白藜芦醇抑制人肝微粒体代谢色氨酸的研究

Resveratrol inhibits metabolism of tryptophan in human liver microsomes

目的研究白藜芦醇对人肝微粒体代谢色氨酸生成犬尿氨酸的影响。方法分别考察孵育时间、色氨酸浓度、微粒体蛋白浓度,建立体外人肝微粒体孵育色氨酸代谢体系;采用高效液相色谱-串联质谱法(LC-MS/MS)检测肝微粒体孵育体系中色氨酸和犬尿氨酸浓度。基于体外人肝微粒体孵育色氨酸代谢体系探讨白藜芦醇对色氨酸代谢影响。结果色氨酸在体外人肝微粒体中最佳孵育时间为90 min,色氨酸浓度为8 mg·L^(-1),微粒体蛋白浓度为1 g·L^(-1);酶反应速率常数K m为(95.91±22.29)μmol·L^(-1),最大反应速率V max为(21.34±2.58)μmoL·g^(-1)·min^(-1)。与已知的吲哚胺2,3-双加氧酶(IDO)抑制剂Epacadostat相比,结果显示白藜芦醇也能够抑制人肝微粒体中色氨酸代谢生成犬尿氨酸且具有浓度依赖性。结论白藜芦醇具有抑制IDO活性的作用,表明IDO可能是白藜芦醇发挥药理作用的一个潜在靶点,为进一步研究白藜芦醇的药理作用及色氨酸代谢提供重要依据。

Aim To study the effect of resveratrol on the metabolism of tryptophan to kynurenine in human liver microsomes.Methods High performance liquid chromatography-tandem mass spectrometry(LC-MS/MS)was used to detect the concentration of tryptophan and kynurenine in the microsome incubation system,and the incubation time,tryptophan concentration,and microsomal protein concentration were investigated respectively.The optimal tryptophan incubation system obtained above was used to explore the effect of resveratrol on the kynurenine pathway.Results The optimal incubation time of tryptophan in human liver microsomes in vitro was 90 min,the concentration of tryptophan and liver microsomal protein was 8 mg·L^(-1) and 1 g·L^(-1),respectively.The enzyme reaction rate constant K m was 95.91±22.29μmol·L^(-1),and the maximum reaction rate V max was 21.34±2.58μmoL·g^(-1)·min^(-1).Compared with the known IDO inhibitor Epacadostat,the results showed that resveratrol could also inhibit the metabolism of tryptophan in human liver microsomes to kynurenine in a dose-dependent manner.Conclusions Resveratrol can inhibit the activity of IDO,which further confirms that IDO is an important target for resveratrol to exert pharmacological effects.This study provides an important basis for further exploration of the pharmacological function and tryptophan metabolism of resveratrol.