Orexin in depression: Evidence from basic and clinical research

Abstract

Orexin - a neuropeptide - is extensively distributed in the central nervous system and is involved in the regulation of diverse physiological functions and behaviors. Orexin is strongly associated with the onset and development of depression. The most important function of orexin is to interact with the transport system, mediating arousal, and energy homeostasis. Hypothalamic-ventral tegmental and hypothalamic-ventral thalamic pathways provide clues for understanding the function of orexin and related disorders, such as sleep disorders, eating disorders, and substance abuse. This article summarizes the basic and clinical studies on the role of the orexin system in regulating and treating depression, including the relationship between the expression level of orexin in specific brain areas and diseases, relationship between adolescent depression and orexin, orexin receptor antagonists as a treatment for depression, and narcolepsy, which is closely associated with depression. Research progress on the role of orexin in depression and recent relevant studies are summarized, providing novel directions for developing depression treatment strategies.

Keywords

Orexin / Depression / Sleep / Major depressive disorder / Neuron

Funding

This work was supported by the Key Scientific Research Program for Universities of Henan Province (no. 22A320029), the Key Science and Technology Program of Henan Province in China (no. 242102310274), the Medical Science and Technology Program of Henan Province (no. SBGJ202103096), the Program for Innovative Talents of Science and Technology in Henan Province (no. 23HASTIT043), and the Cultivation Project for Innovation Team in Teachers’ Teaching Proficiency by Zhengzhou Shu-Qing Medical College (No. 2024jxcxtd01).

Conflict of interest

The authors declare no conflicts of interest.

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