Supplementary Material for: Fluoxetine Treatment Rescues Energy Metabolism Pathway Alterations in a Posttraumatic Stress Disorder Mouse Model

<br>Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder. Several studies have attempted to characterize molecular alterations associated with PTSD, but most findings were limited to the investigation of specific cellular markers in the periphery or defined brain regions. In the current study, we aimed to unravel affected molecular pathways/mechanisms in the fear circuitry associated with PTSD. We interrogated a foot shock-induced PTSD mouse model by integrating proteomics and metabolomics profiling data. Alterations at the proteome level were analyzed using in vivo ¹⁵N metabolic labeling combined with mass spectrometry in the prelimbic cortex (PrL), anterior cingulate cortex (ACC), basolateral amygdala, central nucleus of the amygdala and CA1 of the hippocampus between shocked and nonshocked (control) mice, with and without fluoxetine treatment. In silico pathway analyses revealed an upregulation of the citric acid cycle pathway in PrL, and downregulation in ACC and nucleus accumbens (NAc). Chronic fluoxetine treatment prevented decreased citric acid cycle activity in NAc and ACC and ameliorated conditioned fear response in shocked mice. Our results shed light on the role of energy metabolism in PTSD pathogenesis and suggest potential therapy through mitochondrial targeting.

创伤后应激障碍（Posttraumatic stress disorder, PTSD）是一种高发的精神疾病。既往多项研究试图解析与PTSD相关的分子改变，但多数研究结果仅局限于对外周或特定脑区的特异性细胞标志物开展探究。本研究旨在阐明与PTSD相关的恐惧环路中受累的分子通路与机制。我们通过整合蛋白质组学（proteomics）与代谢组学（metabolomics）分析数据，对足部电击诱导的PTSD小鼠模型进行了系统研究。在接受氟西汀处理与未处理的电击组及对照组小鼠中，我们采用体内¹⁵N代谢标记结合质谱（mass spectrometry）技术，对前边缘皮层（prelimbic cortex, PrL）、前扣带回皮层（anterior cingulate cortex, ACC）、基底外侧杏仁核、杏仁中央核以及海马CA1区的蛋白质组变化进行了分析。生物信息学通路分析显示，前边缘皮层内的三羧酸循环通路呈现上调，而前扣带回皮层与伏隔核（nucleus accumbens, NAc）中该通路则发生下调。长期氟西汀给药可阻断伏隔核与前扣带回皮层内三羧酸循环活性的降低，并改善电击小鼠的条件性恐惧反应。本研究结果揭示了能量代谢在PTSD发病机制中的重要作用，并提示靶向线粒体有望成为PTSD的潜在治疗策略。