靶向抑制 PTPN22 可减轻小鼠主动脉瓣间质细胞成骨反应和主动脉瓣病变。

BACKGROUND: Calcific aortic valve disease (CAVD) is the most prevalent valvular disease and has high morbidity and mortality. CAVD is characterized by complex pathophysiological processes, including inflammation-induced osteoblastic differentiation in aortic valve interstitial cells (AVICs). Novel anti-CAVD agents are urgently needed. Protein tyrosine phosphatase nonreceptor type 22 (PTPN22), an intracellular nonreceptor-like protein tyrosine phosphatase, is involved in several chronic inflammatory diseases, including rheumatoid arthritis and diabetes. However, it is unclear whether PTPN22 is involved in the pathogenesis of CAVD. METHODS: We obtained the aortic valve tissue from human and cultured AVICs from aortic valve. We established CAVD mice model by wire injury. Transcriptome sequencing, western bolt, qPCR, and immunofluorescence were performed to elucidate the molecular mechanisms. RESULTS: Here, we determined that PTPN22 expression was upregulated in calcific aortic valve tissue, AVICs treated with osteogenic medium, and a mouse model of CAVD. In vitro, overexpression of PTPN22 induced osteogenic responses, whereas siRNA-mediated PTPN22 knockdown abolished osteogenic responses and mitochondrial stress in the presence of osteogenic medium. In vivo, PTPN22 ablation ameliorated aortic valve lesions in a wire injury-induced CAVD mouse model, validating the pathogenic role of PTPN22 in CAVD. Additionally, we discovered a novel compound, 13-hydroxypiericidin A 10-O-α-D-glucose (1 → 6)-β-D-glucoside (S18), in a marine-derived Streptomyces strain that bound to PTPN22 with high affinity and acted as a novel inhibitor. Incubation with S18 suppressed osteogenic responses and mitochondrial stress in human AVICs induced by osteogenic medium. In mice with aortic valve injury, S18 administration markedly alleviated aortic valve lesions. CONCLUSION: PTPN22 plays an essential role in the progression of CAVD, and inhibition of PTPN22 with S18 is a novel option for the further development of potent anti-CAVD drugs. Therapeutic inhibition of PTPN22 retards aortic valve calcification through modulating mitochondrial dysfunction in AVICs.

背景：钙化性主动脉瓣疾病（CAVD）是最常见的瓣膜病，具有高发病率和死亡率。CAVD 的特征是复杂的病理生理过程，包括主动脉瓣间质细胞（AVICs）中的炎症诱导成骨细胞分化。迫切需要新型抗 CAVD 药物。蛋白酪氨酸磷酸酶非受体型 22（PTPN22）是一种细胞内非受体样蛋白酪氨酸磷酸酶，参与包括类风湿关节炎和糖尿病在内的多种慢性炎症性疾病。然而，PTPN22 是否参与 CAVD 的发病机制尚不清楚。

方法：我们从人主动脉瓣组织中获取组织并培养主动脉瓣间质细胞（AVICs），通过钢丝损伤建立 CAVD 小鼠模型。进行转录组测序、western bolt、qPCR 和免疫荧光实验以阐明分子机制。

结果：我们确定 PTPN22 在钙化主动脉瓣组织、成骨培养基处理的 AVICs 和 CAVD 小鼠模型中表达上调。体外，过表达 PTPN22 诱导成骨反应，而 siRNA 介导的 PTPN22 敲低则在成骨培养基存在的情况下消除了成骨反应和线粒体应激。体内，PTPN22 缺失可改善钢丝损伤诱导的 CAVD 小鼠模型中的主动脉瓣病变，验证了 PTPN22 在 CAVD 中的致病作用。此外，我们在一株海洋来源的链霉菌中发现了一种新型化合物 13-羟基胡椒啶 A 10-O-α-D-吡喃葡萄糖（1→6）-β-D-吡喃葡萄糖苷（S18），该化合物与 PTPN22 具有高亲和力，并作为一种新型抑制剂发挥作用。S18 孵育可抑制成骨培养基诱导的人 AVICs 的成骨反应和线粒体应激。在主动脉瓣损伤的小鼠中，S18 给药可显著减轻主动脉瓣病变。

结论：PTPN22 在 CAVD 的进展中起重要作用，用 S18 抑制 PTPN22 是进一步开发有效的抗 CAVD 药物的新选择。通过调节 AVICs 中的线粒体功能障碍，抑制 PTPN22 可延缓主动脉瓣钙化。