Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Mol Sci ; 22(18)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34576111

RESUMO

Mitochondrial functional abnormalities or quantitative decreases are considered to be one of the most plausible pathogenic mechanisms of Parkinson's disease (PD). Thus, mitochondrial complex inhibitors are often used for the development of experimental PD. In this study, we used rotenone to create in vitro cell models of PD, then used these models to investigate the effects of 1,5-anhydro-D-fructose (1,5-AF), a monosaccharide with protective effects against a range of cytotoxic substances. Subsequently, we investigated the possible mechanisms of these protective effects in PC12 cells. The protection of 1,5-AF against rotenone-induced cytotoxicity was confirmed by increased cell viability and longer dendritic lengths in PC12 and primary neuronal cells. Furthermore, in rotenone-treated PC12 cells, 1,5-AF upregulated peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) expression and enhanced its deacetylation, while increasing AMP-activated protein kinase (AMPK) phosphorylation. 1,5-AF treatment also increased mitochondrial activity in these cells. Moreover, PGC-1α silencing inhibited the cytoprotective and mitochondrial biogenic effects of 1,5-AF in PC12 cells. Therefore, 1,5-AF may activate PGC-1α through AMPK activation, thus leading to mitochondrial biogenic and cytoprotective effects. Together, our results suggest that 1,5-AF has therapeutic potential for development as a treatment for PD.


Assuntos
Frutose/análogos & derivados , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Biogênese de Organelas , Rotenona/toxicidade , Adenilato Quinase/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Frutose/química , Frutose/farmacologia , Inativação Gênica/efeitos dos fármacos , Metformina/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Células PC12 , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosforilação/efeitos dos fármacos , Ratos
2.
Biomed Rep ; 14(2): 21, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33335727

RESUMO

Nucleophosmin 1 (NPM1) primarily localizes to the nucleus and is passively released into the extracellular milieu by necrotic or damaged cells, or is secreted by monocytes and macrophages. Extracellular NPM1 acts as a potent inflammatory stimulator by promoting cytokine production [e.g., tumor necrosis factor-α (TNF-α)], which suggests that NPM1 acts as a damage-associated molecular pattern. However, the receptor of NPM1 is unknown. Evidence indicates that DAMPs, which include high mobility group box 1 and histones, may bind Toll-like receptors (TLRs). In the present study, it was shown that NPM1 signaling was mediated via the TLR4 pathway, which suggests that TLR4 is an NPM1 receptor. TLR4 binds myeloid differentiation protein-2 (MD-2), which is essential for intracellular signaling. Furthermore, the TLR4 antagonist, LPS-Rhodobacter sphaeroides (an MD-2 antagonist) and TAK-242 (a TLR4 signaling inhibitor) significantly inhibited NPM1-induced TNF-α production by differentiated THP-1 cells as well as reducing ERK1/2 activation. Far-western blot analysis revealed that NPM1 directly bound MD-2. Thus, the results of the present study provide compelling evidence that TLR4 binds NPM1, and it is hypothesized that inhibiting NPM1 activity may serve as a novel strategy for treating TLR4-related diseases.

3.
Int J Mol Sci ; 21(11)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492845

RESUMO

Perineural adhesions leading to neuropathy are one of the most undesirable consequences of peripheral nerve surgery. However, there are currently no widely used compounds with anti-adhesive effects in the field of peripheral nerve surgery. E8002 is a novel, anti-adhesive, multi-layer membrane that contains L-ascorbic acid (AA). Here, we investigated the effect and mechanism of E8002 in a rat sciatic nerve adhesion model. A total of 21 rats were used. Six weeks after surgery, macroscopic adhesion scores were significantly lower in the E8002 group (adhesion procedure followed by nerve wrapping with E8002) compared to the E8002 AA(-) group (adhesion procedure followed by nerve wrapping with the E8002 membrane excluding AA) and adhesion group (adhesion procedure but no treatment). Correspondingly, a microscopic examination revealed prominent scar tissue in the E8002 AA(-) and adhesion groups. Furthermore, an in vitro study using human blood samples showed that AA enhanced tissue-type, plasminogen activator-mediated fibrinolysis. Altogether, these results suggest that E8002 may exert an anti-adhesive action via AA and the regulation of fibrinolysis.


Assuntos
Ácido Ascórbico/química , Poliésteres/química , Nervo Isquiático/efeitos dos fármacos , Aderências Teciduais/prevenção & controle , Cicatrização/efeitos dos fármacos , Adulto , Animais , Antioxidantes/química , Materiais Biocompatíveis/química , Cicatriz , Feminino , Fibrinólise , Humanos , Masculino , Membranas Artificiais , Pessoa de Meia-Idade , Polímeros/química , Ratos , Ratos Sprague-Dawley , Terapia Trombolítica
4.
Sci Rep ; 8(1): 15844, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367108

RESUMO

Uric acid (UA) therapy may prevent early ischemic worsening after acute stroke in thrombolysis patients. The aim of this study was to examine the influence of UA on the thrombolytic efficacy of alteplase in human blood samples by measuring thrombolysis under flow conditions using a newly developed microchip-based flow-chamber assay. Human blood samples from healthy volunteers were exposed to UA, alteplase, or a combination of UA and alteplase. Whole blood and platelet-rich plasma were perfused over a collagen- and thromboplastin-coated microchip, and capillary occlusion was monitored with a video microscope and flow-pressure sensor. The area under the curve (extent of thrombogenesis or thrombolysis) at 30 minutes was 92% lower in the UA-alteplase-treated group compared with the alteplase-treated group. D-dimers were measured to evaluate these effects in human platelet-poor plasma samples. Although hydrogen peroxide significantly decreased the elevation of D-dimers by alteplase, UA significantly inhibited the effect of hydrogen peroxide. Meanwhile, rat models of thromboembolic cerebral ischemia were treated with either alteplase or UA-alteplase combination therapy. Compared with alteplase alone, the combination therapy reduced the infarct volume and inhibited haemorrhagic transformation. UA enhances alteplase-mediated thrombolysis, potentially by preventing oxidative stress, which inhibits fibrinolysis by alteplase in thrombi.


Assuntos
Antioxidantes/farmacologia , Fibrinólise/efeitos dos fármacos , Ativador de Plasminogênio Tecidual/farmacologia , Ácido Úrico/farmacologia , Adulto , Animais , Antioxidantes/uso terapêutico , Área Sob a Curva , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Isquemia/tratamento farmacológico , Isquemia/patologia , Masculino , Microscopia de Vídeo , Estresse Oxidativo/efeitos dos fármacos , Curva ROC , Ratos , Ratos Sprague-Dawley , Ativador de Plasminogênio Tecidual/uso terapêutico , Ácido Úrico/uso terapêutico , Adulto Jovem
5.
Int J Mol Sci ; 19(5)2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29783695

RESUMO

Neuropathic pain after spinal surgery, so-called failed back surgery syndrome, is a frequently observed common complication. One cause of the pain is scar tissue formation, observed as post-surgical epidural adhesions. These adhesions may compress surrounding spinal nerves, resulting in pain, even after successful spinal surgery. E8002 is an anti-adhesive membrane. In Japan, a clinical trial of E8002 is currently ongoing in patients undergoing abdominal surgery. However, animal experiments have not been performed for E8002 in spinal surgery. We assessed the anti-adhesive effect of E8002 in a rat laminectomy model. The dura matter was covered with an E8002 membrane or left uncovered as a control. Neurological evaluations and histopathological findings were compared at six weeks postoperatively. Histopathological analyses were performed by hematoxylin⁻eosin and aldehyde fuchsin-Masson Goldner staining. Three assessment areas were selected at the middle and margins of the laminectomy sites, and the numbers of fibroblasts and inflammatory cells were counted. Blinded histopathological evaluation revealed that adhesions and scar formation were reduced in the E8002 group compared with the control group. The E8002 group had significantly lower numbers of fibroblasts and inflammatory cells than the control group. The present results indicate that E8002 can prevent epidural scar adhesions after laminectomy.


Assuntos
Laminectomia/métodos , Membranas Artificiais , Aderências Teciduais/prevenção & controle , Animais , Laminectomia/efeitos adversos , Masculino , Ratos , Ratos Sprague-Dawley
6.
Oxid Med Cell Longev ; 2017: 6873281, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29259732

RESUMO

The combination of alteplase, a recombinant tissue plasminogen activator, and edaravone, an antioxidant, reportedly enhances recanalization after acute ischemic stroke. We examined the influence of edaravone on the thrombolytic efficacy of alteplase by measuring thrombolysis using a newly developed microchip-based flow-chamber assay. Rat models of embolic cerebral ischemia were treated with either alteplase or alteplase-edaravone combination therapy. The combination therapy significantly reduced the infarct volume and improved neurological deficits. Human blood samples from healthy volunteers were exposed to edaravone, alteplase, or a combination of alteplase and edaravone or hydrogen peroxide. Whole blood was perfused over a collagen- and thromboplastin-coated microchip; capillary occlusion was monitored with a video microscope and flow-pressure sensor. The area under the curve (extent of thrombogenesis or thrombolysis) at 30 minutes was 69.9% lower in the edaravone-alteplase- than alteplase-treated group. The thrombolytic effect of alteplase was significantly attenuated in the presence of hydrogen peroxide, suggesting that oxidative stress might hinder thrombolysis. D-dimers were measured to evaluate these effects in human platelet-poor plasma samples. Although hydrogen peroxide significantly decreased the elevation of D-dimers by alteplase, edaravone significantly inhibited the decrease. Edaravone enhances alteplase-mediated thrombolysis, likely by preventing oxidative stress, which inhibits fibrinolysis by alteplase in thrombi.


Assuntos
Antipirina/análogos & derivados , Sequestradores de Radicais Livres/uso terapêutico , Terapia Trombolítica/métodos , Adulto , Animais , Antipirina/farmacologia , Antipirina/uso terapêutico , Edaravone , Sequestradores de Radicais Livres/farmacologia , Humanos , Masculino , Ratos , Ratos Sprague-Dawley
7.
Med Hypotheses ; 85(5): 618-21, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26305447

RESUMO

Periodontitis is a chronic inflammatory disease that affects the tooth-supporting tissues. Gingival fibroblasts are the most abundant cells in periodontal tissues and they participate actively in the host inflammatory response to periodontal pathogens that is known to mediate local tissue destruction in periodontitis. The Japanese apricot, known as Ume in Japanese, has been a traditional Japanese medicine for centuries and is a familiar and commonly consumed food. The health benefits of Ume are widely recognized and have been confirmed in recent studies showing that MK615, an extract of compounds from Ume, has strong anticancer and anti-inflammatory effects. However, the potential role of MK615 in oral health is unknown. We hypothesized that the anti-inflammatory activities of MK615 could be exploited to inhibit the effects of lipopolysaccharide (LPS) produced by periodontal bacterial pathogens, such as Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Here, we show that LPS-induced interleukin (IL)-6 and IL-8 production by gingival fibroblasts was dose-dependently inhibited by MK615. As a potent inhibitor of the inflammatory responses induced by periodontal pathogens, MK615 merits further testing as a therapeutic agent in inflammatory diseases such as periodontitis.


Assuntos
Anti-Inflamatórios/uso terapêutico , Periodontite/tratamento farmacológico , Células Cultivadas , Humanos
8.
EMBO J ; 34(8): 1042-55, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25698262

RESUMO

Obesity is a major global public health problem, and understanding its pathogenesis is critical for identifying a cure. In this study, a gene knockout strategy was used in post-neonatal mice to delete synoviolin (Syvn)1/Hrd1/Der3, an ER-resident E3 ubiquitin ligase with known roles in homeostasis maintenance. Syvn1 deficiency resulted in weight loss and lower accumulation of white adipose tissue in otherwise wild-type animals as well as in genetically obese (ob/ob and db/db) and adipose tissue-specific knockout mice as compared to control animals. SYVN1 interacted with and ubiquitinated the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1ß, and Syvn1 mutants showed upregulation of PGC-1ß target genes and increase in mitochondrion number, respiration, and basal energy expenditure in adipose tissue relative to control animals. Moreover, the selective SYVN1 inhibitor LS-102 abolished the negative regulation of PGC-1ß by SYVN1 and prevented weight gain in mice. Thus, SYVN1 is a novel post-translational regulator of PGC-1ß and a potential therapeutic target in obesity treatment.


Assuntos
Peso Corporal/genética , Mitocôndrias/fisiologia , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Células 3T3-L1 , Animais , Células Cultivadas , Regulação para Baixo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Obesidade/genética , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética
9.
PLoS One ; 10(2): e0117775, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25688865

RESUMO

BACKGROUND/PURPOSE: Lysine-specific gingipain (Kgp) is a virulence factor secreted from Porphyromonas gingivalis (P. gingivalis), a major etiological bacterium of periodontal disease. Keratin intermediate filaments maintain the structural integrity of gingival epithelial cells, but are targeted by Kgp to produce a novel cytokeratin 6 fragment (K6F). We investigated the release of K6F and its induction of cytokine secretion. METHODS: K6F present in the gingival crevicular fluid of periodontal disease patients and in gingipain-treated rat gingival epithelial cell culture supernatants was measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometer-based rapid quantitative peptide analysis using BLOTCHIP. K6F in gingival tissues was immunostained, and cytokeratin 6 protein was analyzed by immunofluorescence staining and flow cytometry. Activation of MAPK in gingival epithelial cells was evaluated by immunoblotting. ELISA was used to measure K6F and the cytokines release induced by K6F. Human gingival fibroblast migration was assessed using a Matrigel invasion chamber assay. RESULTS: We identified K6F, corresponding to the C-terminus region of human cytokeratin 6 (amino acids 359-378), in the gingival crevicular fluid of periodontal disease patients and in the supernatant from gingival epithelial cells cultured with Kgp. K6F antigen was distributed from the basal to the spinous epithelial layers in gingivae from periodontal disease patients. Cytokeratin 6 on gingival epithelial cells was degraded by Kgp, but not by Arg-gingipain, P. gingivalis lipopolysaccharide or Actinobacillus actinomycetemcomitans lipopolysaccharide. K6F, but not a scrambled K6F peptide, induced human gingival fibroblast migration and secretion of interleukin (IL)-6, IL-8 and monocyte chemoattractant protein-1. These effects of K6F were mediated by activation of p38 MAPK and Jun N-terminal kinase, but not p42/44 MAPK or p-Akt. CONCLUSION: Kgp degrades gingival epithelial cell cytokeratin 6 to K6F that, on release, induces invasion and cytokine secretion by human gingival fibroblasts. Thus, Kgp may contribute to the development of periodontal disease.


Assuntos
Adesinas Bacterianas/farmacologia , Cisteína Endopeptidases/farmacologia , Gengiva/metabolismo , Líquido do Sulco Gengival/metabolismo , Queratina-6/metabolismo , Periodontite/metabolismo , Animais , Células Cultivadas , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Cisteína Endopeptidases Gingipaínas , Gengiva/efeitos dos fármacos , Gengiva/patologia , Líquido do Sulco Gengival/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Inflamação/patologia , Periodontite/patologia , Porphyromonas gingivalis , Ratos , Transdução de Sinais/efeitos dos fármacos
10.
PLoS One ; 9(7): e102482, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25032709

RESUMO

RATIONALE: Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance leading to right ventricular failure and death. Recent studies have suggested that chronic inflammatory processes are involved in the pathogenesis of PAH. However, the molecular and cellular mechanisms driving inflammation have not been fully elucidated. OBJECTIVES: To elucidate the roles of high mobility group box 1 protein (HMGB1), a ubiquitous DNA-binding protein with extracellular pro-inflammatory activity, in a rat model of PAH. METHODS: Male Sprague-Dawley rats were administered monocrotaline (MCT). Concentrations of HMGB1 in bronchoalveolar lavage fluid (BALF) and serum, and localization of HMGB1 in the lung were examined over time. The protective effects of anti-HMGB1 neutralizing antibody against MCT-induced PAH were tested. RESULTS: HMGB1 levels in BALF were elevated 1 week after MCT injection, and this elevation preceded increases of other pro-inflammatory cytokines, such as TNF-α, and the development of PAH. In contrast, serum HMGB1 levels were elevated 4 weeks after MCT injection, at which time the rats began to die. Immunohistochemical analyses indicated that HMGB1 was translocated to the extranuclear space in periarterial infiltrating cells, alveolar macrophages, and bronchial epithelial cells of MCT-injected rats. Anti-HMGB1 neutralizing antibody protected rats against MCT-induced lung inflammation, thickening of the pulmonary artery wall, and elevation of right ventricular systolic pressure, and significantly improved the survival of the MCT-induced PAH rats. CONCLUSIONS: Our results identify extracellular HMGB1 as a promoting factor for MCT-induced PAH. The blockade of HMGB1 activity improved survival of MCT-induced PAH rats, and thus might be a promising therapy for the treatment of PAH.


Assuntos
Proteína HMGB1/metabolismo , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/fisiopatologia , Resistência Vascular/fisiologia , Disfunção Ventricular Direita/fisiopatologia , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiocina CCL2/sangue , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Endotelina-1/sangue , Proteína HMGB1/sangue , Hemodinâmica , Inflamação/imunologia , Inflamação/fisiopatologia , Interleucina-1beta/sangue , Masculino , Monocrotalina , Artéria Pulmonar/fisiopatologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue
11.
PLoS One ; 8(9): e75961, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098750

RESUMO

INTRODUCTION: Recent studies have shown that histones, the chief protein component of chromatin, are released into the extracellular space during sepsis, trauma, and ischemia-reperfusion injury, and act as major mediators of the death of an organism. This study was designed to elucidate the cellular and molecular basis of histone-induced lethality and to assess the protective effects of recombinant thrombomodulin (rTM). rTM has been approved for the treatment of disseminated intravascular coagulation (DIC) in Japan, and is currently undergoing a phase III clinical trial in the United States. METHODS: Histone H3 levels in plasma of healthy volunteers and patients with sepsis and DIC were measured using enzyme-linked immunosorbent assay. Male C57BL/6 mice were injected intravenously with purified histones, and pathological examinations were performed. The protective effects of rTM against histone toxicity were analyzed both in vitro and in mice. RESULTS: Histone H3 was not detectable in plasma of healthy volunteers, but significant levels were observed in patients with sepsis and DIC. These levels were higher in non-survivors than in survivors. Extracellular histones triggered platelet aggregation, leading to thrombotic occlusion of pulmonary capillaries and subsequent right-sided heart failure in mice. These mice displayed symptoms of DIC, including thrombocytopenia, prolonged prothrombin time, decreased fibrinogen, fibrin deposition in capillaries, and bleeding. Platelet depletion protected mice from histone-induced death in the first 30 minutes, suggesting that vessel occlusion by platelet-rich thrombi might be responsible for death during the early phase. Furthermore, rTM bound to extracellular histones, suppressed histone-induced platelet aggregation, thrombotic occlusion of pulmonary capillaries, and dilatation of the right ventricle, and rescued mice from lethal thromboembolism. CONCLUSIONS: Extracellular histones cause massive thromboembolism associated with consumptive coagulopathy, which is diagnostically indistinguishable from DIC. rTM binds to histones and neutralizes the prothrombotic action of histones. This may contribute to the effectiveness of rTM against DIC.


Assuntos
Coagulação Intravascular Disseminada/sangue , Histonas/efeitos adversos , Proteínas Recombinantes/farmacologia , Sepse/sangue , Tromboembolia/prevenção & controle , Trombomodulina/genética , Animais , Eletrocardiografia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Histonas/sangue , Immunoblotting , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/genética , Tromboembolia/etiologia
12.
Int J Mol Sci ; 14(9): 18899-924, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24065095

RESUMO

Stroke is a major cause of mortality and disability worldwide. The main cause of stroke is atherosclerosis, and the most common risk factor for atherosclerosis is hypertension. Therefore, antihypertensive treatments are recommended for the prevention of stroke. Three angiotensin receptor blockers (ARBs), telmisartan, irbesartan and candesartan, inhibit the expression of the receptor for advanced glycation end-products (RAGE), which is one of the pleiotropic effects of these drugs. High mobility group box 1 (HMGB1) is the ligand of RAGE, and has been recently identified as a lethal mediator of severe sepsis. HMGB1 is an intracellular protein, which acts as an inflammatory cytokine when released into the extracellular milieu. Extracellular HMGB1 causes multiple organ failure and contributes to the pathogenesis of hypertension, hyperlipidemia, diabetes mellitus, atherosclerosis, thrombosis, and stroke. This is the first review of the literature evaluating the potential of three ARBs for the HMGB1-RAGE axis on stroke therapy, including prevention and acute treatment. This review covers clinical and experimental studies conducted between 1976 and 2013. We propose that ARBs, which inhibit the HMGB1/RAGE axis, may offer a novel option for prevention and acute treatment of stroke. However, additional clinical studies are necessary to verify the efficacy of ARBs.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Proteína HMGB1/metabolismo , Receptores Imunológicos/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Doença Aguda , Antagonistas de Receptores de Angiotensina/farmacologia , Animais , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Proteína HMGB1/antagonistas & inibidores , Humanos , Hipertensão/tratamento farmacológico , Irbesartana , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/antagonistas & inibidores , Fatores de Risco , Acidente Vascular Cerebral/prevenção & controle , Telmisartan , Tetrazóis/farmacologia , Tetrazóis/uso terapêutico
13.
Biochem Biophys Res Commun ; 437(4): 573-8, 2013 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-23850687

RESUMO

Chronic low-grade inflammation is a key contributor to high-fat diet (HFD)-related diseases, such as type 2 diabetes, non-alcoholic steatohepatitis, and atherosclerosis. The inflammation is characterized by infiltration of inflammatory cells, particularly macrophages, into obese adipose tissue. However, the molecular mechanisms by which a HFD induces low-grade inflammation are poorly understood. Here, we show that histone H3, a major protein component of chromatin, is released into the extracellular space when mice are fed a HFD or macrophages are stimulated with the saturated fatty acid palmitate. In a murine macrophage cell line, RAW 264.7, palmitate activated reactive oxygen species (ROS) production and JNK signaling. Inhibitors of these pathways dampened palmitate-induced histone H3 release, suggesting that the extracellular release of histone H3 was mediated, in part, through ROS and JNK signaling. Extracellular histone activated endothelial cells to express the adhesion molecules ICAM-1 and VCAM-1 and the procoagulant molecule tissue factor, which are known to contribute to inflammatory cell recruitment and thrombosis. These results suggest the possible contribution of extracellular histone to the pathogenesis of HFD-induced inflammation and thrombosis.


Assuntos
Dieta Hiperlipídica , Histonas/metabolismo , Inflamação/metabolismo , Ácido Palmítico/metabolismo , Trombose/metabolismo , Tecido Adiposo/metabolismo , Animais , Adesão Celular , Linhagem Celular , Sobrevivência Celular , Coagulantes/metabolismo , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , MAP Quinase Quinase 4/metabolismo , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
14.
Brain Tumor Pathol ; 30(1): 28-33, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22426543

RESUMO

Many vestibular schwannomas (VS) manifest intratumoral microhemorrhages whose underlying mechanisms are not fully understood. Thrombomodulin (TM) is an endothelial anticoagulant cofactor that promotes the thrombin-mediated formation of activated protein C that inhibits thrombus formation. We investigated the existence of TM in VS and its potential role in the development of microhemorrhages. We used immunohistochemical staining to study the expression of TM in tissues derived from 25 patients with VS. Hemosiderin deposition was examined by Berlin blue staining and compared with the expression of TM. Vascular endothelial cells in all 25 VS tissues expressed TM. The TM-positive vessel ratio, calculated by dividing the number of TM-positive by the number of CD34-positive lumens, was significantly higher in hemosiderin-laden than hemosiderin-negative tissues (0.71 ± 0.17 vs. 0.53 ± 0.31, p = 0.049, Mann-Whitney U test). Our findings suggest a close relationship between the expression of TM and microhemorrhage in VS.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Neuroma Acústico/metabolismo , Trombomodulina/metabolismo , Adulto , Idoso , Células Endoteliais/patologia , Endotélio Vascular/patologia , Feminino , Hemossiderina/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/patologia , Estudos Retrospectivos
15.
Biomed Rep ; 1(1): 7-12, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24648884

RESUMO

Acute ischemic stroke (AIS) is a major cause of morbidity and mortality in the aging population worldwide. Alteplase, a recombinant tissue plasminogen activator, is the only Food and Drug Administration-approved thrombolytic agent for the treatment of AIS. Only 2-5% of patients with stroke receive thrombolytic treatment, mainly due to delay in reaching the hospital. Edaravone is a free radical scavenger marketed in Japan to treat patients with AIS, who present within 24 h of the onset of symptoms. When used in combination with alteplase, edaravone may have three useful effects: enhancement of early recanalization, inhibition of alteplase-induced hemorrhagic transformation and extension of the therapeutic time window for alteplase. This is the first review of the literature evaluating the clinical efficacy of edaravone, aiming to clarify whether edaravone should be further evaluated for clinical use worldwide. This review covers both clinical and experimental studies conducted between 1994 and 2012. Edaravone is a potentially useful neurovascular protective agent, used in combination with thrombolytic agents to treat >15 million patients devastated by stroke worldwide annually. Additional clinical studies are necessary to verify the efficacy of edaravone when used in combination with a thrombolytic agent.

16.
Exp Ther Med ; 4(1): 3-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23060914

RESUMO

Stroke is a major cause of mortality and disability worldwide. During the past three decades, major advances have occurred in secondary prevention, which have demonstrated the broader potential for the prevention of stroke. Risk factors for stroke include previous stroke or transient ischemic attack, hypertension, high blood cholesterol and diabetes. Proven secondary prevention strategies are anti-platelet agents, antihypertensive drugs, statins and glycemic control. In the present review, we evaluated the secondary prevention of stroke in light of clinical studies and discuss new pleiotropic effects beyond the original effects and emerging clinical evidence, with a focus on the effect of optimal oral pharmacotherapy.

17.
Exp Ther Med ; 3(1): 3-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22969835

RESUMO

Free radicals play an important role in the pathogenesis of a variety of diseases; thus, they are an attractive target for therapeutic intervention in these diseases. Compounds capable of scavenging free radicals have been developed for this purpose and some, developed for the treatment of cerebral ischemic stroke, have progressed to clinical trials. One such scavenger, edaravone, is used to treat patients within 24 h of stroke. Edaravone, which can diffuse into many disease-affected organs, also shows protective effects in the heart, lung, intestine, liver, pancreas, kidney, bladder and testis. As well as scavenging free radicals, edaravone has anti-apoptotic, anti-necrotic and anti-cytokine effects in various diseases. Here, we critically review the literature on its clinical efficacy and examine whether edaravone should be considered a candidate for worldwide development, focusing on its effects on diseases other than cerebral infarction. Edaravone has been safely used as a free radical scavenger for more than 10 years; we propose that edaravone may offer a novel treatment option for several diseases.

18.
World J Gastroenterol ; 18(31): 4118-26, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22919243

RESUMO

AIM: To investigate the hepatoprotective effect of MK615, a Japanese apricot extract, in an animal model, and its clinical therapeutic effect. METHODS: Wistar rats were administered physiological saline (4 mL/kg) or MK615 solution (4 mL/kg) for 7 d. On the sixth d, acute hepatic injury was induced by administering a single intraperitoneal injection (ip) of D-galactosamine hydrochloride (D-GalN) (600 mg/kg). Plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined, and liver tissues were used for histopathological analysis. Fifty-eight patients with liver disorders [hepatitis C (n = 40), non-alcoholic fatty liver disease (n = 15), and autoimmune liver disease (n = 3)] were orally administered commercially available Misatol ME-containing MK615 (13 g/d) daily for 12 wk. Blood and urine were sampled immediately before and 6 wk, 12 wk, and 16 wk after the start of intake to measure various biochemical parameters. The percentage change in ALT and AST levels after 12 wk from the pre-intake baseline served as a primary endpoint. RESULTS: D-GalN effectively induced acute hepatic injury in the rats. At 48 h after the ip injection of D-GalN, the plasma levels of ALT (475.6 ± 191.5 IU/L vs 225.3 ± 194.2 IU/L, P < 0.05) and AST (1253.9 ± 223.4 IU/L vs 621.9 ± 478.2 IU/L, P < 0.05) in the MK615 group were significantly lower than the control group. Scattered single cell necrosis, loss of hepatocytes, and extensive inflammatory cell infiltration were observed in hepatic tissue samples collected from the control group. However, these findings were less pronounced in the group receiving MK615. At the end of the clinical study, serum ALT and AST levels were significantly decreased compared with pre-intake baseline levels from 103.5 ± 58.8 IU/L to 71.8 ± 39.3 IU/L (P < 0.05) and from 93.5 ± 55.6 IU/L to 65.5 ± 34.8 IU/L (P < 0.05), respectively. A reduction of ≥ 30% from the pre-study baseline ALT level was observed in 26 (45%) of the 58 patients, while 25 (43%) patients exhibited similar AST level reductions. The chronic hepatitis C group exhibited significant ALT and AST level reductions from 93.4 ± 51.1 IU/L to 64.6 ± 35.1 IU/L (P < 0.05) and from 94.2 ± 55.5 IU/L to 67.2 ± 35.6 IU/L (P < 0.05), respectively. A reduction of ≥ 30% from the pre-study baseline ALT level was observed in 20 (50%) of the 40 patients. ALT levels in both the combined ursodeoxycholic acid (UDCA) treatment and the UDCA uncombined groups were significantly lower after Misatol ME administration. MK615 protected hepatocytes from D-GalN-induced cytotoxicity in rats. Misatol ME decreased elevated ALT and AST levels in patients with liver disorders. CONCLUSION: These results suggest that MK615 and Misatol ME are promising hepatoprotective agents for patients with liver disorders.


Assuntos
Fígado Gorduroso/tratamento farmacológico , Hepatite C/tratamento farmacológico , Hepatite Autoimune/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Prunus , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Feminino , Galactosamina/efeitos adversos , Hepatite C/metabolismo , Hepatite C/patologia , Hepatite Autoimune/metabolismo , Hepatite Autoimune/patologia , Humanos , Fígado/enzimologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Ratos , Ratos Wistar , Resultado do Tratamento
19.
Med Hypotheses ; 79(4): 452-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22800803

RESUMO

Periodontitis is a major chronic inflammatory disease associated with increased production of numerous proinflammatory cytokines, which leads to the destruction of the periodontal tissue and ultimately loss of teeth. Periodontitis has powerful and multiple influences on the occurrence and severity of systemic conditions and diseases, such as diabetes mellitus, cardiovascular disease and respiratory disease. Meanwhile, diabetes is associated with increased prevalence, severity and progression of periodontal disease. There is also abundant evidence showing that diabetes plays important etiological roles in periodontitis. High mobility group box 1 (HMGB1) was recently identified as a lethal mediator of severe sepsis and comprises a group of intracellular proteins that function as inflammatory cytokines when released into the extracellular milieu. From a clinical perspective, extracellular HMGB1 can cause multiple organ failure and contribute to the pathogenesis of sepsis, rheumatoid arthritis, cardiovascular disease and diabetes. We recently reported that HMGB1 expression in periodontal tissues was elevated in patients with severe periodontitis. In addition, the receptor for advanced glycation end-products (RAGE), a receptor for HMGB1, was strongly expressed in gingival tissues obtained from patients with type 2 diabetes and periodontitis compared with systemically healthy patients with chronic periodontitis patients. From these data, we hypothesize that HMGB1 might play a role in the development of diabetes-associated periodontitis.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Proteína HMGB1/metabolismo , Doenças Periodontais/complicações , Doenças Periodontais/metabolismo , Linhagem Celular , Citocinas/metabolismo , Células Epiteliais/metabolismo , Gengiva/metabolismo , Humanos , Modelos Biológicos , Fatores de Risco , Transdução de Sinais
20.
Phytother Res ; 26(6): 833-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22076920

RESUMO

The Japanese apricot, a commonly consumed food called 'Ume' in Japan, has been used for a traditional Japanese medicine for centuries. MK615, an extract of compounds from 'Ume', has strong antitumorigenic and antiinflammatory effects including the induction of apoptosis and autophagy, and inhibition of cytokine production mediated via the inhibition of MAPKs signaling including ERK-1/2, JNK and p38MAPK. The inhibitor of DNA binding 1 (Id-1), a basic helix-loop-helix (bHLH) transcription factor family, is essential for DNA binding and the transcriptional regulation of various proteins that play important roles in the development, progression and invasion of tumors. In melanoma, Id-1 is constitutively expressed in the late and early stages, suggesting it as a therapeutic target in patients with melanoma. This study reports that MK615 profoundly reduced both the mRNA- and protein expression levels of Id-1 and inhibited cell growth in A375 melanoma cells. MK615 markedly inhibited the phosphorylation of ERK1/2, which is associated with Id-1 protein expression in A375 cells. Id-1-specific RNAi induced the death of A375 cells. Moreover, the expression of Bcl-2 was decreased by both MK615 and Id-1-specific RNAi in A375 cells. The results suggest that MK615 is a potential therapeutic agent for treating malignant melanoma.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteína 1 Inibidora de Diferenciação/metabolismo , Sistema de Sinalização das MAP Quinases , Melanoma/patologia , Extratos Vegetais/farmacologia , Prunus/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Morte Celular , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteína 1 Inibidora de Diferenciação/genética , Melanoma/genética , Melanoma/metabolismo , Fosforilação , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...