Title: Antioxidant capacity and stability of liposomes containing a triglyceride derivative of lipoic acid Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 29, 2012
Publication Date: March 29, 2012
Citation: Laszlo, J.A., Evans, K.O., Compton, D.L., Appell, M.D. 2012. Antioxidant capacity and stability of liposomes containing a triglyceride derivative of lipoic acid [abstract]. American Chemical Society. PAPER ID: 10084 Technical Abstract: The multi-functional nutritional agent lipoic acid offers numerous beneficial effects to oxidatively stressed tissues. Lipoic acid was enzymatically incorporated into a triglyceride in conjunction with oleic acid, creating lipoyl dioleoylglycerol, and then chemically reduced to form dihydrolipoyl dioleoylglycerol. These two triglyceride forms of lipoic acid stabilized phospholipid vesicles. Stabilization resulted from increased packing density of phospholipid acyl chains. Scavenging activity against AAPH radical was monitored. Dihydrolipoyl dioleoylglycerol in liposomes demonstrated strong antioxidant capacity in comparison to the conventional Trolox standard. Fluorescence quenching measurements indicated the lipoyl moiety of the triglycerides is positioned near the membrane’s hydrophilic/hydrophobic boundary. Molecular modeling of lipoyl dioleoylglycerol and dihydrolipoyl dioleoylglycerol in a phospholipid layer confirmed the existence of an extended configuration for the molecules that accounts for the interfacial location of the lipoyl moiety, which may allow the antioxidant to readily react with adsorbing radical species.