Liu Yinchen, Zhou Yanbin
Department of Stomatology, The Second Xiangya Hospital of Central South University, Changsha 410011, Hunan Province, PR China.
Regen Ther. 2022 Feb 10;19:122-130. doi: 10.1016/j.reth.2022.01.003. eCollection 2022 Mar.
Periodontitis is a common chronic oral disease among the world. Periodontal ligament stem cells (PDLSCs) has been proved to be a promising tool for the treatment of periodontitis due to their capability of generating periodontal tissues. Circ_0087960 and KDM5B have been shown to participate in the process of osteogenic differentiation with unclear function and mechanism.
Circ_0087960 and KDM5B expressions were detected during the osteogenic induction of PDLSCs. The functions of circ_0087960 and KDM5B were validated by manipulating their expression with shRNA. ChIP and luciferase reporter assays were used to prove the KDM5B-based osteogenic gene regulation. Co-IP assay was used to determine the interaction between SKP2 and KDM5B. In vivo ubiquitination assay was used to test the modification of KDM5B by SKP2. RNA pull-down was used to demonstrate the interaction between circ_0087960 and KDM5B.
Circ_0087960 and KDM5B were found to be upregulated in the osteogenic differentiation of PDLSCs and promote the expression of related genes. KDM5B could directly bind and promote the expression of Runx2, ALP and OCN. KDM5B protein level in PDLSCs was controlled by SKP2-mediated protein ubiquitination and degradation. Circ_0087960 was identified to bind to KDM5B protein and protect it against SKP2-induced protein degradation, leading to the upregulation of osteogenic genes.
Circ_0087960 and KDM5B could be applied as promising therapeutic methods to stimulate the osteogenic differentiation of PDLSCs, expanding their capability in the treatment of periodontitis.
牙周炎是一种全球常见的慢性口腔疾病。牙周膜干细胞（PDLSCs）因其具有生成牙周组织的能力，已被证明是治疗牙周炎的一种有前景的工具。Circ_0087960和KDM5B已被证明参与成骨分化过程，但其功能和机制尚不清楚。
在PDLSCs成骨诱导过程中检测Circ_0087960和KDM5B的表达。通过用shRNA操纵它们的表达来验证Circ_0087960和KDM5B的功能。采用染色质免疫沉淀（ChIP）和荧光素酶报告基因检测来证明基于KDM5B的成骨基因调控。采用免疫共沉淀（Co-IP）检测来确定SKP2与KDM5B之间的相互作用。采用体内泛素化检测来测试SKP2对KDM5B的修饰。采用RNA下拉实验来证明Circ_0087960与KDM5B之间的相互作用。
发现Circ_0087960和KDM5B在PDLSCs成骨分化过程中上调，并促进相关基因的表达。KDM5B可直接结合并促进Runx2、碱性磷酸酶（ALP）和骨钙素（OCN）的表达。PDLSCs中KDM5B蛋白水平受SKP2介导的蛋白质泛素化和降解调控。Circ_0087960被鉴定为与KDM5B蛋白结合，并保护其免受SKP2诱导的蛋白质降解，从而导致成骨基因上调。
Circ_0087960和KDM5B可作为有前景的治疗方法来刺激PDLSCs的成骨分化，扩大其在牙周炎治疗中的应用能力。
