Department of Orthopedics, Clinic Medical College of Anhui Medical University, the First People's Hospital of Chuzhou City, Chuzhou, Anhui, China.
Department of Orthopedics, the Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, China.
J Gene Med. 2020 Nov;22(11):e3263. doi: 10.1002/jgm.3263. Epub 2020 Sep 9.
Osteoporosis is a disease characterized by bone loss, imbalance of bone metabolism and destruction of trabecular microarchitecture. Circular RNAs (circRNAs) have been revealed as important biological regulators in human diseases. The expression characteristics and mechanism of circRNAs in osteoporosis are unclear.
The binding sites of miR-516b-5p on circ-SLC8A1 and AKAP2 mRNA were predicted using circAtlas (http://circatlas.biols.ac.cn) and miRDB (http://mirdb.org). Target sites of miR-516b-5p on circ-SLC8A1 and AKAP2 mRNA were confirmed by a dual luciferase assay. The relationship between miR-516b-5p and AKAP2 was determined by a quantitative reverse transcriptase-polymerase chain reaction. Alizarin red S staining and alkaline phosphatase staining were used to observe the level of osteogenic differentiation after transfection.
The first six circRNAs captured from the 30 circRNAs with highest expression in the bone marrow were examined in a mouse model of osteoporosis and the expression of circ-SLC8A1 was found to be significantly reduced in osteoporosis. Circ-SLC8A1 negatively regulated the expression of miR-516b-5p. Overexpression of circ-SLC8A1 blocked the inhibition of AKAP2 by miR-516b-5p.
Circ-SLC8A1 blocks the inhibitory effect of miR-516b-5p on the downstream target gene AKAP2 and promotes osteoporosis. The findings of the present might help to provide a new strategy for the treatment of osteoporosis.
骨质疏松症是一种以骨丢失、骨代谢失衡和小梁微结构破坏为特征的疾病。环状 RNA（circRNAs）已被证明是人类疾病中重要的生物调节因子。circRNAs 在骨质疏松症中的表达特征和机制尚不清楚。
使用 circAtlas（http://circatlas.biols.ac.cn）和 miRDB（http://mirdb.org）预测 miR-516b-5p 与 circ-SLC8A1 和 AKAP2 mRNA 的结合位点。通过双荧光素酶报告基因实验验证 miR-516b-5p 对 circ-SLC8A1 和 AKAP2 mRNA 的靶位。通过定量逆转录-聚合酶链反应确定 miR-516b-5p 与 AKAP2 的关系。转染后通过茜素红 S 染色和碱性磷酸酶染色观察成骨分化水平。
在骨质疏松症小鼠模型中，检测了从骨髓中表达最高的 30 个 circRNAs 中捕获的前 6 个 circRNAs，发现 circ-SLC8A1 在骨质疏松症中表达明显降低。Circ-SLC8A1 负调控 miR-516b-5p 的表达。circ-SLC8A1 的过表达阻断了 miR-516b-5p 对 AKAP2 的抑制作用。
Circ-SLC8A1 阻断了 miR-516b-5p 对下游靶基因 AKAP2 的抑制作用，促进了骨质疏松症的发生。本研究结果可能有助于为骨质疏松症的治疗提供新策略。
