Roles of ROCK (Rho-associated protein kinase) and its Associated Pathways During Acute Vascular Thrombosis Events

• Main Authors: Yu-WenWang, 王裕文
• Other Authors: Ping-Yen Liu
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/66537744953075894573

碩士 === 國立成功大學 === 臨床醫學研究所 === 103 === Acute myocardial infarction (AMI) is a leading cause of death of cardiovascular disease (CVD) in the world. It can be triggered by thrombin, which promotes thrombosis and causes coronary artery occlusion. In early CVD, monocyte and macrophage play major role in atherosclerosis and promote plaque formation partially via Rho kinase (ROCK) signal pathway. However, it remained unknown how ROCK signaling or its associated pathways play the role on monocytes and macrophages functions during the AMI development process. Previous studies have shown that galectin-3 could promote inflammation cell migration and macrophage phagocytosis. It is possible that galectin-3 may play as the mechanism between activation of macrophages or monocytes under thrombin stimulation thus facilitate ROCK activation. Therefore, our aim is to test the interaction between galectin-3 and Rho protein signal pathway in macrophages. To investigate the ROCK activity, ROCK expression and galectin-3 secretion in macrophages, thrombin was used for the activation of THP-1 macrophage cell line. After stimulation of thrombin in macrophages, we studied the relationship between ROCK and galectin-3 secretion by western blots. Then, we tested the galectin-3 secretion among macrophage with ROCK inhibitor after thrombin stimulation. Flow cytometry and migration assay were applied to detect the M1/M2 macrophage expression distribution and migration functional changes after thrombin treatment. Finally, to prove that ROCK is important in human acute thrombotic event, we detected the phosphor-ezrin/radixin/moesin (pERM), which are the downstream molecules of ROCK, and galectin-3 expression in macrophages isolated from AMI patient and also healthy donors. We found that galectin-3 secretion was activated in macrophage after thrombin treatment peaking at 24 hours. Interestingly, Rho-associated pathway protein expressions increased after thrombin treatment earlier at 12 hours. After Rho-kinase inhibitor treatment, the expression of galectin-3 decreased in the activated macrophage. Regarding functional assay, more percentage of THP-1-derived macrophages were prone to become M1 type macrophage after thrombin treatment in flow cytometry and had greater migration ability after thrombin treatment. Finally, we proved that pERM and galectin-3 expression in AMI patient’s macrophages were higher than healthy donor’s macrophages. In conclusion, thrombin treatment can stimulate macrophage to M1 type and their migration ability, thus promote Rho-kinase signal pathway expression and galectin-3 secretion.