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1.
BMC Plant Biol ; 20(1): 418, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894043

RESUMO

BACKGROUND: Gender and fertility variation have an impact on mating dynamics in a population because they affect the gene exchange among parental members and the genetic composition of the resultant seed crops. Fertility is the proportional gametic contribution of parents to their progeny. An effective number of parents, derivative of effective population size, is the probability that two alleles randomly chosen from the gamete gene pool originated from the same parent. The effective number of parents is directly related to the fertility variation among parents, which should be monitored for manipulating gene diversity of seed crops. We formulated a fundamental equation of estimating the effective number of parents and applied it to a seed production population. RESULTS: Effective number of parents (Np) was derived from fertility variation (Ψ) considering covariance (correlation coefficient, r) between maternal and paternal fertility. The Ψ was calculated from the coefficient of variation in reproductive outputs and divided into female (ψf) and male (ψm) fertility variation in the population under study. The Np was estimated from the parental Ψ estimated by the fertility variation of maternal (ψf) and paternal (ψm) parents. The gene diversity of seed crops was monitored by Ψ and Np. in a 1.5 generation Pinus koraiensis seed orchard as a case of monoecious species. A large variation of female and male strobili production was observed among the studied 52 parents over four consecutive years, showing statistically significant differences across all studied years. Parental balance curve showed greater distortion in paternal than maternal parents. The Ψ ranged from 1.879 to 4.035 with greater ψm than ψf, and the Np varied from 14.8 to 36.8. When pooled, the relative effective number of parents was improved as 80.0% of the census number. CONCLUSIONS: We recommend the use of fertility variation (i.e., CV, Ψ), Person's product-moment correlation (r), and effective number of parents (Np) as tools for gauging gene diversity of seed crops in production populations. For increasing Np and gene diversity, additional management options such as mixing seed-lots, equal cone harvest and application of supplemental-mass-pollination are recommended.


Assuntos
Produtos Agrícolas/genética , Fertilidade/genética , Flores/genética , Pinus/genética , Pólen/genética , Polinização/genética , Sementes/genética , Melhoramento Vegetal , República da Coreia
2.
Trials ; 20(1): 310, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146774

RESUMO

BACKGROUND: Mild cognitive impairment (MCI) is defined as a decline in cognitive state with preservation of activities of daily living. Medications such as donepezil and rivastigmine have been commonly prescribed for MCI, but their use is controversial. Acupuncture has been widely used in Korea and has been shown to improve cognitive function. The aim of this study is to evaluate the efficacy of acupuncture for MCI and investigate the effect of acupuncture on structural and functional brain changes in patients with MCI. METHODS: This study is a randomized, assessor-blinded, sham-controlled trial. Fifty participants with MCI will be randomly assigned to the acupuncture group (n = 25) or sham acupuncture group (n = 25). The acupuncture group will receive acupuncture treatment at nine acupuncture points (GV20, EX-HN1, bilateral LI4, and ST36) twice a week for 12 weeks. The sham acupuncture group will receive sham acupuncture treatment at the same points with non-penetrating sham needles. Both groups will be restricted from all other treatments for the improvement of cognitive function. The primary outcome measure is the Digit Span Test (DST). The secondary outcome measures are the Digit Symbol Substitution Test (DSST), Korean version of Montreal Cognitive Assessment (MoCA-K), Seoul Neuropsychological Screening Battery-II (SNSB-II), Beck Depression Inventory-II (BDI-II), State-Trait Anxiety Inventory (STAI), working memory (WM) task performance score, and structural/functional brain changes. Outcomes will be assessed at screening, baseline, 4 and 8 weeks, and after the end of treatment. We will also observe adverse events. In the statistical analysis, a full analysis set and per-protocol analysis will be performed. DISCUSSION: This randomized clinical trial aims to examine the efficacy of acupuncture treatment for MCI. Neuropsychological tests, psychological inventories for measuring depression and anxiety, and magnetic resonance imaging will be performed to investigate the underlying neurological mechanisms and the association between cognition, emotion, and brain networks following acupuncture treatment. The results of the trial will provide evidence supporting the efficacy of acupuncture and also add to the neurobiological understanding of acupuncture treatment for MCI. TRIAL REGISTRATION: Clinical Research Information Service, KCT0002896 . Registered on 25 May 2018.


Assuntos
Terapia por Acupuntura/métodos , Disfunção Cognitiva/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia por Acupuntura/efeitos adversos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Cognição , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Humanos , Imageamento por Ressonância Magnética , Avaliação de Resultados em Cuidados de Saúde , Projetos de Pesquisa
3.
BMC Complement Altern Med ; 19(1): 101, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072358

RESUMO

BACKGROUND: Physalin A isolated from Physalis alkekengi var. franchetii has been known to have many pharmacological properties. However, its effect through the Nrf2 pathway has not yet been elucidated. In the present study, we determined the effects of physalin A on cancer chemoprevention via the Nrf2 pathway. METHODS: Experiments were performed in Hepa-1c1c7 and HepG2 cells. The quinone reductase (QR) activity assay was used to assess the activity of physalin A and other compounds isolated from P. alkekengi. The antioxidant response element (ARE) reporter assay was used to determine physalin A induced transcription of Nrf2 target genes, whereas the oligonucleotide pull-down assay was used to investigate Nrf2 binding to the AREs post physalin A treatment. Real-time PCR and western blotting were performed to determine the expression of Nrf2 target genes. Immunocytochemistry was used to determine Nrf2 localization after treatment with physalin A. Kinase inhibitors were used to test the involvement of Nrf2-targeting kinases and the role of ERK and p38 phosphorylation was confirmed using western blotting. RESULTS: Physalin A significantly induced QR activity. As an upstream effector of QR, Nrf2 induced genes containing the ARE, which encode various antioxidants and detoxification enzymes. We observed that physalin A increased the expression of Nrf2 and its target genes in HepG2 cells. Moreover, we observed that physalin A-induced Nrf2 activation was regulated by ERK and p38 kinase in HepG2 cells. CONCLUSIONS: Taken together, we showed that physalin A increased detoxifying enzyme expression via activation of Nrf2 and its target genes. These results imply that physalin A could be a potential chemopreventive agent for liver diseases, as well as cancer.


Assuntos
Antineoplásicos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vitanolídeos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Células Hep G2 , Humanos , NAD(P)H Desidrogenase (Quinona)/metabolismo
5.
J Biochem Mol Toxicol ; 33(5): e22297, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30672058

RESUMO

Igalan is one of the sesquiterpene lactones found in Inula helenium L., which is used as the traditional medicine to treat inflammatory diseases. However, the pharmacological effects of igalan have not been characterized. In this study, we isolated igalan from I. helenium L. and evaluated the effects of igalan on signaling pathways and expression of target genes in HepG2 cells. Igalan activated the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway by increasing the inactive form of GSK3ß, the phosphorylated form of AKT, and the nuclear accumulation of Nrf2. Thus, target genes of Nrf2 such as HO-1 and NQO1 increased in HepG2 cells. Moreover, igalan inhibited the tumor necrosis factor-α (TNF-α)-induced nuclear factor-κB activation and suppressed the expression of its target genes, including TNF-α, interleukin (IL)-6, and IL-8 in HepG2 cells. Our results indicate the potential of igalan as an activator of cellular defense mechanisms and a detoxifying agent.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/biossíntese , Heme Oxigenase-1/biossíntese , Inula/química , Fator 2 Relacionado a NF-E2/metabolismo , Sesquiterpenos/farmacologia , Citocinas/metabolismo , Células Hep G2 , Humanos , Inativação Metabólica/efeitos dos fármacos , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Transdução de Sinais
6.
Sci Rep ; 8(1): 3257, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29459627

RESUMO

Genistein, a phyto-estrogen, can potentially replace endogenous estrogens in postmenopausal women, but the underlying molecular mechanisms remain incompletely understood. To obtain insight into the effect of genistein on bone differentiation, RNA sequencing (RNA-seq) analysis was used to detect differentially expressed genes (DEGs) in genistein-treated vs. untreated MC3T3-E1 mouse osteoblastic cells. Osteoblastic cell differentiation was monitored by measuring osteoblast differentiation factors (ALP production, bone mineralization, and expression of osteoblast differentiation markers). From RNA-seq analysis, a total of 132 DEGs (including 52 up-regulated and 80 down-regulated genes) were identified in genistein-treated cells (FDR q-value < 0.05 and fold change > 1.5). KEGG pathway and Gene Ontology (GO) enrichment analyses were performed to estimate the biological functions of DEGs and demonstrated that these DEGs were highly enriched in functions related to chemotactic cytokines. The functional relevance of DEGs to genistein-induced osteoblastic cell differentiation was further evaluated by siRNA-mediated knockdown in MC3T3-E1 cells. These siRNA knockdown experiments (of the DEGs validated by real-time qPCR) demonstrated that two up-regulated genes (Ereg and Efcab2) enhance osteoblastic cell differentiation, while three down-regulated genes (Hrc, Gli, and Ifitm5) suppress the differentiation. These results imply their major functional roles in bone differentiation regulated by genistein.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Genisteína/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Fitoestrógenos/metabolismo , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Camundongos , Análise de Sequência de RNA
7.
Food Chem Toxicol ; 108(Pt A): 120-127, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28733231

RESUMO

Tussilagonone is a compound derived from the medicinal plant Tussilago farfara L., which is used as a traditional medicine for respiratory diseases, including asthma and pneumonia. Recent reports suggest that tussilagonone exhibits anti-inflammatory effects; however, the scope of protective functions has not been elucidated yet. In this study, we demonstrate that tussilagonone enhances cellular detoxification by increasing quinone reductase activity in Hepa1c1c7 cells. In addition, tussilagonone decreased tert-butyl hydroperoxide(t-BHP)-induced ROS production and cell death, suggesting that it also acts as a potent antioxidant. To verify the molecular mechanism underlying tussilagonone activity, we examined the expression of nuclear factor erythroid 2-related factor 2(Nrf2)-a transcription factor that regulates antioxidant protein expression-in HepG2 cells. Significantly, these results showed that tussilagonone induces Nrf2 activation and nuclear accumulation, resulting in the upregulation of the detoxifying enzymes NAD(P)H quinone dehydrogenase 1(NQO1) and heme oxygenase-1(HO-1) that protect cells from oxidative stress. Further molecular analyses revealed that tussilagonone-induced Nrf2 activation was mediated by ERK1/2 in HepG2 cells. Collectively, these data indicate that tussilagonone attenuates t-BHP-induced ROS and activates quinone reductase activity via Nrf2 pathway activation and target gene expression, and thereby acts as an antioxidant that protects HepG2 cells from oxidative stress and associated damage.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácidos Pentanoicos/farmacologia , Sesquiterpenos/farmacologia , Tussilago/química , Elementos de Resposta Antioxidante , Antioxidantes/metabolismo , Sobrevivência Celular , Células Hep G2 , Humanos , Fator 2 Relacionado a NF-E2/genética , Ácidos Pentanoicos/química , Interferência de RNA , RNA Interferente Pequeno , Espécies Reativas de Oxigênio , Sesquiterpenos/química , Regulação para Cima
8.
Front Hum Neurosci ; 7: 414, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23914165

RESUMO

This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but weak opposite relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion.

9.
J Ethnopharmacol ; 144(2): 225-33, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-22925946

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Historical records reveal that in traditional medicine, a disease similar to diabetes was treated with ginseng. Korean red ginseng has been considered beneficial as a dietary supplement for its anti-diabetic potential. AIM: This study was designed to investigate the prophylactic potential of Korean red ginseng (KRG) extract (Panax ginseng C.A. Meyer Radix Rubra) in a well-established mouse model of Type 1 diabetes (T1D). MATERIALS AND METHODS: The prophylactic effect of KRG extract was evaluated in mice fed with KRG extract for two weeks prior to induction of diabetes by streptozotocin (STZ) administration. Glucose levels and glucose challenge test results of KRG-treated diabetic mice were compared to those of untreated diabetic mice and healthy control mice. Examination of the immune compartments in lymphoid organs and immunohistochemical staining of pancreas for islet cell morphology and insulin producing beta cells were performed. RESULTS: KRG extract significantly lowered blood glucose levels to an average of 250mg/dl from 350mg/dl and improved glucose challenge testing when applied as prophylaxis. Histological findings indicated that KRG extract protected against STZ-induced destruction of pancreatic tissue and restored insulin secretion. Strikingly, this effect was accompanied by restoration of lymphocytes in secondary lymphoid organs, suggesting that KRG extract facilitated immune homeostasis. CONCLUSION: This is the first report to demonstrate the prophylactic function of KRG extract in ameliorating the hyperglycemia of T1D. Immune compartments of diabetic mice were found to be preserved in KRG-treated mice suggesting that Korean red ginseng may benefit T1D patients, not only for its hypoglycemic but also for its immunomodulatory effects.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Panax , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Glicemia/análise , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Feminino , Hipoglicemiantes/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Baço/citologia
10.
Food Chem Toxicol ; 49(9): 2370-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21723364

RESUMO

The potential health benefits of tea have long been studied. This study examined the role of powdered sea buckthorn leaf tea (SLT) in high-fat diet-induced obese mice. The mice were fed two different doses of SLT (1% and 5%, wt/wt) for six weeks. SLT suppressed body weight gain in a dose-dependent manner and significantly reduced visceral fat, plasma levels of leptin, triglyceride and total cholesterol and ALT activity compared with the high-fat-fed control mice. SLT also decreased hepatic triglyceride and cholesterol concentrations and lipid accumulation, whereas elevated fecal lipid excretion. High-fat feeding resulted in simultaneously decreasing hepatic FAS and G6PD activities and increasing PAP, ß-oxidation and CPT activities. However, SLT supplementation during high-fat feeding led to a significant decrease in PAP, ß-oxidation and CPT activities with a simultaneous increase in G6PD activity. The hepatic CYP2E1 activity and hepatic and erythrocyte lipid peroxides were significantly lowered with SLT supplements. Hepatic and erythrocyte SOD and CAT activities were also increased with SLT supplements in a dose-dependent manner, whereas GSH-Px activity was increased in erythrocytes only. These results indicate that SLT has potential anti-visceral obesity and antioxidant effects mediated by the regulation of lipid and antioxidant metabolism in high-fat diet-induced obese mice.


Assuntos
Antioxidantes/uso terapêutico , Gorduras na Dieta/administração & dosagem , Hippophae/química , Obesidade Abdominal/tratamento farmacológico , Chá , Animais , Peso Corporal , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Pós , Aumento de Peso
11.
ACS Nano ; 5(5): 3839-48, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21517103

RESUMO

A wide variety of drug delivery systems have been developed for the delivery of anticancer agents. One of the most frequently used natural biomaterials in drug delivery systems is polysaccharides; however, they are difficult to digest and to eliminate from the body after systemic administration due to their high molecular weight natures and the absence of degrading enzymes. Therefore, the development of degradable and eliminable natural biomaterials is critical for successful in vivo applications. In the present study, we report the development of self-assembled biodegradable nanoparticles based on recombinant human gelatin (rHG) modified with alpha-tocopheryl succinate (TOS). The rHG-TOS nanoparticles efficiently encapsulated 17-AAG (17-allylamino-17-demethoxygeldanamycin), a small molecular anticancer drug targeting heat shock protein 90. The formation of 17-AAG-loaded nanoparticles was confirmed using TEM and dynamic light scattering analysis and found to be within the size of 90-220 nm. The loading efficiency, sustained release pattern, and stability of 17-AAG from the rHG-TOS nanoparticles were determined using HPLC. Furthermore, the passive targeting of rHG-TOS nanoparticles to the tumor area via enhanced permeability and retention effect was examined by noninvasive live animal imaging in a tumor mouse model. Finally, the 17-AAG-loaded nanoparticles were nonimmunogenic and more efficient than free 17-AAG in manifesting an anticancer effect in the tumor model. Overall, our data demonstrate rHG-TOS as a promising tool for the delivery of 17-AAG featuring therapeutic efficacy and biocompatibility.


Assuntos
Gelatina/química , Glucosídeos/uso terapêutico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Nanocápsulas/química , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Terpenos/uso terapêutico , alfa-Tocoferol/química , Animais , Gelatina/genética , Glucosídeos/química , Humanos , Camundongos , Neoplasias Experimentais/patologia , Proteínas Recombinantes/química , Terpenos/química
12.
J Agric Food Chem ; 59(1): 222-8, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21126077

RESUMO

The present study examined the effects of tangeretin, a polymethoxylated flavonone present in citrus fruits, on ultraviolet B (UVB)-induced cyclooxygenase-2 (COX-2) expression in JB6 P+ mouse skin epidermal cells. Tangeretin suppressed UVB-induced COX-2 expression and transactivation of nuclear factor-κB and activator protein-1 in JB6 P+ cells. Moreover, tangeretin blocked UVB-induced phosphorylation of Akt and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated protein kinase, c-Jun N-terminal kinase, and p38, and attenuated the phosphorylation of MAPK kinases 1/2, 3/6, and 4. Tangeretin also limited the endogenous generation of reactive oxygen species (ROS), thereby protecting the cells against oxidative stress. However, tangeretin did not scavenge the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and influence the nicotinamide adenine dinucleotide phosphate oxidase activity. These results suggest that the anti-inflammatory effects of tangeretin stem from its modulation of cell signaling and suppression of intracellular ROS generation. Tangeretin may have a potent chemopreventive effect in skin cancer.


Assuntos
Ciclo-Oxigenase 2/genética , Regulação para Baixo , Epiderme/enzimologia , Flavonas/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Citrus sinensis/química , Ciclo-Oxigenase 2/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/efeitos da radiação , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/efeitos da radiação , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Transdução de Sinais/efeitos dos fármacos , Raios Ultravioleta
13.
Cancer Prev Res (Phila) ; 3(4): 454-65, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20233901

RESUMO

Nontoxic small molecules with multitargeting effects are believed to have potential in cancer prevention. Dietary phytochemicals were shown to exhibit cancer-preventive effects attributed to their antioxidant capacities. In this report, we show that the natural compound 5-deoxykaempferol (5-DK) exerts a chemopreventive effect on UVB-induced skin carcinogenesis by targeting multiple signaling molecules. 5-DK suppressed the UVB-induced expression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor in mouse skin epidermal JB6 P+ cells. Moreover, 5-DK inhibited phosphorylation of MKK3/6, MKK4, and Akt, but had no effect on phosphorylation of Src, extracellular signal-regulated kinases, or ribosomal S6 kinase (RSK). However, 5-DK affected multiple targets by reducing Src, phosphoinositide 3-kinase (PI3K), and RSK2 activities. In particular, pull-down assays revealed that 5-DK specifically bound to and competed with ATP for binding with Src, PI3K, and RSK2. Exposure to 5-DK significantly suppressed UVB-induced tumorigenesis in mouse skin in a dose-dependent manner, and it inhibited the UVB-induced expression of COX-2, proliferating cell nuclear antigen, vascular endothelial growth factor, and matrix metalloproteinase-9. Our data suggest that 5-DK docks at the ATP-binding site of Src, PI3K, and RSK2. For RSK2, the ATP-binding site is located between the N- and C-lobes of the kinase domain. Taken together, our results indicate that 5-DK holds promise for the treatment of UVB-induced skin cancer by targeting Src, PI3K, and RSK2 signaling.


Assuntos
Antineoplásicos/farmacologia , Quempferóis/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Animais , Western Blotting , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/efeitos dos fármacos , Fabaceae , Flavonoides/farmacologia , Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Camundongos , Camundongos Pelados , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Neoplasias Cutâneas/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Quinases da Família src/efeitos dos fármacos , Quinases da Família src/metabolismo
14.
J Nutr Biochem ; 21(8): 680-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19576746

RESUMO

Cocoa, a good source of dietary antioxidative polyphenols, exhibited anticarcinogenic activity in animal models, but the molecular mechanisms of the chemopreventive potential of cocoa remain unclear. Inhibition of gap-junction intercellular communication (GJIC) is strongly related to tumorigenesis. Cocoa polyphenol extracts (CPE) dose dependently attenuated hydrogen peroxide (H(2)O(2))-induced inhibition of GJIC in rat liver epithelial (RLE) cells. CPE inhibited the H(2)O(2)-induced phosphorylation and internalization of connexin 43, which is a regulating protein of GJIC in RLE cells. The H(2)O(2)-induced accumulation of reactive oxygen species and activation of extracellular signal-regulated kinase were inhibited by CPE treatment. However, CPE did not block H(2)O(2)-induced phosphorylation of p38 mitogen-activated protein kinase. An ex vivo kinase assay demonstrated that CPE inhibited the H(2)O(2)-induced mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK) 1 activity in RLE cell lysates. Ex vivo pull-down assay data revealed that CPE directly bound with MEK1 to inhibit MEK1 activity. These results indicate that CPE protects against the H(2)O(2)-induced inhibition of GJIC through antioxidant activity and direct inhibition of MEK activity, which may contribute to its chemopreventive potential.


Assuntos
Cacau/química , Comunicação Celular/efeitos dos fármacos , Conexina 43/metabolismo , Flavonoides/farmacologia , Junções Comunicantes/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fenóis/farmacologia , Animais , Linhagem Celular , Fosforilação , Extratos Vegetais/farmacologia , Polifenóis , Ratos
15.
J Agric Food Chem ; 56(21): 10422-7, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18828601

RESUMO

(-)-Epigallocatechin gallate (EGCG), a polyphenolic compound found in green tea, is a promising chemopreventive agent against cancer due to its strong antiproliferative effects on cancer cells; however, its possible toxicity and carcinogenicity must be investigated before EGCG can be used as a dietary supplement for chemoprevention. The inhibition of gap junctional intercellular communication (GJIC) is strongly associated with carcinogenesis, particularly the tumor promotion process; thus, we investigated the effects of EGCG on GJIC in WB-F344 normal rat liver epithelial (RLE) cells. EGCG, but not (-)-epicatechin (EC), another polyphenol found in green tea, inhibited GJIC in a dose-dependent and reversible manner in RLE cells. EGCG also induced the phosphorylation of connexin 43 (Cx43), a major regulator of GJIC. The phosphorylation of extracellular signal-regulated protein kinase 1/2 (ERK1/2) was also observed in EGCG-treated RLE cells. The inhibition of GJIC and phosphorylation of Cx43 and ERK1/2 by EGCG were completely blocked by U0126, a pharmacological inhibitor of mitogen-activated protein kinase/ERK kinase. EGCG generated a larger amount of hydrogen peroxide than EC in a dose-dependent manner. Furthermore, catalase partially inhibited the EGCG-induced inhibition of GJIC and the phosphorylation of Cx43 and ERK1/2. These results indicated that EGCG inhibited GJIC mainly due to its prooxidant activity.


Assuntos
Catequina/análogos & derivados , Comunicação Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Flavonoides/farmacologia , Junções Comunicantes/efeitos dos fármacos , Fenóis/farmacologia , Chá/química , Animais , Catequina/farmacologia , Células Cultivadas , Conexina 43/metabolismo , Células Epiteliais/fisiologia , Junções Comunicantes/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Polifenóis , Ratos
16.
Am J Physiol Regul Integr Comp Physiol ; 290(5): R1468-78, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16384859

RESUMO

The kidney plays an important role in ion regulation in both freshwater and seawater fish. However, ion transport mechanisms in the teleost kidney are poorly understood, especially at the molecular level. We have cloned a kidney-specific SLC26 sulfate/anion exchanger from rainbow trout (Oncorhynchus mykiss) that is homologous to the mammalian SLC26A1 (Sat-1). Excretion of excess plasma sulfate concentration after Na2SO4 injection corresponded to significantly higher expression of the cloned SLC26A1 mRNA. Detailed morphological observation of rainbow trout renal tubules was also performed by light microscopy and transmission electron microscopy. According to the structure of brush border and tubular system in the cytoplasm, renal tubules of rainbow trout were classified into proximal tubule first and second (PI and PII) segments and distal tubules. In situ hybridization revealed that SLC26A1 anion exchanger mRNA is specifically localized in the PI segment of kidneys from both seawater- and freshwater-adapted rainbow trout. With immunocytochemistry, Na+-K+-ATPase and vacuolar-type H+-ATPase were colocalized to the same cells and distributed in the basolateral and the apical membranes, respectively, of the cells where the SLC26A1 mRNA expressed. These findings suggest that the cloned kidney-specific SLC26A1 is located in kidney proximal tubules and is involved in excretion of excess plasma sulfate in rainbow trout.


Assuntos
Rim/fisiologia , Oncorhynchus mykiss/metabolismo , Sulfatos/metabolismo , Animais , Transporte Biológico Ativo , Northern Blotting , Western Blotting , Clonagem Molecular , Primers do DNA , DNA Complementar/biossíntese , DNA Complementar/genética , Imuno-Histoquímica , Hibridização In Situ , Rim/metabolismo , Rim/ultraestrutura , Microscopia Eletrônica de Transmissão , ATPase Trocadora de Sódio-Potássio/metabolismo , Distribuição Tecidual , ATPases Vacuolares Próton-Translocadoras/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-15055931

RESUMO

Biofilms occurring in seepage groundwater contaminated with petroleum in an urban subway drainage system were characterized. The development of biofilms was observed only in the sites where petroleum-contaminated groundwater had seeped or was seeping. Moreover, the conditions of the biofilms such as color and development extent were influenced by the amount of spilled petroleum: By increasing the amount of spilled petroleum, the amount of biofilms increased and its color whitened. It deteriorated and became dark-brown if the contaminated groundwater did not seep any more. These facts indicate that the biofilms can be used as a preliminary indicator to identify the locations of fuel contaminated sumps and seeps without a more detailed assessment such as instrumental analysis. The biofilms were capable of degrading petroleum at 15 degrees C, which is similar to the average temperature of the seepage groundwater. Filamentous bacteria, Sphaerotilus spp., were isolated from the biofilms. It is considered that these bacteria are responsible for the development of biofilms in the seepage groundwater contaminated with petroleum because they can secrete extracellular polymeric substances.


Assuntos
Biofilmes , Petróleo , Sphaerotilus/classificação , Poluentes Químicos da Água , Biodegradação Ambiental , Humanos , Sphaerotilus/isolamento & purificação , Sphaerotilus/metabolismo
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