Department of Child and Adolescent Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan; Institute for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Schizophr Res. 2018 Feb;192:391-397. doi: 10.1016/j.schres.2017.03.041. Epub 2017 Mar 28.
Oxidative stress has been implicated in the psychopathology of schizophrenia. Cysteine, a semi-essential amino acid, is the precursor of the antioxidant glutathione. The aim of this study was to investigate the differences in serum levels of cysteine between patients with schizophrenia and healthy controls. The relationships between levels of cysteine, psychopathology and cognitive function were also explored.
We recruited 65 patients with schizophrenia and 65 age- and gender-matched healthy controls. Blood samples were collected to determine the serum levels of cysteine and plasma levels of metabolic parameters. The cognitive function of participants was assessed using the Brief Assessment of Cognition in Schizophrenia (BACS). The psychopathology of schizophrenic patients was evaluated using the Positive and Negative Syndrome Scale.
Serum cysteine levels were significantly higher in schizophrenic patients than in controls (P<0.001). In patients with schizophrenia, serum levels of cysteine were positively correlated with cognitive function in terms of verbal memory (P=0.013), working memory (P=0.004), verbal fluency (P=0.027), attention and processing speed (P=0.025), executive function (P=0.024) and the composite score on the BACS (P=0.013). In healthy controls, no significant correlation was observed between cysteine level and cognitive function.
These findings suggest that oxidative stress may be involved in the pathogenesis of schizophrenia, and compensatory elevated levels of cysteine may serve as an indicator of cognition preservation. Further prospective studies are warranted to investigate the dynamic alterations in cysteine and the underlying pathophysiology of schizophrenia.
氧化应激与精神分裂症的发病机制有关。半必需氨基酸半胱氨酸是抗氧化剂谷胱甘肽的前体。本研究旨在探讨精神分裂症患者与健康对照组之间血清半胱氨酸水平的差异。还探讨了半胱氨酸水平与精神病理学和认知功能之间的关系。
我们招募了 65 名精神分裂症患者和 65 名年龄和性别匹配的健康对照者。采集血样以确定血清半胱氨酸水平和血浆代谢参数水平。使用简明精神分裂症认知评估量表（BACS）评估参与者的认知功能。使用阳性和阴性综合征量表（PANSS）评估精神分裂症患者的精神病理学。
精神分裂症患者的血清半胱氨酸水平明显高于对照组（P<0.001）。在精神分裂症患者中，血清半胱氨酸水平与认知功能呈正相关，具体表现在言语记忆（P=0.013）、工作记忆（P=0.004）、言语流畅性（P=0.027）、注意力和处理速度（P=0.025）、执行功能（P=0.024）和 BACS 综合评分（P=0.013）。在健康对照组中，未观察到半胱氨酸水平与认知功能之间存在显著相关性。
这些发现表明氧化应激可能参与精神分裂症的发病机制，而代偿性升高的半胱氨酸水平可能是认知保护的指标。需要进一步的前瞻性研究来研究半胱氨酸的动态变化和精神分裂症的潜在病理生理学。
