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1.
Curr Issues Mol Biol ; 45(10): 8427-8443, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37886974

RESUMO

Focal cerebral ischemia (fCI) can result in brain injury and sensorimotor deficits. Brown algae are currently garnering scientific attention as potential therapeutic candidates for fCI. This study investigated the therapeutic effects of the hot water extract of Petalonia binghamiae (wPB), a brown alga, in in vitro and in vivo models of fCI. The neuroprotective efficacy of wPB was evaluated in an in vitro excitotoxicity model established using HT-22 cells challenged with glutamate. Afterward, C57/BL6 mice were administered wPB for 7 days (10 or 100 mg/kg, intragastric) and subjected to middle cerebral artery occlusion and reperfusion (MCAO/R) operation, which was used as an in vivo fCI model. wPB co-incubation significantly inhibited cell death, oxidative stress, and apoptosis, as well as stimulated the expression of heme oxygenase-1 (HO-1), an antioxidant enzyme, and the nuclear translocation of its upstream regulator, nuclear factor erythroid 2-related factor 2 (Nrf2) in HT-22 cells challenged with glutamate-induced excitotoxicity. Pretreatment with either dose of wPB significantly attenuated infarction volume, neuronal death, and sensorimotor deficits in an in vivo fCI model. Furthermore, the attenuation of oxidative stress and apoptosis in the ischemic lesion accompanied the wPB-associated protection. This study suggests that wPB can counteract fCI via an antioxidative effect, upregulating the Nrf2/HO-1 pathway.

2.
Nutrients ; 13(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34684537

RESUMO

Anti-inflammatory agents that are safer and more effective than the currently used non-steroidal anti-inflammatory drugs are urgently needed. The dicaffeoylquinic acid (diCQA) isomer 4,5-diCQA exhibits antioxidant activity and various other health-promoting benefits; however, its anti-inflammatory properties require further investigation. This study was conducted to evaluate the anti-inflammatory properties of 4,5-diCQA in vitro and in vivo using RAW264.7 cells and a carrageenan-induced inflammation model, respectively. In RAW264.7 cells, 4,5-diCQA pretreatment significantly inhibited lipopolysaccharide-induced expression of nitric oxide, prostaglandin E2, nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α, interleukin-1ß, and interleukin-6, without inducing cytotoxicity. The inhibitory effects of 4,5-diCQA were mediated by the suppression of nuclear factor-κB nuclear translocation and mitogen-activated protein kinase (MAPK) phosphorylation. Oral administration of 4,5-diCQA at doses of 5, 10, and 20 mg/kg of the body weight suppressed carrageenan-induced edema and the expression of nitric oxide synthase, cyclooxygenase-2, and tumor necrosis factor-α in a dose-dependent manner. Collectively, our results suggest that 4,5-diCQA exerts anti-inflammatory effects by suppressing activation of the nuclear factor-κB and MAPK pathways in vitro and reducing carrageenan-induced edema in vivo. Therefore, 4,5-diCQA shows potential as a natural alternative to non-steroidal anti-inflammatory drugs.


Assuntos
Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Ácido Quínico/análogos & derivados , Animais , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Dinoprostona/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/metabolismo , Fosforilação/efeitos dos fármacos , Ácido Quínico/química , Ácido Quínico/farmacologia , Ácido Quínico/uso terapêutico , Células RAW 264.7 , Ratos Sprague-Dawley
3.
Foods ; 10(9)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34574235

RESUMO

In the present study, the properties of the Lactiplantibacillus (Lpb.) plantarum WiKim0112 isolated from kimchi were evaluated by comparing its probiotic properties to those of Lpb. plantarum WCFS1 and KACC 11451 isolated from different sources. In both pH 2 and 3, media containing pepsin, Wikim0112, and WCFS1 showed higher cell viability than KACC11451. Viability of all Lpb. plantarum strains in a medium containing pancreatin and bile salt oxgall was significantly decreased compared to the control. WCFS1 showed the highest thermotolerance, followed by Wikim0112 and KACC11451. Wikim0112 showed a similar level of antibacterial activity to WCFS1 and exhibited an overall higher antibacterial activity than KACC11451 against six pathogens. All Lpb. plantatum strains showed high antioxidant activities in SOD, DPPH, and ABTS assays, especially Wikim0112 and WCFS1 exhibited a higher antioxidant activity than KACC11451. All Lpb. plantarum strains showed approximately 60-62% adhesion rates to Caco-2 cells. Moreover, in LPS-stimulated Caco-2 cells, all Lpb. plantarum strains significantly decreased the mRNA expression of pro-inflammatory cytokines (i.e., IL-1ß, IL-6, and TNF-α); Wikim0112 significantly increased the mRNA expression of IL-4 and IFN-γ. Wikim0112 was resistant to streptomycin and vancomycin, whereas WCFS1 and KACC11451 were resistant to four (clindamycin, ciprofloxacin, tetracycline, and vancomycin) and three (ciprofloxacin, tetracycline, and vancomycin) antibiotics, respectively. These results, taken together, indicated that compared to Lpb. plantarum strains isolated from different sources, Wikim0112 showed desirable probiotic properties, suggesting its potential applications in the food and pharmaceutical industries.

4.
Neuroreport ; 30(17): 1222-1229, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31651708

RESUMO

Fusidic acid, a steroidal antibiotic, possesses antimicrobial, antioxidant, and anti-inflammatory properties, but the effect of fusidic acid against neurodegenerative disease-related cell death has not been studied. Here, we investigated the protective effects of fusidic acid on sodium nitroprusside (SNP)-induced toxicity in C6 glial cells. Fusidic acid (5-20 µM) prevented SNP (100 µM)-induced cell death dose dependently, and effectively attenuated SNP-induced generation of nitric oxide (NO), total reactive oxygen species (ROS), and peroxynitrite (ONOO). Fusidic acid (20 µM) pretreatment significantly suppressed SNP (100 µM)-induced apoptotic events, such as nuclear condensation and caspase-3 activation. In addition, fusidic acid effectively attenuated SNP-induced endoplasmic reticulum (ER) stress markers, such as GRP78, IRE1, ATF6, PERK, XBP1s, eIF2α, CHOP, and caspase-12. A specific adenosine monophosphate-activated protein kinase (AMPK) inhibitor, compound C (10 µM), reversed the preventive effects of fusidic acid against SNP-induced cytotoxicity, CHOP elevation, and caspase-3 activation. These results suggest that fusidic acid can protect C6 glial cells against cytotoxicity, through the regulation of AMPK pathway and apoptotic events.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Fusídico/farmacologia , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Antibacterianos/farmacologia , Linhagem Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Nitroprussiato/toxicidade , Ratos
5.
Biol Pharm Bull ; 42(1): 94-102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30606992

RESUMO

Glutamate-mediated cytotoxicity has been implicated in the pathogenesis of neurological diseases, including Parkinson's disease, Alzheimer's disease, and stroke. In this study, we investigated the protective effects of alpha-lipoic acid (ALA), a naturally occurring thiol antioxidant, on glutamate-induced cytotoxicity in cultured C6 astroglial cells. Exposure to high-dose glutamate (10 mM) caused oxidative stress and mitochondrial dysfunction through the elevation of reactive oxygen species, depletion of glutathione, and loss of the mitochondrial membrane potential (ΔΨm). Pretreatment with ALA (200 µM), however, significantly inhibited the glutamate-induced oxidative stress and mitochondrial dysfunction. ALA pretreatment dose-dependently suppressed glutamate-induced apoptotic events including altered nuclear morphology and activation of caspase-3. In addition, ALA significantly attenuated glutamate-induced endoplasmic reticulum (ER) stress markers; namely, glucose-regulated protein 78 (GRP78), activating transcription factor 6 (ATF6), protein kinase regulated by RNA (PKR)-like ER-associated kinase (PERK), eukaryotic translation initiation factor 2 alpha (eIF2α), inositol-requiring enzyme 1 (IRE1), CCAAT/enhancer binding protein homologous protein (CHOP), and caspase-12. We confirmed that CHOP and caspase-12 are key mediators of glutamate-induced ER stress. Furthermore, exposure of the cells to a caspase-12-specific inhibitor and CHOP small interfering RNAs (siRNAs) led to restoration of the ΔΨm that was damaged by glutamate treatment. These results suggest that ALA can effectively suppress oxidative stress, mitochondrial dysfunction, and ER stress in astroglial cells.


Assuntos
Citoproteção/efeitos dos fármacos , Citotoxinas/toxicidade , Glioma/metabolismo , Ácido Glutâmico/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Ácido Tióctico/farmacologia , Animais , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Citoproteção/fisiologia , Relação Dose-Resposta a Droga , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Espécies Reativas de Oxigênio/metabolismo
6.
Implant Dent ; 24(1): 101-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25621556

RESUMO

PURPOSE: The purpose of this study was to evaluate the ability of new bone formation of deproteinized bovine bone (Bio-Oss) and mineralized allogenic bone (Tutoplast). MATERIALS AND METHODS: Sixty rats were divided into control and experimental groups (groups 1 and 2): control group, unfilled control; group 1, Bio-Oss; group 2, Tutoplast, respectively. The animals were killed after 6 and 12 weeks, and newly formed bone was analyzed histomorphometrically. RESULTS: In the control group, some new bone formed in the rim of the defect area. In the group 1, newly formed bone was thinner than the adjacent normal bone, and Bio-Oss particles were observed. In the group 2, showed a pattern of gradual fusion with adjacent bone, as well as particles in some areas, similar to the Bio-Oss-treated group. In the 12-week groups, the amount of new bone formation was significantly higher in the experimental groups than in the control group, and it was significantly higher in group 2 than in group 1. CONCLUSION: Although Tutoplast and Bio-Oss graft materials seem to be useful for bone grafts, Tutoplast showed more active new bone formation than Bio-Oss.


Assuntos
Substitutos Ósseos , Transplante Ósseo , Minerais , Osteogênese , Politetrafluoretileno , Animais , Transplante Ósseo/métodos , Bovinos , Masculino , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley
7.
Oral Surg Oral Med Oral Pathol Oral Radiol ; 114(5 Suppl): S126-31, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23063388

RESUMO

OBJECTIVE: The purpose of this study was to evaluate bone formation after using allogeneic bone alone or with a membrane. STUDY DESIGN: Bone graft was performed using the allograft Tutoplast, mineralized cancellous bone allograft, and pericardium in calvarial defects of 60 rats. Rats were divided in 3 groups: control group (no bone graft), group 1 (bone graft without membrane), and group 2 (bone graft with membrane). RESULTS: The most new bone formation occurred in group 2. After 6 weeks, group 2 showed infiltration of inflammatory cells, and inflammatory cells were still observed after 12 weeks. The membrane remained even after 12 weeks, and the membrane facilitated bone regeneration by blocking connective tissue. CONCLUSIONS: The membrane facilitated new bone formation by inhibiting connective tissue invasion.


Assuntos
Implantes Absorvíveis , Regeneração Óssea/fisiologia , Transplante Ósseo/métodos , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Análise de Variância , Animais , Materiais Biocompatíveis , Transplante Ósseo/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Crânio/cirurgia , Transplante Homólogo/métodos
8.
Biotechnol Lett ; 34(4): 779-87, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22160329

RESUMO

A novel barrier membrane composed of poly(lactic-co-glycolic acid) particles loaded with dexamethasone (DEX) as a bioactive molecule was produced via a modified nanoprecipitation method without any mixing. The particle membranes had a bilayer structure: one side was smooth and had a compact surface that was connected to larger particles, while the opposite side was rough, porous and connected to smaller particles. Additionally, a cross-section of the particle membrane had a porous structure with nano and micro sized irregular pores. Process optimization revealed that NaCl concentration in the water phase, with acetone as solvent and water as a non-solvent, played critical roles in determining the properties of the particle membranes, such as DEX encapsulation efficiency, thickness and surface morphologies of the particle membranes. A novel barrier membrane containing DEX using polymer particle drug capture technology has been successfully developed.


Assuntos
Anti-Inflamatórios/administração & dosagem , Regeneração Óssea/efeitos dos fármacos , Dexametasona/administração & dosagem , Portadores de Fármacos/administração & dosagem , Ácido Láctico/administração & dosagem , Nanopartículas , Ácido Poliglicólico/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ácido Láctico/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
9.
J Agric Food Chem ; 58(3): 1543-50, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20073473

RESUMO

Carnosol, a naturally occurring bioactive phenolic diterpene originating from rosemary and sage, has been shown to exert antioxidant and anti-inflammatory effects. This study examined possible protective effects of carnosol on sodium nitroprusside (SNP)-induced cytotoxicity in C6 glial cells. Carnosol (1-10 microM) dose-dependently attenuated SNP (100 microM)-induced cell death and NO production. SNP-induced apoptotic characteristics, including DNA fragmentation, caspase-3 activation, and c-jun N-terminal protein kinase (JNK) phosphorylation, were significantly suppressed by carnosol (10 microM). In addition, carnosol pretreatment restored the level of reduced glutathione (GSH), which was diminished by SNP treatment. Although both SNP (100 microM) and carnosol (10 microM) stimulated the HO-1 expression time-dependently, SNP caused a temporal increase in HO-1 in early time periods (3-6 h) before cell death occurred. In contrast, carnosol induced the sustained expression of HO-1 until a late time point (24 h). The addition of 1 microM zinc protoporphyrin IX (ZnPP), a specific HO inhibitor, with SNP or carnosol further reduced cell viability. Also, the addition of ZnPP inhibited the protective effect of carnosol against SNP-induced cytotoxicity in C6 cells. These results suggest that carnosol possesses abilities to inhibit SNP-mediated glial cell death through modulation of apoptotic events and induction of HO-1 expression.


Assuntos
Abietanos/farmacologia , Neuroglia/citologia , Nitroprussiato/toxicidade , Extratos Vegetais/farmacologia , Rosmarinus/química , Salvia officinalis/química , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ratos
10.
Neuroreport ; 19(13): 1301-4, 2008 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-18695511

RESUMO

Carnosic acid (CA) is one of the bioactive polyphenols present in extracts of the herb rosemary (Rosmarinus officinalis). In this study, we examined possible protective effects of CA on neurotoxicity induced by dieldrin, an organochlorine pesticide implicated in sporadic Parkinson's disease, in cultured dopaminergic cells (SN4741). CA (5-10 muM) pretreatment showed potent protective effects in a concentration-related manner and prevented dieldrin (10 muM)-induced caspase-3 activation, Jun N-terminal kinase phosphorylation, and caspase-12 activation. Furthermore, dieldrin-induced downregulation of brain-derived neurotrophic factor production was significantly attenuated by CA. These results suggest that CA may safeguard dopaminergic neuronal cells from environmental neurotoxins by enhancing brain-derived neurotrophic factor and repressing apoptotic molecules.


Assuntos
Abietanos/farmacologia , Apoptose/efeitos dos fármacos , Dieldrin/toxicidade , Dopamina/metabolismo , Neurônios/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Antioxidantes/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Caspase 12/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Rosmarinus/química
11.
Toxicology ; 250(2-3): 109-15, 2008 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-18644421

RESUMO

In this study, we investigated the protective effects of rosmarinic acid (RA) on H(2)O(2)-induced neurotoxicity in human dopaminergic cell line, SH-SY5Y. Results showed that RA significantly attenuated H(2)O(2)-induced reactive oxygen species (ROS) generation and apoptotic cell death. Rosmarinic acid effectively suppressed the up-regulation of Bax and down-regulation of Bcl-2. Furthermore, RA stimulated the antioxidant enzyme heme oxygenase-1 (HO-1). We also demonstrated that the HO-1 induction by RA was associated with the protein kinase A (PKA) and phosphatidylinositiol-3-kinase (PI3K) signaling pathways. These results suggest that RA can protect SH-SY5Y cells under oxidative stress conditions by regulating apoptotic process. Thus, RA should be clinically evaluated for the prevention of neurodegenerative diseases.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cinamatos/farmacologia , Depsídeos/farmacologia , Dopamina/fisiologia , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/toxicidade , Neurônios/fisiologia , Oxidantes/toxicidade , Western Blotting , Caspase 3/metabolismo , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Expressão Gênica/efeitos dos fármacos , Genes bcl-2/efeitos dos fármacos , Heme Oxigenase-1/biossíntese , Humanos , Neurônios/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/biossíntese , Proteína X Associada a bcl-2/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ácido Rosmarínico
12.
Mycol Res ; 112(Pt 8): 990-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18550350

RESUMO

In this study we purified and characterized a fibrinolytic protease from the mycelia of Perenniporia fraxinea. The apparent molecular mass of the purified enzyme was estimated to be 42kDa by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), fibrin zymography and size exclusion using fast protein liquid chromatography (FPLC). The first 20 amino acid residues of the N-terminal sequence were ASYRVLPITKELLPPEFFVA, which shows a high degree of similarity with a fungalysin metallopeptidase from Coprinopsis cinerea. The optimal reaction pH value and temperature were pH 6.0 and 35-40 degrees C, respectively. Results for the fibrinolysis pattern showed that the protease rapidly hydrolyzed the fibrin alpha-chain followed by the beta-chain. The gamma-gamma chains were also hydrolyzed, but more slowly. The purified protease effectively hydrolyzed fibrinogen, preferentially digesting the Aalpha-chains of fibrinogen, followed by Bbeta- and gamma-chains. We found that protease activity was inhibited by Cu(2+), Fe(3+), and Zn(2+), but enhanced by the additions of Mn(2+), Mg(2+) and Ca(2+) metal ions. Furthermore, the protease activity was inhibited by EDTA, and it was found to exhibit a higher specificity for the chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The mycelia of P. fraxinea may thus represent a source of new therapeutic agents to treat thrombosis.


Assuntos
Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Metaloproteases/química , Metaloproteases/isolamento & purificação , Polyporales/enzimologia , Sequência de Aminoácidos , Estabilidade Enzimática , Fibrinolíticos/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Metaloproteases/metabolismo , Dados de Sequência Molecular , Peso Molecular , Micélio/química , Micélio/enzimologia , Micélio/genética , Polyporales/química , Polyporales/genética , Alinhamento de Sequência , Especificidade por Substrato , Madeira/microbiologia
13.
J Microbiol Biotechnol ; 17(8): 1271-83, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18051595

RESUMO

A fibrinolytic protease (PoFE) was purified from the cultured mycelia of the edible oyster mushroom Pleurotus ostreatus, using a combination of various chromatographies. The purification protocol resulted in an 876-fold purification of the enzyme, with a final yield of 6.5%. The apparent molecular mass of the purified enzyme was estimated to be 32 kDa by SDS-PAGE, fibrin-zymography, and size exclusion using FPLC. The optimal reaction pH value and temperature were pH 6.5 and 35 degrees C, respectively. PoFE effectively hydrolyzed fibrinogen, preferentially digesting the A alpha-chain and the B beta-chain over the gamma-chain. Enzyme activity was enhanced by the addition of Ca2+, Zn2+, and Mg2+ ions. Furthermore, PoFE activity was potently inhibited by EDTA, and it was found to exhibit a higher specificity for the chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The first 19 amino acid residues of the N-terminal sequence were ALRKGGAAALNIYSVGFTS, which is extremely similar to the metalloprotease purified from the fruiting body of P. ostreatus. In addition, we cloned the PoFE protein, encoding gene, and its nucleotide sequence was determined. The cDNA of cloned PoFE is 867 nucleotides long and consists of an open reading frame encoding 288 amino acid residues. Its cDNA showed a high degree of homology with PoMEP from P. ostreatus fruiting body. The mycelia of P. ostreatus may thus represent a potential source of new therapeutic agents to treat thrombosis.


Assuntos
Fibrina/metabolismo , Metaloproteases/isolamento & purificação , Metaloproteases/metabolismo , Micélio/enzimologia , Pleurotus/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Sequência de Bases , Cátions Bivalentes/farmacologia , Cromatografia em Gel , Clonagem Molecular , Coenzimas/farmacologia , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Metaloproteases/química , Metaloproteases/genética , Metais/farmacologia , Dados de Sequência Molecular , Peso Molecular , Oligopeptídeos/metabolismo , Fases de Leitura Aberta , Pleurotus/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Temperatura
14.
Int J Dev Neurosci ; 25(8): 491-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17976945

RESUMO

Typical autosomal recessive juvenile Parkinsonism (AR-JP) is resulted from the loss of function mutation in the parkin gene. In an effort to learn more about the cell type-specific functional role of parkin, we used in vitro model such as locus coeruleus (LC) noradrenergic (NA) neuronal progenitor cell line, LC3541. Employing this in vitro model, we revealed that parkin plays a crucial role in phenotypic differentiation of NA neurons. Our results showed that parkin mRNA was expressed during the differentiation of NA neuronal progenitor cell line and that the level of the parkin mRNA was down-regulated by oxidative stress in the NA neuronal cells. Parkin protein overexpression in LC3541 cells induced expression of NA markers (TH, phox2a and DBH). Small interfering RNA (SiRNA) for parkin supressed NA differentiation and DBH expression. Preventing protein kinase A (PKA) activation with PKI attenuated expression of DBH in parkin overexpressed LC3541 cells. These findings suggest that the relative abundance of parkin enhances differentiation of NA phenotypes via a PKA-dependent pathway.


Assuntos
Expressão Gênica/fisiologia , Neurônios/fisiologia , Norepinefrina/fisiologia , Sistema Nervoso Simpático/fisiologia , Ubiquitina-Proteína Ligases/genética , Animais , Western Blotting , Diferenciação Celular/fisiologia , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dopamina beta-Hidroxilase/genética , Dopamina beta-Hidroxilase/metabolismo , Humanos , Imuno-Histoquímica , Hibridização In Situ , Locus Cerúleo/citologia , Locus Cerúleo/metabolismo , Camundongos , Estresse Oxidativo/fisiologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
15.
Biosci Biotechnol Biochem ; 71(9): 2214-22, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17827681

RESUMO

In this study we purified a fibrinolytic enzyme from the culture supernatant of Flammulina velutipes mycelia by ion exchange and gel filtration chromatographies, it was designated as F. velutipes protease (FVP-I). This purification protocol resulted in 18.52-fold purification of the enzyme at a final yield of 0.69%. The molecular mass of the purified enzyme was estimated to be 37 kDa by SDS-PAGE, fibrin-zymography and size exclusion by FPLC. This protease effectively hydrolyzed fibrin, preferentially digesting alpha-chain over beta-and gamma-gamma chain. Optimal protease activity was found to occur at a pH of 6.0 and a temperature of 20 to 30 degrees C. The protease activity was inhibited by Cu2+, Fe2+ and Fe3+ ions, but was found to be enhanced by Mn2+ and Mg2+ ions. Furthermore, FVP-I activity was potently inhibited by EDTA and EGTA, and it was found to exhibit a higher specificity for chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The first 20 amino acid residues of the N-terminal sequence of FVP-I were LTYRVIPITKQAVTEGTELL. They had a high degree of homology with hypothetical protein CC1G_11771, GeneBank Accession no. EAU86463.


Assuntos
Agaricales/enzimologia , Endopeptidases/isolamento & purificação , Endopeptidases/metabolismo , Fibrinólise , Sequência de Aminoácidos , Cromatografia em Gel , Endopeptidases/química , Ativação Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Metais/farmacologia , Dados de Sequência Molecular , Peso Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura
16.
J Microbiol ; 44(6): 622-31, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17205040

RESUMO

In this study we purified a fibrinolytic enzyme from Cordyceps militaris using a combination of ion-exchange chromatography on a DEAE Sephadex A-50 column, gel filtration chromatography on a Sephadex G-75 column, and FPLC on a HiLoad 16/60 Superdex 75 column. This purification protocol resulted in a 191.8-fold purification of the enzyme and a final yield of 12.9 %. The molecular mass of the purified enzyme was estimated to be 52 kDa by SDS-PAGE, fibrin-zymography, and gel filtration chromatography. The first 19 amino acid residues of the N-terminal sequence were ALTTQSNV THGLATISLRQ, which is similar to the subtilisin-like serine protease PR1J from Metarhizium anisopliae var. anisopliase. This enzyme is a neutral protease with an optimal reaction pH and temperature of 7.4 and 37 degrees , respectively. Results for the fibrinolysis pattern showed that the enzyme rapidly hydrolyzed the fibrin alpha-chain followed by the gamma-gamma chains. It also hydrolyzed the beta-chain, but more slowly. The Aalpha, Bbeta, and gamma chains of fibrinogen were also cleaved very rapidly. We found that enzyme activity was inhibited by Cu2+ and Co2+, but enhanced by the additions of Ca2+ and Mg2+ ions. Furthermore, fibrinolytic enzyme activity was potently inhibited by PMSF and APMSF. This enzyme exhibited a high specificity for the chymotrypsin substrate S-2586 indicating it 's a chymotrypsin-like serine protease. The data we present suggest that the fibrinolytic enzyme derived from the edible and medicinal mushroom Cordyceps militaris has fibrin binding activity, which allows for the local activation of the fibrin degradation pathway.


Assuntos
Cordyceps/enzimologia , Fibrina/metabolismo , Fibrinolíticos , Carpóforos/enzimologia , Sequência de Aminoácidos , Quimotripsina , Cordyceps/crescimento & desenvolvimento , Meios de Cultura , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/metabolismo , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Serina Endopeptidases/química , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/metabolismo , Especificidade por Substrato , Temperatura
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