Redox Properties of Tryptophan Metabolism and the Concept of Tryptophan Use in Pregnancy

Abstract

During pregnancy, tryptophan (Trp) is required for several purposes, and Trp metabolism varies over time in the mother and fetus. Increased oxidative stress (OS) with high metabolic, energy and oxygen demands during normal pregnancy or in pregnancy-associated disorders has been reported. Taking the antioxidant properties of Trp and its metabolites into consideration, we made four hypotheses. First, the use of Trp and its metabolites is optional based on their antioxidant properties during pregnancy. Second, dynamic Trp metabolism is an accommodation mechanism in response to OS. Third, regulation of Trp metabolism could be used to control/attenuate OS according to variations in Trp metabolism during pregnancy. Fourth, OS-mediated injury could be alleviated by regulation of Trp metabolism in pregnancy-associated disorders. Future studies in normal/abnormal pregnancies and in associated disorders should include measurements of free Trp, total Trp, Trp metabolites, and activities of Trp-degrading enzymes in plasma. Abnormal pregnancies and some associated disorders may be associated with disordered Trp metabolism related to OS. Mounting evidence suggests that the investigation of the use of Trp and its metabolites in pregnancy will be meanful.

Impact of the Gut Microbiota on Intestinal Immunity Mediated by Tryptophan Metabolism

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Regulation of functional amino acids on oxidative stress in pigs

“…色 氨 酸 及 其 代 谢 产 物 也 被 报 道 具 有 抗 氧 化 特 性 [69] . 研究显示敌草快诱导的仔猪氧化应激显著降低 了血液色氨酸含量 [70] , 而哺乳仔猪饲喂色氨酸抑制了 应激激素的分泌, 并提高了生产性能 [71] .…”

Negative effects on newborn piglets caused by excess dietary tryptophan in the morning in sows

“…Trp can be directly transported from the maternal to the fetal circulation through the placenta to affect fetal growth and development during pregnancy . In addition, maternal Trp infusion leads to a significant increase in Trp metabolites, such as kynurenine (KYN), KYNA and QA in the fetal plasma …”

“…2 In addition, maternal Trp infusion leads to a significant increase in Trp metabolites, such as kynurenine (KYN), KYNA and QA in the fetal plasma. 3,4 In addition to the above-mentioned functions, a link between Trp metabolism and the circadian rhythm has been reported. 5 During pregnancy, Trp derivatives, such as serotonin and melatonin, play important roles in circadian rhythms.…”