Spine Research Center of Wannan Medical College, Key Laboratory of Non-coding RNA Transformation Research of Anhui Higher Education Institution, Department of Spine Surgery, Yijishan hospital of Wannan Medical College, Wuhu, Anhui 241001, China.
Curr Mol Pharmacol. 2020;13(4):328-341. doi: 10.2174/1874467213666200204143740.
Osteoarthritis is a disorder of joints featuring inflammation and degeneration of articular cartilage. Recently, miRs have been found to be associated in the regulation of chondrocytes and their apoptosis. miR-18a-3p has been found to be associated in the pathogenesis of rheumatoid arthritis, however, its role in articular cartilage tissues remains unclear.
C57BL/6 strain of mice and human cartilage tissue were used for the study. Histological analysis was done on isolated cartilage samples followed by TUNEL assay and immunohistochemical analysis. The chondrocytes were isolated from mouse and human cartilage tissues, RNA was isolated and subjected for qRT-PCR analysis. The chondrocytes were transfected with miR-18a-3p agomir, antagomir and siHOXA-1. Luciferase assay was done in 293T cells. Flow cytometry analysis was done and western blot analysis for studying the expression of proteins.
The expression of miR-18a-3p was upregulated in chondrocytes after exposing them to interlukin- 1β (IL-1β) in vitro. The transfection of miR-18a-3p antagomir halted the IL-1β mediated apoptosis. The luciferase assay suggested that miR-18a-3p targets the 3'UTR region of HOXA1 gene thus blocking its expression. The treatment of HOXA1 siRNA demonstrated the rescuing effect of miR- 18a-3p antagomir on the apoptosis of chondrocytes. Treatment of miR-18a-3p antagomir attenuated the surface of cartilage in osteoarthritis mice and the agomir worsened it. TUNEL assay suggested decreased apoptosis and over-expression of HOAX1 in osteoarthritis mice post miR-18a-3p knockdown.
The findings confirmed the involvement of miR-18a-3p/HOXA1 pathway as a potential mechanism in the regulation of Osteoarthritis.
骨关节炎是一种关节疾病，其特征为关节软骨炎症和退变。最近发现，miRs 参与了软骨细胞及其凋亡的调节。miR-18a-3p 已被发现与类风湿关节炎的发病机制有关，但其在关节软骨组织中的作用尚不清楚。
本研究使用 C57BL/6 品系小鼠和人软骨组织。对分离的软骨样本进行组织学分析，然后进行 TUNEL 检测和免疫组织化学分析。从小鼠和人软骨组织中分离软骨细胞，提取 RNA 并进行 qRT-PCR 分析。用 miR-18a-3p agomir、antagomir 和 siHOXA-1 转染软骨细胞。在 293T 细胞中进行荧光素酶测定。进行流式细胞术分析和 Western blot 分析以研究蛋白质的表达。
体外培养软骨细胞时，白细胞介素 1β（IL-1β）可使 miR-18a-3p 的表达上调。miR-18a-3p antagomir 的转染可阻止 IL-1β介导的凋亡。荧光素酶测定表明，miR-18a-3p 靶向 HOXA1 基因的 3'UTR 区域，从而阻断其表达。HOXA1 siRNA 的处理证明了 miR-18a-3p antagomir 对软骨细胞凋亡的挽救作用。miR-18a-3p antagomir 的处理可减轻骨关节炎小鼠软骨表面的损伤，而 agomir 则加重了这种损伤。TUNEL 检测表明，miR-18a-3p 敲低后骨关节炎小鼠的凋亡减少，HOAX1 过表达。
研究结果证实了 miR-18a-3p/HOXA1 通路作为调节骨关节炎的潜在机制的参与。
