Alpha-tocopheryl quinone and Ubiquinone (Oxidized Vitamin E and Oxidized Coenzyme Q10) (TQ/CoQ10)

Oxidized vitamin E (alpha-tocopheryl quinone) and oxidized CoQ10 (ubiquinone) are the oxidized forms of two critical lipophilic antioxidants that function in a synergistic redox network to protect cell membranes (Life Extension, 2024). In this system, vitamin E scavenges lipid peroxyl radicals and is subsequently regenerated by the reduced form of CoQ10, ubiquinol (Rthm, 2026). This recycling process is a vital defense against lipid peroxidation and ferroptosis, an iron-dependent form of regulated cell death (Zheng et al., 2024). While these molecules are metabolites rather than protein targets, the enzymes that maintain their reduced states, such as Ferroptosis Suppressor Protein 1 (FSP1) and NQO1, are significant therapeutic targets in oncology and neurodegeneration (Zheng et al., 2024). Drugs targeting this system include antioxidant supplements like alpha-tocopherol and ubiquinol, as well as synthetic analogs like idebenone and MitoQ (Rthm, 2026). In cancer therapy, inhibitors of recycling enzymes like FSP1 are being investigated to induce ferroptosis in tumor cells (Zheng et al., 2024). Monitoring the levels of these oxidized species serves as a biomarker for oxidative stress and mitochondrial dysfunction in various diseases (ResearchGate, 2025).

Other names

Alpha-tocopheryl quinoneUbiquinoneVitamin E quinoneCoenzyme Q10 (oxidized)Alpha-tocopheryl radicalOxidized alpha-tocopherol

Therapeutic strategies involve either replenishing the reduced antioxidant pool (ubiquinol and tocopherol) to prevent oxidative damage or inhibiting recycling enzymes like FSP1 to promote ferroptotic cell death in cancer cells.