Xinling Zhao,1,2,* Huijin Jie,3,* Jun Wang,1 Yu Liu,4 Yilin Liu,2 Fuyi Qin,2 Qing Long,2 Xi Hou,5 Xin-Wen Zhang,6 Wenzhi Wu,7 Xiaoqin Wu,2 Jing Li,8 Yong Zeng2 

1Department of Clinical Psychology, People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, People’s Republic of China; 2Department of Psychiatry, the Second Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China; 3Haining Fourth People’s Hospital, Haining, People’s Republic of China; 4Department of Psychiatry, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China; 5Department of Clinical Psychology, The Sixth Affiliated Hospital of Kunming Medical University, Yuxi, People’s Republic of China; 6Department of Psychiatry, Hong He Second People’s Hospital, Jian Shui, People’s Republic of China; 7Faculty of psychology, Beijing Normal University, Beijing, People’s Republic of China; 8Sichuan Provincial Center for Mental Health, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Jing Li; Yong Zeng, Email lijingjingjing222@163.com; zengyong@kmmu.edu.cn

Background: Adolescents with major depressive (MDD) episodes associated with childhood trauma have a poorer response to treatment and a higher risk of suicide. The underlying etiology is unclear. Brain-derived neurotrophic factor (BDNF) could improve depressive symptoms by down-regulating mammalian target of rapamycin (mTOR) signaling pathways, which was involved in adverse environmental stimuli during neurodevelopment. BDNF and mTOR have not been reported simultaneously in adolescents with major depressive episodes associated with childhood trauma.
Methods: Childhood Trauma Questionnaire-Short Form (CTQ-SF), Children’s Depression Inventory (CDI) and Children’s Depression Rating Scale-Revised (CDRS-R) were used to evaluate the recruited adolescents with major depression episodes. Serum BDNF and p-mTOR levels were measured by ELISA in 31 adolescents with major depression episodes with childhood trauma and 18 matched healthy control.
Results: The serum levels of BDNF were significantly lower (p< 0.001); and the serum levels of p-mTOR were high (p=0.003) in the adolescents with the first episode of major depressive episode accompanied by childhood trauma. Of the 31 adolescents with major depressive episodes, 17 had suicide or self-injury. Compared with the healthy control group, the serum levels of BDNF in patients with suicide or self-injury were lower than those without suicide or self-injury(p< 0.001); the serum levels of p-mTOR were higher than those without suicide or self-injury (p=0.01). While in patients without suicide or self-injury, only serum p-mTOR was significantly higher than that in healthy group (p=0.028). BDNF was negatively correlated with CDRS-R (r=− 0.427, p=0.006), p-mTOR was positively correlated with CDI (r=0.364, p=0.048). According to Receiver Operating Characteristic Curve (ROC), the combination of serum BDNF and p-mTOR levels have better diagnostic value.
Conclusion: Neurotrophic and signaling pathways, involving BDNF and p-mTOR, may play a role in adolescent MDD with a history of childhood trauma, especially patients with suicide and self-injury tendencies.

Keywords: brain-derived neurotrophic factor, p-mTOR, major depressive disorder, suicide, adolescent, childhood trauma