Abstract: Objective · To discuss the effects of citalopram on miRNA-16/serotonin transporter (SERT) pathway in peripheral blood of the patients with depression. Methods · Forty-five patients with depression without medication (untreated group), 32 patients with depression treated with medicine(drug treated group) and 32 healthy people (control group) were enrolled in the study. Hamilton Depression Scale-17 items were used to evaluate the depressive symptoms. The expression level of plasma miRNA-16 was detected by fluorescence quantitative PCR, and the level of SERT protein in platelets was detected by Western blotting. Fourteen of the baseline patients who were treated with citalopram were followed up for 2 months. After the follow-up, the evaluation of HAMD-17, the detection of miRNA-16 and SERT protein were conducted. Results · There was no significant difference in the expression level of plasma miRNA-16 among the three groups (F=0.421, P=0.657). There was no significant difference of SERT protein expression in the platelets among the three groups (F=0.112, P=0.894). The follow-up study showed that the HAMD-17 score decreased after 2 months (Z=?3.187, P=0.001), the average expression level of plasma miRNA-16 increased (t=2.455, P=0.032), and the expression of SERT protein in the platelets did not change (t=?0.750, P=0.470) in 14 patients who were treated with citalopram. Conclusion · Citalopram, a serotonin reuptake inhibitor, can down-regulate the expression of plasma miRNA-16 in patients with depression, and the decrease of the platelet serotonin is not caused by the decrease of SERT protein on platelet membrane, but may be related to the decrease of the SERT function.

Key words: citalopram, depression, serotonin transporter (SERT), miRNA-16