Gelsolin Affects Cell Morphology and Caveolin Signaling Against Hydrogen Peroxide-induced Oxidative Stress in H9c2 Rat Cardiomyoblasts
| Autor: | Shu-Ting He, 何舒婷 |
|---|---|
| Rok vydání: | 2013 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 101 Gelsolin (GSN) is a Ca2+-dependent actin-regulatory protein that can sever actin filaments and cap the quickly growing ends of filaments, and thus promoting actin disassembly. Accordingly, GSN plays a role in the organization of the cytoskeleton assembly/disassembly, cell motility, cell growth, and apoptosis. The biological function of GSN and its interaction with scafold proteins-caveolin in cardiac cells is not clear thus far. Caveolin (cav) is known to play an important role in myocardial protection signaling for controling intracellular SOD activity and modulating oxidative stress in cardic cells. It is of interest to define the role of GSN and to establiah relationship between the stress fiber formation by cytoskeleton and the expression of Cavs in cardic cells. In this study, GSN over-expressed (GSN op) and GSN silenced (si-GSN) H9c2 rat cardiomyoblasts in a simulated condition with oxidative stress by hydrogen peroxide were used to explore the potential mechanism of GSN in cardiac protection aganist oxidative stress. A pcDNA6-GSN containing full-length human GSN transfected into H9c2 cells caused increases in intracellular calcium concentration and alteration of cell morphology and actin filament－associated structure. GSN over-expressing cells changed morphology to a “shorter and broader” form, while GSN silencing cells displayed a less change in cell shape as compared with wild-type cells. MTT assay and flow cytometry indicated that GSN over-expression slowed down cell proliferation and increased cell populations sorted in S and G2 phases. These results suggested that GSN over-expression may enhance the ability of capping and severing F-actin such as to increase dissembly of actin filaments, and to slow down cell division and cell growth. In addition, GSN was found to modulate the expression of Cavs and their cellular functions in protecting cardic cells from oxidative stress induced by H2O2. The experiments designed to investigate the impact of an increase intracellular Cavs on anti-oxidative effects in H9c2 cells showed that GSN over-expressing cells increased their anti-oxidative capacity in H2O2-induced oxidative stress by preventing the down-regulation of Cavs, and by attenuating the H2O2-increased intracellular ROS levels, and by elevating mRNA expression for associated anti-oxidants such as HO-1, Cu-SOD, and catalase, and by increasing anti-oxidative SOD activity. Taken together, the results found in this study suggested that GSN might induce remodeling of actin filaments and that linked to mediate the Cav signaling for anti-oxidative effects in cardiac cells. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|