Lee Sang Mook, Choi Hyunsoo, Yang Geumjin, Park Ki Cheol, Jeong Sikyoung, Hong Sungyoup
Department of Anaesthesia and Pain Medicine, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seocho-gu, Seoul 137‑701, Republic of Korea.
Clinical Research Institute, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seocho-gu, Seoul 137‑701, Republic of Korea.
Mol Med Rep. 2014 Jul;10(1):292-300. doi: 10.3892/mmr.2014.2155. Epub 2014 Apr 15.
Intravenous (IV) infusion of oleic acid (OA) distributes OA microemboli in the pulmonary capillaries, which results in severe vascular congestion, hemorrhage vascular congestion, interstitial edema, intravascular coagulation and bleeding. The immune response to acute lung injury (ALI) is known to be associated with rapid and widespread changes in microRNA (miRNA) expression in the lung. The present study of a model of rat lung injury aimed to investigate how the lung miRNA profile changes to mediate ALI. For the induction of ALI, OA (200 µl/kg) suspended in 20% ethyl alcohol was injected through the tail vein for 20 min. Lung tissue samples were acquired at 3, 6 and 24 h, and miRNA microarray and quantitative polymerase chain reaction were performed using these samples. The activation of phosphatase and tensin homolog (PTEN), protein kinase B (Akt), extracellular signal-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK) were analyzed by western blot analysis. There were 75 miRNAs that demonstrated >1.5‑fold changes in expression levels. miR-101a was highly upregulated at 3 h. miR-21 was upregulated in the OA group throughout the 24 h following OA challenge. miR-1 was the most downregulated miRNA at 24 h. In order to examine the expression levels of PTEN and Akt as targets of miR-21, western blot analysis was performed. At 3 h, the levels of PTEN were attenuated in the OA group as compared with those in the control group; however, p-Akt/Akt levels were increased at 3 h for the OA group. PTEN and p-Akt/Akt were significantly higher in the OA group at 3 h and were rapidly decreased at 6 h. The immunohistochemical stain of α-smooth muscle actin in the bronchial and alveolar wall increased 24 h after OA‑induced ALI. These results indicated that the profile of miRNAs dynamically changed throughout the OA-induced ALI process, and mitogen-activated protein kinase activation, PTEN/Akt pathway alteration and smooth muscle actin activation were observed in this ALI model.
静脉注射油酸（OA）会在肺毛细血管中分布OA微栓子，这会导致严重的血管充血、出血性血管充血、间质水肿、血管内凝血和出血。已知对急性肺损伤（ALI）的免疫反应与肺中微小RNA（miRNA）表达的快速广泛变化有关。本大鼠肺损伤模型研究旨在探讨肺miRNA谱如何变化以介导ALI。为诱导ALI，将悬浮于20%乙醇中的OA（200 μl/kg）经尾静脉注射20分钟。在3、6和24小时采集肺组织样本，并使用这些样本进行miRNA微阵列和定量聚合酶链反应。通过蛋白质印迹分析磷酸酶和张力蛋白同源物（PTEN）、蛋白激酶B（Akt）、细胞外信号调节激酶（ERK）和c-Jun氨基末端激酶（JNK）的激活情况。有75种miRNA的表达水平变化超过1.5倍。miR-101a在3小时时高度上调。miR-21在OA攻击后的24小时内，OA组均上调。miR-1是24小时时下调最明显的miRNA。为检测作为miR-21靶标的PTEN和Akt的表达水平，进行了蛋白质印迹分析。在3小时时，OA组的PTEN水平与对照组相比有所降低；然而，OA组在3小时时p-Akt/Akt水平升高。OA组在3小时时PTEN和p-Akt/Akt显著升高，并在6小时时迅速下降。OA诱导ALI后24小时，支气管和肺泡壁中α-平滑肌肌动蛋白的免疫组织化学染色增加。这些结果表明，在OA诱导的ALI过程中，miRNA谱动态变化，并且在该ALI模型中观察到丝裂原活化蛋白激酶激活、PTEN/Akt途径改变和平滑肌肌动蛋白激活。
