Department of Medical Ultrasound, Taihe Hospital, Hubei University of Medicine, Shiyan, 442000, Hubei, China.
Department of Cardiology, Taihe Hospital, Hubei University of Medicine, Shiyan, 442000, Hubei, China.
BMC Cardiovasc Disord. 2020 Sep 7;20(1):403. doi: 10.1186/s12872-020-01681-0.
Dysfunction in the late Endothelial Progenitor Cells (EPCs) is responsible for endothelial repair in patients with Coronary Artery Disease (CAD), and the shear stress is beneficial for EPCs function. However, the impact of shear stress on the capacity of EPCs in CAD patients has not been elucidated yet. The C-X-C chemokine receptor 7/extracellular signal-regulated kinase (CXCR7)/(ERK) pathways are identified to regulate EPCs function in CAD patients. Here, we hypothesize that shear stress upregulates the CXCR7/ERK pathways, which restore the EPCs function in CAD patients.
The human Peripheral Blood Mononuclear Cells (PBMCs) were collected from healthy adults and CAD patients and then used for EPCs cultivation. The Lv-siRNA for human CXCR7 was transfected into induced EPCs isolated from the CAD patients. Meanwhile, the EPCs from CAD patients were subjected to shear stress generated by a biomimetic device. Next, the cell viability, migration, tube formation, and apoptosis were detected by CCK-8, Transwell assay, Matrigel, and flow cytometry, respectively. Also, the CXCR7/ERK pathways in human EPCs were analyzed by Western blotting and qRT-PCR.
Compared to the EPCs collected from normal adults, the CAD patient-derived EPCs showed reduced in vitro vasculogenic capacity. Also, the level of CXCR7 in CAD patient-derived EPCs was significantly reduced compared to the EPCs of healthy subjects. Meanwhile, the extracellular signal-regulated kinase (ERK), which represents a CXCR7 downstream signaling pathway, had decreased phosphorylation level. The shear stress treatment augmented the CXCR7 expression and also elevated ERK phosphorylation, which is comparable to the up-regulation of CAD patient-derived EPCs function. Further, the small interfering RNA (siRNA)-mediated CXCR7 knockdown diminished the enhanced migration, adhesion, and tube formation capacity of shear stress treated CAD patient-derived EPCs.
Up-regulation of the CXCR7/ERK pathways by shear stress can be a promising new target in enhancing the vasculogenic ability of CAD patient-derived EPCs.
晚期内皮祖细胞（EPCs）功能障碍是冠心病（CAD）患者内皮修复的原因，切应力有利于 EPCs 功能。然而，切应力对 CAD 患者 EPCs 能力的影响尚未阐明。C-X-C 趋化因子受体 7/细胞外信号调节激酶（CXCR7）/细胞外信号调节激酶（ERK）途径被确定为调节 CAD 患者的 EPCs 功能。在这里，我们假设切应力上调 CXCR7/ERK 途径，从而恢复 CAD 患者的 EPCs 功能。
从健康成年人和 CAD 患者中采集人外周血单核细胞（PBMCs），然后用于 EPCs 培养。将 Lv-siRNA 转染入从 CAD 患者中诱导的 EPCs。同时，用仿生装置产生的切应力处理 CAD 患者的 EPCs。然后，通过 CCK-8、Transwell 测定、Matrigel 和流式细胞术分别检测细胞活力、迁移、管形成和凋亡。此外，通过 Western blot 和 qRT-PCR 分析人 EPCs 中的 CXCR7/ERK 途径。
与正常成年人采集的 EPCs 相比，CAD 患者来源的 EPCs 显示体外血管生成能力降低。此外，与健康受试者的 EPCs 相比，CAD 患者来源的 EPCs 中 CXCR7 水平明显降低。同时，代表 CXCR7 下游信号通路的细胞外信号调节激酶（ERK）磷酸化水平降低。切应力处理增强了 CXCR7 的表达，并提高了 ERK 的磷酸化水平，这与 CAD 患者来源的 EPCs 功能的上调相当。进一步的，小干扰 RNA（siRNA）介导的 CXCR7 敲低减弱了剪切应力处理的 CAD 患者来源的 EPCs 的迁移、粘附和管形成能力的增强。
切应力对 CXCR7/ERK 途径的上调可能是增强 CAD 患者来源的 EPCs 血管生成能力的一个有前途的新靶点。
