Aoyama Masahiro, Osuka Koji, Usuda Nobuteru, Watanabe Yasuo, Kawaguchi Reo, Nakura Takahiro, Takayasu Masakazu
1 Department of Neurological Surgery, Aichi Medical University , Aichi, Japan .
2 Department of Anatomy II, Fujita Health University School of Medicine , Aichi, Japan .
J Neurotrauma. 2015 Jul 15;32(14):1064-70. doi: 10.1089/neu.2014.3594. Epub 2015 Apr 24.
Growth factors and inflammatory cytokines activate the mitogen-activated protein kinase (MAPK) cascade. Previous studies have shown that chronic subdural hematoma (CSDH) fluid contains these factors and cytokines. In this study, expression of three major MAPK cascade transmitters in the outer membrane of CSDH was assessed. Eleven patients whose outer membrane and CSDH fluid were successfully obtained during trepanation surgery were included in this study. Expression of extracellular signal-regulated kinase (ERK), phosphorylated (p)-ERK, p38, p-p38, c-Jun N-terminal kinase (JNK), p-JNK, and actin was examined by Western blot and immunostaining. We examined whether CSDH fluid could activate MAPKs in cultured endothelial cells (ECs) or fibroblasts in vitro. Western blot analysis showed that p-ERK was present in all samples, whereas p-p38 and p-JNK were detected, but not in all cases. Immunostaining showed that all three p-MAPKs were expressed in vascular endothelium. However, only p-ERK was expressed in fibroblasts. Expression of p-extracellular signal-regulated kinase kinase (MEK) and p-ERK in ECs and fibroblasts was significantly induced immediately after treatment with CSDH fluid, whereas p-p38 and p-JNK expression was significantly induced in ECs 60 min after treatment, but not in fibroblasts. Activation of MEK was significantly inhibited by treatment with antibodies directed against interleukin-6 and vascular endothelial growth factor in ECs, but not in fibroblasts. Inflammatory cytokines and growth factors in CSDH fluids might activate major MAPKs in ECs, which might be associated with neovascularization in the outer membrane of CSDH. These MAPK pathways could become novel targets for treatment of CSDHs.
生长因子和炎性细胞因子可激活丝裂原活化蛋白激酶（MAPK）级联反应。既往研究表明，慢性硬膜下血肿（CSDH）液中含有这些因子和细胞因子。在本研究中，评估了CSDH外膜中三种主要MAPK级联反应递质的表达。本研究纳入了11例在开颅手术期间成功获取外膜和CSDH液的患者。通过蛋白质免疫印迹法和免疫染色检测细胞外信号调节激酶（ERK）、磷酸化（p）-ERK、p38、p-p38、c-Jun氨基末端激酶（JNK）、p-JNK和肌动蛋白的表达。我们在体外检测了CSDH液是否能激活培养的内皮细胞（ECs）或成纤维细胞中的MAPKs。蛋白质免疫印迹分析显示，所有样本中均存在p-ERK，而检测到了p-p38和p-JNK，但并非在所有病例中都能检测到。免疫染色显示，所有三种p-MAPKs均在血管内皮中表达。然而，仅p-ERK在成纤维细胞中表达。用CSDH液处理后，ECs和成纤维细胞中p-细胞外信号调节激酶激酶（MEK）和p-ERK的表达立即受到显著诱导，而p-p38和p-JNK的表达在处理后60分钟在ECs中受到显著诱导，但在成纤维细胞中未受到显著诱导。在ECs中，针对白细胞介素-6和血管内皮生长因子的抗体处理可显著抑制MEK的激活，但在成纤维细胞中则不然。CSDH液中的炎性细胞因子和生长因子可能激活ECs中的主要MAPKs，这可能与CSDH外膜中的新生血管形成有关。这些MAPK途径可能成为治疗CSDHs的新靶点。
