FIG. 9.
The MAPK pathways are involved in ICAM-1-induced osteogenic suppression. As shown in (A), ICAM-1 overexpression induced the phosphorylation of p38/MAPK, ERK/MAPK, and JNK/SAPK. ICAM-1-induced suppression of osteogenesis was partially rescued by PD98059 (B). In contrast, the addition of SB23580HCL resulted in more serious inhibition of osteogenic differentiation (B). In addition, JNK inhibitor II did not significantly influence ICAM-1-induced osteogenic inhibition (B). Moreover, PD98059 elevated the mRNA expression of Runx2 and OCN while SB203580HCL inhibited the mRNA expression of Runx2 and OCN in ICAM-1high MSCs (C, D). JNK inhibitor II exhibited little effect on these two osteogenic markers. (*p<0.05). Scale bars represent 100 μm (B). Color images available online at www.liebertpub.com/tea