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1.
J Cachexia Sarcopenia Muscle ; 15(1): 159-172, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-37937369

RÉSUMÉ

BACKGROUND: Spinal and bulbar muscular atrophy (SBMA) is a hereditary neuromuscular disorder caused by the expansion of trinucleotide cytosine-adenine-guanine (CAG) repeats, which encodes a polyglutamine (polyQ) tract in the androgen receptor (AR) gene. Recent evidence suggests that, in addition to motor neuron degeneration, defective skeletal muscles are also the primary contributors to the pathogenesis in SBMA. While benefits of physical exercise have been suggested in SBMA, underlying mechanism remains elusive. METHODS: We investigated the effect of running exercise in a transgenic mouse model of SBMA carrying human AR with 97 expanded CAGs (AR97Q). We assigned AR97Q mice to exercise and sedentary control groups, and mice in the exercise group received 1-h forced running wheel (5 m/min) 5 days a week for 4 weeks during the early stage of the disease. Motor function (grip strength and rotarod performance) and survival of each group were analysed, and histopathological and biological features in skeletal muscles and motor neurons were evaluated. RESULTS: AR97Q mice in the exercise group showed improvement in motor function (~40% and ~50% increase in grip strength and rotarod performance, respectively, P < 0.05) and survival (median survival 23.6 vs. 16.7 weeks, P < 0.05) with amelioration of neuronal and muscular histopathology (~1.4-fold and ~2.8-fold increase in motor neuron and muscle fibre size, respectively, P < 0.001) compared to those in the sedentary group. Nuclear accumulation of polyQ-expanded AR in skeletal muscles and motor neurons was suppressed in the mice with exercise compared to the sedentary mice (~50% and ~30% reduction in 1C2-positive cells in skeletal muscles and motor neurons, respectively, P < 0.05). We found that the exercise activated 5'-adenosine monophosphate-activated protein kinase (AMPK) signalling and inhibited mammalian target of rapamycin pathway that regulates protein synthesis in skeletal muscles of SBMA mice. Pharmacological activation of AMPK inhibited protein synthesis and reduced polyQ-expanded AR proteins in C2C12 muscle cells. CONCLUSIONS: Our findings suggest the therapeutic potential of exercise-induced effect via AMPK activation in SBMA.


Sujet(s)
Amyotrophie bulbospinale liée à l'X , Peptides , Humains , Souris , Animaux , Amyotrophie bulbospinale liée à l'X/génétique , Amyotrophie bulbospinale liée à l'X/métabolisme , Amyotrophie bulbospinale liée à l'X/anatomopathologie , AMP-Activated Protein Kinases , Souris transgéniques , Motoneurones/métabolisme , Mammifères
2.
Front Neurol ; 13: 905613, 2022.
Article de Anglais | MEDLINE | ID: mdl-35812096

RÉSUMÉ

Spinal and bulbar muscular atrophy (SBMA), also known as Kennedy's disease, is a rare, slowly progressive, incurable, and hereditary neurodegenerative disease caused by the testosterone-dependent accumulation of pathogenic polyglutamine-expanded androgen receptor protein. After extensive review, two treatments for SBMA have recently been approved in Japan; this decision was based on the results of randomized controlled trials: First, anti-androgen therapy using leuprorelin acetate (leuprorelin), a disease-modifying drug that can inhibit the progression of dysphagia but has not yet been proved to improve gait function; second, cybernic treatment with a wearable cyborg hybrid assistive limb (HAL®) (Cyberdyne Inc. Tsukuba, Japan). The HAL is an innovative walking exercise system that has been shown to significantly improve gait function in eight neuromuscular diseases without reduction in muscle function, including SBMA. It is possible that the combination of these two approaches might yield better outcomes. However, the long-term effects of such a combined approach have yet to be clinically evaluated. Here, we describe the case of a 39-year-old male with SBMA who commenced anti-androgen therapy with leuprorelin 1 year previously; this was followed by cybernic treatment with HAL. The duration of walking exercise with HAL was 20-30 min a day in one session. Over 2 weeks, the patient underwent nine sessions (one course). The efficacy of HAL was evaluated by gait function tests before and after one course of cybernic treatment. Then, leuprorelin treatment was combined with cybernic sessions every 2 months for 2 years (13 courses in total). Walking ability, as evaluated by the 2-min walk test, improved by 20.3% in the first course and peaked 10 months after the commencement of combined therapy (a 59.0% improvement). Walking function was maintained throughout the period. Generally, SBMA is characterized by moderately increased serum levels of creatine kinase (CK), reflecting neuromuscular damage; interestingly, the patient's CK levels decreased dramatically with combined therapy, indicating remarkable functional improvement. Long-term combined therapy improved the patient's gait function with a steady reduction in CK levels. The combination of leuprorelin with cybernic treatment can, therefore, improve and maintain gait function without damaging the motor unit and may also suppress disease progression.

3.
Nat Commun ; 10(1): 4262, 2019 09 19.
Article de Anglais | MEDLINE | ID: mdl-31537808

RÉSUMÉ

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular disease caused by an expanded CAG repeat in the androgen receptor (AR) gene. Here, we perform a comprehensive analysis of signaling pathways in a mouse model of SBMA (AR-97Q mice) utilizing a phosphoprotein assay. We measure the levels of 17 phosphorylated proteins in spinal cord and skeletal muscle of AR-97Q mice at three stages. The level of phosphorylated Src (p-Src) is markedly increased in the spinal cords and skeletal muscles of AR-97Q mice prior to the onset. Intraperitoneal administration of a Src kinase inhibitor improves the behavioral and histopathological phenotypes of the transgenic mice. We identify p130Cas as an effector molecule of Src and show that the phosphorylated p130Cas is elevated in murine and cellular models of SBMA. These results suggest that Src kinase inhibition is a potential therapy for SBMA.


Sujet(s)
Amyotrophie bulbospinale liée à l'X/anatomopathologie , Muscles squelettiques/métabolisme , Protéines proto-oncogènes pp60(c-src)/métabolisme , Récepteurs aux androgènes/génétique , Moelle spinale/métabolisme , src-Family kinases/antagonistes et inhibiteurs , Animaux , Amyotrophie bulbospinale liée à l'X/génétique , Amyotrophie bulbospinale liée à l'X/thérapie , Lignée cellulaire , Protéine BCAR1/métabolisme , Modèles animaux de maladie humaine , Humains , Mâle , Souris , Souris de lignée C57BL , Souris transgéniques , Phosphorylation , Protéines proto-oncogènes pp60(c-src)/génétique , Interférence par ARN , Petit ARN interférent/génétique
4.
EMBO Mol Med ; 11(5)2019 05.
Article de Anglais | MEDLINE | ID: mdl-30940675

RÉSUMÉ

Spinal and bulbar muscular atrophy (SBMA) is a polyglutamine-mediated neuromuscular disease caused by a CAG repeat expansion in the androgen receptor (AR) gene. While transcriptional dysregulation is known to play a critical role in the pathogenesis of SBMA, the underlying molecular pathomechanisms remain unclear. DNA methylation is a fundamental epigenetic modification that silences the transcription of various genes that have a CpG-rich promoter. Here, we showed that DNA methyltransferase 1 (Dnmt1) is highly expressed in the spinal motor neurons of an SBMA mouse model and in patients with SBMA. Both genetic Dnmt1 depletion and treatment with RG108, a DNA methylation inhibitor, ameliorated the viability of SBMA model cells. Furthermore, a continuous intracerebroventricular injection of RG108 mitigated the phenotype of SBMA mice. DNA methylation array analysis identified hairy and enhancer of split 5 (Hes5) as having a CpG island with hyper-methylation in the promoter region, and the Hes5 expression was strongly silenced in SBMA. Moreover, Hes5 over-expression rescued the SBMA cells possibly by inducing Smad2 phosphorylation. Our findings suggest DNA hyper-methylation underlies the neurodegeneration in SBMA.


Sujet(s)
Facteurs de transcription à motif basique hélice-boucle-hélice/métabolisme , Méthylation de l'ADN , Dégénérescence nerveuse/métabolisme , Dégénérescence nerveuse/anatomopathologie , Peptides/toxicité , Phtalimides/pharmacologie , Protéines de répression/métabolisme , Tryptophane/analogues et dérivés , Sujet âgé , Animaux , Survie cellulaire/effets des médicaments et des substances chimiques , DNA (Cytosine-5-)-methyltransferase 1/métabolisme , Humains , Souris de lignée C57BL , Adulte d'âge moyen , Modèles biologiques , Activité motrice/effets des médicaments et des substances chimiques , Motoneurones/effets des médicaments et des substances chimiques , Motoneurones/enzymologie , Motoneurones/anatomopathologie , Amyotrophie spinale/anatomopathologie , Dégénérescence nerveuse/physiopathologie , Régions promotrices (génétique)/génétique , Récepteurs aux androgènes/métabolisme , Protéine Smad2/métabolisme , Moelle spinale/anatomopathologie , Tryptophane/pharmacologie
5.
J Neurol ; 264(5): 839-847, 2017 May.
Article de Anglais | MEDLINE | ID: mdl-28229243

RÉSUMÉ

This study aimed to evaluate various metabolic parameters in patients with spinal and bulbar muscular atrophy (SBMA), to investigate the association between those indices and disease severity, and to explore the underlying molecular pathogenesis. We compared the degree of obesity, metabolic parameters, and blood pressure in 55 genetically confirmed SBMA patients against those in 483 age- and sex-matched healthy control. In SBMA patients, we investigated the correlation between these factors and motor functional indices. SBMA patients had lower body mass index, blood glucose, and Hemoglobin A1c, but higher blood pressure, homeostasis model assessment of insulin resistance (HOMA-IR, a marker of insulin resistance), total cholesterol, and adiponectin levels than the control subjects. There were no differences in visceral fat areas, high-density lipoprotein-cholesterol (HDL-C), or triglyceride levels in two groups. Revised amyotrophic lateral sclerosis functional rating scale (ALSFRS-R) correlated positively with HDL-C, but negatively with HOMA-IR. Through stepwise multiple regression analysis, we identified HOMA-IR as a significant metabolic determinant of ALSFRS-R. In biochemical analysis, we found that decreased expressions of insulin receptors, insulin receptor substrate-1 and insulin receptor-ß, in autopsied muscles and fibroblasts of SBMA patients. This study demonstrates that SBMA patients have insulin resistance, which is associated with the disease severity. The expressions of insulin receptors are attenuated in the skeletal muscle of SBMA, providing a possible pathomechanism of metabolic alterations. These findings suggested that insulin resistance is a metabolic index reflecting disease severity and pathogenesis as well as a potential therapeutic target for SBMA.


Sujet(s)
Insulinorésistance/physiologie , Maladies métaboliques/étiologie , Activité motrice/physiologie , Troubles de la motricité/étiologie , Amyotrophies/complications , Amyotrophies/métabolisme , Adulte , Glycémie , Indice de masse corporelle , Études cas-témoins , Femelle , Hémoglobine glyquée/métabolisme , Humains , Lipoprotéines HDL/sang , Mâle , Adulte d'âge moyen , Muscles squelettiques/métabolisme , Amyotrophies/génétique , Amyotrophies/anatomopathologie , Récepteur à l'insuline/métabolisme , Indice de gravité de la maladie , Statistiques comme sujet , Triglycéride/sang
6.
Neuroscience ; 327: 20-31, 2016 07 07.
Article de Anglais | MEDLINE | ID: mdl-27058144

RÉSUMÉ

Spinocerebellar ataxia type 1 (SCA1) is a dominantly inherited neurodegenerative disease caused by the expansion of a polyglutamine (polyQ) tract in ataxin-1 (ATXN1). The pathological hallmarks of SCA1 are the loss of cerebellar Purkinje cells and neurons in the brainstem and the presence of nuclear aggregates containing the polyQ-expanded ATXN1 protein. Heat shock protein 90 (Hsp90) inhibitors have been shown to reduce polyQ-induced toxicity. This study was designed to examine the therapeutic effects of BIIB021, a purine-scaffold Hsp90 inhibitor, on the protein homeostasis of polyQ-expanded mutant ATXN1 in a cell culture model of SCA1. Our results demonstrated that BIIB021 activated heat shock factor 1 (HSF1) and suppressed the abnormal accumulation of ATXN1 and its toxicity. The pharmacological degradation of mutant ATXN1 via activated HSF1 was dependent on both the proteasome and autophagy systems. These findings indicate that HSF1 is a key molecule in the regulation of the protein homeostasis of the polyQ-expanded mutant ATXN1 and that Hsp90 has potential as a novel therapeutic target in patients with SCA1.


Sujet(s)
Adénine/analogues et dérivés , Ataxine-1/métabolisme , Tronc cérébral/métabolisme , Cervelet/métabolisme , Protéines de liaison à l'ADN/métabolisme , Protéines du choc thermique HSP90/métabolisme , Pyridines/pharmacologie , Facteurs de transcription/métabolisme , Adénine/pharmacologie , Ataxine-1/génétique , Tronc cérébral/effets des médicaments et des substances chimiques , Cervelet/effets des médicaments et des substances chimiques , Facteurs de transcription de choc thermique , Homéostasie/physiologie , Température élevée , Humains , Protéines de tissu nerveux/métabolisme , Cellules de Purkinje/anatomopathologie , Ataxies spinocérébelleuses/anatomopathologie
7.
Biochem Biophys Res Commun ; 468(4): 677-83, 2015 Dec 25.
Article de Anglais | MEDLINE | ID: mdl-26551462

RÉSUMÉ

Spinal and bulbar muscular atrophy (SBMA) is an inherited motor neuron disease caused by the expansion of a polyglutamine (polyQ)-encoding tract within the androgen receptor (AR) gene. The pathologic features of SBMA are motor neuron loss in the spinal cord and brainstem and diffuse nuclear accumulation and nuclear inclusions of mutant AR in residual motor neurons and certain visceral organs. Hepatocyte growth factor (HGF) is a polypeptide growth factor which has neuroprotective properties. To investigate whether HGF overexpression can affect disease progression in a mouse model of SBMA, we crossed SBMA transgenic model mice expressing an AR gene with an expanded CAG repeat with mice overexpressing HGF. Here, we report that high expression of HGF induces Akt phosphorylation and modestly ameliorated motor symptoms in an SBMA transgenic mouse model treated with or without castration. These findings suggest that HGF overexpression can provide a potential therapeutic avenue as a combination therapy with disease-modifying therapies in SBMA.


Sujet(s)
Castration/méthodes , Modèles animaux de maladie humaine , Facteur de croissance des hépatocytes/métabolisme , Amyotrophies/métabolisme , Amyotrophies/thérapie , Animaux , Association thérapeutique/méthodes , Mâle , Souris , Souris de lignée C57BL , Souris transgéniques , Résultat thérapeutique , Régulation positive
8.
Hum Mol Genet ; 24(21): 5985-94, 2015 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-26231218

RÉSUMÉ

Spinal and bulbar muscular atrophy (SBMA), an adult-onset neurodegenerative disease that affects males, results from a CAG triplet repeat/polyglutamine expansions in the androgen receptor (AR) gene. Patients develop progressive muscular weakness and atrophy, and no effective therapy is currently available. The tissue-specific pathogenesis, especially relative pathological contributions between degenerative motor neurons and muscles, remains inconclusive. Though peripheral pathology in skeletal muscle caused by toxic AR protein has been recently reported to play a pivotal role in the pathogenesis of SBMA using mouse models, the role of motor neuron degeneration in SBMA has not been rigorously investigated. Here, we exploited synthetic antisense oligonucleotides to inhibit the RNA levels of mutant AR in the central nervous system (CNS) and explore its therapeutic effects in our SBMA mouse model that harbors a mutant AR gene with 97 CAG expansions and characteristic SBMA-like neurogenic phenotypes. A single intracerebroventricular administration of the antisense oligonucleotides in the presymptomatic phase efficiently suppressed the mutant gene expression in the CNS, and delayed the onset and progression of motor dysfunction, improved body weight gain and survival with the amelioration of neuronal histopathology in motor units such as spinal motor neurons, neuromuscular junctions and skeletal muscle. These findings highlight the importance of the neurotoxicity of mutant AR protein in motor neurons as a therapeutic target.


Sujet(s)
Amyotrophie spinale/génétique , Récepteurs aux androgènes/génétique , Animaux , Évolution de la maladie , Expression des gènes/effets des médicaments et des substances chimiques , Extinction de l'expression des gènes , Souris , Souris transgéniques , Motoneurones , Muscles squelettiques/anatomopathologie , Amyotrophie spinale/anatomopathologie , Amyotrophie spinale/thérapie , Mutation , Jonction neuromusculaire/anatomopathologie , Oligonucléotides antisens/administration et posologie
9.
Proc Natl Acad Sci U S A ; 112(16): E2058-66, 2015 Apr 21.
Article de Anglais | MEDLINE | ID: mdl-25848057

RÉSUMÉ

Chronic low-grade inflammation of adipose tissue plays a crucial role in the pathophysiology of obesity. Immunohistological microscopic analysis in obese fat tissue has demonstrated the infiltration of several immune cells such as macrophages, but dynamics of immune cells have not been fully elucidated and clarified. Here, by using intravital multiphoton imaging technique, to our knowledge for the first time, we analyzed and visualized the inflammatory processes in adipose tissue under high-fat and high-sucrose (HF/HS) diet with lysozyme M-EGFP transgenic (LysM(EGFP)) mice whose EGFP was specifically expressed in the myelomonocytic lineage. Mobility of LysM(EGFP)-positive macrophages was shown to be activated just 5 d after HF/HS diet, when the distinct hypertrophy of adipocytes and the accumulation of macrophages still have not become prominent. Significant increase of S100A8 was detected in mature adipocyte fraction just 5 d after HF/HS diet. Recombinant S100A8 protein stimulated chemotactic migration in vitro and in vivo, as well as induced proinflammatory molecules, both macrophages and adipocytes, such as TNF-α and chemokine (C-C motif) ligand 2. Finally, an antibody against S100A8 efficiently suppressed the HF/HS diet-induced initial inflammatory change, i.e., increased mobilization of adipose LysM(EGFP)-positive macrophages, and ameliorated HF/HS diet-induced insulin resistance. In conclusion, time-lapse intravital multiphoton imaging of adipose tissues identified the very early event exhibiting increased mobility of macrophages, which may be triggered by increased expression of adipose S100A8 and results in progression of chronic inflammation in situ.


Sujet(s)
Adiposité , Calgranuline A/métabolisme , Macrophages/anatomopathologie , Obésité/métabolisme , Obésité/anatomopathologie , Cellules 3T3-L1 , Adipocytes/effets des médicaments et des substances chimiques , Adipocytes/métabolisme , Adipocytes/anatomopathologie , Adiposité/effets des médicaments et des substances chimiques , Animaux , Anticorps/pharmacologie , Calgranuline A/génétique , Chimiotaxie/effets des médicaments et des substances chimiques , Alimentation riche en graisse , Épididyme/effets des médicaments et des substances chimiques , Épididyme/anatomopathologie , Protéines à fluorescence verte/métabolisme , Inflammation/anatomopathologie , Insuline/pharmacologie , Lipopolysaccharides/pharmacologie , Macrophages/effets des médicaments et des substances chimiques , Macrophages/métabolisme , Mâle , Souris , Microscopie de fluorescence multiphotonique , Lysozyme/métabolisme , Obésité/sang , ARN messager/génétique , ARN messager/métabolisme , Régulation positive/effets des médicaments et des substances chimiques
10.
Hum Mol Genet ; 24(2): 314-29, 2015 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-25168383

RÉSUMÉ

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular disease caused by the expansion of a CAG repeat in the androgen receptor (AR) gene. Mutant AR has been postulated to alter the expression of genes important for mitochondrial function and induce mitochondrial dysfunction. Here, we show that the expression levels of peroxisome proliferator-activated receptor-γ (PPARγ), a key regulator of mitochondrial biogenesis, were decreased in mouse and cellular models of SBMA. Treatment with pioglitazone (PG), an activator of PPARγ, improved the viability of the cellular model of SBMA. The oral administration of PG also improved the behavioral and histopathological phenotypes of the transgenic mice. Furthermore, immunohistochemical and biochemical analyses demonstrated that the administration of PG suppressed oxidative stress, nuclear factor-κB (NFκB) signal activation and inflammation both in the spinal cords and skeletal muscles of the SBMA mice. These findings suggest that PG is a promising candidate for the treatment of SBMA.


Sujet(s)
Muscles squelettiques/effets des médicaments et des substances chimiques , Amyotrophies/traitement médicamenteux , Neurones/effets des médicaments et des substances chimiques , Peptides/métabolisme , Récepteurs aux androgènes/génétique , Thiazolidinediones/administration et posologie , Animaux , Modèles animaux de maladie humaine , Humains , Mâle , Souris , Souris de lignée C57BL , Souris transgéniques , Muscles squelettiques/métabolisme , Amyotrophies/génétique , Amyotrophies/métabolisme , Neurones/métabolisme , Récepteurs activés par les proliférateurs de peroxysomes/génétique , Récepteurs activés par les proliférateurs de peroxysomes/métabolisme , Pioglitazone , Récepteurs aux androgènes/métabolisme , Moelle spinale/effets des médicaments et des substances chimiques , Moelle spinale/métabolisme , Expansion de trinucléotide répété/effets des médicaments et des substances chimiques
11.
FEBS Open Bio ; 4: 276-82, 2014.
Article de Anglais | MEDLINE | ID: mdl-24918039

RÉSUMÉ

Adiponectin is exclusively synthesized by adipocytes and exhibits anti-diabetic, anti-atherosclerotic and anti-inflammatory properties. Hypoadiponectinemia is associated in obese individuals with insulin resistance and atherosclerosis. However, the mechanisms responsible for hypoadiponectinemia remain unclear. Here, we investigated adiponectin movement using hetero parabiosis model of wild type (WT) and adiponectin-deficient (KO) mice. WT mice were parabiosed with WT mice (WT-WT) or KO mice (WT-KO) and adiponectin levels were measured serially up to 63 days after surgery. In the WT-KO parabiosis model, circulating adiponectin levels of the WT partners decreased rapidly, on the other hand, those of KO partners increased, and then these reached comparable levels each other at day 7. Circulating adiponectin levels decreased further to the detection limit of assay, and remained low up to day 63. However, adiponectin protein was detected in the adipose tissues of not only the WT partner but also WT-KO mice. In the diet-induced obesity model, high adiponectin protein levels were detected in adipose stromal vascular fraction of diet-induced obese KO partner, without changes in its binding proteins. The use of parabiosis experiments shed light on movement of native adiponectin among different tissues such as the state of hypoadiponectinemia in obesity.

12.
Neurology ; 82(20): 1813-21, 2014 May 20.
Article de Anglais | MEDLINE | ID: mdl-24759840

RÉSUMÉ

OBJECTIVE: The aim of this study was to clarify myocardial involvement and its clinical implications in subjects with spinal and bulbar muscular atrophy (SBMA), a neuromuscular disease affecting both neuronal and nonneuronal tissues. METHODS: Two independent cardiologists evaluated ECGs from a total of 144 consecutive subjects with SBMA. We performed immunohistochemical, immunoblot, and quantitative real-time PCR analyses of autopsied myocardium. RESULTS: Abnormal ECGs were detected in 70 (48.6%) of 144 subjects. The most frequent findings were ST-segment abnormalities in V1-3 (19.4%), followed by ST-segment abnormalities in V5-6 (18.1%). We detected Brugada-type ECGs in 17 of 28 subjects with ST-segment abnormalities in V1-3. Of those, one subject presented with syncope that required an implantable cardioverter defibrillator and led to eventual sudden death, and another subject also died suddenly. No subjects with Brugada-type ECGs had mutations in SCN5A, CACNA1C, or CACNB2 genes. In autopsied cases, we detected nuclear accumulation of the mutant androgen receptor protein and decreased expression levels of SCN5A in the myocardium. CONCLUSIONS: Subjects with SBMA often show Brugada-type ECG. The accumulation of the pathogenic androgen receptor may have a role in the myocardial involvement in SBMA.


Sujet(s)
Syndrome de Brugada/complications , Amyotrophies/complications , Adulte , Sujet âgé , Syndrome de Brugada/génétique , Syndrome de Brugada/anatomopathologie , Électrocardiographie , Femelle , Humains , Mâle , Adulte d'âge moyen , Amyotrophies/génétique , Amyotrophies/anatomopathologie , Mutation , Myocarde/métabolisme , Myocarde/anatomopathologie , Récepteurs aux androgènes/génétique
13.
Hum Mol Genet ; 23(13): 3552-65, 2014 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-24549037

RÉSUMÉ

The accumulation of abnormal proteins is a common characteristic of neurodegenerative diseases. This accumulation reflects a severe disturbance of cellular homeostasis in pathogenic protein clearance. Here, we demonstrated that the activation of the two major proteolytic machineries, the molecular chaperone-ubiquitin proteasome system (UPS) and the autophagy system, were simultaneously enhanced by paeoniflorin (PF), a major component of Paeonia plants, and exerted therapeutic effects in models of spinal and bulbar muscular atrophy (SBMA). PF significantly increased the expression of nuclear factor-YA (NF-YA), which strongly upregulated the molecules involved in the proteolytic machinery [molecular chaperones, carboxyl terminus of Hsc70-interacting protein and transcription factor EB], which thus mitigated the behavioral and pathological impairments in an SBMA mouse model through the upregulation of pathogenic androgen receptor protein clearance in motor neurons and muscles. These findings demonstrated that PF is able to enhance both the UPS and autophagy systems by upregulating the expression of NF-YA, which promotes therapeutic effects in an SBMA model.


Sujet(s)
Glucosides/usage thérapeutique , Monoterpènes/usage thérapeutique , Récepteurs aux androgènes/génétique , Animaux , Lignée cellulaire , Survie cellulaire/génétique , Survie cellulaire/physiologie , Survie cellulaire/effets des radiations , Immunohistochimie , Souris , Amyotrophie spinale , Protéolyse/effets des médicaments et des substances chimiques , Réaction de polymérisation en chaine en temps réel
14.
Metabolism ; 63(4): 542-53, 2014 Apr.
Article de Anglais | MEDLINE | ID: mdl-24467915

RÉSUMÉ

OBJECTIVE: Adipose tissue inflammation plays an important role in the pathogenesis of obesity-associated complications, such as atherosclerosis. Adiponectin secreted from adipocytes has various beneficial effects including anti-inflammatory effect. Obesity often presents with hypoadiponectinemia. However, the mechanism and adiponectin movement in obesity remain uncharacterized. Here we investigated tissue distribution of adiponectin protein in lean and obese mice. METHODS: Adiponectin protein levels were evaluated by enzyme-linked immunosorbent assay and western blotting. Adipose tissues were fractionated into mature adipocyte fraction (MAF) and stromal vascular fraction (SVF). RESULTS: Adiponectin protein was detected not only in MAF but also in SVF, which lacks adiponectin mRNA expression, of adipose tissue remarkably. SVF adiponectin protein level was higher in obese mice than in lean mice. The mechanism of adiponectin accumulation was investigated in adiponectin-deficient (APN-KO) mice after injection of plasma from wild-type mice. These mice showed accumulation of exogenous adiponectin, which derived from wild type mice, in adipose tissues, and the adiponectin was more observed in SVF of diet induced obese APN-KO mice than lean APN-KO mice. Among the adiponectin binding proteins, T-cadherin mRNA and protein levels in SVF of obese mice were remarkably higher than in lean mice. Oxidative stress levels were also significantly higher in SVF of obese mice than lean mice. Mechanistically, H2O2 up-regulated T-cadherin mRNA level in murine macrophages. CONCLUSIONS: The results demonstrated adiponectin targets to adipose SVF of obese mice. These findings should shed a new light on the pathology of adipose tissue inflammation and hypoadiponectinemia of obesity.


Sujet(s)
Adiponectine/métabolisme , Tissu adipeux/métabolisme , Inflammation/métabolisme , Obésité/métabolisme , Adiponectine/génétique , Tissu adipeux/anatomopathologie , Animaux , Séquence nucléotidique , Technique de Western , Cadhérines/génétique , Lignée cellulaire , Amorces ADN , Test ELISA , Inflammation/anatomopathologie , Mâle , Souris , Souris knockout , Obésité/anatomopathologie , ARN messager/génétique , Espèces réactives de l'oxygène/métabolisme , Réaction de polymérisation en chaine en temps réel
15.
PLoS One ; 8(8): e71271, 2013.
Article de Anglais | MEDLINE | ID: mdl-23967179

RÉSUMÉ

AIMS: Inflammation is closely associated with the development of atherosclerosis and metabolic syndrome. Adiponectin, an adipose-derived secretory protein, possesses an anti-atherosclerotic property. The present study was undertaken to elucidate the presence and significance of adiponectin in vasculature. METHODS AND RESULTS: Immunofluorescence staining was performed in aorta of wild-type (WT) mice and demonstrated that adiponectin was co-stained with CD31. Thoracic aorta was cut through and then aortic intima was carefully shaved from aorta. Western blotting showed the existence of adiponectin protein in aortic intima, while there was no adiponectin mRNA expression. Adiponectin knockout (Adipo-KO) and WT mice were administered with a low-dose and short-term lipopolysaccharide (LPS) (1 mg/kg of LPS for 4 hours). The endothelium vascular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were highly increased in Adipo-KO mice compared to WT mice after LPS administration. CONCLUSIONS: Adiponectin protein exists in aortic endothelium under steady state and may protect vasculature from the initiation of atherosclerosis.


Sujet(s)
Adiponectine/métabolisme , Aorte/métabolisme , Cellules endothéliales/métabolisme , Endothélium vasculaire/métabolisme , Adiponectine/déficit , Adiponectine/génétique , Animaux , Molécules d'adhérence cellulaire/génétique , Molécules d'adhérence cellulaire/métabolisme , Immunohistochimie , Lipopolysaccharides , Souris , Souris knockout , Tunique intime/métabolisme
16.
J Biol Chem ; 288(38): 27138-27149, 2013 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-23913681

RÉSUMÉ

Obesity is often accompanied by hyperuricemia. However, purine metabolism in various tissues, especially regarding uric acid production, has not been fully elucidated. Here we report, using mouse models, that adipose tissue could produce and secrete uric acid through xanthine oxidoreductase (XOR) and that the production was enhanced in obesity. Plasma uric acid was elevated in obese mice and attenuated by administration of the XOR inhibitor febuxostat. Adipose tissue was one of major organs that had abundant expression and activities of XOR, and adipose tissues in obese mice had higher XOR activities than those in control mice. 3T3-L1 and mouse primary mature adipocytes produced and secreted uric acid into culture medium. The secretion was inhibited by febuxostat in a dose-dependent manner or by gene knockdown of XOR. Surgical ischemia in adipose tissue increased local uric acid production and secretion via XOR, with a subsequent increase in circulating uric acid levels. Uric acid secretion from whole adipose tissue was increased in obese mice, and uric acid secretion from 3T3-L1 adipocytes was increased under hypoxia. Our results suggest that purine catabolism in adipose tissue could be enhanced in obesity.


Sujet(s)
Adipocytes/métabolisme , Tissu adipeux/métabolisme , Obésité/métabolisme , Acide urique/métabolisme , Xanthine dehydrogenase/métabolisme , Cellules 3T3-L1 , Adipocytes/anatomopathologie , Tissu adipeux/anatomopathologie , Animaux , Hypoxie cellulaire , Techniques de knock-down de gènes , Mâle , Souris , Souris obèse , Obésité/génétique , Obésité/anatomopathologie , Xanthine dehydrogenase/génétique
17.
Diabetol Metab Syndr ; 5(1): 17, 2013 Mar 27.
Article de Anglais | MEDLINE | ID: mdl-23531423

RÉSUMÉ

BACKGROUND: Atherosclerosis is an age-related disease. Adiponectin and C1q form a protein complex in human blood, and that serum C1q and C1q-binding adiponectin (C1q-APN) concentrations can be measured. We investigated circulating C1q and C1q-APN levels in Japanese men including elderly men. FINDINGS: The study subjects were 509 Japanese men including elderly men. Serum levels of total adiponectin (Total-APN), high-molecular weight-adiponectin (HMW-APN), C1q-APN and C1q were measured by enzyme-linked immunosorbent assay. Total-APN, HMW-APN and C1q-APN, but not C1q, correlated significantly and positively with aging (r=0.26, r=0.24, r=0.17, p<0.01, respectively). The HMW-APN/Total-APN ratio correlated significantly and positively with aging (r=0.14, p<0.01). The C1q-APN/Total-APN ratio and C1q-APN/HMW-APN ratio correlated significantly and negatively with aging (r=-0.17, p<0.01, r=-0.12, p=0.01). C1q-APN/C1q correlated significantly and positively with aging (r=0.09, p=0.03). Multiple regression analysis identified age and body mass index as significant determinants of C1q-APN. CONCLUSIONS: The present study demonstrates that serum HMW-APN, C1q-APN, and Total-APN, but not C1q, correlated positively with aging. These preliminary results could form the basis for future research. CLINICAL TRIAL REGISTRATION NUMBER: UMIN000004318.

18.
BMC Nephrol ; 14: 50, 2013 Feb 26.
Article de Anglais | MEDLINE | ID: mdl-23442371

RÉSUMÉ

BACKGROUND: Patients on maintenance hemodialysis (HD) have much higher levels of adiponectin (Total-APN). Adiponectin and C1q form a protein complex in human blood, and serum C1q-binding adiponectin (C1q-APN) can be measured. We recently reported that C1q-APN/Total-APN ratio rather than Total-APN correlated with atherosclerosis in diabetics. However, the characteristics of C1q-APN in HD patients remain unclear. The preset study investigated the characteristics of the adiponectin parameters including C1q-APN and also to clarify the relationship between various serum adiponectin parameters and atherosclerotic cardiovascular diseases (ACVD) in HD patients. METHODS: The single cross-sectional study subjects were 117 Japanese patients (males/females = 61/56) on regular HD. Blood Total-APN, high molecular weight-adiponectin (HMW-APN), C1q-APN and C1q concentrations were measured by enzyme-linked immunosorbent assays. ACVD were defined as stroke, coronary and peripheral artery diseases, thoracic and abdominal aneurysms. RESULTS: Stepwise regression analysis identified high-density lipoprotein-cholesterol (HDL-C) as the only significant and independent determinant of C1q-APN in males, and duration of HD as the only significant and independent determinant of C1q-APN in females. Stepwise regression analysis identified uric acid, low-density lipoprotein-cholesterol and triglyceride as significant and independent determinants of C1q-APN/Total-APN ratio in males, and leukocyte count and HDL-C as significant and independent determinants of C1q-APN/Total-APN ratio in females. Multiple logistic regression analysis identified inorganic phosphorus and C1q-APN or C1q-APN/C1q ratio as significant determinants of ACVD. CONCLUSIONS: Low serum C1q-APN and C1q-APN/C1q ratio, but not C1q-APN/Total-APN ratio, correlated with ACVD in HD patients. TRIAL REGISTRATION: ClinicalTrials.gov: UMIN http://000004318.


Sujet(s)
Adiponectine/sang , Complément C1q/métabolisme , Maladie des artères coronaires/sang , Maladie des artères coronaires/épidémiologie , Dialyse rénale/statistiques et données numériques , Insuffisance rénale chronique/sang , Insuffisance rénale chronique/rééducation et réadaptation , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Comorbidité , Femelle , Humains , Japon/épidémiologie , Mâle , Adulte d'âge moyen , Insuffisance rénale chronique/épidémiologie , Résultat thérapeutique
19.
Nat Commun ; 4: 1405, 2013.
Article de Anglais | MEDLINE | ID: mdl-23360996

RÉSUMÉ

A crucial feature of adult-onset neurodegenerative diseases is accumulation of abnormal protein in specific brain regions, although the mechanism underlying this pathological selectivity remains unclear. Heat shock factor-1 is a transcriptional regulator of heat shock proteins, molecular chaperones that abrogate neurodegeneration by refolding and solubilizing pathogenic proteins. Here we show that heat shock factor-1 expression levels are associated with the accumulation of pathogenic androgen receptor in spinal and bulbar muscular atrophy, a polyglutamine-induced neurodegenerative disease. In heterozygous heat shock factor-1-knockout spinal and bulbar muscular atrophy mice, abnormal androgen receptor accumulates in the cerebral visual cortex, liver and pituitary, which are not affected in their genetically unmodified counterparts. The depletion of heat shock factor-1 also expands the distribution of pathogenic androgen receptor accumulation in other neuronal regions. Furthermore, lentiviral-mediated delivery of heat shock factor-1 into the brain of spinal and bulbar muscular atrophy mice topically suppresses the pathogenic androgen receptor accumulation and neuronal atrophy. These results suggest that heat shock factor-1 influences the pathological lesion selectivity in spinal and bulbar muscular atrophy.


Sujet(s)
Protéines de liaison à l'ADN/métabolisme , Dégénérescence nerveuse/métabolisme , Dégénérescence nerveuse/anatomopathologie , Peptides/toxicité , Facteurs de transcription/métabolisme , Sujet âgé , Animaux , Système nerveux central/métabolisme , Système nerveux central/anatomopathologie , Cellules HEK293 , Facteurs de transcription de choc thermique , Protéines du choc thermique/métabolisme , Hétérozygote , Humains , Immunohistochimie , Souris , Souris de lignée C57BL , Souris knockout , Adulte d'âge moyen , Cortex moteur/effets des médicaments et des substances chimiques , Cortex moteur/métabolisme , Cortex moteur/anatomopathologie , Amyotrophies/métabolisme , Amyotrophies/anatomopathologie , Protéines mutantes/métabolisme , Néostriatum/effets des médicaments et des substances chimiques , Néostriatum/métabolisme , Néostriatum/anatomopathologie , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Neurones/anatomopathologie , Spécificité d'organe/effets des médicaments et des substances chimiques , Hypophyse/métabolisme , Récepteurs aux androgènes/métabolisme , Transgènes
20.
Metabolism ; 62(1): 109-20, 2013 Jan.
Article de Anglais | MEDLINE | ID: mdl-22819529

RÉSUMÉ

OBJECTIVE: Adiponectin and C1q have similar sequences, exist abundantly in blood, and are produced by adipose tissues. The aim of this study was to examine whether adiponectin and C1q form protein-complex in blood and to know the clinical significance of the C1q-adiponectin (C1q-APN) complex in serum. METHODS: The direct interaction between adiponectin and C1q was investigated by far western blotting and co-immunoprecipitation. The relationship between serum C1q-APN and various clinical features was analyzed in 329 Japanese men who underwent health check-up, including measurements of visceral (VFA) and subcutaneous fat area (SFA) by computed tomography (Victor-J study). RESULTS: Adiponectin bound to C1q in vitro and C1q-APN complex existed in human blood. C1q-APN complexes were identified in high- and middle-molecular weight forms of adiponectin in human serum by gel-filtration chromatography. Stepwise multiple regression analysis identified body mass index, VFA and SFA as significant determinants of serum C1q-APN level. Serum C1q-APN/Total-APN ratio correlated positively with cardiovascular risk factor accumulation in subjects with VFA ≥100 cm(2). CONCLUSIONS: These results indicate that high- and middle-molecular forms of adiponectin partly consist of adiponectin-complex with other proteins including C1q and that the blood C1q-APN/Total-APN ratio may serve as a biomarker of the metabolic syndrome in general male subjects.


Sujet(s)
Adiponectine/sang , Complément C1q/métabolisme , Syndrome métabolique X/sang , Adulte , Sujet âgé , Alanine transaminase/sang , Aspartate aminotransferases/sang , Marqueurs biologiques/sang , Technique de Western , Humains , Immunoprécipitation , Graisse intra-abdominale/métabolisme , Mâle , Syndrome métabolique X/métabolisme , Adulte d'âge moyen , Courbe ROC , Graisse sous-cutanée/métabolisme , Triglycéride/sang
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