Department of Geriatric Cardiology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, People's Republic of China.
Mol Cell Biochem. 2011 Sep;355(1-2):99-108. doi: 10.1007/s11010-011-0843-0. Epub 2011 May 21.
We have recently demonstrated that endothelial progenitor cells (EPCs) inhibit AngII-induced proliferation of vascular smooth muscle cells (VSMCs) by inactivating MAPKs and NF-κB signaling pathway and reducing expression of oncogene c-myc and c-fos. The inhibitory effect of EPCs on VSMCs is associated with paracrine mechanism. However, the potential mechanism of EPCs on the regulation of AngII-induced proliferation of VSMCs was unknown. Calcitonin gene-related peptide (CGRP) could inhibit AngII-induced proliferation and transformation of VSMCs. However, it has not been known whether CGRP released from EPCs is a potential regulator in regulation of AngII-induced proliferation of VSMCs. Early endothelial progenitor cell-conditioned medium(E-EPC-CM) was pre-incubated with functional blocking antibodies against CGRP for 1 h or VSMCs was preteated with CGRP(837)(CGRP receptor antagonist) for 1 h before VSMCs were pretreated with CM for 30 min. DNA synthesis ability, total protein levels, cell survival, signal transduction, and expressions of c-myc and c-fos of VSMCs induced by AngII (10(-6)mol/l) were detected to assess the role of CGRP in AngII-induced proliferation of VSMCs. E-EPC-CM could significantly inhibit AngII-induced DNA synthesis ability, total protein levels, cell survival, phosphorylation of ERK, JNK, p38, p65, and expressions of c-myc and c-fos compared with the control group(P < 0.05). However, Pretreatment with anti-CGRP antibody and CGRP(837) could significantly weaken the inhibitory effect of E-EPC-CM on proliferation of VSMCs induced by AngII (P < 0.05). EPCs exert anti-proliferative effects on VSMCs mediated by the release of CGRP.
我们最近的研究表明，内皮祖细胞（EPCs）通过抑制 MAPKs 和 NF-κB 信号通路以及降低癌基因 c-myc 和 c-fos 的表达来抑制血管平滑肌细胞（VSMCs）增殖。EPCs 对 VSMCs 的抑制作用与旁分泌机制有关。然而，EPCs 对 AngII 诱导的 VSMCs 增殖的调节的潜在机制尚不清楚。降钙素基因相关肽（CGRP）可抑制 AngII 诱导的 VSMCs 增殖和转化。然而，尚不清楚来自 EPCs 的 CGRP 是否是调节 AngII 诱导的 VSMCs 增殖的潜在调节剂。将早期内皮祖细胞条件培养基（E-EPC-CM）与针对 CGRP 的功能阻断抗体预孵育 1 小时，或用 CGRP（837）（CGRP 受体拮抗剂）预处理 VSMCs 1 小时，然后再用 CM 预处理 VSMCs 30 分钟。检测 AngII（10（-6）mol/L）诱导的 VSMCs 的 DNA 合成能力、总蛋白水平、细胞存活、信号转导以及 c-myc 和 c-fos 的表达，以评估 CGRP 在 AngII 诱导的 VSMCs 增殖中的作用。与对照组相比，E-EPC-CM 可显著抑制 AngII 诱导的 DNA 合成能力、总蛋白水平、细胞存活、ERK、JNK、p38、p65 的磷酸化以及 c-myc 和 c-fos 的表达（P<0.05）。然而，用抗 CGRP 抗体和 CGRP（837）预处理可显著减弱 E-EPC-CM 对 AngII 诱导的 VSMCs 增殖的抑制作用（P<0.05）。EPCs 通过释放 CGRP 对 VSMCs 发挥抗增殖作用。
