Pan Lemen, Ni Haizhen, Jin Wenxu, Su Xiang
Department of Vascular Surgery, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
Cardiovasc Diagn Ther. 2020 Aug;10(4):658-666. doi: 10.21037/cdt-20-345.
Connexins (Cxs) are reported to participate in atherosclerosis associated intimal hyperplasia (IH), while their function involved in the balloon injury (BI) induced IH and restenosis is less reported.
Forty-eight male Sprague-Dawley rats were randomly assigned to not injured (NI) group and BI group, which were further administrated with ERK-inhibitor U0216 and Akt-inhibitor MIK2206. Western blot and RT-PCR were utilized to detect the expression of Cx30, Cx37, Cx40, and Cx43 at 6 hours, 24 hours, 7 days, and 14 days post-surgery. H&E staining and related intima area, media area, and luminal area measurement were applied to indicate neointima formation and IH. ERK and Akt phosphorylation levels and proliferating cell nuclear antigen (PCNA) immunostaining were also detected.
Among the four Cxs detected, Cx37 showed down-regulated, and Cx43 showed up-regulated temporal expression pattern in BI rats with confirmed neointima formation. Up-regulated p-ERK (P<0.01) and p-Akt (P<0.01) can be detected in BI rats compared with NI rats. Meanwhile, U0216 and MIK2206 can significantly reduce Cx43 expression and increase CX37 expression accompanied with reduced neointima formation and PCNA staining (P<0.05 or P<0.01) in BI rats.
ERK or Akt inhibition can alleviate BI-induced IH via up-regulation of Cx37 and down-regulation of Cx43.
据报道，连接蛋白（Cxs）参与动脉粥样硬化相关的内膜增生（IH），而其在球囊损伤（BI）诱导的IH和再狭窄中的作用报道较少。
48只雄性Sprague-Dawley大鼠随机分为未损伤（NI）组和BI组，并进一步给予ERK抑制剂U0216和Akt抑制剂MIK2206。采用蛋白质免疫印迹法和逆转录-聚合酶链反应（RT-PCR）检测术后6小时、24小时、7天和14天Cx30、Cx37、Cx40和Cx43的表达。应用苏木精-伊红（H&E）染色及相关内膜面积、中膜面积和管腔面积测量来指示新生内膜形成和IH。还检测了ERK和Akt磷酸化水平以及增殖细胞核抗原（PCNA）免疫染色。
在检测的四种Cxs中，Cx37在有新生内膜形成的BI大鼠中呈下调表达模式，而Cx43呈上调表达模式。与NI大鼠相比，在BI大鼠中可检测到p-ERK（P<0.01）和p-Akt（P<0.01）上调。同时，U0216和MIK2206可显著降低BI大鼠中Cx43的表达并增加Cx37的表达，同时新生内膜形成和PCNA染色减少（P<0.05或P<0.01）。
抑制ERK或Akt可通过上调Cx37和下调Cx43来减轻BI诱导的IH。
