In Vitro Exposure of Human Luteinized Mural Granulosa Cells to Dibutyl Phthalate Affects Global Gene Expression

Exposure to dibutyl phthalate (DBP) is ubiquitous among women of reproductive age. Previous studies in animal models and in human cells in vitro have shown that exposure to DBP disrupts ovarian function. Here, we examined the effect of DBP on global gene expression in mural granulosa cells (MGCs) in vitro. Primary cultures of MGC obtained from 48 patients undergoing IVF were treated with increasing concentrations of DBP (0, 0.01, 0.1, 1, 10, or 100 µg/ml) for 48 h. Microarray analysis was used to identify genes exhibiting expression changes following DBP exposure. When compared with untreated cells, exposure to 100 µg/ml DBP resulted in significant differences in expression of 346 annotated genes (> 2-fold; q value < .05). Of them, 151 were upregulated and 195 downregulated. The main functional annotations affected by DBP were associated with cell cycle, mitosis, Rho GTPases, PLK1, Aurora B signaling pathways, and E2F-mediated regulation of DNA replication. No significant differences in gene expression were observed for the lower concentrations of DBP (0.01, 0.1, 1, and 10 µg/ml) compared with controls for both the microarray analysis and genes validated by quantitative real-time (qRT)-PCR. This study provides important molecular inputs on the effect of short-term DBP exposure on human MGCs in vitro. Our results indicate that acute treatment with high concentrations of DBP alters gene expression pathways mainly associated with the cell cycle.