Phosphorylated pullulan promotes calcification during bone regeneration in the bone defects of rat tibiae

Frontiers in Bioengineering and Biotechnology

Bioengineering and Biotechnology

Yasuhiro Yoshida¹  Ko Nakanishi¹  Hiromi Hongo²  Haruhi Maruoka²  Norio Amizuka²  Tomoka Hasegawa²  Mai Haraguchi-Kitakamae³  Tomomaya Yamamoto⁴  Hotaka Ishizu⁵  Yasuhito Morimoto⁶  Kumiko Yoshihara⁷  Tsuneyuki Yamamoto⁸  Tomohiro Shimizu⁹  Tsutomu Sugaya^1,10 

[1]Biomaterials and Bioengineering, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[2]Developmental Biology of Hard Tissue, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[3]Developmental Biology of Hard Tissue, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[4]Division of Craniofacial Development and Tissue Biology, Tohoku University Graduate School of Dentistry, Sendai, Japan

[5]Developmental Biology of Hard Tissue, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[6]Northern Army Medical Unit, Camp Makomanai, Japan Ground Self-Defense Forces, Sapporo, Japan

[7]Developmental Biology of Hard Tissue, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[8]Orthopedics, Faculty of Medicine, Hokkaido University, Sapporo, Japan

[9]Developmental Biology of Hard Tissue, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[10]Periodontology and Endodontology, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[11]National Institute of Advanced Industrial Science and Technology (AIST), Health and Medical Research Institute, Takamatsu, Japan

[12]Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan

[13]Oral Functional Anatomy, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

[14]Orthopedics, Faculty of Medicine, Hokkaido University, Sapporo, Japan

[15]Periodontology and Endodontology, Faculty of Dental Medicine, Hokkaido University, Sapporo, Japan

关键词: phosphorylated pullulan;    β-tricalcium phosphate;    bone regeneration;    calcification;    transmission electron microscopy (TEM);   

DOI  :  10.3389/fbioe.2023.1243951

 received in 2023-06-22, accepted in 2023-09-27,  发布年份 2023

来源: Frontiers

【 摘 要 】

The current study aimed to evaluate bone tissue regeneration using a combination of β-tricalcium phosphate (βTCP) and phosphorylated pullulan (PPL, a phosphate-rich polysaccharide polymer consisting of maltotriose units). Round defects of 2 mm diameter were created in the arterial center of rat tibiae, which were further treated with vehicle (control group), βTCP (βTCP group), or βTCP + PPL (βTCP + PPL group) grafts. The control specimens without bone grafts exhibited rapid bone formation after 1 week; however, the regenerated bone was not resorbed until 4 weeks. In contrast, βTCP-grafted specimens exhibited fewer but thicker trabeculae, whereas the βTCP + PPL group displayed many fine trabeculae at 4 weeks. In the βTCP + PPL group, new bone was associated with the βTCP granules and PPL. Similarly, PHOSPHO1-positive osteoblasts were localized on the βTCP granules as well as the PPL. On the other hand, TRAP-reactive osteoclasts predominantly localized on newly-formed bone and βTCP granules rather than on the PPL. No significant differences were observed in the expression of Alp, Integrin αv, Osteopontin, Osteocalcin, and Dmp-1 in PPL-treated MC3T3-E1 osteoblastic cells, suggesting that PPL did not facilitate osteoblastic differentiation. However, von Kossa staining identified abundant needle-like calcified structures extending inside the PPL. Furthermore, transmission electron microscopy (TEM) revealed many globular structures identical to calcified nodules. In addition, calcified collagen fibrils were observed in the superficial layer of the PPL. Thus, PPL may serve as a scaffold for osteoblastic bone formation and promotes calcification on its surface. In conclusion, we speculated that βTCP and PPL might promote bone regeneration and could be integrated into promising osteoconductive materials.

【 授权许可】

Unknown   
Copyright © 2023 Morimoto, Hasegawa, Hongo, Yamamoto, Maruoka, Haraguchi-Kitakamae, Nakanishi, Yamamoto, Ishizu, Shimizu, Yoshihara, Yoshida, Sugaya and Amizuka.