Placental Biomarkers of Organophosphate Pesticides Exposure

MAGNARELLI, G.; ROVEDATTI, M.G.; SOUZA, M.S.; VERA, B.; SANTA CRUZ, S.; SABINO, G.; PECHÉN, A

Los Cocos (Córdoba)

Simposio; III Latin-American Symposium on Maternal-Fetal InteractionPlacenta – Research & Clinical; 2007

In order to evaluate enzymes as potential placental biomarkers of organophosphate pesticides (OP) effects and their associations with sensible biochemical parameters and developmental consequences, two approaches   were performed in an intensive application area. A prospective study included a cohort of 342 healthy women. Catalase (CAT), acetylcholinesterase (AChE) and glutation S-transferase were determined spectrophotometrically. Offspring and placenta morphometric information was recorded. AChE and CAT increased (40 and 41 %) in spraying period. CAT was positively correlated with newborn head circumference (HC). Placental weight and HC increased in rural newborns. To assess carboxilesterases and associated biochemical responses, a study of 18 samples included lipidic composition analysis using thin layer chromatography after subcellular fractioning. A decrease in CE1 activity (32%) was observed in spraying period. Phosphatidylcholine (PC) and phosphatidylethanolamine percentage distribution and protein content in syncitiotrophoblast mitochondria (SM) disminished (28, 23 and 48 % respectively). CE-1 activity was correlated with PC percentage and protein content. These results identify AChE, CE 1 and CAT as placental biomarkers of effect and suggest adaptative responses to OP insult. RT-PCR is being conducted to verify changes at AChE isoforms transcriptional level. Considering CE role in the pharmacokinetic behavior of most xenobiotics, CE1 inhibition would account for pharmacological adverse consequences during fetal development. Further investigations should be design for defining association between disruption of SM composition and steroidogenesis.