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1.
Int J Mol Sci ; 17(10)2016 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-27754362

RESUMO

In our previous work, the ethanolic extract of Panax ginseng C. A. Meyer was successively partitioned using supercritical carbon dioxide at pressures in series to yield residue (R), F1, F2, and F3 fractions. Among them, F3 contained the highest deglycosylated ginsenosides and exerted the strongest antioxidant and anti-inflammatory activities. The aim of this study was to investigate the protective effects of P. ginseng fractions against cellular oxidative stress induced by hydrogen peroxide (H2O2). Viability of adult retinal pigment epithelium-19 (ARPE-19) cells was examined after treatments of different concentrations of fractions followed by exposure to H2O2. Oxidative levels (malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reactive oxygen species (ROS)) and levels of activity of antioxidant enzymes were assessed. Results showed that F3 could dose-dependently protected ARPE-19 cells against oxidative injury induced by H2O2. F3 at a level of 1 mg/mL could restore the cell death induced by H2O2 of up to 60% and could alleviate the increase in cellular oxidation (MDA, 8-OHdG, and ROS) induced by H2O2. Moreover, F3 could restore the activities of antioxidant enzymes suppressed by H2O2. In conclusion, F3 obtained using supercritical carbon dioxide fractionation could significantly increase the antioxidant capacity of P. ginseng extract. The antioxidant capacity was highly correlated with the concentration of F3.


Assuntos
Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Panax/química , Extratos Vegetais/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Antioxidantes/química , Dióxido de Carbono/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico/métodos , Humanos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo
2.
Biochem Biophys Res Commun ; 437(1): 55-61, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23791833

RESUMO

The aim of this study is to investigate the relationship between paraoxonase 1 (PON1) and atherosclerosis-related inflammation. In this study, human hepatoma HepG2 cell line was used as a hepatocyte model to examine the effects of the pro-inflammatory cytokines on PON1 expression. The results showed that IL-6, but not TNF-α and IL-1ß, significantly increased both the function and protein level of PON1; data from real-time RT-PCR analysis revealed that the IL-6-induced PON1 expression occurred at the transcriptional level. Increase of IκB kinase activity and IκB phosphorylation, and reduction of IκB protein level were also observed in IL-6-treated HepG2 cells compared with untreated culture. This event was accompanied by increase of NF-κB-p50 and -p65 nuclear translocation. Moreover, treatment with IL-6 augmented the DNA binding activity of NF-κB. Furthermore, pharmacological inhibition of NF-κB activation by PDTC and BAY 11-7082, markedly suppressed the IL-6-mediated PON1 expression. In addition, IL-6 increased the levels of phosphorylated protein kinase B (PKB, AKT). An AKT inhibitor LY294002 effectively suppressed IKK/IκB/NF-κB signaling and PON1 gene expression induced by IL-6. Our findings demonstrate that IL-6 upregulates PON1 gene expression through an AKT/NF-κB signaling axis in human hepatocyte-derived HepG2 cell line.


Assuntos
Arildialquilfosfatase/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Interleucina-6/farmacologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Arildialquilfosfatase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células Hep G2 , Humanos , Interleucina-1beta/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-21915187

RESUMO

Plectranthus amboinicus (Lour.) Spreng. is a native Labiatae plant of Taiwan. The plants are commonly used in Chinese folk medicine for the treatment of cough, fever, sore throats, mumps, and mosquito bite. The aim of this study was to investigate the analgesic and antiinflammatory properties of the aqueous extract from Plectranthus amboinicus (PA) in vivo and in vitro. PA inhibited pain induced by acetic acid and formalin, and inflammation induced by carrageenan. The anti-inflammatory effect of PA was related to modulating antioxidant enzymes' activities in the liver and decreasing the Malondialdehyde (MDA) level and the production of tumor necrosis factor alpha (TNF-α), and cyclooxygenase2 (COX-2) in edema-paw tissue in mice. In vitro studies show that PA inhibited the proinflammatory mediators in RAW 264.7 cells stimulated with lipopolysaccharide (LPS). PA blocked the degradation of IκB-α and nuclear translocation of NF-κB p65 subunit. Finally, the amount of carvacrol in the aqueous extract of PA was 1.88 mg/g extract. Our findings suggest that PA has analgesic and anti-inflammatory activities. These effects were mediated by inhibiting the proinflammatory mediators through blocking NF-κB activation. Meanwhile, the effects observed in this study provide evidence for folkloric uses of Plectranthus amboinicus (Lour.) Spreng. in relieving pain and inflammation.

4.
Hu Li Za Zhi ; 59(2): 61-71, 2012 Apr.
Artigo em Zh | MEDLINE | ID: mdl-22469893

RESUMO

BACKGROUND: Breast cancer is currently the type of cancer with the highest annual incidence among women in Taiwan, resulting in a median age of death of 57 years. Nevertheless, the proportion of Taiwanese women with a history of mammographic screening is relatively low. The international literature associates participation in mammographic screening with factors such as age, education level, ethnicity, and previous cancer history. Few such studies in Taiwan have addressed a cross-section sample that is representative of the overall population. PURPOSE: The present study investigated factors associated with non-utilization of mammographic screening in women aged between 50 to 69 years in Taiwan. METHODS: This study used secondary data analysis to investigate data obtained from the 2005 National Health Interview Survey in Taiwan. Researchers used logistic regression analysis to evaluate factors associated with mammographic screening in Taiwanese women based on the Andersen behavioral model of health services use. RESULTS: Only 24.3% of the survey population had received mammographic screening. Results of multiple logistic regression analysis indicated non-utilization of mammographic screening is associated with a relatively low education level, being currently employed, a relatively low average monthly salary, having no additional insurance coverage outside the National Health Insurance, having no physical examination history, and having no history of menopausal hormone replacement therapy use. CONCLUSIONS: Hospitals and health units may use findings from the present study to plan mammographic screening programs. Mammography promotional material should consider the needs of women with lower education levels; screening schedules should be coordinated with employers and made convenient for working women; and promotional materials should target women who have never previously received a physical examination. Enhancing the willingness of women to obtain mammography may reduce the threat of breast cancer to the lives of Taiwanese women.


Assuntos
Mamografia/estatística & dados numéricos , Idoso , Feminino , Humanos , Modelos Logísticos , Mamografia/psicologia , Pessoa de Meia-Idade , Taiwan
5.
J Biol Chem ; 285(41): 31755-62, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-20696767

RESUMO

Matriptase, a membrane-tethered serine protease, plays essential roles in epidermal differentiation and barrier function, largely mediated via its activation of prostasin, a glycosylphosphatidylinositol-anchored serine protease. Matriptase activity is tightly regulated by its inhibitor hepatocyte growth factor activator inhibitor-1 (HAI-1) such that free active matriptase is only briefly available to act on its substrates. In the current study we provide evidence for how matriptase activates prostasin under this tight control by HAI-1. When primary human keratinocytes are induced to differentiate in a skin organotypic culture model, both matriptase and prostasin are constitutively activated and then inhibited by HAI-1. These processes also occur in HaCaT human keratinocytes when matriptase activation is induced by exposure of the cells to a pH 6.0 buffer. Using this acid-inducible activation system we demonstrate that prostatin activation is suppressed by matriptase knockdown and by blocking matriptase activation with sodium chloride, suggesting that prostatin activation is dependent on matriptase in this system. Kinetics studies further reveal that the timing of autoactivation of matriptase, prostasin activation, and inhibition of both enzymes by HAI-1 binding are closely correlated. These data suggest that, during epidermal differentiation, the matriptase-prostasin proteolytic cascade is tightly regulated by two mechanisms: 1) prostasin activation temporally coupled to matriptase autoactivation and 2) HAI-1 rapidly inhibiting not only active matriptase but also active prostasin, resulting in an extremely brief window of opportunity for both active matriptase and active prostasin to act on their substrates.


Assuntos
Diferenciação Celular/fisiologia , Epiderme/enzimologia , Queratinócitos/enzimologia , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Serina Endopeptidases/metabolismo , Células 3T3 , Animais , Diferenciação Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Proteínas Secretadas Inibidoras de Proteinases/farmacologia
6.
Complement Ther Med ; 43: 44-48, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30935553

RESUMO

BACKGROUND AND PURPOSE: Fatigue is one of the most prevalent adverse events reported by cancer patients. The aim of this study was to investigate the association between traditional Chinese medicine body constitution (TCMBC) and moderate-to-severe cancer-related fatigue in cancer patients. MATERIALS AND METHODS: A cross-sectional study was conducted on cancer patients recruited from a regional hospital in southern Taiwan. The association between TCMBC, measured using the Constitution in Chinese Medicine Questionnaire (CCMQ) and moderate-to-severe cancer-related fatigue (based on the Taiwanese version of the Brief Fatigue Inventory score ≥ 4) was evaluated using multiple logistic regression analysis. RESULTS: Of the 170 participants, 37 (21.8%) had moderate-to-severe fatigue. Yang-deficiency (adjusted odds ratio [aOR] = 3.55, 95% confidence interval [CI] = 1.50-8.40) and Qi-deficiency (aOR = 2.84, 95% CI = 1.18-6.82) TCMBC were significantly associated with moderate-to-severe cancer-related fatigue. CONCLUSION: TCMBC could be used as a clinical tool to identify cancer patients prone to experience moderate-to-severe cancer-related fatigue, and to provide Chinese medicine practitioners a basis for selecting an appropriate treatment approach based on TCMBC.


Assuntos
Constituição Corporal/fisiologia , Fadiga/tratamento farmacológico , Fadiga/etiologia , Neoplasias/complicações , Estudos Transversais , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Terapias Mente-Corpo/métodos , Prevalência , Qi , Taiwan , Deficiência da Energia Yang/tratamento farmacológico
7.
Eur J Pharmacol ; 590(1-3): 343-54, 2008 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-18590725

RESUMO

Platelet-derived growth factor (PDGF) is released from vascular smooth muscle cells (VSMCs), endothelial cells, or macrophages after percutaneous coronary intervention and is related with neointimal proliferation and restenosis. Berberine is a well-known component of the Chinese herb medicine Huanglian (Coptis chinensis), and is capable of inhibiting growth and endogenous PDGF synthesis in VSMCs after in vitro mechanical injury. We analyzed the effects of berberine on VSMC growth, migration, and signaling events after exogenous PDGF stimulation in vitro in order to mimic a post-angioplasty PDGF shedding condition. Pretreatment of VSMCs with berberine inhibited PDGF-induced proliferation. Berberine significantly suppressed PDGF-stimulated Cyclin D1/D3 and Cyclin-dependent kinase (Cdk) gene expression. Moreover, berberine increased the activity of AMP-activated protein kinase (AMPK), which led to phosphorylation activation of p53 and increased protein levels of the Cdk inhibitor p21(Cip1). Compound C, an AMPK inhibitor, partly but significantly attenuated berberine-elicited growth inhibition. In addition, stimulation of VSMCs with PDGF led to a transient increase in GTP-bound, active form of Ras, Cdc42 and Rac1, as well as VSMC migration. However, pretreatment with berberine significantly inhibited PDGF-induced Ras, Cdc42 and Rac1 activation and cell migration. Co-treatment with farnesyl pyrophosphate and geranylgeranyl pyrophosphate drastically reversed berberine-mediated anti-proliferative and migratory effects in VSMCs. Based on these findings, we conclude that berberine inhibited PDGF-induced VSMC growth via activation of AMPK/p53/p21(Cip1) signaling while inactivating Ras/Rac1/Cyclin D/Cdks and suppressing PDGF-stimulated migration via inhibition of Rac1 and Cdc42. These observations offer a molecular explanation for the anti-proliferative and anti-migratory properties of berberine.


Assuntos
Berberina/farmacologia , Complexos Multienzimáticos/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Quinases Ativadas por AMP , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/análise , Ciclina D3 , Ciclinas/análise , MAP Quinase Quinase 1/metabolismo , Músculo Liso Vascular/citologia , Ratos , Ratos Sprague-Dawley , Proteínas rac1 de Ligação ao GTP/metabolismo
8.
Toxicon ; 52(2): 318-29, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18602939

RESUMO

Honeybee (Apis mellifera) venom (BV) has been reported to exhibit anticancer effects, but its mode of action at the cellular and molecular levels remains largely unknown. We found that honeybee venom induced apoptosis in human melanoma A2058 cells but not in normal skin fibroblast Detroit 551 cells. The BV-induced apoptosis was accompanied by generation of reactive oxygen species and alteration of mitochondrial membrane potential transition. Treatment with antioxidants significantly attenuated BV-induced apoptosis. Although caspase-2 and -3 were slightly activated by BV, inhibitors of caspase-2 and -3 could not block BV-induced apoptosis in A2058 cells. Data from immunostaining indicated that EndoG and AIF were translocated from mitochondria to the cytosol or nucleus, suggesting that BV induces apoptosis in A2058 cells via a caspase-independent pathway. In addition, cJun N-terminal kinases (JNK) and ERK were rapidly activated after a 5 min incubation with BV, while p38 and AKT were inactivated after 30 min administration of BV. Inhibition of JNK significantly attenuated BV-triggered apoptotic death. Moreover, BV induced a rapid and marked increase in cytosolic calcium ion. Incubation of cells under calcium-free conditions effectively diminished BV-induced apoptosis. Furthermore, when the calcium-free treatment was combined with ouabain, the recovery of cellular calcium fluctuation protected A2058 cells against BV-induced apoptosis. Finally, treatment of A2058 cells with melittin, the major component of BV, resulted in similar elevation of calcium levels and cell killing effects, suggesting that melittin is the major determinant in BV-triggered cell death. These observations provide a molecular explanation for the antiproliferative properties of BV, and suggest that this agent may be useful in treating melanoma.


Assuntos
Apoptose/efeitos dos fármacos , Venenos de Abelha/toxicidade , Abelhas/fisiologia , Cálcio/metabolismo , Caspases/metabolismo , Melanoma/tratamento farmacológico , Animais , Cálcio/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citosol/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/biossíntese , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Formazans/metabolismo , Humanos , MAP Quinase Quinase 4/antagonistas & inibidores , MAP Quinase Quinase 4/biossíntese , Melanoma/metabolismo , Melanoma/patologia , Meliteno/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ouabaína/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sais de Tetrazólio/metabolismo
9.
Life Sci ; 81(23-24): 1602-14, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17977562

RESUMO

Luteolin, a plant flavonoid, has potent anti-inflammatory properties both in vitro and in vivo. However, the molecular mechanism of luteolin-mediated immune modulation has not been fully understood. In this study, we examined the effects of luteolin on the production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)), as well as the expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) in mouse alveolar macrophage MH-S and peripheral macrophage RAW 264.7 cells. Luteolin dose-dependently inhibited the expression and production of these inflammatory genes and mediators in macrophages stimulated with lipopolysaccharide (LPS). Semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) assay further confirmed the suppression of LPS-induced TNF- alpha, IL-6, iNOS and COX-2 gene expression by luteolin at a transcriptional level. Luteolin also reduced the DNA binding activity of nuclear factor-kappa B (NF-kappaB) in LPS-activated macrophages. Moreover, luteolin blocked the degradation of IkappaB-alpha and nuclear translocation of NF-kappaB p65 subunit. In addition, luteolin significantly inhibited the LPS-induced DNA binding activity of activating protein-1 (AP-1). We also found that luteolin attenuated the LPS-mediated protein kinase B (Akt) and IKK phosphorylation, as well as reactive oxygen species (ROS) production. In sum, these data suggest that, by blocking NF-kappaB and AP-1 activation, luteolin acts to suppress the LPS-elicited inflammatory events in mouse alveolar macrophages, and this effect was mediated, at least in part, by inhibiting the generation of reactive oxygen species. Our observations suggest a possible therapeutic application of this agent for treating inflammatory disorders in lung.


Assuntos
Expectorantes/farmacologia , Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Luteolina/farmacologia , Macrófagos Alveolares/metabolismo , NF-kappa B/antagonistas & inibidores , Fator de Transcrição AP-1/antagonistas & inibidores , Animais , Western Blotting , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/biossíntese , Dinoprostona/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Imunofluorescência , Indicadores e Reagentes , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , Macrófagos Alveolares/efeitos dos fármacos , Camundongos , NF-kappa B/genética , Nitritos/metabolismo , Espécies Reativas de Oxigênio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição AP-1/genética
10.
Complement Ther Med ; 30: 79-83, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28137531

RESUMO

BACKGROUND: Previous studies have shown that exercise training in patients with end-stage renal disease could improve their physical functioning and quality of life. Nevertheless, few studies have evaluated the effects of Tai Chi exercise in patients on hemodialysis. OBJECTIVE: To investigate the effects of a Tai Chi exercise intervention on the quality of life and physical functioning in end-stage renal disease patients on hemodialysis. DESIGN: A pre-post experimental design. SETTING: Patients, aged 20 years or older, on hemodialysis recruited from the hemodialysis unit at a medical center in central Taiwan were assigned, based on their own preference, to either a control group (n=25) or an intervention group (n=21). INTERVENTION: A weekly one-hour short-form Yang style Tai Chi session for a total of 12 weeks. MAIN OUTCOME MEASURES: Physical functioning and Kidney Disease Quality of Life (KDQOL) at the baseline and at the end of the intervention. RESULTS: The least square means of repetition of sit-to-stand cycles in one minute (STS-60), 6-min walk test, and gait speed test were significantly improved in the intervention group. In addition, the least square means of the five different dimensions of the KDQOL were all significantly higher in the intervention group, except the SF-12 physical health score. CONCLUSIONS: Improvements in the kidney disease quality of life and physical functioning were observed in Taiwanese patients on hemodialysis with a 12-week Tai Chi exercise intervention.


Assuntos
Exercício Físico/fisiologia , Nefropatias/fisiopatologia , Falência Renal Crônica/fisiopatologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Diálise Renal/métodos , Tai Chi Chuan/métodos
12.
Artigo em Inglês | MEDLINE | ID: mdl-26640495

RESUMO

Mindfulness training has recently gained much research interest because of its putative benefits for both mental and physical health. However, little is available in its effects on Asian students. Therefore, a quasi-experimental pre/posttest design was used to assess the effects of a one-semester mindfulness meditation course in 152 first-year Taiwanese university students and compared with 130 controls. The Chinese version of the College Learning Effectiveness Inventory (CLEI) and a computer software program focused on specific cognitive tasks were used for the evaluation. Results from the analysis of covariance revealed that while the score of the full CLEI scale was significantly higher in the intervention group compared with the control (P = 0.022), none of the comparisons between the nine CLEI subscales were significantly different between the two groups. For the computer cognitive tasks, the intervention group exhibited significantly better performance in the accuracy of the digital vigilance task (P = 0.048), choice reaction time (P = 0.004), spatial working memory (P = 0.042), and digital vigilance task reaction time (P = 0.004). This study showed that a one-semester mindfulness meditation course was able to improve learning effectiveness and both attention and memory aspects of cognitive performance among Taiwanese university students.

13.
Artigo em Inglês | MEDLINE | ID: mdl-23533505

RESUMO

Idiopathic pulmonary fibrosis is a chronic lung disorder characterized by fibroblasts proliferation and extracellular matrix accumulation. Induction of fibroblast apoptosis therefore plays a crucial role in the resolution of this disease. Gallic acid (3,4,5-trihydroxybenzoic acid), a common botanic phenolic compound, has been reported to induce apoptosis in tumor cell lines and renal fibroblasts. The present study was undertaken to examine the role of mitogen-activated protein kinases (MAPKs) in lung fibroblasts apoptosis induced by gallic acid. We found that treatment with gallic acid resulted in activation of c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and protein kinase B (PKB, Akt), but not p38MAPK, in mouse lung fibroblasts. Inhibition of JNK using pharmacologic inhibitor (SP600125) and genetic knockdown (JNK specific siRNA) significantly inhibited p53 accumulation, reduced PUMA and Fas expression, and abolished apoptosis induced by gallic acid. Moreover, treatment with antioxidants (vitamin C, N-acetyl cysteine, and catalase) effectively diminished gallic acid-induced hydrogen peroxide production, JNK and p53 activation, and cell death. These observations imply that gallic acid-mediated hydrogen peroxide formation acts as an initiator of JNK signaling pathways, leading to p53 activation and apoptosis in mouse lung fibroblasts.

14.
PLoS One ; 8(5): e62826, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23675430

RESUMO

Matriptase, a membrane-associated serine protease, plays an essential role in epidermal barrier function through activation of the glycosylphosphatidylinositol (GPI)-anchored serine protease prostasin. The matriptase-prostasin proteolytic cascade is tightly regulated by hepatocyte growth factor activator inhibitor (HAI)-1 such that matriptase autoactivation and prostasin activation occur simultaneously and are followed immediately by the inhibition of both enzymes by HAI-1. However, the mechanisms whereby matriptase acts on extracellular substrates remain elusive. Here we report that some active matriptase can escape HAI-1 inhibition by being rapidly shed from the cell surface. In the pericellular environment, shed active matriptase is able to activate hepatocyte growth factor (HGF), accelerate plasminogen activation, and shed syndecan 1. The amount of active matriptase shed is inversely correlated with the amount of antithrombin (AT) bound to the surface of the keratinocytes. Binding of AT to the surface of keratinocytes is dependent on a functional heparin binding site, Lys-125, and that the N-glycosylation site Asn-135 be unglycosylated. This suggests that ß-AT, and not α-AT, is responsible for regulation of pericellular matriptase activity in keratinocytes. Keratinocytes appear to rely on AT to regulate the level of pericellular active matriptase much more than breast and prostate epithelial cells in which AT regulation of matriptase activity occurs at much lower levels than keratinocytes. These results suggest that keratinocytes employ two distinct serine protease inhibitors to control the activation and processing of two different sets of matriptase substrates leading to different biological events: 1) HAI-1 for prostasin activation/inhibition, and 2) AT for the pericellular proteolysis involved in HGF activation, accelerating plasminogen activation, and shedding of syndecans.


Assuntos
Antitrombinas/farmacologia , Fibrinolisina/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Queratinócitos/efeitos dos fármacos , Serina Endopeptidases/metabolismo , Sindecanas/metabolismo , Antitrombinas/metabolismo , Sítios de Ligação , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Fibrinolisina/genética , Regulação da Expressão Gênica , Heparina/química , Heparina/metabolismo , Fator de Crescimento de Hepatócito/genética , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Masculino , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/efeitos dos fármacos , Glândulas Mamárias Humanas/metabolismo , Especificidade de Órgãos , Próstata/citologia , Próstata/efeitos dos fármacos , Próstata/metabolismo , Ligação Proteica , Proteínas Secretadas Inibidoras de Proteinases/genética , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Serina Endopeptidases/genética , Sindecanas/genética
15.
Life Sci ; 93(24): 924-33, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24140887

RESUMO

AIMS: Luteolin is a natural flavonoid that possesses a variety of pharmacological activities, such as anti-inflammatory and anti-cancer abilities. Whether luteolin regulates the transformation ability of lung cancer cells remains unclear. The current study aims to uncover the effects and underlying mechanisms of luteolin in regulation of and epithelial-mesenchymal transition of lung cancer cells. MAIN METHODS: The lung adenocarcinoma A549 cells were used in this experiment; the cells were pretreated with luteolin followed by administration with TGF-ß1. The expression levels of various cadherin and related upstream regulatory modules were examined. KEY FINDINGS: Pretreatment of luteolin prevented the morphological change and downregulation of E-cadherin of A549 cells induced by TGF-ß1. In addition, the activation of PI3K-Akt-IκBa-NF-κB-Snail pathway which leads to the decline of E-cadherin induced by TGF-ß1 was also attenuated under the pretreatment of luteolin. SIGNIFICANCE: We provide the mechanisms about how luteolin attenuated the epithelial-mesenchymal transition of A549 lung cancer cells induced by TGF-ß1. This finding will strengthen the anti-cancer effects of flavonoid compounds via the regulation of migration/invasion and EMT ability of various cancer cells.


Assuntos
Adenocarcinoma/patologia , Proteínas de Ligação a DNA/fisiologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Expectorantes/farmacologia , Neoplasias Pulmonares/patologia , Luteolina/farmacologia , NF-kappa B/fisiologia , Proteína Oncogênica v-akt/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Fatores de Transcrição/fisiologia , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/farmacologia , Adenocarcinoma de Pulmão , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Transição Epitelial-Mesenquimal/genética , Técnica Indireta de Fluorescência para Anticorpo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indicadores e Reagentes , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição da Família Snail
16.
J Agric Food Chem ; 58(22): 11653-61, 2010 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-20958047

RESUMO

Lonicera japonica (Caprifoliaceae) has been known as an anti-inflammatory herb in traditional Chinese medicine for thousands of years and is used constantly for upper respiratory tract infections. Luteolin, an active flavonoid compound isolated from Lonicera japonica, has a spectrum of biological activities, especially with antioxidative and anti-inflammatory properties. However, whether luteolin has a direct inhibitory effect on lung fibrosis has not been established. In this study, we examined the effects of luteolin on lung fibrosis both in vivo and in vitro. We found that oral administration of luteolin (10 mg/kg) efficiently suppressed the neutrophil infiltration as well as TNF-α and IL-6 elevation in the bronchoalveolar lavage fluid in bleomycin-instilled C57BL/6J mice. Luteolin also alleviated collagen deposition, TGF-ß1 expression, and lung fibrosis upon bleomycin instillation. A similar tendency was observed in both early and delayed luteolin-treated groups. Next, our in vitro studies showed that luteolin inhibited TGF-ß1-induced α-SMA, type I collagen, and vimentin expression in primary cultured mouse lung fibroblasts. Moreover, luteolin significantly blocked TGF-ß1-mediated epithelial marker (E-cadherin) downregulation and mesenchymal cell markers (fibronectin and vimentin) upregulation, as well as retaining epithelial morphology in human alveolar epithelial-derived A549 cells. Additionally, luteolin could attenuate TGF-ß1-induced Smad3 phosphorylation in both lung fibroblasts and A549 cells. These findings suggest that luteolin has a potent antifibrotic activity; this effect was mediated, at least in part, by inhibition of lung inflammation and suppression of myofibroblast differentiation as well as epithelial-to-mesenchymal transition.


Assuntos
Luteolina/administração & dosagem , Extratos Vegetais/administração & dosagem , Fibrose Pulmonar/tratamento farmacológico , Animais , Linhagem Celular , Modelos Animais de Doenças , Humanos , Interleucina-6/imunologia , Lonicera/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/imunologia , Fator de Necrose Tumoral alfa/imunologia
17.
J Agric Food Chem ; 58(5): 2943-51, 2010 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-20151649

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive chronic disorder characterized by the activation of fibroblasts and the overproduction of extracellular matrix. Fibroblast resistance to apoptosis leads to increased fibrosis. Targeting fibroblasts with apoptotic agents represents a major therapeutic intervention for debilitating IPF. Gallic acid (3,4,5-trihydroxybenzoic acid), a naturally occurring plant phenol, has been reported to induce apoptosis in tumor cell lines and renal fibroblasts. However, the effects of gallic acid on lung fibroblasts have not been investigated. The aim of the present study is to determine the effects of gallic acid on primary cultured mouse fibroblasts. Our results showed that gallic acid induces the apoptotic death of fibroblasts via both intrinsic and extrinsic apoptotic pathways by the elevation of PUMA, Fas, and FasL protein levels. Moreover, intracellular reactive oxygen species (ROS) generation and 8-hydroxy-2'-deoxyguanosine production were observed in gallic acid-stimulated fibroblasts. Mechanistic studies showed that gallic acid induces early phosphorylation of p53(Ser18) and histone 2AX(Ser139) (H2AX) via ataxia telangiectasia mutated (ATM) activation in response to ROS-provoked DNA damage. When mouse lung fibroblasts were treated with caffeine, an ATM kinase inhibitor, the levels of p53, phosphorylated p53(Ser18), and cell death induced by gallic acid were significantly attenuated. Additionally, pretreatment with antioxidants drastically inhibited the gallic acid-induced 8-hydroxy-2'-deoxyguanosine (8-OH-dG) formation and phosphorylation of p53(Ser18) and ATM(Ser1981), as well as apoptosis. Our results provide the first evidence of the activation of ROS-dependent ATM/p53 signaling as a critical mechanism of gallic acid-induced cell death in primary cultured mouse lung fibroblasts.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ácido Gálico/farmacologia , Pulmão/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Células Cultivadas , Dano ao DNA , Citometria de Fluxo , Pulmão/citologia , Pulmão/metabolismo , Camundongos
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