Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
1.
J Clin Pharm Ther ; 34(3): 288-99, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19650251

RESUMO

BACKGROUND AND OBJECTIVES: Angiotensin (Ang) II plays an important role in fibrogenesis in various organs, including the lung. The aim of this study is to elucidate (i) the effects of Ang II on the expression of cytokines, growth factors or matrix proteins in normal human lung fibroblasts, and (ii) the inhibitory effects of an Ang II type 1 (AT1) receptor blocker, candesartan. METHODS: Normal human adult lung fibroblasts were cultured. Candesartan was added and the cells were incubated. All the cells in culture dishes were collected at day 0 and 2, and the cell numbers were counted using a Neubauer haemocytometer (Clay-Adams, Parsippany, NJ, USA). The cell proliferation rates at day 2 were calculated in comparison to those at day 0. Total cellular RNA was extracted for real-time quantitative PCR, or the culture supernatant was collected for either a Sircol assay or enzyme-linked immunosorbent assay (ELISA). Laser scanning confocal microscopy was used for analyzing the cells with and without prior exposure to candesartan. Comparisons between the means of multiple groups were analyzed by one-way analysis of variance (ANOVA) followed by Tukey's test or Games-Howell's test. Values of P < 0*05 were considered to be statistically significant. RESULTS: Among the 12 fibrosis-associated cytokines and growth factors, mRNA expressions of interleukin (IL)-4, IL-7, and platelet-derived growth factor-D were significantly modulated by Ang II, and suppressed by candesartan. Soluble collagen and elastin levels were significantly elevated by Ang II, and suppressed by candesartan. Under confocal microscopy, the intracellular distribution of elastin was significantly increased by Ang II, and suppressed by candesartan. CONCLUSION: These data indicate that Ang II promotes lung fibrosis by increasing the matrix formation, which was suppressed by AT1 receptor blocker.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Angiotensina II/metabolismo , Benzimidazóis/farmacologia , Fibroblastos/metabolismo , Tetrazóis/farmacologia , Adulto , Angiotensina II/farmacologia , Compostos de Bifenilo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno/efeitos dos fármacos , Colágeno/metabolismo , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Elastina/efeitos dos fármacos , Elastina/metabolismo , Proteínas da Matriz Extracelular/efeitos dos fármacos , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Microscopia Confocal , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo
2.
Scand J Rheumatol ; 37(5): 360-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18686191

RESUMO

OBJECTIVE: To clarify the clinical characteristics of patients having both anti-U1RNP antibodies (anti-U1RNP) and anti-centromere antibodies (ACA) in comparison to subjects having either anti-U1RNP or ACA alone. SUBJECTS AND METHODS: One hundred and fifty-six subjects who had anti-U1RNP and/or ACA were enrolled. They were classified into three groups: anti-U1RNP alone group (n = 64); ACA alone group (n = 82); and anti-U1RNP+ACA group (n = 10). The anti-U1RNP alone and ACA alone groups were also divided into the low-titre and the high-titre subgroups, respectively. The frequencies of the specific clinical findings and laboratory data were compared among the groups or subgroups. RESULTS: The frequencies of persistent proteinuria or lupus nephritis (LN, 50.0%) and primary biliary cirrhosis (PBC, 30.0%) in the anti-U1RNP+ACA group were higher than that in the anti-U1RNP alone group (17.2%, p<0.01; 3.1%, p = 0.075; respectively). The frequencies of systemic lupus erythematosus (SLE, 60.0%), persistent proteinuria or LN (50.0%), anti-Ro (70.0%), and anti-La (30.0%) in the anti-U1RNP+ACA group were higher than those in the ACA alone group (11.0%, p<0.01; 4.9%, p<0.001; 23.2%, p<0.01; and 6.1%, p = 0.085; respectively). The frequency of systemic sclerosis (SSc) in the high-titre subgroup (30.0%) was higher than that in the low-titre subgroup (11.8%) in the anti-U1RNP alone group, without significance (p = 0.072). The frequency of interstitial pneumonia in the high-titre subgroup (26.8%) was higher than that in the low-titre subgroup (2.4%) in the ACA alone group (p<0.01). CONCLUSIONS: The clinical characteristics of patients with anti-U1RNP+ACA were clarified in comparison to subjects having either anti-U1RNP or ACA alone.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Centrômero/imunologia , Ribonucleoproteína Nuclear Pequena U1/imunologia , Adulto , Idoso , Anticorpos Anti-Idiotípicos/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/imunologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Nefrite Lúpica/sangue , Nefrite Lúpica/imunologia , Masculino , Pessoa de Meia-Idade , Proteinúria/sangue , Proteinúria/imunologia , Escleroderma Sistêmico/sangue , Escleroderma Sistêmico/imunologia
4.
Eur J Surg Oncol ; 33(6): 741-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17399936

RESUMO

AIM: The aim of this study is to evaluate the safety and efficacy of hepatic artery infusion (HAI) of 5-fluorouracil (5FU) for patients with liver metastases from colorectal carcinoma after radiological placement of infusion catheters. METHODS: Forty-two patients with liver metastases from colorectal carcinoma received radiological placement of infusion catheters using the distal fixation method. They received continuous HAI of 5FU 1,000-1,500mg for 5h weekly or biweekly. Tumor status was assessed by chest-abdominal computed tomography (CT) scan after every 10 infusions. Hepatic perfusion was checked by CT arteriography via the infusion port after every 10 infusions. RESULTS: Radiological placements of catheters were performed successfully in all cases. Each patient received an average of 36 treatments (range: 10-98). Catheter failure was found in 3 patients (7.1%). Nine incidents of grade 1 toxicity were observed in 8 patients (19.0%). There was a complete response in 6 patients, partial remission in 18, stable disease in 9, and progression of disease in 9 (response rate: 57.1%). Overall median survival time was 29.1 months. Using Cox's proportional hazard model, lymph node metastases in primary colorectal carcinoma and pre-treatment serum CEA affected overall survival (P=0.011, P=0.005). CONCLUSIONS: HAI after radiological placement of infusion catheters is a safe and effective treatment particularly for patients with no lymph node metastasis in primary carcinoma or with a low pre-treatment serum CEA level.


Assuntos
Carcinoma/secundário , Quimioterapia do Câncer por Perfusão Regional , Neoplasias do Colo/patologia , Artéria Hepática , Neoplasias Hepáticas/secundário , Neoplasias Retais/patologia , Idoso , Angiografia , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/sangue , Carcinoma/tratamento farmacológico , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/instrumentação , Cateteres de Demora/efeitos adversos , Quimioterapia do Câncer por Perfusão Regional/instrumentação , Progressão da Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Humanos , Bombas de Infusão , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Radiografia Intervencionista , Indução de Remissão , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
Arch Virol ; 152(3): 457-61, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17131063

RESUMO

Noroviruses (NoVs) and sapoviruses (SaVs) are causative agents of human gastroenteritis. There is increasing evidence that certain human NoV strains bind to histo-blood group antigens (HBGAs). We found that several NoV virus-like particles (VLPs) showed binding activity to HBGAs, while neither SaV genogroup I (GI) VLP nor SaV GV VLP showed such activity.


Assuntos
Antígenos de Grupos Sanguíneos , Norovirus/fisiologia , Sapovirus/fisiologia , Carboidratos/fisiologia , Gastroenterite/virologia , Humanos , Antígenos do Grupo Sanguíneo de Lewis/fisiologia , Norovirus/classificação , Norovirus/isolamento & purificação , Saliva/virologia , Sapovirus/classificação , Sapovirus/isolamento & purificação
6.
Clin Exp Immunol ; 140(3): 520-3, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15932514

RESUMO

X-linked agammaglobulinaemia (XLA) is an inherited immunodeficiency that is caused by a block in early B-cell differentiation. Whereas early B precursors in the bone marrow are present in substantial numbers, XLA-affected individuals have dramatically reduced numbers of circulating mature B cells, plasma cells and immunoglobulins of all isotypes. We report on a Japanese family with 3 XLA patients, in whom the serum immunoglobulin levels and number of B cells showed a significant difference among them in spite of harbouring the same splice donor site mutation in the BTK gene. We developed concise method for detection of this mutation, which is helpful for discovering the carrier. Patient 2 showed a significant serum immunoglobulin levels of all isotypes, including allergen-specific IgE. Expression of a normal and truncated size BTK gene was detected in patient 2's peripheral blood mononuclear cells (PBMCs). Expression of BTK protein was also detected in some B cells. These results suggest that the leaky phenotype in patient 2 was caused in part by the expression of a normal BTK gene transcript. The increased frequency of infection with age expanded the number of B cells with normal BTK gene expression and produced the serum immunoglobulin, including IgE.


Assuntos
Agamaglobulinemia/genética , Cromossomos Humanos X/genética , Ligação Genética/genética , Adulto , Tirosina Quinase da Agamaglobulinemia , Agamaglobulinemia/imunologia , Linfócitos B/imunologia , Criança , Pré-Escolar , Saúde da Família , Feminino , Expressão Gênica/genética , Humanos , Imunoglobulinas/sangue , Japão , Leucócitos Mononucleares/imunologia , Contagem de Linfócitos/métodos , Masculino , Mutação , Linhagem , Fenótipo , Proteínas Tirosina Quinases/genética
7.
Eur J Drug Metab Pharmacokinet ; 26(3): 185-92, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695719

RESUMO

UNLABELLED: To clarify the dose-response effects of troglitazone on insulin sensitivity and beta-cell function, we examined the effects of high-dose troglitazone (100 mg/day per animal, administered as a food admixture) on glucose and insulin metabolism in hyperinsulinemic Watanabe heritable hyperlipidemic (WHHL) rabbits, and compared the results with our previous results with low-dose troglitazone (10 mg /day per animal). MATERIALS AND METHODS: Glucose and insulin metabolism were quantitatively characterized by a minimal model technique as reported previously. RESULTS: When troglitazone was administrated at a high dose for 6 months, it reduced hyperinsulinemia as reflected by a reduced basal (steady-state) insulin concentration lb and the insulin response to a glucose load, improved beta-cell function as reflected by decreased second-phase post-hepatic insulin delivery to glucose phi2, and reduced insulin resistance as reflected by increased insulin sensitivity to glucose disposal Si, without affecting glucose tolerance as reflected by an unchanged rate of glucose utilization Kg or insulin-independent glucose disposal Sg. The reductions in Ib and phi2 and the increases in Si in WHHL rabbits treated with a high dose of troglitazone were greater (p<0.05) than those observed in WHHL rabbits treated with a low dose of troglitazone, as assessed by a two-way repeated measures analysis of variance and the Wilcoxon-Mann-Whitney test. CONCLUSION: In WHHL rabbits, troglitazone dose-dependently reduced hyperinsulinemia, improved beta-cell function, and increased insulin sensitivity.


Assuntos
Cromanos/farmacologia , Hiperlipidemias/genética , Hiperlipidemias/fisiopatologia , Hipoglicemiantes/farmacologia , Resistência à Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Tiazóis/farmacologia , Tiazolidinedionas , Animais , Glicemia/metabolismo , Cromanos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Teste de Tolerância a Glucose , Hipoglicemiantes/administração & dosagem , Insulina/sangue , Insulina/metabolismo , Modelos Biológicos , Coelhos , Tiazóis/administração & dosagem , Troglitazona
8.
Virus Res ; 73(1): 1-16, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11163640

RESUMO

Recent evidence has accumulated which definitively shows that chemokine receptors CCR5 and CXCR4 play an essential role as coreceptors for human immunodeficiency virus type 1 (HIV-1) infection. Flow cytometric analysis permitted us to detect CD38, a surface marker of early differentiation, as well as activation of T cells, on about half of healthy donor-derived CD4(+) T cells. In this study, we focused on the susceptibility of CD38(+) and CD38(-) subsets of CD4(+) T cells to HIV-1 infection with different coreceptor tropisms. About 20% of peripheral blood mononuclear cell-derived resting CD4(+) T cells were recovered into the CD38(+) subset fraction by panning with a monoclonal antibody to CD38. Most of the cells in this CD38(high) fraction also expressed CD45RA and CD62L at higher intensities compared with those of CD38(low) fraction. CCR5(+) T cells predominated in the CD38(-) subset, although cell surface expression of CD4 and CXCR4 was almost similar between both subsets. This difference was consistent with a significantly higher susceptibility of the CD38(-) subset to a macrophage (M)-tropic HIV-1 strain. In contrast, it was shown that a T-tropic strain of HIV-1 could replicate more efficiently in the CD38(+) subset, although viral adsorption rates were similar between both subsets. Thus, the differential susceptibility of CD4(+) T cells to M(-) and T-tropic HIV-1 was associated with their surface expression of CD38.


Assuntos
Antígenos CD , Antígenos de Diferenciação/análise , Linfócitos T CD4-Positivos/imunologia , HIV-1/patogenicidade , NAD+ Nucleosidase/análise , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Linfócitos T CD4-Positivos/virologia , Células Cultivadas , Citometria de Fluxo , Humanos , Selectina L/análise , Antígenos Comuns de Leucócito/análise , Glicoproteínas de Membrana , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Receptores CCR5/análise , Receptores CXCR4/análise , Subpopulações de Linfócitos T/imunologia , Replicação Viral
9.
Microbiol Mol Biol Rev ; 64(4): 725-45, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104817

RESUMO

In this review we summarize multiple aspects of the human immunodeficiency virus (HIV) protease from both structural and functional viewpoints. After an introductory overview, we provide an up-to-date status report on protease inhibitors (PI). This proceeds from a discussion of PI structural design, to how PI are optimally utilized in highly active antiretroviral triple therapy (one PI along with two reverse transcriptase inhibitors), the emergence of PI resistance, and the natural role of secretory leukocyte PI. Then we switch to another focus: the interaction of HIV protease with other genes in acute and persistent infection, which in turn may have an effect on AIDS pathogenesis. We conclude with a discussion on future directions in HIV treatment, involving multiple-target anti-HIV therapy, vaccine development, and novel reactivation-inhibitory reagents.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/etiologia , Inibidores da Protease de HIV/uso terapêutico , Protease de HIV/efeitos dos fármacos , Vacinas contra a AIDS , Ensaios Clínicos como Assunto , Desenho de Fármacos , Tratamento Farmacológico/tendências , Genes Virais , HIV-1/patogenicidade , Humanos , Latência Viral
10.
Life Sci ; 67(20): 2405-16, 2000 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-11065164

RESUMO

Troglitazone and structurally related compounds (pioglitazone, rosiglitazone etc.) containing thiazolidinediones (TZD) are a novel class of antidiabetic agents which decrease blood glucose in diabetic animal models and in patients with Non-Insulin-Dependent Diabetes Mellitus (NIDDM) through alleviating insulin resistance. A large body of evidence is now accumulating indicating that insulin resistance and/or resulting hyperinsulinemia underlie the pathogenesis of not only diabetes but also of the clustering syndrome called "syndrome X" or "insulin resistance syndrome" which includes hypertension, dislipidemia and hypercoagulation. Therefore, TZD class of insulin sensitizers seem to have therapeutic potential to improve this clustering syndrome in addition to diabetes. Moreover, it was demonstrated that the TZD class of insulin sensitizers including troglitazone bind and activate the peroxisome proliferator-activated receptor gamma (PPARgamma), a nuclear hormone receptor. Although PPARgamma is predominantly expressed in adipose tissue, one of the target tissues for insulin, it have been subsequently found to be expressed in macrophages, vascular smooth muscle cells (VSMC), endothelial cells and several cancer cell lines. PPARgamma activation by PPARgamma agonists such as TZD class of insulin sensitizers in these cells modulates these cell functions such as the production of inflammatory cytokine by macrophages, proliferation and migration of VSMC, and growth or differentiation in cancer cells. In addition, troglitazone has potent antioxidant effect, and suppresses both L-type and receptor operated Ca2+ channel and protein kinase C. Thus since TZD class of insulin sensitizers has many kind of therapeutic effect in addition to lowering blood glucose, these agents expect to have therapeutic potential beyond diabetes.


Assuntos
Cromanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Angina Microvascular/tratamento farmacológico , Tiazóis/uso terapêutico , Tiazolidinedionas , Animais , Antioxidantes/farmacologia , Glicemia/efeitos dos fármacos , Cromanos/metabolismo , Cromanos/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Resistência à Insulina/fisiologia , Masculino , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Tiazóis/metabolismo , Tiazóis/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Troglitazona
11.
Pancreas ; 21(4): 421-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11075998

RESUMO

Abnormality of pancreatic exocrine secretion has been observed in patients with diabetes mellitus. Troglitazone is a novel insulin-sensitizing agent that improves hyperglycemia and hyperinsulinemia in insulin-resistant diabetes mellitus. We investigated the effect of troglitazone on exocrine pancreas in streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by intraperitoneal injection of STZ (25 mg/kg), and then 0.2% troglitazone containing rat chow was given for 2 weeks. Control diabetic animals received normal rat chow for 2 weeks. Glucose tolerance tests were performed before and after the administration of troglitazone. Pancreas weight, enzyme, protein, and insulin contents in the pancreas were measured. For the exocrine secretory study, pure pancreatic juice was collected hourly. Plasma glucose concentrations stimulated by the oral administration of 2.5 g/kg glucose in the troglitazone-treated group were significantly lower than those in the control group, but not plasma insulin concentrations. Pancreas weight in diabetic rats was less than that in normal rats. Administration of troglitazone resulted in a significant increase in pancreas weight and amylase and trypsin output. However, protein and insulin contents were not affected by the treatment with troglitazone. Both basal and cholecystokinin (CCK-8; 26 pmol/kg/h) stimulated exocrine secretion in juice volume, amylase, and trypsin output were markedly decreased in diabetic rats, compared with those in normal rats. Impaired basal and CCK-stimulated pancreatic exocrine secretion in diabetic rats recovered to the normal levels when troglitazone was given. In conclusion, troglitazone might be effective to restore exocrine pancreatic insufficiency in STZ-diabetic rats.


Assuntos
Cromanos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Pâncreas/efeitos dos fármacos , Tiazóis/farmacologia , Tiazolidinedionas , Animais , Colecistocinina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Teste de Tolerância a Glucose , Insulina/análise , Masculino , Pâncreas/química , Pâncreas/metabolismo , Ratos , Ratos Wistar , Estreptozocina , Troglitazona , Fator de Necrose Tumoral alfa/biossíntese
12.
J Med Chem ; 43(16): 3052-66, 2000 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-10956213

RESUMO

A series of imidazopyridine thiazolidine-2,4-diones were designed and synthesized from their corresponding pyridines. These compounds represent conformationally restricted analogues of the novel hypoglycemic compound rosiglitazone (5). The series was evaluated for its effect on insulin-induced 3T3-L1 adipocyte differentiation in vitro and its hypoglycemic activity in the genetically diabetic KK mouse in vivo. The structure-activity relationships are discussed. On the basis of the in vivo potency, 5-[4-(5-methoxy-3-methyl-3H-imidazo[4, 5-b]pyridin-2-ylmethoxy)benzyl]thiazolidine-2,4-dione (19a) was selected as the candidate for further studies in a clinical setting.


Assuntos
Hipoglicemiantes/síntese química , Imidazóis/síntese química , Tiazóis/síntese química , Tiazolidinedionas , Células 3T3 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Animais , Disponibilidade Biológica , Diferenciação Celular , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/genética , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Coração/efeitos dos fármacos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/toxicidade , Imidazóis/química , Imidazóis/farmacologia , Imidazóis/toxicidade , Masculino , Camundongos , Tamanho do Órgão , Ratos , Rosiglitazona , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia , Tiazóis/toxicidade
13.
Prog Drug Res ; 54: 191-212, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10857389

RESUMO

Insulin resistance is characterized as one of the major pathogeneses of type 2 diabetes and has been associated with these same cardiovascular risk factors. Troglitazone, rosiglitazone, and pioglitazone are a new class of oral antidiabetic agents which can ameliorate peripheral insulin resistance in type 2 diabetes. There is considerable evidence that trogliterazone may have beneficial effects on cardiovascular and metabolic abnormalities associated with insulin resistance. There is supportive evidence for positive effects of the other glitazones, but they have been less well studied. These potential benefits span effects ranging from molecular events in the arterial wall to amelioration and/or improvement in lipid parameters known to be associated with atherosclerosis.


Assuntos
Cromanos/farmacologia , Hipoglicemiantes/farmacologia , Tiazóis/farmacologia , Tiazolidinedionas , Animais , Arteriosclerose/prevenção & controle , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Débito Cardíaco/efeitos dos fármacos , Colesterol/sangue , Endotélio Vascular/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Humanos , Lipoproteínas LDL/sangue , Lipoproteínas LDL/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Triglicerídeos/sangue , Troglitazona
15.
Int J Exp Diabetes Res ; 1(3): 195-202, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11467410

RESUMO

Thiazolidinediones (TZD) have been shown to have anti-diabetic effects including the ability to decrease fasting hyperglycemia and hyperinsulinemia, increase insulin-mediated glucose disposal rate (M) and decrease hepatic glucose production, but the mechanisms of action are not well established. To determine whether a TZD (R-102380, Sankyo Company Ltd., Tokyo, Japan) could improve insulin action on skeletal muscle glycogen synthase (GS), the rate-limiting enzyme in glycogen synthesis, 4 insulin-resistant obese monkeys were given 1 mg/kg/day R-102380 p.o. for a 6-week period. Skeletal muscle GS activity and glucose 6-phosphate (G6P) content were compared between pre-dosing and dosing periods before and during the maximal insulin-stimulation of a euglycemic hyperinsulinemic clamp. Compared to pre-dosing, insulin-stimulated GS activity and G6P content were increased by this TZD: GS independent activity (p = 0.02), GS total activity (p = 0.005), GS fractional activity (p = 0.06) and G6P content (p = 0.02). The change in GS activity induced by in vivo insulin (insulin-stimulated minus basal) was also increased by this TZD: GS independent activity (p = 0.03) and GS fractional activity (p = 0.04). We conclude that the TZD R-102380 improves insulin action at the skeletal muscle in part by increasing the activity of glycogen synthase. This improvement in insulin sensitivity may be a key factor in the anti-diabetic effect of the thiazolidinedione class of agents.


Assuntos
Glicogênio Sintase/metabolismo , Hipoglicemiantes/farmacologia , Resistência à Insulina/fisiologia , Insulina/farmacologia , Músculo Esquelético/enzimologia , Obesidade/fisiopatologia , Tiazóis/farmacologia , Tecido Adiposo/anatomia & histologia , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Peso Corporal , Técnica Clamp de Glucose , Glucose-6-Fosfato/metabolismo , Infusões Intravenosas , Insulina/administração & dosagem , Insulina/sangue , Macaca mulatta , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia
16.
Life Sci ; 65(12): 1287-96, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10503944

RESUMO

Recent investigations suggest that cytotoxic cytokines such as tumor necrosis factor (TNF)alpha and interleukin (IL)-1beta or free radicals play an essential role in destruction of pancreatic beta cells in Type 1 diabetes and that, therefore, anti-oxidant or anti-TNF alpha and IL-1beta therapy could prevent the development of Type I diabetes. Troglitazone belongs to a novel class of antidiabetic agent possessing the ability to enhance insulin action provably through activating PPAR gamma and to scavenge free radicals. In the present study, we examined whether troglitazone can prevent the development of Type 1 diabetes in multiple, low-dose streptozotocin (MLDSTZ)-injected mice. In addition, effects of troglitazone on cytokine-induced pancreatic beta cell damage were examined in vitro. Type 1 diabetes was induced by MLDSTZ injection to DBA/2 mice (40 mg/kg/day for 5 days). Troglitazone was administered as a 0.2% food admixture (240 mg/kg/day) for 4 weeks from the start of or immediately after STZ injection. MLDSTZ injection elevated plasma glucose to 615 +/- 8 mg/dl 4 weeks after final STZ injection and was accompanied by infiltration of leukocytes to pancreatic islets (insulitis). Troglitazone treatment with MLDSTZ injection prevented hyperglycemia (230 +/- 30 mg/dl) and, suppressed insulitis and TNF alpha production from intraperitoneal exudate cells. TNF alpha (10 pg/ml) and IL-1beta (1 pg/ml) addition to hamster insulinoma cell line HIT-T15 for 7 days in vitro decreased insulin secretion and cell viability. Simultaneous troglitazone addition (0.03 to approximately 3 microM) significantly improved cytokine-induced decrease in insulin secretion and in cell viability. These findings suggest that troglitazone prevents the development of Type 1 diabetes in the MLDSTZ model by suppressing insulitis associated with decreasing TNF alpha production from intraperitoneal exudate cells and the subsequent TNF alpha and IL-1beta-induced beta cell damage.


Assuntos
Cromanos/uso terapêutico , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Sequestradores de Radicais Livres/uso terapêutico , Hipoglicemiantes/uso terapêutico , Tiazóis/uso terapêutico , Tiazolidinedionas , Animais , Glicemia/análise , Cricetinae , Insulina/sangue , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos DBA , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Estreptozocina , Troglitazona , Fator de Necrose Tumoral alfa/biossíntese
17.
Cell Tissue Res ; 296(2): 359-69, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10382278

RESUMO

Apoptosis of male germ cells is a widespread but little-understood phenomenon in many animal species. The elucidation of its mechanisms could be useful in the understanding of male infertility. We have examined the distribution of dying cells with the terminal transferase-mediated nick-end labeling (TUNEL) method and by an electron-microscopic procedure in the testes of 10 mouse strains, viz., C57BL/10 (B10), SL/NiA (SL), C57BL/6 (B6), C3H/He (C3H), BALB/c (BALB), DBA2 (DBA), CBA/J (CBA), MRL/MpJ(-)+/+ (M+), MRL/MpJ-lpr/lpr (lpr), and wild-type NJL mice (Mus musculus musculus). In the testes of the B10, NJL, SL, B6, C3H, BALB, DBA, and CBA mice, very few TUNEL-positive cells are distributed in the seminiferous tubules, whereas in the testes of the M+ and lpr mice, many TUNEL-positive cells, which are restricted to stage XII seminiferous tubules, have been identified. The most important finding is that many metaphases of meiotic spermatocytes show a marked TUNEL-positive reaction. Some metaphases show apoptotic morphology electron-microscopically. These results suggest that the testes of MRL strains will provide a useful model for the study of the mechanism of metaphase-specific apoptosis in meiotic spermatocytes.


Assuntos
Apoptose , Túbulos Seminíferos/citologia , Espermatócitos/citologia , Testículo/citologia , Animais , Morte Celular , Marcação In Situ das Extremidades Cortadas , Masculino , Metáfase , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Camundongos Endogâmicos , Camundongos Mutantes , Especificidade da Espécie , Espermatócitos/ultraestrutura
18.
Diabetes Care ; 22(6): 908-12, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10372240

RESUMO

OBJECTIVE: Troglitazone was recently reported to specifically promote the differentiation of pre-adipocytes into adipocytes in vitro in subcutaneous fat only, indicating a relation to insulin-resistance-improving action of troglitazone. To expand on this finding, we investigated at the clinical level how long-term administration of troglitazone influences the body fat distribution in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: Troglitazone (400 mg/day) was administered for 6 months to 30 type 2 diabetic patients whose glycemic control was poor. A total of 18 patients received diet therapy alone (in the single-treatment group, BMI 26.0 +/- 4.6, HbA1c 8.2 +/- 1.7%), and 12 patients concomitantly received glibenclamide (1.25-7.5 mg/day) (in the concomitant sulfonylurea group, BMI 25.4 +/- 4.7, HbA1c 9.2 +/- 1.2%). BMI, HbA1c, serum lipid level, and body fat distribution, which were determined by computed tomography (CT) scan at the umbilical level, were measured and compared before and after troglitazone treatment. RESULTS: During the 6-month troglitazone treatment, HbA1c levels decreased and BMI increased in both groups. As for body fat distribution in the single-treatment group, visceral fat area (VFA) decreased (from 118.3 +/- 54.3 to 101.1 +/- 50.8 cm2; P < 0.001), and subcutaneous fat area (SFA) increased (from 189.7 +/- 93.3 to 221.6 +/- 101.6 cm2; P < 0.001), resulting in a decrease in visceral/subcutaneous (V/S) ratio (from 0.74 +/- 0.48 to 0.50 +/- 0.32; P < 0.001). In the concomitant sulfonylurea group, VFA was unchanged (from 108.1 +/- 53.5 to 112.5 +/- 59.9 cm2), while SFA increased (from 144.6 +/- 122.0 to 180.5 +/- 143.5 cm2; P < 0.01), thereby decreasing the V/S ratio (from 0.91 +/- 0.46 to 0.77 +/- 0.44; P < 0.01). The serum triglyceride level and the area under glucose curve during the 75-g oral glucose tolerance test decreased significantly in the single-treatment group. CONCLUSIONS: According to our data, troglitazone appears to promote fat accumulation in the subcutaneous adipose tissue rather than in the visceral adipose tissue in mildly obese Japanese people with type 2 diabetes. This shift of energy accumulation from the visceral to subcutaneous adipose tissue may greatly contribute to the troglitazone-mediated amelioration of insulin resistance.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Cromanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Glibureto/uso terapêutico , Hipoglicemiantes/uso terapêutico , Tiazóis/uso terapêutico , Tiazolidinedionas , Abdome , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/diagnóstico por imagem , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , Quimioterapia Combinada , Feminino , Teste de Tolerância a Glucose , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Pele , Tomografia Computadorizada por Raios X , Troglitazona , Vísceras
19.
Chem Pharm Bull (Tokyo) ; 47(2): 226-40, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10071856

RESUMO

A series of 2-phenylbenzofuran derivatives with a carbamoyl, alkylamino, or alkyloxy group at the 5 or 6 position of the benzofuran ring were synthesized and evaluated for rat and human testosterone 5 alpha-reductase inhibitory activities in vitro. Against rat enzyme, the carbamoyl derivatives had more potent inhibitory activities than the alkylamino or alkyloxy derivatives, and the 6-carbamoyl derivatives tended to be more potent than the 5-carbamoyl derivatives. Against human enzyme, the 6-substituted derivatives had more potent inhibitory activities than the 5-substituted derivatives. The 6-carbamoyl and 6-alkylamino derivatives tended to show stronger inhibitory activities against human type 1 enzyme than against type 2 enzyme, but they were not largely selective.


Assuntos
Inibidores de 5-alfa Redutase , Benzofuranos/síntese química , Inibidores Enzimáticos/síntese química , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/biossíntese , Animais , Benzofuranos/química , Benzofuranos/farmacologia , Células COS , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Masculino , Conformação Molecular , Ratos , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/biossíntese
20.
J Ocul Pharmacol Ther ; 15(1): 73-83, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10048350

RESUMO

Troglitazone is a new antidiabetic drug with a combined chemical structure of thiazolidinedione and alpha-tocopherol like structure (chroman ring). We evaluated the effect oftroglitazone on the morphological and biochemical changes in rat lenses cultured with galactose. Culturing in 30 mM galactose medium for 48 hrs resulted in vacuole formation in the cortex of lens equator (early phase of cataract). A significant amount of galactitol accumulation and lipid peroxide formation were also observed in lenses exposed to galactose. These morphological and biochemical changes associated with galactose were inhibited by 2 or 20 microM troglitazone present in the galactose medium. These results confirm the previous finding that troglitazone delayed the formation of cataract in rats fed a galactose diet. The anticataract effect of troglitazone was discussed in terms of antioxidant property of the drug.


Assuntos
Antioxidantes/farmacologia , Catarata/prevenção & controle , Cromanos/farmacologia , Hipoglicemiantes/farmacologia , Cristalino/efeitos dos fármacos , Tiazóis/farmacologia , Tiazolidinedionas , Aldeído Redutase/metabolismo , Animais , Catarata/induzido quimicamente , Catarata/metabolismo , Catarata/patologia , Galactitol/metabolismo , Galactose , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Cristalino/metabolismo , Cristalino/patologia , Peróxidos Lipídicos/metabolismo , NADP/metabolismo , Técnicas de Cultura de Órgãos , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Troglitazona , Vacúolos/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...