Gao Gufeng, Chen Ai, Yan Yan, Sagor Mohammad Ismail Hajary, Lin Weijun, Lin Huakan, Lian Guili, Xie Liangdi, Luo Li
Department of Geriatrics, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.
Fujian Hypertension Research Institute, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China.
Front Cardiovasc Med. 2025 Mar 24;12:1543319. doi: 10.3389/fcvm.2025.1543319. eCollection 2025.
Pulmonary arterial hypertension (PAH) is a severe disease marked by the remodeling of arteries due to the abnormal growth of vascular cells, including pulmonary arterial smooth muscle cells (PASMCs). The insulin receptor substrate-1 (IRS-1) plays a crucial role in the insulin signaling pathway; however, its function in PAH is still not fully understood. The objective of this research was to explore the role of the protein kinase C (PKC)/IRS-1/ERK signaling pathway in the progression of PAH and its influence on the proliferation and migration of PASMCs.
To establish the PAH model, low-dose Monocrotaline (MCT) was intraperitoneally administered to male SD rats twice a week. Four weeks following the initial treatment, measurements of mean pulmonary arterial pressure (mPAP) and the right ventricular hypertrophy index (RVHI) were conducted. Additionally, calculations were performed to determine the percentage of wall area (WA%) and wall thickness (WT%). The protein levels of PKC, p-PKC, IRS-1, p-IRS-1 (Ser318), ERK, and p-ERK in lung tissues were assessed. experiments involved stimulating PASMCs with platelet-derived growth factor-BB (PDGF-BB) to promote proliferation and migration. The impact of the PKC inhibitor Gö 6983 and IRS-1 overexpression via adenoviral vectors (AdIRS-1) on the PKC/IRS-1/ERK signaling pathway and PASMCs behavior was analyzed through Western blotting, EdU incorporation assay, and wound healing assay.
In PAH rats, there was a significant rise in mPAP and RVHI ( < 0.05), accompanied by notable pulmonary vascular remodeling. Analysis of lung tissues revealed enhanced levels of p-PKC, p-IRS-1(Ser318), and p-ERK, whereas the expression of total IRS-1 decreased significantly ( < 0.05). In PASMCs stimulated with PDGF-BB, a similar trend of increased p-PKC, p-IRS-1(Ser318), and p-ERK levels was observed, along with a decrease in IRS-1 expression. The administration of Gö 6983 or the overexpression of IRS-1 effectively inhibited the activation of the PKC/IRS-1/ERK signaling pathway, leading to reduced proliferation and migration of PASMCs compared to stimulation with PDGF-BB alone ( < 0.05).
The PKC/IRS-1/ERK signaling pathway is implicated in the abnormal proliferation and migration of PASMCs, contributing to pulmonary vascular remodeling in PAH. Targeting this pathway through PKC inhibition or IRS-1 stabilization may offer novel therapeutic strategies for PAH management.
肺动脉高压（PAH）是一种严重疾病，其特征是由于包括肺动脉平滑肌细胞（PASMCs）在内的血管细胞异常生长导致动脉重塑。胰岛素受体底物-1（IRS-1）在胰岛素信号通路中起关键作用；然而，其在PAH中的功能仍未完全明确。本研究的目的是探讨蛋白激酶C（PKC）/IRS-1/ERK信号通路在PAH进展中的作用及其对PASMCs增殖和迁移的影响。
为建立PAH模型，每周两次给雄性SD大鼠腹腔注射低剂量野百合碱（MCT）。初次治疗四周后，测量平均肺动脉压（mPAP）和右心室肥厚指数（RVHI）。此外，计算壁面积百分比（WA%）和壁厚度（WT%）。评估肺组织中PKC、p-PKC、IRS-1、p-IRS-1（Ser318）、ERK和p-ERK的蛋白水平。实验通过用血小板衍生生长因子-BB（PDGF-BB）刺激PASMCs来促进增殖和迁移。通过蛋白质印迹法、EdU掺入试验和伤口愈合试验分析PKC抑制剂Gö 6983和通过腺病毒载体（AdIRS-1）过表达IRS-1对PKC/IRS-1/ERK信号通路和PASMCs行为的影响。
在PAH大鼠中，mPAP和RVHI显著升高（<0.05），伴有明显的肺血管重塑。肺组织分析显示p-PKC、p-IRS-1（Ser318）和p-ERK水平升高，而总IRS-1表达显著降低（<0.05）。在用PDGF-BB刺激的PASMCs中，观察到p-PKC、p-IRS-1（Ser318）和p-ERK水平有类似的升高趋势，同时IRS-1表达降低。给予Gö 6983或过表达IRS-1有效抑制了PKC/IRS-1/ERK信号通路的激活，与单独用PDGF-BB刺激相比，导致PASMCs的增殖和迁移减少（<0.05）。
PKC/IRS-1/ERK信号通路与PASMCs的异常增殖和迁移有关，促成了PAH中的肺血管重塑。通过抑制PKC或稳定IRS-1来靶向该通路可能为PAH的治疗提供新的策略。
