The effects of SOD and catalase overexpression on the proliferation of oxLDL-treated human aortic smooth muscle cells

• Main Authors: Ting-Hui Chu, 朱庭慧
• Other Authors: Yuh-Lien Chen
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/97923342910194468220

碩士 === 國立陽明大學 === 解剖暨細胞生物學研究所 === 91 === The migration of smooth muscle cells (SMCs) into the intima, followed by their proliferation is a central theme of atherosclerosis and restenosis. Many lines suggest that the effects of antioxidant enzymes on the proliferation of SMCs play a key role in the prevention and treatment of cardiovascular disorders. The present study was designed to examine the ability of catalase and Cu/Zn superoxide dismutase (Cu/Zn SOD) expression modulating the proliferation and the production of reactive oxygen species (ROS), Human aortic smooth muscle cells (HASMCs) were infected with adenoviral vectors containing cDNA of human catalase (AdCAT) or Cu/Zn SOD (AdSOD). The infection with AdCAT or with AdSOD protein greatly increased the amount of functional catalase and SOD protein contents within HASMCs cytoplasm by Immunocytochemical staining, Western blot, and Enzyme activity assay. We examined cell survival rate by using MTT assay, cellular hydrogen peroxide and superoxide production by DCFH-DA and DHE, cellular MAPK signal pathway by Western blot, the activation of transcription factors by EMSA, and the cell proliferation by BrdU incorporation assay. HASMCs treated with 20 mg/ml oxidized low-density lipoprotein (oxLDL) for 24 hours induced cell proliferation, stimulated hydrogen peroxide and superoxide anion production, activation of MAPK (ERK1/2, p38, JNK1/2) signal pathway as well as transcription factors (AP-1 and NF-kB). Transfection with 50 MOI AdSOD, AdCAT or AdCO in 20 mg/ml oxLDL-treated HASMCs could separately reduce cellular superoxide anion and/or hydrogen peroxide production. Besides, transfection with the three kinds of cDNA could inhibit oxLDL-activated ERK1/2 and JNK 1/2 MAPK signal pathway, AP-1 and NF-kB expression and cell proliferation. HASMCs treated with MAPK inhibitors (PD98059, SB203580 or SP600125) would effectively inhibit oxLDL-activated MAPKs (ERK1/2, p38, JNK1/2) signal pathway, transcription factors of AP-1 and NF-kB expression and cell proliferation. These results suggest that antioxidant enzymes may play protective roles in the pathogenesis of atherosclerosis and restenosis by reducing ROS production and inhibiting SMC proliferation.