MG-132, a potent proteasome and calpain inhibitor, boasts IC50s of 100 nM and 1.2 μM, respectively. This peptide aldehyde effectively halts the 26S proteasome complex's proteolytic activity. Beyond its inhibitory role, MG-132 activates autophagy and triggers apoptosis. Studies reveal that MG-132 can activate autophagy in vascular smooth muscle cells, inhibiting senescence through the PI3K/AKT/mTOR pathway. It also induces apoptosis in a cell cycle-dependent manner, highlighting its multifaceted bioactivity in cellular regulation.