Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Epidemiologia (Basel) ; 5(2): 146-159, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38651387

RESUMO

BACKGROUND: The practice of self-medication (SM) is common worldwide and is an important component of medical self-care. However, improper practice can be dangerous. This study aimed to estimate the prevalence of SM and the factors associated with it among Bangladeshi adults. METHODS: A cross-sectional survey was conducted between April and June 2021 among Bangladeshi adults (aged > 19 years) using convenient sampling. A total of 1320 subjects were collected through face-to-face interviews using a standardized questionnaire. Multivariable logistic regression analysis was used to identify factors associated with the practice of SM. RESULTS: Overall, 41% of adults in our survey reported SMP. The most common illnesses that prompted SM were common cold/flu (66.4%), gastric problems (65%), and headache (64.4%). The most frequent reasons for SM were to get better-perceived quality of care (30.6%), perceiving SM without side effects (23.3%), and saving time with effectiveness (14.56%). Potential risk factors included 10 years (AOR = 1.91; 95% CI: 1.04-3.50) and >12 years of schooling (AOR = 5.03; 95% CI: 2.27-11.15), being a businessman (AOR = 4.64; 95% CI: 1.74-12.37), having ≤6 family members (AOR = 2.13; 95% CI: 1.40-3.24), being a member of a social group (AOR = 1.53; 95% CI: 1.10-2.12), a health status check after every six months (AOR = 1.52; 95% CI: 1.08-2.13), and current ill-health (AOR = 1.41; 95% CI: 1.06-1.87). Protective factors identified included ≤30 years of age (AOR = 0.40; 95% CI: 0.17-0.93), and practice of modern (AOR = 0.39; 95% CI: 0.22-0.69) and herbal (AOR = 0.45; 95% CI: 0.21-0.97) treatment modality. CONCLUSION: More than one-third of the study participants reported practicing SM. Increasing the community's awareness of the adverse outcomes of SM and not just the average experience might sway individuals away from SM, and implementing strict jurisdiction could be a way to minimize inappropriate SM.

2.
Obesity (Silver Spring) ; 24(9): 1913-21, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27430164

RESUMO

OBJECTIVE: Obesity is a chronic inflammatory disease, and adipocytes contribute to obesity-associated inflammation by releasing inflammatory mediators. High mobility group box 1 (HMGB1), a highly conserved DNA-binding protein, mainly localized to cell nuclei, has been recently recognized as an innate pro-inflammatory mediator when released extracellularly. It was hypothesized that HMGB1 is an adipocytokine that acts as an innate pro-inflammatory mediator in white adipose tissue (WAT) of patients with obesity and is associated with insulin resistance. Additionally, it was hypothesized that HMGB1 secretion is regulated by adiponectin. METHODS: 3T3-L1 cells were differentiated into mature adipocytes. After tumor necrosis factor-α (TNF-α) stimulation, HMGB1 in culture media was measured. Localizations of HMGB1 in 3T3-L1 adipocytes and human WAT were examined by immunostaining. RESULTS: HMGB1 was secreted from TNF-α-induced 3T3-L1 adipocytes through JNK signaling. HMGB1-activated MAP kinases (ERK1/2, JNK) and suppressed insulin-stimulated Akt phosphorylation in 3T3-L1 adipocytes. The cytoplasm in 3T3-L1 adipocytes and adipocytes of WAT from a patient with obesity was intensely stained with HMGB1. Adiponectin partially inhibited TNF-α-induced HMGB1 secretion from 3T3-L1 adipocytes. CONCLUSIONS: These findings suggest that HMGB1 is a pro-inflammatory adipocytokine involved in WAT inflammation and insulin resistance in patients with obesity, which may contribute to the progression of metabolic syndrome, and that adiponectin protects against HMGB1-induced adipose tissue inflammation.


Assuntos
Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Proteína HMGB1/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Obesidade/metabolismo , Células 3T3-L1/metabolismo , Adipócitos/metabolismo , Adipocinas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Camundongos , Fator de Necrose Tumoral alfa/metabolismo
3.
Pak J Biol Sci ; 15(21): 1019-26, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24163944

RESUMO

In this study, two varieties (Green and red) of water chestnuts (Trapa sp.) have been selected for their biochemical analysis as well as nutrient composition using standard methods. The proximate composition of green water chestnuts revealed moisture 62.5, ash 1.04, crude fiber 2.13%, total soluble sugar 0.92%, reducing sugar 0.33%, non-reducing sugar 0.59%, starch 8.7%, lipid 0.84%. One hundred gram of green variety contained water soluble protein 0.275 mg, beta-Carotene 60 microg, vitamin-C 1.1 mg and total phenol 0.5 mg. The minerals contents of green variety were potassium 5.22%, sodium 0.64%, calcium 0.25%, phosphorus 6.77%, sulpher 0.38%, and iron, copper, manganese and zinc 200, 430, 90 and 600 ppm, respectively. The red variety contained moisture 62.7%, ash 1.30%, crude fiber 2.27%, total soluble sugar 0.90%, reducing sugar 0.30%, non-reducing sugar 0.60%, starch 8.2%, lipid 0.83%. The red variety contained water soluble protein 0.251 mg, beta-Carotene 92 microg, vitamin-C 0.9 mg and total phenol 0.60 mg per 100 g. The red variety contained potassium 5.32%, sodium 0.59%, calcium 0.26% phosphorus 6.77%, sulpher 0.32%, Iron 200 ppm, copper 450 ppm, manganese 110 ppm and zinc 650 ppm. The free amino acids, glutamic acid, tryptophan, tyrosine, alanine, lysine and leucine were commonly found in both varieties. In addition, green and red variety contained cysteine, arginine and proline and glutamine and asparagines, respectively. Thus, the present study sheds light on the nutrient contents of the two varieties of water chestnuts and suggests that water chestnuts may play a crucial role in human nutrition.


Assuntos
Abastecimento de Alimentos , Lythraceae , Valor Nutritivo , Nozes , Humanos , Carboidratos/análise , Fibras na Dieta/análise , Lipídeos/análise , Minerais/análise , Nozes/química , Nozes/classificação , Proteínas de Plantas/análise , Vitaminas/análise , Lythraceae/química , Lythraceae/classificação
4.
Exp Ther Med ; 1(1): 109-111, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23136602

RESUMO

Estimation of the postmortem interval (PMI) is one of the most important tasks in forensic medicine. Numerous methods have been proposed for the determination of the time since death by chemical means. High mobility group box-1 (HMGB1), a nonhistone DNA-binding protein is released by eukaryotic cells upon necrosis. Postmortem serum levels of HMGB1 of 90 male Wistar rats stored at 4, 14 and 24°C since death were measured by enzyme-linked immunosorbent assay. The serum HMGB1 level showed a time-dependent increase up to seven days at 4°C. At 14°C, the HMGB1 level peaked at day 3, decreased at day 4, and then plateaued. At 24°C, the HMGB1 level peaked at day 2, decreased at day 3, and then plateaued. Our findings suggest that HMGB1 is related to the PMI in rats.

5.
Biochem Biophys Res Commun ; 390(4): 1121-5, 2009 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-19737535

RESUMO

Aquaporin-4 (AQP4) plays a role in the generation of post-ischemic edema. Pharmacological modulation of AQP4 function may thus provide a novel therapeutic strategy for the treatment of stroke, tumor-associated edema, epilepsy, traumatic brain injury, and other disorders of the central nervous system (CNS) associated with altered brain water balance. Edaravone, a free radical scavenger, is used for the treatment of acute ischemic stroke (AIS) in Japan. In this study, edaravone significantly reduced the infarct area and improved the neurological deficit scores at 24h after reperfusion in a rat transient focal ischemia model. Furthermore, edaravone markedly reduced AQP4 immunoreactivity and protein levels in the cerebral infarct area. In light of observations that edaravone specifically inhibited AQP4 in a rat transient focal ischemia model, we propose that edaravone might reduce cerebral edema through the inhibition of AQP4 expression following cerebral infarction.


Assuntos
Antipirina/análogos & derivados , Aquaporina 4/antagonistas & inibidores , Edema Encefálico/tratamento farmacológico , Isquemia Encefálica/complicações , Sequestradores de Radicais Livres/uso terapêutico , Animais , Antipirina/uso terapêutico , Edema Encefálico/etiologia , Modelos Animais de Doenças , Edaravone , Masculino , Ratos
6.
Biochem Biophys Res Commun ; 385(2): 132-6, 2009 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-19379716

RESUMO

High mobility group box-1 (HMGB1), a non-histone DNA-binding protein, is massively released into the extracellular space from neuronal cells after ischemic insult and exacerbates brain tissue damage in rats. Minocycline is a semisynthetic second-generation tetracycline antibiotic which has recently been shown to be a promising neuroprotective agent. In this study, we found that minocycline inhibited HMGB1 release in oxygen-glucose deprivation (OGD)-treated PC12 cells and triggered the activation of p38mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK1/2). The ERK kinase (MEK)1/2 inhibitor U-0126 and p38MAPK inhibitor SB203580 blocked HMGB1 release in response to OGD. Furthermore, HMGB1 triggered cell death in a dose-dependent fashion. Minocycline significantly rescued HMGB1-induced cell death in a dose-dependent manner. In light of recent observations as well as the good safety profile of minocycline in humans, we propose that minocycline might play a potent neuroprotective role through the inhibition of HMGB1-induced neuronal cell death in cerebral infarction.


Assuntos
Apoptose/efeitos dos fármacos , Proteína HMGB1/antagonistas & inibidores , Isquemia/metabolismo , Minociclina/farmacologia , Neurônios/efeitos dos fármacos , Animais , Butadienos/farmacologia , Bovinos , Inibidores Enzimáticos/farmacologia , Glucose/metabolismo , Proteína HMGB1/metabolismo , Isquemia/enzimologia , Isquemia/patologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Nitrilas/farmacologia , Oxigênio/metabolismo , Células PC12 , Ratos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
J Pharmacol Exp Ther ; 329(3): 865-74, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19293391

RESUMO

Edaravone, a potent free radical scavenger, is clinically used for the treatment of cerebral infarction in Japan. Here, we examined the effects of edaravone on the dynamics of high-mobility group box-1 (HMGB1), which is a key mediator of ischemic-induced brain damage, during a 48-h postischemia/reperfusion period in rats and in oxygen-glucose-deprived (OGD) PC12 cells. HMGB1 immunoreactivity was observed in both the cytoplasm and the periphery of cells in the cerebral infarction area 2 h after reperfusion. Intravenous administration of 3 and 6 mg/kg edaravone significantly inhibited nuclear translocation and HMGB1 release in the penumbra area and caused a 26.5 +/- 10.4 and 43.8 +/- 0.5% reduction, respectively, of the total infarct area at 24 h after reperfusion. Moreover, edaravone also decreased plasma HMGB1 levels. In vitro, edaravone dose-dependently (1-10 microM) suppressed OGD- and H(2)O(2)-induced HMGB1 release in PC12 cells. Furthermore, edaravone (3-30 microM) blocked HMGB1-triggered apoptosis in PC12 cells. Our findings suggest a novel neuroprotective mechanism for edaravone that abrogates the release of HMGB1.


Assuntos
Antipirina/análogos & derivados , Infarto Cerebral/tratamento farmacológico , Sequestradores de Radicais Livres/farmacologia , Proteína HMGB1/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Antipirina/farmacologia , Antipirina/uso terapêutico , Apoptose/efeitos dos fármacos , Butadienos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Núcleo Celular/metabolismo , Infarto Cerebral/metabolismo , Infarto Cerebral/patologia , Cérebro/metabolismo , Cérebro/patologia , Citocromos c/metabolismo , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Edaravone , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sequestradores de Radicais Livres/uso terapêutico , Glucose/deficiência , Proteína HMGB1/sangue , Peróxido de Hidrogênio/farmacologia , Masculino , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Nitrilas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Células PC12 , Ratos , Ratos Wistar , Proteínas S100/metabolismo
8.
Biochem Biophys Res Commun ; 377(2): 642-647, 2008 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18940182

RESUMO

Thrombomodulin (TM) is an endothelial cell surface anticoagulant glycoprotein that performs antimetastatic, angiogenic, adhesive, and anti-inflammatory functions in various tissues. It is also expressed in epidermal keratinocytes. We found that a physiological dose (10mJ/cm(2)) of mid-wavelength ultraviolet irradiation (UVB) significantly induced TM expression via the p38mitogen-activated protein kinase (MAPK)/cyclic AMP response element (CRE) signaling pathway in the epidermal keratinocyte cell line HaCaT; this shows that TM regulates the survival of HaCaT cells. SB203580, a p38MAPK inhibitor, significantly decreased TM expression and the viability of cells exposed to UVB. Furthermore, overexpression of TM markedly increased cell viability, and it was abrogated by TM small interfering RNA (siRNA), suggesting that TM may play an important role in exerting cytoprotective effect on epidermal keratinocytes against low-dose UVB.


Assuntos
Epiderme/efeitos da radiação , Queratinócitos/efeitos da radiação , Tolerância a Radiação , Trombomodulina/biossíntese , Raios Ultravioleta , Proteína de Ligação a CREB/metabolismo , Relação Dose-Resposta à Radiação , Células Epidérmicas , Epiderme/metabolismo , Humanos , Imidazóis/farmacologia , Queratinócitos/metabolismo , MAP Quinase Quinase 4/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , RNA Interferente Pequeno/genética , Trombomodulina/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
Cardiovasc Pathol ; 17(3): 129-38, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18402807

RESUMO

BACKGROUND: C-reactive protein (CRP) is widely used as a sensitive biomarker for inflammation. Increasing evidence suggests that CRP plays a role in inflammation. High-mobility group box-1 (HMGB1), a primarily nuclear protein, is passively released into the extracellular milieu by necrotic or damaged cells and is actively secreted by monocytes/macrophages. Extracellular HMGB1 as a potent inflammatory mediator has stimulated immense curiosity in the field of inflammation research. However, the molecular dialogue implicated between CRP and HMGB1 in delayed inflammatory processes remains to be explored. METHODS AND RESULTS: The levels of HMGB1 in culture supernatants were determined by Western blot analysis and enzyme-linked immunosorbent assay in macrophage RAW264.7 cells. Purified CRP induced the release of HMGB1 in a dose- and time-dependent fashion. Immunofluorescence analysis revealed nuclear translocation of HMGB1 in response to CRP. The binding of CRP to the Fc gamma receptor in RAW264.7 cells was confirmed by fluorescence-activated cell sorter analysis. Pretreatment of cells with IgG-Fc fragment, but not IgG-Fab fragment, efficiently blocked this binding. CRP triggered the activation of p38MAPK and ERK1/2, but not Jun N-terminal kinase. Moreover, both p38MAPK inhibitor SB203580 and small interfering RNA significantly suppressed the release of HMGB1, but not the MEK1/2 inhibitor U-0126. CONCLUSION: We demonstrated for the first time that CRP, a prominent risk marker for inflammation including atherosclerosis, could induce the active release of HMGB1 by RAW264.7 cells through Fc gamma receptor/p38MAPK signaling pathways, thus implying that CRP plays a crucial role in the induction, amplification, and prolongation of inflammatory processes, including atherosclerotic lesions.


Assuntos
Proteína C-Reativa/metabolismo , Proteína HMGB1/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Transdução de Sinais/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Western Blotting , Linhagem Celular , Ativação Enzimática/fisiologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunofluorescência , Camundongos , Transporte Proteico/fisiologia , RNA Interferente Pequeno , Transfecção
10.
Xenotransplantation ; 14(6): 636-41, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17991152

RESUMO

High mobility group box-1 (HMGB1) protein, primarily from the nucleus, is released into the extracellular milieu either passively by necrotic or damaged cells, or actively by secretion from monocytes/macrophages. Extracellular HMGB1 acts as a potent inflammatory stimulator by promoting cytokine (for example, tumor necrosis factor-alpha) production, and also has pro-coagulant activity. The signaling pathway initiated by receptor for advanced glycation end-product (RAGE), which is the HMGB1 receptor, also induces complement activation. Recent studies have implicated HMGB1 in acute cardiac allograft rejection, and have identified infiltrating T cells and other damaged cells as its main sources. HMGB1 blockade using the anti-HMGB1 antibody HMGB1 box-A (amino-terminal region) and soluble RAGE rescues mice from acute rejection. We therefore studied the release of HMGB1 in co-cultures of porcine aortic endothelial cells (PAEC) and human leukocytes. Human T cells, but not B cells, monocytes or neutrophils, stimulated significant HMGB1 release in culture with PAEC; this activity required cell-cell contact and was dose-dependent, as determined by Western blotting. The released HMGB1 originated from both cell types, as immunofluorescent microscopy showed that it was present in the cytosol of PAEC in contact with T cells, and had disappeared from the T-cell nuclei. These results demonstrate that direct interactions between PAEC and T cells might be a key factor in triggering HMGB1 release, which suggests that HMGB1 is associated with graft rejection in the early phase.


Assuntos
Endotélio Vascular/metabolismo , Proteína HMGB1/metabolismo , Linfócitos T/metabolismo , Animais , Complexo CD3/análise , Técnicas de Cocultura , Citocinas/fisiologia , Rejeição de Enxerto/fisiopatologia , Humanos , Inflamação , Leucócitos/metabolismo , Suínos , Transplante Heterólogo/imunologia
11.
Cardiovasc Pathol ; 16(3): 136-43, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17502242

RESUMO

BACKGROUND: Chronic inflammation plays a key role in atherogenesis, which is followed by atheromatous plaque instability. High-mobility group box 1 is released by activated macrophages as a late-phase mediator during prolonged inflammation. However, the expression of high-mobility group box 1 and its effect on the production of C-reactive protein and matrix metalloproteinases, particularly on human vascular smooth muscle cells, still remain unknown. METHODS AND RESULTS: Immunohistochemical studies revealed that high-mobility group box 1 was abundantly expressed in vascular smooth muscle cells of carotid and coronary atheromatous plaques, but not in atrophic vascular smooth muscle cells of fibrous plaques and normal medial vascular smooth muscle cells. Receptor for advanced glycation end products was also detected in vascular smooth muscle cells positive for high-mobility group box 1. Moreover, vascular smooth muscle cells positive for high-mobility group box 1 were found to express both C-reactive protein and matrix metalloproteinases (2, 3, and 9). Administration of exogenous high-mobility group box 1 to cultured vascular smooth muscle cells caused a marked elevation of C-reactive protein mRNA by reverse transcriptase-polymerase chain reaction and of C-reactive protein levels by enzyme-linked immunosorbent assay. Conversely, C-reactive protein also triggered a significant release of high-mobility group box 1 in vascular smooth muscle cell culture medium as determined by immunoblot. CONCLUSIONS: Activated vascular smooth muscle cells are the source of high-mobility group box 1 in human advanced atherosclerotic lesions. High-mobility group box 1 directly stimulates the production of both C-reactive protein and matrix metalloproteinase through receptor for advanced glycation end product. These findings provide new evidence that high-mobility group box 1 produced by activated vascular smooth muscle cells may contribute to the progression and vulnerability of human atherosclerotic lesions toward rupture.


Assuntos
Aterosclerose/metabolismo , Doenças das Artérias Carótidas/metabolismo , Doença da Artéria Coronariana/metabolismo , Proteína HMGB1/metabolismo , Músculo Liso Vascular/metabolismo , Aterosclerose/patologia , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Proteína C-Reativa/farmacologia , Doenças das Artérias Carótidas/patologia , Células Cultivadas , Doença da Artéria Coronariana/patologia , Expressão Gênica/efeitos dos fármacos , Proteína HMGB1/farmacologia , Humanos , Técnicas Imunoenzimáticas , Metaloproteinases da Matriz/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , RNA Mensageiro/metabolismo , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/metabolismo
12.
J Biomed Mater Res B Appl Biomater ; 81(2): 456-61, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17022065

RESUMO

We reported earlier that hydroxyapatite (HA) formed on/in agarose gels (HA/agarose) produced by alternate soaking process is a bone-filling material possessing osteoconductive and hemostatic effects. This process could allow us to make bone-like apatite that was formed on/in organic polymer hydrogel matrices. Here, we investigated the mechanism of hemostasis induced by HA/agarose and found that HA/agarose, but not agarose or HA powder, significantly shortened activated partial thromboplastin time (APTT). While HA/agarose did not show significant platelet aggregation, it markedly enhanced adenosine diphosphate (ADP)-induced platelet aggregation. Moreover, Western blot analysis revealed selective adsorption of vitronectin onto HA/agarose. We also observed marked differences between HA powder and HA/agarose in their XRD patterns. The crystallinity of HA powder was much higher compared to that of HA/agarose. Furthermore, 50-100 nm of tube-form aggregations was observed in HA powder on the other hand 100-200 nm of particles was observed in HA/agarose by SEM observation. Thus 100-200 nm of low crystallized particles on the surface structure of HA/agarose may play an important role in hemostasis. Our results demonstrated a crucial role of HA/agarose in the mechanism of hemostasis and suggested a potential role for HA/agarose as a bone-grafting material.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Substitutos Ósseos/isolamento & purificação , Substitutos Ósseos/farmacologia , Durapatita/isolamento & purificação , Durapatita/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Difosfato de Adenosina/farmacologia , Adsorção , Substitutos Ósseos/química , Durapatita/química , Géis , Hemostasia/efeitos dos fármacos , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Tempo de Tromboplastina Parcial , Pós , Tempo de Protrombina , Sefarose , Propriedades de Superfície , Vitronectina/farmacocinética , Difração de Raios X
13.
FEBS Lett ; 580(2): 613-9, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16406050

RESUMO

Anandamide (AEA) exhibits anti-inflammatory effects. However, its role in the periodontal field remains unknown. Here, we found that gingival crevicular fluid contained a detectable level of AEA. The cannabinoid receptors CB1 and CB2 were expressed by human gingival fibroblasts (HGFs), and markedly upregulated under pathological conditions. AEA significantly reduced the production of pro-inflammatory mediators (IL-6, IL-8 and MCP-1) induced by Porphyromonas gingivalis LPS in HGFs, and this effect was attenuated by AM251 and SR144528, selective antagonists of CB1 and CB2, respectively. Moreover, AEA completely blocked LPS-triggered NF-kappaB activation, implying that AEA may regulate hyperinflammatory reactions in periodontitis.


Assuntos
Ácidos Araquidônicos/metabolismo , Moduladores de Receptores de Canabinoides/metabolismo , Endocanabinoides , Gengiva/metabolismo , NF-kappa B/metabolismo , Periodontite , Transdução de Sinais/fisiologia , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Gengiva/química , Gengiva/citologia , Gengiva/patologia , Líquido do Sulco Gengival/química , Gengivite/imunologia , Gengivite/patologia , Humanos , Lipopolissacarídeos/farmacologia , NF-kappa B/antagonistas & inibidores , Periodontite/imunologia , Periodontite/patologia , Alcamidas Poli-Insaturadas , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/metabolismo
14.
FEBS Lett ; 580(2): 703-10, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16412424

RESUMO

Cepharanthine (CEP), a biscoclaurine alkaloid, has been reported to induce cell death, however, the molecular mechanism of this phenomenon remains unclear. We herein report that CEP induced apoptosis in HuH-7 cells through nuclear fragmentation, DNA ladder formation, cytochrome c release, caspase-3 activation and poly-(ADP-ribose)-polymerase cleavage. CEP triggered the generation of reactive oxygen intermediates, the activation of mitogen activated protein kinase (MAPK) p38, JNK1/2 and p44/42, and the downregulation of protein kinase B/Akt. Antioxidants and SP600125, an inhibitor of JNK1/2, but not inhibitors of p38 MAPK and MEK1/2, significantly prevented cell death, thus implying that reactive oxygen species and JNK1/2 play crucial roles in the CEP-induced apoptosis of HuH-7 cells.


Assuntos
Alcaloides/metabolismo , Anti-Inflamatórios não Esteroides/metabolismo , Apoptose/fisiologia , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Antracenos/metabolismo , Benzilisoquinolinas , Caspase 3 , Caspases/metabolismo , Linhagem Celular Tumoral , Colágeno Tipo XI/metabolismo , Citocromos c/metabolismo , Regulação para Baixo , Ativação Enzimática , Inibidores Enzimáticos/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Pathophysiol Haemost Thromb ; 34(1): 41-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16293985

RESUMO

Thrombin, a serine protease that plays a pivotal role in blood coagulation, wound healing, and angiogenesis, has also been implicated in the mitogenesis of various cell types. Previously, we showed that thrombin and the thrombin receptor agonist peptide (TRAP-14; SFLLRNPNDKYEPF) for protease-activated receptor 1 (PAR1) induce vascular endothelial growth factor (VEGF) secretion in PC-12 cells. In this study, we show that thrombin and TRAP-14 also stimulate VEGF secretion in the human NB-1 neuroblastoma cells. In these cells, we further show that thrombin-induced VEGF secretion was blocked by cycloheximide and actinomycin D, indicating that de novo protein synthesis is essential for this process. Reduced thrombin-induced VEGF secretion upon treatment with LY294002, calphostin C, or BAPTA, further suggests that the process is dependent on phosphatidyl-inositol-3-kinase, protein kinase C, and calcium. However, the complete loss of thrombin-induced VEGF production upon treatment with argatroban, a derivative of arginine and a potent anticoagulant/antithrombin agent, supports the notion that argatroban serves as a useful therapeutic tool for thrombin-associated pathologic conditions. Here, it appears that argatroban may be effective in controlling disorders linked to thrombin-induced VEGF production in neuronal cells.


Assuntos
Hemostáticos/farmacologia , Neuroblastoma/metabolismo , Ácidos Pipecólicos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Trombina/farmacologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Arginina/análogos & derivados , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Células PC12 , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C/metabolismo , Ratos , Sulfonamidas
16.
J Immunol ; 174(9): 5796-804, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15843583

RESUMO

Dental pulp inflammation often results from dissemination of periodontitis caused mostly by Porphyromonas gingivalis infection. Calcitonin gene-related peptide and substance P are proinflammatory neuropeptides that increase in inflamed pulp tissue. To study an involvement of the periodontitis pathogen and neuropeptides in pulp inflammation, we investigated human dental pulp cell neuropeptide release by arginine-specific cysteine protease (RgpB), a cysteine proteinase of P. gingivalis, and participating signaling pathways. RgpB induced neuropeptide release from cultured human pulp cells (HPCs) in a proteolytic activity-dependent manner at a range of 12.5-200 nM. HPCs expressed both mRNA and the products of calcitonin gene-related peptide, substance P, and proteinase-activated receptor-2 (PAR-2) that were also found in dental pulp fibroblast-like cells. The PAR-2 agonists, SLIGKV and trypsin, also induced neuropeptide release from HPCs, and HPC PAR-2 gene knockout by transfection of PAR-2 antisense oligonucleotides inhibited significantly the RgpB-elicited neuropeptide release. These results indicated that RgpB-induced neuropeptide release was dependent on PAR-2 activation. The kinase inhibitor profile on the RgpB-neuropeptide release from HPC revealed a new PAR-2 signaling pathway that was mediated by p38 MAPK and activated transcription factor-2 activation, in addition to the PAR-2-p44/42 p38MAPK and -AP-1 pathway. This new RgpB activity suggests a possible link between periodontitis and pulp inflammation, which may be modulated by neuropeptides released in the lesion.


Assuntos
Cisteína Endopeptidases/fisiologia , Polpa Dentária/enzimologia , Polpa Dentária/metabolismo , Hemaglutininas/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Neuropeptídeos/metabolismo , Porphyromonas gingivalis/fisiologia , Receptor PAR-2/fisiologia , Fator 2 Ativador da Transcrição , Adesinas Bacterianas , Peptídeo Relacionado com Gene de Calcitonina/biossíntese , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Linhagem Celular Tumoral , Sistema Livre de Células/metabolismo , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Polpa Dentária/citologia , Ativação Enzimática/fisiologia , Cisteína Endopeptidases Gingipaínas , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Neuropeptídeos/biossíntese , Receptor PAR-2/agonistas , Receptor PAR-2/biossíntese , Receptor PAR-2/deficiência , Substância P/biossíntese , Substância P/metabolismo , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Hepatology ; 38(5): 1167-77, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14578855

RESUMO

The endogenous cannabinoid anandamide, a lipid mediator, induces various physiologic events such as vascular relaxation, inhibition of gap-junctions formation, tumor proliferation, neurologic analgesia, and apoptosis. Although increased concentration of anandamide in plasma has been implicated in pathophysiologic states including endotoxin-induced hypotension, the effects of anandamide on hepatocytes still remain unclear. In this study, we present evidence that plasma anandamide concentration is highly increased in severe hepatitis and cirrhosis patients. In addition, concentrations of anandamide within the pathophysiologic range potently induced apoptosis of hepatoma cell line (Hep G2) and primary hepatocytes, suggesting a possible link between increased anandamide level and hepatocyte damage. Anandamide-induced cell death was preceded by G0/G1 cell-cycle arrest, activation of proapoptotic signaling (i.e., p38 MAPK and JNK), and inhibition of antiapoptotic signaling (i.e., PKB/Akt) pathways. Moreover, anandamide increased susceptibility to oxidative stress-induced hepatocyte damage. In this context, methyl-beta-cyclodextrin (MCD), a membrane cholesterol depletor, or mevastatin, an HMG-CoA reductase inhibitor, or N-acetyl cysteine, an antioxidant, potently inhibited the anandamide-induced proapoptotic events and cell death, whereas putative cannabinoid receptor antagonists did not exhibit an inhibitory effect on anandamide-induced cell death. Furthermore, binding assay using polymyxin beads revealed that anandamide could interact with cholesterol. In conclusion, our data suggest that cholesterol present in the cell membrane determines the fate of hepatocytes exposed to anandamide, possibly functioning as an anandamide receptor.


Assuntos
Apoptose/fisiologia , Ácidos Araquidônicos/fisiologia , Moduladores de Receptores de Canabinoides/fisiologia , Colesterol/fisiologia , Hepatócitos/fisiologia , Animais , Ácidos Araquidônicos/sangue , Moduladores de Receptores de Canabinoides/sangue , Membrana Celular/metabolismo , Células Cultivadas , Endocanabinoides , Feminino , Hepatite/sangue , Humanos , Estresse Oxidativo/fisiologia , Alcamidas Poli-Insaturadas , Ratos , Ratos Wistar
18.
J Neurochem ; 85(1): 50-61, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12641726

RESUMO

Anandamide is a neuroimmunoregulatory molecule that triggers apoptosis in a number of cell types including PC12 cells. Here, we investigated the molecular mechanisms underlying anandamide-induced cell death in PC12 cells. Anandamide treatment resulted in the activation of p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), and p44/42 MAPK in apoptosing cells. A selective p38 MAPK inhibitor, SB203580, or dn-JNK, JNK1(A-F) or SAPKbeta(K-R), blocked anandamide-induced cell death, whereas a specific inhibitor of MEK-1/2, U0126, had no effect, indicating that activation of p38 MAPK and JNK is critical in anandamide-induced cell death. An important role for apoptosis signal-regulating kinase 1 (ASK1) in this event was also demonstrated by the inhibition of p38 MAPK/JNK activation and death in cells overexpressing dn-ASK1, ASK1 (K709M). Conversely, the constitutively active ASK1, ASK1DeltaN, caused prolonged p38 MAPK/JNK activation and increased cell death. These indicate that ASK1 mediates anandamide-induced cell death via p38 MAPK and JNK activation. Here, we also found that activation of p38 MAPK/JNK is accompanied by cytochrome c release from the mitochondria and caspase activation (which can be inhibited by SB203580), suggesting that anandamide triggers a mitochondrial dependent apoptotic pathway. The caspase inhibitor, zVAD, and the mitochondrial pore opening inhibitor, cyclosporine A, blocked anandamide-induced cell death but not p38 MAPK/JNK activation, suggesting that activation of these kinases may occur upstream of mitochondrial associated events.


Assuntos
Ácidos Araquidônicos/farmacologia , MAP Quinase Quinase Quinases/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Feocromocitoma/tratamento farmacológico , Transdução de Sinais/fisiologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Relação Dose-Resposta a Droga , Endocanabinoides , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , MAP Quinase Quinase Quinase 5 , MAP Quinase Quinase Quinases/genética , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/genética , Células PC12 , Feocromocitoma/metabolismo , Alcamidas Poli-Insaturadas , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/farmacologia , Ratos , Receptores de Canabinoides , Receptores de Droga/antagonistas & inibidores , Receptores de Droga/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transfecção , Proteínas Quinases p38 Ativadas por Mitógeno
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...