A redox proteomic investigation of oxidative stress caused by benzoylecgonine in the freshwater bivalve Dreissena polymorpha

Abstract

Drugs of abuse and their human metabolites have been recently recognized as emerging environmental contaminants. Notwithstanding the fact that these kinds of compounds share some features with pharmaceuticals, their ecotoxicology has not yet been extensively investigated, although some of their characteristics may potentially threaten aquatic ecosystems. One of the most abundant drugs found in rivers and wastewaters is benzoylecgonine (BE), the main metabolite of cocaine. We applied a redox proteomics approach to evaluate changes in the proteome of Dreissena polymorpha exposed to two different concentrations of BE (0.5 and 1 µg/l). Exposures were performed in vivo for a period of 14 days and the effect of oxidative stress on protein thiol and carbonyl groups in mussel gills were evaluated. One-dimensional electrophoresis did not reveal a reduction in protein thiol content but showed a significant increase of protein carbonylation at both doses tested. Then, protein profiling using two-dimensional gel electrophoresis was performed with subsequent matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) and TOF/TOF with LIFT technique and linear ion trap combined with orbitrap mass spectrometer (LTQ-Orbitrap). This yielded de novo protein sequences suitable for database searching. These preliminary results and protein identifications obtained suggest that BE causes oxidative stress. Oxidative modifications were detected in differing classes of proteins such as those of the cytoskeleton, energetic metabolism and stress response.

Removal of benzoylecgonine from water matrices through UV254/H2O2 process: Reaction kinetic modeling, ecotoxicity and genotoxicity assessment

“…Considering an ACR equal to 10 3 and the EC50 of BE on nematodes evaluated in this work (0.6 ppm), a chronic toxic effect could be observed on nematodes at the BE concentration equal to 0.6 ppb. The predicted MATC value is in agreement with the results previously reported [13][14][15] regarding the negative effect of BE contaminated water solutions (0.5 and 1.0 ppb) on Dreissena polymorpha. Moreover, the ecotoxicity and genotoxicity tests carried out with the sample withdrawn at tf suggest, considering the same ACR value, that it is possible that the by-products, deriving by the UV 254 /H 2 O 2 , treatment of a solution containing BE at the concentration of 1 ppb, could exert a negative chronic effect on living organisms.…”

“…(15)(16) Figure 4 show a robust prediction capability by the model of the experimental results even though the reactor geometry radically changed in comparison to the MCF.…”

“…The exposure of freshwater mussel, Dreissena polymorpha, to BE contaminated water solutions (0.5 and 1.0 ppb), yielded a 3.5-fold increase in oxidative stress and increased or inhibited antioxidant and detoxifying enzymes activity depending on BE levels and exposure time [13][14][15].…”

Ecotoxicological Risk of Personal Care Products and Pharmaceuticals

“…Differential protein expression signatures in the digestive gland of Mytilus spp. Moreover exposure of D. polymorpha to benzoylecgonine (main metabolite of cocaine) (0.5 and 1 μg L −1 ) for 2 weeks revealed an increase in protein carbonylation and oxidative stress translated by modifications in cytoskeleton, energetic metabolism, and stress response proteins in gills (Pedriali et al, 2013). Seven were identified by liquid chromatography-tandem mass spectrometry and indicated changes in proteins involved in energy metabolism, oxidative stress response, protein folding, and immune responses (Schmidt et al, 2013).…”

Perturbation of xenobiotic metabolism in Dreissena polymorpha model exposed in situ to surface water (Lake Trasimene) purified with various disinfectants

“…Zebra mussels have both inhalant and exhalant siphons and are capable of filtering about 1 L of water per day, while feeding primarily on algae. D. polymorpha has recently become an environmental biomarker, widely used for several pollutants in lake or marine waters (Fern andez-Sanjuan et al, 2013;Johns, 2012;Minguez et al, 2011;Pedriali et al, 2013).…”