Department of Psychiatry, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga, 849-8501, Japan.
Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, Maidashi Higashi-ku 3-1-1, Fukuoka, 812-8582, Japan.
J Psychiatr Res. 2021 Jun;138:194-199. doi: 10.1016/j.jpsychires.2021.04.009. Epub 2021 Apr 9.
Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique that is considered a valuable and promising technique for improving depressive symptoms in treatment-resistant depression (TRD). However, the exact mechanism by which rTMS ameliorates depressive symptoms remains to be clarified.
The aim of the present study was to analyzed the changes in metabolites of patients with TRD in the rTMS treatment, especially focusing on the kynurenine (KYN) pathway.
Thirteen participants with TRD were enrolled in a high-frequency (10 Hz) rTMS study. Cognitive function, depressive symptoms and the concentration of plasma tryptophan (TRP) metabolites were measured at baseline and at the endpoint of rTMS treatment.
rTMS treatment significantly improved depressive symptom scores and some subscales of cognitive dysfunction. The present study has demonstrated that rTMS treatment significantly increased plasma TRP levels and significantly decreased plasma serotonin levels, while plasma KYN and kynurenic acid level as well as KYN/TRP ratio remained unchanged.
This is the first metabolomic study of patients with TRD undergoing rTMS treatment. To validate the present results, it is necessary to increase the number of cases including controls, use a sample of cerebrospinal fluid, and measure blood concentration over time in the course of rTMS treatment.
重复经颅磁刺激（rTMS）是一种非侵入性的脑刺激技术，被认为是一种有价值且有前途的技术，可以改善治疗抵抗性抑郁症（TRD）的抑郁症状。然而，rTMS 改善抑郁症状的确切机制仍需阐明。
本研究旨在分析 TRD 患者在 rTMS 治疗中的代谢物变化，特别是关注犬尿氨酸（KYN）途径。
13 名 TRD 患者参加了高频（10 Hz）rTMS 研究。在 rTMS 治疗前和治疗结束时测量认知功能、抑郁症状和血浆色氨酸（TRP）代谢物的浓度。
rTMS 治疗显著改善了抑郁症状评分和认知功能障碍的一些亚量表。本研究表明，rTMS 治疗显著增加了血浆 TRP 水平，显著降低了血浆 5-羟色胺水平，而血浆 KYN 和犬尿氨酸酸水平以及 KYN/TRP 比值保持不变。
这是 TRD 患者接受 rTMS 治疗的第一项代谢组学研究。为了验证本研究结果，有必要增加包括对照在内的病例数量，使用脑脊液样本，并在 rTMS 治疗过程中随时间测量血液浓度。
