Shen Zonglin, Lu Yi, Jiang Hongyan, Ye Jing, Zhou Cong, He Mengxin, Li Na, Xu Xiufeng, Cheng Yuqi
Departments of Psychiatry.
Medical Imaging, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China.
Neuroreport. 2020 Nov 4;31(16):1146-1153. doi: 10.1097/WNR.0000000000001528.
The neuro-anatomical substrates of major depressive disorder (MDD) remain poorly understood. Brain-derived neurotrophic factor (BDNF) gene polymorphism (Val66Met/rs6265) is associated with neuro-plasticity and development. In the present study, we explore the influence of BDNF gene polymorphism on cortical thickness in nonelderly, first episode, drug-naive patients with MDD.
Two hundred and sixteen participants (105 MDD patients and 111 healthy controls) were divided into subgroups based on the BDNF genotype. High-resolution MRI was obtained in all participants. A relationship of BDNF Val66Met gene polymorphism and cortical thickness was investigated.
The significant main effect of diagnosis was identified in the left rostal anterior cingulate (rACC), right inferior temporal and right lateral orbitofrontal (lOFC). The main effect of the genotype was observed in the left posterior cingulate cortex. The diagnosis-by-genotype interaction effect was found located in the left rACC. MDD patients who were Met-carriers exhibited thinner cortical thickness in the left rACC than healthy controls Met-carriers. Neither the symptom severity nor the illness duration was correlated significantly with cortical thickness.
Our findings suggested that the BDNF gene polymorphism was associated with cortical thickness alterations of the left rACC in MDD patients, and genotype that carries Met may serve as a vulnerability factor in MDD regarding the cortical thickness loss in the left rACC. This finding can be considered as a supportive evidence for the neurotrophic factor hypothesis of depression.
重度抑郁症（MDD）的神经解剖学基础仍了解不足。脑源性神经营养因子（BDNF）基因多态性（Val66Met/rs6265）与神经可塑性和发育相关。在本研究中，我们探讨BDNF基因多态性对非老年、首发、未用药的MDD患者皮质厚度的影响。
216名参与者（105名MDD患者和111名健康对照）根据BDNF基因型分为亚组。所有参与者均接受高分辨率MRI检查。研究BDNF Val66Met基因多态性与皮质厚度的关系。
在左侧喙部前扣带回（rACC）、右侧颞下回和右侧外侧眶额皮质（lOFC）发现诊断的显著主效应。在左侧后扣带回皮质观察到基因型的主效应。诊断与基因型的交互效应位于左侧rACC。携带Met的MDD患者左侧rACC的皮质厚度比健康对照携带Met者更薄。症状严重程度和病程均与皮质厚度无显著相关性。
我们的研究结果表明，BDNF基因多态性与MDD患者左侧rACC的皮质厚度改变有关，携带Met的基因型可能是MDD患者左侧rACC皮质厚度丧失的一个易患因素。这一发现可被视为抑郁症神经营养因子假说的支持性证据。
