Reactive oxygen species and mitochondrial oxidative stress system (ROS/mOSS)

The Reactive Oxygen Species (ROS) and mitochondrial oxidative stress system refers to the complex network of biochemical processes involved in the generation, regulation, and neutralization of oxygen-derived free radicals within the mitochondria. Mitochondria are the primary source of cellular ROS, mainly produced as byproducts of the electron transport chain during oxidative phosphorylation (Murphy, 2009, PMID: 19284141). While physiological levels of ROS are vital for intracellular signaling and homeostatic regulation, an imbalance between ROS production and antioxidant defense mechanisms leads to oxidative stress, causing damage to mitochondrial DNA, proteins, and membrane lipids (Sies et al., 2017, PMID: 28235676). This dysfunction is a hallmark of numerous pathologies, including neurodegenerative diseases like Parkinson's and Alzheimer's, cardiovascular diseases, and the aging process itself (Barnham et al., 2004, PMID: 15111908). Pharmacological interventions targeting this system include mitochondrial-targeted antioxidants like MitoQ and elamipretide, which aim to reduce oxidative damage without disrupting essential signaling (Smith et al., 2012, PMID: 22313311). However, the therapeutic application is challenged by the need for precise redox modulation, as excessive suppression of ROS can interfere with necessary cellular functions (Gutteridge & Halliwell, 2018, PMID: 29360521).

Other names

Mitochondrial redox systemMitochondrial ROS production pathwayOxidative phosphorylation-linked ROSMitochondrial antioxidant defense system

Drugs targeting this system typically act through the direct scavenging of free radicals, the modulation of mitochondrial electron transport chain complexes to reduce electron leakage, or the induction of endogenous antioxidant enzymes via the Nrf2/ARE signaling pathway (Sies et al., 2017, PMID: 28235676; Smith et al., 2012, PMID: 22313311).