SIRT1 and major depressive disorder: With the aim to screen for a SIRT1-targeting miRNA associated with MDD, we compared the expression of eight candidate miRNAs, including hsa-miR-30e, hsa-miR-132, hsa-miR-135b, hsa-miR-155b, hsa-miR-181b, hsa-miR-199b, hsa-miR-448 and hsa-miR-543, in the blood samples of healthy and MDD patients.