Biomarcadores moleculares para evaluar el riesgo para la salud debido a la exposición a contaminantes ambientales

Biomarkers, or bioindicators, are metric tools that, when compared with reference values, allow specialists to perform risk assessments and provide objective information to decision makers to design effective strategies to solve health or environmental problems by efficiently using the resources assigned. Health risk assessment is a multidisciplinary exercise, and molecular biology is a discipline that greatly contributes to these evaluations because the genome, transcriptome, proteome and metabolome could be affected by xenobiotics causing measurable changes that might be useful biomarkers. Such changes may greatly depend on individual genetic background; therefore, the polymorphic distribution of exposed populations becomes an essential feature for adequate data interpretation. The aim of this paper is to offer an up-to-date review of the role of different molecular biomarkers in health risk assessments.Los biomarcadores, o bioindicadores, son herramientas métricas que, al compararse con los valores de referencia, permiten evaluar los riesgos y generar información objetiva que ayude a las autoridades a planificar estrategias efectivas, solucionar problemas de salud o ambientales y utilizar los recursos asignados de manera eficiente.La evaluación de riesgos en salud es un ejercicio multidisciplinario y la biología molecular contribuye enormemente a estos estudios, dado que el genoma, el transcriptoma, el proteoma y el metaboloma pueden verse afectados por xenobióticos, lo que causa cambios cuya medición resulta útil en la adopción de decisiones. Dichos cambios pueden variar por la carga genética de cada individuo y su distribución polimorfa en las poblaciones expuestas se convierte en un factor esencial para una adecuada interpretación de resultados.Por lo tanto, el objetivo del presente artículo fue hacer una revisión de los diferentes biomarcadores moleculares aplicables a la evaluación de riesgos para la salud provenientes de los contaminantes ambientales

Some Acute Effects of Arsenic On The Liver.

The livers of rats dosed acutely with As III developed a lipid vacuolation of the periportal area, a general loss of glycogen, dilation of the bile canaliculi, and various degrees of mitochondrial condensation. These morphological changes were more evident in phenobarbitone pretreated rats.As III induced hepatic haem oxygenase activity, regardless of the pretreatment. This induction was reflected by an increase in the excretion of bilirubin 6 hr after treatment. The source of haem being degraded was investigated by injecting rats with 5- amino-[4- 14C]-laevulinic acid. The radioactive label was excreted before the bulk of the bilirubin, suggesting that hepatic haem was the first to be degraded. The excretion of haem is presumably due to haemoglobin breakdown, since immunoelectrophoresis show haptoglobin to be increased in the bile of As III rats. Cytochrome P-450 levels and ethoxycoumarin-O-deethylase activity gradually decreased with time after As III administration. The effect appears to be isoenzyme non-specific because As III administration to phenobarbitone pretreated rats significantly decreased pentoxyresorufin-O-deethylase, benzphetamine-N-demethylase, and ethoxyresorufin-O-deethylase activities, but did not significantly affect ethoxycoumarin-O-deethylase . In vitro, and at high concentrations, As III produced no change in the rat liver microsomal cytochrome P-450 content, but produced a fall in cytochrome concentration when NADPH was added. No effect was found at concentrations likely to be present in vivo. Hence, it appears that As III may bind apo-cytochrome P-450, rather than holo-cytochrome P-450, and as a consequence of this, the "free" haem pool increases, triggering the induction of HO

Low-Intensity Pulsed Ultrasound Effect on MIO-M1 Cell Viability: Setup Validation and Standing Waves Analysis

Low-intensity pulsed ultrasound (LIPUS) has been proposed for novel therapies still under study, where similar parameters and protocols have been used for producing opposite effects that range from increasing cell viability to provoking cell death. Those divergent outcomes make the generalization of expected effects difficult for cell models not yet studied. This paper presents the effect of LIPUS on the viability of the MIO-M1 cell line for two well-established setups and different protocols; the acoustic intensities, duty factors, and treatment duration were varied. Measurements and models for acoustic and thermal analysis are included for proposing a solution to improve the reproducibility of this kind of experiments. Results indicate that MIO-M1 viability is less affected for the cells treated through a dish that is partially immersed in water; in these conditions, the cells neither show detrimental nor proliferative effects at intensities lower than 0.4 W/cm2 at 20% duty factor. However, cell viability was reduced when LIPUS was followed by cell subculturing. Treating the cells through a gel, with the culture dish placed on the transducer, increases cell mortality by the production of standing waves and mixed vibration-acoustical effects. Using the water-based setup with a 1° dish inclination reduces the effects of standing waves