BACKGROUND: Major depressive disorder (MDD) is a chronic, life-threatening, highly disabling disease. Standardized treatment with fewer adverse effects, quick onset, and long-term maintenance of the effects of brief treatment for MDD is always being pursued. Long non-coding RNAs (lncRNAs) are highly expressed in the central nervous system and are involved in the occurrence and development of neurodegenerative and psychiatric diseases. This study aimed to investigate whether the overexpression and interference of 3 differentially down-regulated lncRNAs (NONHSAT142707, NONHSAG045500, and ENST00000517573) in MDD can affect the expression of central neurotransmitter serotonin (5-hydroxytryptamine) transporter (SERT) in vitro.

MATERIAL AND METHODS: First, we synthesized and validated the effect of 3 lncRNA plasmids and small interfering RNAs (siRNAs); next, we transfected the plasmids and siRNAs that caused significant overexpression or interference in SK-N-SH cells, and tested the expression of SERT by qRT-PCR.

RESULTS: The results showed that 3 lncRNA plasmids and siRNAs2 caused overexpression and interference, respectively. Only the overexpression of NONHSAG045500 could significantly inhibit the expression of SERT; interference with NONHSAG045500 could significantly strengthen the expression of SERT.

CONCLUSIONS: This study indicated that the expression of SERT could be regulated by up-regulating or down-regulating NONHSAG045500 expression and suggested that NONHSAG045500 could potentially be established as a new therapeutic target of MDD. Future work may be needed to definitively determine the correlation between NONHSAG045500 and SERT in vivo.

Keywords: Depressive Disorder, Major, Serotonin Plasma Membrane Transport Proteins