In vivo antioxidative activity of a quantified Pueraria lobata root extract.
OBJECTIVE
Oxidative stress has been associated with many pathological disorders such as atherosclerosis, diabetes and cancer. Supplementation with exogenous antioxidants, including phenolic compounds from plant sources, may help to restore the pro-oxidative/antioxidative balance. To take into account effects of absorption, metabolisation, plasma protein binding, distribution, and elimination, antioxidative research should not be limited to in vitro assays but be extended to in vivo models.


METHODS
In the present work a quantified 50% EtOH root extract of Pueraria lobata (Willd.) Ohwi (Fabaceae) was selected to determine its in vivo antioxidative activity in a diabetic rat model, where diabetes and the accompanying oxidative stress were induced by intraperitoneal administration of streptozotocin. This root extract was found to contain 10.42+/-0.15% puerarin as the main constituent and smaller amounts of the related isoflavonoids 3'-hydroxypuerarin, 3'-methoxypuerarin, 6''-xylosylpuerarin, daidzin, genistin, daidzein and genistein, as determined by a validated HPLC method. This extract was administered orally at a daily dose of 500 mg/kg root extract, corresponding to 50mg/kg puerarin, during 3 weeks. In addition the effect on the plasma concentration of some fat-soluble antioxidants (co-enzyme Q(9), alpha- and gamma-tocopherol) was evaluated.


CONCLUSIONS
The level of malondialdehyde (MDA) in plasma, used as a marker of oxidative damage to lipids, was reduced to the same level as in healthy control animals, and as in the positive control group treated daily with 50mg/kg alpha-tocopherol acetate. No obvious signs of toxicity were observed by administration of 10x the treatment dose.
Laboratory of Pharmacognosy and Pharmaceutical Analysis, Department of Pharmaceutical Sciences, Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
Lidiya
L
Bebrevska
Kenne
K
Foubert
Nina
N
Hermans
Shyama
S
Chatterjee
Eric
E
Van Marck
Guido
G
De Meyer
Arnold
A
Vlietinck
Luc
L
Pieters
Sandra
S
Apers
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology* / Q000633:toxicity; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000139:chemically induced; D004365:Drugs, Chinese Herbal / Q000494:pharmacology / Q000633:toxicity; D007529:Isoflavones / Q000032:analysis / Q000494:pharmacology / Q000633:toxicity; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D018384:Oxidative Stress / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology* / Q000633:toxicity; D018517:Plant Roots / Q000737:chemistry*; D029908:Pueraria / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D014451:Ubiquinone / Q000097:blood; D024502:alpha-Tocopherol / Q000008:administration & dosage / Q000097:blood; D024504:gamma-Tocopherol / Q000097:blood
D000975:Antioxidants; D001786:Blood Glucose; D004365:Drugs, Chinese Herbal; D007529:Isoflavones; D010936:Plant Extracts; D014451:Ubiquinone; D008315:Malondialdehyde; D024504:gamma-Tocopherol; D024502:alpha-Tocopherol; C030571:ubiquinone 9; C033607:puerarin