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1.
Molecules ; 26(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207664

RESUMO

Plant-derived phytochemicals have been interested in as nutraceuticals for preventing the onset and progress of diabetes mellitus and its serious complications in recent years. Moringa oleifera Lam. is used in vegetables and in herbal medicine for its health-promoting properties against various diseases including diabetes mellitus. This study aimed to examine an effect of Moringa oleifera on diabetic hyperglycemia and dyslipidemia by meta-analyzing the current evidence of diabetic rodent models. Peer-reviewed studies written in English from two databases, PubMed and Embase, were searched to 30 April 2021. Studies reporting blood glucose or lipid levels in diabetic rodents with and without receiving extracts of Moringa oleifera were included. Forty-four studies enrolling 349 diabetic rodents treated with extracts of Moringa oleifera and 350 diabetic controls reported blood glucose levels. The pooled effect size was -3.92 (95% CI: -4.65 to -3.19) with a substantial heterogeneity. This effect was likely to be, at least in part, modified by the type of diabetic models. Moreover, diabetic hypertriglyceridemia and hypercholesterolemia were also significantly improved in diabetic rodent models treated with Moringa oleifera.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Suplementos Nutricionais , Moringa oleifera/química , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Extratos Vegetais/química , Plantas Medicinais/química
2.
Nihon Koshu Eisei Zasshi ; 68(2): 105-117, 2021 Feb 26.
Artigo em Japonês | MEDLINE | ID: mdl-33390509

RESUMO

Objective Obesity associated with an increased consumption of ultra-processed foods (UPF) has been reported by studies abroad using the NOVA food classification system, an international framework for classifying food according to the degree of processing. However, no such study has been conducted in Japan. In this study, we evaluated the association between UPF consumption, nutrient intake, and obesity using the NOVA system.Method In September 2017, we conducted a survey using a questionnaire of patients who had attended routine health checkups in Manazuru Town, Kanagawa Prefecture and collected their three-day dietary records as well as medical examination results. The final analysis included 169 patients (66 men, 103 women). Food consumed by the respondents were classified into four groups of NOVA systems. The dietary share of UPF (UPF energy ratio) was compared to total energy intake (except alcoholic beverages and eating out). Nutrient intake and obesity risk were compared across the UPF energy ratio tertile (low, middle, and high intake). Covariance and logistic regression analysis were conducted and adjusted based on age, sex, household structure, education, income, and total energy intake (except energy-providing nutrients, macronutrients, and protein intake per body weight) to analyze the association between UPF consumption and nutrient intake. Finally, for obesity, we adjusted for physical activity and smoking status using a similar analysis of the relationship between UPF consumption and energy providing nutrients and macronutrients.Result Approximately 75% of patients investigated were older than 65 years. The average (standard deviation) UPF energy ratio was 29.7% (15.0). There were no significant differences in socioeconomic status among groups according to the UPF energy ratio. The high-UPF group had a significantly greater total energy intake. However, the protein energy ratio, protein intake per body weight, dietary fiber, and vitamins A, E, K, B1, B6, C, niacin, folic acid, potassium, magnesium, and iron intake were significantly lower in the high-UPF group. Moreover, the high-UPF group had a significantly higher BMI. The odds ratio for obesity was higher (4.51[1.50-13.57]) in the high-UPF group than in the low-UPF group (1.00).Conclusion Those who consumed more UPF had lower protein intake and suffered from multiple vitamin and mineral deficiencies. Furthermore, their energy intake was greater, and the odds ratio for obesity was significantly higher. It has been suggested that excessive UPF consumption warrants further attention.


Assuntos
Dieta/estatística & dados numéricos , Ingestão de Alimentos/fisiologia , Fast Foods/efeitos adversos , Fast Foods/estatística & dados numéricos , Manipulação de Alimentos , Programas Nacionais de Saúde , Fenômenos Fisiológicos da Nutrição/fisiologia , Obesidade/epidemiologia , Obesidade/etiologia , Adulto , Idoso , Proteínas Alimentares , Ingestão de Energia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Minerais , Inquéritos e Questionários , Vitaminas , Adulto Jovem
3.
Molecules ; 23(4)2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29642387

RESUMO

In a rapid increase in cases of diabetes mellitus worldwide, there has been interested in the use of plant-derived polyphenols as nutraceuticals to prevent the onset and progression of diabetes mellitus and its associated complications. Aspalathus linearis, commonly known as rooibos, is a rich source of uncommon glycosylated plant polyphenols with various critical health-promoting properties, including the prevention and treatment of diabetes mellitus (DM). This study aimed to examine these effects by meta-analyzing the current evidence in diabetic rodent models. Peer-reviewed studies written in English from two databases, PubMed and Embase, were searched up to 28 February 2018. Studies reporting blood glucose levels in diabetic rodents with and without receiving rooibos extracts or their major phenolic compounds are included. Twelve studies enrolling 88 diabetic rodents treated with rooibos extracts or their polyphenols and 85 diabetic control males reported blood glucose levels. The pooled effect size was -0.89 (95% CI: -1.44 to -0.35) with a substantial heterogeneity (I² = 67.0%). This effect was likely to be modified by type of rooibos extracts and their polyphenols and treatment period. Blood glucose levels were significantly lower in diabetic rodent models treated with the phenolic compound rich in rooibos extracts, PPAG.


Assuntos
Aspalathus/química , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Diabetes Mellitus Experimental/metabolismo , Humanos , Masculino , Camundongos , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/administração & dosagem , Polifenóis/química , Polifenóis/farmacologia , Ratos , Tamanho da Amostra
4.
PLoS One ; 11(7): e0159375, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27467521

RESUMO

ELOVL family member 6, elongation of very long chain fatty acids (Elovl6) is a microsomal enzyme, which regulates the elongation of C12-16 saturated and monounsaturated fatty acids. Elovl6 has been shown to be associated with various pathophysiologies including insulin resistance, atherosclerosis, and non-alcoholic steatohepatitis. To investigate a potential role of Elovl6 during bone development, we here examined a skeletal phenotype of Elovl6 knockout (Elovl6-/-) mice. The Elovl6-/- skeleton was smaller than that of controls, but exhibited no obvious patterning defects. Histological analysis revealed a reduced length of proliferating and an elongated length of hypertrophic chondrocyte layer, and decreased trabecular bone in Elovl6-/- mice compared with controls. These results were presumably due to a modest decrease in chondrocyte proliferation and accelerated differentiation of cells of the chondrocyte lineage. Consistent with the increased length of the hypertrophic chondrocyte layer in Elovl6-/- mice, Collagen10α1 was identified as one of the most affected genes by ablation of Elovl6 in chondrocytes. Furthermore, this elevated expression of Collagen10α1 of Elovl6-null chondrocytes was likely associated with increased levels of Foxa2/a3 and Mef2c mRNA expression. Relative increases in protein levels of nuclear Foxa2 and cytoplasmic histone deacethylase 4/5/7 were also observed in Elovl6 knockdown cells of the chondrocyte lineage. Collectively, our data suggest that Elovl6 plays a critical role for proper development of embryonic growth plate.


Assuntos
Acetiltransferases/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Condrócitos/citologia , Lâmina de Crescimento/crescimento & desenvolvimento , Acetiltransferases/genética , Animais , Condrócitos/metabolismo , Elongases de Ácidos Graxos , Camundongos , Camundongos Knockout , Osteoblastos/metabolismo
5.
Endocrinology ; 155(12): 4706-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25233440

RESUMO

Transcriptional regulation of metabolic genes in the liver is the key to maintaining systemic energy homeostasis during starvation. The membrane-bound transcription factor cAMP-responsive element-binding protein 3-like 3 (CREB3L3) has been reported to be activated during fasting and to regulate triglyceride metabolism. Here, we show that CREB3L3 confers a wide spectrum of metabolic responses to starvation in vivo. Adenoviral and transgenic overexpression of nuclear CREB3L3 induced systemic lipolysis, hepatic ketogenesis, and insulin sensitivity with increased energy expenditure, leading to marked reduction in body weight, plasma lipid levels, and glucose levels. CREB3L3 overexpression activated gene expression levels and plasma levels of antidiabetic hormones, including fibroblast growth factor 21 and IGF-binding protein 2. Amelioration of diabetes by hepatic activation of CREB3L3 was also observed in several types of diabetic obese mice. Nuclear CREB3L3 mutually activates the peroxisome proliferator-activated receptor (PPAR) α promoter in an autoloop fashion and is crucial for the ligand transactivation of PPARα by interacting with its transcriptional regulator, peroxisome proliferator-activated receptor gamma coactivator-1α. CREB3L3 directly and indirectly controls fibroblast growth factor 21 expression and its plasma level, which contributes at least partially to the catabolic effects of CREB3L3 on systemic energy homeostasis in the entire body. Therefore, CREB3L3 is a therapeutic target for obesity and diabetes.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Diabetes Mellitus Experimental/metabolismo , Metabolismo Energético , Jejum/metabolismo , Fígado/metabolismo , Animais , Peso Corporal , Ingestão de Alimentos , Fatores de Crescimento de Fibroblastos/metabolismo , Privação de Alimentos/fisiologia , Expressão Gênica , Homeostase , Resistência à Insulina , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/etiologia , Obesidade/metabolismo , PPAR alfa/metabolismo , Inanição/metabolismo
6.
Biochem Biophys Res Commun ; 450(1): 318-23, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24938128

RESUMO

ELOVL family member 6, elongation of very long-chain fatty acids (Elovl6) is a microsomal enzyme that regulates the elongation of C12-16 saturated and monounsaturated fatty acids and is related to the development of obesity-induced insulin resistance via the modification of the fatty acid composition. In this study, we investigated the role of systemic Elovl6 in the pancreatic islet and ß-cell function. Elovl6 is expressed in both islets and ß-cell lines. In mice fed with chow, islets of the Elovl6(-/-) mice displayed normal architecture and ß-cell mass compared with those of the wild-type mice. However, when fed a high-fat, high-sucrose (HFHS) diet, the islet hypertrophy in response to insulin resistance observed in normal mice was attenuated and glucose-stimulated insulin secretion (GSIS) increased in the islets of Elovl6(-/-) mice compared with those of the wild-type mice. Enhanced GSIS in the HFHS Elovl6(-/-) islets was associated with an increased ATP/ADP ratio and the suppression of ATF-3 expression. Our findings suggest that Elovl6 could be involved in insulin secretory capacity per ß-cell and diabetes.


Assuntos
Acetiltransferases/metabolismo , Gorduras na Dieta/efeitos adversos , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Obesidade/metabolismo , Obesidade/patologia , Animais , Células Cultivadas , Elongases de Ácidos Graxos , Feminino , Resistência à Insulina , Secreção de Insulina , Masculino , Camundongos , Camundongos Knockout , Obesidade/etiologia , Especificidade de Órgãos , Distribuição Tecidual
7.
Endocrinology ; 154(10): 3577-88, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23885019

RESUMO

Transcription factor E3 (TFE3) is a transcription factor that binds to E-box motifs and promotes energy metabolism-related genes. We previously reported that TFE3 directly binds to the insulin receptor substrate-2 promoter in the liver, resulting in increased insulin response. However, the role of TFE3 in other tissues remains unclear. In this study, we generated adipose-specific TFE3 transgenic (aP2-TFE3 Tg) mice. These mice had a higher weight of white adipose tissue (WAT) and brown adipose tissue than wild-type (WT) mice under fasting conditions. Lipase activity in the WAT in these mice was lower than that in the WT mice. The mRNA level of adipose triglyceride lipase (ATGL), the rate-limiting enzyme for adipocyte lipolysis, was significantly decreased in aP2-TFE3 Tg mice. The expression of Foxo1, which directly activates ATGL expression, was also suppressed in transgenic mice. Promoter analysis confirmed that TFE3 suppressed promoter activities of the ATGL gene. In contrast, G0S2 and Perilipin1, which attenuate ATGL activity, were higher in transgenic mice than in WT mice. These results indicated that the decrease in lipase activity in adipose tissues was due to a decrease in ATGL expression and suppression of ATGL activity. We also showed that thermogenesis was suppressed in aP2-TFE3 Tg mice. The decrease in lipolysis in WAT of aP2-TFE3 Tg mice inhibited the supply of fatty acids to brown adipose tissue, resulting in the inhibition of the expression of thermogenesis-related genes such as UCP1. Our data provide new evidence that TFE3 regulates lipid metabolism by controlling the gene expression related to lipolysis and thermogenesis in adipose tissue.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Regulação para Baixo , Lipólise , Obesidade/metabolismo , Termogênese , Células 3T3-L1 , Adipogenia , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/enzimologia , Tecido Adiposo Branco/patologia , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/biossíntese , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Lipase/genética , Lipase/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Obesidade/enzimologia , Obesidade/patologia , Perilipina-1 , Fosfoproteínas/biossíntese , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Proteína Desacopladora 1
8.
Cell Biochem Biophys ; 66(1): 23-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22821549

RESUMO

The receptor for parathyroid hormone (PTH) and PTH-related peptide (PTH1R) belongs to the class II G protein-coupled receptor superfamily. The calpain small subunit encoded by the gene Capns1 is the second protein and the first enzyme identified by a yeast two-hybrid screen using the intracellular C-terminal tail of the rat PTH1R. The calpain regulatory small subunit forms a heterodimer with the calpain large catalytic subunit and modulates various cellular functions as a cysteine protease. To investigate a physiological role of the calpain small subunit in cells of the osteoblast lineage, we generated osteoblast-specific Capns1 knockout mouse models and characterized their bone phenotype. Molecular mechanisms by which calpain modulates cell proliferation of the osteoblast lineage were further examined in vitro. Moreover, we utilized the mutant mice as a disease model of osteoporosis accompanied with impaired bone resorptive function and suggested a possible clinical translation of our basic research finding.


Assuntos
Osso e Ossos/metabolismo , Calpaína/metabolismo , Osteoblastos/metabolismo , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Aumento de Peso , Animais , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Osso e Ossos/patologia , Calpaína/genética , Linhagem da Célula , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Intolerância à Glucose/induzido quimicamente , Intolerância à Glucose/patologia , Camundongos , Camundongos Knockout , Osteoblastos/patologia , Osteocalcina/metabolismo , Osteoporose , Regiões Promotoras Genéticas , Receptor Tipo 1 de Hormônio Paratireóideo/genética , Transdução de Sinais , Fator de Transcrição Sp7 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Biochem Biophys Res Commun ; 430(2): 664-9, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23211595

RESUMO

Transcription factor E3 (TFE3) belongs to a basic helix-loop-helix family, and is involved in the biology of osteoclasts, melanocytes and their malignancies. We previously reported the metabolic effects of TFE3 on insulin in the liver and skeletal muscles in animal models. In the present study, we explored a novel role for TFE3 in a skeletal muscle cell line. When TFE3 was overexpressed in C2C12 myoblasts by adenovirus before induction of differentiation, myogenic differentiation of C2C12 cells was significantly inhibited. Adenovirus-mediated TFE3 overexpression also suppressed the gene expression of muscle regulatory factors (MRFs), such as MyoD and myogenin, during C2C12 differentiation. In contrast, knockdown of TFE3 using adenovirus encoding short-hairpin RNAi specific for TFE3 dramatically promoted myoblast differentiation associated with significantly increased expression of MRFs. Consistent with these findings, promoter analyses via luciferase reporter assay and electrophoretic mobility shift assay suggested that TFE3 negatively regulated myogenin promoter activity by direct binding to an E-box, E2, in the myogenin promoter. These findings indicated that TFE3 has a regulatory role in myoblast differentiation, and that transcriptional suppression of myogenin expression may be part of the mechanism of action.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Diferenciação Celular/genética , Regulação da Expressão Gênica , Mioblastos/citologia , Miogenina/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Linhagem Celular , Regulação para Baixo , Técnicas de Silenciamento de Genes , Camundongos , Proteína MyoD/metabolismo , Fator Regulador Miogênico 5/metabolismo
10.
Hepatology ; 56(6): 2199-208, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22753171

RESUMO

UNLABELLED: Nonalcoholic steatohepatitis (NASH) is associated with obesity and type 2 diabetes, and an increased risk for liver cirrhosis and cancer. ELOVL family member 6, elongation of very long chain fatty acids (Elovl6), is a microsomal enzyme that regulates the elongation of C12-16 saturated and monounsaturated fatty acids (FAs). We have shown previously that Elovl6 is a major target for sterol regulatory element binding proteins in the liver and that it plays a critical role in the development of obesity-induced insulin resistance by modifying FA composition. To further investigate the role of Elovl6 in the development of NASH and its underlying mechanism, we used three independent mouse models with loss or gain of function of Elovl6, and human liver samples isolated from patients with NASH. Our results demonstrate that (1) Elovl6 is a critical modulator for atherogenic high-fat diet-induced inflammation, oxidative stress, and fibrosis in the liver; (2) Elovl6 expression is positively correlated with severity of hepatosteatosis and liver injury in NASH patients; and (3) deletion of Elovl6 reduces palmitate-induced activation of the NLR family pyrin domain-containing 3 inflammasome; this could be at least one of the underlying mechanisms by which Elovl6 modulates the progress of NASH. CONCLUSION: Hepatic long-chain fatty acid composition is a novel determinant in NASH development, and Elovl6 could be a potential therapeutic target for the prevention and treatment of NASH.


Assuntos
Acetiltransferases/genética , Acetiltransferases/metabolismo , Ácidos Graxos/metabolismo , Fígado Gorduroso/enzimologia , Perfilação da Expressão Gênica , Hepatócitos/metabolismo , Inflamassomos/metabolismo , Análise de Variância , Animais , Glicemia/metabolismo , Proteínas de Transporte/metabolismo , Colesterol/metabolismo , Dieta Aterogênica , Dieta Hiperlipídica , Modelos Animais de Doenças , Elongases de Ácidos Graxos , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Humanos , Insulina/sangue , Resistência à Insulina , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Hepatopatia Gordurosa não Alcoólica , Estresse Oxidativo , Ácido Palmítico/metabolismo , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença , Fatores de Transcrição/genética , Triglicerídeos/metabolismo
11.
Biochem Biophys Res Commun ; 409(2): 235-40, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21569760

RESUMO

The ubiquitously expressed Calpains 1 and 2 belong to a family of calcium-dependent intracellular cysteine proteases. Both calpains are heterodimers consisting of a large subunit and a small regulatory subunit encoded by the gene Capns1. To investigate a role for the calpain small subunit in cells of the osteoblast lineage in vivo, we previously generated osteoblast-specific Capns1 knockout mice and characterized their bone phenotype. In this study, we further examined effects of low calcium and high fat diets on their bone, fat, and glucose homeostasis. Osteoblast-specific Capns1 knockout mice showed significantly reduced serum levels of total and uncarboxylated osteocalcin, and this was presumably due to their impaired bone formation and bone resorption. The reduced bone resorptive function of the mutant mice was also significant under a low calcium diet. Thus, these results suggest that reduced uncarboxylated osteocalcin levels of mutant mice were, at least in part, due to their osteoporotic bone with impaired bone resorptive function. Interestingly, unlike osteocalcin knockout mice, mutant mice on a normal chow diet were leaner than control littermates; this was likely due to their reduced food intake and overall lower energy homeostasis. To test this hypothesis, we next provided mutant mice with a high fat diet and further examined an effect of their reduced uncarboxylated osteocalcin levels on body composition and glucose metabolism. The average mean body weight of mutant mice became indistinguishable with that of controls after 2 weeks on a high fat diet, and continued to show an upward trend, at least, up to 6weeks. Moreover, mutant mice on a high fat diet exhibited a significant increase in serum levels of leptin and resistin, adipocyte-specific adipokines, and developed impaired glucose tolerance. Collectively, mice with osteoporosis and reduced bone resorptive function showed reduced serum uncarboxylated osteocalcin levels and were susceptible to increase body adiposity and develop impaired glucose tolerance under a high fat diet.


Assuntos
Calpaína/genética , Gorduras na Dieta/administração & dosagem , Glucose/metabolismo , Osteoblastos/metabolismo , Magreza/metabolismo , Adiposidade/efeitos dos fármacos , Adiposidade/genética , Animais , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Cálcio da Dieta/administração & dosagem , Dieta , Deleção de Genes , Teste de Tolerância a Glucose , Camundongos , Camundongos Knockout , Osteocalcina/sangue , Magreza/sangue , Magreza/genética
12.
Calcif Tissue Int ; 89(1): 36-42, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21544553

RESUMO

The ubiquitously expressed calpains-1 and -2 belong to a family of calcium-dependent intracellular cysteine proteases. Both calpains are heterodimers consisting of a large catalytic subunit and a small regulatory subunit encoded by the gene Capn4. Ablation of the calpain small subunit eliminates calpain activity and leads to embryonic lethality. We previously created osteoblast-specific Capn4 knockout mice to investigate a physiological role for the calpain small subunit in cells of the osteoblast lineage. Deletion of Capn4 reduced trabecular and cortical bone, mainly due to impaired proliferation and differentiation of cells of the osteoblast lineage. To further investigate an underlining mechanism by which osteoblast-specific Capn4 knockout mice develop an osteoporotic bone phenotype, we established osteoblastic cell lines stably expressing either control or Capn4 RNA interference for this study. Capn4 knockdown cells showed reduced cell proliferation, accumulation of total and phosphorylated cyclin-dependent kinase inhibitor 1B (p27(Kip1)) on serine 10, and reduced phosphorylation of retinoblastoma protein on threonine 821. Moreover, ablation of Capn4 increased 27 ( Kip1 ) mRNA levels, likely due to stabilized binding of Akt to protein phosphatase 2A, which presumably results in reduced phosphorylation of Akt on S473 and forkhead Box O (FoxO) 3A on T32. Collectively, calpain regulates cell proliferative function by modulating both transcription and degradation of p27(Kip1) in osteoblasts. In conclusion, calpain is a critical modulator for regulation of p27(Kip1) in cells of the osteoblast lineage.


Assuntos
Calpaína/fisiologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Osteoblastos/metabolismo , Animais , Calpaína/metabolismo , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p27/genética , Camundongos , Camundongos Knockout , Interferência de RNA , RNA Mensageiro/metabolismo , Transcrição Gênica
13.
Mol Cell Biol ; 30(11): 2799-810, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20368361

RESUMO

Calpains are calcium-dependent intracellular cysteine proteases, which include ubiquitously expressed mu- and m-calpains. Both calpains are heterodimers consisting of a large catalytic subunit and a small regulatory subunit. The calpain small subunit encoded by the gene Capn4 directly binds to the intracellular C-terminal tail of the receptor for the parathyroid hormone (PTH) and PTH-related peptide and modulates cellular functions in cells of the osteoblast lineage in vitro and in vivo. To investigate a physiological role of the calpain small subunit in cells of the chondrocyte lineage, we generated chondrocyte-specific Capn4 knockout mice. Mutant embryos had reduced chondrocyte proliferation and differentiation in embryonic growth plates compared with control littermates. In vitro analysis further revealed that deletion of Capn4 in cells of the chondrocyte lineage correlated with impaired cell cycle progression at the G(1)/S transition, reduced cyclin D gene transcription, and accumulated cell cycle proteins known as calpain substrates. Moreover, silencing of p27(Kip1) rescued an impaired cell growth phenotype in Capn4 knockdown cells, and reintroducing the calpain small subunit partially normalized cell growth and accumulated cyclin D protein levels in a dose-dependent manner. Collectively, our findings suggest that the calpain small subunit is essential for proper chondrocyte functions in embryonic growth plates.


Assuntos
Calpaína/genética , Diferenciação Celular/fisiologia , Linhagem da Célula , Proliferação de Células , Condrócitos/fisiologia , Deleção de Genes , Animais , Biomarcadores/metabolismo , Calpaína/metabolismo , Ciclo Celular/fisiologia , Células Cultivadas , Condrócitos/citologia , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Lâmina de Crescimento/citologia , Lâmina de Crescimento/fisiologia , Camundongos , Camundongos Knockout , Hormônio Paratireóideo/genética , Hormônio Paratireóideo/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Gravidez , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Fator de Crescimento Transformador beta/genética
15.
J Biol Chem ; 283(30): 21002-10, 2008 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-18515801

RESUMO

Calpains are intracellular cysteine proteases, which include widely expressed mu- and m-calpains (1). Both mu-calpains and m-calpains are heterodimers consisting of a large catalytic subunit and a small regulatory subunit. The calpain small subunit encoded by the gene Capn4 directly binds to the intracellular C-terminal tail (C-tail) of the receptor for parathyroid hormone and parathyroid hormone-related peptide and modulates its cellular functions in osteoblasts in vitro (2). To investigate a potential role of the calpain small subunit in osteoblasts in vivo, we generated osteoblast-specific Capn4 knock-out mice using the Cre-LoxP system (3). Mutant mice had smaller bodies with shorter limbs, reduced trabecular bone with thinner cortices, and decreased osteoblast number. In vitro analysis confirmed that deletion of Capn4 in osteoblasts severely affected multiple osteoblast functions including proliferation, differentiation, and matrix mineralization. Collectively, our findings provide the first in vivo demonstration that the calpain small subunit is essential for proper osteoblast activity and bone remodeling.


Assuntos
Osso e Ossos/metabolismo , Calpaína/química , Osteoblastos/citologia , Animais , Remodelação Óssea , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Deleção de Genes , Camundongos , Modelos Biológicos , Osteoblastos/metabolismo , Hormônio Paratireóideo/metabolismo , Estrutura Terciária de Proteína , Tomografia Computadorizada por Raios X/métodos
16.
Br J Haematol ; 139(3): 458-63, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17868046

RESUMO

Chronic graft-versus-host disease (GVHD) is the most common cause of poor outcomes after haematopoietic stem cell transplantation (HSCT), while the pathophysiology of chronic GVHD remains poorly understood. As both chronic GVHD and autoimmune disease share clinical features, we speculated that autoimmune disease-related genes might be candidate chronic GVHD-related genes. Recent large-scale cohort studies showed that Fc receptor-like 3 gene (FCRL3) single nucleotide polymorphism (SNP) and peptidylarginine deiminases citrullinating enzymes 4 gene (PADI4) haplotype were associated with autoimmune disease. The present study investigated the association between polymorphisms of these two genes and the incidence of chronic GVHD. We analysed 123 cases of Japanese human leucocyte antigen-matched sibling recipients and their donors who underwent HSCT. Although PADI4, which is the rheumatoid arthritis-specific related gene, was not associated with the occurrence of chronic GVHD, the recipient FCRL3-169C/C genotype was significantly less frequent in chronic GVHD patients than in those without chronic GVHD (P = 0.0086). There was no relationship between FCRL3 polymorphism and acute GVHD. As FCRL3 is expressed by B cells and might have an important role in immunoregulation, this significant protective genetic effect raises the question of whether FCRL3 might also be involved in the pathogenesis of chronic GVHD.


Assuntos
Doenças Autoimunes/genética , Doença Enxerto-Hospedeiro/genética , Polimorfismo Genético , Adolescente , Adulto , Doença Crônica , Feminino , Frequência do Gene , Predisposição Genética para Doença , Haplótipos , Humanos , Hidrolases/genética , Masculino , Pessoa de Meia-Idade , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas , Receptores Imunológicos/genética , Estudos Retrospectivos , Fatores de Risco
17.
Br J Haematol ; 138(5): 624-31, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17686056

RESUMO

The Dickkopf-1 (DKK1) gene product is an extracellular Wnt inhibitor. Hypermethylation of the DKK1 promoter results in transcriptional silencing and may play an important role in cancer development. Here, we investigated hypermethylation of the DKK1 promoter in patients with acute myeloid leukaemia (AML), especially core-binding factor (CBF) leukaemia. The methylation status of DKK1 was analysed using methylation-specific polymerase chain reaction in 47 patients with AML. DKK1 methylation was found in 14 (29.8%) patients, and more frequently in those with CBF leukaemia (6 of 12 patients), than in those with acute promyelocytic leukaemia (APL) (0 of 6 patients) (P = 0.03). In contrast, Wnt inhibitory factor-1 methylation was found in APL (4 of 6 patients) but not in CBF leukaemia (0 of 12 patients) (P = 0.001). Multivariate analyses suggested that DKK1 methylation was a risk factor for poorer overall survival. Sequential analysis using four paired samples obtained at diagnosis and relapse suggested that DKK1 methylation was involved in the progression of leukaemia. Therefore, DKK1 methylation may be involved in leukaemogenesis, especially in CBF leukaemia, and may be a useful prognostic marker in AML.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Peptídeos e Proteínas de Sinalização Intercelular/genética , Leucemia Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Células da Medula Óssea/metabolismo , Fatores de Ligação ao Core/metabolismo , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Leucemia Mieloide/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Prognóstico , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Análise de Sobrevida , Células Tumorais Cultivadas
18.
Metabolism ; 56(9): 1187-91, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17697860

RESUMO

The serum lipoprotein(a) [Lp(a)] concentration is under genetic control, and most humans have values lower than 30 mg/dL. Subjects with markedly elevated serum Lp(a) concentrations, that is, > or =100 mg/dL, are rarely encountered, and these subjects have not yet been fully characterized from the clinical point of view. In the present investigation, we studied a total of 223 subjects, comprising 123 males and 100 females, with serum Lp(a) values of more than 100 mg/dL. Many of these subjects had a variety of underlying diseases, including metabolic disorders, renal diseases, and hypertension. We focused our attention on the patients with metabolic disorders, namely, familial hypercholesterolemia (FH), primary non-FH hypercholesterolemia (HC), and type 2 diabetes mellitus (DM), and conducted a comparative study of the patients of these 3 disease groups with the corresponding disease controls with serum Lp(a) levels of less than 30 mg/dL, a presumed high normal value. The frequency of markedly elevated serum Lp(a) levels in the general population has not been reported previously. We determined the frequencies in a consecutive series of patients at our Diabetes and Lipid Outpatient Clinic; the results revealed that the frequencies were 6.4% (8/125), 2.6% (6/232), and 0.9% (3/352) in patients with FH, HC, and type 2 DM, respectively. In an attempt to further demonstrate the impact of markedly elevated serum Lp(a) concentrations on the risk of coronary heart disease (CHD), we compared the prevalence of CHD among the study subjects with that among the corresponding disease controls. The results revealed a significantly higher CHD prevalence in the study subjects of all the 3 groups as compared with that in the corresponding disease controls: the odds ratios of a markedly elevated serum Lp(a) level were 5.429 (95% confidence interval [CI], 1.353-21.782), 8.243 (95% CI, 2.793-24.327), and 5.981 (95% CI, 2.530-14.139) for FH, HC, and type 2 DM, respectively. In the present study, we examined some characteristics of this rare population of subjects with markedly elevated serum Lp(a) levels and demonstrated a very high prevalence of CHD among these patients with FH, HC, and type 2 DM, strongly suggesting the significance of Lp(a) as a risk factor for CHD.


Assuntos
Doença das Coronárias/sangue , Doença das Coronárias/etiologia , Lipoproteína(a)/sangue , Idoso , Doença das Coronárias/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Hipercolesterolemia/sangue , Hiperlipoproteinemia Tipo II/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
19.
Int J Hematol ; 86(5): 422-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18192111

RESUMO

Mutations in the fms-like tyrosine kinase 3 (FLT3) gene containing an internal tandem duplication (FLT3/ITD) or mutations in the nucleophosmin 1 gene (NPM1) are thought to be prognostic indicators in acute myeloid leukemia (AML). Previous studies suggested that FLT3/ITD mutation indicates a poor prognosis and that NPM1 mutation indicates a more favorable one, but these studies were often performed with selected patient populations. We investigated the clinical significance of these mutations at our institution with an unselected group of patients with newly diagnosed AML. This group included patients > or =60 years old and those with a poor performance status. Using polymerase chain reaction and sequencing analyses, we detected FLT3/ITD mutations in 12 patients (20.0%) and NPM1 mutations in 7 patients (11.7%) among a group of 60 patients. There was a nonsignificant trend for FLT3/ITD mutation to be associated with a poorer predicted overall survival (OS) probability in this population. In contrast, OS was significantly higher in patients with wild-type NPM1 than in patients with NPM1 mutation, both for all AML patients and for AML patients with a normal karyotype. In this general and unselected AML patient population, NPM1 mutation was not a prognostic indicator of a favorable outcome.


Assuntos
Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Mutação , Proteínas Nucleares/genética , Tirosina Quinase 3 Semelhante a fms/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nucleofosmina , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Taxa de Sobrevida
20.
Tokai J Exp Clin Med ; 32(4): 131-5, 2007 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-21318952

RESUMO

OBJECTIVE: The Wnt/ß;-catenin signaling pathway is important in the pathogenesis of hematological malignancies. Wnt inhibitory factor-1 (WIF-1) is a negative regulator of Wnt signaling that is frequently downregulated by hypermethylation of the WIF-1 promoter in acute promyelocytic leukemia (APL) and other malignancies. On the other hand, an acquired mutation in JAK2 tyrosine kinase involving a V617F amino-acid substitution shows a strong association with the pathogenesis of BCR/ABL-negative MPD. This is the first study to examine the relationship between WIF-1 methylation and the existence of JAK2V617F mutation in the pathogenesis of BCR/ABL-negative myeloproliferative disorders (MPD) including polycythemia vera, essential thrombocythemia, idiopathic myelofibrosis, and chronic myeloproliferative disease, unclassifiable. METHODS: We evaluated 49 newly diagnosed and previously treated patients with MPD in chronic phase. Bone marrow (BM) mononuclear cells, when available, or PB mononuclear cells of patients were used for the analysis. The mutation status of JAK2 was analyzed using sequencing analysis. The methylation status of the WIF-1 promoter was analyzed by methylation-specific polymerase chain reaction (MSP). RESULTS: The JAK2V617F mutation was found in 23/49 patients (46.9%) with BCR/ABL-negative MPD, while WIF-1 methylation was detected in 1/49 patients (2.0%). CONCLUSION: WIF-1 is infrequently methylated in BCR/ABL-negative MPD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Janus Quinase 2/genética , Transtornos Mieloproliferativos/enzimologia , Transtornos Mieloproliferativos/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Doença Crônica , Estudos de Coortes , Ilhas de CpG/genética , Feminino , Proteínas de Fusão bcr-abl , Humanos , Masculino , Metilação , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Transtornos Mieloproliferativos/genética , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
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