Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Rev Med Chil ; 141(1): 23-7, 2013 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-23732410

RESUMO

BACKGROUND: Smoking may hamper female fertility, probably modifying ovarian reserve. Antimüllerian hormone (AMH) is an accurate marker for ovarian reserve. AIM: To look for an association between smoking status and plasma AMH concentration. PATIENTS AND METHODS: A cohort of 141 infertile women in a university setting in Santiago, Chile was studied. Demographic and smoking data, including the number of cigarettes smoked during the last week, were collected. A blood sample was obtained and kept frozen until determination of AMH by ELISA and follicle stimulating hormone (FSH) and estradiol at day three of the menstrual cycle, by radioimmunoanalysis. RESULTS: Thirty two participants smoked (23%). There were no significant differences in age, parity, body mass index, causes of infertility and day three FSH and estradiol between smokers and nonsmokers. According to a regression analysis, there was a significant decrease in AMH concentration with age and active cigarette smoking. A drop in AMH of -0.189 ng/mL with a unitary change in age and a decrease of -2.29 ng/mL when everything else remains constant, except the smoking status, were established (p < 0.001 and r2 = 0.134). However, no dose response was observed when the number of cigarettes smoked during the last week were introduced in the model. Furthermore, no significant association of plasma AMH with day three plasma FSH and estradiol concentrations was observed. CONCLUSIONS: Cigarette smoking is associated with decreased AMH plasma concentrations among infertile women. However there was no dose response relationship. The mechanisms underlying this association are unknown and further investigation is required.


Assuntos
Hormônio Antimülleriano/sangue , Infertilidade Feminina/sangue , Ovário/metabolismo , Fumar/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Modelos Lineares , Fumar/efeitos adversos , Estatísticas não Paramétricas
2.
Biochim Biophys Acta ; 1830(6): 3796-806, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23541989

RESUMO

BACKGROUND: Obesity is a serious health problem all over the world, and inhibition of adipogenesis constitutes one of the therapeutic strategies for its treatment. Carnosic acid (CA), the main bioactive compound of Rosmarinus officinalis extract, inhibits 3T3-L1 preadipocytes differentiation. However, very little is known about the molecular mechanism responsible for its antiadipogenic effect. METHODS: We evaluated the effect of CA on the differentiation of 3T3-L1 preadipocytes analyzing the process of mitotic clonal expansion, the level of adipogenic markers, and the subcellular distribution of C/EBPß. RESULTS: CA treatment only during the first day of 3T3-L1 differentiation process was enough to inhibit adipogenesis. This inhibition was accompanied by a blockade of mitotic clonal expansion. CA did not interfere with C/EBPß and C/EBPδ mRNA levels but blocked PPARγ, and FABP4 expression. C/EBPß has different forms known as LIP and LAP. CA induced an increase in the level of LIP within 24h of differentiation, leading to an increment in LIP/LAP ratio. Importantly, overexpression of LAP restored the capacity of 3T3-L1 preadipocytes to differentiate in the presence of CA. Finally, CA promoted subnuclear de-localization of C/EBPß. CONCLUSIONS: CA exerts its anti-adipogenic effect in a multifactorial manner by interfering mitotic clonal expansion, altering the ratio of the different C/EBPß forms, inducing the loss of C/EBPß proper subnuclear distribution, and blocking the expression of C/EBPα and PPARγ. GENERAL SIGNIFICANCE: Understanding the molecular mechanism by which CA blocks adipogenesis is relevant because CA could be new a food additive beneficial for the prevention and/or treatment of obesity.


Assuntos
Abietanos/farmacologia , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Antioxidantes/farmacologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Diferenciação Celular/efeitos dos fármacos , PPAR gama/metabolismo , Extratos Vegetais/farmacologia , Rosmarinus/química , Transdução de Sinais/efeitos dos fármacos , Células 3T3-L1 , Abietanos/química , Adipócitos/citologia , Animais , Antioxidantes/química , Diferenciação Celular/fisiologia , Proteínas de Ligação a Ácido Graxo/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Camundongos , PPAR gama/genética , Extratos Vegetais/química , Transdução de Sinais/fisiologia
3.
Rev. méd. Chile ; 141(1): 23-27, ene. 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-674041

RESUMO

Background: Smoking may hamperfemale fertility, probably modifying ovarian reserve. Antimüllerian hormone (AMH) is an accurate marker for ovarian reserve. Aim: To look for an association between smoking status and plasma AMH concentration. Patients and Methods: A cohort of 141 infertile women in a university setting in Santiago, Chile was studied. Demographic and smoking data, including the number of cigarettes smoked during the last week, were collected. A blood sample was obtained and kept frozen until determination of AMH by ELISA and follicle stimulating hormone (FSH) and estradiol at day three of the menstrual cycle, by radioimmunoanalysis. Results: Thirty two participants smoked (23%). There were no significant differences in age, parity, body mass index, causes of infertility and day three FSH and estradiol between smokers and nonsmokers. According to a regression analysis, there was a significant decrease in AMH concentration with age and active cigarette smoking. A drop in AMH of -0.189 ng/mL with a unitary change in age and a decrease of -2.29 ng/mL when everything else remains constant, except the smoking status, were established (p < 0.001 and r2 = 0.134). However, no dose response was observed when the number of cigarettes smoked during the last week were introduced in the model. Furthermore, no significant association ofplasma AMH with day three plasma FSH and estradiol concentrations was observed. Conclusions: Cigarette smoking is associated with decreased AMHplasma concentrations among infertile women. However there was no dose response relationship. The mechanisms underlying this association are unknown and further investigation is required.


Assuntos
Adulto , Feminino , Humanos , Hormônio Antimülleriano/sangue , Infertilidade Feminina/sangue , Ovário/metabolismo , Fumar/sangue , Biomarcadores/sangue , Modelos Lineares , Fumar/efeitos adversos , Estatísticas não Paramétricas
4.
World J Microbiol Biotechnol ; 29(1): 137-44, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22961443

RESUMO

Bacterial resistance to antibiotics has become a serious problem of public health. Along with the controlled permeability by the cell-wall, active efflux systems can provide resistance by extruding antibiotics. Carnosic acid is capable to potentiate the antimicrobial activity of several antibiotics. However, the underlying molecular mechanism governing this effect remains unclear. The present study aims to investigate the effect of carnosic acid on the transport of ethidium bromide, on the permeability or the membrane potential in Enterococcus faecalis and Staphylococcus aureus. By using fluorimetric assays it was demonstrated that in E. faecalis, carnosic acid is a modulator of the uptake and efflux of ethidium bromide which does not induce cell membrane permeabilization phenomena. Such effect was sensitive to the inhibition caused by both the proton-motive force carbonyl cyanide m-chlorophenylhydrazone and the calcium antagonist verapamil, but not to vanadate, an ATPase inhibitor. In this work it was demonstrated, for the first time, that the activity of carnosic acid on the uptake/efflux of ethidium bromide is correlated with its capacity to change the membrane potential gradient in S. aureus and E. faecalis. In conclusion, carnosic acid is a natural compound, structurally unrelated to known antibiotics, which can function as an efflux pump modulator by dissipation of the membrane potential. Therefore, carnosic acid would be a good candidate to be employed as a novel therapeutic agent to be used in combination therapies against drug-resistant enterococci and S. aureus infections.


Assuntos
Abietanos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Transporte Biológico/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Farmacorresistência Bacteriana Múltipla , Enterococcus faecalis/metabolismo , Etídio/metabolismo , Etídio/farmacocinética , Potenciais da Membrana/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Força Próton-Motriz/efeitos dos fármacos , Staphylococcus aureus/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...