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1.
Diabetes Obes Metab ; 18(3): 249-57, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26661514

RESUMO

AIMS: To examine the efficacy and safety of once-weekly dulaglutide 0.75 mg monotherapy compared with once-daily liraglutide 0.9 mg in Japanese patients with type 2 diabetes (T2D) for 52 weeks. METHODS: We conducted a phase III, randomized, 52-week (26-week primary endpoint), active- and placebo-controlled trial comparing 492 Japanese patients (dulaglutide, n = 281; liraglutide, n = 141; and placebo, n = 70). Participants and investigators were blinded to treatment assignment for dulaglutide and placebo but not for liraglutide (open-label comparator); after 26 weeks, patients randomized to placebo were switched to once-weekly dulaglutide 0.75 mg (open-label). The present paper reports results for patients treated with dulaglutide and patients treated with liraglutide for 52 weeks. RESULTS: At week 52, dulaglutide decreased HbA1c significantly from baseline compared with liraglutide [least squares mean difference: -0.20; 95% confidence interval (CI) -0.39, -0.01; p = 0.04]. At week 52 (last observation carried forward), dulaglutide significantly decreased pre- and post-dinner blood glucose (BG) levels, the mean of seven-point self-monitored BG profiles, the mean of all postprandial BG levels and circadian variation compared with liraglutide. Body weight was generally stable in both groups through 52 weeks. The most frequently reported adverse events were nasopharyngitis, constipation, nausea and diarrhoea. Eight dulaglutide-treated (2.9%) and four liraglutide-treated (2.9%) patients reported hypoglycaemia, with no event being severe. CONCLUSIONS: Monotherapy with once-weekly dulaglutide 0.75 mg was effective and safe in Japanese patients with T2D, with better glycaemic control compared with once-daily liraglutide 0.9 mg.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hemoglobinas Glicadas/efeitos dos fármacos , Hipoglicemiantes/administração & dosagem , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Liraglutida/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Idoso , Glicemia , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Humanos , Hipoglicemia/induzido quimicamente , Japão , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/efeitos dos fármacos , Resultado do Tratamento
2.
Diabetes Obes Metab ; 17(10): 974-83, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26179187

RESUMO

AIMS: To examine the efficacy and safety of once-weekly dulaglutide monotherapy (0.75 mg) compared with placebo and once-daily liraglutide (0.9 mg) in Japanese patients with type 2 diabetes. METHODS: This was a phase III, 52-week (26-week primary endpoint), randomized, double-blind, placebo-controlled, open-label comparator (liraglutide) trial comparing 492 Japanese patients with type 2 diabetes (dulaglutide, n = 281; liraglutide, n = 141; and placebo, n = 70) who were aged ≥20 years. Patients and investigators were blinded to treatment assignment for dulaglutide and placebo but not for liraglutide. The primary objective evaluated the superiority of dulaglutide versus placebo on change from baseline in glycated haemoglobin (HbA1c) at 26 weeks. Analyses were performed on the full analysis set. RESULTS: At 26 weeks, once-weekly dulaglutide was superior to placebo and non-inferior to once-daily liraglutide for HbA1c change from baseline [least squares mean difference: dulaglutide vs placebo -1.57% (95% confidence interval -1.79 to -1.35); dulaglutide vs liraglutide -0.10% (95% confidence interval -0.27 to 0.07)]. The most frequently reported adverse events were nasopharyngitis, constipation, diarrhoea, nausea, abdominal distension and decreased appetite; only decreased appetite was different between the dulaglutide and liraglutide groups [dulaglutide, n = 2 (0.7%); liraglutide, n = 8 (5.8%); p = 0.003]. Nine (1.8%) patients experienced hypoglycaemia [dulaglutide, n = 6 (2.1%); liraglutide, n = 2 (1.5%); placebo, n = 1 (1.4%)], with no event being severe. CONCLUSIONS: In Japanese patients with type 2 diabetes, once-weekly dulaglutide (0.75 mg) was superior to placebo and non-inferior to once-daily liraglutide (0.9 mg) for reduction in HbA1c at 26 weeks. Dulaglutide was safe and well tolerated.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes/administração & dosagem , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Liraglutida/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Idoso , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Japão , Liraglutida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/efeitos adversos
3.
J Int Med Res ; 37(6): 1904-12, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20146890

RESUMO

This study investigated the effects of mitiglinide in 16 patients with type 2 diabetes mellitus treated with 30 mg/day mitiglinide, divided into three doses given just before each meal, for approximately 12 months. A 450 kcal meal tolerance test was performed at baseline and after 3, 6 and 12 months, and levels of plasma glucose and immunoreactive insulin were measured. Various parameters of glucose metabolism and lipid metabolism, urinary albumin and markers of atherosclerosis, coagulation and fibrinolysis were also determined. Mitiglinide showed a rapid stimulatory effect on insulin secretion and reduced the levels of plasma glucose. The free fatty acid level significantly decreased at 60 min after the meal tolerance test. Mitiglinide also significantly lowered glycosylated haemoglobin and raised 1,5-anhydroglucitol after 6 months, and significantly decreased urinary albumin after 12 months. These data indicate that mitiglinide may have beneficial effects not only on glycaemic control but also on lipid metabolism and urinary albumin excretion, and may have a role in the prevention of the vascular complications of diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Isoindóis/uso terapêutico , Albuminúria/complicações , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Desoxiglucose/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Jejum/sangue , Ácidos Graxos/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Isoindóis/farmacologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/efeitos dos fármacos , Análise de Regressão
4.
Diabetologia ; 50(9): 1900-1909, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17632702

RESUMO

AIMS/HYPOTHESIS: We examined the effect of glucagon-like peptide-1 (GLP-1) on the development of diabetes and islet morphology in NOD mice by administering GLP-1 to prediabetic mice. METHODS: Eight-week-old female NOD mice were infused subcutaneously with human GLP-1 via a mini-osmotic pump for 4 or 8 weeks. In mice treated with GLP-1 for 4 weeks, blood glucose levels and body weight were measured. An intraperitoneal glucose tolerance test (IPGTT) and evaluation of insulitis score were also performed. Beta cell area, proliferation, apoptosis, neogenesis from ducts and subcellular localisation of forkhead box O1 (FOXO1) were examined by histomorphometrical, BrdU-labelling, TUNEL, insulin/cytokeratin and FOXO1/insulin double-immunostaining methods, respectively. RESULTS: Mice treated with human GLP-1 for 4 weeks had lower blood glucose levels until 2 weeks after completion of treatment, showing improved IPGTT data and insulitis score. This effect continued even after cessation of the treatment. In addition to the increase of beta cell neogenesis, BrdU labelling index was elevated (0.24 vs 0.13%, p < 0.001), while apoptosis was suppressed by 54.2% (p < 0.001) in beta cells. Beta cell area was increased in parallel with the translocation of FOXO1 from the nucleus to the cytoplasm. The onset of diabetes was delayed in mice treated with GLP-1 for 4 weeks, while mice treated with GLP-1 for 8 weeks did not develop diabetes by age 21 weeks compared with a 60% diabetes incidence in control mice at this age. CONCLUSIONS/INTERPRETATION: Continuous infusion of human GLP-1 to prediabetic NOD mice not only induces beta cell proliferation and neogenesis, but also suppresses beta cell apoptosis and delays the onset of type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/prevenção & controle , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Fragmentos de Peptídeos/fisiologia , Animais , Glicemia/metabolismo , Divisão Celular , Diabetes Mellitus Tipo 1/patologia , Feminino , Teste de Tolerância a Glucose , Humanos , Imuno-Histoquímica , Células Secretoras de Insulina/citologia , Camundongos , Camundongos Endogâmicos NOD , Pâncreas/patologia
5.
Diabetologia ; 50(3): 596-601, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17221211

RESUMO

AIMS/HYPOTHESIS: Type 1A diabetes results from autoimmune destruction of pancreatic beta cells. We examined the involvement of TNF-alpha and IL-1beta, as well as of T cells, macrophages and dendritic cells, in the destruction of beta cells in patients with recent-onset type 1 diabetes. MATERIALS AND METHODS: We obtained pancreatic biopsy specimens from six patients with recent-onset type 1 diabetes and analysed these by immunohistochemistry. RESULTS: T cell infiltration was less common in islets without beta cells (12.5 [0-33.3]%) than in those with beta cells (46.0 [17.4-83.3]%), while macrophages and dendritic cells showed a similar extent of infiltration into islets both with or without beta cells. TNF-alpha was detected in 25.0 (4.3-46.9)% of macrophages and 11.8 (0-40.0)% of dendritic cells infiltrating the islets in samples from each patient, but not at all in T cells. IL-1beta was detected in 1.8 (0-11.3)% of T cells infiltrating the islets with beta cells, while it was found in 19.2 (0-35.3)% of macrophages or 10.7 (0-31.3)% of dendritic cells infiltrating the islets in samples from each patient (all values median [range]). CONCLUSIONS/INTERPRETATION: Macrophages and dendritic cells infiltrate the islets and produce inflammatory cytokines (TNF-alpha and IL-1beta) during the development of type 1A diabetes.


Assuntos
Células Dendríticas/patologia , Diabetes Mellitus Tipo 1/genética , Ilhotas Pancreáticas/fisiopatologia , Macrófagos/patologia , Fator de Necrose Tumoral alfa/biossíntese , Adolescente , Adulto , Antígenos CD/análise , Feminino , Humanos , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/patologia , Masculino , Fator de Necrose Tumoral alfa/sangue
6.
Diabetologia ; 48(8): 1560-4, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15991022

RESUMO

AIMS/HYPOTHESIS: We have previously reported that fulminant type 1 diabetes is characterised by an absence of diabetes-related antibodies and a remarkably abrupt onset. However, little is known about the mechanism of beta cell destruction in this diabetes subtype, and to obtain insights into the aetiology of the disease, we investigated residual endocrine cells and the expression of Fas and Fas ligand in fulminant type 1 diabetes. METHODS: Residual beta and alpha cells were morphologically assessed in pancreatic tissue obtained by biopsy from five patients with recent-onset fulminant type 1 diabetes and five patients with recent-onset typical autoimmune type 1 diabetes. In addition, the expression of Fas and Fas ligand was evaluated by immunohistochemistry. RESULTS: In fulminant type 1 diabetes, beta and alpha cell areas were decreased significantly, compared with autoimmune type 1 diabetes and control subjects. In contrast, the alpha cell area was not decreased significantly in autoimmune type 1 diabetes, compared with that in control subjects. No Fas expression in islets and Fas ligand expression in CD3(+) cells in the exocrine pancreas were found in the fulminant type 1 diabetic patients who underwent this evaluation. CONCLUSIONS/INTERPRETATION: Our study showed that beta and alpha cells are damaged in fulminant type 1 diabetes. In addition to the lack of Fas and Fas ligand expression, the results suggest that the mechanism of beta cell destruction in fulminant type 1 diabetes is different from that in autoimmune type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/patologia , Ilhotas Pancreáticas/patologia , Acidose/metabolismo , Adulto , Proteína Ligante Fas , Feminino , Humanos , Imuno-Histoquímica , Ilhotas Pancreáticas/metabolismo , Cetoácidos/metabolismo , Cetose/metabolismo , Masculino , Glicoproteínas de Membrana/biossíntese , Pâncreas Exócrino/metabolismo , Receptor fas/biossíntese
7.
Gut ; 54(6): 789-96, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15888786

RESUMO

BACKGROUND AND AIMS: A characteristic feature of Crohn's disease (CD) is mesenteric adipose tissue hypertrophy. Mesenteric adipocytes or specific proteins secreted by them may play a role in the pathogenesis of CD. We recently identified adiponectin as an adipocyte specific protein with anti-inflammatory properties. Here we report on expression of adiponectin in mesenteric adipose tissue of CD patients. METHODS AND RESULTS: Mesenteric adipose tissue specimens were obtained from patients with CD (n = 22), ulcerative colitis (UC) (n = 8) and, for controls, colon carcinoma patients (n = 28) who underwent intestinal resection. Adiponectin concentrations were determined by enzyme linked immunosorbent assay, and adiponectin mRNA levels were determined by real time quantitative reverse transcription-polymerase chain reaction. Tissue concentrations and release of adiponectin were significantly increased in hypertrophied mesenteric adipose tissue of CD patients compared with normal mesenteric adipose tissue of CD patients (p = 0.002, p = 0.040, respectively), UC patients (p = 0.002, p = 0.003), and controls (p<0.0001, p<0.0001). Adiponectin mRNA levels were significantly higher in hypertrophied mesenteric adipose tissue of CD patients than in paired normal mesenteric adipose tissue from the same subjects (p = 0.024). Adiponectin concentrations in hypertrophied mesenteric adipose tissue of CD patients with an internal fistula were significantly lower than those of CD patients without an internal fistula (p = 0.003). CONCLUSIONS: Our results suggest that adipocytes in hypertrophied mesenteric adipose tissue produce and secrete significant amounts of adiponectin, which could be involved in the regulation of intestinal inflammation associated with CD.


Assuntos
Tecido Adiposo/metabolismo , Doença de Crohn/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mesentério/metabolismo , Adipócitos/metabolismo , Adipócitos/patologia , Adiponectina , Tecido Adiposo/patologia , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Doença de Crohn/patologia , Feminino , Humanos , Hipertrofia , Interleucina-6/metabolismo , Masculino , Mesentério/patologia , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo
8.
Diabetologia ; 48(2): 290-3, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15654603

RESUMO

AIMS/HYPOTHESIS: We have recently proposed that fulminant type-1 diabetes is a novel subtype of type-1 diabetes with abrupt onset of insulin-deficient hyperglycaemia without islet-related autoantibodies. The pathogenesis is still unknown, but flu-like symptoms are frequently observed before the onset of disease of this subtype. Enterovirus infection is a candidate environmental factor causing type-1 diabetes. The aim of this study was to determine whether enterovirus infection contributes to the development of fulminant type-1 diabetes. METHODS: We investigated 19 patients with recent-onset fulminant type-1 diabetes, 18 patients with recent-onset typical type-1A diabetes, and 19 healthy controls. IgM, IgG, and IgA subclasses of antibodies to enterovirus were determined by ELISA. RESULTS: IgA antibody titres to enterovirus were significantly higher in fulminant type-1 diabetes than in typical type-1A diabetes (p=0.033) and controls (p=0.0003). IgM antibodies to enterovirus were not detected in any subject. IgG titres were lower in autoimmune diabetes than fulminant type and controls (p=0.014 and 0.019, respectively). CONCLUSIONS/INTERPRETATION: High titres of enterovirus IgA antibodies in serum suggest recurrent enterovirus infection in fulminant type-1 diabetic patients, indicating higher susceptibility to enteroviral infections among them. Such infections might have pathogenetic importance in the triggering of fulminant type-1 diabetes.


Assuntos
Anticorpos Antivirais/sangue , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/virologia , Infecções por Enterovirus/imunologia , Imunoglobulina A/sangue , Adulto , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Cetoacidose Diabética/sangue , Cetoacidose Diabética/imunologia , Cetoacidose Diabética/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Hemoglobinas Glicadas/análise , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Valores de Referência
9.
Diabetologia ; 47(7): 1285-1291, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15243701

RESUMO

AIMS/HYPOTHESIS: Fulminant Type 1 diabetes is a novel subtype of Type 1 diabetes that involves the abrupt onset of insulin-deficient hyperglycaemia. This subtype appears to be non-autoimmune because of the absence of diabetes-related autoantibodies in the serum, and of insulitis in pancreatic biopsy specimens. The pathogenesis of the disease is still unknown. In this study, we investigated whether T cell autoimmune responses are involved in fulminant Type 1 diabetes. METHODS: Cellular immune responses to beta cell autoantigens were studied by enzyme-linked immunospot (ELISPOT) assay in 13 fulminant Type 1 diabetic patients and 49 autoantibody-positive autoimmune Type 1 diabetic patients. Results were compared with those of 18 Type 2 diabetic patients, six secondary diabetic patients (diabetes due to chronic pancreatitis) and 35 healthy controls. RESULTS: Nine of 13 (69.2%) GAD-reactive Th1 cells, and three of 12 (25%) insulin-B9-23-reactive Th1 cells were identified in fulminant Type 1 diabetic patients by ELISPOT, as in autoantibody-positive Type 1 diabetic patients. Four fulminant Type 1 diabetic patients possessed the highly diabetes-resistant allele DR2, three of whom had GAD-reactive Th1 cells in the periphery. CONCLUSIONS/INTERPRETATION: Peripheral immune reaction was observed in 69.2% of fulminant Type 1 diabetic patients, indicating that autoreactive T cells might contribute, at least in part, to the development of fulminant Type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Ilhotas Pancreáticas/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Autoanticorpos/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Hemoglobinas Glicadas/análise , Teste de Histocompatibilidade , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade
10.
Horm Metab Res ; 35(9): 537-40, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14517770

RESUMO

Adiponectin is a plasma protein exclusively secreted by adipose tissue, which plays a role in modulating lipid and glucose metabolism. The plasma adiponectin concentration shows an inverse correlation with the body mass index in normal and obese individuals, but it has not been investigated in subjects with an extremely low body weight and undernutrition such as anorexia nervosa patients. We investigated plasma adiponectin levels in 21 females with anorexia nervosa. Nineteen healthy females served as the lean control group. The subjects with anorexia nervosa had a significantly lower weight and showed a tendency towards higher adiponectin levels than the control group. No correlation between adiponectin and BMI was found in patients with anorexia nervosa, while a linear negative correlation was seen in lean controls. The patient who showed the lowest adiponectin level reached a life-threatening state and required intravenous feeding in hospital. In association with improved nutrition and weight gain, the adiponectin level increased gradually until the body mass index was about 16 and then decreased subsequently as would be expected in lean normal subjects. These observations suggest that adipose tissue secretes less adiponectin and the adiponectin levels do not show an inverse correlation simply with body mass index in some subjects with severe undernutrition.


Assuntos
Tecido Adiposo/metabolismo , Anorexia Nervosa/sangue , Índice de Massa Corporal , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas/metabolismo , Adiponectina , Adolescente , Adulto , Feminino , Humanos , Plasma/química , Proteínas/análise , Valores de Referência
11.
Horm Metab Res ; 35(5): 308-12, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12916001

RESUMO

Phospho enolpyruvate carboxykinase (PEPCK) plays an important role in gluconeogenesis and hepatic glucose production. To test the hypothesis that mutations of the PEPCK gene promoter contribute to the increased hepatic glucose production that leads to diabetes, we screened for polymorphisms of the PEPCK promoter region in 252 Japanese type 2 diabetic patients and 188 non-diabetic control subjects. A novel variant at position - 232 (C to G) was found at a similar frequency in type 2 diabetes patients (32 %) and control subjects (35 %) (p = 0.26). However, patients with the - 232 G/G genotype had an earlier age of onset than those with the - 232 C/C or - 232 C/G genotypes (p = 0.028). As the variant might well otherwise influence hormonal action, we transfected PEPCK-luciferase fusion gene constructs with the variant into human hepatoma cells and examined the response to dexamethasone, insulin, and cAMP. The reporter assay showed no significant difference in hormonal responses with the fusion gene containing the variant. Accordingly, the single-base variant at position - 232 of the PEPCK gene promoter is most probably not a major contributor to the pathogenesis of type 2 diabetes. However, this variation may be useful as a genetic marker for other metabolic disorders, especially in Japanese.


Assuntos
Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Regiões Promotoras Genéticas/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Anti-Inflamatórios/farmacologia , Células Cultivadas , Dexametasona/farmacologia , Feminino , Humanos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Japão , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
12.
Diabetologia ; 46(4): 567-73, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12669197

RESUMO

AIMS/HYPOTHESIS: Mutations in hepatocyte nuclear factor (HNF)-4alpha gene cause a form of maturity-onset diabetes of the young (MODY1). The T130I mutation is a rare missense mutation, which affects a conserved amino acid in a DNA binding domain. This mutation can be found in the general population, so this variant alone does not cause MODY. However, its significance in the development of late-onset Type 2 diabetes is not known. METHODS: We screened 423 unrelated Japanese patients with late-onset Type 2 diabetes and 354 unrelated non-diabetic control subjects for the T130I mutation in the HNF-4alpha gene. The transactivation ability of T130I-HNF-4alpha was assessed using reporter gene assay. RESULTS: The frequency of the T130I mutation was higher in Type 2 diabetic patients ( p=0.015, odds ratio 4.3, 95%CI 1.24-14.98) than control subjects. The serum HDL-cholesterol concentration was lower in Type 2 diabetic patients with the T130I mutation compared with those without this mutation ( p=0.006). Reporter gene analysis showed that T130I-HNF-4alpha transcriptional activity was not impaired compared with wild-type HNF-4alpha in Hela and MIN6 cells, but it was reduced in HepG2 and primary cultured mouse hepatocytes (27-78% of wild type, p<0.05). CONCLUSION/INTERPRETATION: Our findings suggest that T130I-HNF-4alpha is a loss-of-function mutation in hepatocytes and that this mutation is associated with late-onset Type 2 diabetes in Japanese subjects. The T130I mutation in the HNF-4alpha gene might be involved in the development of Type 2 diabetes in the Japanese population.


Assuntos
Povo Asiático/genética , Proteínas de Ligação a DNA , Diabetes Mellitus Tipo 2/genética , Fosfoproteínas/genética , Fosfoproteínas/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Idade de Início , Idoso , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Feminino , Testes Genéticos , Fator 4 Nuclear de Hepatócito , Humanos , Japão , Masculino , Mutação de Sentido Incorreto/genética , Mutação de Sentido Incorreto/fisiologia
13.
Diabetologia ; 45(8): 1142-53, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12189445

RESUMO

AIMS/HYPOTHESIS: One subtype of MODY (MODY3) results from the heterozygous mutation of a hepatocyte nuclear factor (HNF)-1alpha. The pattern of HNF-1alpha expression in the normal pancreas has not been determined. This study aimed to clarify the profile of HNF-1alpha protein expression in the developing mouse pancreas. METHODS: Double immunofluorescence staining was carried out for HNF-1alpha and pancreatic hormones or transcription factors (PDX-1, Pax6, Isl1, and Nkx2.2). The expression of these transcription factors was also studied in the beta cells of HNF-1 alpha mutant mice. RESULTS: HNF-1alpha was expressed by both endocrine and exocrine cells of the pancreas. Double immunofluorescence staining showed that HNF-1alpha was expressed in the nuclei of alpha cells, beta cells, delta cells, and pancreatic polypeptide (PP) cells. HNF-1alpha was first detected in most pancreatic epithelial cells on embryonic day 10.5 (E10.5), and hormone-positive endocrine cells and amylase-positive cells expressed HNF-1alpha on E15.5. Most of the Pax6-, Isl1-, or PDX-1-positive cells showed co-expression of HNF-1alpha. However, HNF-1alpha immunoreactivity was not observed in 36.0% of Nkx2.2-positive cells. Expression of Nkx2.2, Isl1 and Pax6 seemed to be normal in the beta cells of transgenic mice with dominant negative overexpression of HNF-1alpha. Expression of PDX-1 did not change in the beta cells of pre-diabetic HNF-1 alpha (-/-) mice, but expression was markedly decreased in the diabetic stage. CONCLUSION/INTERPRETATION: HNF-1alpha is expressed by both endocrine cells and exocrine cells of the pancreas from the foetal stage along with other transcription factors, so HNF-1alpha might play a role during development.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/metabolismo , Proteínas de Ligação a DNA , Feto/fisiologia , Proteínas Nucleares , Pâncreas/embriologia , Pâncreas/metabolismo , Fatores de Transcrição/metabolismo , Envelhecimento/metabolismo , Animais , Western Blotting , Células COS , Desenvolvimento Embrionário e Fetal , Fator 1 Nuclear de Hepatócito , Fator 1-alfa Nuclear de Hepatócito , Fator 1-beta Nuclear de Hepatócito , Proteína Homeobox Nkx-2.2 , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Fatores de Transcrição/genética
15.
Atherosclerosis ; 159(1): 67-75, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11689208

RESUMO

Reverse cholesterol transport (RCT) is the major protective system against atherosclerosis. In this system, cholesteryl ester transfer protein (CETP) is known to facilitate the transfer of neutral lipids between lipoproteins in plasma. We reported the pathophysiological significance of CETP by clinical studies with genetic CETP deficiency, showing that this protein plays a crucial role in the RCT system. However, information about the expression of this protein in the initial step of RCT, macrophages (Mphi) in the blood vessels, is still very limited. In the present study, we have performed immunohistochemical analyses on the expression of CETP in human atherosclerotic lesions. The immunoreactive mass of CETP was abundantly detected in foam cells in human aortic and coronary atherosclerotic lesions, but not in the normal arterial wall. A double immunostaining showed that the majority of CETP-positive foam cells were derived from Mphi and a minor population appeared to derive from smooth muscle cells. Transient transfection of CETP cDNA into COS-7 cells showed that high density lipoprotein (HDL)-mediated efflux of free cholesterol from the cells expressing CETP was much higher than that from mock-transfected cells, while uptake of HDL-lipids was not affected in cells transfected with CETP cDNA. Efflux of free cholesterol from the Mphi obtained from CETP deficiency was significantly decreased compared with that from normal subjects. These data indicate that CETP is expressed in Mphi in the atherosclerotic lesions and may possess an anti-atherogenic function to remove cholesterol from the cells, suggesting another role of CETP at the initial step of RCT.


Assuntos
Arteriosclerose/metabolismo , Proteínas de Transporte/metabolismo , Colesterol/metabolismo , Glicoproteínas , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Aorta/metabolismo , Arteriosclerose/patologia , Transporte Biológico , Células COS , Proteínas de Transporte/análise , Proteínas de Transporte/genética , Células Cultivadas , Proteínas de Transferência de Ésteres de Colesterol , Vasos Coronários/metabolismo , Células Espumosas/metabolismo , Humanos , Imuno-Histoquímica , Lipoproteínas HDL/metabolismo , Macrófagos/metabolismo , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Transfecção
16.
Nucleic Acids Res ; 29(17): 3506-12, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11522819

RESUMO

We have purified GST-fused recombinant mouse Dnmt3a and three isoforms of mouse Dnmt3b to near homogeneity. Dnmt3b3, an isoform of Dnmt3b, did not have DNA methylation activity. Dnmt3a, Dnmt3b1 or Dnmt3b2 showed similar activity toward poly(dG-dC)-poly(dG-dC) for measuring de novo methylation activity, and toward poly(dI-dC)-poly(dI-dC) for measuring total activity. This indicates that the enzymes are de novo-type DNA methyltransferases. The enzyme activity was inhibited by NaCl or KCl at concentrations >100 mM. The kinetic parameter, K(m)(AdoMet), for Dnmt3a, Dnmt3b1 and Dnmt3b2 was 0.4, 1.2 and 0.9 microM when poly(dI-dC)-poly(dI-dC) was used, and 0.3, 1.2 and 0.8 microM when poly(dG-dC)-poly(dG-dC) was used, respectively. The K(m)(DNA) values for Dnmt3a, Dnmt3b1 and Dnmt3b2 were 2.7, 1.3 and 1.5 microM when poly(dI-dC)-poly(dI-dC) was used, and 3.5, 1.0 and 0.9 microM when poly(dG-dC)-poly(dG-dC) was used, respectively. For the methylation specificity, Dnmt3a significantly methylated CpG >> CpA. On the other hand, Dnmt3b1 methylated CpG > CpT >/= CpA. Immuno-purified Dnmt3a, Myc-tagged and overexpressed in HEK 293T cells, methylated CpG >> CpA > CpT. Neither Dnmt3a nor Dnmt3b1 methylated the first cytosine of CpC.


Assuntos
DNA (Citosina-5-)-Metiltransferases/metabolismo , Sítios de Ligação/genética , Linhagem Celular , DNA/genética , DNA/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/efeitos dos fármacos , DNA Metiltransferase 3A , Relação Dose-Resposta a Droga , Escherichia coli/genética , Expressão Gênica , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Cinética , Cloreto de Potássio/farmacologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , S-Adenosilmetionina/farmacologia , Cloreto de Sódio/farmacologia , DNA Metiltransferase 3B
17.
Atherosclerosis ; 156(2): 297-305, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11395025

RESUMO

CD36 and scavenger receptor class A types I and II (SR-AI/II) are major receptors for oxidized low density lipoproteins (OxLDL) expressed on macrophages. To elucidate the role of these two macrophage scavenger receptors in the development of coronary atherosclerosis, we examined the localization of CD36 and SR-AI/II in human coronary atherosclerotic lesions. Serial cryostat sections of 49 coronary arteries obtained from 43 autopsied cases were examined immunohistochemically. Regarding the relationship between the severity of atherosclerosis and immunoreactivities to CD36, there was almost no immunoreactivity to CD36 in regions with diffuse intimal thickening, while the expression of CD36 was accelerated in parallel with the progression of atherosclerosis. In contrast, SR-AI/II was expressed persistently from regions with diffuse intimal thickening to atherosclerotic plaques. We also clarified the differential distribution of CD36 and SR-AI/II in atheromatous plaques. Close to the luminal surface of the intima, macrophages were relatively small in size, contained lesser lipids, and expressed SR-AI/II more abundantly than CD36. In contrast, macrophages in the core region were larger in size, contained more lipids, were strongly positive for CD36 and showed a weaker immunoreactivity to SR-AI/II than those in the luminal surface of the intima. In conclusion, the expression of CD36 and SR-AI/II on macrophages may be regulated differently in the process of coronary atherogenesis.


Assuntos
Antígenos CD36/análise , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Vasos Coronários/metabolismo , Proteínas de Membrana , Receptores Imunológicos/análise , Receptores de Lipoproteínas , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Vasos Coronários/imunologia , Vasos Coronários/patologia , Técnicas de Cultura , Feminino , Humanos , Imuno-Histoquímica , Lactente , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Receptores Depuradores , Receptores Depuradores Classe A , Receptores Depuradores Classe B , Sensibilidade e Especificidade , Índice de Gravidade de Doença
18.
Diabetes ; 50(6): 1269-73, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375326

RESUMO

To better understand the pathogenesis of type 1 diabetes, we have developed pancreatic biopsy under laparoscope for recent-onset type 1 diabetic patients. The patients included 29 acute-onset type 1 diabetic patients, 5 latent-onset type 1 diabetic patients, and 1 type 2 diabetic patient. Their median age was 28 years, and the duration of diabetes at the time of biopsy was approximately 3 months. In 31 of 35 patients, we could obtain the pancreas tissue by punching. No serious complications, such as heavy bleeding, peritonitis, or pancreatitis, have been experienced. Pneumoderma was observed in two patients, and abdominal dull pain had continued for 2 days in two patients. However, special treatment was not necessary for these complications. T-cell-predominant infiltration to islets (insulitis) and hyperexpression of major histocompatibility complex class I antigens on islet cells were the two major findings and were observed in 17 of 29 recent-onset type 1 diabetic patients. These findings could be regarded as evidence of immune attack against beta-cells, and their presence was closely correlated with the presence of either anti-GAD or anti-IA-2 antibodies (P = 0.02). In conclusion, pancreatic biopsy under laparoscope is a safe procedure without serious complications, according to our findings, for detecting in situ autoimmune phenomenon in recent-onset type 1 diabetic patients.


Assuntos
Autoimunidade , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Imunidade Celular , Pâncreas/patologia , Adolescente , Adulto , Autoanticorpos/análise , Biomarcadores , Biópsia/efeitos adversos , Feminino , Humanos , Imuno-Histoquímica , Ilhotas Pancreáticas/imunologia , Masculino , Pessoa de Meia-Idade
19.
Glycobiology ; 11(2): 165-74, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11287403

RESUMO

The alpha1,6 fucosyltransferase (alpha1,6 FucT) catalyzes the transfer of a fucose from GDP-fucose to the innermost GlcNAc residue of N-linked glycans via an alpha1,6 linkage. alpha1,6 FucT was overexpressed in transgenic mice under the control of a combined cytomegalovirus and chicken beta-actin promoter. Histologically numerous small vacuoles, in which lipid droplets had accumulated, were observed in hepatocytes and proximal renal tubular cells. Electron microscopic studies showed that the lipid droplets were membrane-bound and apparently localized within the lysosomes. Cholesterol esters and triglycerides were significantly increased in liver and kidney of the transgenic mice. Liver lysosomal acid lipase (LAL) activity was significantly lower in the transgenic mice compared to the wild mice, whereas LAL protein level, which was detected immunochemically, was increased, indicating that the specific activity of LAL was much lower in the transgenic mice. In all of the transgenic and nontransgenic mice examined, the activity of liver LAL was negatively correlated with the level of alpha1,6 FucT activity. As evidenced by lectin and immunoblot analysis, LAL was found to be more fucosylated in the transgenic mice, suggesting that the aberrant fucosylation of LAL causes an accumulation of inactive LAL in the lysosomes. Such an accumulation of inactive LAL could be a likely cause for a steatosis in the lysosomes of the liver and kidney in the case of the alpha1,6 FucT transgenic mice.


Assuntos
Fucosiltransferases/metabolismo , Rim/enzimologia , Lipase/metabolismo , Hepatopatias/enzimologia , Fígado/enzimologia , Lisossomos/enzimologia , Animais , Humanos , Lipídeos/sangue , Camundongos , Camundongos Transgênicos
20.
Diabetes Res Clin Pract ; 52(3): 171-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11323086

RESUMO

Heterozygous mutations in the genes encoding transcription factors (HNF-1alpha, HNF-1beta and HNF-4alpha) in the hepatocyte nuclear factor (HNF) network are associated with maturity-onset diabetes of the young (MODY). We screened HNF-6 gene for mutations in 34 Japanese subjects with MODY/early-onset diabetes mellitus and 56 subjects with late-onset diabetes mellitus. One single nucleotide polymorphism (SNP) at codon 287 (GGG to GGT) was found in the gene and the frequency was similar among MODY/early-onset diabetes, late-onset diabetes and control subjects. Genetic variations in the HNF-6 gene are not likely to contribute to the susceptibility to diabetes mellitus in Japanese.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteínas de Homeodomínio/genética , Mutação , Transativadores/genética , Adolescente , Adulto , Idade de Início , Povo Asiático , Família , Frequência do Gene , Predisposição Genética para Doença , Variação Genética , Fator 6 Nuclear de Hepatócito , Humanos , Japão , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
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