Effects of vibration on the proteome expression of anterior cruciate ligament cells

Recent reports have suggested that vibration has beneficial effects on knee healing response; however, the biomechanism of these beneficial effects still need to be determined on the anterior cruciate ligament (ACL) cell level. In this study, we applied a 20 Hz vibration to ACL cells, which produced a 20% increase (P < 0.001) in cell activity and 17% increase (P < 0.001) in intracellular sulfated glycosaminoglycan levels. In the 20 Hz vibration-stimulated ACL cell group, eight up-regulated (100 ∼ 300%) protein spots were identified compared with the control group by proteomics analysis. Among these proteins, Annexin A2 and Prolyl 4 hydroxylase (PH4B) were shown to have a 71% and 16% higher expression, respectively, in the 20 Hz vibration-stimulated ACL cell group by Western blotting (P < 0.001). These results indicate that vibration produces a positive cellular environment, and Annexin A2 and prolyl 4 hydroxylase are expected to help ligament repair and ACL cell proliferation by controlling cell membrane and extracellular matrix formation.