Effects of tryptophan metabolites on IFN-induced depressive symptoms

目前推荐使用干扰素治疗慢性丙型肝炎，但在治疗期间，诸如抑郁等精神障碍在丙型肝炎患者中很常见。许多研究人员提出吲哚胺2，3-双加氧酶(IDO)1是犬尿氨酸途径的第一限速酶之一，IDO-1介导的色氨酸(Trp)代谢产物参与了干扰素诱导的抑郁的发生。在本研究中，我们测定了色氨酸及其代谢产物，并探讨了色氨酸代谢产物与干扰素治疗所致抑郁的相关性。干扰素治疗后，血清色氨酸浓度降低，部分色氨酸代谢产物升高，治疗结束后恢复至基线水平。治疗后色氨酸与代谢物的比值明显升高，尤以抑郁患者为甚。我们推测，某些色氨酸代谢产物之间的指标组合，在预测干扰素治疗引起的抑郁方面是有效的。

The therapy for chronic hepatitis C (HCV) using interferon is currently recommended, however, psychiatric disorders such as depression are frequent in HCV patients during the therapy. Many researchers propose indoleamine 2,3-dioxygenase (IDO) 1, which is one of first rate-limiting enzyme of the kynurenine pathway, and IDO1-mediated tryptophan (TRP) metabolites be implicated in the development of IFN-induced depression. In this study, we measured TRP and its metabolites and investigated correlations between TRP metabolites and depression induced by IFN therapy. Following IFN therapy, the concentration of serum TRP was reduced, while some TRP metabolites were increased, then returned to baseline values after the end of the therapy. The ratio of TRP and metabolites were significantly increased under the therapy, especially with depression. We speculate that the indexing, combination between some TRP metabolites, is effective in prediction of the depression induced by IFN therapy.