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1.
Eur J Pharmacol ; 640(1-3): 243-9, 2010 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-20478303

RESUMO

Coenzyme A (CoA):diacylglycerol acyltransferase 1 (DGAT1) is 1 of the 2 known DGAT enzymes that catalyze the final and only committed step in triacylglycerol synthesis; this enzyme is considered to be a potential therapeutic target in metabolic disorders such as obesity and its related lipid abnormalities. Compound-Z, a novel specific small-molecule DGAT1 inhibitor, significantly reduced adipose tissue weight and tended to hepatic lipid accumulation in genetically obese KKAy mice. These actions were shown to almost the same extent in both a high-fat feeding condition in which triacylglycerols are synthesized mainly via exogenous fatty acid and a low-fat, high-carbohydrate feeding condition in which triacylglycerols are synthesized mainly via de novo fatty acid synthesis. This inhibitor also significantly reduced plasma and/or hepatic cholesterol levels in KKAy mice in a high-fat feeding condition. This cholesterol-lowering effect was suggested to be due to mainly decreases in cholesterol absorption from the small intestine. These results suggest that Compound-Z is a promising and attractive agent not only for the treatment of obesity but also hepatic steatosis and circulating lipid abnormalities that are the leading causes of atherosclerosis.


Assuntos
Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Carboidratos da Dieta/efeitos adversos , Gorduras na Dieta/efeitos adversos , Inibidores Enzimáticos/farmacologia , Fígado Gorduroso/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Absorção/efeitos dos fármacos , Adiposidade/efeitos dos fármacos , Animais , Colesterol/sangue , Colesterol/metabolismo , Inibidores Enzimáticos/uso terapêutico , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Obesidade/etiologia , Obesidade/metabolismo , Fatores de Tempo , Triglicerídeos/metabolismo
2.
Chem Pharm Bull (Tokyo) ; 58(5): 673-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20460795

RESUMO

In a program to discover new small molecule diacylglycerol acyltransferase (DGAT)-1 inhibitors, screening of our in-house chemical library was carried out using recombinant human DGAT-1 enzyme. From this library, the lead compound 1a was identified as a new class of DGAT-1 inhibitor. A series of novel N-(substituted heteroaryl)-4-(substituted phenyl)-4-oxobutanamides 2 was designed from 1a, synthesized and evaluated for inhibitory activity against DGAT-1 enzyme. Among these compounds, N-(5-benzyl-4-phenyl-1,3-thiazol-2-yl)-4-(4,5-diethoxy-2-methylphenyl)-4-oxobutanamide 9 was found to exhibit potent inhibitory activity and good enzyme selectivities. Following administration in KKA(y) mice with 3 mg/kg high fat diet admixture for four weeks, 9 reduced body weight gain and white adipose tissue weight without affecting total food intake. These results suggested that the small molecule DGAT-1 inhibitor might have potential in the treatment of obesity and metabolic syndrome.


Assuntos
Amidas/síntese química , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Amidas/química , Amidas/farmacologia , Animais , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Bibliotecas de Moléculas Pequenas
3.
J Ethnopharmacol ; 116(1): 96-101, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18093770

RESUMO

INTRODUCTION: Mirabilis jalapa Linn is a well-studied plant. The indigenous people of Mexico use Mirabilis jalapa to cure many infirmities including dysentery, diarrhea, muscular pain and abdominal colic. In the present investigation, we have further characterized some pharmacological properties of an extract of Mirabilis jalapa flowers; therefore, we intend to contribute to understand the pharmacological effects and clarify the complex use of this medicinal plant. RESULTS: The extract of Mirabilis jalapa (1-1000 mug/mL) exhibits an inhibitory effect (IC(50)=18+/-0.7 micorg/mL) on gut smooth muscle contractility whereas it stimulates the contraction of rabbit aortic muscle (EC(50)=11.60+/-0.26 micorg/mL) in a concentration-dependent manner. CONCLUSIONS: These effects were not due to either ACh or HIS receptors blockage, IP(3), cAMP, cGMP, Ca(2+) release from intracellular storage, or protein kinase mediated contraction-relaxation mechanisms. The effects inducted by the Mirabilis jalapa extract may involve a serotoninergic mechanism, which, in turn, interacts with other adrenergic systems. Further studies are necessary to identify the active compounds within the extract and to elucidate the mechanism of action.


Assuntos
Mirabilis , Parassimpatolíticos/farmacologia , Extratos Vegetais/farmacologia , Animais , Relação Dose-Resposta a Droga , Flores , Cobaias , Técnicas In Vitro , Masculino , Coelhos , Receptores de Serotonina/fisiologia
4.
J Radiat Res ; 47(3-4): 295-303, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16988493

RESUMO

Medaka (Oryzias latipes) embryos at 25-26 and 28-30 stages were irradiated with a single acute dose of 10 Gy of X-ray, which is lower than the LD(50 )of the embryos. The effects on developing brains were examined under a stereomicroscope in living embryos until hatching. All the irradiated embryos survived; however, from 6 to 35 h after X-ray irradiation, massive clusters of optically opaque and round cells were observed either in the entire brain region (when irradiated at 25-26 stages) or mainly in the optic tectum (when irradiated at 28-30 stages). Histological examination and TUNEL showed that these cells are clusters of dead cells. These dead cell clusters disappeared thereafter, and the irradiated embryos continued to develop apparently normally. The grown irradiated embryos, however, had smaller brains and eyes than the nonirradiated control embryos. At hatching, the irradiated embryos exhibited histological abnormalities in the brain, particularly in the torus longitudinalis, and in the retina, although most of them hatched normally and survived. The results indicate that brain cell death and a reduced brain size can be observed in living irradiated embryos, and suggest that the medaka embryo is useful for screening the developmental neurotoxicity effects of various hazardous factors.


Assuntos
Apoptose/efeitos da radiação , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/efeitos da radiação , Oryzias/anatomia & histologia , Oryzias/embriologia , Animais , Neurônios/citologia , Neurônios/efeitos da radiação , Doses de Radiação
5.
Biol Pharm Bull ; 29(6): 1186-90, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16755014

RESUMO

The antispasmodic activity of extracts from the aerial parts of Buddleja scordioides and Buddleja perfoliata (family: Scrophulariaceae) was studied on isolated tissue preparations from rabbit and guinea pig intestine. The chloroformic extract from the plants exhibited a significant relaxation on the spontaneous contraction of isolated rabbit jejunum at concentrations ranging from 1 to 400 microg/ml, and also caused an inhibitory effect on both K+ and Ca2+ induced contractions in the same tissue. The extracts at moderate doses (50 microg/ml) reduced 5-hydroxytryptamine (5-HT), acetylcholine and histamine induced contractions on isolated guinea pig ileum. Therefore, B. scordioides and B. perfoliata possess similar relaxant mechanism of action, in view of the fact that both inhibit K+ induce contraction and act through serotoninic, muscarinic and histaminic receptors. So, these data support the idea that the extracts may interfere either with calcium mobilization from intracellular stores, or with calcium interaction with regulatory proteins (e.g., calmodulin), or in other steps in the calcium signaling pathway. This leads us to suggest that the spasmolytic effect of both Buddleja species on smooth muscular contractility are due to the same or similar compounds occurring in these two species, which might be present in similar quantities.


Assuntos
Buddleja/química , Intestino Delgado/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Extratos Vegetais/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Cobaias , Íleo/efeitos dos fármacos , Técnicas In Vitro , Jejuno/efeitos dos fármacos , Masculino , Medicina Tradicional , México , Músculo Liso/efeitos dos fármacos , Parassimpatolíticos/isolamento & purificação , Componentes Aéreos da Planta/química , Extratos Vegetais/isolamento & purificação , Coelhos
6.
Rinsho Shinkeigaku ; 43(6): 335-40, 2003 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-14503352

RESUMO

A 70-year-old, right-handed man was admitted to our hospital for his sudden-onset topographical disorientation. He failed to find his way to familiar places, but he knew distance and direction to the places. Neurological examination revealed homonymous left-upper quadrantanopsia on Goldmann perimeter and hypoesthesia over the left side of his body. Magnetic resonance imaging showed an abnormal intensity area at the right medial temporo-occipital region, due to the infarct of the right posterior cerebral arterial territory. The neuropsychological examination revealed agnosia for streets, and prosopagnosia without any other disturbance of visual perception. Both visual and topographical memories were intact. It is suggested that, in this case, the agnosia for streets was caused by impairment of recognizing familiar streets and houses or disconnection between their recognition and memory.


Assuntos
Agnosia/etiologia , Infarto Cerebral/complicações , Orientação/fisiologia , Idoso , Agnosia/psicologia , Confusão/etiologia , Confusão/psicologia , Humanos , Masculino , Transtornos da Memória , Percepção Visual
7.
Acta Neuropathol ; 106(5): 436-40, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12898155

RESUMO

Apolipoprotein E (ApoE) in neurons is suggested to play crucial roles in neuronal degeneration and regeneration. We used antibodies against ApoE and phosphorylated neurofilament (pNF) to investigate the immunohistochemical features of ballooned neurons (BNs) in infarction and in various chronic degenerative disorders, including Pick body disease, corticobasal degeneration/progressive supranuclear palsy, Alzheimer's disease, and frontotemporal dementia. BNs in these chronic degenerative processes were intensely labeled with the anti-pNF as reported, whereas BNs in infarction showed less intense pNF-like immunoreactivity (IR). In addition, BNs in infarction were characterized by an intense ApoE-like IR. This ApoE-like IR was inconsistent or less intense in BNs in the chronic degenerative processes. The rarity of ApoE-positive glial cells in the vicinity of ApoE-positive BNs suggests that accumulated ApoE in BNs is generated in the neurons. Accumulation of ApoE in BNs in infarction may be linked to a regenerative process after acute transection of axons, which seems compromised in chronic degenerative processes.


Assuntos
Apolipoproteínas E/metabolismo , Infarto/metabolismo , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica/métodos , Infarto/patologia , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/patologia , Proteínas de Neurofilamentos/metabolismo , Neurônios/patologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia
8.
J Am Chem Soc ; 125(16): 4688-9, 2003 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-12696869

RESUMO

Treatment of an (allyl)organosilane with silica gel in refluxing toluene brought about deallylation forming an Si-O-Si bond with the silicon on the silica gel. This Si-O-Si bond formation provides us with a new reliable method for the functionalization of a silica gel surface.

9.
Acta Neuropathol ; 106(2): 121-4, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12715185

RESUMO

A series of human brains with cerebral infarction obtained at autopsy were investigated to clarify the possible contribution of aquaporin 4 (AQP4) to the development of brain edema. Cellular localization of AQP4 and its relation to ischemic foci were examined with double-labeling immunohistochemistry. AQP4 immunoreactivity (IR) was more intense at the periphery of ischemic foci than at their center. Double-labeling study demonstrated that AQP4 IR was restricted to astrocytes and was localized to their entire processes, including their end feet facing the outer surface of capillaries. Moreover, AQP4 IR, detectable in the subpial and subependymal zone in the normal condition, was more intense in the vicinity of ischemic foci. Accumulation of AQP4 IR may reflect its participation in the development of brain edema in human brains by playing a role in the transport of water not only through blood vessel walls but also through pial and ependymal surface of the brain.


Assuntos
Aquaporinas/metabolismo , Encéfalo/metabolismo , Infarto Cerebral/metabolismo , Idoso , Idoso de 80 Anos ou mais , Aquaporina 4 , Astrócitos/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Infarto Cerebral/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Distribuição Tecidual
10.
Stroke ; 34(4): 875-80, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12649507

RESUMO

BACKGROUND AND PURPOSE: Cellular origin of apolipoprotein E (ApoE) in the human brain and its roles in physiological and pathological conditions remain to be clarified. METHODS: Immunolocalization of ApoE was investigated in a series of autopsied human brains with or without infarction. ApoE expression was also estimated on immunoblot on protein extracts from autopsied brains and a cultured neuroblastoma cell line of human origin (GOTO) subjected to an oxidative stress induced by exposure to hydrogen peroxide (0.2 mmol/L). RESULTS: In addition to astrocytes and microglia, neurons and degenerated axons in and around the ischemic foci contained ApoE-like immunoreactivity, which was more intense in recent ischemic foci. Immunoblot demonstrated an increase in expression of ApoE in brain extracts from ischemic lesion, and this increase was also pronounced in the cultured neuroblastoma cell line after the stress. CONCLUSIONS: Accumulation of ApoE in neurons in and around ischemic foci of the human brain is related to an increase in ApoE synthesis in neurons, as seen in cultured neuronal cells after oxidative stress. Intrinsic regenerative activity of neuron in reaction to external insults may be related to this increase in ApoE of neuronal origin.


Assuntos
Apolipoproteínas E/biossíntese , Encéfalo/metabolismo , Infarto Cerebral/metabolismo , Neurônios/metabolismo , Idoso , Apolipoproteínas E/análise , Apolipoproteínas E/imunologia , Western Blotting , Encéfalo/citologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Células Tumorais Cultivadas
11.
Shokuhin Eiseigaku Zasshi ; 43(3): 165-8, 2002 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-12238155

RESUMO

A simple and convenient method for colorimetric determination of sulfite in foods based on its conversion to formaldehyde with sulfite oxidase and catalase was developed. Sulfite in a sample was extracted with water and then diluted with methanol. One mL of sample solution containing about 5-10 micrograms of sulfite was taken into a test tube with a ground-glass stopper, and 3 mL of 0.04 mol/L borate buffer (pH 8.7), 1 mL of 0.4% 3-methyl-2-benzothiazolinone hydrazone (MBTH) solution, 2,000 units of catalase solution and 1.0 units of sulfite oxidase were added. The mixture was incubated for 35 minutes at 37 degrees C. Then 0.15 mL of 1 mol/L hydrochloric acid and 5 mL of 0.2% iron(III) nitrate solution were added. The reaction mixture was transferred to a measuring flask after standing for 5 minutes at room temperature, and diluted to 20 mL with methanol. The absorbance of this solution was measured using a spectrophotometer at the wavelength of 635 nm. The calibration curve prepared with sodium sulfite showed linearity between 0 to 16 micrograms/mL as sulfur dioxide. The recoveries of sulfite in "Kanpyo" (dried gourd shavings) and "Konnyaku-seiko" (devil's-tongue fine powder) by the proposed method were 97-104%, and the coefficients of variation were below 6%. The sulfite values in these foods determined by the proposed method were reasonably consistent with those obtained by the bubbling distillation-alkaline titration method.


Assuntos
Catalase/farmacologia , Colorimetria/métodos , Análise de Alimentos/métodos , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/farmacologia , Sulfitos/análise , Aprotinina , Concentração de Íons de Hidrogênio
12.
Shokuhin Eiseigaku Zasshi ; 43(1): 44-8, 2002 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-11998319

RESUMO

A simple and rapid method for spore rec-assay by utilizing dry sheet medium culture (Compactdry TC, CTC) for determining numbers of bacteria, instead of the spore agar plate, was developed. One mL of spore suspension (2 x 10(6)/mL) of Bacillus subtilis strain M45 Rec- or H17 Rec+ was inoculated in the center of the CTC plate. In the case of metabolic activation, 1 mL of mixed solution (spore suspension of M45 or H17: 9,000 x g supernatant of rat-liver homogenate treated with Aroclor 1254 = 19:1) was used. The spore suspension spreads over the whole sheet in seconds and gels. A paper disk impregnated with 20-40 microL of the sample solution and 20 microL of the cofactor solution was placed on the surface of CTC plate. For the assay of samples that do not require metabolic activation, use of the cofactor solution can be omitted. After 48 hr incubation at 37 degrees C, 0.01% MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide] aqueous solution (0.5 mL) was dropped uniformly on the plate. The plate was left for 5 min, and the diameter of the inhibition circle was measured with slide calipers. The samples for which the difference in inhibition zone between M45 and H17 was more than 2 mm were judged positive. Under these conditions, the DNA damaging activities of sodium sulfite, sodium benzoate and citric acid, used as food additives, were investigated by the proposed method. Sodium sulfite and sodium benzoate gave positive results and citric acid gave a negative result with or without metabolic activation, in agreement with the results obtained by the conventional method.


Assuntos
Técnicas Bacteriológicas/métodos , Ágar , Bacillus subtilis/citologia , Contagem de Células , Ácido Cítrico/farmacologia , DNA Bacteriano/efeitos dos fármacos , Aditivos Alimentares/farmacologia , Benzoato de Sódio/farmacologia , Esporos Bacterianos , Sulfitos/farmacologia
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