title: Single dose administration of L-carnitine improves antioxidant activities in healthy subjects.
abstract: 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 (C(max)) and area under the curve (AUC(0-∞)) 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 C(max) 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.
authors.affiliation: Department of Pharmacy, the Affiliated Hospital of Medical College, Qingdao University, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Cao
authors.forename: Hai-Jun
authors.initials: HJ
authors.lastname: Qu
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Chun-Bo
authors.initials: CB
authors.lastname: Wang
authors.forename: Le-Xin
authors.initials: LX
authors.lastname: Wang
authors.forename: Zhi-Wu
authors.initials: ZW
authors.lastname: Han
mesh_terms: D000284:Administration, Oral; D000975:Antioxidants / Q000378:metabolism*; D002331:Carnitine / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005979:Glutathione Peroxidase / Q000378:metabolism; D006262:Health; D006801:Humans; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
chemical_list: D000975:Antioxidants; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D002331:Carnitine