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1.
Int J Mol Sci ; 20(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934765

RESUMO

Both adiponectin and secreted protein, acidic and rich in cysteine (SPARC) inhibit platelet-derived growth factor-BB (PDGF-BB)-induced and basic fibroblast growth factor (FGF2)-induced angiogenic activities through direct and indirect interactions. Although SPARC enhances nerve growth factor (NGF)-dependent neurogenesis, the physical interaction of NGFß with adiponectin and SPARC remains obscure. Therefore, we first examined their intermolecular interaction by surface plasmon resonance method. NGFß bound to immobilized SPARC with the binding constant of 59.4 nM, comparable with that of PDGF-BB (24.5 nM) but far less than that of FGF2 (14.4 µM). NGFß bound to immobilized full length adiponectin with the binding constant of 103 nM, slightly higher than those of PDGF-BB (24.3 nM) and FGF2 (80.2 nM), respectively. Treatment of PC12 cells with SPARC did not cause mitogen-activated protein kinase (MAPK) activation and neurite outgrowth. However, simultaneous addition of SPARC with NGFß enhanced NGFß-induced MAPK phosphorylation and neurite outgrowth. Treatment of the cells with adiponectin increased AMP-activated protein kinase (AMPK) phosphorylation but failed to induce neurite outgrowth. Simultaneous treatment with NGFß and adiponectin significantly reduced cell size and the number of cells with neurite, even after silencing the adiponectin receptors by their siRNA. These results indicate that NGFß directly interacts with adiponectin and SPARC, whereas these interactions oppositely regulate NGFß functions.


Assuntos
Adiponectina/metabolismo , Fator de Crescimento Neural/metabolismo , Osteonectina/metabolismo , Animais , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Camundongos , Crescimento Neuronal , Células PC12 , Ratos , Receptor de Fator de Crescimento Neural/metabolismo
2.
Am J Physiol Endocrinol Metab ; 309(2): E177-90, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26015437

RESUMO

Despite significant reduction of cardiovascular events by statin treatment, substantial residual risk persists, driving emerging needs for the development of new therapies. We identified a novel cholesteryl ester transfer protein (CETP) inhibitor, K-312, that raises HDL and lowers LDL cholesterol levels in animals. K-312 also suppresses hepatocyte expression of proprotein convertase subtilisin/kexin 9 (PCSK9), a molecule that increases LDL cholesterol. We explored the underlying mechanism for the reduction of PCSK9 expression by K-312. K-312 inhibited in vitro human plasma CETP activity (IC50; 0.06 µM). Administration of K-312 to cholesterol-fed New Zealand White rabbits for 18 wk raised HDL cholesterol, decreased LDL cholesterol, and attenuated aortic atherosclerosis. Our search for additional beneficial characteristics of this compound revealed that K-312 decreases PCSK9 expression in human primary hepatocytes and in the human hepatoma cell line HepG2. siRNA silencing of CETP in HepG2 did not compromise the suppression of PCSK9 by K-312, suggesting a mechanism independent of CETP. In HepG2 cells, K-312 treatment decreased the active forms of sterol regulatory element-binding proteins (SREBP-1 and -2) that regulate promoter activity of PCSK9. Chromatin immunoprecipitation assays demonstrated that K-312 decreased the occupancy of SREBP-1 and SREBP-2 on the sterol regulatory element of the PCSK9 promoter. PCSK9 protein levels decreased by K-312 treatment in the circulating blood of cholesterol-fed rabbits, as determined by two independent mass spectrometry approaches, including the recently developed, highly sensitive parallel reaction monitoring method. New CETP inhibitor K-312 decreases LDL cholesterol and PCSK9 levels, serving as a new therapy for dyslipidemia and cardiovascular disease.


Assuntos
Anticolesterolemiantes/farmacologia , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , LDL-Colesterol/metabolismo , Pró-Proteína Convertases/genética , Serina Endopeptidases/genética , Animais , Células Cultivadas , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/metabolismo , Coelhos , Ratos , Ratos Sprague-Dawley , Serina Endopeptidases/metabolismo
3.
Horm Behav ; 66(2): 317-23, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24937437

RESUMO

Orexin acts as an orexigenic factor for the regulation of appetite and rhythmicity in rodents. In goldfish, intracerebroventricular (ICV) administration of orexin A has been shown to affect not only food intake, but also locomotor activity. However, as there is still no information regarding the effect of orexin A on emotional behavior in goldfish, we investigated the effect of orexin A on psychomotor activity in this species. Intracerebroventricular administration of synthetic orexin A at 2 and 4pmol/g body weight (BW) enhanced locomotor activity, and this enhancement by orexin A at 4pmol/g BW was attenuated by treatment with the orexin receptor 1 antagonist, SB334867, at 10pmol/g BW. Since intact goldfish prefer a black to a white background area, or the lower to the upper area of a tank, we used two types of preference tests (black/white and upper/lower tests) for measuring anxiety-like behavior in goldfish. Intracerebroventricular administration of orexin A at 4pmol/g BW shortened the time spent in the white background area, and increased the time taken to move from the lower to the upper area. This action of orexin A mimicked that of the central-type benzodiazepine receptor inverse agonist, FG-7142 (an anxiogenic agent), at 4pmol/g BW. The anxiogenic-like effect of orexin A was abolished by treatment with SB334867 at 10pmol/g BW. These results indicate that orexin A potently affects psychomotor activity in goldfish.


Assuntos
Ansiedade/induzido quimicamente , Ansiedade/psicologia , Carpa Dourada/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Atividade Motora/efeitos dos fármacos , Neuropeptídeos/farmacologia , Animais , Benzoxazóis/farmacologia , Carbolinas/farmacologia , Diazepam/farmacologia , Emoções/efeitos dos fármacos , Hipnóticos e Sedativos/farmacologia , Injeções Intraventriculares , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Naftiridinas , Neuropeptídeos/antagonistas & inibidores , Orexinas , Ureia/análogos & derivados , Ureia/farmacologia
4.
Food Chem X ; 21: 101231, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38420508

RESUMO

Sesame is a frequent cause of adverse food reactions in allergic patients. We developed a novel sandwich enzyme-linked immunosorbent assay (ELISA) using two monoclonal antibodies and a unique extraction buffer for the detection and quantification of sesame proteins in processed foods and in raw food ingredients to clarify the validity of sesame labeling and for precautionary allergen labeling. The developed sandwich ELISA method is highly specific for sesame proteins. The limit of detection (LOD) and limit of quantification (LOQ) are 0.013 µg/g and 0.025 µg/g, respectively. The recoveries for incurred food samples, such as dressing, breads, sauce and pudding, ranged from 67 % to 81 %, while the repeatability and reproducibility coefficients of variation were less than 4.7 % and 4.5 %, respectively. The developed method has applicability for food products and is a reliable tool for the detection of hidden sesame proteins in raw food ingredients and in processed foods.

5.
Gen Comp Endocrinol ; 188: 118-22, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23321398

RESUMO

Corticotropin-releasing hormone (CRH) is a member of the hypothalamic neuropeptide family that includes urocortins, urotensin I and sauvagine in vertebrates. CRH and urocortin act as anorexigenic factors for satiety regulation in rodents. In a goldfish model, intracerebroventricular (ICV) administration of ovine CRH (oCRH) affects not only food intake, but also locomotor activity. However, there is no information regarding the psychophysiological roles of CRH in goldfish. Therefore, we investigated the effect of oCRH on psychomotor activity in this species. ICV administration of synthetic oCRH at 20 pmol/g body weight (BW) enhanced locomotor activity. Since intact goldfish prefer the lower to the upper area of a tank, we developed a method for measuring the time taken for fish to move from the lower to the upper area. ICV administration of oCRH at 20 pmol/g BW and the central-type benzodiazepine receptor inverse agonist FG-7142 (an anxiogenic agent) at 1-4 pmol/g BW both increased the time taken to move from the lower to the upper area. This anxiogenic-like effect of oCRH was abolished by the CRH receptor antagonist α-helical CRH(9-41) (100 pmol/g BW). These results indicate that CRH can potently affect locomotor and psychomotor activities in goldfish.


Assuntos
Ansiolíticos/farmacologia , Hormônio Liberador da Corticotropina/farmacologia , Carpa Dourada/fisiologia , Animais , Carbolinas/farmacologia , Locomoção/efeitos dos fármacos , Ovinos
6.
Jpn J Vet Res ; 60(1): 5-13, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22458193

RESUMO

The metabolic mechanisms to circannual changes in body mass of bears have yet to be elucidated. We hypothesized that the Japanese black bear (Ursus thibetanus japonicus) has a metabolic mechanism that efficiently converts carbohydrates into body fat by altering insulin sensitivity during the hyperphagic stage before hibernation. To test this hypothesis, we investigated the changes in blood biochemical values and glucose and insulin responses to intravenous glucose tolerance tests (IVGTT) during the active season (August, early and late November). Four, adult, female bears (5-17 years old) were anesthetized with 6 mg/kg TZ (tiletamine HCl and zolazepam HCl) in combination with 0.1 mg/kg acepromazine maleate. The bears were injected intravenously with glucose (0.5 g/kg of body mass), and blood samples were obtained before, at, and intermittently after glucose injection. The basal triglycerides concentration decreased significantly with increase in body mass from August to November. Basal levels of plasma glucose and serum insulin concentrations were not significantly different among groups. The results of IVGTT demonstrated the increased peripheral insulin sensitivity and glucose tolerance in early November. In contrast, peripheral insulin resistance was indicated by the exaggerated insulin response in late November. Our findings suggest that bears shift their glucose and lipid metabolism from the stage of normal activity to the hyperphagic stage in which they show lipogenic-predominant metabolism and accelerate glucose uptake by increasing the peripheral insulin sensitivity.


Assuntos
Glicemia/fisiologia , Teste de Tolerância a Glucose/veterinária , Insulina/sangue , Insulina/metabolismo , Ursidae/sangue , Tecido Adiposo/fisiologia , Animais , Metabolismo dos Carboidratos/fisiologia , Feminino , Resistência à Insulina/fisiologia , Japão , Estações do Ano
7.
Cell Rep ; 39(2): 110685, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35417712

RESUMO

Cellular heterogeneity of aortic valves complicates the mechanistic evaluation of the calcification processes in calcific aortic valve disease (CAVD), and animal disease models are lacking. In this study, we identify a disease-driver population (DDP) within valvular interstitial cells (VICs). Through stepwise single-cell analysis, phenotype-guided omic profiling, and network-based analysis, we characterize the DDP fingerprint as CD44highCD29+CD59+CD73+CD45low and discover potential key regulators of human CAVD. These DDP-VICs demonstrate multi-lineage differentiation and osteogenic properties. Temporal proteomic profiling of DDP-VICs identifies potential targets for therapy, including MAOA and CTHRC1. In vitro loss-of-function experiments confirm our targets. Such a stepwise strategy may be advantageous for therapeutic target discovery in other disease contexts.


Assuntos
Estenose da Valva Aórtica , Calcinose , Animais , Valva Aórtica/patologia , Células Cultivadas , Proteínas da Matriz Extracelular , Humanos , Osteogênese , Proteômica
8.
J AOAC Int ; 93(4): 1255-61, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20922960

RESUMO

Because food allergens from tree nuts, including walnuts, are a frequent cause of adverse food reactions for allergic patients, the labeling of foods containing ingredients derived from tree nuts is required in numerous countries. According to Japanese regulations, the labeling of food products containing walnuts is recommended. To ensure proper labeling, a novel sandwich ELISA kit for the determination of walnut protein in processed foods (Walnut Protein [2S-Albumin] Kit; Morinaga Institute of Biological Science, Inc.; "walnut kit") has been developed. We prepared seven types of incurred samples (model processed foods: biscuits, bread, sponge cake, orange juice, jelly, chicken meatballs, and rice gruel) containing 10 microg walnut soluble protein/g of food for use in interlaboratory evaluations of the walnut kit. The walnut kit displayed sufficient reproducibility relative standard deviations (interlaboratory precision: 5.8-9.9% RSDR) and a high level of recovery (81-119%) for all the incurred samples. All the repeatability relative standard deviation (RSDr) values for the incurred samples that were examined were less than 6.0%. The results of this interlaboratory evaluation suggested that the walnut kit could be used as a precise and reliable tool for determination of walnut protein in processed foods.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Juglans/química , Proteínas de Plantas/análise , Calibragem , Laboratórios , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes
9.
J Vet Med Sci ; 72(6): 809-11, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20145380

RESUMO

The plasma leptin concentration was evaluated in dogs with diabetes mellitus. Twenty normal and sixteen diabetic dogs were divided into nonobese and obese groups based on body condition score, respectively. The obese normal dogs had significantly higher plasma leptin concentrations than the nonobese normal dogs, whereas there was no significant difference between the nonobese and obese diabetic dogs. In addition, the plasma leptin concentration in the obese diabetic dogs was significantly lower than that in the obese normal dogs. In conclusion, the plasma leptin concentrations in the diabetic dogs were affected by factors other than adiposity.


Assuntos
Diabetes Mellitus/veterinária , Doenças do Cão/sangue , Leptina/sangue , Animais , Glicemia/metabolismo , Colesterol/sangue , Diabetes Mellitus/sangue , Cães , Feminino , Insulina/sangue , Masculino , Obesidade/sangue , Obesidade/complicações , Obesidade/veterinária , Valores de Referência , Triglicerídeos/sangue
10.
J Vet Med Sci ; 71(7): 1005-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19652495

RESUMO

A novel sandwich enzyme-linked immunosorbent assay (ELISA) was established to determine the serum insulin concentrations in domestic cats. By using a solid-phase mouse anti-bovine insulin monoclonal antibody and a peroxidase-conjugated guinea pig anti-rat insulin polyclonal antibody, feline serum insulin concentrations in the range of 0.1 to 3.6 ng/ml could be measured. The intraassay CV and interassay CV were less than 6% and less than 10%, respectively. The present insulin assay will strongly help studies on feline diabetes mellitus.


Assuntos
Gatos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Insulina/sangue , Animais , Glicemia , Bovinos , Feminino , Masculino , Camundongos , Ratos , Sensibilidade e Especificidade
11.
J Neuroendocrinol ; 31(1): e12667, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30521069

RESUMO

Sulphated cholecystokinin octapeptide (CCK-8s) is involved in feeding regulation as an anorexigenic neuropeptide in vertebrates. In rodents, i.c.v. administration of CCK-8s has been shown to affect not only feeding behaviour, but also psychomotor activity. However, there is still no information available concerning the psychophysiological effects of CCK-8s in goldfish. Therefore, in the present study, we examined the effect of synthetic goldfish (gf) CCK-8s on psychomotor activity in this species. Intracerebroventricular administration of gfCCK-8s at 0.1, 0.5 and 2.5 pmol g-1 body weight (BW) did not affect swimming distance (locomotor activity). Because goldfish prefer the lower to the upper area of a tank, we used this as a preference test (upper/lower test) to assess anxiety-like behaviour. Intracerebroventricular administration of gfCCK-8s at 2.5 pmol g-1 BW shortened the time spent in the upper area. The action of gfCCK-8s mimicked that of FG-7142 (the central-type benzodiazepine receptor inverse agonist, an anxiogenic agent) at 5 and 10 pmol g-1 BW. The anxiogenic-like effect of gfCCK-8s was abolished by treatment with the CCK receptor antagonist proglumide at 50 pmol g-1 BW. We also investigated the localisation of CCK/gastrin-like immunoreactivity in the goldfish brain. CCK/gastrin-like immunoreactivity was observed in the anxiety-related regions (the nucleus habenularis and the interpeduncular nucleus). These data indicate that gfCCK-8s potently affects psychomotor activity in goldfish, and exerts an anxiogenic-like effect via the CCK receptor-signalling pathway.


Assuntos
Ansiedade/fisiopatologia , Carpa Dourada/fisiologia , Desempenho Psicomotor/fisiologia , Sincalida/fisiologia , Animais , Ansiedade/induzido quimicamente , Carbolinas/administração & dosagem , Feminino , Injeções Intraventriculares , Locomoção/efeitos dos fármacos , Masculino , Proglumida/administração & dosagem , Desempenho Psicomotor/efeitos dos fármacos , Sincalida/administração & dosagem
12.
J Vet Med Sci ; 70(12): 1399-403, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19122415

RESUMO

In the present study, assay of the serum leptin concentration of the Japanese black bear (Ursus thibetanus japonicus) was attempted using a canine-leptin-specific sandwich enzyme-linked immunosorbent assay (ELISA). The dose-response curve of the bear serum was linear and parallel to the canine leptin standard curve. In mated and unmated bears, the serum leptin concentration was stable at low levels from May to August or September, gradually increased from September or October, and then remarkably increased in late November. We conclude that this method may be useful for measuring bear serum leptin concentration and that the serum leptin concentration changes annually with a peak in late November.


Assuntos
Leptina/sangue , Ursidae/fisiologia , Animais , Animais de Zoológico , Feminino , Fatores de Tempo
13.
Biochem Pharmacol ; 73(4): 550-60, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17147953

RESUMO

Increasing lines of evidence show that resveratrol, a polyphenol compound contained in several dietary products, exhibits cytoprotective actions. Notably, resveratrol activates sirtuin family of NAD-dependent histone deacetylases implicated in regulation of various cellular processes including gene transcription, DNA repair and apoptosis. Here we examined neuroprotective effect of resveratrol on dopaminergic neurons in organotypic midbrain slice culture. Resveratrol and quercetin, another sirtuin-activating polyphenol, prevented the decrease of dopaminergic neurons and the increase of propidium iodide uptake into slices induced by a dopaminergic neurotoxin 1-methyl-4-phenyl pyridinium (MPP(+)). Resveratrol also provided concentration-dependent neuroprotective effects against sodium azide, a mitochondrial complex IV inhibitor, and thrombin (EC number 3.4.21.5), a microglia-activating agent. Sirtuin inhibitors such as nicotinamide and sirtinol did not attenuate the protective effect of resveratrol against MPP(+) cytotoxicity. Instead, we found that resveratrol prevented accumulation of reactive oxygen species, depletion of cellular glutathione, and cellular oxidative damage induced by MPP(+), suggesting involvement of antioxidative properties in the neuroprotective action of resveratrol. On the other hand, resveratrol as well as a sirtuin activator NAD inhibited dopaminergic neurotoxicity of a DNA alkylating agent, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Moreover, MNNG-induced increase in acetylation of p53, a representative target of sirtuin deacetylase activity, was suppressed by resveratrol. These results indicate that resveratrol can exert neuroprotective actions in dopaminergic neurons. Either antioxidative activity or sirtuin-activating potential may play an important role in the neuroprotectice actions of resveratrol against different kinds of insults.


Assuntos
Dopamina/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estilbenos/farmacologia , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Animais Recém-Nascidos , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/toxicidade , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Mesencéfalo/citologia , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Metilnitronitrosoguanidina/toxicidade , Neurônios/metabolismo , Niacinamida/farmacologia , Técnicas de Cultura de Órgãos , Quercetina/farmacologia , Ratos , Ratos Wistar , Resveratrol , Sirtuína 1 , Sirtuínas/metabolismo , Sirtuínas/farmacologia , Azida Sódica/toxicidade , Trombina/toxicidade , Proteína Supressora de Tumor p53/metabolismo
14.
Biochim Biophys Acta ; 1644(1): 9-15, 2004 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-14741740

RESUMO

Induction of E-selectin on endothelial cell surface initiates leukocyte adhesion and subsequent migration into the subendothelium. Here, we tested the effect of hepatocyte growth factor (HGF) on inflammatory cytokine-induced expression of E-selectin and consequent leukocyte-endothelial cell interaction using human umbilical vein endothelial cells (HUVEC). Prior treatment of HUVEC with HGF significantly attenuated the tumor necrosis factor (TNF)-alpha-induced E-selectin protein, adhesion of HL60 cells to HUVEC and E-selectin mRNA expression in a dose-dependent manner, while HGF itself did not exert any effects. The HGF effects on the mRNA expression were inhibited in the presence of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, which also abolished HGF-stimulated eNOS activity. These results suggest HGF plays cardiovascular protective functions mediated, at least in part, through nitric oxide-dependent suppression of inflammatory cytokine-induced E-selectin expression and subsequent tethering of leukocytes to endothelial cells.


Assuntos
Selectina E/biossíntese , Endotélio/metabolismo , Fator de Crescimento de Hepatócito/farmacologia , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio/efeitos dos fármacos , Células HL-60 , Fator de Crescimento de Hepatócito/fisiologia , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo III , RNA Mensageiro/biossíntese , Fator de Necrose Tumoral alfa/antagonistas & inibidores
15.
Nutrition ; 21(5): 594-601, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15850966

RESUMO

OBJECTIVE: We previously found that ingested cocoa decreased visceral adipose tissue weight in rat. To elucidate the molecular mechanisms of that effect, we carried out experiments aimed at analyzing biochemical parameters and gene expression profiles. METHODS: Rats were fed either of two high-fat diets, differing only in supplementation with real or mimetic cocoa. On day 21, body weights, mesenteric white adipose tissue weights, and concentrations of serum triacylglycerol were measured. To investigate the molecular mechanisms underlying the effects of cocoa on lipid metabolism and triacylglycerol accumulation, we examined gene expression profiles in liver and mesenteric white adipose tissues using the GeneChip microarray system. RESULTS: Final body weights and mesenteric white adipose tissue weights were significantly lower in rats fed the real cocoa diet than in those fed the mimetic cocoa diet (P<0.05), and serum triacylglycerol concentrations tended to be lower in rats fed the real cocoa diet (P=0.072). DNA microarray analysis showed that cocoa ingestion suppressed the expression of genes for enzymes involved in fatty acid synthesis in liver and white adipose tissues. In white adipose tissue, cocoa ingestion also decreased the expression of genes for fatty acid transport-relating molecules, whereas it upregulated the expression of genes for uncoupling protein-2 as a thermogenesis factor. CONCLUSIONS: Ingested cocoa can prevent high-fat diet-induced obesity by modulating lipid metabolism, especially by decreasing fatty acid synthesis and transport systems, and enhancement of part of the thermogenesis mechanism in liver and white adipose tissue.


Assuntos
Tecido Adiposo/metabolismo , Cacau , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Fígado/metabolismo , Obesidade/prevenção & controle , Animais , Peso Corporal/efeitos dos fármacos , Cacau/metabolismo , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/metabolismo , Regulação Enzimológica da Expressão Gênica , Fígado/enzimologia , Masculino , Obesidade/etiologia , Obesidade/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Distribuição Aleatória , Ratos , Ratos Wistar , Triglicerídeos/sangue
16.
Res Vet Sci ; 79(2): 169-75, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15924935

RESUMO

The objective of this study was to evaluate, in dogs, the effects of obesity and weight loss on plasma total ghrelin and leptin concentrations. Twenty-four Beagle dogs, 12 control lean and 12 obese dogs of both genders and aged between 1 and 9 years, were used for the experiments. Mean body weight was 12.7+/-0.7 kg for the lean group and 21.9+/-0.8 kg for the obese group. The trial was divided into three phases. During phase 1, all 24 Beagle dogs were fed a maintenance diet. During phase 2, the obese dogs were submitted to a weight loss protocol with a high protein-low energy diet. The weight loss protocol ended once dogs reached optimal body weight. During phase 3, the dogs that were submitted to the weight loss protocol were maintained at their optimal body weight for 6 months. Plasma total ghrelin, leptin, insulin and glucose concentrations were measured to evaluate the effects of obesity and weight loss on these parameters in dogs. Body weight, body condition score, thoracic and pelvic perimeters, and ingested food amounts were also recorded during the study. Obese dogs demonstrated a significant decrease in plasma ghrelin and a significant increase in plasma leptin and insulin concentrations when compared with control dogs. During weight loss, significant increases in plasma total ghrelin and glucose and significant decreases in plasma leptin and insulin were observed. The increase in plasma ghrelin concentrations seemed to be transient. Body weight and the morphometric parameters correlated positively with leptin concentrations and negatively with total ghrelin concentrations. These results suggest that ghrelin and leptin could play a role in dogs in the adaptation to a positive or negative energy balance, as observed in humans.


Assuntos
Doenças do Cão/sangue , Leptina/sangue , Obesidade/veterinária , Hormônios Peptídicos/sangue , Animais , Glicemia , Doenças do Cão/fisiopatologia , Cães , Feminino , Grelina , Insulina/sangue , Masculino , Obesidade/sangue , Obesidade/fisiopatologia , Redução de Peso/fisiologia
17.
Neurosci Lett ; 341(2): 123-6, 2003 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12686381

RESUMO

Excitatory neuronal activity produces beneficial influences on neuronal survival under several circumstances. We show that cultivation of rat midbrain slices in the presence of elevated extracellular Mg(2+) resulted in a marked decrease in the number of dopaminergic neurons. The effect was prominent when Mg(2+) was added to the medium during the first week of cultivation. Chronic treatment with antagonists of N-methyl-D-aspartate receptors such as 2-amino-5-phosphonovaleric acid, MK-801 and ifenprodil also resulted in a marked loss of dopaminergic neurons, whereas nicotinic receptor antagonists showed no effect. The effect of MK-801 was abolished by chronic depolarization by elevated extracellular K(+), or by application of forskolin or dibutyryl cyclic AMP. Thus, tonic activation of N-methyl-D-aspartate receptors driven by neuronal activity may play an important role in the maintenance of dopaminergic neurons.


Assuntos
Dopamina/metabolismo , Mesencéfalo/metabolismo , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Animais Recém-Nascidos , Colforsina/farmacologia , Técnicas de Cultura , Maleato de Dizocilpina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Antagonistas de Aminoácidos Excitatórios/farmacologia , Imuno-Histoquímica , Magnésio/farmacologia , Mesencéfalo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Piperidinas/farmacologia , Potássio/farmacologia , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Sódio/farmacologia , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
18.
J Vet Med Sci ; 64(4): 349-53, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12014581

RESUMO

Leptin is a protein synthesized and secreted primarily by adipocytes, and the circulating leptin concentration is elevated in obese humans and rodents. Recently, we have established a sandwich enzyme-linked immunosorbent assay for canine leptin. In the present study, plasma leptin concentrations were measured in experimentally developed obese beagles and in clinically obese dogs. When 5 male beagles were given a high-energy diet for 3 months, all of them became obese and the plasma leptin concentration significantly increased from 2.4+/-1.2 to 4.9+/-0.9 ng/ml, positively correlating with body fat content estimated by the deuterium oxide dilution method (r=0.87). The leptin concentrations of plasma samples collected from 59 dogs in veterinary practices were compared with their body condition scores (BCS). The plasma leptin concentrations of obese dogs were 9.7+/-0.7 and 12.3+/-1.5 ng/ml at BCS=4 and BCS=5, respectively, which were significantly higher than those of optimal (BCS=3) dogs (2.7+/-0.3 ng/ml). There was no significant effect of sex and breed. A weak positive correlation (r=0.37) was found between the plasma leptin concentration and age, probably due to the lesser content of visceral fat in puppies younger than 1 year old. These results indicate that plasma leptin is a good index of adiposity in dogs regardless of breed, age and sex, and may be useful for quantitative assessment of obesity in small animal practice.


Assuntos
Doenças do Cão/sangue , Leptina/sangue , Obesidade/veterinária , Animais , Peso Corporal , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leptina/metabolismo , Masculino , Obesidade/sangue , Análise de Regressão
19.
J Vet Med Sci ; 65(11): 1207-11, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14665750

RESUMO

Leptin is a protein synthesized and secreted primarily by adipose tissue. The blood leptin concentration is known to reflect body fat content in rodents, humans and dogs, and thereby is useful for quantitative assessment of obesity. In the present study, we produced recombinant feline leptin in Escherichia coli transfected with feline leptin cDNA we cloned previously. The recombinant feline leptin with a molecular weight of 16 kDa induced phosphorylation of the signal transducers and activators of transcription 3 (STAT3) protein in the cells expressing rat leptin receptor. The anti-feline leptin antibody raised in rabbits reacted well to feline and human leptin and less to rodents' leptin in Western blot analysis. Sandwich enzyme-linked immunosorbent assay (ELISA) was developed, using rabbit anti-feline leptin antibody and recombinant feline leptin as a standard. In this ELISA system, cross-reactivity to human, rat and mouse leptin was 30.7%, 69.5% and 66.6%, respectively. The plasma leptin levels of 24 healthy cats were in a range from 0.3 to 29.7 ng/ml with the mean +/- SEM of 4.5 +/- 1.3 ng/ml, being positively proportional to body fat content. These results indicate that our ELISA system may be useful for assessment of obesity in cats.


Assuntos
Doenças do Gato/diagnóstico , Leptina/imunologia , Obesidade/veterinária , Proteínas Recombinantes/imunologia , Animais , Formação de Anticorpos/imunologia , Western Blotting , Células CHO , Gatos , Cricetinae , Cricetulus , Proteínas de Ligação a DNA/metabolismo , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Leptina/sangue , Leptina/metabolismo , Obesidade/diagnóstico , Coelhos , Proteínas Recombinantes/sangue , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT3 , Transdução de Sinais , Transativadores/metabolismo
20.
PLoS One ; 9(5): e96005, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24797675

RESUMO

Statins exert atheroprotective effects through the induction of specific transcriptional factors in multiple organs. In endothelial cells, statin-dependent atheroprotective gene up-regulation is mediated by Kruppel-like factor (KLF) family transcription factors. To dissect the mechanism of gene regulation, we sought to determine molecular targets by performing microarray analyses of human umbilical vein endothelial cells (HUVECs) treated with pitavastatin, and KLF4 was determined to be the most highly induced gene. In addition, it was revealed that the atheroprotective genes induced with pitavastatin, such as nitric oxide synthase 3 (NOS3) and thrombomodulin (THBD), were suppressed by KLF4 knockdown. Myocyte enhancer factor-2 (MEF2) family activation is reported to be involved in pitavastatin-dependent KLF4 induction. We focused on MEF2C among the MEF2 family members and identified a novel functional MEF2C binding site 148 kb upstream of the KLF4 gene by chromatin immunoprecipitation along with deep sequencing (ChIP-seq) followed by luciferase assay. By applying whole genome and quantitative chromatin conformation analysis {chromatin interaction analysis with paired end tag sequencing (ChIA-PET), and real time chromosome conformation capture (3C) assay}, we observed that the MEF2C-bound enhancer and transcription start site (TSS) of KLF4 came into closer spatial proximity by pitavastatin treatment. 3D-Fluorescence in situ hybridization (FISH) imaging supported the conformational change in individual cells. Taken together, dynamic chromatin conformation change was shown to mediate pitavastatin-responsive gene induction in endothelial cells.


Assuntos
Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fatores de Transcrição Kruppel-Like/biossíntese , Quinolinas/farmacologia , Cromatina/genética , Regulação da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/genética , Elementos de Resposta , Trombomodulina/biossíntese , Trombomodulina/genética
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