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1.
Endocr J ; 62(5): 399-409, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25739726

RESUMO

There is little information on direct comparison between metformin and glucagon-like peptide-1 (GLP-1) receptor agonists in the Asian population. This study examined the efficacy and safety of liraglutide monotherapy compared with metformin monotherapy in overweight/obese Japanese patients with type 2 diabetes (T2DM). The study was a 24-week, open-labeled, randomized controlled study. Overweight or obese patients with T2DM aged 20-75 years with suboptimal glycemic control were randomized to liraglutide or metformin monotherapy. The primary endpoint was change in HbA1c at week 24. Secondary endpoints included changes in daily glycemic profile, body weight, incidence of hypoglycemia and other adverse events. The study, which was originally planned to enroll 50 subjects in each group, was ended with insufficient recruitment. A total of 46 subjects completed the study, and analysis was conducted in this cohort. Reduction in HbA1c at week 24 was comparable between the metformin (n = 24) and liraglutide (n = 22) groups (-0.95 ± 0.80% vs. -0.80 ± 0.88%, p = 0.77), while the liraglutide group reached maximal reduction more rapidly than did the metformin group. There was no significant difference in weight gain or incidence of hypoglycemia between the groups. Diarrhea was more frequent in the metformin group, while constipation was more frequent in the liraglutide group. There was no significant difference in treatment satisfaction between the groups. In conclusion, liraglutide and metformin monotherapy showed similar reduction in HbA1c during 24 weeks, with no difference in weight gain or incidence of hypoglycemia in overweight or obese Japanese patients with T2DM.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes , Liraglutida/uso terapêutico , Metformina/uso terapêutico , Obesidade/complicações , Sobrepeso/complicações , Adulto , Idoso , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/induzido quimicamente , Japão , Liraglutida/efeitos adversos , Masculino , Metformina/efeitos adversos , Pessoa de Meia-Idade , Aumento de Peso
2.
Diabetes Metab Res Rev ; 27(8): 951-3, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22069291

RESUMO

BACKGROUND: It has been reported that intervention with insulin in slowly progressive type 1 diabetic (SPIDDM) patients delays the progression to an insulin-dependent state compared to that with sulfonylureas. However, the rate of progression to SPIDDM with the use of insulin-sensitizing agents is unknown. The aim of this study was to determine the effect of insulin-sensitizing agents on SPIDDM patients. METHODS: The enrolled SPIDDM patients were randomly allocated to a pioglitazone or metformin group. When the haemoglobin A1C level was more than 8% on two consecutive occasions, the case was considered to reach the end point. RESULTS: By 4 years post-intervention, all patients had reached the end point in the pioglitazone group, whereas only 20% of patients had reached the end point in the metformin group (p<0.05). CONCLUSIONS: Pioglitazone may accelerate the disease course of SPIDDM.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Tiazolidinedionas/efeitos adversos , Adulto , Idade de Início , Progressão da Doença , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pioglitazona
3.
Rev Diabet Stud ; 7(3): 209-24, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21409313

RESUMO

OBJECTIVE: Complete Freund's Adjuvant (CFA) is known to arrest autoimmune diabetes development in non-obese diabetic (NOD) mice. However, CFA alone cannot induce effective remission in diabetic NOD mice. Previously, we reported that anti-CXC chemokine ligand 10 (CXCL10) antibody can promote beta-cell proliferation in NOD mice. In the present study, we aimed to examine whether anti-CXCL10 plus CFA treatment can effectively reverse autoimmune diabetes development. METHODS: Systemic supply of anti-CXCL10 antibody by CXCL10 DNA vaccination in combination with CFA injection was performed in new-onset diabetic NOD mice. Remission rate of diabetes, histological characteristics of residual insulitis lesions, residual beta-cell mass, and regulatory T cell population in local pancreas were examined. RESULTS: A high frequency of diabetes reversal was observed after combination treatment with anti-CXCL10 plus CFA. In mice showing diabetes reversal, residual beta-cell mass was significantly increased, and some beta-cells were in a proliferative state. Although systemic cytokine profiles were unaffected, the frequency of "hybrid regulatory T cells", i.e. regulatory T cells expressing CXCR3, was significantly increased in local pancreatic lesions. This was possibly associated with the regulation of anti-islet autoimmunity. CONCLUSIONS: Anti-CXCL10 plus appropriate immune adjuvant therapy arrested, and reversed, type 1 diabetes development.


Assuntos
Quimiocina CXCL10/imunologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Adjuvante de Freund/uso terapêutico , Hiperglicemia/tratamento farmacológico , Vacinas de DNA/uso terapêutico , Animais , Anticorpos/uso terapêutico , Quimiocina CXCL10/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Modelos Animais de Doenças , Feminino , Humanos , Hiperglicemia/imunologia , Hiperglicemia/prevenção & controle , Camundongos , Camundongos Endogâmicos NOD , Ratos , Vacinação , Vacinas de DNA/imunologia
4.
Intern Med ; 48(9): 657-63, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19420810

RESUMO

OBJECTIVE: The significance of estimated glomerular filtration rate (e-GFR) in diabetic nephropathy has yet to be clearly determined. We therefore compared albuminuria and e-GFR for usefulness in predicting progressive decline in renal function. METHODS: A total of 1,303 subjects with type 2 diabetes mellitus whose e-GFR was more than 30 mL/min/1.73 m(2) were followed for three years. Associations of clinical staging based on AER and that based on e-GFR with progression of renal insufficiency (e-GFR <30 mL/min/1.73 m(2)) were evaluated. RESULTS: On univariate analysis, both clinical stages based on e-GFR and AER were significant variables (p<0.05). On multiple logistic regression analysis, the odds ratio for macroalbuminuria was 132.3, and that for microalbuminuria was 10.3 while that for e-GFR less than 60 mL/min/1.73 m(2) was 9.0 for further deterioration of renal function. On the other hand, subjects without albuminuria exhibited a rate of disease progression of less than 1% irrespective of e-GFR level. CONCLUSIONS: Both albuminuria and reduced e-GFR are significant and independent risk factors for further deterioration of diabetic nephropathy, though albuminuria had a greater odds ratio than reduced e-GFR for deterioration of renal function over a three-year period. e-GFR exhibited additive risk for deterioration of diabetic nephropathy within three years only when albuminuria was present.


Assuntos
Albuminúria/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Taxa de Filtração Glomerular/fisiologia , Falência Renal Crônica/fisiopatologia , Idoso , Albuminúria/complicações , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/etiologia , Feminino , Humanos , Rim/fisiologia , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
5.
Diabetes Res Clin Pract ; 79(1): 18-23, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17919765

RESUMO

At the onset of type 1 diabetes, most of the insulin-producing pancreatic beta cells are destroyed by effector cells, and therefore, the following two factors, at a minimum, are necessary for "reversing" hyperglycemia in autoimmune diabetes; depletion of effector cells and enhancement of beta cell regeneration. In this study, we tried a novel approach for "reversing" autoimmune diabetes in a murine model. Here we show that remission could be achieved with a combination therapy of a single injection of complete Freund's adjuvant (CFA) and a single intraperitoneal injection of a pancreatic beta cell line, MIN6N-9a, in recent-onset diabetic NOD (non-obese diabetic) mice. Five out of seven mice (71%) receiving MIN6N-9a and CFA became normoglycemic within 120 days after treatment, whereas only two of nine (22%) receiving vehicle instead of MIN6N-9a achieved remission. Histological examination of pancreatic specimens from "reversed" mice showed decreased islet number, but each islet was markedly hyperplastic; being about six times larger than those from controls. Although it has been reported that hematopoietic cells such as splenocytes differentiate into insulin-producing cells and play a key role, our data indicate that they are not an absolute requirement for the "reversal" of autoimmune diabetes.


Assuntos
Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/patologia , Transplante Homólogo/fisiologia , Animais , Feminino , Transplante de Células-Tronco Hematopoéticas , Hiperplasia , Insulina/genética , Interferon gama/genética , Ilhotas Pancreáticas/anatomia & histologia , Camundongos , Camundongos Endogâmicos ICR , Camundongos Endogâmicos NOD , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Arthritis Rheum ; 56(7): 2211-5, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17599739

RESUMO

OBJECTIVE: Results of recent studies suggest that human chorionic gonadotropin (HCG), a placental glycoprotein hormone required for the maintenance of pregnancy, may have immunomodulatory properties. Primary Sjögren's syndrome (SS), a chronic autoimmune disorder of unknown etiology, affects multiple exocrine glands including the salivary and lacrimal glands. The purpose of the present study was to determine whether HCG could prevent the development of salivary gland exocrinopathy in NOD mice, an experimental model of Sjögren's-like syndrome. METHODS: Female NOD mice were treated with HCG from 6 weeks of age to 12 weeks of age. At 14 weeks, tissue samples were evaluated for inflammatory lesions and cytokine messenger RNA by real-time polymerase chain reaction. At 18 weeks, the salivary flow rate was measured. RESULTS: Treatment with HCG resulted in a significant decrease in lymphocyte infiltration and parenchymal cell damage in the submandibular salivary glands. Messenger RNA levels of interferon-gamma, tumor necrosis factor alpha, interleukin-1beta, and interleukin-10, as well as inducible nitric oxide synthase and matrix metalloproteinase 9, were significantly decreased. Function studies revealed a marked increase in the salivary flow rate in HCG-treated mice compared with that in phosphate buffered saline-treated mice. CONCLUSION: In NOD mice, HCG acts as an immune modulator and prevents the development of salivary gland exocrinopathy. These findings suggest that HCG, a naturally occurring reproductive hormone, may be useful in the treatment of Sjögren's syndrome and other human autoimmune diseases.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Síndrome de Sjogren/prevenção & controle , Animais , Citocinas/genética , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/prevenção & controle , Interferon gama/genética , Interleucina-4/genética , Camundongos , Camundongos Endogâmicos NOD , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Saliva/metabolismo , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/patologia
7.
Diabetes ; 56(6): 1671-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17369525

RESUMO

Long-term treatment with glucagon-like peptide (GLP)-1 or its analog can improve insulin sensitivity. However, continuous administration is required due to its short half-life. We hypothesized that continuous production of therapeutic levels of GLP-1 in vivo by a gene therapy strategy may remit hyperglycemia and maintain prolonged normoglycemia. We produced a recombinant adenovirus expressing GLP-1 (rAd-GLP-1) under the cytomegalovirus promoter, intravenously injected it into diabetic ob/ob mice, and investigated the effect of this treatment on remission of diabetes, as well as the mechanisms involved. rAd-GLP-1-treated diabetic ob/ob mice became normoglycemic 4 days after treatment, remained normoglycemic over 60 days, and had reduced body weight gain. Glucose tolerance tests found that exogenous glucose was cleared normally. rAd-GLP-1-treated diabetic ob/ob mice showed improved beta-cell function, evidenced by glucose-responsive insulin release, and increased insulin sensitivity, evidenced by improved insulin tolerance and increased insulin-stimulated glucose uptake in adipocytes. rAd-GLP-1 treatment increased basal levels of insulin receptor substrate (IRS)-1 in the liver and activation of IRS-1 and protein kinase C by insulin in liver and muscle; increased Akt activation was only observed in muscle. rAd-GLP-1 treatment reduced hepatic glucose production and hepatic expression of phosphoenolpyruvate carboxykinase, glucose-6-phosphatase, and fatty acid synthase in ob/ob mice. Taken together, these results show that a single administration of rAd-GLP-1 results in the long-term remission of diabetes in ob/ob mice by improving insulin sensitivity through restoration of insulin signaling and reducing hepatic gluconeogenesis.


Assuntos
Diabetes Mellitus Experimental/terapia , Terapia Genética , Peptídeo 1 Semelhante ao Glucagon/genética , Insulina/fisiologia , Fígado/metabolismo , Animais , Gluconeogênese , Teste de Tolerância a Glucose , Camundongos , Camundongos Obesos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Mol Ther ; 15(1): 86-93, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28182934

RESUMO

Type 1 diabetes results from insulin deficiency caused by destruction of pancreatic ß cells. Glucagon-like peptide (GLP)-1 stimulates ß cell growth and differentiation. To determine whether continuous expression of GLP-1 in vivo can regenerate ß cells and remit type 1 diabetes in mice for a prolonged time, we constructed an adenoviral vector containing the cytomegalovirus promoter/enhancer and albumin leader sequence followed by GLP-1 cDNA (rAd-GLP-1). A single administration of rAd-GLP-1 via the tail vein into streptozotocin (STZ)-induced diabetic non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice resulted in remission of diabetes within 10 days; normoglycemia remained until the experiment was terminated. The number of insulin-positive cells in the pancreas and insulin secretion significantly increased in rAd-GLP-1-treated mice compared with STZ-induced diabetic mice treated with rAd-ß-galactosidase. Glucose tolerance tests in mice that achieved normoglycemia after treatment with rAd-GLP-1 showed that the kinetics of glucose clearance was similar to normal NOD/SCID mice. Treatment of autoimmune diabetic mice with rAd-GLP-1 restored normoglycemia, which was maintained for 1 year when mice were also treated with an immunoregulator to halt the autoimmune response to ß cells. We suggest that regeneration of insulin-producing cells by GLP-1 gene therapy may be a potential method for prolonged control of type 1 diabetes in humans.

9.
Mol Ther ; 15(1): 86-93, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17164779

RESUMO

Type 1 diabetes results from insulin deficiency caused by destruction of pancreatic beta cells. Glucagon-like peptide (GLP)-1 stimulates beta cell growth and differentiation. To determine whether continuous expression of GLP-1 in vivo can regenerate beta cells and remit type 1 diabetes in mice for a prolonged time, we constructed an adenoviral vector containing the cytomegalovirus promoter/enhancer and albumin leader sequence followed by GLP-1 cDNA (rAd-GLP-1). A single administration of rAd-GLP-1 via the tail vein into streptozotocin (STZ)-induced diabetic non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice resulted in remission of diabetes within 10 days; normoglycemia remained until the experiment was terminated. The number of insulin-positive cells in the pancreas and insulin secretion significantly increased in rAd-GLP-1-treated mice compared with STZ-induced diabetic mice treated with rAd-beta-galactosidase. Glucose tolerance tests in mice that achieved normoglycemia after treatment with rAd-GLP-1 showed that the kinetics of glucose clearance was similar to normal NOD/SCID mice. Treatment of autoimmune diabetic mice with rAd-GLP-1 restored normoglycemia, which was maintained for 1 year when mice were also treated with an immunoregulator to halt the autoimmune response to beta cells. We suggest that regeneration of insulin-producing cells by GLP-1 gene therapy may be a potential method for prolonged control of type 1 diabetes in humans.


Assuntos
Adenoviridae/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/prevenção & controle , Expressão Gênica/genética , Vetores Genéticos/genética , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Células Secretoras de Insulina/metabolismo , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Linhagem Celular , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/imunologia , Terapia Genética , Peptídeo 1 Semelhante ao Glucagon/genética , Humanos , Imuno-Histoquímica , Insulina/sangue , Insulina/genética , Camundongos , RNA Mensageiro/genética , Estreptozocina/farmacologia
10.
Ann N Y Acad Sci ; 1079: 251-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17130562

RESUMO

One of the CTLA-4 SNPs, +6230G>A (CT60), has recently been reported to be related to susceptibility to type 1 diabetes and autoimmune thyroid disease. We have previously reported an association between acute-onset type 1 diabetes in Japanese and the Vitamin D receptor (VDR) gene Bsm I large B polymorphism, which is related to the Th1-type response. Moreover, we found a significant correlation between autoimmune-related type 1 diabetes with HLA DR9 and detection of GAD-reactive Th1 (T helper 1)-type cells. In the present article, we tried to clarify whether the frequency of one of the CTLA-4 SNPs, +6230G>A (CT60), is affected by the VDR gene Bsm I polymorphism or by HLA DR9 in Japanese type 1 diabetics. The frequency of the CT60 GG genotype did not appear to be affected by either the VDR gene Bsm I large B polymorphism or HLA DR9.


Assuntos
Antígenos CD/genética , Antígenos de Diferenciação/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Frequência do Gene , Polimorfismo Genético , Adulto , Idade de Início , Alelos , Antígeno CTLA-4 , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Antígenos HLA-DR/genética , Humanos , Japão/epidemiologia , Masculino , Receptores de Calcitriol/genética
11.
Ann N Y Acad Sci ; 1079: 365-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17130580

RESUMO

Thiazolidinediones improve glycemic control by reducing insulin resistance. Some studies have demonstrated that troglitazone had a preventative effect on diabetes in NOD (non-obese diabetic) mice. One of the mechanisms proposed for the prevention of diabetes by thiazolidinediones is an effect on T-helper 1/T-helper 2 (Th1/Th2) balance. In this article, we attempted to clarify whether pioglitazone is also effective in preventing diabetes as compared to metformin, which has no immunological effect. Female NOD mice were administered pioglitazone or metformin orally, and the insulitis score, cytokines secreted from splenocytes, cytokine expression levels in the pancreas, and the incidence of diabetes after acceleration by cyclophosphamide were analyzed. We could not find any advantage of pioglitazone in preventing Th1 skewing and the development of diabetes over metformin. Therefore, further research should take place before the application of thiazolidinediones to human slowly progressive insulin-dependent diabetes mellitus (SPIDDM) patients.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/prevenção & controle , Incidência , Tiazolidinedionas/farmacologia , Animais , Ciclofosfamida/administração & dosagem , Ciclofosfamida/toxicidade , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Progressão da Doença , Feminino , Imunossupressores/administração & dosagem , Imunossupressores/toxicidade , Ilhotas Pancreáticas/metabolismo , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos NOD , Pioglitazona , Distribuição Aleatória , Baço/citologia , Baço/imunologia
12.
J Autoimmun ; 26(1): 66-71, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16309891

RESUMO

Although we have previously reported an elevated serum level of CXCL10/IP-10 (CXCL10), a Th1 chemokine, in type 1 diabetic patients, little is known about the origin of serum CXCL10 and its significance in type 1 diabetes. Therefore, we examined serum CXCL10 level in NOD mice in association with the expression level of CXCL10 in the pancreas, pancreatic lymph nodes (LN) and spleen. Serum CXCL10 level increased over time towards the onset of diabetes, and was significantly higher in the "diabetic" period (20 and 24 weeks of age and at onset of diabetes) than in the "pre-diabetic" period (4, 8 and 16 weeks of age). Moreover, serum CXCL10 level was associated with CXCL10 and CXCR3 mRNA level in pancreatic LN. Furthermore, it seemed that serum CXCL10 level increased just before (or at) the onset of overt diabetes. These results suggest that serum CXCL10 level may reflect accumulation of Th1 lymphocytes in pancreatic LN, and measurement of serum CXCL10 level may be useful to assess the pathophysiology of the disease course in type 1 diabetes.


Assuntos
Quimiocinas CXC/sangue , Diabetes Mellitus Tipo 1/imunologia , Pâncreas/imunologia , Células Th1/imunologia , Animais , Quimiocina CXCL10 , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Feminino , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos NOD , Pâncreas/citologia , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Receptores CXCR3 , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo , Baço/citologia , Baço/imunologia
13.
J Immunol ; 175(12): 8401-8, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16339582

RESUMO

CXCL10, a chemokine for Th1 cells, is involved in the pathogenesis of various Th1-dominant autoimmune diseases. Type 1 diabetes is considered to be a Th1-dominant autoimmune disease, and a suppressive effect of CXCL10 neutralization on diabetes development has been reported in a cyclophosphamide-induced accelerated diabetes model through induction of beta cell proliferation. However, intervention in a diabetes model might bring about opposite effects, depending on the timing, amount, or method of treatment. In the present study, we examined the effect of CXCL10 neutralization in a "spontaneous diabetes" model of NOD mice, using CXCL10 DNA vaccination (pCAGGS-CXCL10). pCAGGS-CXCL10 treatment in young NOD mice induced the production of anti-CXCL10 Ab in vivo and suppressed the incidence of spontaneous diabetes, although this treatment did not inhibit insulitis or alter the immunological response. pCAGGS-CXCL10 treatment enhanced the proliferation of pancreatic beta cells, resulting in an increase of beta cell mass in this spontaneous diabetes model as well. Therefore, CXCL10 neutralization is suggested to be useful for maintaining beta cell mass at any stage of autoimmune diabetes.


Assuntos
Quimiocinas CXC/uso terapêutico , Diabetes Mellitus Tipo 1/prevenção & controle , Células Secretoras de Insulina/citologia , Vacinas de DNA , Animais , Formação de Anticorpos , Proliferação de Células , Quimiocina CXCL10 , Quimiocinas CXC/genética , Quimiocinas CXC/imunologia , Citocinas/biossíntese , Feminino , Camundongos , Camundongos Endogâmicos NOD , Plasmídeos
14.
Autoimmunity ; 37(6-7): 481-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15621575

RESUMO

Spontaneous diabetes in non-obese diabetic (NOD) mice results from beta-cell destruction by autoreactive T lymphocytes. Here, we report the significance of insulin-like growth factor-1 (IGF-1) peptide as a tool for the prevention of type 1 diabetes. Female NOD mice were immunized with a subcutaneous injection of IGF-1, glutamic acid decarboxylase (GAD), insulin or IGF-1-derived peptides (residues 8-23, 24-41 or 50-70) in incomplete Freund's adjuvant (IFA) or with IFA only as the control group at 4 weeks of age, and observed up to 36-37 weeks of age. Diabetes onset was significantly suppressed and delayed in the IGF-1 group as compared to the GAD, insulin and control groups (p<0.05), and it was significantly suppressed and delayed in the (50-70)IGF-1 group as compared to the (8-23)IGF-1 and control groups (p<0.02). Although the degree of insulitis in all treated mice was not significantly different, a significant number of IL-4-producing cells in response to IGF-1 peptides were detected in (50-70)IGF-1-treated mice in intracellular cytokine assay. In conclusion, IGF-1 peptide 50-70 immunizations of NOD mice suppressed and delayed diabetes onset, probably through amplification of the Th2-type response. It was suggested that IGF-1 peptide 50-70 immunization can be used as a tool for prevention of type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/prevenção & controle , Fragmentos de Peptídeos/uso terapêutico , Fatores Etários , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Feminino , Fator de Crescimento Insulin-Like I/genética , Camundongos , Camundongos Endogâmicos NOD , Fragmentos de Peptídeos/genética , Células Th2/efeitos dos fármacos
15.
J Immunol ; 173(11): 7017-24, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15557199

RESUMO

We have shown that neutralization of IFN-inducible protein 10/CXCL10, a chemokine for Th1 cells, breaks Th1 retention in the draining lymph nodes, resulting in exacerbation in Th1-dominant autoimmune disease models induced by immunization with external Ags. However, there have been no studies on the role of CXCL10 neutralization in Th1-dominant disease models induced by constitutive intrinsic self Ags. So, we have examined the effect of CXCL10 neutralization using a type 1 diabetes model initiated by developmentally regulated presentation of beta cell Ags. CXCL10 neutralization suppressed the occurrence of diabetes after administration with cyclophosphamide in NOD mice, although CXCL10 neutralization did not significantly inhibit insulitis and gave no influence on the trafficking of effector T cells into the islets. Because both CXCL10 and CXCR3 were, unexpectedly, coexpressed on insulin-producing cells, CXCL10 was considered to affect mature and premature beta cells in an autocrine and/or paracrine fashion. In fact, CXCL10 neutralization enhanced proliferative response of beta cells and resultantly increased beta cell mass without inhibiting insulitis. Thus, CXCL10 neutralization can be a new therapeutic target for beta cell survival, not only during the early stage of type 1 diabetes, but also after islet transplantation.


Assuntos
Proliferação de Células , Quimiocinas CXC/antagonistas & inibidores , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Terapia de Imunossupressão , Ilhotas Pancreáticas/patologia , Animais , Anticorpos Bloqueadores/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Quimiocina CXCL10 , Quimiocinas CXC/biossíntese , Quimiocinas CXC/imunologia , Quimiotaxia de Leucócito/imunologia , Ciclofosfamida/administração & dosagem , Diabetes Mellitus Tipo 1/patologia , Progressão da Doença , Feminino , Terapia de Imunossupressão/métodos , Injeções Intraperitoneais , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Receptores CXCR3 , Receptores de Quimiocinas/biossíntese , Linfócitos T/imunologia , Linfócitos T/patologia
17.
Ann N Y Acad Sci ; 1037: 33-40, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15699491

RESUMO

Type 1 diabetes mellitus (T1DM) is considered to be a T cell-mediated disease, and many reports suggest that some HLA types, especially HLA DR4 and DR9, convey susceptibility to T1DM in Japanese. We investigated the association between T cell reactivity against GAD and HLA types in "islet-associated autoantibody-positive" T1DM in Japanese. Blood samples were obtained from 36 "autoantibody-positive" type 1 diabetic patients with HLA DR4 or DR9 and 23 type 2 diabetic patients with HLA DR4 or DR9 as controls. They were divided into three groups, DR4/9, DR4/X, and DR9/X groups. In each HLA type group, GAD-reactive IFN-gamma-producing CD4(+) cells were assessed by means of intracellular cytokine staining for flow cytometry. Type 1 diabetic patients with HLA DR9/X had significantly higher numbers of GAD-reactive IFN-gamma-producing CD4(+) cells as compared to type 1 diabetic patients with DR4/X or DR4/9 (P < 0.05) and all type 2 diabetic patients. There was no significant difference in the number of GAD-reactive IFN-gamma-producing CD4(+) cells between type 1 diabetic and type 2 diabetic patients belonging to the DR4/X and DR4/9 groups. There was an association between T cell reactivity against GAD and HLA DR9 in Japanese type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Antígenos HLA-DR/genética , Linfócitos T/enzimologia , Adulto , Idoso , Povo Asiático , Autoanticorpos/sangue , Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2 , Feminino , Citometria de Fluxo , Antígeno HLA-DR4/genética , Teste de Histocompatibilidade , Humanos , Interferon gama/metabolismo , Masculino , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteínas Tirosina Fosfatases/imunologia , Ensaio Radioligante , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores
18.
Ann N Y Acad Sci ; 1005: 324-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14679084

RESUMO

Type 1 diabetes is caused by the immune-mediated destruction of insulin-secreting pancreatic beta cells and is thought to be an autoimmune disease resulting from a complex interaction of genetic and environmental factors. In animal models of type 1 diabetes, macrophages and their products, superoxides, have central roles in the beta cell destruction, but in humans their roles remain unclear. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase produces superoxide in macrophages, and its essential component, p22 phox, is a critical enzyme for superoxide production. The C242T polymorphism in the p22 phox coding gene has been reported to be associated with reduced oxidase activity. We therefore investigated whether the p22 phox gene polymorphism affected the susceptibility to and clinical course of type 1 diabetes. We examined 287 Japanese type 1 diabetic patients and 425 unrelated nondiabetic subjects. In addition, we allocated the diabetic patients to the following three groups: (1) acute-onset type 1 diabetes with at least one autoantibody (GADA, IA-2, IAA); (2) acute-onset type 1 diabetes without autoantibodies; and (3) slow-onset type 1 diabetes with autoantibody. We could not find a significant difference in p22 phox genotype and T allele frequency between overall type 1 diabetic patients and control subjects. Regardless of the onset pattern and autoantibody positivity of type 1 diabetes, no difference in p22 phox genotype and T allele frequency was found among the groups. In conclusion, the p22 phox C242T gene polymorphism did not affect the susceptibility to and clinical course of Japanese type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/genética , Proteínas de Membrana Transportadoras , NADPH Desidrogenase/genética , Fosfoproteínas/genética , Polimorfismo Genético , Sequência de Bases , Primers do DNA , Humanos , NADPH Oxidases , Estresse Oxidativo
19.
Ann N Y Acad Sci ; 1005: 328-31, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14679085

RESUMO

Type 1 diabetes is characterized by cell-mediated autoimmune destruction of pancreatic beta cells. Although the disease shows a strong association with HLA class II alleles, other genes may influence the initiation or the rate of progression of the autoimmune process. Recently, it was reported that a polymorphism of the stromal cell-derived factor-1 (SDF-1) (a kind of chemokine) gene was associated with early onset of type 1 diabetes in Caucasians. Therefore, we examined SDF-1 gene polymorphism in Japanese type 1 diabetes in this study. We examined the SDF-1 gene polymorphism (801G-->A) in 298 unrelated Japanese type 1 diabetic patients and 270 healthy subjects by the TaqMan PCR method. Allelic and genotypic frequencies of the SDF-1 A variants were similar in overall type 1 diabetic patients and healthy subjects. We then stratified the patients by their onset pattern (acute vs. slow onset) and islet-associated autoantibody positivity. However, no significant difference was found among each group of type 1 diabetes. Furthermore, unlike the previous report in "Caucasian" type 1 diabetics, the SDF-1 A variant was not associated with early onset of the disease in Japanese type 1 diabetics. The SDF-1 gene polymorphism was not associated with onset age (or onset pattern) of type 1 diabetes in Japanese. Further study is necessary to conclude whether SDF-1 gene polymorphism affects the onset age in type 1 diabetes in general.


Assuntos
Quimiocinas CXC/genética , Polimorfismo Genético , Adulto , Estudos de Casos e Controles , Quimiocina CXCL12 , Humanos , Japão
20.
Ann N Y Acad Sci ; 1005: 359-61, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14679092

RESUMO

Recently, a novel subtype of type 1 diabetes, so-called fulminant type 1 diabetes, has been proposed. One of the characteristics of this subtype is the absence of detectable "islet-associated" autoantibody, so it was originally proposed as being "nonautoimmune-mediated"; however, it has not yet been concluded whether autoimmunity is involved. We have previously shown that serum interferon-inducible protein-10 and glutamic acid decarboxylase-reactive CD4(+) interferon-gamma-producing cells in the peripheral blood are good markers for T cell-mediated autoimmunity in type 1 diabetes. Here, we report two cases of fulminant type 1 diabetes in which these markers were detected and in which the involvement of islet-associated autoimmunity is suggested.


Assuntos
Autoimunidade , Diabetes Mellitus Tipo 1/imunologia , Adulto , Autoanticorpos/sangue , Quimiocina CXCL10/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Glutamato Descarboxilase/imunologia , Humanos , Isoenzimas/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
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