No description available.

Phthalate esters (phthalates) such as dibutylphthalate (DBP) are commonly used as plasticisers and pesticides in a variety of products such as children‟s plastic toys, food packaging, cosmetics, medical equipment (including surgical equipment), and acaricides. Because of their widespread use phthalates are ubiquitous environmental contaminants that humans are commonly exposed to. Phthalates are known endocrine-disrupting chemicals (EDCs) that are well known to cause male reproductive defects such as cryptorchidism (failed descent of the testes) and hypospadias (malformations in the urethra) in a range of different species if they are exposed in utero. They do this by reducing testosterone production in Leydig cells, which are the primary site of testosterone biosynthesis in the male. Because phthalates are dose-additive they are considered to share the same mechanism of toxicity. However, the details of phthalates mechanism of toxicity are not fully understood. The aim of this research was to investigate the effects of DBP on the steroidogenesis pathway using the cultured rat Leydig cell cancer line R2C as a Leydig cell model. R2C cells were exposed to a range of DBP concentrations (10 μg/mL, 5 μg/mL, 1 μg/mL, and 0.1 μg/mL) and their steroid hormone production was analysed using reverse phase HPLC. R2C cells did not synthesise testosterone at detectable levels. However, DBP exposure stimulated cortisol biosynthesis at all concentrations but caused no change in progesterone biosynthesis. This cortisol stimulation in Leydig cells has not been observed before. Because cortisol and testosterone compete for precursors an increase in cortisol synthesis could starve testosterone synthesis of precursors. On top of this it has been shown that glucocorticoids including cortisol have an adverse effect on Leydig cell development reducing steroid production and even causing apoptosis. This could explain how DBP and other phthalates can cause male developmental defects such as cryptorchidism and hypospadias.

No description available.

Objetivo:Existemevidências crescentes na literatura da participação do estresseoxidativonaprogressão e agressividade da endometriose. Nesse estudoprospectivo e controlado, foram medidos seis marcadores de estresse oxidativo com a finalidade de relacioná-los com a severidade e progressão da endometriose além debuscarum marcador diagnóstico para a doença. Pacientes e Métodos:Entre Julho de 2010 e Agosto de 2011, 62 pacientes consecutivas com diagnóstico histológico de endometriose foram identificadas como elegíveis para esse estudo. Após os critérios de exclusão, 44 pacientes foram alocadas em três grupos: Grupo A (estádios I/II da ASRM/1996), (n=14), grupo B (estádios III/IV da ASRM/1996),(n=16) e grupo controle (n=14). Os seguintes marcadores foram avaliados no fluido peritoneal e no tecido com endometriose: 8-hidroxi-2- deoxiguanosina (8-OHdG), 8-oxo-guaninaglicosilase (OGG1),proteínacarbonil (PC), oxidação lipídica (LPO), espécies reativas de oxigênio (ROS); capacidade totalantioxidante (TAC). Resultados: Observou-se elevação estatisticamente significante do 8 OhdG e da PC. Notou-se diminuição significativa na expressão do reparo de DNA (OGG1) em estádios avançados de endometriose. (p<0.001, p=0.001, p=0.033 respectivamente). Não notamos significância estatística entre os três grupos estudados nos marcadores ROS,CAT e LPO. Utilizando-se um modelo estatístico multivariável e as curvas ReceiverOperatingCharacteristics(ROC) construiu-se um modelo preditivo de severidade de doença. A habilidade do modelo de distinguir 16 entre os grupos A, B e o grupo controlefoi alta. O modelo foi capaz de diferenciar aproximadamente 9 em cada 10 pacientes incluídas (acerto/corrido foi de 87%). Conclusão:O aumento da lesão no DNA e a diminuição da atividade enzimática de reparo de DNA podem estar relacionados com a progressão da endometriose. Nossos resultados indicam que marcadores oxidativos de agressão celular podem se tornar testes valiosospara se verificar a severidade da endometriose / Objective: There is increasing evidence that oxidative stress is one of the key factors for endometriosis progression. In this prospective controlled trial, we measured six different biomarkers of oxidative stress targeting protein, lipid and DNA to quantify the severity and progression of endometriosis and establish a diagnostic marker for the disease. Methods: 62 consecutive patients were identified to be enrolled in this study. After exclusion criteria, 44 patients were allocated in three groups: Group A (Stage I/II - ASRM/1996), (n=14), Group B(Stage III/IV ASRM/1996), (n=16), and control group (n=14). Levels of 8 hydroxy- deoxyguanosine (8 OHdG), 8- oxoguanine DNA glycosylase (OGG1), protein carbonyl (PC), lipid peroxidation (LPO), reactive oxygen species (ROS); total antioxidant capacity (TAC) were accessed in peritoneal fluid and tissue. Results: 8-OhdG and PC levels were found to be significantly higher in patients with endometriosis, in addition OGG1 expression was found to be significantly lower in patients with endometriosis (p<0.001, p=0.001, p=0.033 respectively); however, stages I/II, stages III/IV, and control group showed comparable levels of ROS, TAC and LPO. A predictive model was built using multivariable analyses and receiver operating characteristics curves. The ability to predict and distinguish between groups A, B and control patients washigh. The model was corrected in proximally 9 out of 10 patients included (Model/Corrected ratio was 87%). Conclusion: Higher level of DNA damage and 19 lower expression of DNA repair activity may be related with endometriosis progression. Our results indicate that oxidative stress as a biomarker of cell injury might be a useful and reliable quantitative test of endometriosis severity

Objetivo:Existemevidências crescentes na literatura da participação do estresseoxidativonaprogressão e agressividade da endometriose. Nesse estudoprospectivo e controlado, foram medidos seis marcadores de estresse oxidativo com a finalidade de relacioná-los com a severidade e progressão da endometriose além debuscarum marcador diagnóstico para a doença. Pacientes e Métodos:Entre Julho de 2010 e Agosto de 2011, 62 pacientes consecutivas com diagnóstico histológico de endometriose foram identificadas como elegíveis para esse estudo. Após os critérios de exclusão, 44 pacientes foram alocadas em três grupos: Grupo A (estádios I/II da ASRM/1996), (n=14), grupo B (estádios III/IV da ASRM/1996),(n=16) e grupo controle (n=14). Os seguintes marcadores foram avaliados no fluido peritoneal e no tecido com endometriose: 8-hidroxi-2- deoxiguanosina (8-OHdG), 8-oxo-guaninaglicosilase (OGG1),proteínacarbonil (PC), oxidação lipídica (LPO), espécies reativas de oxigênio (ROS); capacidade totalantioxidante (TAC). Resultados: Observou-se elevação estatisticamente significante do 8 OhdG e da PC. Notou-se diminuição significativa na expressão do reparo de DNA (OGG1) em estádios avançados de endometriose. (p<0.001, p=0.001, p=0.033 respectivamente). Não notamos significância estatística entre os três grupos estudados nos marcadores ROS,CAT e LPO. Utilizando-se um modelo estatístico multivariável e as curvas ReceiverOperatingCharacteristics(ROC) construiu-se um modelo preditivo de severidade de doença. A habilidade do modelo de distinguir 16 entre os grupos A, B e o grupo controlefoi alta. O modelo foi capaz de diferenciar aproximadamente 9 em cada 10 pacientes incluídas (acerto/corrido foi de 87%). Conclusão:O aumento da lesão no DNA e a diminuição da atividade enzimática de reparo de DNA podem estar relacionados com a progressão da endometriose. Nossos resultados indicam que marcadores oxidativos de agressão celular podem se tornar testes valiosospara se verificar a severidade da endometriose / Objective: There is increasing evidence that oxidative stress is one of the key factors for endometriosis progression. In this prospective controlled trial, we measured six different biomarkers of oxidative stress targeting protein, lipid and DNA to quantify the severity and progression of endometriosis and establish a diagnostic marker for the disease. Methods: 62 consecutive patients were identified to be enrolled in this study. After exclusion criteria, 44 patients were allocated in three groups: Group A (Stage I/II - ASRM/1996), (n=14), Group B(Stage III/IV ASRM/1996), (n=16), and control group (n=14). Levels of 8 hydroxy- deoxyguanosine (8 OHdG), 8- oxoguanine DNA glycosylase (OGG1), protein carbonyl (PC), lipid peroxidation (LPO), reactive oxygen species (ROS); total antioxidant capacity (TAC) were accessed in peritoneal fluid and tissue. Results: 8-OhdG and PC levels were found to be significantly higher in patients with endometriosis, in addition OGG1 expression was found to be significantly lower in patients with endometriosis (p<0.001, p=0.001, p=0.033 respectively); however, stages I/II, stages III/IV, and control group showed comparable levels of ROS, TAC and LPO. A predictive model was built using multivariable analyses and receiver operating characteristics curves. The ability to predict and distinguish between groups A, B and control patients washigh. The model was corrected in proximally 9 out of 10 patients included (Model/Corrected ratio was 87%). Conclusion: Higher level of DNA damage and 19 lower expression of DNA repair activity may be related with endometriosis progression. Our results indicate that oxidative stress as a biomarker of cell injury might be a useful and reliable quantitative test of endometriosis severity