Watercress (Nasturtium officinale, Cruciferae; W. Aiton) is a vegetable widely consumed in our country, with nutritional and potentially chemopreventive properties. Previous reports from our laboratory demonstrated the protective effect of watercress juice against DNA damage induced by cyclophosphamide in vivo. In this study, we evaluated the in vivo effect of cress plant on the oxidative stress in mice. Animals were treated by gavage with different doses of watercress juice (0.5 and 1g/kg body weight) for 15 consecutive days before intraperitoneal injection of cyclophosphamide (100 mg/kg body weight). After 24 h, mice were killed by cervical dislocation. The effect of watercress was investigated by assessing the following oxidative stress biomarkers: catalase activity, superoxide dismutase activity, lipid peroxidation, and glutathione balance. Intake of watercress prior to cyclophosphamide administration enhanced superoxide dismutase activity in erythrocytes with no effect on catalase activity. In bone marrow and liver tissues, watercress juice counteracted the effect of cyclophosphamide. Glutathione balance rose by watercress supplementation and lipid oxidation diminished in all matrixes when compared to the respective control groups. Our results support the role of watercress as a diet component with promising properties to be used as health promoter or protective agent against oxidative damage.

El berro (Nasturtium officinale, crucíferas; W. Aiton) es una hortaliza ampliamente consumida en nuestro país, con valor nutricional y propiedades potencialmente quimiopreventivas. En trabajos previos demostramos que el jugo de berro tiene efecto protector in vivo contra el daño del ADN inducido por ciclofosfamida en tejidos del ratón. En el presente trabajo evaluamos, también in vivo, los efectos del jugo sobre el estrés oxidativo en diferentes tejidos del ratón. Los siguientes biomarcadores fueron investigados: actividad de superóxido dismutasa, actividad de catalasa, peroxidación lipídica y balance de glutatión. Los animales fueron tratados con diferentes dosis de jugo (0.5 y 1 g/kg de peso corporal) por alimentación forzada durante 15 días consecutivos antes de la inyección intraperitoneal con ciclofosfamida (100 mg/kg). La ingesta de berro antes de la administración de ciclofosfamida mejoró la actividad de superóxido dismutasa en los eritrocitos sin efecto sobre la actividad de la catalasa. En médula ósea e hígado, el jugo de berro contrarrestó el efecto deletéreo de la ciclofosfamida. En todas las matrices, el balance de glutatión fue mayor y la oxidación de lípidos menor que los valores encontrados en los grupos control. Nuestros resultados demuestran que el berro es un componente de la dieta con propiedades prometedoras como promotor de la salud o como agente protector contra el daño oxidativo.

Introduction. Obesity is associated with a wide range of cardiovascular and metabolic diseases. Objective. To establish an association between the nutritional status of 6-10 year old boys and girls and blood pressure. Population and Methods. A cross-sectional, analytical study was conducted in 6-10 year old schoolboys and schoolgirls. Outcome measures and indicators studied included nutritional status as per body mass index; presence of central fat mass distribution estimated by waist circumference; and blood pressure (height, age and gender tables). Differences in mean values were analyzed using a Student's t test. The relationship between outcome measures was estimated using Pearson's correlation coefficient. Linear regression models were adjusted for systolic blood pressure and diastolic blood pressure using the following explanatory outcome measures: z scores for body mass index, age, gender and waist circumference. Results: Five hundred and fifty five male and female children were evaluated; they were all younger than 11 years old. A total of 26.3% was overweight and 15.1% was obese. The prevalence of hypertension was 1.08%. Results show a positive linear relationship between systolic and diastolic blood pressure, and age and waist circumference, and a trend is observed between systolic blood pressure and the body mass index z score (p= 0.068). Conclusion. Overweight and obesity were the most common nutritional disorders in schoolaged children in the studied district; there is an association between age, waist circumference, and systolic and diastolic blood pressure, and between systolic blood pressure and the body mass index z score.

Pesticides are used in agriculture to protect crops but may represent a potential risk to farmers and the environment. The aim of this work was to evaluate horticultural workers exposed to pesticide, categorized by: direct exposure (n = 45), indirect exposure (n = 50) and controls (n = 50) using exposure and effect biomarkers: cholinesterase (ChE), acetylcholinesterase (AChE), catalase (CAT), lipid peroxidation (TBARS), Damage Index Comet Assay (IDEC) and Damage Index Repair Assay (IDER). Our results show: a) an AChE inhibition in directly and indirectly exposed population (p < 0.001), b) significant increase in the levels of TBARS in direct exposure (p < 0.001), c) the CAT reduction was significant (p < 0.01), d) a significant increase in IDEC and IDER in both exposed groups (p < 0.001). Our results evidence variations in oxidative balance and DNA damage in exposed workers. These findings represent a contribution to the sub-clinical evaluation of subjects exposed to agrochemicals in our country.

Los pesticidas utilizados en agricultura pueden representar un riesgo potencial para la salud de los agricultores expuestos y para el medio ambiente. El objetivo de este trabajo fue evaluar trabajadores frutihortícolas expuestos a plaguicidas, categorizados por: exposición directa (n = 45), exposición indirecta (n = 50) y controles (n = 50) mediante biomarcadores de exposición y efecto: colinesterasa (ChE), acetilcolinesterasa (AChE), catalasa (CAT), peroxidación de lípidos (TBARS), Indice de Daño Ensayo Cometa (IDEC) e Indice de Daño Ensayo Reparación (IDER). Los resultados indican: a) inhibición significativa de AChE (p < 0.001) en expuestos directos e indirectos; b) aumento en los niveles de TBARS (p < 0.001) en los directos; c) reducción de CAT significativa (p < 0.01) y d) aumento de IDEC e IDER (p < 0.001) en ambos grupos. Los resultados obtenidos reflejan modificaciones en el balance oxidativo junto con daño al ADN en los trabajadores estudiados. Estos hallazgos representan una contribución en la evaluación subclínica de exposición a agroquímicos en nuestro país.

The aim of the present work was to describe the distribution of lymphocyte P-glycoprotein activity on a population of healthy individuals, taking also into account sex and age. P-glycoprotein activity in lymphocytes was measured by the Rhodamine 123 efflux assay using flow cytometry, in the presence and absence of verapamil, a P-glycoprotein inhibitor. We obtained a range of P-glycoprotein activity from 1.04 to 3.79. The distribution of the activity in the population studied was better described by a bimodal model, according with the Kolmogorov-Smirnov test. The frequency adjusted to the following equation: F = 0.70 N (2.11; 0.43) + 0.30 N(3.29; 0.26), in which 0.70 and 0.30 represented the proportion of each group, and 0.43 and 0.26 were the standard deviations of the activity of each group, respectively. The study of the relationship between subjects´ age and P-glycoprotein activity showed no statistical significance. When healthy volunteers were separated according to sex, similar distributions were observed, although for men an increase in proportion of higher P-glycoprotein function group was observed. The variability observed in the population studied was important, with some volunteers with very scarce activity and some with a fourfold higher activity. Characterization of P-glycoprotein functionality in the population represents a useful contribution to the beginning of pharmacological treatments that consider its effect on pharmacokinetics and pharmacodynamics of individualized patients.

El objetivo del presente trabajo fue describir la distribución de la actividad de la glicoproteína P linfocitaria en una población de individuos sanos, considerando a su vez el sexo y la edad. La funcionalidad de la glicoproteína P fue determinada mediante el ensayo de eflujo de Rodamina 123, en presencia y ausencia de verapamilo, un inhibidor competitivo de este transportador, determinando la fluorescencia intracelular remanente mediante citometría de flujo. Obtuvimos un rango de actividades de entre 1.04 y 3.79. La distribución de la actividad en la población evaluada se ajusta a un modelo bimodal, según el test de Kolmogorov-Smirnov. La frecuencia ajusta a la siguiente ecuación: F = 0.70 N (2.11; 0.43) + 0.30 N (3.29; 0.26) donde 0.70 y 0.30 representan las proporciones de cada grupo, mientras que 0.43 y 0.26 corresponden al desvío estándar de la actividad de cada grupo respectivamente. Al estudiar la correlación entre la edad de los sujetos y la función de la proteína, no se observaron diferencias significativas. Cuando los individuos fueron clasificados en función del sexo, las distribuciones obtenidas fueron semejantes, aunque para los varones se observó un aumento en la proporción de individuos con alta actividad. La variabilidad observada fue importante, comprendiendo individuos con escasa actividad y otros que presentaron una actividad hasta cuatro veces mayor. La caracterización de la función de la glicoproteína P en la población representa una contribución indispensable para el desarrollo de tratamientos farmacológicos personalizados que consideren el efecto de dicho transportador en la farmacocinética y farmacodinámica de cada paciente.

P-glycoprotein (P-gp), encoded by MDR-1, is a transmembrane efflux pump that has been involved in relevant clinical drug transport. It is expressed in lymphocytes, luminal epithelium of colon and other tissues with barrier function. MDR1 was proposed as a candidate gene for ulcerative colitis. The aim of the present work was to investigate the role of P-gp in therapeutic response of ulcerative colitis by studying its functionality in lymphocytes isolated from peripheral blood. Samples were taken from 27 patients with active colitis classified clinically in refractory (n = 16) and responders (n = 11) to treatment. Rhodamine 123 (a fluorescent P-glycoprotein substrate) efflux was studied by flow cytometry as absence and presence of an inhibitor (verapamil, 100 μM). Data were expressed evaluating the behaviour of two markers defined based on % of cells with maximum (M1)/minimum (M2) intracellular fluorescence, reflecting inactivity/activity of the pump. Results were compared with a group of healthy individuals (n = 68). Significant differences were observed in absence and presence of Verapamil inhibition, when comparing refractory vs. responders (p < 0.05) as well as refractory vs. healthy controls (p 0.05) (Kruskal-Wallis test and Dunn post-test). Rhodamine efflux assay was also performed in 12 patients who required therapeutic change; a significant diminish of rhodamine transport (p < 0.01) was observed without inhibitor when patients achieved clinical response. Finally, our results suggest a possible relevant role of P-gp in ulcerative colitis treatment response and a possible usefulness of P-gp functional assay in the early detection of individual therapeutic response.

La glicoproteína gp-P, codificada por el MDR1 es una bomba de eflujo transmembrana capaz de movilizar una gran cantidad de fármacos de uso frecuente. Se expresa en la cara luminal del epitelio intestinal, en linfocitos y otros tejidos con función de barrera. MDR1 ha sido postulado como gen candidato en la colitis ulcerosa. El objetivo del presente trabajo fue evaluar la función de la gp-P en linfocitos aislados de sangre periférica de pacientes con colitis en actividad (n = 27) clasificados clínicamente como refractarios (n=16) o respondedores (n = 11) al tratamiento. Se estudió el eflujo de rodamina 123, sustrato de la glicoproteína P, en ausencia y presencia del inhibidor verapamilo (100 μM) determinando la fluorescencia intracelular por citometría de flujo. Los resultados se expresaron evaluando el comportamiento de dos marcadores que corresponden al % de células que contienen máxima (M1)/mínima (M2) concentración del colorante, reflejando inactividad/actividad de la bomba. Utilizando el test de Kruskal-Wallis y post test de Dunn, se observaron diferencias significativas entre refractarios versus respondedores (p < 0.05) y versus controles sanos (n = 68) previamente estudiados (p 0.05). Al mismo tiempo, se realizó el ensayo de eflujo en 12 pacientes que requirieron cambio de tratamiento, observándose una disminución significativa (p < 0.01) en el transporte de rodamina en ausencia de inhibidor una vez conseguida la mejoría clínica. En conclusión, los resultados sugieren un posible papel de la gp-P en la refractariedad y una posible utilidad de este método en la predicción de la respuesta individual al tratamiento farmacológico.

The mouse (Mus musculus) bone marrow micronucleus test was carried out using 24 outbred National Institutes of Health (NIH) mice, 24 inbred Swiss Webster (CFW) mice and 20 inbred Bagg albino/color locus Jackson (BALB/cJ) mice. The mice in the experimental group (n = 32) were injected intraperitoneally with 133 mg kg-1 of metronidazole parenteral solution and the control group consisted of mice (n = 36) which had not been injected with metronidazole. There was no significant difference (p > 0.05) between the sexes regarding the micronucleus frequency in either the experimental or the control group. When the Mn frequencies of the three strains were compared, the results for the CFW and BALB/cJ strains did not differ statistically (p > 0.05) for either the experimental or control groups but there were significant (p < 0.05) differences between the CFW and NIH strains and the NIH and BALB/cJ strains for the experimental and control groups, with the NIH strain always showing the highest micronucleus frequency. Our results also show that metronidazole was possible genotoxic agent because it produced a significant increase (p < 0.05) in the micronucleus frequency of the experimental group as compared to the control group for all the three mouse strains tested.