CASP9 and malnutrition: In this study, malnutrition-induced oxidative stress could be due to cytochrome binding to apoptotic protease-activating factor-1 (APAF-1) released from the mitochondria; then procaspase-9 can activate caspase-9.44 Caspase-9, which serves as an apoptosis initiator, is dimerized, which triggers feedback by inhibiting BCL-2 release and then binds to procaspase-3 to activate caspase-3.