Antioxidant enzyme activities, molecular docking studies, MM-GBSA, and molecular dynamic of chlorpyrifos in freshwater fish Capoeta umbla.

Chlorpyrifos (CPF), which was started to be used in 1965, is a broad spectrum organophosphate insecticide that is used more and more day by day. Commonly used to control pests in farmland and homes, CPF is more toxic to fish than organochlorine compounds. CPF poses a serious threat to the health of humans and aquatic organisms. This paper studies the relationship between CPF exposure and antioxidant enzyme activities in gill, kidney and liver tissues of Capoeta umbla. Different time intervals (12, 24, 48, 72, and 96 h) and CPF doses (55 and 110 µg L-1) were used in the study. Spectrophotometrical measures were taken in all tissues for antioxidant enzyme activities and malondialdehyde (MDA) levels, as indices of the lipid peroxidation (LPO). A positive relationship between CPF and MDA levels was found in the study at a statistically significant level (p < 0.05). The study also found a negative relationship between CPF levels and catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR) activity. Independent variables in the study can act as biomarkers of CPF exposure. The study recommends employing proper ecotoxicological risk evaluations in cases of CPF usage as a pesticide. The activities of the studied molecules against various proteins that are crystal structure of human peroxiredoxin 5 (PDB ID: 1HD2) has docking score value is -2.67, crystal structure of Bovine Xanthine Oxidase (PDB ID: 3NRZ) has docking score value is -3.76, and crystal structure of antibacterial FabH (PDB ID: 4Z8D) has docking score value is -3.16, were compared. Molecular dynamic (MD) calculations were made in 100 ns. MM/GBSA methods are calculated binding free energy. Afterwards, ADME/T analysis was performed to examine the some properties of the molecules.Communicated by Ramaswamy H. Sarma.

Apoptotic effects and glucose-6-phosphate dehydrogenase responses in liver and gill tissues of rainbow trout treated with chlorpyrifos.

We investigated apoptotic effects and changes in glucose-6-phosphate dehydrogenase (G6PD) enzyme activity in liver and gill tissues of fish exposed to chlorpyrifos. Three different chlorpyrifos doses (2.25, 4.5 and 6.75 µg/L) were administrated to rainbow trout at different time intervals (24, 48, 72 and 96 h). Acute exposure to chlorpyrifos showed time dependent decrease in G6PD enzyme activity at all concentrations (p < 0.05). Immunohistochemical results showed that chlorpyrifos caused mucous cell loss in gill tissue and apoptosis via caspase-3 activation in fish. The present study suggested that chlorpyrifos inhibits G6PD enzyme and causes mucous cell loss in gill and apoptosis in gill and liver tissues.