RESUMO
Paraquat (PQ) has known negative human health effects, but continues to be commonly used worldwide as a herbicide. Our clinical data shows that the main prognostic factor is the time required to achieve a negative urine dithionite test. Patient survival is a 100% when the area affected by ground glass opacity is <20% of the total lung volume on high-resolution computed tomography imaging 7 days post-PQ ingestion. The incidence of acute kidney injury is approximately 50%. The average serum creatinine level reaches its peak around 5 days post-ingestion, and usually normalizes within 3 weeks. We obtain two connecting lines from the highest PQ level for the survivors and the lowest PQ level among the non-survivors at a given time. Patients with a PQ level between these two lines are considered treatable. The following treatment modalities are recommended to preserve kidney function: 1) extracorporeal elimination, 2) intravenous antioxidant administration, 3) diuresis with a fluid, and 4) cytotoxic drugs. In conclusion, this review provides a general overview on the diagnostic procedure and treatment modality of acute PQ intoxication, while focusing on our clinical experience.
Assuntos
Injúria Renal Aguda/diagnóstico , Herbicidas/intoxicação , Pneumopatias/diagnóstico , Paraquat/intoxicação , Injúria Renal Aguda/patologia , Injúria Renal Aguda/terapia , Antioxidantes/uso terapêutico , Creatinina/sangue , Hemoperfusão , Humanos , Quelantes de Ferro/uso terapêutico , Pneumopatias/patologia , Pneumopatias/terapia , Paraquat/sangue , Paraquat/urina , Tomografia Computadorizada por Raios XRESUMO
Glyphosate, a common herbicide, is not toxic under normal exposure circumstances. However, this chemical, when combined with a surfactant, is cytotoxic. In this study, the mechanism of the additive effect of glyphosate and TN-20, a common surfactant in glyphosate herbicides, was investigated. After exposure of rat H9c2 cells to glyphosate and TN-20 mixtures, following assays were performed: flow cytometry to determine the proportion of cells that underwent apoptosis and necrosis; western blotting to determine expression of mitochondrial proteins (Bcl-2 and Bax); immunological methods to evaluate translocation of cytochrome C; luminometric measurements to determine activity of caspases 3/7 and 9; and tetramethyl rhodamine methyl ester assay to measure mitochondrial membrane potentials. Bcl-1 intensity decreased while Bax intensity increased with exposure to increasing TN-20 and/or glyphosate concentrations. Caspase activity increased and mitochondrial membrane potential decreased only when the cells were exposed to a mixture of both TN-20 and glyphosate, but not after exposure to either one of these compounds. The results support the possibility that mixtures of glyphosate and TN-20 aggravate mitochondrial damage and induce apoptosis and necrosis. Throughout this process, TN-20 seems to disrupt the integrity of the cellular barrier to glyphosate uptake, promoting glyphosate-mediated toxicity.