Background: Lead (Pb) is a heavy metal that has devastating effects on many animal tissues. In this study we investigated the effects of orally-dosed lead acetate II on osteocalcin gene (osteocalcin) expression in mesenchymal stem cells grown in an osteogenic medium. Osteocalcin is an abundant bone matrix differentiation protein.
Methods: Twelve male Wistar rats were divided into three groups of four rats each. Two groups were fed orally with 50 or 100 ppm of lead acetate II with libitum feed and water for two months. The control group was fed with libitum feed and water only. Rats were euthanized and femoral bone marrow mesenchymal stem cells (BM-MSCs) were extracted. The cells were cultured in osteogenic medium and osteocalcin expression was determined by real-time PCR.
Results: Real-time PCR showed that osteocalcin expression was significantly less in the BM-MSCs of rats that received 100 ppm of lead acetate II than in the BM-MSCs of the other groups (P<0.05), and that osteocalcin expression was less in the BM-MSCs of the group that received 50 ppm of lead acetate II than in the control group.
Conclusions: Doses of 50 and 100 ppm of lead acetate II in rats caused a significant decrease in osteocalcin expression in BM-MSCs grown in osteogenic medium.