RESUMEN
Boca de Camichin Estuary is one of the main producers of Crassostrea corteziensis oysters in Mexico, but the presence of pollutants can affect oyster production. Molluscs produce reactive oxygen species (ROS) in response to changes in the environment and pollution. These ROS induce oxidative damage in biomolecules. The main objective of this study was to evaluate pollution in the estuary and the subsequent oxidative stress in C. corteziensis oysters during the 2010 production cycle. For this aim, we performed monthly samplings in the oyster farms from January to May. We took water samples to quantify polycyclic aromatic hydrocarbon (PAH) and metal content; also, we evaluated oxidative damage (lipoperoxidation, lipidic hydroperoxides, protein oxidation) and enzyme activity (CAT, SOD, GPx, GST and AChE) in oyster gills. The results show the presence of Cu, Fe, Mn, naphthalene, benz[a]anthracene, pyrene, benz[a]pyrene and benzo[k]fluoranthene. On the other hand, AChE activity was not inhibited, which suggests that organophosphorus pollutants or carbamates were absent. Regarding oxidative stress, oysters from the estuary had oxidative damage in lipids, not proteins, and altered antioxidant enzyme activity, when compared to control organisms. Interestingly, we did not observe any correlation between the pollutants and the oxidative stress parameters evaluated in this study. Thus, we cannot rule out that a synergistic effect between the environmental variables and the pollutants is causing the oxidative stress in these oysters.
Asunto(s)
Crassostrea/metabolismo , Estuarios , Estrés Oxidativo , Contaminantes Químicos del Agua/metabolismo , Contaminación del Agua/análisis , Acetilcolinesterasa/metabolismo , Animales , Catalasa/metabolismo , Cobre/metabolismo , Cobre/toxicidad , Crassostrea/efectos de los fármacos , Monitoreo del Ambiente/métodos , Geografía , Branquias/efectos de los fármacos , Branquias/metabolismo , Glutatión Peroxidasa/metabolismo , Hierro/metabolismo , Peróxidos Lipídicos/metabolismo , Manganeso/metabolismo , Manganeso/toxicidad , Metales/metabolismo , Metales/toxicidad , México , Naftalenos/metabolismo , Naftalenos/toxicidad , Hidrocarburos Policíclicos Aromáticos/metabolismo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Estaciones del Año , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/toxicidadRESUMEN
The physiological system of molluscs, particularly pro-oxidant and antioxidant mechanisms, could be altered by pollutants and induce disturbance on health status and productive parameters of aquatic organisms, such as oyster. Therefore, the aim of this study was to evaluate the chemical contamination in water (total metals and polycyclic aromatic hydrocarbons) and oxidative stress parameters in oysters (Crassostrea corteziensis) in Camichin estuary, located in Mexican Tropical Pacific. The results obtained showed the presence of arsenic, lead and zinc, as well as naphthalene, pyrene and benzo[a]pyrene in concentrations relatively higher than criteria established by local and international guidelines. Regarding the biomarkers of oxidative stress response (H2O2 and O2 concentration, catalase activity, lipid peroxidation, and hydroperoxide concentration), differences between oyster from estuary and control group were significant. These results indicate that these pollutants could be related with oxidative stress detected in oyster.
Asunto(s)
Antioxidantes/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Contaminantes Químicos del Agua , Animales , Monitoreo del Ambiente , Estuarios , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido , México , Ostreidae/efectos de los fármacos , Ostreidae/metabolismoRESUMEN
The effect of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide), an organochlorine pesticide, was evaluated on phagocytic (phagocytic index and percentage of active cells) and hematological parameters in Nile tilapia. Experimental data showed that an acute exposure to endosulfan (4.0 and 7.0 microg/L) induces a significant decrease in the phagocytic index and the percentage of active cells in peripherical blood of Nile tilapia. However, hemoglobin concentration (Hb), hematocrit (Hto), red blood cell count (RBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were not significantly altered in fish exposed to endosulfan compared with control group.