Caffeine suppresses the expression of the Bcl-2 mRNA in BeWo cell culture and rat placenta

Chronic caffeine exposure during pregnancy has an effect on fetal growth; however, the adverse effects of caffeine on embryogenesis are not well understood and controversial. We used cDNA microarray technology to determine whether caffeine alters gene expressions in a human cytotrophoblast–like cell line, BeWo. We found that the expression of the B-cell CLL/lymphoma 2 (Bcl-2) gene in BeWo cells was down-regulated by caffeine, suggesting that chronic exposure during the gestational period could exert an influence on embryogenesis. We then focused on the Bcl-2- and Bcl-2–associated X protein gene, Bax, to study the responsive gene expression in BeWo cells as well as placentas of pregnant rats fed a diet supplemented with caffeine (2 mg/100 g body weight) during gestation, and analyzed the gene expressions using LightCycler-based quantitative real-time polymerase chain reaction assays. We found a significantly decreased level of Bcl-2 mRNA expression, which demonstrated the influence of caffeine on placental function.