coenzyme-q10 has been researched along with dihydrolipoic-acid* in 2 studies
2 other study(ies) available for coenzyme-q10 and dihydrolipoic-acid
| Article | Year |
|---|---|
Coenzyme Q10, vitamin E, and dihydrothioctic acid cooperatively prevent diene conjugation in isolated low-density lipoprotein.
Coenzyme Q (Q10) and alpha-tocopherol cooperatively delay the onset of diene conjugation in isolated human low density lipoprotein if supplied in water-soluble preparations to blood serum. Both copper ions and morpholino sydnonimine (in the presence of glucose; SIN-1-glucose) -driven diene conjugation is measurable as soon as both reduced Q10 and tocopherol are oxidized, where tocopherol oxidation starts after 80-90% consumption of reduced Q10. LDL-bound Q10 in turn can be rapidly reduced by dihydrolipoic acid (thioctic acid). This reaction is at least 10 times faster than reduction by ascorbic acid. Topics: Antioxidants; Ascorbic Acid; Coenzymes; Copper; Humans; Ions; Lipoproteins, LDL; Male; Middle Aged; Models, Biological; Molsidomine; Nitric Oxide Donors; Oxygen; Protein Binding; Thioctic Acid; Time Factors; Ubiquinone; Vitamin E | 2000 |
Dihydrolipoic acid maintains ubiquinone in the antioxidant active form by two-electron reduction of ubiquinone and one-electron reduction of ubisemiquinone.
Dihydrolipoic acid (DHLA) is a constituent of cellular energy metabolism, where it cycles between the oxidized and reduced form. The two thiol residues of DHLA make this biomolecule susceptible to most radical species and prevent Fenton-type reactions by chelating free iron. In this study we present a novel mode of action by which DHLA exerts antioxidant function in combination with coenzyme Q (ubiquinone). DHLA was found to reduce ubiquinone to ubiquinol by the transfer of a pair of electrons, thereby increasing the antioxidant capacity of coenzyme Q in biomembranes. In addition, ubisemiquinone, which was earlier shown to be an active oxygen radical source when existing in the anionic form, is removed from equilibrium by the addition of a single electron from DHLA. The high reactivity of DHLA with this potentially deleterious ubisemiquinone species not only prevents the formation of prooxidants, it also keeps ubiquinone in its antioxidant active form. Experimental data of this study demonstrate a superadditive effect of ubiquinone in combination with DHLA in preventing peroxidation of biomembranes. Topics: Animals; Antioxidants; Coenzymes; Cold Temperature; Cytoprotection; Electron Spin Resonance Spectroscopy; Electrons; Hydrogen-Ion Concentration; Mitochondria, Liver; Oxidation-Reduction; Rats; Spectrophotometry, Ultraviolet; Spectrum Analysis; Thioctic Acid; Ubiquinone | 1999 |