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. 2019 Aug 31;20(1):396.
doi: 10.1186/s12891-019-2777-8.

Silicate-substituted strontium apatite nano coating improves osteogenesis around artificial ligament

Takuya Egawa  1 , Yusuke Inagaki  2 , Manabu Akahane  3 , Akira Furukawa  4 , Kazuya Inoue  4 , Munehiro Ogawa  4 , Yasuhito Tanaka  4
Affiliations

Silicate-substituted strontium apatite nano coating improves osteogenesis around artificial ligament

Takuya Egawa et al. BMC Musculoskelet Disord. .

Abstract

Background: Treatment of anterior cruciate ligament injuries commonly involves the use of polyethylene terephthalate (PET) artificial ligaments for reconstruction. However, the currently available methods require long fixation periods, thereby necessitating the development of alternative methods to accelerate the healing process between tendons and bones. Thus, we developed and evaluated a novel technique that utilizes silicate-substituted strontium (SrSiP).

Methods: PET films, nano-coated with SrSiP, were prepared. Bone marrow mesenchymal cells (BMSCs) from femurs of male rats were cultured and seeded at a density of 1.0 × 104/cm2 onto the SrSiP-coated and non-coated PET film, and subsequently placed in an osteogenic medium. The osteocalcin concentration secreted into the medium was compared in each case. Next, PET artificial ligament, nano-coated with SrSiP, were prepared. BMSCs were seeded at a density of 4.5 × 105/cm2 onto the SrSiP-coated, and non-coated artificial ligament, and then placed in osteogenic medium. The osteocalcin and calcium concentrations in the culture medium were measured on the 8th, 10th, 12th, and 14th day of culture. Furthermore, mRNA expression of osteocalcin, alkaline phosphatase (ALP), bone morphogenetic protein-2 (BMP2), and runt-related transcription factor 2 (Runx2) was evaluated by qPCR. We transplanted the SrSiP-coated and non-coated artificial ligament to the tibiae of mature New Zealand white rabbits. Two months later, we sacrificed them and histologically evaluated them.

Results: The secretory osteocalcin concentration in the medium on the film was significantly higher for the SrSiP group than for the non-coated group. Secretory osteocalcin concentration in the medium on the artificial ligament was also significantly higher in the SrSiP group than in the non-coated group on the 14th day. Calcium concentration on the artificial ligament was significantly lower in the SrSiP group than in the non-coated group on the 8th, 10th, 12th, and 14th day. In qPCR as well, OC, ALP, BMP2, and Runx2 mRNA expression were significantly higher in the SrSiP group than in the non-coated group. Newly formed bone was histologically found around the artificial ligament in the SrSiP group.

Conclusions: Our findings demonstrate that artificial ligaments using SrSiP display high osteogenic potential and thus may be efficiently used in future clinical applications.

Keywords: Anterior cruciate ligament injuries; Nano coating; Osteogenesis; PET artificial ligament; Silicate-substituted strontium.

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Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Osteocalcin concentration in nano-coated PET film culture medium. The concentration in SrSiP was significantly higher than in the non-coated sample. Data are shown as the mean ± standard deviation (SD). Asterisk indicates p < 0.05
Fig. 2
Fig. 2
SEM image and EDS results. a Before cell culture. b After cell culture
Fig. 3
Fig. 3
Osteocalcin concentration in nano-coated PET fiber artificial ligament culture medium. Osteocalcin concentration on the 8th, 10th, 12th, and 14th day was recorded. Osteocalcin concentration in SrSiP was significantly higher than in the non-coated sample on the 14th day in the culture supernatant. The solid and broken lines indicate the data obtained in SrSiP and non-coated samples. Data are shown as the mean ± SD. Asterisk indicates p < 0.05 vs. non-coated group (control)
Fig. 4
Fig. 4
Calcium concentration in nano-coated PET fiber artificial ligament culture medium. Calcium concentration on the 8th, 10th, 12th, and 14th day was recorded. Calcium concentration in SrSiP was significantly lower than in the non-coated sample on the 8th, 10th, 12th, and 14th day of the culture supernatant. The solid and broken lines indicate the data obtained in SrSiP and non-coated samples. Data are shown as the mean ± SD. Asterisk indicates p < 0.05 vs. non-coated group (control)
Fig. 5
Fig. 5
mRNA expression in nano-coated PET fiber artificial ligament. a Osteocalcin; b ALP; c BMP2; d Runx2. For Osteocalcin, ALP, BMP2, and Runx2, mRNA expressions in SrSiP were all significantly higher than in the non-coated group. Data are shown as the mean ± SD. Asterisk indicates p < 0.05
Fig. 6
Fig. 6
Histological findings. Hematoxylin and eosin stained sections showed newly formed bone around the artificial ligaments of the SrSiP group. The asterisks indicate PET artificial ligament fibers. The black arrows indicate the newly formed bone area. The white arrows indicate osteocytes. The white arrowheads indicate osteoblasts
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References

    1. Yasuda K, Kondo E, Ichiyama H, Kitamura N, Tanabe Y, Tohyama H, Minami A. Anatomic reconstruction of the anteromedial and posterolateral bundles of the anterior cruciate ligament using hamstring tendon grafts. Arthroscopy. 2004;20:1015–1025. doi: 10.1016/j.arthro.2004.08.010. - DOI - PubMed
    1. Inagaki Y, Kondo E, Kitamura N, Onodera J, Yagi T, Tanaka Y, Yasuda K. Prospective clinical comparisons of semitendinosus versus semitendinosus and gracilis tendon autografts for anatomic double-bundle anterior cruciate ligament reconstruction. J Orthop Sci. 2013;18:754–761. doi: 10.1007/s00776-012-0333-6. - DOI - PubMed
    1. Chen CH, Chen WJ, Shih CH, Yang CY, Liu SJ, Lin PY. Enveloping the tendon graft with periosteum to enhance tendon-bone healing in a bone tunnel: a biomechanical and histologic study in rabbits. Arthroscopy. 2003;19:290–296. doi: 10.1053/jars.2003.50014. - DOI - PubMed
    1. Mutsuzaki H, Sakane M, Nakajima H, Ito A, Hattori S, Miyanaga Y, Ochiai N, Tanaka J. Calcium-phosphate-hybridized tendon directly promotes regeneration of tendon-bone insertion. J Biomed Mater Res. 2004;70:319–327. doi: 10.1002/jbm.a.30084. - DOI - PubMed
    1. Yeh WL, Lin SS, Yuan LJ, Lee KF, Lee MY, Ueng SWN. Effects of hyperbaric oxygen treatment on tendon graft and tendon-bone integration in bone tunnel: biochemical and histological analysis in rabbits. J Orthop Res. 2007;25:636–645. doi: 10.1002/jor.20360. - DOI - PubMed

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