Plasma membrane lipid composition and domain organization affects organophosphate pesticides action on secondary targets

MARDIROSIAN M.; TRICERRI MA; VENTURINO A; JAUREGUIBERRY MS

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencia; 2017

SAA, SAB, SAIB, SAIC, SAI, SAFE, SAH, SAP, SAB, SAFIS

Although acetilcholinesterase (AChE) is the primary target of organophosphate pesticides (OP), secondary targets such as oxidative stress enzymes become relevant at sublethal concentrations. Plasma membrane (PM) changes in cholesterol (Chol) content or fatty acid (FA) insaturation may alter its domains and affect cell functions. OP have been suggested to compete with Chol for partition domains at the PM and cause structure perturbations. Our objective was to analyze the effects of the OP chlorpyrifos (CPP) on oxidative stress enzymes catalase, glutathione S-transferase and glutathione reductase in transfected CHO-K1 cells, which do not express AChE, differing in lipid composition and PM fluidity. One cell line (SCD) shows higher monounsaturated FA content but keeps fluidity by increasing Chol content, while other (FADS) has higher polyunsaturated FA and lower Chol content with increased PM fluidity. The different cell lines were exposed during 24h to 0.5 and 250 μM CPP and the enzymes were measured kinetically by spectrophotometry. Data were analyzed by ANOVA and Tuckey post hoc test. Glutathione S-transferase and reductase activities decreased significantly in control cells exposed to CPP (50 and 40% respectively) (p