Single Dose Administration of L-Carnitine Improves Antioxidant Activities in Healthy Subjects

• Published in: The Tohoku Journal of Experimental Medicine Vol. 224; no. 3; pp. 209 - 213
• Main Authors: Qu, Hai-jun, Han, Zhi-wu, Li, Ping, Wang, Le-xin, Wang, Chun-bo, Cao, Yu
• Format: Journal Article
• Language: English
• Published: Japan Tohoku University Medical Press 2011
• Subjects: Administration, Oral; Antioxidants - metabolism; Carnitine - administration & dosage; Carnitine - blood; Carnitine - pharmacokinetics; Carnitine - pharmacology; catalase; Catalase - metabolism; Dose-Response Relationship, Drug; glutathione peroxidase; Glutathione Peroxidase - metabolism; Health; Humans; L-carnitine; superoxide dismutase; Superoxide Dismutase - metabolism; Time Factors; total antioxidative capacity
• ISSN: 0040-8727; 1349-3329; 1349-3329
• DOI: 10.1620/tjem.224.209

L-carnitine has been used as a supplement to treat cardiovascular or liver disease. However, there has been little information about the effect of L-carnitine on anti-oxidation capability in healthy human subjects. This study was designed to investigate the correlation between plasma L-carnitine concentration and antioxidant activity. Liquid L-carnitine (2.0 g) was administered orally as a single dose in 12 healthy subjects. Plasma concentration of L-carnitine was detected by HPLC. The baseline concentration of L-carnitine was 39.14 ± 5.65 μmol/L. After single oral administration, the maximum plasma concentration (Cmax) and area under the curve (AUC0-∞) were 84.7 ± 25.2 μmol/L and 2,676.4 ± 708.3 μmol/L·h, respectively. The half-life and the time required to reach the Cmax was 60.3 ± 15.0 min and 3.4 ± 0.46 h, respectively. There was a gradual increase in plasma concentrations of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase and total antioxidative capacity (T-AOC) in the first 3.5 h following L-carnitine administration. The plasma concentrations of SOD, GSH-Px, catalase and T-AOC returned to baseline levels within 24 h. A positive correlation was found between L-carnitine concentration and the antioxidant index of SOD (r = 0.992, P < 0.01), GSH-Px (r = 0.932, P < 0.01), catalase (r = 0.972, P < 0.01) or T-AOC (r = 0.934, P < 0.01). In conclusion, L-carnitine increases activities of antioxidant enzymes and the total antioxidant capacity in healthy subjects. It may be useful as a supplementary therapy for chronic illnesses involving excessive oxidative stress.