RRC ID 72688
著者 Kikuchi K, Haneda M, Hayashi S, Maeda T, Nakano N, Kuroda Y, Tsubosaka M, Kamenaga T, Fujita M, Ikuta K, Anjiki K, Tachibana S, Onoi Y, Matsumoto T, Kuroda R.
タイトル P21 deficiency exhibits delayed endochondral ossification during fracture healing.
ジャーナル Bone
Abstract INTRODUCTION:Endochondral ossification is a complex biological phenomenon involving a variety of factors and cells. Cyclin-dependent kinase inhibitor 1 (p21) inhibits cell cycle progression and is affected by external stress. We recently reported that embryonic endochondral ossification is unaffected by endogenous p21 deficiency. In this study, we evaluated whether p21 expression affects endochondral ossification during fracture healing.
METHODS:Tibial fractures were introduced into p21 knockout (p21-/-) (n = 24) and wild-type C57BL/6 (p21+/+) (n = 24) mice at age 10 weeks. Fracture healing was evaluated using radiological, histological, and immunohistochemical (IHC) analyses. The effect of p21 small interfering RNA (siRNA) on ATDC5 cells was assessed in vitro.
RESULTS:The Allen score for fracture healing was lower in p21-/- mice than in p21+/+ mice. In addition, p21-/- mice exhibited larger calluses and lower bone mineral density. IHC analyses showed that p21-/- mice exhibited delayed endochondral ossification via the Ihh-Runx2-Osterix pathway in vivo. Down-regulation of p21 expression in ATDC5 cells delayed endochondral ossification in vitro.
CONCLUSIONS:p21 deficiency leads to delayed endochondral ossification by attenuating the Ihh-Runx2-Osterix pathway in vivo, and p21 deficiency in hypertrophic chondrocytes causes delayed differentiation of hypertrophic chondrocytes in vitro. p21 plays a role in endochondral ossification during fracture healing.
巻・号 165
ページ 116572
公開日 2022-12-1
DOI 10.1016/j.bone.2022.116572
PII S8756-3282(22)00249-6
PMID 36180020
MeSH Animals Cell Differentiation / physiology Chondrocytes / metabolism Core Binding Factor Alpha 1 Subunit* / genetics Core Binding Factor Alpha 1 Subunit* / metabolism Cyclin-Dependent Kinases / metabolism Fracture Healing* Mice Mice, Inbred C57BL Osteogenesis / physiology RNA, Small Interfering / metabolism
IF 4.147
リソース情報
ヒト・動物細胞 ATDC5(RCB0565)