RESUMO
The toxicity of Roundup Original® (GLY), a glyphosate-based herbicide widely used in crops in Mato Grosso state, was determined in hybrid fish jundiara or pintado da Amazônia. The 96 h-LC50 of GLY was 13.57 mg L-1. Moreover, exposure to sublethal concentrations of GLY (0, 0.37, 0.75, 2.25, 4.5, 7.5 mg L-1) has not altered the survival rate (100% for all treatments). In fish liver, protein carbonyl (PC) levels as well as glutathione-S-transferase (GST) activity, reduced glutathione (GSH), and ascorbic acid (ASA) contents increased when compared to control group. Superoxide dismutase (SOD) activity was reduced and catalase (CAT) has not changed. PC content has grown in muscle and brain, and thiobarbituric acid-reactive species (TBARS) levels also increased in muscle, but in the brain, they remained unaltered. Acetylcholinesterase (AChE) activity reduced in muscle but increased in brain when compared to control group. Our results suggest that short-term exposure to GLY induced alterations in the oxidative stress biomarkers in fish and can be interfering with their survival in natural environment; besides, these findings may be considered of high ecotoxicological relevance.
Assuntos
Encéfalo/efeitos dos fármacos , Peixes-Gato/crescimento & desenvolvimento , Glicina/análogos & derivados , Herbicidas/toxicidade , Fígado/efeitos dos fármacos , Músculos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Ácido Ascórbico/metabolismo , Biomarcadores/metabolismo , Encéfalo/metabolismo , Catalase/metabolismo , Peixes-Gato/metabolismo , Glicina/toxicidade , Fígado/metabolismo , Músculos/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Tiobarbitúricos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , GlifosatoRESUMO
Roundup Original® is an herbicide widely used in Mato Grosso's agriculture and it may contamine water bodies, being an unforeseen xenobiotic to aquatic organisms, particularly fish. This study investigated the effects on the hybrid fish jundiara (Leiarius marmoratus×Pseudoplatystoma reticulatum) of an environmentally relevant exposure to this herbicide. Glucose levels in liver, muscle and plasma decreased after exposure to 1.357mgL-1 of Roundup Original® (glyphosate nominal concentration), while glycogen levels reduced in liver and muscle for different times. Elevated cholesterol and triglycerides revealed an adaptive response. Protein and lactate levels also increased during the experiment, however no changes were observed for muscle lactate. Increment of the transaminases suggests damage to the liver cells. After 96hours of exposure, reductions in all hematological parameters were observed, whereas the micronucleus test findings showed genotoxic scenery. Histological analysis did not display pathological alterations of the hepatic tissue. The results obtained provide valuable data for noticing the effects of pollutants on non-target organisms.