Recent advance in autophagy-related pathways and key biomarkers in major depressive disorder

Abstract

Major depressive disorder (MDD) is a very common and severe mental disorder. Persistent emotional distress is one of its main clinical symptoms. The etiology of MDD is complex and highly heterogeneous, and has not yet been clarified. Antidepressant is a kind of important method for the treatment of MDD. However, there are still some problems such as slow onset of effect, low cure rate, safety to be further improved, and low compliance, which also reflect people's lack of understanding of the pathogenesis of MDD. Autophagy is a mechanism of cell degradation, which plays an important role in maintaining the stabilization of homeostasis. Mammalian target of rapamycin (mTOR) is an important regulator of autophagy, and adverse conditions can activate autophagy through mTOR-dependent or mTOR-independent autophagy pathways. Microtubule-associated protein light chain 3-Ⅱ (LC3-Ⅱ), Bcl-2 interacting coiled-coil protein 1 (Beclin-1) and p62 are common to be used in the measurement of autophagy flux. In recent years, more and more studies have shown that impaired autophagy may be involved in the development of MDD and antidepressant treatment may affect autophagy. Therefore, regulating impaired autophagy pathways may be a promising target of antidepressant treatment. In the future, more attention should be paid to the study of autophagy signaling pathway in the central nervous system to provide more reliable evidence for the mechanism of MDD and antidepressant treatment. This article introduces the roles of common mTOR-dependent autophagy pathways, mTOR-independent autophagy pathways and autophagic markers in the progression and treatment of MDD.

Keywords

• major depressive disorder (mdd)
• autophagy
• autophagy-related pathway
• autophagic biomarker