Pei Changan, Qin Shiyong, Wang Minghai, Zhang Shuguang
Department of Vascular Surgery, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China.
Department of Vascular Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong 250014, P.R. China.
Mol Med Rep. 2015 Nov;12(5):7310-6. doi: 10.3892/mmr.2015.4365. Epub 2015 Sep 25.
Vascular disorders, including hypertension, atherosclerosis and restenosis, arise from dysregulation of vascular smooth muscle cell (VSMC) differentiation, which can be controlled by regulatory factors. The present study investigated the regulatory mechanism of the phenotypic transformation of human VSMCs by NELIN in order to evaluate its potential as a preventive and therapeutic of vascular disorders. An in vitro model of NELIN‑overexpressing VSMCs was prepared by transfection with a lentiviral (LV) vector (NELIN‑VSMCs) and NELIN was slienced using an a lentiviral vector with small interfering (si)RNA in another group (LV‑NELIN‑siRNA‑VSMCs). The effects of NELIN overexpression or knockdown on the phenotypic transformation of human VSMCs were observed, and its regulatory mechanism was studied. Compared with the control group, cells in the NELIN‑VSMCs group presented a contractile phenotype with a significant increase of NELIN mRNA, NELIN protein, smooth muscle (SM)α‑actin and total Ras homolog gene family member A (RhoA) protein expression. The intra‑nuclear translocation of SMα‑actin‑serum response factor (SMα‑actin‑SRF) occurred in these cells simultaneously. Following exposure to Rho kinsase inhibitor Y‑27632, SRF and SMα‑actin expression decreased. However, cells in the LV‑NELIN‑siRNA‑VSMCs group presented a synthetic phenotype, and the expression of NELIN mRNA, NELIN protein, SMα‑actin protein and total RhoA protein was decreased. The occurrence of SRF extra‑nuclear translocation was observed. In conclusion, the present study suggested that NELIN was able to activate regulatory factors of SMα‑actin, RhoA and SRF successively in human VSMCs cultured in vitro. Furthermore, NELIN‑induced phenotypic transformation of human VSMCs was regulated via the RhoA/SRF signaling pathway. The results of the present study provide a foundation for the use of NELIN in preventive and therapeutic treatment of vascular remodeling diseases, including varicosity and atherosclerosis.
血管疾病，包括高血压、动脉粥样硬化和再狭窄，是由血管平滑肌细胞（VSMC）分化失调引起的，而这种失调可由调节因子控制。本研究调查了NELIN对人VSMC表型转化的调节机制，以评估其作为血管疾病预防和治疗手段的潜力。通过用慢病毒（LV）载体转染制备NELIN过表达VSMC的体外模型（NELIN-VSMCs），在另一组中使用带有小干扰（si）RNA的慢病毒载体使NELIN沉默（LV-NELIN-siRNA-VSMCs）。观察NELIN过表达或敲低对人VSMC表型转化的影响，并研究其调节机制。与对照组相比，NELIN-VSMCs组细胞呈现收缩表型，NELIN mRNA、NELIN蛋白、平滑肌（SM）α-肌动蛋白和总Ras同源基因家族成员A（RhoA）蛋白表达显著增加。这些细胞中同时发生了SMα-肌动蛋白-血清反应因子（SMα-肌动蛋白-SRF）的核内转位。在暴露于Rho激酶抑制剂Y-27632后，SRF和SMα-肌动蛋白表达降低。然而，LV-NELIN-siRNA-VSMCs组细胞呈现合成表型，NELIN mRNA、NELIN蛋白、SMα-肌动蛋白蛋白和总RhoA蛋白表达降低。观察到SRF核外转位的发生。总之，本研究表明，NELIN能够在体外培养的人VSMC中依次激活SMα-肌动蛋白、RhoA和SRF的调节因子。此外，NELIN诱导的人VSMC表型转化是通过RhoA/SRF信号通路调节的。本研究结果为NELIN用于包括静脉曲张和动脉粥样硬化在内的血管重塑疾病的预防和治疗提供了基础。
