Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Neurosci ; 18: 1378619, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655109

RESUMO

Responses to a sensory stimulus are inhibited by a preceding stimulus; if the two stimuli are identical, paired-pulse suppression (PPS) occurs; if the preceding stimulus is too weak to reliably elicit the target response, prepulse inhibition (PPI) occurs. PPS and PPI represent excitability changes in neural circuits induced by the first stimulus, but involve different mechanisms and are impaired in different diseases, e.g., impaired PPS in schizophrenia and Alzheimer's disease and impaired PPI in schizophrenia and movement disorders. Therefore, these measures provide information on several inhibitory mechanisms that may have roles in clinical conditions. In the present study, PPS and PPI of the auditory change-related cortical response were examined to establish normative data on healthy subjects (35 females and 32 males, aged 19-70 years). We also investigated the effects of age and sex on PPS and PPI to clarify whether these variables need to be considered as biases. The test response was elicited by an abrupt increase in sound pressure in a continuous sound and was recorded by electroencephalography. In the PPS experiment, the two change stimuli to elicit the cortical response were a 15-dB increase from the background of 65 dB separated by 600 ms. In the PPI experiment, the prepulse and test stimuli were 2- and 10-dB increases, respectively, with an interval of 50 ms. The results obtained showed that sex exerted similar effects on the two measures, with females having stronger test responses and weaker inhibition. On the other hand, age exerted different effects: aging correlated with stronger test responses and weaker inhibition in the PPS experiment, but had no effects in the PPI experiment. The present results suggest age and sex biases in addition to normative data on PPS and PPI of auditory change-related potentials. PPS and PPI, as well as other similar paradigms, such as P50 gating, may have different and common mechanisms. Collectively, they may provide insights into the pathophysiologies of diseases with impaired inhibitory function.

2.
Endocr J ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38684424

RESUMO

49,XXXYY is an extremely rare sex chromosomal aneuploidy (SCA), with only seven cases reported worldwide to date. Among these cases, only three have been documented into adulthood. Moreover, no cases of 49,XXXYY have been reported in Japan. This SCA has been identified in two scenarios: in vitro fertilization and abortion. Similar to 47,XXY, this aneuploidy is a type of Klinefelter syndrome. Aneuploidy of the X chromosome can lead to various progressive complications due to excess X chromosomes. Herein, we present the case of a Japanese man with 49,XXXYY. He exhibited developmental delays and external genitalia abnormalities since early infancy but was not closely monitored for these symptoms until the age of 3 years old. At that time, a chromosome test revealed his karyotype to be 49,XXXYY. Subsequent examinations were conducted due to various symptoms, including delayed motor development, intellectual disability, facial dysmorphisms, forearm deformities, hip dysplasia, cryptorchidism, micropenis, primary hypogonadism, and essential tremor. Since reaching puberty, he has undergone testosterone replacement therapy for primary hypogonadism, experiencing no complications related to androgen deficiency to date. He has maintained normal lipid and glucose metabolism, as well as bone density, for a prolonged period. There are no other reports on the long-term effects of testosterone treatment for the SCA. Appropriate testosterone replacement therapy is recommended for individuals with 49,XXXYY to prevent complications. This report will contribute to an enhanced understanding of the 49,XXXYY phenotype, aiding in the diagnosis, treatment, and genetic counseling of future cases.

3.
J Oral Biosci ; 65(1): 111-118, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36640838

RESUMO

OBJECTIVES: Glycocalyx lines the vascular intraluminal space that regulates fluid movement between the intra- and extra-vascular compartments. The depletion of glycocalyx (GCX) is associated with leukocyte accumulation, possibly causing the endothelial cells to become hyperpermeable in various organs, including oral tissues. Whether neutrophils or macrophages are responsible for developing interstitial edema remains controversial. We explored the pathophysiological mechanism of interstitial edema by examining the role of reactive neutrophils and macrophages and their interactions with GCX. METHODS: An anti-MHC class I antibody was administered intravenously to male BALB/c mice to induce pulmonary edema. Pulmonary edema was evaluated by measuring the lung wet-to-dry weight ratio. Changes in the GCX were evaluated by electron microscopy and measurements of the serum level of soluble syndecan-1. Heparin sulfate was administered to examine its protective effect on the GCX. The macrophages were depleted using clodronate to examine their role in developing edema. RESULTS: The GCX degradation induced by the anti-MHC class I antibody was accompanied by increased serum syndecan-1 and heparan sulfate levels. Macrophage depletion inhibited the development of pulmonary edema, and the administration of supplemental heparin suppressed the edema. CONCLUSIONS: We demonstrated that the degradation of the GCX induced by the anti-MHC class I antibody was suppressed by macrophage depletion. These results suggest that macrophages may play a key role in interstitial edema. Heparin inhibited both the degradation of the GCX and interstitial edema. This study's results may be extrapolated to develop an interventional strategy for inhibiting interstitial edema in various organs.


Assuntos
Células Endoteliais , Edema Pulmonar , Camundongos , Animais , Masculino , Células Endoteliais/metabolismo , Sindecana-1/metabolismo , Sindecana-1/farmacologia , Glicocálix/metabolismo , Edema Pulmonar/metabolismo , Heparina/metabolismo , Heparina/farmacologia
4.
Zoolog Sci ; 39(2): 186-192, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35380189

RESUMO

Hybridization induced by human activities, such as crossbreeding between invasive and native species, can adversely affect the natural biodiversity of an ecosystem. In Japan, the endemic turtle species Mauremys japonica is known to hybridize with the alien species Mauremys reevesii, and putative hybrids have been encountered in the wild. If M. japonica × M. reevesii hybrids can readily crossbreed with M. japonica, the hybridization with M. reevesii could lead to the extinction of pure M. japonica populations. However, information on the reproductive ability of M. japonica × M. reevesii hybrids is limited. In this study, we collected wild-caught hybrids from across western Japan to assess their reproductive ability. We investigated the nesting season timing, clutch size, embryonic development, hatching success, and sperm viability. The results showed that female hybrids nested during the same months as the parental species and had similar clutch sizes and hatching success. No embryonic development abnormalities were detected, and viable sperm were observed in all hybrid male semen samples. In conclusion, the fertility of M. japonica × M. reevesii hybrids appears to be similar to the fertilities of the parental species, posing a potential challenge for M. japonica conservation.


Assuntos
Tartarugas , Animais , Ecossistema , Feminino , Espécies Introduzidas , Japão , Masculino , Reprodução , Tartarugas/genética
5.
PLoS One ; 17(4): e0267307, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35436314

RESUMO

Laos, a mountainous and landlocked country located in Southeast Asia, has the highest percentage of people using insects as food in the world. Lao people obtain edible insects through harvesting in the natural environment and purchasing at food markets. There has been no comprehensive survey about sales of insects at food markets in the wider areas, and our understanding of sales of insects in Laos is limited. Our study aims to identify environmental factors affecting the sales and the diversity of edible insects sold at food markets in Laos. We visited 37 and 55 markets, during the dry and rainy seasons respectively, in northern Laos to record species of sold insects. We then analyzed the correlations between insect sales and three potential factors (seasons, provinces, and urbanization indices around the markets). There was no significant difference in the percentage of markets selling insects between in the dry and rainy seasons; 40-50% of the markets sold insects in both seasons. The composition of sold insects differed between in the dry and rainy seasons, which reflects the seasonality and life history of each insect species. There tended to be more groups of insects for sale in the Vientiane capital than in the other provinces in both seasons. This trend may reflect that it is more difficult to obtain edible insects through wild harvesting in highly urbanized Vientiane capital than in the other provinces, and the commercial demand for insects is increasing. This possibility is directly supported by the positive correlation between the urbanization index and the insect sales in the rainy season. Laos has recently undergone rapid urbanization, particularly in the Vientiane capital, and we predict that commercial demand for edible insects will be much higher in the Vientiane capital and the urbanized cities in the future.


Assuntos
Insetos Comestíveis , Animais , Geografia , Humanos , Insetos , Laos , Estações do Ano , Urbanização
6.
Front Immunol ; 12: 677572, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912197

RESUMO

Lipopolysaccharide-responsive beige-like anchor (LRBA) deficiency is a subtype of common variable immune deficiency (CVID). Numerous case reports and cohort studies have described a broad spectrum of clinical manifestations and variable disease phenotypes, including immune dysregulation, enteropathy, and recurrent infections. Although LRBA deficiency is an autosomal recessive primary immunodeficiency resulting in a phenotype similar to CVID, it is a monogenic disease and separate from CVID. Recently, in a report of monogenic primary immunodeficiency disorder associated with CVID and autoimmunity, the most common mutated gene was LRBA. We report the case of a girl who presented with fulminant type 1 diabetes at age 7 months. She later experienced recurrent bacterial infections with neutropenia and idiopathic thrombocytopenic purpura. Clinical genome sequencing revealed compound heterozygosity of the LRBA gene, which bore two novel mutations. A genetic basis should be considered in the differential diagnosis for very young patients with fulminant autoimmunity, and the diagnostic work-up should include evaluation of markers of immunodeficiency.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Imunodeficiência de Variável Comum/diagnóstico , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Deleção de Genes , Heterozigoto , Doenças da Imunodeficiência Primária/diagnóstico , Autoimunidade , Imunodeficiência de Variável Comum/genética , Diabetes Mellitus Tipo 1/imunologia , Diagnóstico Diferencial , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Lactente , Linhagem , Fenótipo , Doenças da Imunodeficiência Primária/genética
7.
eNeurologicalSci ; 20: 100260, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32885055

RESUMO

•The case of infant ischemic stroke with remarkable DWI reversal.•A mismatch between core volume and visually DWI lesion predicts DWI reversal.•Chronic hypoxia and early recanalization may contribute to large DWI reversal.•Mismatch between DWI-ASPECTS and core volume may occur in infant brain.

8.
Heart ; 106(12): 910-915, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32188625

RESUMO

OBJECTIVES: von Willebrand factor (vWF) has prognostic value in patients with heart failure (HF) and in those with liver disease. Liver congestion, due to right-sided HF (RHF), is one of the major clinical pathophysiologic manifestations in adults with congenital heart disease (ACHD). The present study's purpose was to clarify the prognostic value of plasma levels of vWF antigen (vWF:Ag) in ACHD. METHODS: We measured vWF:Ag (%) in 382 consecutive patients (20 unrepaired cyanotic ACHD, 172 Fontan patients and 190 ACHD after biventricular repair) and compared the results with the clinical profiles and prognosis. RESULTS: The plasma vWF:Ag level was 130±53 (normal range: 55%-190%), and 48 patients (13%) showed high levels of vWF:Ag (≥190%). Older age, Fontan circulation, higher central venous pressure, lower arterial oxygen saturation and lower plasma levels of albumin were independently associated with high log (vWF:Ag) (p<0.05-0.0001). During the follow-up of 2.4±1.4 years, 15 patients died. High log (vWF:Ag) predicted the all-cause mortality (HR 1.63 per 0.1, 95% CI 1.40 to 1.96, p<0.0001). Specifically, patients with high vWF:Ag (≥165%) had a substantially higher risk of all-cause mortality (HR 56.4, 95% CI 11.4 to 1020, p<0.0001), and this prognostic value was independent of plasma levels of brain-type natriuretic peptide. CONCLUSIONS: High vWF:Ag may reflect RHF severity and related liver dysfunction with a strong prognostic value of all-cause mortality in ACHD. Thus, vWF:Ag might be an excellent biomarker for monitoring ACHD with RHF.


Assuntos
Cardiopatias Congênitas/complicações , Hepatopatias/diagnóstico , Testes de Função Hepática , Sobreviventes , Fator de von Willebrand/metabolismo , Adulto , Biomarcadores/sangue , Feminino , Técnica de Fontan , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/mortalidade , Cardiopatias Congênitas/cirurgia , Insuficiência Cardíaca/etiologia , Humanos , Hepatopatias/sangue , Hepatopatias/etiologia , Hepatopatias/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Adulto Jovem
9.
Brain Sci ; 9(11)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731567

RESUMO

Carbon monoxide (CO) poisoning causes severe brain damage, including delayed neuropsychiatric sequelae (DNS), which occur after a lucid interval following recovery from the insult of acute CO poisoning. We describe a 39-year-old male who developed DNS, including gait disturbance, trunk ataxia, and fecal/urine incontinence, after remission of acute CO poisoning. Furthermore, he showed confusion, with disorientation in terms of time and space. All symptoms, including cognitive impairment, were dramatically improved by amantadine monotherapy. The present case illustrates the possibility of amantadine treatment for cognitive impairment as well as Parkinsonism induced by CO poisoning.

10.
Am Heart J ; 216: 125-135, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31425899

RESUMO

BACKGROUND: Fontan patients exhibit a high prevalence of abnormal glucose metabolism (AGM). We aimed to characterize AGM and clarify its association with Fontan pathophysiology. METHODS: We prospectively evaluated AGM with plasma glucose dynamics [mg/dL; fasting glucose (FPG), and maximum glucose increase (PG-spike)] during oral glucose tolerance test and hemoglobin A1c (HbA1c) in 276 consecutive Fontan patients (aged 19 ±â€¯7 years). Of these, 176 patients had serial AGM assessments with a mean interval of 6.5 years. RESULTS: Initial analysis revealed a high prevalence of impaired glucose tolerance (38.4%) and diabetes mellitus (DM) (4.7%), and positive family history, high HbA1c, and high central venous pressure independently predicted presence of DM. HbA1c was independently determined by hypersplenism and presence of DM (P < .05). Serial assessments revealed an increased PG-spike and a decreased HbA1c (P < .001 for both). Prevalence of DM increased (6.3% to 10.3%), and positive family history, high liver enzymes, and AGM predicted new onset of DM (P < .05 for all). Twenty-one patients died during 7.1-year follow-up. FPG (P < .01) and PG-spike (P < .05) independently predicted all-cause mortality. Particularly, patients with FPG ≤ 74 and/or PG-spike ≥85 had a mortality rate 8.7 times higher than those without (P = .0129). CONCLUSIONS: AGM progressed even in young adult Fontan patients, and HbA1c showed limited predictive value for progression. Oral glucose tolerance test plays important roles in uncovering unique Fontan AGM as well as predicting all-cause mortality.


Assuntos
Diabetes Mellitus/metabolismo , Jejum/sangue , Técnica de Fontan , Glucose/metabolismo , Hemoglobinas Glicadas/metabolismo , Adolescente , Adulto , Glicemia/metabolismo , Estudos de Casos e Controles , Causas de Morte , Criança , Estudos Transversais , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/mortalidade , Progressão da Doença , Feminino , Teste de Tolerância a Glucose , Cardiopatias Congênitas/metabolismo , Humanos , Hiperesplenismo/metabolismo , Hepatopatias/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Adulto Jovem
11.
Biomolecules ; 9(5)2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108896

RESUMO

A glutamate/NMDA receptor (NMDA-R) antagonist, amantadine (AMA) exhibits a broad spectrum of clinically important properties, including antiviral, antiparkinsonian, neuroprotective, neuro-reparative and cognitive-enhancing effects. However, both clinical and pre-clinical studies have demonstrated that noncompetitive NMDA-R antagonists induce severe schizophrenia-like cognitive deficits. Therefore, this study aims to clarify the clinical discrepancy between AMA and noncompetitive NMDA-R antagonists by comparing the effects of AMA with those of a noncompetitive NMDA-R antagonist, MK801, on rat tripartite glutamatergic synaptic transmission using microdialysis and primary cultured astrocytes. Microdialysis study demonstrated that the stimulatory effects of AMA on L-glutamate release differed from those of MK801 in the globus pallidus, entorhinal cortex and entopeduncular nucleus. The stimulatory effect of AMA on L-glutamate release was modulated by activation of cystine/glutamate antiporter (Sxc). Primary cultured astrocytes study demonstrated that AMA also enhanced glutathione synthesis via Sxc activation. Furthermore, carbon-monoxide induced damage of the astroglial glutathione synthesis system was repaired by AMA but not MK801. Additionally, glutamate/AMPA receptor (AMPA-R) antagonist, perampanel enhanced the protective effects of AMA. The findings of microdialysis and cultured astrocyte studies suggest that a combination of Sxc activation with inhibitions of ionotropic glutamate receptors contributes to neuroprotective, neuro-reparative and cognitive-enhancing activities that can mitigate several neuropsychiatric disorders.


Assuntos
Amantadina/farmacologia , Sistemas de Transporte de Aminoácidos Acídicos/agonistas , Astrócitos/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Sistemas de Transporte de Aminoácidos Acídicos/metabolismo , Animais , Astrócitos/metabolismo , Células Cultivadas , Maleato de Dizocilpina/farmacologia , Glutationa/metabolismo , Masculino , Nitrilas , Piridonas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Transmissão Sináptica
12.
Sex Dev ; 13(2): 60-66, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30739115

RESUMO

SRY-negative 46,XX testicular disorders of sex development (DSD) are very rare conditions. Recently, we identified a novel heterozygous NR5A1 mutation, p.Arg92Trp (c.274C>T, p.R92W), in 2 unrelated cases of 46,XX testicular/ovotesticular DSD. We report the clinical course from infancy to puberty in a Japanese male with SRY-negative 46,XX testicular DSD, carrying this p.Arg92Trp mutation in NR5A1. The patient naturally acquired the development of a penis and pubic hair during puberty. However, hypergonadotropic hypogonadism subsequently developed. More clinical cases will be needed to fully understand the effects of the p.Arg92Trp mutation on the ability to maintain testosterone secretion in 46,XX testicular DSD.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Mutação/genética , Puberdade/genética , Proteína da Região Y Determinante do Sexo/metabolismo , Fator Esteroidogênico 1/genética , Testículo/crescimento & desenvolvimento , Testículo/patologia , Transtornos 46, XX do Desenvolvimento Sexual/sangue , Adolescente , Criança , Pré-Escolar , Seguimentos , Heterozigoto , Humanos , Lactente , Masculino , Testosterona/sangue
13.
Neuropharmacology ; 156: 107547, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30802458

RESUMO

The selective α2A adrenoceptor agonist guanfacine reduces hyperactivity and improves cognitive impairment in patients with attention-deficit/hyperactivity disorder (ADHD). The major mechanisms of guanfacine have been considered to involve activation of postsynaptic α2A adrenoceptor in frontal pyramidal neurons. However, the effects of chronic guanfacine administration on catecholaminergic transmissions associated with the orbitofrontal cortex (OFC) remain unclear. To explore the mechanisms of action of guanfacine on catecholaminergic transmission, the effects of its acute local or sub-chronic systemic administration on catecholamine release within pathways from locus coeruleus (LC) to OFC and reticular thalamic nucleus (RTN), from RTN to mediodorsal thalamic nucleus (MDTN), and from MDTN to OFC were determined using multi-probe microdialysis with ultra-high performance liquid chromatography. Acute OFC local administration of guanfacine did not affect catecholamine release in OFC. Acute LC local and sub-chronic systemic administrations of guanfacine reduced norepinephrine release in LC, OFC and RTN, and also reduced GABA release in MDTN, whereas AMPA-induced (perfusion with AMPA into NDTN) releases of l-glutamate, norepinephrine and dopamine in OFC were enhanced by sub-chronic systemic guanfacine administration. This study identified that catecholaminergic transmission is composed of three pathways: direct noradrenergic and co-releasing catecholaminergic LC-OFC pathways and intermediate LC-OFC (LC-RTN-MDTN-OFC) pathway. We demonstrated the dual actions of guanfacine on catecholaminergic transmission: attenuation of direct noradrenergic LC-OFC transmission at the resting stage and enhancement of direct co-releasing catecholaminergic LC-OFC transmission via GABAergic disinhibition in the intermediate LC-OFC pathway. These dual actions of guanfacine probably contribute to clinical actions of guanfacine against ADHD and its comorbid symptoms. This article is part of the Special Issue entitled 'Current status of the neurobiology of aggression and impulsivity'.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Dopamina/metabolismo , Guanfacina/administração & dosagem , Norepinefrina/metabolismo , Córtex Pré-Frontal/metabolismo , Transmissão Sináptica , Animais , Núcleos Intralaminares do Tálamo/efeitos dos fármacos , Núcleos Intralaminares do Tálamo/metabolismo , Locus Cerúleo/efeitos dos fármacos , Locus Cerúleo/metabolismo , Masculino , Núcleo Mediodorsal do Tálamo/efeitos dos fármacos , Núcleo Mediodorsal do Tálamo/metabolismo , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Ratos Sprague-Dawley , Transmissão Sináptica/efeitos dos fármacos
14.
Oncotarget ; 9(52): 29934-29943, 2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-30042824

RESUMO

Distant metastasis remarkably worsens the prognoses of malignant melanoma patients. Toll-like receptors (TLRs) recognize molecules derived from many types of pathogens and activate the innate intravital immune system. In this study, we examined the effects of R848, a TLR7 ligand, on bone invasion by malignant melanoma cells. Mice underwent transplantation with cells of a malignant melanoma cell line B16F10, and were also administered R848 every three days. Hindlimbs were obtained 13 days after transplantation and invasion of bone marrow by B16F10 cells was evaluated. ELISA was used to determine the concentrations of cytokines in mouse serum and in the culture medium from bone marrow macrophages (BMMs) in the presence or absence of R848. In addition, MTS assays were used to examine the effects of media from BMM cultures on the proliferation of B16F10 cells. The rate of infiltration by B16F10 cells and the area of invasion were significantly reduced with R848 administration. Furthermore, serum levels of IL-6, IL-12, and IFN-γ were significantly increased in mice administered R848, with the same trend observed in the culture medium of BMMs treated with R848. In addition, B16F10 cell proliferation was suppressed by the addition of medium from cultured BMMs treated with R848. Neutralization by antibodies against IL-6, IL-12, and IFN-γ abrogated the suppression of proliferation of B16F10 cells by culture medium from BMMs treated with R848. Our results suggest that R848 drives the production of IL-6, IL-12, and IFN-γ in BMMs, which reduces proliferation and bone invasion by B16F10 cells.

15.
Sci Rep ; 8(1): 10579, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30002387

RESUMO

Monocarboxylate transporter-1 (MCT-1) is a transmembrane transporter for monocarboxylates including lactate and pyruvate. Silencing Mct1 by its small interfering RNA (siRNA) suppressed the expression of marker genes for osteoblast differentiation, namely, Tnap, Runx2, and Sp7, induced by BMP-2 in mouse myoblastic C2C12 cells. Mct1 siRNA also suppressed alkaline phosphatase activity, as well as expressions of Tnap and Bglap mRNAs in mouse primary osteoblasts. On the other hand, Mct1 siRNA did not have effects on the Smad1/5 or ERK/JNK pathways in BMP-2-stimulated C2C12 cells, while it up-regulated the mRNA expression of p53 (Trp53) as well as nuclear accumulation of p53 in C2C12 cells in a BMP-2-independent manner. Suppression of osteoblastic differentiation by Mct1 siRNA in C2C12 cells was abolished by co-transfection of Trp53 siRNA. Together, these results suggest that MCT-1 functions as a positive regulator of osteoblast differentiation via suppression of p53.


Assuntos
Diferenciação Celular , Transportadores de Ácidos Monocarboxílicos/metabolismo , Mioblastos/fisiologia , Osteoblastos/fisiologia , Simportadores/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/metabolismo , Linhagem Celular , Técnicas de Silenciamento de Genes , Camundongos , Transportadores de Ácidos Monocarboxílicos/genética , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Simportadores/genética
16.
Endocrinology ; 158(10): 3386-3398, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28977598

RESUMO

Rac1, a member of the small Rho GTPase family, plays multiple cellular roles. Studies of mice conditionally lacking Rac1 have revealed essential roles for Rac1 in various tissues, including cartilage and limb mesenchyme, where Rac1 loss produces dwarfism and long bone shortening. To gain further insight into the role of Rac1 in skeletal development, we have used transgenic mouse lines to express a constitutively active (ca) Rac1 mutant protein in a Cre recombinase-dependent manner. Overexpression of caRac1 in limb bud mesenchyme or chondrocytes leads to reduced body weight and shorter bones compared with control mice. Histological analysis of growth plates showed that caRac1;Col2-Cre mice displayed ectopic hypertrophic chondrocytes in the proliferative zone and enlarged hypertrophic zones. These mice also displayed a reduced proportion of proliferating cell nuclear antigen-positive cells in the proliferative zone and nuclear ß-catenin localization in the ectopic hypertrophic chondrocytes. Importantly, overexpression of caRac1 partially rescued the phenotypes of Rac1fl/fl;Col2-Cre and Rac1fl/fl;Prx1-Cre conditional knockout mice, including body weight, bone length, and growth plate disorganization. These results suggest that tight regulation of Rac1 activity is necessary for normal cartilage development.


Assuntos
Desenvolvimento Ósseo/genética , Osso e Ossos/patologia , Cartilagem/metabolismo , Neuropeptídeos/genética , Proteínas rac1 de Ligação ao GTP/genética , Animais , Western Blotting , Peso Corporal/genética , Osso e Ossos/metabolismo , Cartilagem/patologia , Condrócitos/metabolismo , Condrócitos/patologia , Feminino , Dosagem de Genes , Regulação da Expressão Gênica no Desenvolvimento , Lâmina de Crescimento , Hipertrofia , Imuno-Histoquímica , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Masculino , Mesoderma/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Tamanho do Órgão/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta Catenina/metabolismo
17.
FEBS Open Bio ; 7(9): 1410-1421, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28904869

RESUMO

Aldosterone synthase is the key rate-limiting enzyme in adrenal aldosterone production, and induction of its gene (CYP11B2) results in the progression of hypertension. As hypertension is a frequent complication among patients with diabetes, we set out to elucidate the link between diabetes mellitus and hypertension. We examined the effects of high glucose on CYP11B2 expression and aldosterone production using human adrenal H295R cells and a stable H295R cell line expressing a CYP11B2 5'-flanking region/luciferase cDNA chimeric construct. d-glucose (d-glu), but not its enantiomer l-glucose, dose dependently induced CYP11B2 transcription and mRNA expression. A high concentration (450 mg·dL-1) of d-glu time dependently induced CYP11B2 transcription and mRNA expression. Moreover, high glucose stimulated secretion of aldosterone into the media. Transient transfection studies using deletion mutants/nerve growth factor-induced clone B (NGFIB) response element 1 (NBRE-1) point mutant of CYP11B2 5'-flanking region revealed that the NBRE-1 element, known to be activated by transcription factors NGFIB and NURR1, was responsible for the high glucose-mediated effect. High glucose also induced the mRNA expression of these transcription factors, especially that of NURR1, but NURR1 knockdown using its siRNA did not affect high glucose-induced CYP11B2 mRNA expression. Taken together, it is speculated that high glucose may induce CYP11B2 transcription via the NBRE-1 element in its 5'-flanking region, resulting in the increase in aldosterone production although high glucose-induced NURR1 is not directly involved in the effect. Additionally, glucose metabolism and calcium channels were found to be involved in the high glucose effect. Our observations suggest one possible explanation for the high incidence of hypertension in patients with diabetes.

18.
Parasitol Int ; 66(6): 798-801, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28847744

RESUMO

Leeches belonging to the genus Ozobranchus are ectoparasitic on sea and freshwater turtles. The freshwater species O. jantseanus has been recorded from China and Japan. Ozobranchus jantseanus inhabiting Japan is considered to be a non-indigenous species, because their primary host, the Reeves' pond turtle, Mauremys reevesii, is thought to have been introduced in the last few centuries from adjacent Asian countries. To assess whether the Japanese populations of O. jantseanus were likely to have been introduced, their genetic diversity was investigated using mitochondrial cytochrome c oxidase subunit I sequences. The very low sequence diversity as well as the historical record of this species from Japan suggest that Japanese populations of O. jantseanus may have been artificially introduced along with their host turtles. Molecular phylogenies of COI showed that two marine Ozobranchus species formed a clade together with the freshwater O. jantseanus.


Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Sanguessugas/genética , Animais , Variação Genética , Interações Hospedeiro-Parasita , Espécies Introduzidas , Japão , Filogenia , Tartarugas/parasitologia
19.
PLoS One ; 12(8): e0181055, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28800627

RESUMO

The effects of retinoids on adrenal aldosterone synthase gene (CYP11B2) expression and aldosterone secretion are still unknown. We therefore examined the effects of nuclear retinoid X receptor (RXR) pan-agonist PA024 on CYP11B2 expression, aldosterone secretion and blood pressure, to elucidate its potential as a novel anti-hypertensive drug. We demonstrated that PA024 significantly suppressed angiotensin II (Ang II)-induced CYP11B2 mRNA expression, promoter activity and aldosterone secretion in human adrenocortical H295R cells. Human CYP11B2 promoter functional analyses using its deletion and point mutants indicated that the suppression of CYP11B2 promoter activity by PA024 was in the region from -1521 (full length) to -106 including the NBRE-1 and the Ad5 elements, and the Ad5 element may be mainly involved in the PA024-mediated suppression. PA024 also significantly suppressed the Ang II-induced mRNA expression of transcription factors NURR1 and NGFIB that bind to and activate the Ad5 element. NURR1 overexpression demonstrated that the decrease of NURR1 expression may contribute to the PA024-mediated suppression of CYP11B2 transcription. PA024 also suppressed the Ang II-induced mRNA expression of StAR, HSD3ß2 and CYP21A2, a steroidogenic enzyme group involved in aldosterone biosynthesis. Additionally, the PA024-mediated CYP11B2 transcription suppression was shown to be exerted via RXRα. Moreover, the combination of PPARγ agonist pioglitazone and PA024 caused synergistic suppressive effects on CYP11B2 mRNA expression. Finally, PA024 treatment significantly lowered both the systolic and diastolic blood pressure in Tsukuba hypertensive mice (hRN8-12 x hAG2-5). Thus, RXR pan-agonist PA024 may be a candidate anti-hypertensive drugs that acts via the suppression of aldosterone synthesis and secretion.


Assuntos
2-Naftilamina/análogos & derivados , Córtex Suprarrenal/metabolismo , Aldosterona/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Citocromo P-450 CYP11B2/metabolismo , Pirimidinas/farmacologia , Receptores X de Retinoides/antagonistas & inibidores , 2-Naftilamina/farmacologia , Córtex Suprarrenal/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP11B2/genética , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hidrocortisona/metabolismo , Íons , Camundongos Transgênicos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Pioglitazona , Mutação Puntual/genética , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores X de Retinoides/metabolismo , Deleção de Sequência/genética , Esteroides/biossíntese , Tiazolidinedionas/farmacologia
20.
Nanomedicine ; 13(8): 2545-2553, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28754466

RESUMO

Although empirical findings have indicated increase in bone fracture risk in type 2 diabetes patients, that has yet to be proven by results obtained at the material level. Here, we report evidence showing nanoscale time-dependent deformation/recovery of in vitro calcified nodules mimicking bone turnover in type 2 diabetes in respect to methylglyoxal (MG)-induced glycation. Nanoindentation test results revealed that calcified nodules cultured with MG did not show adequate dimensional recovery, despite a large creep rate during constant load indentation testing. This lesser recovery is likely based on the linear matrix polymerization network formed by advanced glycation end products (AGEs) as a secondary product of MG. Since elevated serum MG and abnormal bone turnover related to the amount of AGEs are observed in cases of type 2 diabetes, this time-dependent behavior may be one of the factors of the bone fracture mechanism at the material level in affected patients.


Assuntos
Calcinose/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Osteoblastos/metabolismo , Aldeído Pirúvico/metabolismo , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Calcinose/patologia , Linhagem Celular , Proliferação de Células , Diabetes Mellitus Tipo 2/patologia , Humanos , Osteoblastos/citologia , Osteoblastos/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...