循环外泌体 circRNA_0063476 通过 miR-518c-3p/DDX6 轴损害 ISS 中骨生长标志物的表达。

Circulating Exosomal circRNA_0063476 Impairs Expression of Markers of Bone Growth Via the miR-518c-3p/DDX6 Axis in ISS.

机构信息

Departments of Orthopedics, The Second Affiliated Hospital of Nanchang University, Nanchang City, Jiangxi Province, China.

Department of Obstetrics & Gynecology, The First Affiliated Hospital of Nanchang University, Nanchang City, Jiangxi Province, China.

出版信息

Endocrinology. 2022 Oct 11;163(11). doi: 10.1210/endocr/bqac138.

DOI:10.1210/endocr/bqac138

PMID:35974445

Abstract

OBJECTIVES

Idiopathic short stature (ISS), a disorder of unknown cause, accounts for approximately 80% of the clinical diagnoses of children with short stature. Exosomal circular RNA in plasma has been implicated in various disease processes. However, the role of exosome-derived circRNA in ISS has not been elucidated yet.

METHODS

Plasma exosomes of ISS and normal children were cocultured with human chondrocytes. Microarray analysis and RT-PCR identified the differential expression of circRNA in exosomes between ISS and normal children. Hsa_circ_0063476 was upregulated or downregulated in human chondrocytes. Subsequently, overexpression rats of hsa_circ_0063476 was constructed via adenoviral vector to further validate the role of hsa_circ_0063476 on longitudinal bone growth via in vivo experiment.

RESULTS

The plasma exosome of ISS children suppressed the expression of markers of chondrocyte hypertrophy and endochondral ossification. Subsequently, upregulation of hsa_circ_0063476 in ISS exosome was identified. In vitro experiments demonstrated that chondrocyte proliferation, cell cycle and endochondral ossification were suppressed, and apoptosis was increased following hsa_circ_0063476 overexpression in human chondrocytes. Conversely, silencing hsa_circ_0063476 in human chondrocytes can show opposite outcomes. Our study further revealed hsa_circ_0063476 overexpression in vitro can enhance chondrocyte apoptosis and inhibit the expression of markers of chondrocyte proliferation and endochondral ossification via miR-518c-3p/DDX6 axis. Additionally, the rats with hsa_circ_0063476 overexpression showed a short stature phenotype.

CONCLUSIONS

The authors identified a novel pathogenesis in ISS that exosome-derived hsa_circ_0063476 retards the expression of markers of endochondral ossification and impairs longitudinal bone growth via miR-518c-3p/DDX6 axis, which may provide a unique therapeutic avenue for ISS.

摘要

目的

特发性身材矮小（ISS）是一种病因不明的疾病，约占身材矮小患儿临床诊断的 80%。血浆外泌体环状 RNA 已被证实与多种疾病过程有关。然而，外泌体来源的 circRNA 在 ISS 中的作用尚未阐明。

方法

将 ISS 和正常儿童的血浆外泌体与人类软骨细胞共培养。微阵列分析和 RT-PCR 鉴定出 ISS 和正常儿童外泌体中 circRNA 的差异表达。Hsa_circ_0063476 在人软骨细胞中上调或下调。随后，通过腺病毒载体构建 hsa_circ_0063476 的过表达大鼠，进一步通过体内实验验证 hsa_circ_0063476 对纵向骨生长的作用。

结果

ISS 儿童的血浆外泌体抑制了软骨细胞肥大和软骨内骨化的标志物表达。随后，鉴定出 ISS 外泌体中 hsa_circ_0063476 的上调。体外实验表明，hsa_circ_0063476 过表达可抑制人软骨细胞的增殖、细胞周期和软骨内骨化，促进细胞凋亡。相反，沉默人软骨细胞中的 hsa_circ_0063476 则可产生相反的结果。我们的研究进一步揭示，hsa_circ_0063476 过表达可通过 miR-518c-3p/DDX6 轴增强体外软骨细胞凋亡，抑制软骨细胞增殖和软骨内骨化标志物的表达。此外，hsa_circ_0063476 过表达的大鼠表现出身材矮小的表型。