Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, China.
Arterioscler Thromb Vasc Biol. 2024 Dec;44(12):2543-2559. doi: 10.1161/ATVBAHA.124.321399. Epub 2024 Nov 7.
In-stent restenosis is characterized by a significant reduction in lumen diameter within the stented segment, primarily attributed to excessive proliferation of vascular smooth muscle cells (VSMCs) and neointimal hyperplasia. PFN1 (profilin-1), an actin-sequestering protein extensively studied in amyotrophic lateral sclerosis, remains less explored in neointimal hyperplasia.
Utilizing single-cell RNA sequencing alongside data from in-stent restenosis patients and various experimental in-stent restenosis models (swine, rats, and mice), we investigated the role of PFN1 in promoting VSMC phenotype switching and neointimal hyperplasia.
Single-cell RNA sequencing of stenotic rat carotid arteries revealed a critical role for PFN1 in neointimal hyperplasia, a finding corroborated in stented swine coronary arteries, in-stent restenosis patients, PFN1 (SMC-specific PFN1 knockout) mice, and PFN1 overexpressed mice. PFN1 deletion was shown to suppress VSMC phenotype switching and neointimal hyperplasia in PFN1 mice subjected to a wire-injured model. To elucidate the observed discordance in PFN1 mRNA and protein levels, we identified that METTL3 (N-methyladenosine methyltransferase) and YTHDF3 (YTH N6-methyladenosine RNA binding protein F3; N-methyladenosine-specific reader) enhance PFN1 translation efficiency in an N-methyladenosine-dependent manner, confirmed through experiments involving METTL3 knockout and YTHDF3 knockout mice. Furthermore, PFN1 was mechanistically found to interact with the phosphorylation of ANXA2 (annexin A2) by recruiting Src (SRC proto-oncogene, nonreceptor tyrosine kinase), promoting the phosphorylation of STAT3 (signal transducer and activator of transcription 3), a typical transcription factor known to induce VSMC phenotype switching.
This study unveils the significance of PFN1 N-methyladenosine modification in VSMCs, demonstrating its role in promoting phenotype switching and neointimal hyperplasia through the activation of the p-ANXA2 (phospho-ANXA2)/STAT3 pathway.
支架内再狭窄的特征是支架段内管腔直径显著减小，主要归因于血管平滑肌细胞（VSMCs）的过度增殖和新生内膜过度增生。PFN1（原肌球蛋白-1）是肌萎缩侧索硬化症中广泛研究的肌动蛋白隔离蛋白，在新生内膜过度增生中研究较少。
利用单细胞 RNA 测序以及支架内再狭窄患者和各种支架内再狭窄实验模型（猪、大鼠和小鼠）的数据，我们研究了 PFN1 在促进 VSMC 表型转换和新生内膜过度增生中的作用。
对狭窄大鼠颈动脉的单细胞 RNA 测序显示，PFN1 在新生内膜过度增生中起着关键作用，这一发现在支架猪冠状动脉、支架内再狭窄患者、PFN1（血管平滑肌细胞特异性 PFN1 敲除）小鼠和 PFN1 过表达小鼠中得到了证实。PFN1 缺失可抑制 PFN1 小鼠在导线损伤模型中的 VSMC 表型转换和新生内膜过度增生。为了解释观察到的 PFN1 mRNA 和蛋白水平的不一致，我们发现 METTL3（N-甲基腺苷甲基转移酶）和 YTHDF3（YTH N6-甲基腺苷 RNA 结合蛋白 F3；N-甲基腺苷特异性阅读器）以 METTL3 敲除和 YTHDF3 敲除小鼠为实验对象，通过 N-甲基腺苷依赖性方式增强 PFN1 的翻译效率。此外，研究还发现 PFN1 与 ANXA2（膜联蛋白 A2）的磷酸化相互作用，通过招募 Src（SRC 原癌基因，非受体酪氨酸激酶）来促进 STAT3（信号转导和转录激活因子 3）的磷酸化，STAT3 是一种已知诱导 VSMC 表型转换的典型转录因子。
这项研究揭示了 PFN1 在 VSMCs 中 N-甲基腺苷修饰的重要性，证明了它通过激活 p-ANXA2（磷酸化 ANXA2）/STAT3 通路促进表型转换和新生内膜过度增生的作用。
