Jiang Xiaowei, Guo Yingrui, Jia Linna, Zhu Yue, Sun Qikun, Kong Lingtao, Wu Feng, Tang Yanqing
Brain Function Research Section, Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, China.
Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, China.
Front Psychiatry. 2022 Apr 7;13:861881. doi: 10.3389/fpsyt.2022.861881. eCollection 2022.
Bipolar disorder (BD) has a higher lifetime rate of suicide attempts (SA) than other psychiatric disorders. Furthermore, BD patients with SA (BD + S) are prone to a worse quality of life. However, the pathophysiology of BD + S is poorly understood. To further reveal the potential mechanisms of BD + S, abnormalities in peripheral plasma inflammatory cytokines and brain white matter (WM) in BD + S, as well as the correlation between them are investigated.
We tested the levels of TNF-α, IL-1β, and IL-6 in peripheral plasma and collected the diffusion tensor imaging (DTI) data from 14 BD + S, 24 BD patients without SA (BD-S), and 26 healthy controls (HCs). The three groups were matched by age and gender. The levels of TNF-α, IL-1β, and IL-6 were detected by Luminex multifactor detection technology, and the fractional anisotropy (FA) values were employed to depict the alterations of WM. Partial correlation analyses were conducted to detect correlations between levels of TNF-α, IL-1β, and IL-6 and changes of WM, and the relationships between severity of clinical symptoms, including scores of HAMD-17 and YMRS, and cytokine levels or FA values in all groups.
For plasma inflammatory cytokines, there was no significant difference in their levels except for IL-6 among the three groups. analyses revealed that increased IL-6 level was only detected in BD + S ( < 0.05, Bonferroni correction). For DTI, BD + S showed specifically decreased FA in the bilateral middle cerebellar peduncle and the left superior corona radiata compared to BD-S and HCs ( < 0.05, Bonferroni correction). Additionally, both BD + S and BD-S groups revealed decreased FA in the bilateral body and genu of corpus callosum (CC) compared to HCs ( < 0.05, Bonferroni correction). No significant correlation between plasma inflammatory cytokines and WM integrity was found. In the BD + S group, we found negative correlation between the scores of YMRS and FA values of the left middle cerebellar peduncle ( = -0.74, = 0.035).
The inflammation and impaired WM integrity may provide a scientific basis to understand the potential mechanisms of BD + S.
双相情感障碍（BD）患者终生自杀未遂（SA）发生率高于其他精神疾病。此外，有自杀未遂的BD患者（BD+S）生活质量较差。然而，BD+S的病理生理学尚不清楚。为进一步揭示BD+S的潜在机制，本研究调查了BD+S患者外周血浆炎症细胞因子和脑白质（WM）的异常情况及其相关性。
检测14例BD+S患者、24例无自杀未遂的BD患者（BD-S）和26例健康对照（HCs）外周血浆中TNF-α、IL-1β和IL-6水平，并收集其扩散张量成像（DTI）数据。三组在年龄和性别上相匹配。采用Luminex多因子检测技术检测TNF-α、IL-1β和IL-6水平，用分数各向异性（FA）值描述WM的改变。进行偏相关分析以检测TNF-α、IL-1β和IL-6水平与WM变化之间的相关性，以及所有组中临床症状严重程度（包括HAMD-17和YMRS评分）与细胞因子水平或FA值之间的关系。
对于血浆炎症细胞因子，三组中除IL-6外其水平无显著差异。分析显示，仅在BD+S组中检测到IL-6水平升高（P<0.05，Bonferroni校正）。对于DTI，与BD-S组和HCs相比，BD+S组双侧小脑中脚和左侧放射冠FA值明显降低（P<0.05，Bonferroni校正）。此外，与HCs相比，BD+S组和BD-S组双侧胼胝体（CC）体部和膝部FA值均降低（P<0.05，Bonferroni校正）。未发现血浆炎症细胞因子与WM完整性之间存在显著相关性。在BD+S组中，我们发现YMRS评分与左侧小脑中脚FA值呈负相关（r=-0.74，P=0.035）。
炎症和WM完整性受损可能为理解BD+S的潜在机制提供科学依据。
