Hydroxyapatite Nanoparticles Facilitate Osteoblast Differentiation and Bone Formation Within Sagittal Suture During Expansion in Rats

• Main Authors: Liang W (Author), Ding P (Author), Li G (Author), Lu E (Author), Zhao Z (Author)
• Format: Book
• Published: Dove Medical Press, 2021-03-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 1177-8881
• Keywords: hydroxyapatite nanoparticles. suture-derived stem cells; osteoblast differentiation; sagittal suture; bone formation.; Therapeutics. Pharmacology; RM1-950
• Source: Drug Design, Development and Therapy, Vol Volume 15, Pp 905-917 (2021)

Wei Liang, Pengbing Ding, Guan Li, Enhang Lu, Zhenmin Zhao Department of Plastic Surgery, Peking University Third Hospital, Beijing, 100191, People&rsquo;s Republic of ChinaCorrespondence: Zhenmin ZhaoDepartment of Plastic Surgery, Peking University Third Hospital, Beijing, 100191, People&rsquo;s Republic of ChinaEmail [e-mail]: The potential of relapse of craniofacial disharmony after trans-sutural distraction osteogenesis is high due to the failure to produce a stable bone bridge in the suture gap. The aim of this study is to evaluate whether hydroxyapatite nanoparticles (nHAP) have the effect of promoting osteoblast differentiation of suture-derived stem cells (SuSCs) and bone formation in sagittal suture during expansion.Methods: SuSCs were isolated from sagittal sutures and exposed to various concentrations of nHAP (0, 25, 50, and 100 &mu;g mL&minus; 1) to determine the optimal concentration of nHAP in osteoblast differentiation via performing Western Blotting and RT-qPCR. Twenty 4-week-old male Sprague&ndash;Dawley rats were randomly assigned into 4 groups: SHAM (sham-surgery), distraction, ACS (absorbable collagen sponge) and ACS+nHAP groups. In the ACS and ACS+nHAP groups, saline solution and nHAP suspended in a saline solution were delivered by ACS placed across the sagittal suture, respectively. In the latter three groups, the suture was expanded for 14 days by 50 g of constant force via a W shape expansion device. Suture gap area, bone volume fraction (BV/TV) and bone mineral density (BMD) of sagittal sutures were assessed via micro-CT, while the mechanical properties of sagittal sutures were evaluated via nanoindentation test. The efficacy of nHAP on bone formation in sagittal suture was also evaluated via BMP-2 immunohistochemistry staining.Results: The expression of osteoblast related genes and proteins induced by 25&mu;g mL&minus; 1 nHAP were significantly higher than the other groups in vitro (p< 0.05). Furthermore, treating with 25&mu;g mL&minus; 1 nHAP in vivo, the suture gap area was significantly reduced when compared with the distraction group. Correspondingly, the BV/TV, BMD, hardness and modulus of sagittal sutures were significantly increased in the ACS+nHAP group (p< 0.05).Conclusion: The 25&mu;g mL&minus; 1 dose of nHAP delivered by ACS can facilitate bone formation into the sagittal suture during expansion via inducing osteoblast differentiation of SuSCs.Keywords: hydroxyapatite nanoparticles, suture-derived stem cells, osteoblast differentiation, sagittal suture, bone formation