Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, Biomedicum, Stockholm, Sweden.
Am J Physiol Cell Physiol. 2020 May 1;318(5):C818-C830. doi: 10.1152/ajpcell.00580.2019. Epub 2020 Mar 25.
Tryptophan catabolism through the kynurenine pathway generates a variety of bioactive metabolites. Physical exercise can modulate kynurenine pathway metabolism in skeletal muscle and thus change the concentrations of select compounds in peripheral tissues and in the central nervous system. Here we review recent advances in our understanding of how exercise alters tryptophan-kynurenine metabolism in muscle and its subsequent local and distal effects. We propose that the effects of kynurenine pathway metabolites on skeletal muscle, adipose tissue, immune system, and the brain suggest that some of these compounds could qualify as exercise-induced myokines. Indeed, some of the more recently discovered biological activities for kynurenines include many of the best-known benefits of exercise: improved energy homeostasis, promotion of an anti-inflammatory environment, and neuroprotection. Finally, by considering the tissue expression of the different membrane and cytosolic receptors for kynurenines, we discuss known and potential biological activities for these tryptophan metabolites.
色氨酸通过犬尿氨酸途径代谢可生成多种具有生物活性的代谢产物。体育锻炼可以调节骨骼肌中的犬尿氨酸代谢途径，从而改变外周组织和中枢神经系统中特定化合物的浓度。本文我们综述了关于运动如何改变肌肉中的色氨酸-犬尿氨酸代谢以及随后的局部和远端效应的最新研究进展。我们提出，犬尿氨酸途径代谢产物对骨骼肌、脂肪组织、免疫系统和大脑的影响表明，其中一些化合物可能符合运动诱导肌因子的标准。事实上，犬尿氨酸的一些最近发现的生物学活性包括运动的许多众所周知的益处：改善能量平衡、促进抗炎环境和神经保护。最后，通过考虑犬尿氨酸的不同膜和胞质受体的组织表达，我们讨论了这些色氨酸代谢产物的已知和潜在生物学活性。
