OXIDATIVE DNA DAMAGE & OXYSTEROL INDUCED APOPTOSIS

DNA 氧化损伤

• 批准号: 6973834
• 负责人: SYLVETTE AYALA-TORRES
• 金额: $ 4.72万
• 依托单位: UNIVERSIDAD CENTRAL DEL CARIBE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-29 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6973834
• 关键词: DNA damage; DNA repair; Puerto Rico; apoptosis; cell line; cholesterol; clinical research; free radical oxygen; gene expression; hydrogen peroxide; lymphocytic leukemia; membrane potentials; microarray technology; minority institution research support; mitochondria; mitochondrial DNA; oxidative stress; polymerase chain reaction; superoxide dismutase

The major objective of this project is to study the role of mitochondria in oxysterol-induced apoptosis of human lymphoblastic leukemia cells. Oxysterols represent a class of potent inducers of apoptosis in various cell types, particularly leukemic lymphoid cells. Oxysterols also act as powerful transcriptional regulators of genes involved in cholesterol biosynthesis, cell growth and apoptosis. Although the molecular basis of oxysterol-induced apoptosis of lymphoid cells remains unknown, some studies have suggested that oxysterol induction of apoptosis is mediated by reactive oxygen species generation. Results obtained in the previous funding cycle show that oxysterol treatment of CEM cells induces a decrease in ATP levels and loss of mitochondrial membrane potential. This project will test the hypothesis that ROS damage particularly to mitochondrial DNA plays a role in oxysterol-induced apoptosis of human leukemia cells. Our hypothesis predicts that oxidative damage to mitochondrial DNA can lead to mitochondrial dysfunction and induction of apoptosis. To test this hypothesis we will: 1) determine whether the formation and repair of oxidative damage to nuclear and mitochondrial DNA are higher in oxysterol sensitive human lymphoid cells than in oxysterol-resistant cells after exposure to oxysterols, 2) determine mitochondrial function and dysfunction in oxysterol-sensitive and resistant human lymphoid cells after exposure to oxysterols, and 3) determine the expression profile of genes involved in oxidative stress, DNA repair and apoptosis during oxysterol-induced apoptosis of lymphoid cells. This project will assist in laying the foundation for a research project directed towards the understanding of the role of mitochondria in the process of apoptosis.

本项目的主要目的是研究线粒体在氧化固醇诱导的细胞凋亡中的作用。 人淋巴母细胞白血病细胞凋亡。氧固醇代表了一类在各种细胞类型，特别是白血病淋巴样细胞中有效的细胞凋亡诱导剂。氧固醇还充当参与胆固醇生物合成、细胞生长和凋亡的基因的强有力的转录调节剂。虽然氧固醇诱导淋巴细胞凋亡的分子基础仍然未知，但一些研究表明，氧固醇诱导细胞凋亡是由活性氧产生介导的。在前一个资助周期中获得的结果表明，CEM细胞的氧固醇处理诱导ATP水平降低和线粒体膜电位丧失。该项目将测试这样的假设：活性氧损伤，特别是对线粒体DNA的损伤，在氧固醇诱导的人类白血病细胞凋亡中发挥作用。我们的假设预测，线粒体DNA的氧化损伤可导致线粒体功能障碍和诱导细胞凋亡。为了验证这个假设，我们将：1）确定在暴露于氧固醇后，对核和线粒体DNA的氧化损伤的形成和修复在氧固醇敏感的人淋巴样细胞中是否高于在氧固醇抗性细胞中，和3）确定在氧化固醇诱导的淋巴细胞凋亡过程中参与氧化应激、DNA修复和凋亡的基因的表达谱。该项目将有助于为一个旨在了解线粒体在细胞凋亡过程中的作用的研究项目奠定基础。