Immuno-endocrine alterations and oxidative stress induced by commercial formulations of pesticides in the tegu lizard (Salvator merianae).

Recent research has shown the risk of environmental contamination by pesticides in Argentina. Salvator merianae is considered as "sentinel species" for monitoring their effects. We intended to investigate growth, immunological and endocrine functions, and oxidative stress in S. merianae exposed to two commercial brands of the herbicide glyphosate: Roundup and Panzer Gold, as well as, to two insecticides: chlorpyrifos, and cypermethrin. Our results showed a higher increase in growth in animals exposed to Roundup and chlorpyrifos and a lower increase in those exposed to Panzer Gold. Higher total leukocyte and lymphocyte count values were observed in lizards exposed to Panzer Gold. The heterophils/lymphocytes ratio decreased in all treated animals. Regarding lobularity index, natural antibodies titers, and complement system activity values, lizards exposed to cypermethrin had higher values. Low corticosterone levels were observed in animals exposed to Roundup. Our results reveal different toxic effects of pesticides contributing to the knowledge of the pesticides' potential deleterious impact in the habitat of S. merianae.

DNA damage and oxidative stress in gill cells of Cnesterodon decemmaculatus exposed to pesticides by runoff source in an agricultural basin.

In our country, great concern exists about diffuse pollution cause by the great use of pesticides in rural environments. A thorough analysis is needed to generate information, know the real situation and thus, be able to make decisions with the purpose of reducing environmental pollution. In situ bioassays have been carried out using Cnesterodon decemmaculatus within limnocorrals located in a surface natural water system that receives rainfall excess flowing from an agricultural basin with a typical crop rotation, including corn, wheat and soy. Specimens were taken from the limnocorrals 72 h after a probed natural runoff event toward the water body, and the gill cells were used to evaluate the DNA damage (comet assay, CA), catalase enzyme activity (CAT), and lipid peroxidation (LPO). In addition, the physicochemical analysis of the water (pH, temperature) and the presence and concentration of pesticides were carried out. The results showed significant differences on DNA damage and oxidative stress on the gill cells of the exposed fish compared to controls, being the combination of the rain regime and the mixtures of pesticides used in corn and soy more toxic than in wheat. These results highlight the necessity to understand detrimental processes caused by pesticides used in extensive systems of primary production, in order to prevent and minimize diffuse contamination, contributing to environmental recovery and sustainability.

Evaluación de estrés oxidativo en pacientes con Lupus Eritematoso Sistémico y su posible relación con la exposición ambiental a agroquímicos / Assessment of oxidative stress in patients with Systemic Lupus Erythematosus and its possible relationship with environmental exposure to agrochemicals

Los agroquímicos son un método efectivo para controlar especies perjudiciales a los intereses del hombre, pero aplicados indiscriminadamente provocan diversos impactos a nivel ambiental y en la salud. Uno de los mecanismos más importantes por el cual los agroquímicos se ponen en contacto directo con las poblaciones de zonas periurbanas es mediante la deriva. El Lupus Eritematoso Sistémico (LES) es una enfermedad autoinmune que posee un amplio rango de presentaciones clínicas y severidad. Si bien su etiología es desconocida, se la asocia con diversas causas ambientales dentro de las que podrían estar presentes los agroquímicos. El objetivo de este estudio fue evaluar, el posible daño oxidativo generado por exposición ambiental a mezclas de agroquímicos en pacientes con LES y personas sanas que residen en zonas rurales expuestas a mezclas de plaguicidas y contrastar los resultados con pacientes y personas sanas de zonas urbanas no expuestas. Se evaluaron 44 pacientes con diagnóstico de LES y 58 personas sanas (controles), se utilizaron como marcadores: catalasa (CAT), superóxido dismutasa (SOD), la relación glutation oxidado/reducido (GSH/GSSG) y lipoperoxidación (TBARS). Se encontraron diferencias estadísticamente signifcativas para TBARS y SOD al comparar los resultados del grupo LES urbano con su control y el grupo LES rural con el suyo (p<0,01 en ambos). Al realizar las comparaciones entre LES urbano y LES rural se halló un incremento en TBARS del 18,3% (p=0,014). Esta investigación demuestra la importancia de la utilización de biomarcadores de daño oxidativo en el seguimiento clínico de pacientes con LES, con el fn de establecer pautas de tratamiento adecuadas y considerar la relación entre la exposición ambiental a plaguicidas y el aumento de daño oxidativo en pacientes con LES.

The agrochemicals are an effective method to control harmful species of interests to humans, but when they are applied indiscriminately, they can cause environmental and health damage to people. Systemic Lupus Erythematosus (SLE) is an autoimmune disease that has a wide range of clinical manifestations and severity. While the etiology of SLE is unknown, it is associated with various environmental causes, being one possibility the exposure to agrochemicals. The aim of this study was to evaluate the possible oxidative damage generated by environmental exposure to agrochemical mixtures in SLE patients and healthy people living in rural areas and compare them with patients and healthy people living in urban, unexposed areas. Forty four patients diagnosed with SLE and 58 healthy individuals (controls) were evaluated, using the following markers: Catalase (CAT), superoxide dismutase (SOD), the oxidized/reduced glutathione ratio (GSH / GSSG) and lipid peroxidation (TBARS). Statistically signifcant differences were found in TBARS and SOD by comparing the results of the urban SLE group with its control and rural SLE group with its control (p <0.01 for both cases). When making comparisons between urban SLE group and the rural SLE group, an increase of 18.3% was found in TBARS (p = 0.014). This research demonstrates the importance of using biomarkers of oxidative stress in the clinical monitoring of patients with SLE, in order to establish guidelines for appropriate treatment and consider the relationship between environmental exposure to pesticides and increased oxidative damage in patients with SLE.

Evaluación de genotoxicidad a través de la frecuencia de Micronúcleos en eritrocitos de Piaractus mesopotamicus (pacúes) expuestos in vivo a nanopartículas de plata / Assessment of genotoxicity by Micronucleus frequency in Piaractus mesopotamicus erythrocytes exposed to silver nanoparticles in vivo

El uso creciente de nanomateriales en productos industriales y de consumo ha incrementado la preocupación mundial respecto a sus posibles efectos adversos en los sistemas biológicos. Como consecuencia de la falta de un marco legislativo y la ausencia de un consenso sobre los protocolos experimentales, las investigaciones ecotoxicológicas se llevan a cabo a un ritmo mucho más lento que la producción de nuevas nanopartículas. Por esta razón, existe una necesidad creciente de realizar estudios que aporten conocimiento sobre el riesgo de estos contaminantes emergentes de propiedades únicas. El objetivo del presente trabajo fue evaluar la frecuencia de micronúcleos (FMN) en eritrocitos de ejemplares juveniles de pacú (Piaractus mesopotamicus) expuestos a nanopartículas de plata (Nano-Ag) a las concentraciones de 0 μg·L-1 (control); 2,5 μg·L-1; 10 μg·L-1; y 25 μg·L-1, durante 24 horas. Se observó que la FMN se incrementó significativamente (p<0,01) en la concentración de 25 μg·L-1, mientras que no hubo diferencias significativas entre los grupos expuestos a 2,5 y 10 μg·L-1 y el control. Estos resultados sugieren que los eventos aneugénicos o clastogénicos podrían representar un posible mecanismo de toxicidad de Nano-Ag en esta especie.

The growing use of nanomaterials in consumer and industrial products has aroused global concern about possible adverse effects on biological systems. Due to the lack of a regulation framework and the absence of a consensus on the experimental protocols, ecotoxicological investigations are carried out much slower than the production of new nanoparticles. For this reason, there is a growing need for studies that provide knowledge about the risk of these emerging contaminants of unique properties. The objective of the present study was to evaluate the frequency of micronuclei (FMN) in erythrocytes of juvenile Piaractus mesopotamicus exposed to silver nanoparticles (nano-Ag; Nanotek SA) at concentrations of 0 μg·L-1 (control); 2.5 μg·L-1; 10 μg·L-1; and 25 μg·L-1, for 24 hours (n = 10 per treatment). The FMN show a significant increase (p <0.01) in fish exposed to 25 μg·L-1 of Nano-Ag, while there were no significant differences among the groups exposed to 2.5 and 10 μg·L-1 with the control. These results suggest that the aneugenics or clastogenics events may represent a possible mechanism of toxicity of Nano-Ag in this specie.

Ultraviolet radiation on innate immunity and growth of broad-snouted caiman (Caiman latirostris): implications for facilities design.

Sunlight is a key environmental factor in almost all ecosystems, and it is necessary for many physiological functions. Many vertebrates require ultraviolet (UV) radiation to perform different physiological processes. Artificial light is used to supplement UV in captive animals, through appropriate photoperiods and UV wavelengths. Previous studies reported that repeated exposure to artificial UV radiation may cause damage to the immune system. Taking into account the importance of UV effects and the serum complement system, the relationship between them was investigated. The study lasted 90 days and was carried out in plastic chambers. Ninety six broad-snouted caiman (C. latirostris) were assigned to four treatment groups with two replicates each: total darkness (TD), 8 hr per day (8 hr) and 16 hr per day (16 hr) of artificial UV/visible light exposure, and normal photoperiod of natural light (NP). Snout-vent length was measured to determine animal growth. Hemolytic assays were performed to evaluate the effects of artificial UV/visible light, TD, and NP on the serum complement system. Results showed that animals grew more in the NP group. The capacity of C. latirostris serum to hemolyze sheep red blood cells was higher in the NP group than when they are maintained in constant light-dark cycles (8 and 16 hr) or in TD. These data demonstrate that artificial UV should be considered as a potential hazard for captive crocodilians if it is not properly managed, and this should be taken into account in the general design of facilities for reptilian husbandry.