Intracellular ROS protection efficiency and free radical-scavenging activity of curcumin.
Curcumin has many pharmaceutical applications, many of which arise from its potent antioxidant properties. The present research examined the antioxidant activities of curcumin in polar solvents by a comparative study using ESR, reduction of ferric iron in aqueous medium and intracellular ROS/toxicity assays. ESR data indicated that the steric hindrance among adjacent big size groups within a galvinoxyl molecule limited the curcumin to scavenge galvinoxyl radicals effectively, while curcumin showed a powerful capacity for scavenging intracellular smaller oxidative molecules such as H₂O₂, HO•, ROO•. Cell viability and ROS assays demonstrated that curcumin was able to penetrate into the polar medium inside the cells and to protect them against the highly toxic and lethal effects of cumene hydroperoxide. Curcumin also showed good electron-transfer capability, with greater activity than trolox in aqueous solution. Curcumin can readily transfer electron or easily donate H-atom from two phenolic sites to scavenge free radicals. The excellent electron transfer capability of curcumin is because of its unique structure and different functional groups, including a β-diketone and several π electrons that have the capacity to conjugate between two phenyl rings. Therfore, since curcumin is inherently a lipophilic compound, because of its superb intracellular ROS scavenging activity, it can be used as an effective antioxidant for ROS protection within the polar cytoplasm.
Research Institute for Fundamental Sciences (RIFS), University of Tabriz, Tabriz, Iran. barzegar@tabrizu.ac.ir
Abolfazl
A
Barzegar
Ali A
AA
Moosavi-Movahedi
D000818:Animals; D001559:Benzhydryl Compounds / Q000378:metabolism; D002460:Cell Line; D003474:Curcumin / Q000378:metabolism / Q000494:pharmacology*; D019610:Cytoprotection / Q000187:drug effects; D004578:Electron Spin Resonance Spectroscopy; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism / Q000494:pharmacology*; D042541:Intracellular Space / Q000187:drug effects* / Q000378:metabolism*; D032446:Myoblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*
D001559:Benzhydryl Compounds; D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D003474:Curcumin; C020338:galvinoxyl