Similarly, increased caspase-3 and -7 activity was observed in the hippocampus of rats subjected to the depression model.32, 33, 34 While caspase activity has not been directly reported in MDD patients, a previous study revealed an association between the upregulation of 20 genes linked to the apoptosis pathway in MDD patients.35 Here, CASP3 is linked to depressive symptom measurement.