Fig. 6

p38 MAPK signaling is involved in MSCs osteogenic differentiation. MSCs were transfected with siRNA-p38 and examined for a the protein expression of p-p38, p38, p-ERK1/2, ERK1/2, p-JNK, and JNK by immunoblotting, β-actin was used as the internal control. b Densitometry of relative protein levels of p-p38, p38, p-ERK1/2, ERK1/2, p-JNK, and JNK, (n = 3), *p < 0.05. c The protein expression of OPN, BSP, Runx2, and Col I by immunoblotting. d Densitometry of relative protein levels of OPN, BSP, Runx2, and Col I, (n = 3), *p < 0.05. e Osteogenic differentiation was determined by ALP staining. f Relative ALP activity (n = 3), *p < 0.05. g Calcium nodules formation by Alizarin Red staining. h Relative mineralization levels (n = 3), *p < 0.05