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The antioxidant effects of a polyphenol-rich grape pomace extract in vitro do not correspond in vivo using exercise as an oxidant stimulus.

Veskoukis AS, Kyparos A, Nikolaidis MG, Stagos D, Aligiannis N, Halabalaki M, Chronis K, Goutzourelas N, Skaltsounis L, Kouretas D - Oxid Med Cell Longev (2012)

Bottom Line: Numerous studies have examined the effects of plant extract administration on redox status at rest in animals and humans but their results are controversial.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.Our findings suggest that the grape pomace extract does not behave with the same way in vitro and in vivo.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.

ABSTRACT
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.

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Protective activity of the grape pomace extract on DNA strand scission induced by OH• and ROO•. (a) Extract antioxidant activity against OH•. Bluescript-SK+ plasmid DNA was exposed to UV plus H2O2 (lane 2) or to UV plus H2O2 in the presence of 100 μg/mL, 200 μg/mL, 400 μg/mL, 800 μg/mL and 1600 μg/mL of the extract, respectively (lanes 3–7) or to 1600 μg/mL of the extract alone (lane 8). (b) Extract antioxidant activity against ROO•. Bluescript-SK+ plasmid DNA was exposed to ROO• alone (lane 2) or to ROO• in the presence of 1 μg/mL, 2 μg/mL, 5 μg/mL, 10 μg/mL, 50 μg/mL and 100 μg/mL of the extract, respectively (lanes 3–8). Lane 1 represents Bluescript-SK+ plasmid DNA without any treatment. *Significantly different from the control value (P < 0.05). OC: open circular conformation of the plasmid, SC: supercoiled conformation of the plasmid.
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fig2: Protective activity of the grape pomace extract on DNA strand scission induced by OH• and ROO•. (a) Extract antioxidant activity against OH•. Bluescript-SK+ plasmid DNA was exposed to UV plus H2O2 (lane 2) or to UV plus H2O2 in the presence of 100 μg/mL, 200 μg/mL, 400 μg/mL, 800 μg/mL and 1600 μg/mL of the extract, respectively (lanes 3–7) or to 1600 μg/mL of the extract alone (lane 8). (b) Extract antioxidant activity against ROO•. Bluescript-SK+ plasmid DNA was exposed to ROO• alone (lane 2) or to ROO• in the presence of 1 μg/mL, 2 μg/mL, 5 μg/mL, 10 μg/mL, 50 μg/mL and 100 μg/mL of the extract, respectively (lanes 3–8). Lane 1 represents Bluescript-SK+ plasmid DNA without any treatment. *Significantly different from the control value (P < 0.05). OC: open circular conformation of the plasmid, SC: supercoiled conformation of the plasmid.

Mentions: The tested extract exhibited significant protective activity on DNA. Particularly, it inhibited DNA damage induced by ROO• and OH• radicals (Figure 2). The IC50 values for ROO• and OH• radicals are 1.5 and 500 mg/mL, respectively.


The antioxidant effects of a polyphenol-rich grape pomace extract in vitro do not correspond in vivo using exercise as an oxidant stimulus.

Veskoukis AS, Kyparos A, Nikolaidis MG, Stagos D, Aligiannis N, Halabalaki M, Chronis K, Goutzourelas N, Skaltsounis L, Kouretas D - Oxid Med Cell Longev (2012)

Protective activity of the grape pomace extract on DNA strand scission induced by OH• and ROO•. (a) Extract antioxidant activity against OH•. Bluescript-SK+ plasmid DNA was exposed to UV plus H2O2 (lane 2) or to UV plus H2O2 in the presence of 100 μg/mL, 200 μg/mL, 400 μg/mL, 800 μg/mL and 1600 μg/mL of the extract, respectively (lanes 3–7) or to 1600 μg/mL of the extract alone (lane 8). (b) Extract antioxidant activity against ROO•. Bluescript-SK+ plasmid DNA was exposed to ROO• alone (lane 2) or to ROO• in the presence of 1 μg/mL, 2 μg/mL, 5 μg/mL, 10 μg/mL, 50 μg/mL and 100 μg/mL of the extract, respectively (lanes 3–8). Lane 1 represents Bluescript-SK+ plasmid DNA without any treatment. *Significantly different from the control value (P < 0.05). OC: open circular conformation of the plasmid, SC: supercoiled conformation of the plasmid.
© Copyright Policy - open-access
Related In: Results  -  Collection

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fig2: Protective activity of the grape pomace extract on DNA strand scission induced by OH• and ROO•. (a) Extract antioxidant activity against OH•. Bluescript-SK+ plasmid DNA was exposed to UV plus H2O2 (lane 2) or to UV plus H2O2 in the presence of 100 μg/mL, 200 μg/mL, 400 μg/mL, 800 μg/mL and 1600 μg/mL of the extract, respectively (lanes 3–7) or to 1600 μg/mL of the extract alone (lane 8). (b) Extract antioxidant activity against ROO•. Bluescript-SK+ plasmid DNA was exposed to ROO• alone (lane 2) or to ROO• in the presence of 1 μg/mL, 2 μg/mL, 5 μg/mL, 10 μg/mL, 50 μg/mL and 100 μg/mL of the extract, respectively (lanes 3–8). Lane 1 represents Bluescript-SK+ plasmid DNA without any treatment. *Significantly different from the control value (P < 0.05). OC: open circular conformation of the plasmid, SC: supercoiled conformation of the plasmid.
Mentions: The tested extract exhibited significant protective activity on DNA. Particularly, it inhibited DNA damage induced by ROO• and OH• radicals (Figure 2). The IC50 values for ROO• and OH• radicals are 1.5 and 500 mg/mL, respectively.

Bottom Line: Numerous studies have examined the effects of plant extract administration on redox status at rest in animals and humans but their results are controversial.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.Our findings suggest that the grape pomace extract does not behave with the same way in vitro and in vivo.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.

ABSTRACT
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.

Show MeSH
Related in: MedlinePlus