Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Exp Gerontol. 2020 Feb;130:110793. doi: 10.1016/j.exger.2019.110793. Epub 2019 Nov 22.
Accumulating evidence from diverse experiments, including heterochronic parabiosis-the surgical joining of two animals of different ages-has highlighted the importance of systemic factors in the progressive functional decline of various organs and tissues during aging. The major metabolic pathway of tryptophan, an essential amino acid in humans, is the kynurenine pathway (KP) in which indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) catalyze the conversion of tryptophan into kynurenine. Importantly, circulating kynurenine produced by this enzymatic breakdown, as a primary driver of the aging process, has been linked to higher mortality in humans. This review discusses the potential roles of tryptophan derivatives as biomarkers for the risk of frailty in the elderly, based on human observational studies as well as the KP as a therapeutic target for age-related diseases.
越来越多的证据来自于各种实验，包括异时性联体——将两个不同年龄的动物进行手术连接——这突出了系统性因素在衰老过程中各种器官和组织进行性功能下降中的重要性。色氨酸是人体必需的氨基酸，其主要代谢途径是犬尿氨酸途径（KP），其中吲哚胺 2,3-双加氧酶（IDO）和色氨酸 2,3-双加氧酶（TDO）催化色氨酸转化为犬尿氨酸。重要的是，这种酶解产生的循环犬尿氨酸作为衰老过程的主要驱动因素，与人类更高的死亡率有关。本综述讨论了色氨酸衍生物作为老年人脆弱风险的生物标志物的潜在作用，这是基于人类观察性研究以及 KP 作为与年龄相关疾病的治疗靶点。
