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1.
J Biol Chem ; 286(34): 29872-81, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21690090

RESUMO

Dysregulation of liver functions leads to insulin resistance causing type 2 diabetes mellitus and is often found in chronic liver diseases. However, the mechanisms of hepatic dysfunction leading to hepatic metabolic disorder are still poorly understood in chronic liver diseases. The current work investigated the role of hepatitis B virus X protein (HBx) in regulating glucose metabolism. We studied HBx-overexpressing (HBxTg) mice and HBxTg mice lacking inducible nitric oxide synthase (iNOS). Here we show that gene expressions of the key gluconeogenic enzymes were significantly increased in HepG2 cells expressing HBx (HepG2-HBx) and in non-tumor liver tissues of hepatitis B virus patients with high levels of HBx expression. In the liver of HBxTg mice, the expressions of gluconeogenic genes were also elevated, leading to hyperglycemia by increasing hepatic glucose production. However, this effect was insufficient to cause systemic insulin resistance. Importantly, the actions of HBx on hepatic glucose metabolism are thought to be mediated via iNOS signaling, as evidenced by the fact that deficiency of iNOS restored HBx-induced hyperglycemia by suppressing the gene expression of gluconeogenic enzymes. Treatment of HepG2-HBx cells with nitric oxide (NO) caused a significant increase in the expression of gluconeogenic genes, but JNK1 inhibition was completely normalized. Furthermore, hyperactivation of JNK1 in the liver of HBxTg mice was also suppressed in the absence of iNOS, indicating the critical role for JNK in the mutual regulation of HBx- and iNOS-mediated glucose metabolism. These findings establish a novel mechanism of HBx-driven hepatic metabolic disorder that is modulated by iNOS-mediated activation of JNK.


Assuntos
Glucose/biossíntese , Vírus da Hepatite B/metabolismo , Homeostase , Fígado/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Transativadores/metabolismo , Animais , Fatores Relaxantes Dependentes do Endotélio/metabolismo , Fatores Relaxantes Dependentes do Endotélio/farmacologia , Regulação Enzimológica da Expressão Gênica/genética , Gluconeogênese/genética , Glucose/genética , Células Hep G2 , Humanos , Hiperglicemia/genética , Hiperglicemia/metabolismo , Hiperglicemia/virologia , Fígado/virologia , Camundongos , Camundongos Knockout , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacologia , Óxido Nítrico Sintase Tipo II/genética , Transdução de Sinais/genética , Transativadores/genética , Proteínas Virais Reguladoras e Acessórias
2.
Platelets ; 23(5): 376-85, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22309049

RESUMO

This study investigated the inhibitory effects of oligoporin A on platelet aggregation and the mechanism of its action on downstream signaling molecules. Oligoporin A was isolated from the fruiting bodies of Oligoporus tephroleucus (Polyporaceae). The anti-platelet activities of oligoporin A were studied using rat platelets. The effects of oligoporin A on intracellular Ca(2+) mobilization, ATP release, production of the cyclic nucleotides cAMP and cGMP, extracellular signal-regulated kinase (ERK) 2 phosphorylation, and fibrinogen binding to active integrin α(II)(b)ß(3) were assessed. Oligoporin A, but not oligoporins B and C, inhibited collagen-induced platelet aggregation in a concentration-dependent manner. Interestingly, oligoporin A did not affect ADP- and thrombin-induced platelet aggregations, which act on different types of membrane receptors. Granule secretion analysis demonstrated that oligoporin A significantly and dose-dependently reduced collagen-induced ATP release and intracellular Ca(2+) mobilization. Additionally, oligoporin A induced the dynamic increase in cAMP and cGMP. Increased cGMP production was further confirmed by the simultaneous production of nitric oxide. Pretreatment with oligoporin A significantly blocked collagen-induced ERK2 phosphorylation. Finally, oligoporin A vaguely diminished the binding of fibrinogen to its cognate receptor, integrin α(II)(b)ß(3). The results indicate that oligoporin A inhibits only collagen-induced platelet aggregation mediated through the modulation of downstream signaling molecules. Oligoporin A may be beneficial against cardiovascular disease provoked by aberrant platelet activation.


Assuntos
Plaquetas/efeitos dos fármacos , AMP Cíclico/sangue , GMP Cíclico/sangue , MAP Quinases Reguladas por Sinal Extracelular/sangue , Glucosídeos/farmacologia , Triterpenos/farmacologia , Difosfato de Adenosina/sangue , Difosfato de Adenosina/farmacologia , Animais , Plaquetas/enzimologia , Plaquetas/metabolismo , Cálcio/sangue , Fibrinogênio/farmacologia , Glucosídeos/sangue , Humanos , Masculino , Fosforilação , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Triterpenos/sangue
3.
Phytother Res ; 25(11): 1596-603, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21394810

RESUMO

Phellinus baumii is a mushroom that has been used as folk medicine against various diseases and is reported to have antidiabetic, anticancer, antioxidant, antiinflammatory and antihypertensive activities. However, information on the effects of P. baumii extract in platelet function is limited. Therefore, the aim of this study was to examine the impact of a P. baumii methanol extract (PBME) on platelet activation and to investigate the mechanism behind its antiplatelet activity. PBME effects on agonist-induced platelet aggregation, granule secretion, [Ca²âº](i) mobilization, α(IIb) ß3 activation, cyclic AMP release and mitogen-activated protein kinase (MAPK) phosphorylations were studied using rat platelets. PBME dose-dependently inhibited collagen, thrombin and ADP-induced platelet aggregation with an IC50 of 51.0 ± 2.4, 54.0 ± 2.1 and 53.0 ± 4.3 µg/mL, respectively. Likewise, thrombin-induced [Ca²âº](i) and collagen-activated ATP secretions were suppressed in PBME treated platelets. Aggregation and ATP secretion were also markedly attenuated by PBME alone or in combination with PP2 (Src inhibitor) and U-73122 (PLC inhibitor) in collagen-stimulated platelets. Besides, PBME treatment elevated basal cyclic AMP levels and inhibited collagen-induced integrin-α(IIb) ß3 activation. Moreover, PBME attenuated extracellular-signal-regulated protein kinase 2 (ERK2) and c-Jun N-terminal kinase 1 (JNK1) phosphorylations. Further PD98059 (ERK inhibitor) and SP60025 (JNK inhibitor) reduced collagen-induced platelet aggregation and ATP secretion. In conclusion, the observed PBME antiplatelet activity may be mediated by activation of cyclic AMP and inhibition of ERK2 and JNK1 phosphorylations. Finally, these data suggest that PBME may have therapeutic potential for the treatment of cardiovascular diseases that involve aberrant platelet function.


Assuntos
Basidiomycota/química , Produtos Biológicos/farmacologia , Plaquetas/efeitos dos fármacos , AMP Cíclico/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Agaricales/química , Animais , Colágeno/antagonistas & inibidores , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley , Trombina/antagonistas & inibidores
4.
J Neurochem ; 114(1): 39-50, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20345759

RESUMO

Reactive oxygen species (ROS) actively participate in microglia-mediated pathogenesis as pro-inflammatory molecules. However, little is known about the involvement of specific antioxidants in maintaining the microglial oxidative balance. We demonstrate that microglial peroxiredoxin (Prx) 5 expression is up-regulated by lipopolysaccharide (LPS) through activation of the ROS-sensitive signaling pathway and is involved in attenuation of both microglial activation and nitric oxide (NO) generation. Unlike in stimulation of oxidative insults with paraquat and hydrogen peroxide, Prx V expression is highly sensitive to LPS-stimulation in microglia. Reduction of ROS level by treatment with either NADPH oxidase inhibitor or antioxidant ablates LPS-mediated Prx V up-regulation in BV-2 microglial cells and is closely associated with the activation of the c-jun N-terminal kinase (JNK) signaling pathway. This suggests the involvement of ROS/JNK signaling in LPS-mediated Prx V induction. Furthermore, NO induces Prx V up-regulation that is ablated by the addition of inducible nitric oxide synthase inhibitor or deleted mutation of inducible nitric oxide synthase in LPS-stimulated microglia. Therefore, these results suggest that Prx V is induced by cooperative action among the ROS, RNS, and JNK signaling cascades. Interestingly, knockdown of Prx V expression causes the acceleration of microglia activation, including augmented ROS generation and JNK-dependent NO production. In summary, we demonstrate that Prx V plays a key role in the microglial activation process through modulation of the balance between ROS/NO generation and the corresponding JNK cascade activation.


Assuntos
Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Microglia/metabolismo , Óxido Nítrico/biossíntese , Peroxirredoxinas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Técnicas de Silenciamento de Genes , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Mutação , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/fisiologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/genética , Oxirredução , Peroxirredoxinas/biossíntese , Peroxirredoxinas/genética , Espécies Reativas de Nitrogênio/metabolismo , Transdução de Sinais , Regulação para Cima
5.
Eur J Pharmacol ; 584(2-3): 361-7, 2008 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-18313047

RESUMO

This study was designed to investigate the effect of davallialactone, which was isolated from the mushroom Inonotus xeranticus, on platelet aggregation induced by collagen, thrombin and ADP. We found that davallialactone dose-dependently inhibited platelet aggregation that was stimulated either by collagen (2.5 microg/ml), a potent ligand of integrin alpha2beta1 and glycoprotein VI, or by thrombin (0.1U/ml), a potent agonist of the protease-activated receptors (PARs) PAR1 and PAR3. In addition, davallialactone inhibited platelet aggregation induced by ADP, an agonist of P2Y receptor. To understand the mechanism of anti-platelet activity, we determined whether davallialactone affected the downstream signaling in collagen-activated platelets. Using the fura-2/AM fluorometric assay, we found that davallialactone dose-dependently inhibited intracellular calcium concentration levels ([Ca2+]i). Moreover, davallialactone inhibited the phosphorylation of extracellular signal-regulated protein kinase (ERK)-2 and p38 mitogen-activated protein kinase (MAPK), in a dose-dependent manner. The tyrosine phosphorylation of 60 and 85kDa proteins, which were activated by collagen, were differentially inhibited by davallialactone. Taken together, these data suggest that davallialactone may have potential anti-platelet aggregation activity via suppression of intracellular downstream signaling pathways.


Assuntos
Plaquetas/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Lactonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Difosfato de Adenosina/metabolismo , Animais , Plaquetas/enzimologia , Plaquetas/metabolismo , Colágeno/metabolismo , Relação Dose-Resposta a Droga , Fosforilação , Fosfotirosina/metabolismo , Ratos , Trombina/metabolismo
6.
Phytother Res ; 22(10): 1389-95, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18688813

RESUMO

Aloe species are traditionally prescribed for hypertension, burning, and rheumatoid arthritis. To elucidate the mechanism of the antihypertensive and anti-inflammatory activities of this herb, the ethanol fraction from A. saponaria Haw. was evaluated for antioxidative activity using xanthine-xanthine oxidase (XO) assay, 2,2-Diphenyl-lpicrylhydrazyl radical (DPPH) assay, lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cell, and antinociceptive activity using a tail-flick assay and hind paw pressure assay in cisplatin-treated hyperalgesic rats. The ethanol fraction displayed potent antioxidative activities in XO assay. In addition, ethanol fractions showed potent scavenging effects in DPPH assay. We next examined whether ethanol fractions showed anti-inflammatory activities. Ethanol fractions significantly suppressed NO production from LPS-activated RAW264.7 cells. As expected, ethanol fractions dose-dependently inhibited the messenger RNA expression of inducible NO synthase (iNOS). Moreover, ethanol fractions potently suppressed the expression of cycloxygenase (COX)-2 and granulocyte-macrophage colony-stimulating factor (GM-CSF), which are stimulated by LPS in RAW264.7 cells. In addition, ethanol fractions significantly blocked cisplatin-induced hyperalgesia using tail-flick assay and hind paw pressure test in rats. Taken altogether, ethanol extracts of aloe may be useful as a functional food or as a drug against reactive oxygen species (ROS) mediated diseases.


Assuntos
Aloe/química , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Compostos de Bifenilo , Linhagem Celular , Cisplatino/farmacologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Etanol/química , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Camundongos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Picratos/química , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Xantina Oxidase/metabolismo
7.
Pharmazie ; 62(6): 453-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17663194

RESUMO

Suaeda asparagoides Miq. (Chenopodiaceae: S. asparagoides) is a salt-marsh plant that has long been prescribed in traditional Oriental medicine for the treatment of hypertension and hepatitis. In order to elucidate the pharmacological mechanisms of the herb, we conducted an examination of the anti-oxidative and anti-inflammatory properties of solvent-extracts of S. asparagoides. All of the solvent fractions showed potent anti-oxidative effects, as assessed using a radical generation assay system (xanthine oxidase assay) and an electron-donating activity system (DPPH [2,2-diphenyl-l-picrylhydrazyl radical] assay), with IC50 values ranging from 9 to 42 microg/ml. In agreement with this pattern, the total phenolic contents were widely distributed in the various solvent fractions, and ranged from 36.5 to 50.3 mg/g of dry weight. All of the solvent fractions significantly suppressed NO production in RAW264.7 cells induced by lipopolysaccharide (LPS, 0.1 microg/ml) and of the fractions, only the chloroform (CHC) fraction completely blocked the expression of inducible NO synthase (iNOS). Additionally, the hexane (HEX) and CHC fractions suppressed the mRNA expression of granulocyte/macrophage colony-stimulating factor (GM-CSF) and monocyte chemoattractant protein 1 (MCP-1), respectively, in the LPS-stimulated RAW264.7 cells. Therefore, these results suggest that the pharmacological action of S. asparagoides is due to its potent anti-oxidative effects and anti-inflammatory effects, and that therefore it can be applied to other diseases caused by oxidative stress and inflammation, such as cardiovascular diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Chenopodiaceae/química , Animais , Compostos de Bifenilo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quimiocinas/biossíntese , Citocinas/biossíntese , Inibidores Enzimáticos/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Fenóis/análise , Picratos/química , Extratos Vegetais/farmacologia , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Solventes , Sais de Tetrazólio , Tiazóis , Xantina Oxidase/antagonistas & inibidores
8.
Ann Rehabil Med ; 41(1): 16-24, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28289631

RESUMO

OBJECTIVE: To evaluate effects of caregiver's education program on their satisfaction, as well as patient functional recovery, performed in addition to daily conventional rehabilitation treatment. METHODS: Three hundred eleven subjects diagnosed with first-onset stroke and transferred to the Department of Physical Medicine and Rehabilitation of Inha University Hospital were surveyed. In 2015, caregivers attended an education program for acute and subacute stroke patients. Patients who received an additional rehabilitation therapy were assigned to the experimental group (n=81), whereas the control group (n=100) consisted of transfer cases in 2014 with only conventional treatment. The experimental group was classified by severity using the Korean version of the National Institutes of Health Stroke Scale (K-NIHSS), which was administered to all 181 subjects, in addition to, the Korean version of the Mini Mental Status Examination (K-MMSE), a Modified Barthel Index (K-MBI), and the Berg Balance Scale (K-BBS). Caregiver satisfaction and burden before and after education programs were assessed using the Canadian Occupational Performance Measure (COPM), as well as family burden and caregiver burnout scales. RESULTS: No significant intergroup difference was observed between initial K-NIHSS, K-MMSE, K-BBS, K-MBI scores, and times from admission to transfer. Those with moderate or severe strokes under the experimental condition showed a more significant improvement than the control group as determined by the K-NIHSS and K-BBS, as well as tendential K-MMSE and K-MBI score increases. Satisfaction was significantly greater for family members and formal caregivers of patients with strokes of moderate severity in the experimental group. CONCLUSION: The caregiver's education program for stroke subjects had a positive outcome on patients' functional improvement and caregiver satisfaction. The authors believe that the additional rehabilitation therapy with the education program aids patients to achieve functional improvements for an optimal return to social life.

9.
J Pharm Pharmacol ; 58(6): 867-70, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16734989

RESUMO

This study was designed to investigate the effect of surfactin C, which is derived from Bacillus subtilis, on platelet aggregation and homotypic leucocyte aggregation. Surfactin C strongly and dose-dependently inhibited platelet aggregation, which was stimulated both by thrombin (0.1 U mL(-1)), a potent agonist that activates the G protein-coupled protease receptor, and by collagen (5 microg mL(-1)), a potent ligand that activates alpha(IIb)beta(3) with IC50 values (concentration inhibiting platelet aggregation by 50%) of 10.9 and 17.0 microM, respectively. Moreover, surfactin C significantly suppressed the intracellular Ca(2+) mobilization in thrombin-activated platelets. Surfactin C, however, did not affect various integrin-mediated U937 cell aggregation, implying that the anti-platelet activity of surfactin C was not due to its detergent effect but by its action on the downstream signalling pathway. Therefore, the results suggest that surfactin C may have a beneficial therapeutic effect on aberrant platelet aggregation-mediated cardiovascular diseases.


Assuntos
Peptídeos Cíclicos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Animais , Cálcio/metabolismo , Colágeno/farmacologia , Relação Dose-Resposta a Droga , Lipopeptídeos , Fosfolipases A/fisiologia , Ratos , Trombina/farmacologia
10.
J Pharm Pharmacol ; 58(1): 113-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16393471

RESUMO

Opuntia humifusa Raf. (O. humifusa Raf.) is a member of the Cactaceae family. To determine the antioxidative and anti-inflammatory effects of this herb, various solvent fractions (methanol, hexane, chloroform, ethyl acetate, butanol, and water) prepared from the leaves of cacti were tested using DPPH (2,2-diphenyl-l-picrylhydrazyl radical) and xanthine oxidase assays, and nitric oxide (NO)-producing macrophage cells. We found that O. humifusa Raf. displayed potent antioxidative and anti-inflammatory activity. Thus, all solvent fractions, except for the water layer, showed potent scavenging effects. The scavenging effect of the ethyl acetate fraction was higher than that of the other fractions, with IC50 values of 3.6 and 48.2 microg mL(-1). According to activity-guided fractionation, one of the active radical scavenging principles in the ethyl acetate fraction was found to be quercetin. In contrast, only two fractions (chloroform and ethyl acetate) significantly suppressed nitric oxide production from the lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, chloroform and ethyl acetate fractions significantly blocked the expression of inducible nitric oxide synthetase (iNOS) and interleukin-6 (IL-6) from the RAW264.7 cells stimulated by LPS. Moreover, ethyl acetate fractions significantly blocked the expression of IL-1beta from the RAW264.7 cells stimulated by LPS. Therefore, the results suggested that O. humifusa Raf. may modulate radical-induced toxicity via both direct scavenging activity and the inhibition of reactive species generation, and the modulation of the expression of inflammatory cytokines. Finally, O. humifusa Raf. may be useful as a functional food or drug against reactive species-mediated disease.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Opuntia/química , Compostos de Bifenilo/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Hidrazinas/metabolismo , Interleucina-1/genética , Interleucina-1/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Picratos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Raízes de Plantas/química , RNA Mensageiro/metabolismo , Xantina Oxidase/metabolismo
11.
FEBS Lett ; 579(21): 4897-902, 2005 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-16109412

RESUMO

Reactive oxygen species (ROS) were generated in all oxygen-utilizing organisms. Peroxiredoxin II (Prx II) as one of antioxidant enzymes may play a protective role against the oxidative damage caused by ROS. In order to define the role of Prx II in organismal aging, we evaluated cellular senescence in Prx II(-/-) mouse embryonic fibroblast (MEF). As compared to wild type MEF, cellular senescence was accelerated in Prx II(-/-) MEF. Senescence-associated (SA)-beta-galactosidase (Gal)-positive cell formation was about 30% higher in Prx II(-/-) MEF. N-Acetyl-l-cysteine (NAC) treatment attenuated SA-beta-Gal-positive cell formation. Prx II(-/-) MEF exhibited the higher G2/M (41%) and lower S (1.6%) phase cells as compared to 24% and 7.3% [corrected] in wild type MEF, respectively. A high increase in the p16 and a slight increase in the p21 and p53 levels were detected in PrxII(-/-) MEF cells. The cellular senescence of Prx II(-/-) MEF was correlated with the organismal aging of Prx II(-/-) mouse skin. While extracellular signal-regulated kinase (ERK) and p38 activation was detected in Prx II(-/-) MEF, ERK and c-Jun N-terminal kinase (JNK) activation was detected in Prx II(-/-) skin. These results suggest that Prx II may function as an enzymatic antioxidant to prevent cellular senescence and skin aging.


Assuntos
Senescência Celular , Peroxidases/metabolismo , Acetilcisteína/metabolismo , Envelhecimento/fisiologia , Animais , Ciclo Celular/fisiologia , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/metabolismo , Peróxido de Hidrogênio/metabolismo , Camundongos , Camundongos Knockout , Oxidantes/metabolismo , Peroxidases/genética , Peroxirredoxinas , Espécies Reativas de Oxigênio/metabolismo
12.
Exp Mol Med ; 36(6): 588-93, 2004 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-15675043

RESUMO

Hepatitis C virus (HCV) is a major causative agent in liver disease. In order to investigate if Korean type HCV core protein and its related mutants, S99Q and S1161, are cytopathic to liver, three types of transgenic mice were established. The expression of transgenes was confirmed by HCV specific RT-PCR and Western immunoblotting. The livers of all wild type core and S1161 transgenic lineages remained largely histologically normal. However, the livers of the S99Q transgenic mice showed significant high level of cell dysplasia associated with the transgene expression in hepatocytes largely located around the central veins by in situ hybridization analysis. In conclusion, the mutant HCV core protein at S99Q may contribute to the progress of HCV induced liver disease.


Assuntos
Hepatite C/patologia , Hepatite Viral Animal/patologia , Fígado/virologia , Proteínas do Core Viral/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Expressão Gênica , Vetores Genéticos/genética , Hepatite C/virologia , Hepatite Viral Animal/virologia , Hepatócitos/patologia , Hepatócitos/virologia , Fígado/patologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Mutação/genética , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Transgenes , Proteínas do Core Viral/análise , Proteínas do Core Viral/metabolismo
13.
J Vet Sci ; 3(3): 179-84, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12514329

RESUMO

It is now well established that several G protein- coupled receptors can signal without agonist stimulation (constitutive receptors). Inverse agonists have been shown to inhibit the activity of such constitutive G protein-coupled receptor signaling. Agonist activation of the G(i/o)-coupled peripheral cannabinoid receptor CB2 normally inhibits adenylyl cyclase type V and stimulates adenylyl cyclase type II. Using transfected COS cells, we show here that application of SR144528, an inverse agonist of CB2, leads to a reverse action (stimulation of adenylyl cyclase V and inhibition of adenylyl cyclase II). This inverse agonism of SR144528 is dependent on the temperature, as well as on the concentration of the cDNA of CB2 transfected. Pertussis toxin blocked the regulation of adenylyl cyclase activity by SR 144528.


Assuntos
Canfanos/farmacologia , Pirazóis/farmacologia , Receptor CB2 de Canabinoide , Receptores de Droga/antagonistas & inibidores , Inibidores de Adenilil Ciclases , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Animais , Ligação Competitiva , Células COS , Canfanos/metabolismo , Canabinoides/metabolismo , Chlorocebus aethiops , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Pirazóis/metabolismo , Ratos , Receptores de Canabinoides , Receptores de Droga/agonistas , Receptores de Droga/genética , Receptores de Droga/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transfecção
14.
J Vet Sci ; 4(2): 151-4, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14610368

RESUMO

The present study was carried out to investigate the effects of biomedicinal agents on Ca2+, P and alkaline phosphatase (ALP) levels in ovariectomized rats. Rats were ovariectomized bilaterally and were fed up with Ca2+ and P-free diet during 8(9,10) weeks to induce osteoporosis. Osteoporosis was determined by the extent of bone density and by lowering the concentrations of serum Ca2+, P and ALP activity every week. Rats in antler, safflower, ipriflavon, or co-administrated with estrogen groups were administrated with feed supplement for 5 weeks to elucidate the protective and therapeutic effects against osteoporosis. The bone tissue was examined with electron microscope to determine the effects of each treatment on osteoporosis. 1. The levels of serum Ca2+ and P in osteoporosis-induced rats, administrated with antler, ipriflavon and estrogen groups, were little higher than those of control rats. However, the levels of serum Ca and P in ovariectomized rats were significantly higher than those of control group (p<0.05). 2. The activities of serum ALP in osteoporosis-induced rats, administrated with antler extract, safflower, ipriflavon, or co-administrated with estrogen, were little increased in comparing with those of control group, but were significantly decreased in with combination of estrogen for 5 weeks. However, The connections were interrupted and the bone matrix was destroyed in the osteoporosis-induced rats. 3. The inter-trabecular connections were examined under electron microscope. The connections were well maintained and bone loss was without in the administration with antler, safflower, and ipriflavon with combination of estrogen for 5 weeks. However, The connections were interrupted and the bone matrix was destroyed in the osteoporosis-induced rats.


Assuntos
Fosfatase Alcalina/sangue , Densidade Óssea/fisiologia , Cálcio/sangue , Osteoporose/sangue , Fosfatos/sangue , Animais , Chifres de Veado , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Isoflavonas/administração & dosagem , Isoflavonas/farmacologia , Osteoporose/enzimologia , Osteoporose/prevenção & controle , Ovariectomia , Fitoterapia , Ratos , Óleo de Cártamo/administração & dosagem , Óleo de Cártamo/uso terapêutico , Extratos de Tecidos/administração & dosagem , Extratos de Tecidos/uso terapêutico
15.
J Ginseng Res ; 36(3): 263-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23717127

RESUMO

Korean red ginseng has shown therapeutic effects for a number of disease conditions. However, little is known about the antiinflammatory effect of Korean red ginseng saponin fraction (RGSF) in vitro and in vivo. Therefore, in this study, we showed that RGSF containing 20(S)-protopanaxadiol type saponins inhibited nitric oxide production and attenuated the release of tumor necrotic factor (TNF)-α, interleukin (IL)-6, granulocyte monocyte colony stimulating factor (GMCSF), and macrophage chemo-attractant protein-1 in lipopolysaccharide (LPS) stimulated murine macrophage RAW264.7 cells. Moreover, RGSF down-regulated the mRNA expressions of inducible nitric oxide synthase, cyclooxyginase-2, IL-1ß, TNF-α, GMCSF, and IL-6. Furthermore, RGSF reduced the level of TNF-α in the serum and protected mice against LPS mediated endotoxic shock. In conclusion, these results indicated that ginsenosides from RGSF and their metabolites could be potential sources of therapeutic agents against inflammation.

16.
J Nat Med ; 66(1): 49-54, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21656334

RESUMO

Mushrooms are valuable sources of biologically active compounds possessing anticancer, antiplatelet, and anti-inflammatory properties. Phellinus baumii is a mushroom used in folk medicine for a variety of human diseases. However, its potential anti-inflammatory effect has remained unclear. Therefore, we studied the effect of P. baumii ethyl acetate extract (PBEAE) on inflammatory mediator and proinflammatory cytokine protein and/or mRNA expression levels using the nitric oxide (NO) assay, enzyme immunoassay (EIA), western blot, and reverse transcription polymerase chain reaction (RT-PCR) in lipopolysaccharide (LPS)-stimulated macrophage like RAW264.7 cells. PBEAE markedly inhibited NO generation and prostaglandin E(2) (PGE(2)) synthesis in a concentration-dependent pattern without any cytotoxic effect at the concentration range used. PBEAE also suppressed inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression. In addition, LPS-induced iNOS and COX-2 mRNA expression levels were dose-dependently inhibited by PBEAE pretreatment. Furthermore, PBEAE attenuated the mRNA expression levels of proinflammatory cytokines, specifically interleukin (IL)-1ß, IL-6, and granulocyte macrophage colony-stimulating factor (GM-CSF), in a concentration-dependent fashion. Our study suggests that P. baumii might exhibit anti-inflammatory properties by downregulating proinflammatory mediators. Thus, further study on compounds isolated from PBEAE is warranted to investigate the associated molecular mechanisms and identify the potential therapeutic targets.


Assuntos
Agaricales , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Acetatos/química , Agaricales/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Western Blotting , Linhagem Celular , Ciclo-Oxigenase 2/genética , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Técnicas Imunoenzimáticas , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Macrófagos/enzimologia , Macrófagos/imunologia , Medicina Tradicional , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Solventes/química
17.
Eur J Pharmacol ; 627(1-3): 85-91, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19913011

RESUMO

Platelets, though anucleated, possess several transcription factors, including NF-kappaB, that exert non-genomic functions regulating platelet activation. Since platelets have not only been recognized as central players of homeostasis, but also participated in pathological conditions such as thrombosis, atherosclerosis, and inflammation, we examined rat platelet NF-kappaB expression and evaluated the effects of anti-inflammatory drug BAY 11-7082, an inhibitor of NF-kappaB activation, in platelet physiology. Western blotting revealed that rat platelets express NF-kappaB. BAY 11-7082, dose dependently, inhibited collagen- or thrombin-induced-platelet aggregation. ATP release, TXB(2) formation, P-selectin expression, and intercellular Ca(2+) concentration activated by collagen were reduced in BAY 11-7082-treated platelets. BAY 11-7082 elevated intracellular levels of cAMP, but not cGMP, and its co-incubation with cAMP-activating agent (forskolin) or its hydrolyzing enzyme inhibitor (3-isobutyl-1-methylxanthine, IBMX), synergistically inhibited collagen-induced-platelet aggregation. In addition, vasodilator-stimulated-phosphoprotein (VASP) phosphorylation was enhanced in BAY 11-7082-treated platelets, which was partially inhibited by a protein kinase A (PKA) inhibitor, H-89. Moreover, while p38 mitogen-activated protein kinase (MAPK) was not affected, BAY 11-7082 attenuated c-Jun N-terminal kinase 1 (JNK1) and extracellular-signal-regulated protein kinase 2 (ERK2) phosphorylations. In conclusion, BAY 11-7082 inhibits platelet activation, granule secretion, and aggregation, and that this effect is mediated by inhibition of JNK1 and ERK2 phosphorylations, and partially by stimulation of cAMP-dependent PKA VASP phosphorylation. The ability of BAY 11-7082 to inhibit platelet function might be relevant in cases involving aberrant platelet activation where the drug is considered as anti-atherothrombosis, and anti-inflammatory therapy.


Assuntos
Anti-Inflamatórios/farmacologia , Moléculas de Adesão Celular/metabolismo , AMP Cíclico/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Nitrilas/farmacologia , Fosfoproteínas/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Sulfonas/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Cálcio/metabolismo , Colágeno/farmacologia , AMP Cíclico/biossíntese , GMP Cíclico/biossíntese , GMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , NF-kappa B/metabolismo , Selectina-P/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Trombina/farmacologia , Tromboxano A2/biossíntese
18.
Artigo em Inglês | MEDLINE | ID: mdl-19964000

RESUMO

A device which integrates existing intravenous continuous glucose monitors and infusion pumps into a central hub for automated intravenous intensive insulin therapy, targeting non-diabetic critically-ill patients is presented. Additionally, a fuzzy logic based controller that is capable of automatically making closed-loop decisions to achieve tight glycemic control between a euglycemic range of 90 to 120 mg/dl is presented. Initial bench top testing shows a significant improvement in glycemic control with fuzzy logic control when compared to manual infusion protocols currently used in hospitals; future animal testing will be performed to verify these results in vivo.


Assuntos
Análise Química do Sangue/métodos , Glicemia/metabolismo , Monitorização Fisiológica/métodos , Automação , Engenharia Biomédica , Glicemia/análise , Sistemas de Apoio a Decisões Clínicas , Lógica Fuzzy , Humanos , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Sistemas de Infusão de Insulina , Unidades de Terapia Intensiva , Salas Cirúrgicas
19.
Biol Pharm Bull ; 31(9): 1711-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18758064

RESUMO

The importance of microglial reactive oxygen species (ROS) signaling in neuroinflammatory processes has been well demonstrated; however, relatively little is known regarding the related mechanisms underlying these processes. Here, we show that ROS-dependent signal pathways that govern microglial phagocytosis are highly dependent upon nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) activation. Specifically, phagocytosis was greatly reduced by both antioxidant and Nox inhibitor treatments in lipopolysaccharide (LPS)-stimulated BV-2 microglia. Additionally, there was a marked reduction in intracellular ROS content. These results suggest that Nox is the main ROS source for LPS-induced microglial phagocytosis. More decisive evidence for the involvement of ROS in phagocytosis was obtained from an examination of phosphatidyl inositol 3-kinase (PI3-K) and p38 mitogen-activated protein kinase (MAPK) signal pathway activation under reduced ROS levels. These two kinases were activated by LPS treatment and inhibited by ROS neutralization and Nox inhibition. We conclude that microglial phagocytosis requires ROS-dependent PI3-K and p38 MAPK activation and that Nox-derived ROS functions as an upstream regulator of both PI3-K and p38 MAPK. These findings will provide a fundamental basis for a therapeutic modality in inflammation-mediated neurodiseases.


Assuntos
Lipopolissacarídeos/farmacologia , Microglia/efeitos dos fármacos , NADPH Oxidases/metabolismo , Fagocitose/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Western Blotting , Linhagem Celular , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Microscopia de Fluorescência , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
20.
Biol Pharm Bull ; 31(5): 820-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18451500

RESUMO

Imbalance between oxidative stress and antioxidative defence system is generally known as one of mechanisms causing an oxidative stress-medieated neuropathogenesis. Peroxiredoxins (Prxs), a family of antioxidative enzymes neutralizing cellular hydroperoxides, was characterized recently, but their distributions and roles have not been resolved clearly or controversial in the central nervous system, Therefore, the present study was carried out to determine the specific cell types that express Prx I in the mouse brain and primary neural cells, and to examine its antioxidative role in the preferential cell types. Immunohistochemical reactivity for Prx I was detected dominantly in oligodendrocytes and rarely in microglia, whereas strong and specific immunoreactivity for Prx I was observed exclusively in microglia of primary neural cell culture. Further evidences for Prx I specificity were its relatively high expression in BV-2 microglial cells and its upregulated expression in microglia after lipopolysaccharide (LPS) stimulation. These results imply that Prx I can be used as an indicator of microglial activation. Inhibition of p38 MAPK ablated LPS-mediated Prx I upregulation and sensitized the microglia to H(2)O(2)-mediated cell death. These findings indicate that Prx I function as a scavenger for H(2)O(2) generated during microglial activation. The results of this study will help in unraveling the neuropathologic roles of the six Prx isoforms in neural function.


Assuntos
Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/farmacologia , Microglia/fisiologia , Peroxirredoxinas/metabolismo , Animais , Western Blotting , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Regulação para Cima/efeitos dos fármacos
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