Schizophrenia Program, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Department of Psychiatry, Jinhua Second Hospital, Zhejiang, China.
J Affect Disord. 2020 Jul 1;272:24-27. doi: 10.1016/j.jad.2020.03.121. Epub 2020 Apr 29.
Methylenetetrahydrofolate reductase (MTHFR) is the key enzyme of folate metabolism in the process of one-carbon cycle and its deficiency results in elevated homocysteine concentration. In this study, we hypothesized that MTHFR C677T polymorphism and homocysteine concentration may play important roles in the development of depressive symptoms in schizophrenia.
We recruited 715 patients with stable schizophrenia, and among them, 197 schizophrenia patients under olanzapine monotherapy were enrolled for homocysteine concentration analysis. The Positive and Negative Syndrome Scale (PANSS) and Calgary Depression Scale for Schizophrenia (CDSS) were employed to evaluate psychiatric and depressive symptoms.
When the 715 schizophrenia patients were evaluated by CDSS, 326 individuals (45.6%) had depressive symptoms. No significant differences were observed in C677T genotype and allele distributions between the schizophrenia with or without depression groups. Schizophrenia patients with depression have higher levels of homocysteine than those without depression (P = 0.019). There was a positive correlation between the homocysteine levels and CDSS score (r = 0.22, P = 0.002).
Our findings suggested that higher levels of homocysteine may be a risk factor for the development of depressive symptoms in schizophrenia patients.
亚甲基四氢叶酸还原酶（MTHFR）是叶酸代谢过程中一碳循环的关键酶，其缺乏会导致同型半胱氨酸浓度升高。在这项研究中，我们假设 MTHFR C677T 多态性和同型半胱氨酸浓度可能在精神分裂症患者抑郁症状的发展中起重要作用。
我们招募了 715 例稳定的精神分裂症患者，其中 197 例接受奥氮平单药治疗的精神分裂症患者纳入同型半胱氨酸浓度分析。采用阳性和阴性症状量表（PANSS）和 Calgary 精神分裂症抑郁量表（CDSS）评估精神和抑郁症状。
当用 CDSS 评估 715 例精神分裂症患者时，326 例（45.6%）有抑郁症状。抑郁组和非抑郁组的 MTHFR C677T 基因型和等位基因分布无显著差异。有抑郁症状的精神分裂症患者的同型半胱氨酸水平高于无抑郁症状的患者（P=0.019）。同型半胱氨酸水平与 CDSS 评分呈正相关（r=0.22，P=0.002）。
我们的研究结果表明，较高的同型半胱氨酸水平可能是精神分裂症患者发生抑郁症状的一个危险因素。
