Author: Koga T, Lee SY, Niikura T, Koh A, Dogaki Y, Okumachi E, Akisue T, Kuroda R, Kurosaka M.
Affiliation: Department of Orthopedic Surgery, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. tniikura@med.kobe-u.ac.jp.
Conference/Journal: J Ultrasound Med.
Date published: 2013 Jun
Other:
Volume ID: 32 , Issue ID: 6 , Pages: 915-22 , Special Notes: doi: 10.7863/ultra.32.6.915. , Word Count: 246
Objectives- Low-intensity pulsed ultrasound (US) has been shown to have positive effects on the healing of nonunions, and bone morphogenetic protein 7 (BMP-7) is known to be a strong stimulator of osteogenic differentiation. Recently, we showed that nonunion tissue contains multilineage mesenchymal progenitor cells, suggesting that nonunion tissue-derived cells may play an important role during the healing process of nonunions. In this study, we investigated whether low-intensity pulsed US promoted BMP-7-induced osteogenic differentiation of nonunion tissue-derived cells in vitro. Methods- Nonunion tissue-derived cells were isolated from 7 patients. The cells were divided into two groups: (1) BMP-7 alone, consisting of nonunion tissue-derived cells cultured in osteogenic medium containing BMP-7 without low-intensity pulsed US treatment; and (2) BMP-7 + low-intensity pulsed US, consisting of nonunion tissue-derived cells cultured in osteogenic medium containing BMP-7 with low-intensity pulsed US treatment. The osteogenic differentiation potential and proliferation of nonunion tissue-derived cells were compared between the two groups. Results- The alkaline phosphatase activity, gene expression levels of alkaline phosphatase and runt-related transcription factor 2, and mineralization were higher in the BMP-7 + low-intensity pulsed US group than in the BMP-7-alone group. There was no significant difference in cell proliferation between the two groups. Conclusions- These findings show a significant effect of low-intensity pulsed US on the osteogenic differentiation of nonunion tissue-derived cells induced by BMP-7. This study may provide substantial evidence for the clinical combined application of BMP-7 and low-intensity pulsed US for nonunion treatment.
KEYWORDS:
bone morphogenetic protein 7, low-intensity pulsed ultrasound, nonunion, osteogenic differentiation
PMID: 23716511