Mitochondria – indirect, ROS-mediated disruption

Mitochondria – indirect, ROS-mediated disruption is a pharmacological mechanism of action rather than a specific molecular target like a protein or receptor. This process involves the induction of intracellular reactive oxygen species (ROS) which subsequently cause oxidative damage to mitochondrial membranes and associated proteins (Gorrini et al., 2013). Such oxidative stress leads to the loss of mitochondrial membrane potential and the opening of the mitochondrial permeability transition pore (MPTP), resulting in the release of pro-apoptotic factors like cytochrome c into the cytoplasm (Orrenius, 2007). This mechanism is frequently exploited in cancer therapy because malignant cells often exhibit higher baseline ROS levels and altered antioxidant capacities, making them more vulnerable to further ROS increases than healthy cells (Pelicano et al., 2004). Drugs such as arsenic trioxide and certain anthracyclines utilize this pathway to trigger apoptosis in recalcitrant tumors. However, because this mechanism is not specific to a single protein, it can lead to significant off-target effects, most notably cardiotoxicity, due to the high mitochondrial density and limited antioxidant capacity of cardiac myocytes (Octavia et al., 2012).

Other names

Mitochondrial ROS inductionIndirect mitochondrial disruptionROS-mediated apoptosisOxidative stress-induced mitochondrial dysfunction

Induction of reactive oxygen species (ROS), inhibition of antioxidant enzymes (e.g., glutathione peroxidase), disruption of mitochondrial membrane potential (ΔΨm), and activation of the intrinsic apoptotic pathway via cytochrome c release.