Hoekstra Pieter J, Anderson George M, Troost Pieter W, Kallenberg Cees G M, Minderaa Ruud B
Department of Psychiatry, University Medical Center Groningen, University of Groningen, P.O. Box 660, 9700 AR, Groningen, The Netherlands.
Eur Child Adolesc Psychiatry. 2007 Jun;16 Suppl 1:71-7. doi: 10.1007/s00787-007-1009-1.
Increased plasma kynurenine has been reported in tic disorder patients, and this observation has been suggested to be indicative of immune dysregulation. In the present study, we examined plasma levels of kynurenine and related molecules in a group of tic disorder patients.
Plasma concentrations of tryptophan, kynurenine, cortisol, and neopterin were determined in Dutch tic disorder patients (N = 59), and healthy volunteers (N = 32). Group means were compared and age-controlled intra-individual correlations between tic severity and plasma levels of these molecules were examined.
No significant differences were found between patient and control groups in plasma levels of tryptophan, kynurenine, and cortisol concentrations, nor in the kynurenine/tryptophan ratio. However, neopterin was significantly (p = 0.035) higher in patients (mean = 5.13 nmol/l) than in controls (mean = 3.30 nmol/l). Plasma levels of these molecules did not correlate with tic severity, with the exception of tryptophan (r = -0.289, p = 0.049). In patients, plasma neopterin correlated with kynurenine (r = 0.438, p = 0.002); in healthy subjects, tryptophan correlated with kynurenine (r = 0.670, p < 0.001).
While the observed elevation in plasma neopterin is consistent with immune activation in a subset of tic disorder patients, metabolism of tryptophan through the kynurenine pathway appears to be unaltered in tic disorder patients.
有报道称抽动障碍患者血浆犬尿氨酸水平升高，这一观察结果提示可能存在免疫失调。在本研究中，我们检测了一组抽动障碍患者血浆中犬尿氨酸及相关分子的水平。
测定了荷兰抽动障碍患者（N = 59）和健康志愿者（N = 32）血浆中色氨酸、犬尿氨酸、皮质醇和新蝶呤的浓度。比较了两组的均值，并检测了抽动严重程度与这些分子血浆水平之间的年龄校正个体内相关性。
患者组和对照组在色氨酸、犬尿氨酸和皮质醇浓度的血浆水平以及犬尿氨酸/色氨酸比值方面均未发现显著差异。然而，患者组的新蝶呤水平（均值 = 5.13 nmol/l）显著高于对照组（均值 = 3.30 nmol/l，p = 0.035）。除色氨酸外（r = -0.289，p = 0.049），这些分子的血浆水平与抽动严重程度无关。在患者中，血浆新蝶呤与犬尿氨酸相关（r = 0.438，p = 0.002）；在健康受试者中，色氨酸与犬尿氨酸相关（r = 0.670，p < 0.001）。
虽然观察到的血浆新蝶呤升高与部分抽动障碍患者免疫激活一致，但抽动障碍患者中色氨酸通过犬尿氨酸途径的代谢似乎未改变。
