Tauroursodeoxycholic Acid (TUDCA)-Lipid Interactions and Antioxidant Properties of TUDCA Studied in Model of Photoreceptor Membranes

• Published in: Membranes (Basel) Vol. 11; no. 5; p. 327
• Main Authors: Sabat, Michał J, Wiśniewska-Becker, Anna M, Markiewicz, Michał, Marzec, Katarzyna M, Dybas, Jakub, Furso, Justyna, Pabisz, Paweł, Duda, Mariusz, Pawlak, Anna M
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 29-04-2021; MDPI
• Subjects: antioxidant; Antioxidants; Bile; bile acids; Chemical compounds; Chinese medicine; Cholesterol; Electron paramagnetic resonance; Electron spin; Electron spin resonance; Fluidity; Glycerol; Herbal medicine; Lipid peroxidation; Lipids; liposome; Localization; Membranes; Mitochondria; Molecular dynamics; Neuroprotection; Nitrogen; Oxidation; Oxidation process; Oxygen consumption; Pharmacology; Phase transitions; photoreceptor membrane; Photoreceptors; Physical properties; Plasma membranes; Polarity; Signal transduction; Singlet oxygen; Spectroscopy; Taurine; Tauroursodeoxycholic acid; Traditional Chinese medicine; Ursodeoxycholic acid; Vision; United States > US; Germany; antioxidant; electron paramagnetic resonance; bile acids; photoreceptor membrane; lipid peroxidation; liposome
• ISSN: 2077-0375; 2077-0375
• DOI: 10.3390/membranes11050327

Tauroursodeoxycholic acid (TUDCA), a hydrophilic bile acid containing taurine conjugated with the ursodeoxycholic acid (UDCA), has been known and used from ancient times as a therapeutic compound in traditional Chinese medicine. TUDCA has recently been gaining significant interest as a neuroprotective agent, also exploited in the visual disorders. Among several mechanisms of TUDCA's protective action, its antioxidant activity and stabilizing effect on mitochondrial and plasma membranes are considered. In this work we investigated antioxidant activity of TUDCA and its impact on structural properties of model membranes of different composition using electron paramagnetic resonance spectroscopy and the spin labeling technique. Localization of TUDCA molecules in a pure POPC bilayer has been studied using a molecular dynamics simulation (MD). The obtained results indicate that TUDCA is not an efficient singlet oxygen (
O
(
Δ
)) quencher, and the determined rate constant of its interaction with
O
(
Δ
) is only 1.9 × 10
M
s
. However, in lipid oxidation process induced by a Fenton reaction, TUDCA reveals substantial antioxidant activity significantly decreasing the rate of oxygen consumption in the system studied. In addition, TUDCA induces slight, but noticeable changes in the polarity and fluidity of the investigated model membranes. The results of performed MD simulation correspond very well with the experimental results.