Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing, Jiangsu, China.
Southeast University School of Medicine, Nanjing, Jiangsu, China.
Ren Fail. 2024 Dec;46(2):2367708. doi: 10.1080/0886022X.2024.2367708. Epub 2024 Jul 8.
Cellular senescence, macrophages infiltration, and vascular smooth muscle cells (VSMCs) osteogenic transdifferentiation participate in the pathophysiology of vascular calcification in chronic kidney disease (CKD). Senescent macrophages are involved in the regulation of inflammation in pathological diseases. In addition, senescent cells spread senescence to neighboring cells via Interferon-induced transmembrane protein3 (IFITM3). However, the role of senescent macrophages and IFITM3 in VSMCs calcification remains unexplored.
To explore the hypothesis that senescent macrophages contribute to the calcification and senescence of VSMCs via IFITM3.
Here, the macrophage senescence model was established using Lipopolysaccharides (LPS). The VSMCs were subjected to supernatants from macrophages (MCFS) or LPS-induced macrophages (LPS-MCFS) in the presence or absence of calcifying media (CM). Senescence-associated β-galactosidase (SA-β-gal), Alizarin red (AR), immunofluorescent staining, and western blot were used to identify cell senescence and calcification.
The expression of IFITM3 was significantly increased in LPS-induced macrophages and the supernatants. The VSMCs transdifferentiated into osteogenic phenotype, expressing higher osteogenic differentiation markers (RUNX2) and lower VSMCs constructive makers (SM22α) when cultured with senescent macrophages supernatants. Also, senescence markers (p16 and p21) in VSMCs were significantly increased by senescent macrophages supernatants treated. However, IFITM3 knockdown inhibited this process.
Our study showed that LPS-induced senescence of macrophages accelerated the calcification of VSMCs IFITM3. These data provide a new perspective linking VC and aging, which may provide clues for diagnosing and treating accelerated vascular aging in patients with CKD.
细胞衰老、巨噬细胞浸润和血管平滑肌细胞（VSMCs）成骨转分化参与慢性肾脏病（CKD）血管钙化的病理生理学。衰老的巨噬细胞参与调节病理性疾病的炎症。此外，衰老细胞通过干扰素诱导跨膜蛋白 3（IFITM3）将衰老传递给邻近细胞。然而，衰老巨噬细胞和 IFITM3 在 VSMCs 钙化中的作用仍未被探索。
探讨衰老的巨噬细胞是否通过 IFITM3 促进 VSMCs 钙化和衰老的假说。
本研究使用脂多糖（LPS）建立了巨噬细胞衰老模型。在存在或不存在钙化培养基（CM）的情况下，将 VSMCs 置于巨噬细胞上清液（MCFS）或 LPS 诱导的巨噬细胞（LPS-MCFS）中。通过衰老相关β-半乳糖苷酶（SA-β-gal）、茜素红（AR）免疫荧光染色和 Western blot 鉴定细胞衰老和钙化。
LPS 诱导的巨噬细胞及其上清液中 IFITM3 的表达显著增加。当用衰老的巨噬细胞上清液培养时，VSMCs 向成骨表型分化，表达更高的成骨分化标志物（RUNX2）和更低的 VSMCs 结构标志物（SM22α）。此外，衰老标志物（p16 和 p21）在 VSMCs 中的表达也显著增加。然而，IFITM3 敲低抑制了这一过程。
本研究表明，LPS 诱导的巨噬细胞衰老加速了 VSMCs 的钙化，IFITM3 在此过程中起关键作用。这些数据为 VC 和衰老之间提供了新的联系，这可能为诊断和治疗 CKD 患者加速血管老化提供线索。
