Wu Yaojiong, Wu Jin, Lee Daniel Y, Yee Albert, Cao Liu, Zhang Yaou, Kiani Chris, Yang Burton B
Sunnybrook and Women's College Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, Canada M4N 3M5.
Matrix Biol. 2005 Feb;24(1):3-13. doi: 10.1016/j.matbio.2004.11.007.
Oxidant injury plays a critical role in the degenerative changes that are characterized by a decline in parenchymal cell numbers and viability, and occur with aging and in the etiology of many diseases. The extracellular proteoglycan versican is widely distributed in the extracellular matrix surrounding the cells. This study examines whether versican plays a role in protecting cells from free radical-induced apoptosis. Stable expression of versican or its C-terminal domain significantly decreased H(2)O(2)-induced cellular apoptosis. Cells in adherent monolayer were more resistant to H(2)O(2)-induced apoptosis than cells cultured in suspension. While vigorous trypsinization caused integrin cleavage and rendered the cells more susceptible to H(2)O(2)-induced damages, expression of versican or its C-terminal domain enhanced cell attachment and expression of beta1 integrin and fibronectin. Enhanced cell-matrix interaction by addition of manganese (MnCl(2)) to cultures also significantly diminished H(2)O(2)-induced apoptosis. The results suggest that versican plays an important role in reducing oxidant injury through an enhancement of cell-matrix interaction.
氧化损伤在以实质细胞数量和活力下降为特征的退行性变化中起关键作用,这些变化随着衰老以及在许多疾病的病因中出现。细胞外蛋白聚糖多功能蛋白聚糖广泛分布于细胞周围的细胞外基质中。本研究检测多功能蛋白聚糖是否在保护细胞免受自由基诱导的凋亡中发挥作用。多功能蛋白聚糖或其C末端结构域的稳定表达显著降低了过氧化氢诱导的细胞凋亡。贴壁单层培养的细胞比悬浮培养的细胞对过氧化氢诱导的凋亡更具抗性。剧烈的胰蛋白酶消化导致整合素裂解,使细胞对过氧化氢诱导的损伤更敏感,而多功能蛋白聚糖或其C末端结构域的表达增强了细胞黏附以及β1整合素和纤连蛋白的表达。通过向培养物中添加锰(氯化锰)增强细胞-基质相互作用也显著减少了过氧化氢诱导的凋亡。结果表明,多功能蛋白聚糖通过增强细胞-基质相互作用在减少氧化损伤中起重要作用。