Correlation between urinary concentration of malondialdehyde and DNA damage in people exposed to mercury

ABSTRACT: To determine whether the extent of DNA damage correlates with the concentration of malondialdehyde (MDA) in urine of individuals occupationally exposed to mercury. Methods: We evaluated 64 medical records (32 from exposed persons and 32 from unexposed controls). In both groups we analyzed the comet assay data (percentage of DNA in the tail), as well as the levels of MDA and mercury in the urine. We compared the MDA concentrations, and the changes in the comet assay between the groups and the correlation between these variables. Results: MDA concentrations were higher in exposed persons than in controls (median 1.28 vs. 0.51 μmol/L, respectively), and a corresponding damage was observed in the comet assay (median of DNA percentage in tail: 27.37 vs. 0.31, respectively). However, we found poor correlation between urinary MDA and genetic damage (r <0.11). Conclusion: No evidence was obtained indicating that higher concentrations of MDA in urine were related to additional genetic damage, but there were more DNA damage and higher concentrations of MDA in individuals occupationally exposed to mercury compared with unexposed people.RESUMEN: Determinar si la magnitud del daño en el ADN se correlaciona con la concentración de malondialdehído (MDA) urinario en individuos expuestos ocupacionalmente a mercurio y en controles no expuestos. Metodología: se evaluaron 64 historias clínicas (32 de expuestos y 32 de controles) en los que se determinó la concentración urinaria de MDA y se hizo el ensayo cometa para detectar el porcentaje de ADN en la cola. Se compararon las concentraciones de MDA y las alteraciones en el cometa entre los grupos y se hizo una correlación entre estas variables. Resultados: hubo mayores concentraciones de MDA en los expuestos que en los controles (mediana 1,28 frente a 0,51 μmol/L, respectivamente), así como mayores daños en el ensayo cometa (mediana del porcentaje de ADN en cola: 27,37 frente a 0,31, respectivamente). Hubo mala correlación entre el MDA en la orina y el daño genético (r <0,11). Conclusión: no se pudo demostrar que a mayores concentraciones de MDA en la orina se presentara mayor daño genético, pero sí hubo mayor daño del ADN y concentraciones más altas de MDA en los expuestos que en los controles

Caffeinated energy drinks: neurological and cardiovascular effects

Energy caffeinated beverages are composed mainly of caffeine, carbohydrates and dietary supplements. Although manufacturers claim that these drinks are safe and many consumers perceive that also, there is concern about the possibility that adverse events may occur with their consumption. This led us to review the literature with emphasis on the cardiovascular and neurological risks. It was found that the major health complaints (headache, sleep disorders, irritation and fatigue) were more frequent in consumers than in non-consumers. Emergency room visits motivated by the use of energy drinks were more frequent when there was co-ingestion of ethanol and other drugs. The main cause of cardiovascular emergency consultation was arrhythmia and the neurological one, seizure. The evidence found was of poor quality, which prevented establishing a causal link between the consumption of these drinks and such risks. On the other hand, interpretation of the toxicity of these preparations is complicated because several variables should considered such as dose, individual sensibility, consumption habits, smoking, and co-ingestion of other substances, etc., in order to assess their real risk. Despite this, concomitant consumption of these beverages and ethanol seems to be a risk factor for toxicity

Association between Concentrations of Malondialdehyde (MDA) and Neurological Abnormalities in People Occupationally Exposed to Mercury

It is believed that mercury neurotoxicity is due to induction of oxidative stress [as determinedby increased concentrations of malondialdehyde (MDA)], but we don’t know if to have higherconcentrations of MDA involves to have more neurological disorders. Objective: To establish associationbetween urinary concentrations of MDA and the severity of neurological abnormalitiesin people exposed to mercury. Materials and methods: A cross-sectional study was done. Inclusioncriteria: men between 18 and 60 years with occupational exposure to metallic mercury. Thesample was taken from a database of 110 patients exposed to mercury. Information was gatheredfrom medical records with emphasis on neurologic outcome, from the mercury concentration inurine of 24 hours and from urinary MDA analysis. For statistical analysis, nonparametric testswere used for comparisons between concentrations of MDA among those with neurologicaldisorders vs. those without disorders and to evaluate differences in the concentrations of thissubstance according to the severity of these alterations; it was performed correlation analysisbetween urinary concentrations of MDA and urinary concentrations of mercury. Results: Theconcentrations of MDA in patients exposed to mercury with neurological abnormalities were notdifferent from those without abnormalities. MDA concentrations neither were associated withthe severity of clinical findings. There was no correlation between MDA and urinary mercuryconcentrations. Conclusion: It will be necessary to search biological samples other than urinethat could reflect what occurs in CNS or look for other pathophysiological causes to explain thepresence of clinical findings in these patients

Correlation between urinary concentrations of malondialdehyde and DNA damage in people exposed to mercury = Correlación entre la concentración urinaria de malondialdehído y daño en el ADN de personas expuestas a mercurio

Objective: To determine whether the extent of DNA damage is correlated with the concentration of malondialdehyde (MDA) in urine of individuals occupationally exposed and unexposed to mercury Methods: We evaluated 64 medical records (32 reference group and 32 exposed group, they were matched byage, smoke and alcohol consumption). For analysis, comet assay data (olive tail moment, % DNA in the tail and tail length), levels of urinary MDA and urinary mercury were taken. We compared the concentrations of MDA and the changes in the comet assay between the groups and the correlation between these variables. Results: MDA concentrations were higher in exposed than in referents (median 1.28 vs 0.51μmol/L, respectively) and further damage to the comet assay (mean of tail % DNA: 27.37 vs. 0.31, median of Olivetail moment 8.29 vs olive 0.056; median of tail length 35 vs. 3.0, respectively).However there was a poor correlation between urinary MDA and genetic damage(r<0.11). Conclusion: No evidence was obtainedwith higher concentrations of MDA in urine provide additional genetic damage, but there was more DNA damage and higher concentrations of MDA in individuals occupationally exposed to mercury

Associação entre concentração de malondialdeído (MDA) e anormalidades neurológicas em pessoas ocupacionalmente expostoa ao mercúrio

Se cree que la neurotoxicidad por mercurio metálico se debe a la inducción del estrés oxidativo (determinado por aumento de las concentraciones de malondialdehído, MDA), pero se desconoce si la mayor concentración de MDA implica mayor cantidad de alteraciones neurológicas. Objetivo: establecer la asociación entre las concentraciones urinarias de MDA y la gravedad de la neurotoxicidad en individuos expuestos a mercurio. Materiales y métodos: se recurrió a un estudio transversal. Se incluyeron hombres entre 18 y 60 años laboralmente expuestos a mercurio. Se tomaron 110 unidades de análisis de una base de datos. Se obtuvo información de historias clínicas con énfasis en la evolución neurológica, de la concentración de mercurio en orina de 24 horas y de análisis de MDA en orina. Se compararon concentraciones de MDA entre quienes tenían alteraciones neurológicas contra quienes no las tenían y se evaluaron las diferencias de las concentraciones de esta sustancia de acuerdo con la gravedad neurológica; se realizó un análisis de correlación entre concentraciones urinarias de MDA con las concentraciones urinarias de mercurio. Resultados: como resultado se obtuvo que las concentraciones de MDA en los individuos expuestos a mercurio y que presentaron alteraciones neurológicas no fueron diferentes de las concentraciones de los individuos expuestos pero sin alteraciones neurológicas. Sus concentraciones tampoco estuvieron asociadas con la gravedad. No hubo correlación entre las concentraciones urinarias de MDA y mercurio. Conclusión: será necesario buscar otras muestras biológicas diferentes a la orina que reflejen lo que ocurre en el sistema nervioso central (SNC), o buscar otras razones fisiopatológicas que expliquen la presencia de las manifestaciones clínicas en estos individuos.It is believed that mercury neurotoxicity is due to induction of oxidative stress [as determined by increased concentrations of malondialdehyde (MDA)], but we don’t know if to have higher concentrations of MDA involves to have more neurological disorders. Objective: To establish association between urinary concentrations of MDA and the severity of neurological abnormalities in people exposed to mercury. Materials and methods: A cross-sectional study was done. Inclusion criteria: men between 18 and 60 years with occupational exposure to metallic mercury. The sample was taken from a database of 110 patients exposed to mercury. Information was gathered from medical records with emphasis on neurologic outcome, from the mercury concentration in urine of 24 hours and from urinary MDA analysis. For statistical analysis, nonparametric tests were used for comparisons between concentrations of MDA among those with neurological disorders vs. those without disorders and to evaluate differences in the concentrations of this substance according to the severity of these alterations; it was performed correlation analysis between urinary concentrations of MDA and urinary concentrations of mercury. Results: The concentrations of MDA in patients exposed to mercury with neurological abnormalities were not different from those without abnormalities. MDA concentrations neither were associated with the severity of clinical findings. There was no correlation between MDA and urinary mercury concentrations. Conclusion: It will be necessary to search biological samples other than urine that could reflect what occurs in CNS or look for other pathophysiological causes to explain the presence of clinical findings in these patients.Acredita-se que a neurotoxicidade do mercúrio metálico devido à indução de estresse oxidativo [conforme determinado pelo aumento das concentrações de malondialdeído (MDA)], mas não sabe se quer ter maiores concentrações de MDA envolve mais alterações neurológicas. Objetivo: estabelecer a associação entre a concentração urinária do MDA e da gravidade da neurotoxicidade em expostos ao mercúrio. Materiais e métodos: Estudo transversal. Ele incluiu homens entre 18 e 60 expostos ao mercúrio. Levou 110 unidades de análise de um banco de dados. As informações foram coletadas dos prontuários médicos, com ênfase na evolução neurológica, a concentração de mercúrio na urina de 24 horas e MDA na análise da urina. Testes não paramétricos foram utilizados para comparar as concentrações de MDA em pacientes com distúrbios neurológicos vs aqueles que não tê-los e avaliar as diferenças na concentração desta substância em função da gravidade dos distúrbios, foi feita uma análise de correlação entre as concentrações urinárias MDA com concentrações urinárias de mercúrio. Resultados: As concentrações de MDA no exposto a alterações de mercúrio e neurológico não foram diferentes daquelas expostas, mas sem distúrbios neurológicos. Seus níveis não foram associados com a gravidade. Não houve correlação entre o MDA e concentrações urinárias de mercúrio. Conclusão: Será necessário procurar outras amostras biológicas de urina que não reflectem o que ocorre no SNC ou procurar outras razões fisiopatológicas explicar a presença das manifestações clínicas nesses indivíduos