The antioxidant effects of a polyphenol-rich grape pomace extract in vitro do not correspond in vivo using exercise as an oxidant stimulus.
Fruits, such as grapes, are essential food of the Mediterranean diet. Grape extracts have potent antioxidant and chemopreventive properties in vitro. Numerous studies have examined the effects of plant extract administration on redox status at rest in animals and humans but their results are controversial. However, there are no studies comparing the in vitro and in vivo effects of plant extracts on oxidative stress using exercise as an oxidant stimulus. Thus, the aim of this study was to investigate whether a polyphenol-rich grape pomace extract of the Vitis vinifera species possesses in vitro antioxidant properties and to examine whether these properties apply in an in vivo model at rest and during exercise. Our findings indicate that the tested extract exhibits potent in vitro antioxidant properties because it scavenges the DPPH(•) and ABTS(•+) radicals and inhibits DNA damage induced by peroxyl and hydroxyl radicals. Administration of the extract in rats generally induced oxidative stress at rest and after exercise whereas exercise performance was not affected. Our findings suggest that the grape pomace extract does not behave with the same way in vitro and in vivo.
Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
Aristidis S
AS
Veskoukis
Antonios
A
Kyparos
Michalis G
MG
Nikolaidis
Dimitrios
D
Stagos
Nektarios
N
Aligiannis
Maria
M
Halabalaki
Konstantinos
K
Chronis
Nikolaos
N
Goutzourelas
Leandros
L
Skaltsounis
Dimitrios
D
Kouretas
D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D004249:DNA Damage / Q000187:drug effects; D004912:Erythrocytes / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D017665:Hydroxyl Radical / Q000633:toxicity; D008297:Male; D016877:Oxidants / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects; D010545:Peroxides / Q000633:toxicity; D010805:Physical Conditioning, Animal; D010936:Plant Extracts / Q000494:pharmacology*; D059808:Polyphenols / Q000737:chemistry / Q000494:pharmacology*; D050050:Protein Carbonylation; D051381:Rats; D017208:Rats, Wistar; D027843:Vitis / Q000737:chemistry*
D000975:Antioxidants; D016877:Oxidants; D010545:Peroxides; D010936:Plant Extracts; D059808:Polyphenols; C049375:perhydroxyl radical; D017665:Hydroxyl Radical; D002374:Catalase; D005978:Glutathione