Liu Yang, Gao Yuan, Ma Zhidong, Zhang Qingge, Sun Ruiqiang, Wang Ling, Zhao Sishun, Li Changjiang, Lian Bo, Sun Hongwei, Sun Lin
School of Psychology, Shandong Second Medical University, 7166# Baotong West Street, Weifang, Shandong, 261053, P. R. China.
School of Clinical Medicine, Shandong Second Medical University, 7166# Baotong West Street, Weifang, Shandong, 261053, P. R. China.
Cogn Affect Behav Neurosci. 2025 Apr;25(2):515-530. doi: 10.3758/s13415-024-01244-2. Epub 2025 Jan 22.
Post-traumatic stress disorder (PTSD) is a serious psychiatric disorder that occurs after an individual has witnessed or experienced a major traumatic event. Emotional contagion seems to play an important role in witnessing trauma, highlighting the importance of understanding the neurobiological consequences of psychological or emotional stress and its impact on the individual's mental health. Therefore, understanding the relationship between emotional contagion and PTSD susceptibility and the abnormal neurobiological and behavioral changes behind it could help find effective molecular treatment targets.
The formalin pain test was used to distinguish the level of emotional contagion in observer mice, dividing them into quartiles according to their pain response. The upper and lower quartiles were the emotional contagion-prone (ECP) and -resistant (ECR) groups, respectively. The vicarious social defeat stress (VSDS) procedure was used to establish PTSD models in mice with various emotional contagion levels when witnessing stress. Open field, elevated plus maze, social interaction test, and forced swimming test were used to examine PTSD-like symptoms. Changes in the medial prefrontal cortex (mPFC) mRNA expression of brain-derived neurotrophic factor (BDNF) and oxytocin receptor (OTR) were detected by qPCR, and their protein levels were analyzed by Western blot and immunofluorescence staining.
The formalin pain test induced emotional contagion behaviors in mice between the ECP and ECR levels. The VSDS procedure resulted in PTSD symptoms in mice; mice in the lowest quartile were characterized by high levels of anxiety, depression, and social avoidance behaviors, such as decreased autonomous activity and residence time in the open field test or open arms position and increased immobility time and social avoidance behavior. These were accompanied by reduced OTR and BDNF protein expression levels and fluorescence intensity, as well as reduced OTR and BDNF mRNA levels in the mPFC.
Emotional contagion can induce PTSD-like behavior in mice that witnessed stress. Low emotional contagion behavior increased PTSD susceptibility in the observer mice and might be related to the regulation of their oxytocin receptors.
创伤后应激障碍（PTSD）是一种严重的精神障碍，发生于个体目睹或经历重大创伤事件之后。情绪感染似乎在目睹创伤过程中发挥重要作用，凸显了理解心理或情绪应激的神经生物学后果及其对个体心理健康影响的重要性。因此，了解情绪感染与PTSD易感性之间的关系以及其背后异常的神经生物学和行为变化，有助于找到有效的分子治疗靶点。
采用福尔马林疼痛试验区分观察小鼠的情绪感染水平，根据其疼痛反应将它们分为四分位数。上四分位数和下四分位数分别为情绪感染易感性（ECP）组和抗性（ECR）组。当目睹应激时，采用替代性社会挫败应激（VSDS）程序在具有不同情绪感染水平的小鼠中建立PTSD模型。采用旷场试验、高架十字迷宫试验、社会互动试验和强迫游泳试验检测PTSD样症状。通过qPCR检测脑源性神经营养因子（BDNF）和催产素受体（OTR）在内侧前额叶皮质（mPFC）的mRNA表达变化，并通过蛋白质印迹法和免疫荧光染色分析其蛋白水平。
福尔马林疼痛试验在ECP和ECR水平的小鼠中诱导了情绪感染行为。VSDS程序导致小鼠出现PTSD症状；最低四分位数的小鼠表现出高水平的焦虑、抑郁和社会回避行为，如旷场试验中自主活动和停留时间减少，或高架十字迷宫试验中在开放臂位置的时间减少，以及不动时间和社会回避行为增加。这些行为伴随着mPFC中OTR和BDNF蛋白表达水平及荧光强度降低，以及OTR和BDNF mRNA水平降低。
情绪感染可在目睹应激的小鼠中诱导PTSD样行为。低情绪感染行为增加了观察小鼠的PTSD易感性，可能与其催产素受体的调节有关。
