Development of MAO-A and 5-HT2AR Dual Inhibitors with Improved Antidepressant Activity

Designing dual-target inhibitors targeting 5-HT_2AR and MAO-A could synergistically promote interstitial 5-HT levels, so as to exhibit a more efficient antidepressant effect. On the premise of maintaining the original pharmacophore binding, arylpiperazine scaffolds and 5-oxygen-substituted oxoisoaporphines were hybridized to afford 15 dual-target inhibitors through suitable linkers. Among all inhibitors, I₁₄ exhibited the best inhibitory activities against 5-HT_2AR and MAO-A. In vitro cell proliferation assays showed that most compounds were nontoxic to neuronal cells and normal hepatocytes. I₁₄ also significantly ameliorated the depression-like behavior of zebrafish and mice. Further study revealed that I₁₄ was able to occupy the active cavity of 5-HT_2AR and MAO-A with multiple hydrogen bonding forces and π-π stacking interaction. I₁₄ was also able to repair the damage of mice hippocampal neuronal cells and reduce the expression of 5-HT_2AR in mice brain tissue. In conclusion, I₁₄ could be a potential antidepressant candidate for further study.