Title:	Impact of antioxidants on cardiolipin oxidation in liposomes: Why mitochondrial cardiolipin serves as an apoptotic signal
Authors:	Lokhmatikov, Alexey V. Voskoboynikova, Natalia Cherepanov, Dimitry A. Skulachev, Maxim V. Steinhoff, Heinz-Jürgen Skulachev, Vladimir P. Mulkidjanian, Armen P.
Abstract:	Molecules of mitochondrial cardiolipin (CL) get selectively oxidized upon oxidative stress, which triggers the intrinsic apoptotic pathway. In a chemical model most closely resembling the mitochondrial membrane—liposomes of pure bovine heart CL—we compared ubiquinol-10, ubiquinol-6, and alpha-tocopherol, the most widespread naturally occurring antioxidants, with man-made, quinol-based amphiphilic antioxidants. Lipid peroxidation was induced by addition of an azo initiator in the absence and presence of diverse antioxidants, respectively. The kinetics of CL oxidation was monitored via formation of conjugated dienes at 234 nm. We found that natural ubiquinols and ubiquinol-based amphiphilic antioxidants were equally efficient in protecting CL liposomes from peroxidation; the chromanol-based antioxidants, including alpha-tocopherol, were 2-3 times less efficient. Amphiphilic antioxidants, but not natural ubiquinols and alpha-tocopherol, were able, additionally, to protect the CL bilayer from oxidation by acting from the water phase. We suggest that the previously reported therapeutic efficiency of mitochondrially targeted amphiphilic antioxidants is owing to their ability to protect those CL molecules that are inaccessible to natural hydrophobic antioxidants, being trapped within respiratory supercomplexes. The high susceptibility of such occluded CL molecules to oxidation may have prompted their recruitment as apoptotic signaling molecules by nature.
Citations:	Oxidative Medicine and Cellular Longevity Volume 2016 (2016), Kairo: Hindawi
URL:	https://osnadocs.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2016062014540
Subject Keywords:	Mitochondrial Cardiolipin; Cardiolipin Oxidation; Liposome; Apoptotic Signal
Issue Date:	20-Jun-2016
License name:	Namensnennung 4.0 International
License url:	http://creativecommons.org/licenses/by/4.0/
Type of publication:	Einzelbeitrag in einer wissenschaftlichen Zeitschrift [article]
Appears in Collections:	FB06 - Hochschulschriften Open-Access-Publikationsfonds

This item is licensed under a Creative Commons License