Toxicology of Peptide/Protein Adduction by 4-Oxononenal

描述(申请人提供)：本研究提案的目的是确定脂质过氧化的主要产物4-羟甲基烯醛(4ONE)对多肽/蛋白质的反应性。4其中一个在结构上类似于已知的细胞毒性脂质醛4-羟基壬烯醛(4HNE)，但由于其化学结构可能更具活性。4HNE对蛋白质的修饰已被认为是人类疾病(如动脉粥样硬化)发病的始动因素，然而，4HNE对多肽/蛋白质的加合作用尚未被研究或甚至被证明。为了实现本研究提案的目标，将检验以下工作假说：4 One以残基专一性共价修饰多肽和蛋白质，并能抑制代谢4HNE的酶；此外，线粒体中脂质过氧化产生的One可以修饰呼吸和代谢中重要的线粒体蛋白质/酶。为了验证这一假设，我们将进行实验，以确定4one加合物的多肽残基，表征该化合物对特定氨基酸的偏好，并确定4one加合物的化学结构。将进行工作，以确定4One是否抑制对4HNE新陈代谢至关重要的酶。此外，还将进行实验，以确定通过线粒体脂质过氧化产生的4ONE是否与呼吸和新陈代谢中重要的线粒体酶/蛋白质加成。这些目标的完成将为实现研究提案的目标提供科学数据，并通过4One评估蛋白质引入的毒理学/生理学意义。

DESCRIPTION (provided by applicant): The objective of this research proposal is to determine the reactivity of 4-oxononenal (4ONE), a major product of lipid peroxidation, toward peptides/protein. 4ONE is structurally analogous to the known cytotoxic lipid aldehyde 4-hydroxynonenal (4HNE) but is likely more reactive because of its chemical structure. Protein modification by 4HNE has been characterized and is thought to be an initiating factor in the pathogenesis of human diseases (e.g. atherosclerosis); however, the adduction of peptides/proteins by 4ONE has not been studied or even demonstrated. In order to fulfill the objective of this research proposal, the following working hypotheses will be tested: 4ONE covalently modifies peptides and proteins with residue specificity and can inhibit enzymes that metabolize 4HNE; furthermore, 4ONE generated in the mitochondria from lipid peroxidation can modify mitochonidrial proteins/enzymes important in respiration and metabolism. To test the hypothesis, experiments will be performed to identify peptide residues adducted by 4ONE, characterize the preference of the compound toward specific amino acids, and determine the chemical structure of 4ONE adducts. Work will be done to ascertain whether 4ONE inhibits enzymes important for metabolism of 4HNE. Furthermore, experiments will be conducted to determine whether 4ONE generated via mitochondrial lipid peroxidation adducts mitochondrial enzymes/proteins important in respiration and metabolism. Completion of these aims will provide scientific data to achieve the objective of the research proposal and assess the toxicological/physiological significance of protein adduction by 4ONE.