Antidepressant potential of Mesembryanthemum cordifolium roots assisted by metabolomic analysis and virtual screening

Depression is a common mental disturbance that can be categorized as mild, moderate or severe. Mesemberine alkaloids, the main recognized phytoconstituents of some plants belonging to family Mesembryanthemaceae, are well-known as serotonin reuptake inhibitors. Therefore, the objective of this study is to evaluate the antidepressant activity of the alkaloidal fraction of Mesembryanthemum cordifolium L.f. (Aptenia cordifolia) roots, family Mesembryanthemaceae using forced swimming test, assisted by metabolomic analysis and in silico ligand-based and structure-based screening. Results showed that the alkaloidal fraction displayed an antidepressant activity superior to imipramine hydrochloride, a standard antidepressant agent. Nine alkaloids were annotated from the metabolomic analysis. Interestingly, among the dereplicated constituents, mesembrane (5) displayed strong binding affinity to SERT protein, which is slightly higher than the antidepressant drug venlafaxine. In conclusion, the alkaloidal fraction of the M. cordifolium (A. cordifolia) root exhibits an antidepressant activity which can be attributed in part to mesembrane (5).