Tsikas Dimitrios, Tsikas Stefanos A, Mikuteit Marie, Ückert Stefan
Core Unit Proteomics, Institute of Toxicology, Hannover Medical School, 30623 Hannover, Germany.
Dean's of Office of Studies, Academic Controlling, Hannover Medical School, 30623 Hannover, Germany.
Biomedicines. 2023 Oct 10;11(10):2744. doi: 10.3390/biomedicines11102744.
(1) Background: Malondialdehyde (MDA) is a major and stable product of oxidative stress. MDA circulates in the blood and is excreted in the urine in its free and conjugated forms, notably with L-lysine and L-serine. MDA is the most frequently measured biomarker of oxidative stress, namely lipid peroxidation. Oxidative stress is generally assumed to be associated with disease and to increase with age. Here, we review and discuss the literature concerning circulating and excretory MDA as a biomarker of lipid peroxidation in aging subjects with regard to health and disease, such as kidney disease, erectile dysfunction, and COVID-19. (2) Methods: Scientific articles, notably those reporting on circulating (plasma, serum) and urinary MDA, which concern health and disease, and which appeared in PubMed were considered; they formed the basis for evaluating the potential increase in oxidative stress, particularly lipid peroxidation, as humans age. (3) Results and Conclusions: The results reported in the literature thus far are contradictory. The articles considered in the present study are not supportive of the general view that oxidative stress increases with aging. Many functions of several organs, including the filtration efficiency of the kidneys, are physiologically reduced in men and women as they age. This effect is likely to result in the apparent "accumulation" of biomarkers of oxidative stress, concomitantly with the "accumulation" of biomarkers of an organ's function, such as creatinine. How free and conjugated MDA forms are transported in various organs (including the brain) and how they are excreted in the urine via the kidney is not known, and investigating these questions should be the objective of forthcoming studies. The age- and gender-related increase in circulating creatinine might be a useful factor to be taken into consideration when investigating oxidative stress and aging.
(1) 背景：丙二醛（MDA）是氧化应激的一种主要且稳定的产物。MDA 在血液中循环，并以游离形式和结合形式经尿液排出，特别是与 L-赖氨酸和 L-丝氨酸结合。MDA 是氧化应激（即脂质过氧化）最常被检测的生物标志物。一般认为氧化应激与疾病相关且随年龄增长而增加。在此，我们回顾并讨论有关循环和排泄的 MDA 作为衰老个体脂质过氧化生物标志物与健康和疾病（如肾脏疾病、勃起功能障碍和 COVID-19）相关的文献。(2) 方法：考虑发表在 PubMed 上的科学文章，特别是那些报告循环（血浆、血清）和尿液中 MDA 与健康和疾病相关的文章；它们构成了评估随着人类衰老氧化应激，特别是脂质过氧化潜在增加的基础。(3) 结果与结论：迄今为止文献报道的结果相互矛盾。本研究中考虑的文章并不支持氧化应激随衰老增加的普遍观点。随着年龄增长，包括肾脏滤过效率在内的多个器官的许多功能在男性和女性中都会生理性降低。这种效应可能导致氧化应激生物标志物的明显“积累”，同时伴随着器官功能生物标志物（如肌酐）的“积累”。MDA 的游离形式和结合形式如何在各个器官（包括大脑）中运输以及它们如何通过肾脏经尿液排出尚不清楚，研究这些问题应是未来研究的目标。在研究氧化应激和衰老时，与年龄和性别相关的循环肌酐增加可能是一个需要考虑的有用因素。
