triglyceride. BSP activated JAK2-dependent STAT3 in a cell model, and elevated the level of hypothalamic phospho-STAT3 in ob/ob mice. BSP also phosphorylated AMPK and acetyl-CoA carboxylase of C2C12 myocytes in a dose-dependent manner. The antiobesity effect was augmented by low-intensity wheel-based exercise. In exercised mice, BSP significantly decreased periepididymal WAT mass and body weight gain. CONCLUSION: These results provided evidences that BSP decreased appetite and HF diet-induced body weight gain particularly in combination with exercise, through leptin-like STAT3 phosphorylation and AMPK activation.


Assuntos
Fármacos Antiobesidade/farmacologia , Leptina/metabolismo , Complexos Multienzimáticos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas de Soja/farmacologia , Proteínas Quinases Ativadas por AMP , Tecido Adiposo/metabolismo , Animais , Peso Corporal , Ingestão de Alimentos , Metabolismo Energético , Ativação Enzimática , Feminino , Janus Quinase 2/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Fosforilação , Fator de Transcrição STAT3/metabolismo , Triglicerídeos/sangue
2.
Placenta ; 29(7): 584-92, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18472156

RESUMO

OBJECTIVE: We investigated placental apoptosis and the expression of and interactions between 14-3-3 and Bcl-2 family proteins during preeclampsia. In addition, we explored the mechanism of Bax dissociation from 14-3-3, hypothesizing that PKC-mediated phosphorylation of 14-3-3 results in dissociation of Bax from 14-3-3 proteins, and leads to apoptosis. METHODS: Placental samples from 10 women with preeclampsia and 10 normotensive control patients were analyzed using M30-specific immunohistochemistry to assess placental apoptosis. Biochemical markers of cellular apoptosis, such as cleaved caspase-3, Bax, Bcl-2, 14-3-3, and PKC were followed by Western blotting. Interaction of 14-3-3 proteins with Bax and with PKC was assessed by immunoprecipitation. RESULTS: M30-positive cells were widespread in the preeclamptic placentas. The levels of cleaved caspase-3, Bax, 14-3-3 zeta, phospho-(Ser)-14-3-3, and PKC delta were significantly higher in the preeclamptic placentas than in normal placentas. Preeclampsia was also associated with weaker interactions between 14-3-3 zeta and Bax and stronger interactions between 14-3-3 zeta and PKC delta. CONCLUSION: Our results suggest that PKC delta in preeclamptic placentas promotes Bax dissociation from 14-3-3 zeta through the phosphorylation of 14-3-3 zeta. This finding may at least in part explain the apoptosis-inducing activity of PKC delta, revealing the important role of PKC delta in the development of apoptosis-related diseases such as preeclampsia.


Assuntos
Proteínas 14-3-3/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Proteína Quinase C-delta/fisiologia , Proteína X Associada a bcl-2/metabolismo , Adulto , Apoptose/fisiologia , Feminino , Humanos , Modelos Biológicos , Fosforilação , Placenta/enzimologia , Placenta/patologia , Pré-Eclâmpsia/enzimologia , Pré-Eclâmpsia/patologia , Gravidez , Terceiro Trimestre da Gravidez/metabolismo , Ligação Proteica , Proteína Quinase C-delta/metabolismo
3.
Biochem Pharmacol ; 52(8): 1219-25, 1996 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-8937429

RESUMO

The expression of cytochromes P450 2E1, P450 2B and P450 1A was examined in rat hepatic tissue in response to YH439, an experimental hepatoprotective agent. P450 2E1 metabolic activities relatively specific for P450 2E1 were decreased up to 57% of control activities in the hepatic microsomes prepared from rats treated with YH439 for 3 days. Immunoblot analyses showed that P450 2E1 levels were decreased below the limit of detectability in hepatic microsomes prepared from YH439-treated rats. YH439 at doses from 25 to 100 mg/kg completely suppressed isoniazid-inducible P450 2E1 levels as monitored by both metabolic activities and immunoblot analysis. RNA hybridization analysis revealed that P450 2E1 mRNA levels failed to change after YH439 treatment. These results demonstrate the YH439 effectively suppresses P450 2E1 expression in the absence of transcriptional inactivation. YH439 failed to affect P450 2B1/2 expression, whereas this agent enhanced the hepatic P450 1A1/2 levels. The hepatoprotective effects of YH439 were also examined. Animals treated with CCl4 and ethanol for 9 weeks showed hepatic injury as demonstrated by 2.5- and 2-fold increases in serum alanine aminotransferase and alkaline phosphatase activities, respectively. Concomitant YH439 treatment resulted in a significant protective effect against the experimental hepatic injury. The toxicant-induced elevation in hepatic hydroxyproline level was completely blocked by YH439 treatment. These data indicate that YH439 suppresses the expression of P450 2E1 and protects the liver against chemical-induced hepatic injury and that the selective modulation of detoxifying enzymes by YH439 may contribute to the protection of liver from xenobiotic-induced intoxication.


Assuntos
Citocromo P-450 CYP2E1/genética , Fígado/efeitos dos fármacos , Fígado/enzimologia , Tiazóis/farmacologia , Animais , Sequência de Bases , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/biossíntese , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP2B1/biossíntese , Citocromo P-450 CYP2B1/genética , Citocromo P-450 CYP2E1/biossíntese , Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Fígado/lesões , Masculino , Malonatos/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Sondas de Oligonucleotídeos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
4.
Arch Pharm Res ; 22(2): 202-7, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10230513

RESUMO

New series of catechol ether type derivatives 5, 6 have been synthesized and applied to biological tests. Even though it is a preliminary data, some of our target molecules show the promising result against PDE IV inhibition. SAR and biological studies with synthetic compounds will be discussed in detail.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Inibidores de Fosfodiesterase/síntese química , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Cobaias , Masculino , Inibidores de Fosfodiesterase/farmacologia , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
5.
Placenta ; 35(2): 109-16, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24398013

RESUMO

OBJECTIVE: We investigated the expression of heat shock protein 70 (Hsp70), nuclear factor of activated T cells 5 (NFAT5), and hypoxia-induced factor-1α (HIF-1α) in the placentas of normal and preeclamptic pregnancies and in human placental hypoxia models in vitro to examine the regulatory mechanisms of placental Hsp70 expression. METHODS: The expression levels of HIF-1α, NFAT5, and Hsp70 were examined in placental samples from 10 females with preeclampsia and 10 normotensive control patients and in human choriocarcinoma trophoblast cells treated with 1 mM CoCl2 by western blotting. Using models of placental hypoxia, pharmacological inhibition of HIF-1α with chetomin and shRNA knockdown and overexpression of NFAT5 were performed to investigate the roles of HIF-1α and NFAT5 in induction of Hsp70 by placental hypoxia. RESULTS: The levels of HIF-1α, NFAT5, and Hsp70 expression were significantly higher in the preeclamptic compared to normal placentas. In the placental hypoxia models, the expression of HIF-1α, NFAT5, and Hsp70 were significantly higher after 3, 6, and 12 h of 1 mM CoCl2 treatment, respectively. Pharmacological inhibition of HIF-1α suppressed the induction of NFAT5 and Hsp70 at the protein level. shRNA knockdown of NFAT5 suppressed the induction of Hsp70 protein and overexpression of NFAT5 stimulated the induction of Hsp70 mRNA and protein in models of human placental hypoxia in vitro. CONCLUSION: HIF-1α positively regulates the induction of NFAT5 and Hsp70 by placental hypoxia and NFAT5 stimulates transcription of Hsp70 in response to placental hypoxia in models of human placental hypoxia in vitro.


Assuntos
Proteínas de Choque Térmico HSP70/biossíntese , Hipóxia/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Fatores de Transcrição/biossíntese , Hipóxia Celular , Linhagem Celular Tumoral , Coriocarcinoma/metabolismo , Cobalto , Dissulfetos/farmacologia , Feminino , Técnicas de Silenciamento de Genes , Humanos , Hipóxia/induzido quimicamente , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Técnicas In Vitro , Alcaloides Indólicos/farmacologia , Gravidez , RNA Interferente Pequeno , Fatores de Transcrição/genética
6.
Curr Med Chem ; 18(9): 1380-404, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21366526

RESUMO

The treatment of schizophrenia, one of the most debilitating mental illnesses, began by the serendipitous discovery of chlorpromazine. Since then, researchers have endeavored to find the cause of the illness but it remains unresolved. As a result, literature on the etiology of schizophrenia is littered with hypotheses and theories that are constantly reviewed, modified and rejected. Two hypotheses, however, have withstood the test of time and serve as the basis for the drug treatment, namely the dopamine and serotonin hypotheses. This review introduces the disease state, summarizes in detail the two leading hypotheses on schizophrenia, presents drugs that are currently available for treatment, and discusses some of the promising drug candidates based on their pre and early clinical trial results.


Assuntos
Antipsicóticos/química , Esquizofrenia/tratamento farmacológico , Esquizofrenia/etiologia , Antipsicóticos/uso terapêutico , Encéfalo/patologia , Antagonistas de Dopamina/química , Antagonistas de Dopamina/uso terapêutico , Humanos , Receptores Dopaminérgicos/química , Receptores Dopaminérgicos/metabolismo , Receptores Dopaminérgicos/fisiologia , Receptores de Serotonina/química , Receptores de Serotonina/metabolismo , Receptores de Serotonina/fisiologia , Esquizofrenia/diagnóstico , Antagonistas da Serotonina/química , Antagonistas da Serotonina/uso terapêutico
7.
J Int Med Res ; 39(4): 1497-503, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21986153

RESUMO

This study investigated 151 patients undergoing cardiac surgery to determine whether measurement of regional cerebral oxygen saturation (rS(c)O(2)) using near-infrared spectroscopy (NIRS) can indicate a low haematocrit after initiation of hypothermic cardiopulmonary bypass (CPB). Haematocrit, rS(c)O(2), haemoglobin level, arterial partial pressures of carbon dioxide and oxygen, systemic blood pressure, and nasopharyngeal and rectal temperatures were determined 5 min after the initial administration of heparin for CPB and 90 s after completion of the first cardioplegic solution injection. Immediately after initiation of hypothermic CPB, rS(c)O(2), haemoglobin and haematocrit values were significantly lower than those before CPB. No significant correlations were found between the change in haematocrit and changes in left, right and mean rS(c)O(2); thus, changes in rS(c)O(2) before and after initiation of hypothermic CPB did not reflect changes in haematocrit values. This indicates that NIRS cannot provide early warning of a low haematocrit immediately after initiation of hypothermic CPB in cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Hipotermia , Monitorização Intraoperatória , Espectroscopia de Luz Próxima ao Infravermelho , Pressão Sanguínea , Temperatura Corporal , Feminino , Seguimentos , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Oxigênio/sangue , Prognóstico , Fatores de Risco
8.
Anaesth Intensive Care ; 39(3): 418-25, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21675061

RESUMO

This randomised controlled trial compared the effect of equipotent anaesthetic doses of sevoflurane (S group) versus propofol (P group), during remifentanil-based anaesthesia for off-pump coronary artery bypass surgery, on myocardial injury. Either sevoflurane or propofol was titrated to maintain bispectral index values between 40 and 50. In both groups, a targeted concentration of remifentanil 20 ng x ml(-1) was maintained during anaesthesia. The concentrations of creatine kinase MB and troponin I were measured before the start of surgery, on admission to the intensive care unit, and at 12 and 24 hours after intensive care unit admission. The postoperative values of creatine kinase MB (S group: 15.08 +/- 18.97, 20.78 +/- 20.92, 12.76 +/- 12.82 vs 2.09 +/- 1.54 ng x ml(-1); P group: 10.99 +/- 13.15 27.16 +/- 56.55 11.88 +/- 18.80 vs 1.84 +/- 1.67 ng x ml(-1)) and troponin I (S group: 3.56 +/- 5.19, 566 +/- 7.89, 3.35 +/- 4.55 vs 0.52 +/- 1.90 ng x ml(-1); P group: 2.42 +/- 3.33, 4.11 +/- 6.01, 3.04 +/- 5.31 vs 0.43 +/- 1.28 ng x ml(-1)) were significantly higher than preoperative values in both groups but there were no significant differences between the two groups. There were no significant differences in time to extubation (S group, 476 +/- 284 minutes; P group, 450 +/- 268 minutes) and intensive care unit length of stay (S group, 2775 +/- 1449 minutes; P group, 2797 +/- 1534 minutes) between the two groups. In conclusion, sevoflurane and propofol at equipotent doses guided by bispectral index with remifentanil 20 ng x ml(-1) had similar creatine kinase MB and troponin I values.


Assuntos
Anestésicos/farmacologia , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Coração/efeitos dos fármacos , Éteres Metílicos/farmacologia , Piperidinas/farmacologia , Propofol/farmacologia , Idoso , Creatina Quinase Forma MB/sangue , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Remifentanil , Sevoflurano , Troponina I/sangue
9.
Placenta ; 31(7): 621-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20488538

RESUMO

OBJECTIVE: Although elevated expression of soluble fms-like tyrosine kinase 1 (sFlt1) plays a major role in the pathogenesis of pre-eclampsia, it is unclear how hypoxia regulates placental sFlt1 expression. Thus, we investigated sFlt1 expression in placentas from normal and preeclamptic pregnancies and in human placental hypoxia models in vitro to examine the role of the PI3K-Akt pathway in regulating the expression of this molecule. METHODS: We examined the expression of VEGF, PlGF, sFlt1, PI3K, Akt, and HIF-1 in placental samples from ten women with pre-eclampsia and ten normotensive control patients and in human choriocarcinoma trophoblast cells treated with 600muM CoCl(2) by Western blotting. Using models of placental hypoxia, we also determined whether inhibition of the PI3K-Akt pathway plays a direct role in regulating the expression of sFlt1. RESULTS: The VEGF, PlGF, sFlt1, PI3K, Akt, and HIF-1 levels were significantly higher in the preeclamptic placentas than the normal placentas. In the placental hypoxia models, the expression of VEGF and PlGF increased in a time-dependent manner, whereas the expression of sFlt1 plateaued after 3h of CoCl(2) treatment. The expression levels of p-Akt and PI3K were maximal after 6 and 12h of CoCl(2) treatment, respectively. The expression of HIF-1alpha increased in a time-dependent manner with CoCl(2) treatment. Inhibition of the PI3K-Akt pathway with the PI3K-specific inhibitor LY294002 leads to decreased sFlt1 levels and unchanged or increased VEGF and PlGF levels. CONCLUSION: Inhibition of the PI3K-Akt pathway may be a useful therapeutic approach, if it were to decrease sFlt1 secretion without inhibiting VEGF or PlGF secretion. This pathway provides a potential target for a new treatment strategy in patients with pre-eclampsia.


Assuntos
Hipóxia/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Pré-Eclâmpsia/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromonas/farmacologia , Cobalto/farmacologia , Feminino , Humanos , Hipóxia/induzido quimicamente , Fator 1 Induzível por Hipóxia/biossíntese , Morfolinas/farmacologia , Placenta/metabolismo , Fator de Crescimento Placentário , Gravidez , Proteínas da Gravidez/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
10.
Gene Ther ; 14(3): 191-202, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16957769

RESUMO

We examined the efficacy and host response to the adenovirus (Ad)-mediated delivery of human apolipoprotein A-I (APOA1) gene to the liver of APOA1(-/-) mice. Administration of a first-generation vector (FGAd-AI) resulted in a transient appearance of APOA1 in plasma and induced an anti-APOA1 antibody titer, whereas treatment with a helper-dependent vector (HDAd-AI) resulted in sustained APOA1 expression without inducing an antibody titer. With these results, we studied the effects of FGAd vectors on APOAI expression by HDAd-AI vector. Co-treatment with an FGAd vector inhibited HDAd-AI- mediated APOA1 expression independent of transgene cassettes, but only FGAd-AI induced a humoral response. Furthermore, APOA1 mRNA levels in mice co-treated with FGAd vectors were much lower than those expected from the vector copy number, suggesting that DNA of FGAd vectors interferes with the HDAd-AI vector's APOA1 promoter. A single treatment with an HDAd-AI vector produced a supraphysiological plasma APOA1 level that gradually declined to about half the normal human level over the course of 2 years, associated with a plasma cholesterol level that is persistently higher than that in controls. This investigation provides the proof of principle that liver-directed HDAd gene delivery is effective for the long-term phenotypic correction of monogenic hypoalphalipoproteinemia.


Assuntos
Adenoviridae/genética , Apolipoproteína A-I/genética , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Vírus Auxiliares/genética , Hipoalfalipoproteinemias/terapia , Adenoviridae/imunologia , Animais , Apolipoproteína A-I/análise , Apolipoproteína A-I/imunologia , Autoanticorpos/sangue , Colesterol/sangue , Feminino , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Humanos , Hipoalfalipoproteinemias/imunologia , Hipoalfalipoproteinemias/metabolismo , Injeções , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Fenótipo , Transdução Genética/métodos , Transgenes , Carga Viral
11.
Biopolymers ; 31(2): 177-85, 1991 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-2043748

RESUMO

A high directional Monte Carlo procedure that predicts the topology of the energy hypersurface before it walks, is developed as a method to obtain a global energy minimum structure of polypeptides and proteins. It calculates its covariance matrix, which controls the individual trial step distribution of the next set of steps, from the second moment of the actual walk segment in the previous set. The method is successfully applied to the pentapeptide Metenkephalin system. And it is shown that some initial heating process, which provides the more flexible molecule, is necessary in order to overcome the energy barriers that can be overestimated by some biases in the empirical description of the system. The sampling efficiency, traced by an average conformational changes, is found to be at least 20 times greater than the one in the conventional Metropolis Monte Carlo methods, and it is expected that this increases in efficiency will be more prominent when the system is larger.


Assuntos
Encefalina Metionina/química , Conformação Proteica , Glicina/química , Matemática , Metionina/química , Método de Monte Carlo , Fenilalanina/química , Propriedades de Superfície , Temperatura , Anormalidade Torcional , Tirosina/química
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