A Molecular Basis for Enhanced Biocompatibility of Osteoblasts on Poly(lactic-co-glycolic Acid)-multi-wall Carbon Nanotubes Nanocomposite
- 材料学院－已发表论文 
The physical properties and performance of polymer matrix composites can be significantly improved by the addition of carbon nanotubes (CNTs) as reinforcements. Nanocomposites formed from poly(lactic-co-glycolic acid) (PLGA) and carboxylated multi-wall CNTs (MWCNTs) have been recently fabricated in order to generate suitable implant materials for bone tissue engineering. Here, we reported the cellular reactions of osteoblasts grown on PLGA-MWCNTs nanocomposite films, and investigated the molecular mechanisms responsible for the artificial surface of the films-induced modulation of cellular functions. The results showed that interaction with the PLGA-MWCNTs films induced an increased cell proliferation, DNA synthesis and S phase accumulation, and modulated osteogenic differentiation in osteoblasts. The well-defined stress fibers and enhanced phosphorylation of focal adhesion kinase (FAK) were also observed in osteoblasts cultured on PLGA-MWCNTs films. Assessment of signaling molecules suggested that extracellular-signal-regulated kinases (ERK1/2), but not p38 mitogen-activated protein kinases (p38MAPK) or c-Jun-N-terminal kinases (JNK), were selectively phosphorylated in osteoblasts grown on PLGA-MWCNTs film. Pre-treatment of osteoblasts with PD98059, a specific inhibitor of ERK 1/2, resulted in a significant reduction in cell viability and stress fibers formation of osteoblasts cultured on PLGA-MWCNTs film, suggesting the involvement of ERK1/2 in cell viability and stress fibers formation. These results provided the molecular basis for enhanced biocompatibility of osteoblasts response to the surfaces of PLGA-MWCNTs nanocompostie films, which may account for the potential use of PLGA-MWCNTs composites as promising substrates for bone regenerative applications.