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1.
Antioxidants (Basel) ; 11(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35052524

RESUMO

The prominent cultivation of lemongrass (Cymbopogon spp.) relies on the pharmacological incentives of its essential oil. Lemongrass essential oil (LEO) carries a significant amount of numerous bioactive compounds, such as citral (mixture of geranial and neral), isoneral, isogeranial, geraniol, geranyl acetate, citronellal, citronellol, germacrene-D, and elemol, in addition to other bioactive compounds. These components confer various pharmacological actions to LEO, including antifungal, antibacterial, antiviral, anticancer, and antioxidant properties. These LEO attributes are commercially exploited in the pharmaceutical, cosmetics, and food preservations industries. Furthermore, the application of LEO in the treatment of cancer opens a new vista in the field of therapeutics. Although different LEO components have shown promising anticancer activities in vitro, their effects have not yet been assessed in the human system. Hence, further studies on the anticancer mechanisms conferred by LEO components are required. The present review intends to provide a timely discussion on the relevance of LEO in combating cancer and sustaining human healthcare, as well as in food industry applications.

2.
Am J Respir Cell Mol Biol ; 61(2): 257-265, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30811958

RESUMO

Dysfunctional endothelial cell (EC) barrier and increased lung vascular permeability is a cardinal feature of acute lung injury and sepsis that may result in a pathophysiological condition characterized by alveolar flooding, pulmonary edema, and subsequent hypoxemia. In lung ECs, activation of Rho-associated kinase-1 (ROCK1) phosphorylates myosin light chain (MLC)-associated phosphatase at its inhibitory site, which favors phosphorylation of MLC, stress fiber formation, and hyperpermeability during acute lung injury. The role of microRNA-144 (miR-144) has been well investigated in many human diseases, including cardiac ischemia/reperfusion-induced injury, lung cancer, and lung viral infection; however, its role in pulmonary EC barrier regulation remains obscure. Here, we investigated the miR-144-mediated mechanism in the protection of endothelial barrier function in an LPS-induced lung injury model. By using transendothelial electrical resistance and transwell permeability assay to examine in vitro permeability and immunofluorescence microscopy to determine barrier integrity, we showed that ectopic expression of miR-144 effectively blocked lung EC barrier disruption and hyperpermeability in response to proinflammatory agents. Furthermore, using a gain-and-loss-of-function strategy, overexpression of miR-144 significantly decreased ROCK1 expression. Concomitantly, miR-144 inhibits ROCK1-mediated phosphorylation of MLC phosphataseThr853 and thus phosphorylation of MLCThr18/Ser19 to counteract stress fiber formation in LPS-activated EC. Finally, in LPS-challenged mice, intranasal delivery of miR-144 mimic via liposomes attenuated endotoxemia-induced increases in lung wet/dry ratio, vascular permeability, and inflammation. In conclusion, these data suggest that miR-144-attenuated activation of inflammatory ROCK1/MLC pathway in vascular ECs is a promising therapeutic strategy to counter inflammatory lung injury.


Assuntos
Células Endoteliais/metabolismo , Pulmão/metabolismo , MicroRNAs/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Impedância Elétrica , Células Endoteliais/efeitos dos fármacos , Humanos , Inflamação , Lipopolissacarídeos , Lipossomos/metabolismo , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Permeabilidade , Traumatismo por Reperfusão , Transdução de Sinais
3.
Am J Respir Cell Mol Biol ; 60(4): 465-477, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30512967

RESUMO

Recent evidence has shown that microRNAs (miRs) are involved in endothelial dysfunction and vascular injury in lung-related diseases. However, the potential role of miR-34a in the regulation of pulmonary endothelial dysfunction, vascular injury, and endothelial cells (ECs) apoptosis in acute lung injury (ALI)/acute lung respiratory distress syndrome is largely unknown. Here, we show that miR-34a-5p was upregulated in whole lungs, isolated ECs from lungs, and ECs stimulated with various insults (LPS and hyperoxia). Overexpression of miR-34a-5p in ECs exacerbated endothelial dysfunction, inflammation, and vascular injury, whereas the suppression of miR-34a-5p expression in ECs and miR-34a-null mutant mice showed protection against LPS- and hyperoxia-induced ALI. Furthermore, we observed that miR-34a-mediated endothelial dysfunction is associated with decreased miR-34a direct-target protein, sirtuin-1, and increased p53 expression in whole lungs and ECs. Mechanistically, we show that miR-34a leads to translocation of p53 and Bax to the mitochondrial compartment with disruption of mitochondrial membrane potential to release cytochrome C into the cytosol, initiating a cascade of mitochondrial-mediated apoptosis in lungs. Collectively, these data show that downregulating miR-34a expression or modulating its target proteins may improve endothelial dysfunction and attenuate ALI.


Assuntos
Lesão Pulmonar Aguda/patologia , Apoptose/fisiologia , Células Endoteliais/patologia , MicroRNAs/genética , Mitocôndrias/metabolismo , Lesão Pulmonar Aguda/genética , Animais , Citocromos c/metabolismo , Citosol/química , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Pulmão/metabolismo , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sirtuína 1/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
4.
J Adv Res ; 7(3): 473-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27222752

RESUMO

In the present study Terminalia chebula was used as an eco-friendly natural colorant for sustainable textile coloration of woolen yarn with primary emphasis on thermodynamic and kinetic adsorption aspects of dyeing processes. Polyphenols and ellagitannins are the main coloring components of the dye extract. Assessment of the effect of pH on dye adsorption showed an increase in adsorption capacity with decreasing pH. Effect of temperature on dye adsorption showed 80 °C as optimum temperature for wool dyeing with T. chebula dye extract. Two kinetic equations, namely pseudo first-order and pseudo second-order equations, were employed to investigate the adsorption rates. Pseudo second-order model provided the best fit (R (2) = 0.9908) to the experimental data. The equilibrium adsorption data were fitted by Freundlich and Langmuir isotherm models. The adsorption behavior accorded well (R (2) = 0.9937) with Langmuir isotherm model. Variety of eco-friendly and sustainable shades were developed in combination with small amount of metallic mordants and assessed in terms of colorimetric (CIEL(∗) a (∗) b (∗) and K/S) properties measured using spectrophotometer under D65 illuminant (10° standard observer). The fastness properties of dyed woolen yarn against light, washing, dry and wet rubbing were also evaluated.

5.
Sci Rep ; 6: 24135, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-27063893

RESUMO

Chronic inflammation plays a crucial role in the pathogenesis of obesity and insulin resistance. However, the primary mediators that affect energy homeostasis remain ill defined. Here, we report an unexpected role for immediate early response gene X-1 (IEX-1), a downstream target of NF-κB, in energy metabolism. We found that IEX-1 expression was highly induced in white adipose tissue (WAT) in both epidydmal and subcutaneous depots but not in interscapular brown adipose tissue (BAT) in mice fed a high fat diet (HFD). Null mutation of IEX-1 protected mice against HFD-induced adipose and hepatic inflammation, hepatic steatosis, and insulin resistance. Unexpectedly, IEX-1 knockout (IEX-1(-/-)) mice gained markedly less weight on HFD for 20 weeks as compared to wild-type (WT) littermates (37 ± 3 versus 48 ± 2 gm) due to increased energy expenditure. Mechanistically, we showed that IEX-1 deficiency induced browning and activated thermogenic genes program in WAT but not in BAT by promoting alternative activation of adipose macrophages. Consequently, IEX-1(-/-) mice exhibited enhanced thermogenesis (24 ± 0.1 versus 22 ± 0.1 kcal/hour/kg in WT mice) explaining increased energy expenditure and lean phenotype in these mice. In conclusion, the present study suggests that IEX-1 is a novel physiological regulator of energy homeostasis via its action in WAT.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Dieta Hiperlipídica , Proteínas Imediatamente Precoces/genética , Obesidade/etiologia , Animais , Calorimetria , Metabolismo Energético , Fígado Gorduroso/etiologia , Expressão Gênica , Teste de Tolerância a Glucose , Proteínas Imediatamente Precoces/deficiência , Imuno-Histoquímica , Imunofenotipagem , Insulina/sangue , Resistência à Insulina , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , RNA Mensageiro/metabolismo , Termogênese
6.
Int J Occup Environ Health ; 20(3): 189-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25000106

RESUMO

BACKGROUND: Aflatoxins are a metabolite of Aspergillus molds and are widespread in the natural environment. Workers who handle food grains are at increased risk of exposure to aflatoxins and subsequently certain respiratory conditions. In India, more than half of the employed population is engaged in some type of agricultural work, yet little known about the respiratory problems as a result of exposure to aflatoxins among workers who handle food grains in India. OBJECTIVES: The aim of this study was to determine the risk of occupational exposure to aflatoxins in food-grain workers compared to workers who are not occupationally exposed to food grains. METHODS: Bronchoalveolar lavage (BAL) and serum samples from 46 food-grain workers and 44 non-food-grain workers were analyzed for the presence of aflatoxins. Microscopy and culture of BAL samples were performed to detect Aspergillus species. RESULTS: Aflatoxins were detected in 32·6% of the food-grain workers and 9·1% of non food grain workers (P<0·01). A significant difference was also found in BAL culture for Aspergillus (P<0·01) between the two groups. About 47·8% of the food-grain workers and 11·4% of non-food-grain workers had chronic respiratory symptoms. CONCLUSION: Occupational exposure to aflatoxins in food-grain workers was found to be associated with the increased presence of respiratory symptoms.


Assuntos
Aflatoxinas/metabolismo , Agricultura , Aspergillus/isolamento & purificação , Doenças Profissionais/epidemiologia , Exposição Ocupacional , Venenos/metabolismo , Aspergilose Pulmonar/epidemiologia , Adulto , Aflatoxinas/sangue , Idoso , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/microbiologia , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/microbiologia , Venenos/sangue , Prevalência , Aspergilose Pulmonar/microbiologia , Fatores de Risco , Adulto Jovem
7.
J Med Case Rep ; 6: 10, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22236863

RESUMO

INTRODUCTION: Enteropathic arthritis is one of the recognized extraintestinal manifestations of inflammatory bowel disease and affects up to 25% of patients. The treatment options for refractory disease were rather limited and ineffective until the arrival of biologic therapy in the last few years. The use of etanercept was unique for this disease. CASE PRESENTATION: In this case report, a 58-year-old Malay woman with a 17-year history of ulcerative colitis had persistent left knee effusion and synovitis for seven years, despite remission of the primary disease. She had had multiple courses of systemic and intra-articular steroid that caused significant systemic side effects such as impaired fasting glucose, hypertension, cataract, and weight gain. She also had a total left knee replacement for secondary osteoarthritis. But the left knee synovitis and effusion recurred a month after the total knee replacement, and she was subjected to a total synovectomy the following year. In view of failure of remission despite multiple immunosuppressants (100 mg of azathioprine daily, 1 g of sulfasalazine twice a day, 10 mg of prednisolone daily, and 10 mg of methotrexate weekly), 25 mg of subcutaneous etanercept twice weekly was started. After 5 weeks of treatment, complete resolution of left knee effusion and normalization of the inflammatory markers were shown. This continued up to 12 months of follow-up while our patient was on etanercept and 10 mg of methotrexate weekly. No relapse or serious side effects were noted. CONCLUSIONS: This case demonstrates the efficacy of etanercept in recalcitrant enteropathic arthritis with no relapse of the underlying colitis while on treatment. The usage of this tumor necrosis factor inhibitor was unique in this case of rheumatology and gastroenterology.

8.
Hypertension ; 56(4): 705-12, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20713914

RESUMO

Gene-targeted deletion of the immediate early responsive gene X-1 (IEX-1) results in a significant increase in systemic arterial blood pressure, but the underlying mechanism is not understood. Studies of arterial reactivity in isolated aortas revealed normal endothelium-dependent and -independent vasorelaxation and vasoconstriction but reduced cAMP-dependent vasorelaxation in the absence of IEX-1. This defect in cAMP signaling was also evident in endothelium-denuded aortic rings, consistent with the enhancement of mitochondrial O2·- production only in IEX-1-deficient vascular smooth muscle cells, not in endothelial cells. Excessive production of reactive oxygen species at mitochondria augmented the expression of Gα(i2), suppressing cAMP production in vascular smooth muscle cells. The role of mitochondrial reactive oxygen species in the upregulation of Gα(i2) leading to the development of hypertension was supported by the ability of antioxidant or pertussis toxin to restore the cAMP-dependent vasorelaxation to a normal level and reverse established hypertension in IEX-1 homozygous knockout mice. Our results suggest that hypertension in IEX-1 knockout mice may arise primarily from impaired cAMP signaling induced by overproduction of mitochondrial reactive oxygen species in vascular smooth muscle cells and demonstrate a causal relationship between mitochondrial dysfunction and cAMP-dependent vasorelaxation.


Assuntos
AMP Cíclico/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Músculo Liso Vascular/metabolismo , Transdução de Sinais/fisiologia , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/fisiologia , Pressão Sanguínea/fisiologia , Western Blotting , Células Cultivadas , Feminino , Sequestradores de Radicais Livres/farmacologia , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Proteínas Imediatamente Precoces/genética , Técnicas In Vitro , Masculino , Metaloporfirinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Mitocôndrias/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Toxina Pertussis/farmacologia , Rotenona/farmacologia , Superóxidos/antagonistas & inibidores , Superóxidos/metabolismo , Vasodilatação/efeitos dos fármacos
9.
Am J Physiol Renal Physiol ; 299(1): F217-24, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20410217

RESUMO

Systemic infusion of TNF-alpha exerts renal vasoconstriction but caused marked natriuresis in mice. Similar renal responses were also observed during systemic infusion of nitric oxide (NO) synthase inhibitors as opposed to their usual antinatriuretic responses when administered intrarenally. In the present study, we examined the hypothesis that acute NO blockade systemically induces TNF-alpha generation. which induces this natriuretic response. Renal responses to intravenous infusion of the NO synthase inhibitor nitro-L-arginine methyl ester (L-NAME; 0.2 microg x min(-1) x g body wt(-1) for 85 min) and its impact on the plasma level of TNF-alpha were evaluated in anesthetized mice. Plasma TNF-alpha was undetected in untreated mice (n = 7) but was elevated in L-NAME-treated mice (109 +/- 22 pg/ml; P < 0.01 vs. untreated group; n = 7) along with an increase in TNF-alpha protein expression in kidney tissue. L-NAME infusion caused a usual increase in mean arterial pressure (MAP; 98 +/- 3 to 122 +/- 3 mmHg; P < 0.01) and decreases in renal blood flow (RBF; 8.6 +/- 0.3 to 4.4 +/- 0.2 ml x min(-1) x g(-1); P < 0.01) and glomerular filtration rate (GFR; 1.14 +/- 0.07 to 0.77 +/- 0.04 ml x min(-1) x g(-1); P < 0.01) with a marked increase in sodium excretion (U(Na)V; 0.48 +/- 0.10 to 3.52 +/- 0.85 micromol x min(-1) x g(-1); P < 0.01). Interestingly, in mice (n = 7) pretreated with the TNF-alpha blocker etanercept (5 mg/kg sc), the U(Na)V response to l-NAME infusion was markedly blunted (0.58 +/- 0.08 to 1.22 +/- 0.28 micromol x min(-1) x g(-1); P = NS) although responses for MAP, RBF, and GFR were mostly unchanged. However, pretreatment with the superoxide scavenger tempol in mice (n = 7) did not alter the U(Na)V response to L-NAME. These data demonstrate that L-NAME-induced natriuresis is mediated, at least in part, by concomitant generation of TNF-alpha during NO blockade.


Assuntos
Anestesia Geral , Inibidores Enzimáticos/administração & dosagem , Rim/efeitos dos fármacos , NG-Nitroarginina Metil Éster/administração & dosagem , Natriurese/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/sangue , Animais , Pressão Sanguínea/efeitos dos fármacos , Óxidos N-Cíclicos/administração & dosagem , Etanercepte , Sequestradores de Radicais Livres/administração & dosagem , Taxa de Filtração Glomerular/efeitos dos fármacos , Imunoglobulina G/administração & dosagem , Infusões Intravenosas , Injeções Subcutâneas , Rim/irrigação sanguínea , Rim/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase/metabolismo , Receptores do Fator de Necrose Tumoral/administração & dosagem , Circulação Renal/efeitos dos fármacos , Marcadores de Spin , Superóxidos/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Regulação para Cima
10.
Int J Rheum Dis ; 12(2): 136-44, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20374331

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) is a systemic disease of unknown cause. A variety of pulmonary disorders have been described in association with RA. Among the most common are interstitial lung disease (ILD) and bronchiectasis. OBJECTIVES: This study aims to determine the characteristics of RA patients with lung disease in relation to clinical characteristics, pulmonary function test (PFT) and high resolution computed tomography (HRCT) thorax. METHOD: This is a 6-months cross-sectional study involving 63 consecutive RA patients in an outpatient rheumatology clinic. Patients had a mean disease duration of 5 years and above. Disease activity and severity was assessed by Disease Activity Score 28 (DAS28), Health Assessment Questionnaire (HAQ) and Rheumatoid Arthritis Articular Damage (RAAD) score. Full pulmonary function test (PFT) and HRCT of thorax were performed. CONCLUSIONS: The prevalence of RA-ILD is 44% and 67% of patients are asymptomatic. There was significant higher proportion (68%) in patients of Chinese ethnicity who have ILD. Diffusion capacity of carbon monoxide was abnormal in all patients and forced expiratory flow (FEF)(25-75%) was low in 16%. Restrictive pattern was 66.7% by PFT. The most common HRCT findings were reticulation (46%) followed by ground glass opacities (38.1%) and bronchiectasis (28.6%). There was no association between ILD and male gender, duration of the disease, smoking, rheumatoid factor, extra-articular manifestations, disease activity or severity.


Assuntos
Artrite Reumatoide/etnologia , Bronquiectasia/diagnóstico por imagem , Bronquiectasia/etnologia , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etnologia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , Monóxido de Carbono/metabolismo , Estudos Transversais , Avaliação da Deficiência , Feminino , Seguimentos , Fluxo Expiratório Forçado , Humanos , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por Sexo , Inquéritos e Questionários
11.
Am J Physiol Renal Physiol ; 295(6): F1836-44, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18922887

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) has been implicated in the pathogenesis of hypertension and renal injury. However, the direct effects of TNF-alpha on renal hemodynamic and excretory function are not yet clearly defined. We examined the renal responses to infusion of TNF-alpha (0.33 ng.g(-1).min(-1)) in anesthetized mice. Renal blood flow (RBF) and glomerular filtration rate (GFR) were determined by PAH and inulin clearance. The urine was collected from a cannula inserted into the bladder. Following the 60-min control clearance period, TNF-alpha infusion was initiated and 15 min were given for stabilization followed by another 60-min clearance period. TNF-alpha alone (n = 7) caused decreases in RBF (7.9 +/- 0.3 to 6.4 +/- 0.3 ml.min(-1).g(-1)) and GFR (1.04 +/- 0.06 to 0.62 +/- 0.08 ml.min(-1).g(-1)) as well as increases in absolute (0.8 +/- 0.3 to 1.4 +/- 0.3 micromol.min(-1).g(-1)) and fractional excretion of sodium (0.5 +/- 0.2 to 1.5 +/- 0.4%) without affecting arterial pressure. TNF-alpha also increased 8-isoprostane excretion (8.10 +/- 1.09 to 11.13 +/- 1.34 pg.min(-1).g(-1)). Pretreatment with TNF-alpha blocker etanercept (5 mg/kg sc; 24 and 3 h before TNF-alpha infusion; n = 6) abolished these responses. However, TNF-alpha induced an increase in RBF and caused attenuation of the GFR reduction in mice pretreated with superoxide (O(2)(-)) scavenger tempol (2 microg.g(-1).min(-1); n = 6). Pretreatment with nitric oxide (NO) synthase inhibitor nitro-l-arginine methyl ester (0.1 microg.g(-1).min(-1); n = 6) resulted in further enhancement in vasoconstriction while natriuresis remained unaffected in response to TNF-alpha. These data suggest that TNF-alpha induces renal vasoconstriction and hypofiltration via enhancing the activity of O(2)(-) and thus reducing the activity of NO. The natriuretic response to TNF-alpha is related to its direct effects on tubular sodium reabsorption.


Assuntos
Natriurese/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Dinoprosta/análogos & derivados , Dinoprosta/urina , Taxa de Filtração Glomerular/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Infusões Intravenosas , Rim/efeitos dos fármacos , Rim/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Potássio/urina , Circulação Renal/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sódio/urina , Fator de Necrose Tumoral alfa/administração & dosagem , Fator de Necrose Tumoral alfa/genética
12.
Basic Clin Pharmacol Toxicol ; 103(4): 314-21, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18684223

RESUMO

The role of aspirin on vascular endothelial changes during hypercholesterolaemia prior to development of actual atherosclerotic lesions is not known. Therefore, in the present study, we tested the hypothesis that aspirin by its antioxidant action improves endothelial function in a rat model of hypercholesterolaemia. Hypercholesterolaemia was induced in Wistar rats by feeding a 1% cholesterol-rich diet for 10 weeks. Lipid profile, lipid peroxidation and reduced glutathione were estimated in serum. Endothelial function and beta(2)-adrenoceptor activity was tested by studying the dose-response relationship of acetylcholine and isoproterenol, respectively, on isolated aortic tissues in an organ bath setup. Hypercholesterolaemic rats showed a significant increase in total cholesterol, low-density lipoprotein cholesterol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C), and a significant fall in high-density lipoprotein cholesterol (HDL-C) compared to the control rats. Isolated aortic tissues from hypercholesterolaemic rats showed endothelial dysfunction and decreased sensitivity to beta(2)-adrenoceptor. Treatment with aspirin was associated with a fall in total cholesterol, LDL-C and VLDL-C, and a significant rise in serum HDL-C. Aspirin treatment also restored endothelial function and beta(2)-adrenoceptor activity. Hypercholesterolaemic rats showed free radical generation, evident by increase in serum lipid peroxidation and reduction in serum reduced glutathione content compared to the control rats. Aspirin treatment was associated with reduction in free radical stress evident by decreased lipid peroxidation and significantly prevented reduction in glutathione content compared to hypercholesterolaemic controls. Aspirin improves endothelial function and beta(2)-adrenoceptor activity during experimentally induced hypercholesterolaemia in rats, possibly due to an antioxidant effect.


Assuntos
Antioxidantes/uso terapêutico , Aspirina/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Hipercolesterolemia/tratamento farmacológico , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Aorta Torácica/fisiologia , Aspirina/administração & dosagem , Aspirina/farmacologia , Colesterol/sangue , Modelos Animais de Doenças , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Glutationa/sangue , Hipercolesterolemia/sangue , Hipercolesterolemia/metabolismo , Hipercolesterolemia/fisiopatologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/sangue , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/sangue , Receptores Adrenérgicos beta 2/metabolismo , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos
13.
Mol Hum Reprod ; 13(4): 213-22, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17277043

RESUMO

Methylenetetrahydrofolate (MTHFR) and DNMT3b play imperative roles in DNA synthesis and de novo methylation. GSTM1 is involved in detoxification of carcinogens. Mitochondrial DNA deletion has been associated with lower motility in human sperm. We analysed if polymorphisms in MTHFR (C677T and A1298C) and DNMT3b (C46359T) are associated with non-obstructive male infertility. We also analysed if folate, vitamin B(12), homocysteine (Hcy), 8'-hydroxy-2'-deoxygnanosine (8-OHdG) levels, dietary folate intake and mtDNA deletion (4977 bp) affects fertility, such interactions are modified by deletion and methylation of GSTM1. In this case-control study, we included 179 oligoasthenoteratozoospermia patients and 200 fertile men. Single-nucleotide polymorphism analysis was performed by PCR-restriction fragment length polymorphism. The MTHFR (C677T and A1298C) and DNMT3b (C46359T) frequencies did not differ significantly in two groups. GSTM1 in association with mtDNA 4977 deletion is significantly associated with infertility. Plasma folate and vitamin B(12) levels are decreased and total Hcy is elevated in infertile men. GSTM1 methylation status was investigated by methylation-specific PCR. Methylation is significantly correlated with GSTM1 reduced/loss of expression in infertile men. Infertile men have significantly higher 8-OHdG levels. Dietary folate intake is not linked with GSTM1 methylation. Low folate intake in association with CT + TT genotypes (C677T) has significant protective effect on GSTM1 methylation. Results indicate that micronutrients, 8-OHdG levels, mtDNA deletion and GSTM1 promoter methylation are frequent alterations in infertility.


Assuntos
Sequência de Bases , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , DNA Mitocondrial/metabolismo , Glutationa Transferase/genética , Infertilidade Masculina/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Deleção de Sequência , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Estudos de Casos e Controles , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Ácido Fólico/sangue , Frequência do Gene , Predisposição Genética para Doença , Homocisteína/sangue , Humanos , Índia , Infertilidade Masculina/enzimologia , Infertilidade Masculina/metabolismo , Masculino , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Risco , Vitamina B 12/sangue , População Branca/genética , DNA Metiltransferase 3B
14.
Mol Cancer ; 3: 33, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15574200

RESUMO

BACKGROUND: Granulosa cell tumors (GCTs) are relatively rare and are subtypes of the sex-cord stromal neoplasms. Methylation induced silencing in the promoters of genes such as tumor suppressor genes, DNA repair genes and pro-apoptotic genes is recognised as a critical factor in cancer development. METHODS: We examined the role of promoter hypermethylation, an epigenetic alteration that is associated with the silencing tumor suppressor genes in human cancer, by studying 5 gene promoters in 25 GCTs cases by methylation specific PCR and RT-PCR. In addition, the compatible tissues (normal tissues distant from lesion) from three non-astrocytoma patients were also included as the control. RESULTS: Frequencies of methylation in GCTs were 7/25 (28 % for FHIT), 6/25 (24% for FNACF), 3/25 (12% for Cyclin D2), 1/25 (4% for BRCA2) and 14/25 (56%) in RUNX3 genes. Correlation of promoter methylation with clinical characteristics and other genetic changes revealed that overall promoter methylation was higher in more advanced stage of the disease. Promoter methylation was associated with gene silencing in GCT cell lines. Treatment with methylation or histone deacetylation-inhibiting agents resulted in profound reactivation of gene expression. CONCLUSIONS: These results may have implications in better understanding the underlying epigenetic mechanisms in GCT development, provide prognostic indicators, and identify important gene targets for treatment.


Assuntos
Hidrolases Anidrido Ácido/genética , Proteína BRCA2/genética , Ilhas de CpG/genética , Ciclinas/genética , Metilação de DNA , Proteínas de Ligação a DNA/genética , Tumor de Células da Granulosa/genética , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Adulto , Apoptose/genética , Apoptose/fisiologia , Linhagem Celular Tumoral , Subunidade alfa 3 de Fator de Ligação ao Core , Ciclina D2 , Reparo do DNA/genética , Reparo do DNA/fisiologia , Proteína do Grupo de Complementação F da Anemia de Fanconi , Feminino , Inativação Gênica/fisiologia , Genes Supressores de Tumor/fisiologia , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia
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