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1.
Ann Hematol ; 101(8): 1803-1813, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35604470

RESUMO

Organizing pneumonia (OP) is a complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and a manifestation of peripheral airway/alveolar inflammation. Recently, alveolar nitric oxide concentration (Calv) has been revealed as a noninvasive marker of peripheral airway inflammation; however, whether Calv levels are associated with OP and peripheral airway in patients after allo-HSCT remains unclear. Herein, we evaluated whether Calv levels could reflect the presence of OP and structural airway changes in patients after allo-HSCT. We measured the eNO levels of 38 patients (6 with OP and 32 without OP) who underwent allo-HSCT. Three-dimensional computed tomography (CT) analysis of the airway was performed in 19 patients. We found that in patients with OP, Calv levels were significantly higher than in those without OP (10.6 vs. 5.5 ppb, p < 0.01). Receiver-operating characteristic analyses revealed a Calv cut-off value for OP detection of 10.2 ppb. No significant differences in the patient characteristics, except for the presence of OP (p < 0.01), were noted between the two groups stratified by the Calv cut-off value. Three-dimensional CT images of the airway revealed gradually increasing positive correlations between Calv levels and airway wall area of the third-, fourth-, and fifth-generation bronchi (r = 0.20, 0.31, 0.38; p = 0.42, 0.19, 0.038, respectively), indicating that Calv levels are strongly correlated with the wall thickness of the distal bronchi. Our results suggest that the Calv level may be a useful noninvasive detectable marker for OP after an allo-HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Pneumonia , Biomarcadores/análise , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Inflamação/complicações , Óxido Nítrico/análise , Pneumonia/etiologia , Estudos Retrospectivos , Tórax/química
2.
Int J Mol Sci ; 23(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36362372

RESUMO

Endoplasmic reticulum (ER) stress is a key pathogenic factor in type 1 and 2 diabetes. Glycogen synthase kinase 3 (Gsk-3) contributes to ß-cell loss in mice. However, the mechanism by which Gsk-3 leads ß-cell death remains unclear. ER stress was pharmacologically induced in mouse primary islets and insulinoma cells. We used insulinoma cells derived from Akita mice as a model of genetic ER stress. Gsk-3 activity was blocked by treating with Gsk-3 inhibitors or by introducing catalytically inactive Gsk-3ß. Gsk-3 inhibition prevented proteasomal degradation of activating transcriptional factor 4 (ATF4) and alleviated apoptosis. We found that ATF4-S214 was phosphorylated by Gsk-3, and that this was required for a binding of ATF4 with ßTrCP, which mediates polyubiquitination. The anti-apoptotic effect of Gsk-3 inhibition was attenuated by introducing DN-ATF4 or by knockdown of ATF4. Mechanistically, Gsk-3 inhibition modulated transcription targets of ATF4 and in turn facilitated dephosphorylation of eIF2α, altering the protein translational dynamism under ER stress. These observations were reproduced in the Akita mouse-derived cells. Thus, these results reveal the role of Gsk-3 in the regulation of the integrated stress response, and provide a rationale for inhibiting this enzyme to prevent ß-cell death under ER stress conditions.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Insulinoma , Neoplasias Pancreáticas , Camundongos , Animais , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Transdução de Sinais , Estresse do Retículo Endoplasmático , Apoptose
3.
Biochem Biophys Res Commun ; 534: 415-421, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33256979

RESUMO

The liver is the major organ maintaining metabolic homeostasis in animals during shifts between fed and fasted states. Circadian oscillations in peripheral tissues including the liver are connected with feeding-fasting cycles. We generated transgenic mice with hepatocyte specific E4BP4, D-box negative regulator, overexpression. Liver-specific E4BP4 overexpression was also achieved by adenoviral gene transfer. Interestingly, hepatic E4BP4 overexpression induced marked insulin resistance, that was rescued by DBP, a competing D-box positive regulator, overexpression. At basal conditions hepatocyte E4BP4 transgenic mice exhibited increased gluconeogenesis with reduced AKT phosphorylation in liver. In muscle, AKT phosphorylation was impaired after insulin stimulation. Such muscle insulin resistance was associated with elevated free fatty acid flux from the liver and reduced fatty acid utilization as an energy source during the inactive phase. E4BP4, one of the clock-controlled output genes, are key metabolic regulators in liver adjusting liver and muscle metabolism and insulin sensitivity in the feeding-fasting cycles. Its tuning is critical for preventing metabolic disorders.


Assuntos
Relógios Circadianos , Metabolismo Energético , Fígado/metabolismo , Músculo Esquelético/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Gorduras/metabolismo , Gluconeogênese , Resistência à Insulina , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Regulação para Cima
4.
Pituitary ; 24(4): 582-588, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33666833

RESUMO

Wolfram syndrome (WS) is mainly caused by mutations in the WFS1 gene and characterized by diabetes mellitus, optic atrophy, hearing loss, and central diabetes insipidus (CDI). WFS1 is an endoplasmic reticulum (ER)-resident transmembrane protein, and Wfs1 knockout (Wfs1-/-) mice, which have been used as a mouse model for WS, reportedly manifested impairment of glucose tolerance due to pancreatic ß-cell loss. In the present study, we examined water balance, arginine vasopressin (AVP) secretion, and ER stress in AVP neurons of the hypothalamus in Wfs1-/- mice. There were no differences in urine volumes between Wfs1-/- and wild-type mice with free access to water. Conversely, when mice were subjected to intermittent water deprivation (WD) for 20 weeks, during which water was unavailable for 2 days a week, urine volumes were larger in Wfs1-/- mice, accompanied by lower urine AVP concentrations and urine osmolality, compared to wild-type mice. The mRNA expression of immunoglobulin heavy chain binding protein, a marker of ER stress, was significantly increased in the supraoptic nucleus and paraventricular nuclei in Wfs1-/- mice compared to wild-type mice after WD. Our results thus showed that Wfs1 knockout leads to a decrease in AVP secretion during dehydration, which could explain in part the mechanisms by which Wfs1 mutations cause CDI in humans.


Assuntos
Síndrome de Wolfram , Animais , Desidratação , Diabetes Insípido Neurogênico , Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Masculino , Proteínas de Membrana , Camundongos , Água , Síndrome de Wolfram/genética
5.
Diabetes Obes Metab ; 21(12): 2674-2683, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407845

RESUMO

AIMS: To investigate the efficacy and safety of insulin degludec/liraglutide (IDegLira) compared with its individual components in Japanese people with type 2 diabetes (T2D) uncontrolled on an oral antidiabetic drug (OAD). MATERIALS AND METHODS: This 52-week, open-label, multicentre, treat-to-target trial randomized participants (n = 819) 1:1:1 to IDegLira, liraglutide 1.8 mg or degludec, as add-on to their pre-trial OAD. The maximum IDegLira dose was 50 dose steps (50 U degludec/1.8 mg liraglutide), there was no maximum dose for degludec, and both were titrated based on individual blood glucose measurements. RESULTS: After 52 weeks, glycated haemoglobin (HbA1c) decreased by 26 mmol/mol with IDegLira vs 20 mmol/mol with degludec and liraglutide: estimated treatment differences were -6.91 mmol/mol (95% confidence interval [CI] -8.18; -5.64) and -5.30 mmol/mol (95% CI -6.58; -4.03), confirming non-inferiority of IDegLira to degludec and superiority of IDegLira to liraglutide (P < .0001 for both [primary endpoint]). Mean body weight changes were 2.9 kg, 4.1 kg and -1.0 kg with IDegLira, degludec and liraglutide, respectively, showing superiority of IDegLira versus degludec (P = .0001), but a significant difference in favour of liraglutide (P < .0001). Rates of severe or blood glucose-confirmed hypoglycaemia for IDegLira were lower versus degludec (rate ratio 0.48 [95% CI 0.35; 0.68]; P < .0001), but higher versus liraglutide (rate ratio 37.58 [95% CI 19.80; 71.31]; P < .0001). Mean daily total insulin dose was lower with IDegLira (27.7 U) versus degludec (34.8 U; P < .0001). Overall adverse event (AE) rates were similar. In total, 34.9%, 22.9% and 41.8% of IDegLira-, degludec- and liraglutide-treated participants experienced gastrointestinal AEs. CONCLUSION: IDegLira was superior to degludec and liraglutide in terms of HbA1c reduction and superior to degludec in terms of body weight change and rates of hypoglycaemia in Japanese people with T2D.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Liraglutida/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Combinação de Medicamentos , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Insulina de Ação Prolongada/administração & dosagem , Insulina de Ação Prolongada/efeitos adversos , Japão , Liraglutida/administração & dosagem , Liraglutida/efeitos adversos , Masculino , Pessoa de Meia-Idade
6.
Diabetes Obes Metab ; 21(7): 1737-1744, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30830727

RESUMO

The aim of this study was to evaluate the efficacy and safety of pemafibrate in people with type 2 diabetes and hypertriglyceridaemia over a 52-week period. Participants were randomly assigned to receive treatment with placebo or pemafibrate at a dose of 0.2 or 0.4 mg/d for 24 weeks (treatment period 1). The main results from treatment period 1 have been reported previously. The assigned treatment was continued up to week 52, except that the placebo was changed to pemafibrate 0.2 mg/d after week 24 (treatment period 2). The percentage changes in fasting serum triglyceride (TG) levels at week 52 (last observation carried forward) were -48.2%, -42.3%, and -46.4% in the placebo/pemafibrate 0.2 mg/d (n = 57), pemafibrate 0.2 mg/d (n = 54), and pemafibrate 0.4 mg/d (n = 55) groups, respectively. Levels of TG, non-HDL cholesterol and total cholesterol stably decreased, whereas levels of HDL cholesterol increased with pemafibrate treatments over 52 weeks. Pemafibrate was well tolerated throughout the study period. The present study is the first to show that pemafibrate treatment substantially ameliorated lipid abnormalities and was well tolerated for 52 weeks in people with type 2 diabetes and hypertriglyceridaemia.


Assuntos
Benzoxazóis , Butiratos , Diabetes Mellitus Tipo 2/complicações , Hipertrigliceridemia , Hipolipemiantes , Benzoxazóis/efeitos adversos , Benzoxazóis/uso terapêutico , Butiratos/efeitos adversos , Butiratos/uso terapêutico , Humanos , Hipertrigliceridemia/complicações , Hipertrigliceridemia/tratamento farmacológico , Hipolipemiantes/efeitos adversos , Hipolipemiantes/uso terapêutico , Triglicerídeos/sangue
7.
Diabetologia ; 61(10): 2189-2201, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30054673

RESUMO

AIMS/HYPOTHESIS: Loss of functional beta cells results in a gradual progression of insulin insufficiency in Wolfram syndrome caused by recessive WFS1 mutations. However, beta cell dysfunction in Wolfram syndrome has yet to be fully characterised, and there are also no specific treatment recommendations. In this study, we aimed to characterise beta cell secretory defects and to examine the potential effects of a glucagon-like peptide-1 (GLP-1) receptor agonist on diabetes in Wolfram syndrome. METHODS: Insulin secretory function was assessed by the pancreatic perfusion method in mice used as a model of Wolfram syndrome. In addition, granule dynamics in living beta cells were examined using total internal reflection fluorescence microscopy. Acute and chronic effects of exendin-4 (Ex-4) on glucose tolerance and insulin secretion were examined in young Wfs1-/- mice without hyperglycaemia. Molecular events associated with Ex-4 treatment were investigated using pancreatic sections and isolated islets. In addition, we retrospectively observed a woman with Wolfram syndrome who had been treated with liraglutide for 24 weeks. RESULTS: Treatment with liraglutide ameliorated our patient's glycaemic control and resulted in a 20% reduction of daily insulin dose along with an off-drug elevation of fasting C-peptide immunoreactivity. Glucose-stimulated first-phase insulin secretion and potassium-stimulated insulin secretion decreased by 53% and 59%, respectively, in perfused pancreases of 10-week-old Wfs1-/- mice compared with wild-type (WT) mice. The number of insulin granule fusion events in the first phase decreased by 41% in Wfs1-/- beta cells compared with WT beta cells. Perfusion with Ex-4 increased insulin release in the first and second phases by 3.9-fold and 5.6-fold, respectively, in Wfs1-/- mice compared with perfusion with saline as a control. The physiological relevance of the effects of Ex-4 was shown by the fact that a single administration potentiated glucose-stimulated insulin secretion and improved glucose tolerance in Wfs1-/- mice. Four weeks of administration of Ex-4 resulted in an off-drug amelioration of glucose excursions after glucose loading in Wfs1-/- mice, with insulin secretory dynamics that were indistinguishable from those in WT mice, despite the fact that there was no alteration in beta cell mass. In association with the functional improvements, Ex-4 treatment reversed the increases in phosphorylated eukaryotic initiation factor (EIF2α) and thioredoxin interacting protein (TXNIP), and the decrease in phosphorylated AMP-activated kinase (AMPK), in the beta cells of the Wfs1-/- mice. Furthermore, Ex-4 treatment modulated the transcription of oxidative and endoplasmic reticulum stress-related markers in isolated islets, implying that it was able to mitigate the cellular stresses resulting from Wfs1 deficiency. CONCLUSIONS/INTERPRETATION: Our study provides deeper insights into the pathophysiology of beta cell dysfunction caused by WFS1 deficiency and implies that activation of the GLP-1 receptor signal may alleviate insulin insufficiency and aid glycaemic control in Wolfram syndrome.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células Secretoras de Insulina/citologia , Síndrome de Wolfram/metabolismo , Adulto , Animais , Retículo Endoplasmático/metabolismo , Exenatida/farmacologia , Feminino , Glucose/química , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/patologia , Liraglutida/farmacologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Perfusão , Estudos Retrospectivos , Transdução de Sinais/efeitos dos fármacos
8.
Rinsho Ketsueki ; 59(12): 2574-2577, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30626791

RESUMO

A 30-year-old primigravid woman without a history of thrombocytopenia was referred to our hospital because of severe thrombocytopenia (<1,000 thrombocytes/µl) at 16 weeks of gestation and diagnosed with idiopathic thrombocytopenic purpura (ITP). There was no improvement in the platelet count after treatment with 0.5-1.0 mg/kg/day prednisolone, and the 400 mg/day intravenous immunoglobulin (IVIg) administered for 5 days gradually became ineffective; therefore, a laparoscopic splenectomy was performed at 25 weeks of gestation. The increase in the platelet count after the splenectomy was temporary, but the effects of IVIg therapy improved, and the patient received IVIg therapy seven times in total during her pregnancy. Her platelet count ranged between 10,000 and 70,000/µl after the splenectomy, compared with <5,000/µl before the surgery. The patient underwent an elective cesarean section at 34 weeks of gestation without any significant bleeding. The baby was diagnosed with thrombocytopenia at birth (34,000 thrombocytes/µl) and was administered only one dose of IVIg, which increased the baby's platelet count to a normal level after 14 days. The patient's platelet count also increased after delivery. Splenectomy and repeated IVIg therapy can be considered for refractory severe ITP during pregnancy.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Complicações Hematológicas na Gravidez/terapia , Púrpura Trombocitopênica Idiopática/terapia , Esplenectomia , Adulto , Cesárea , Feminino , Humanos , Recém-Nascido , Contagem de Plaquetas , Prednisolona , Gravidez
9.
Diabetes Obes Metab ; 18(12): 1279-1282, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27488246

RESUMO

The efficacy and safety of once-weekly dulaglutide 0.75 mg (dulaglutide) in Japanese patients with type 2 diabetes (T2D) were evaluated according to subgroups defined by concomitant oral hypoglycaemic agents. This exploratory analysis included data from a randomized, open-label, phase III study that compared dulaglutide with insulin glargine (glargine) (n = 361). The three subgroups were dulaglutide or glargine in combination with sulphonylurea (SU) alone, biguanide (BG) alone or SU and BG combined. There were no clinically relevant differences in glycated haemoglobin (HbA1c) changes among the three subgroups in the dulaglutide group; in the glargine group, a numerically greater reduction was observed in combination with BG alone compared to the other two groups (SU alone and SU + BG). Weight loss was observed with dulaglutide in combination with BG alone or with SU + BG. The incidence of adverse events among subgroups was significantly different in the glargine group but not in the dulaglutide group. Incidence of hypoglycaemia was highest in combination with SU for both treatments. For patients with T2D, dulaglutide added to concomitant BG may be more likely to result in weight loss than dulaglutide added to concomitant SU.


Assuntos
Biguanidas/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Hipoglicemiantes/uso terapêutico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Insulina Glargina/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , Redução de Peso , Povo Asiático , Glicemia/metabolismo , Peso Corporal , Diabetes Mellitus Tipo 2/metabolismo , Quimioterapia Combinada , Feminino , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Hemoglobinas Glicadas/metabolismo , Humanos , Japão , Masculino , Pessoa de Meia-Idade
10.
Nihon Rinsho ; 73(2): 341-9, 2015 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-25764693

RESUMO

Wolfram syndrome(WFS: OMIM 222300) is a rare recessive neuro-endocrine degenerative disorder, known as DIDMOAD(Diabetes Insipidus, early-onset Diabetes Mellitus, Optic Atrophy and Deafness) syndrome. Most affected individuals carry recessive mutations in the Wolfram syndrome 1 gene(WFS1). The WFS1 protein is an endoplasmic reticulum(ER) embedded protein, which functions in ER calcium homeostasis and unfolded protein responses. Dysregulation of these cellular processes results in the development of ER stress, leading to apoptosis. In addition, abundantly present WFS1 protein in insulin secretory granules plays a role in the intra-granular acidification. However, the phenotypic pleiomorphism and molecular complexity of this disease limit the understanding of WFS. Here we review clinical features, molecular mechanisms and mutations of WFS1 gene that relate to this syndrome.


Assuntos
Proteínas de Membrana/genética , Síndrome de Wolfram/genética , Síndrome de Wolfram/fisiopatologia , Animais , Diabetes Mellitus/etiologia , Humanos , Camundongos , Camundongos Knockout/psicologia , Mutação
11.
Cardiovasc Diabetol ; 13: 65, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24678906

RESUMO

BACKGROUND: In recent years, several oral antidiabetic drugs with new mechanisms of action have become available, expanding the number of treatment options. Sodium/glucose cotransporter-2 (SGLT2) inhibitors are a new class of oral antidiabetic drugs with an insulin-independent mechanism promoting urinary glucose excretion. We report the results of a combined Phase 2 and 3 clinical study (Japic CTI-101349) of the SGLT2 inhibitor tofogliflozin (CSG452, RG7201) in Japanese patients with type 2 diabetes mellitus. METHODS: The efficacy and safety of tofogliflozin were assessed in this multicenter, placebo-controlled, randomized, double-blind parallel-group study involving 230 patients with type 2 diabetes mellitus with inadequate glycemic control on diet/exercise therapy. Between 30 October 2010 and 28 February 2012, patients at 33 centers were randomized to either placebo (n = 56) or tofogliflozin (10, 20, or 40 mg; n = 58 each) orally, once daily for 24 weeks. The primary efficacy endpoint was the change from baseline in HbA1c at week 24. RESULTS: Overall, 229 patients were included in the full analysis set (placebo: n = 56; tofogliflozin 10 mg: n = 57; tofogliflozin 20 and 40 mg: n = 58 each). The least squares (LS) mean change (95% confidence interval) from baseline in HbA1c at week 24 was -0.028% (-0.192 to 0.137) in the placebo group, compared with -0.797% (-0.960 to -0.634) in the tofogliflozin 10 mg group, -1.017% (-1.178 to -0.856) in the tofogliflozin 20 mg group, and -0.870% (-1.031 to -0.709) in the tofogliflozin 40 mg group (p < 0.0001 for the LS mean differences in all tofogliflozin groups vs placebo). There were also prominent decreases in fasting blood glucose, 2-h postprandial glucose, and body weight in all tofogliflozin groups compared with the placebo group. The main adverse events were hyperketonemia, ketonuria, and pollakiuria. The incidence of hypoglycemia was low. Furthermore, most adverse events were classified as mild or moderate in severity. CONCLUSIONS: Tofogliflozin 10, 20, or 40 mg administered once daily as monotherapy significantly decreased HbA1c and body weight, and was generally well tolerated in Japanese patients with type 2 diabetes mellitus. Phase 3 studies were recently completed and support the findings of this combined Phase 2 and 3 study. TRIAL REGISTRATION: This study was registered in the JAPIC clinical trials registry (ID: Japic CTI-101349).


Assuntos
Povo Asiático , Compostos Benzidrílicos/uso terapêutico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose , Adulto , Idoso , Povo Asiático/etnologia , Compostos Benzidrílicos/efeitos adversos , Compostos Benzidrílicos/farmacologia , Diabetes Mellitus Tipo 2/etnologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Glucosídeos/efeitos adversos , Glucosídeos/farmacologia , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Cetose/induzido quimicamente , Cetose/diagnóstico , Masculino , Pessoa de Meia-Idade , Transportador 2 de Glucose-Sódio/metabolismo , Resultado do Tratamento , Adulto Jovem
12.
Commun Biol ; 7(1): 527, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714733

RESUMO

Macrophages are versatile cells of the innate immune system that work by altering their pro- or anti-inflammatory features. Their dysregulation leads to inflammatory disorders such as inflammatory bowel disease. We show that macrophage-specific upregulation of the clock output gene and transcription factor E4BP4 reduces the severity of colitis in mice. RNA-sequencing and single-cell analyses of macrophages revealed that increased expression of E4BP4 leads to an overall increase in expression of anti-inflammatory genes including Il4ra with a concomitant reduction in pro-inflammatory gene expression. In contrast, knockout of E4BP4 in macrophages leads to increased proinflammatory gene expression and decreased expression of anti-inflammatory genes. ChIP-seq and ATAC-seq analyses further identified Il4ra as a target of E4BP4, which drives anti-inflammatory polarization in macrophages. Together, these results reveal a critical role for E4BP4 in regulating macrophage inflammatory phenotypes and resolving inflammatory bowel diseases.


Assuntos
Colite , Macrófagos , Animais , Macrófagos/imunologia , Macrófagos/metabolismo , Colite/genética , Colite/imunologia , Colite/metabolismo , Colite/patologia , Colite/induzido quimicamente , Camundongos , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Camundongos Knockout , Fenótipo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Índice de Gravidade de Doença , Masculino , Inflamação/genética , Inflamação/metabolismo
13.
Hum Mol Genet ; 20(7): 1274-84, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21199859

RESUMO

Wolfram syndrome is an autosomal recessive disorder characterized by juvenile-onset insulin-dependent diabetes mellitus and optic atrophy. The gene responsible for the syndrome (WFS1) encodes an endoplasmic reticulum (ER) resident transmembrane protein. The Wfs1-null mouse exhibits progressive insulin deficiency causing diabetes. Previous work suggested that the function of the WFS1 protein is connected to unfolded protein response and to intracellular Ca(2+) homeostasis. However, its precise molecular function in pancreatic ß-cells remains elusive. In our present study, immunofluorescent and electron-microscopic analyses revealed that WFS1 localizes not only to ER but also to secretory granules in pancreatic ß-cells. Intragranular acidification was assessed by measuring intracellular fluorescence intensity raised by the acidotrophic agent, 3-[2,4-dinitroanilino]-3'-amino-N-methyldipropyramine. Compared with wild-type ß-cells, there was a 32% reduction in the intensity in WFS1-deficient ß-cells, indicating the impairment of granular acidification. This phenotype may, at least partly, account for the evidence that Wfs1-null islets have impaired proinsulin processing, resulting in an increased circulating proinsulin level. Morphometric analysis using electron microscopy evidenced that the density of secretory granules attached to the plasma membrane was significantly reduced in Wfs1-null ß-cells relative to that in wild-type ß-cells. This may be relevant to the recent finding that granular acidification is required for the priming of secretory granules preceding exocytosis and may partly explain the fact that glucose-induced insulin secretion is profoundly impaired in young prediabetic Wfs1-null mice. These results thus provide new insights into the molecular mechanisms of ß-cell dysfunction in patients with Wolfram syndrome.


Assuntos
Retículo Endoplasmático/metabolismo , Exocitose/fisiologia , Células Secretoras de Insulina/metabolismo , Proteínas de Membrana/imunologia , Proinsulina/metabolismo , Vesículas Secretórias/metabolismo , Animais , Cálcio/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/ultraestrutura , Exocitose/efeitos dos fármacos , Glucose/farmacologia , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Humanos , Células Secretoras de Insulina/ultraestrutura , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Proinsulina/genética , Vesículas Secretórias/genética , Vesículas Secretórias/ultraestrutura , Edulcorantes/farmacologia , Síndrome de Wolfram/genética , Síndrome de Wolfram/metabolismo , Síndrome de Wolfram/patologia
14.
Biochem Biophys Res Commun ; 434(2): 370-5, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23567972

RESUMO

Aryl hydrocarbon receptor nuclear translocator (ARNT)/hypoxia inducible factor-1ß (HIF-1ß) has emerged as a potential determinant of pancreatic ß-cell dysfunction and type 2 diabetes in humans. An 82% reduction in Arnt expression was observed in islets from type 2 diabetic donors as compared to non-diabetic donors. However, few regulators of Arnt expression have been identified. Meanwhile, disruption of the clock components CLOCK and BMAL1 is known to result in hypoinsulinemia and diabetes, but the molecular details remain unclear. In this study, we identified a novel molecular connection between Arnt and two clock-controlled output genes, albumin D-element binding protein (Dbp) and E4 binding protein 4 (E4bp4). By conducting gene expression studies using the islets of Wfs1(-/-) A(y)/a mice that develop severe diabetes due to ß-cell apoptosis, we demonstrated clock-related gene expressions to be altered in the diabetic mice. Dbp mRNA decreased by 50%, E4bp4 mRNA increased by 50%, and Arnt mRNA decreased by 30% at Zeitgever Time (ZT) 12. Mouse pancreatic islets exhibited oscillations of clock gene expressions. E4BP4, a D-box negative regulator, oscillated anti-phase to DBP, a D-box positive regulator. We also found low-amplitude circadian expression of Arnt mRNA, which peaked at ZT4. Over-expression of DBP raised both mRNA and protein levels of ARNT in HEK293 and MIN6 cell lines. Arnt promoter-driven luciferase reporter assay in MIN6 cells revealed that DBP increased Arnt promoter activity by 2.5-fold and that E4BP4 competitively inhibited its activation. In addition, on ChIP assay, DBP and E4BP4 directly bound to D-box elements within the Arnt promoter in MIN6 cells. These results suggest that in mouse pancreatic islets mRNA expression of Arnt fluctuates significantly in a circadian manner and that the down-regulation of Dbp and up-regulation E4bp4 contribute to direct suppression of Arnt expression in diabetes.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Ritmo Circadiano , Proteínas de Ligação a DNA/metabolismo , Genes Reguladores , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Fatores de Transcrição/metabolismo , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Imunoprecipitação da Cromatina , Proteínas de Ligação a DNA/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Regulação da Expressão Gênica , Células HEK293 , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Ativação Transcricional
15.
Nihon Rinsho ; 71(11): 1936-40, 2013 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-24397162

RESUMO

Aging is a critical risk factor for impaired glucose tolerance and diabetes. In Japan, 8.9 million people are reported to have diabetes, and 37% of those are over the age of 70. In this review, we summarize the current evidence on how aging affects pancreatic beta cell function, beta cell mass, insulin secretion and insulin sensitivity. The pathogenesis of type 2 diabetes (T2DM) in aging is characterized by two major features: impaired insulin secretion and peripheral insulin resistance. Understanding the mechanism that lead to impaired glucose homeostasis and T2DM in the elderly will lead to development of novel treatments that will prevent or delay diabetes, substantially improve quality of life and ultimately increase overall life span.


Assuntos
Envelhecimento/metabolismo , Diabetes Mellitus Tipo 2/etiologia , Intolerância à Glucose/etiologia , Resistência à Insulina , Insulina/metabolismo , Envelhecimento/patologia , Animais , Diabetes Mellitus Tipo 2/prevenção & controle , Glucose/metabolismo , Intolerância à Glucose/prevenção & controle , Homeostase , Humanos , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/fisiologia , Oxirredução , Qualidade de Vida , Fatores de Risco
16.
FEBS Open Bio ; 13(8): 1405-1414, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37440664

RESUMO

Wolfram syndrome is a monogenic disease mainly caused by mutations in the WFS1 gene. Mutations in the WFS1 gene give rise to diabetes. Here, we characterized mutant WFS1 proteins by studying the stability of full-length wild-type (WT) WFS1, a missense mutant P724L, and two C-terminally truncated mutants, W837X and Y652X. We compared their stability by overexpressing them in MIN6 and HEK293T cells. The C-terminally truncated mutants W837X and Y652X are degraded more rapidly than the missense P724L mutant or wild-type WFS1 in MIN6 cells. In contrast, Y652X is more stable than WT or other mutant WFS1 proteins in HEK293T. In conclusion, we found that C-terminally truncated WFS1 mutants are selectively degraded in a cell type-specific manner.


Assuntos
Células Secretoras de Insulina , Síndrome de Wolfram , Humanos , Células HEK293 , Células Secretoras de Insulina/metabolismo , Mutação/genética , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Síndrome de Wolfram/genética , Síndrome de Wolfram/metabolismo
17.
J Diabetes Investig ; 14(1): 19-27, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36181414

RESUMO

AIMS/INTRODUCTION: Insulin stimulates translocation of glucose transporter 4 (GLUT4) from the perinuclear location to the plasma membrane. In the unstimulated state, intracellular vesicles containing GLUT4 are sequestered into specialized storage vesicles that have come to be known as the insulin-responsive compartment (IRC). The IRC is a functional compartment in the perinuclear region that is a target of the insulin signaling cascade, although its precise nature is unclear. Here, we report a novel molecular mechanism facilitating formation of the IRC. MATERIALS AND METHODS: We determined synaptosomal-associated protein of 29 kDa (SNAP29) by mass spectrometry to be an EH domain-containing protein 1 (EHD1)-binding protein. Then, its expression was confirmed by western blotting. Subcellular localization of SNAP29 was determined by immunofluorescent microscopy. Interactions between SNAP29 and syntaxins were determined by immunoprecipitation. We measured glucose uptake and GLUT4 translocation in 3T3-L1 adipocyte expressing SNAP29 or silencing SNAP29. RESULTS: We found SNAP29 to be localized in the perinuclear region and to show partial co-localization with GLUT4 under basal conditions. We also found that SNAP29 binds to syntaxin6, a Qc-SNARE, in adipocytes. In SNAP29-expressing cells, vesicles containing GLUT4 were observed to aggregate around the perinuclear region. In contrast, when SNAP29 was silenced, perinuclear GLUT4 vesicles were dispersed throughout the cytosol. Insulin-stimulated glucose uptake was inhibited in both SNAP29-expressing and SNAP29-silenced cells. CONCLUSIONS: These data suggest that SNAP29 sequesters and anchors GLUT4-containing vesicles in the perinuclear region, and might have a role in the biogenesis of the perinuclear IRC.


Assuntos
Proteínas de Transporte de Monossacarídeos , Proteínas SNARE , Humanos , Proteínas SNARE/metabolismo , Adipócitos/metabolismo , Insulina/metabolismo , Glucose/metabolismo , Proteínas Qc-SNARE/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Transporte Proteico/fisiologia , Proteínas de Transporte Vesicular/metabolismo , Proteínas Qb-SNARE/metabolismo
18.
Diabetol Int ; 14(4): 434-439, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37781469

RESUMO

Aims/introduction: Diabetic cardiomyopathy (DCM) is characterized predominantly by diastolic dysfunction. The multiple mechanisms underlying DCM include altered energy substrate utilization. Recent studies indicate that PPARα plays an important role in the pathogenesis of lipotoxic cardiomyopathy. Pemafibrate is known to be a selective PPARα modulator (SPPARMα). We thus investigated the effects of pemafibrate on cardiac diastolic function in patients with type 2 diabetes. Materials and methods: Seventeen patients with type 2 diabetes (T2D) and hypertriglyceridemia were screened and treated with pemafibrate at a dose of 0.2 mg/day for 8-16 weeks. Fourteen patients were eligible for analysis. Echocardiography was used for assessment of diastolic function. Early diastolic filling velocity (E), late atrial filling velocity (A) and the E/A ratio were included in this study. Peak early diastolic annular velocities (e') were also assessed using color tissue Doppler images. The primary endpoints were changes in the ratio of E to A (E/A), e', and the ratio of E to e' (E/e') from baseline. Results: Pemafibrate significantly increased average e' (7.24 ± 0.58 vs 7.94 ± 0.67, p = 0.019) and a significant reduction in E/e' (9.01 ± 0.94 vs 8.20 ± 0.91, p = 0.041). The increase in e' was significantly related to increases in fasting blood glucose (r = 0.607, p = 0.021) and non-esterified fatty acid (r = 0.592, p = 0.026). Conclusion: Pemafibrate improved diastolic function in patients with T2D and hypertriglyceridemia, suggesting that PPARα activation by pemafibrate prevents the development of DCM at an early stage.

19.
Front Pharmacol ; 14: 1167934, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251332

RESUMO

Hachimijiogan (HJG) has originally been used to ameliorate a variety of symptoms associated with low ambient temperatures. However, its pharmacological action in metabolic organs remains unclear. We hypothesized that HJG may modulate metabolic function and have a potential therapeutic application to metabolic diseases. To test this hypothesis, we investigated metabolic action of HJG in mice. Male C57BL/6J mice chronically administered with HJG showed a reduction in adipocyte size with increased transcription of beige adipocyte-related genes in subcutaneous white adipose tissue. HJG-mixed high-fat diet (HFD)-fed mice showed alleviation of HFD-induced weight gain, adipocyte hypertrophy, liver steatosis with a significant reduction in circulating leptin and Fibroblast growth factor 21 despite no changes in food intake or oxygen consumption. Feeding an HJG-mixed HFD following 4-weeks of HFD feeding, while a limited effect on body weight, improved insulin sensitivity with a reversal of decreased circulating adiponectin. In addition, HJG improved insulin sensitivity in the leptin-deficient mice without significant effects on body weight. Treatment with n-butanol soluble extracts of HJG potentiated transcription of Uncoupling protein 1 mediated by ß3-adrenergic agonism in 3T3L1 adipocytes. These findings provide evidence that HJG modulates adipocyte function and may exert preventive or therapeutic effects against obesity and insulin resistance.

20.
Nurs Health Sci ; 14(2): 197-203, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22435780

RESUMO

The consumption of meat products is considered to be a feasible solution to prevent anemia, which is a critical health problem. The present study assessed hematological parameters and the prevalence of anemia in Japanese children and adolescents, and examined the association with the frequency of meat intake. Data from the Shunan Children Health Cohort Study were analyzed. The participants included male and female residents, 3373 children (aged 10-11 years), and 3085 adolescents (aged 13-14 years). The frequency of meat intake was determined with a questionnaire, and blood samples were analyzed. Anemia was defined according to the criteria of the World Health Organization. The prevalence of anemia in children was 3.6% and 2.5% in girls and boys, respectively, and in adolescents, it was 4.5% in girls and 0.8% in boys. The frequency of meat intake did not show a positive association with the hematological indices or the prevalence of anemia. These results suggest that the promotion of meat consumption is not an effective strategy to decrease anemia, and that other approaches are necessary to prevent anemia in this population.


Assuntos
Anemia/epidemiologia , Dieta/estatística & dados numéricos , Carne , Adolescente , Criança , Estudos Transversais , Registros de Dieta , Feminino , Humanos , Japão/epidemiologia , Masculino , Prevalência
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