Department of Cardiovascular Surgery, Changhai Hospital, Naval Medical University, 168 Changhai Road, Shanghai, 200433, China.
Department of Cardiology, Changhai Hospital, Naval Medical University, Shanghai, 200433, China.
Cell Mol Life Sci. 2022 Feb 21;79(3):146. doi: 10.1007/s00018-022-04177-6.
Calcific aortic valve disease (CAVD) is a common valve disease characterized by the fibro-calcific remodeling of the aortic valves, which is an actively regulated process involving osteogenic differentiation of valvular interstitial cells (VICs). MicroRNA (miRNA) is an essential regulator in diverse biological processes in cells. The present study aimed to explore the role and mechanism of miR-22 in the osteogenic differentiation of VICs. The expression profile of osteogenesis-related miRNAs was first detected in aortic valve tissue from CAVD patients (n = 33) and healthy controls (n = 12). miR-22 was highly expressed in calcified valve tissues (P < 0.01), and the expression was positively correlated with the expression of OPN (r = 0.820, P < 0.01) and Runx2 (r = 0.563, P < 0.01) in VICs isolated from mild or moderately calcified valves. The sustained high expression of miR-22 was also validated in an in-vitro VICs osteogenic model. Adenovirus-mediated gain-of-function and loss-of-function experiments were then performed. Overexpression of miR-22 significantly accelerated the calcification process of VICs, manifested by significant increases in calcium deposition, alkaline phosphate activity, and expression of osteoblastic differentiation markers. Conversely, inhibition of miR-22 significantly negated the calcification process. Subsequently, calcium-binding protein 39 (CAB39) was identified as a target of miR-22. Overexpression of miR-22 significantly reduced the expression of CAB39 in VICs, leading to decreased catalytic activity of the CAB39-LKB1-STRAD complex, which, in turn, exacerbated changes in the AMPK-mTOR signaling pathway, and ultimately accelerated the calcification process. In addition, ROS generation and autophagic activity during VIC calcification were also regulated by miR-22/CAB39 pathway. These results indicate that miR-22 is an important accelerator of the osteogenic differentiation of VICs, and a potential therapeutic target in CAVD.
钙化性主动脉瓣疾病（CAVD）是一种常见的瓣膜疾病，其特征为主动脉瓣的纤维-钙化重塑，这是一个涉及瓣膜间质细胞（VIC）成骨分化的主动调节过程。微小 RNA（miRNA）是细胞中多种生物学过程的重要调节因子。本研究旨在探讨 miR-22 在 VIC 成骨分化中的作用和机制。首先检测了 33 例 CAVD 患者和 12 例健康对照者主动脉瓣组织中成骨相关 miRNA 的表达谱。miR-22 在钙化瓣膜组织中高表达（P<0.01），且与分离自轻度或中度钙化瓣膜的 VIC 中 OPN（r=0.820，P<0.01）和 Runx2（r=0.563，P<0.01）的表达呈正相关。在体外 VIC 成骨模型中也验证了 miR-22 的持续高表达。然后进行了腺病毒介导的功能获得和功能丧失实验。miR-22 的过表达显著加速了 VIC 的钙化过程，表现为钙沉积、碱性磷酸酶活性和骨细胞分化标志物表达的显著增加。相反，抑制 miR-22 显著否定了钙化过程。随后，鉴定出钙结合蛋白 39（CAB39）是 miR-22 的靶标。miR-22 的过表达显著降低了 VIC 中的 CAB39 表达，导致 CAB39-LKB1-STRAD 复合物的催化活性降低，进而加剧了 AMPK-mTOR 信号通路的变化，最终加速了钙化过程。此外，miR-22/CAB39 通路还调节 VIC 钙化过程中的 ROS 生成和自噬活性。这些结果表明，miR-22 是 VIC 成骨分化的重要促进剂，也是 CAVD 的潜在治疗靶点。
