Abstract: Objective To explore the effect of Cuscuta chinensis Lam medicated serum on the proliferation and differentiation of limb bud cells, the mRNA expressions of bone morphogenetic protein 2 (BMP-2) and CollagenⅡ, and the protein expression of CollagenⅡ. Methods Different doses of Cuscuta chinensis Lam medicated serum and normal serum were prepared by serological pharmacological method. The hindlimb buds were amputated from SD rat embryos on day 15, then were made into cell suspension. The cells were cultured by the normal serum and the high, middle and low doses of Cuscuta Chinensis Lam medicated serum in vitro for 72 h, and were divided into the negative control group and high, middle and low dose groups, respectively. Limb bud cells proliferation was evaluated by MTT. Cells differentiation was evaluated by the cartilage cell colony numbers, which were stained with alcian blue. The mRNA expressions of BMP-2 and CollagenⅡwere analyzed by RT-PCR, and protein expressioin of CollagenII was analyzed by Western blotting. Results Compared with the negative control group, the cells differentiation in low and middle dose groups were faster (P< 0.05); the cartilage cell colony numbers in middle dose group were more, while those in high dose group were less (all P < 0.05); the expressions of BMP-2 mRNA in low and middle dose groups were higher and that in high dose group was lower (all P< 0.05); the expressions of CollagenⅡmRNA and protein in high, middle and low dose groups were higher (P< 0.05). Conclusion Different doses of Cuscuta chinensis Lam medicatedserum can promote cell proliferation and increase expressions of CollagenⅡmRNA and protein. High dose of Cuscuta Chinensis Lam medicated serum can inhibit limb bud cells differentiation by decreasing BMP-2 mRNA expression.

Key words: Limd bud cell, Cuscuta Chinensis Lam, Bone morphogenetic protein 2, Medicated serum, CollagenⅡ