Effects of the Pesticide Chlorpyrifos on In-Vitro Models of Trophoblast Cells

RIDANO ME; FLORES-MARTÍN J; MAGNARELLI G; GENTI-RAIMONDI S; PANZETTA-DUTARI G

San Pablo

Seminario; V Seminario en Interacción Materno- Fetal: Investigación Básica y Clínica en Biología de la Reproducción; 2010

Universidad Federal de São Paulo (UNIFESP)

Environmental contaminants may disrupt trophoblast cell function and differentiation changing the expression of specific genes. An increased risk of spontaneous abortion, low weight offspring and intrauterine growth restriction in pregnant women chronically exposed to organophosphate (OP) pesticides has been reported. At present, the underlying mechanisms involved in placental toxic effects are not fully understood. Recent studies in other cell models indicate that OP toxic effects could be mediated through alteration of transcription factors implicated in cell replication and/or differentiation. Herein, we investigated whether Chlorpyrifos (Cp), one of the most widely used OP pesticides, has any effect on genes important for placental function. As an initial approach we employed the choriocarcinoma-derived Jeg-3 cell line model. Cellular viability was tested using the MTT assay and cell morphology was analyzed by desmosome immunofluorescencent localization and nuclei staining. Expression of glial cell missing 1 (GCM1) and krüpple-like factor 6 (KLF6) transcription factors, as well as human chorionic gonadotropin b-subunit (hCGb) were determined by qRT-PCR. Jeg-3 cell viability exposed to increasing Cp concentrations (up to 100 mM) for 24 and 48 h was always greater than 75%. No major effect was observed on cell morphology, except for an increase in the cell number with fragmented and/or condensed nuclei. Cp treatment barely modified KLF6 expression, while it increased hCGb and GCMa mRNA expression. These molecules are involved in trophoblast differentiation and have been associated with hypoxia-related placental pathologies. Our results suggest that placental Cp toxicity may be due in part to its effect on trophoblast differentiation. We are extending our study to in vitro differentiating cytotrophoblasts and placental explants to confirm this hypothesis. In sum, present data support the idea that Cp modifies placenta gene expression and could have implications for understanding the adverse pregnancy outcomes associated with Cp exposure in humans.