title: Polyphenolic composition of grape stem extracts affects antioxidant activity in endothelial and muscle cells.
abstract: The aim of the present study was the assessment of the antioxidant effects of polyphenolic extracts derived from the stems of three Greek grape varieties (Moshomayro, Mavrotragano and Mandilaria) in endothelial (EA.hy926) and muscle (C2C12) cells. We also investigated the effects of the polyphenolic composition on the antioxidant effects of the grape stem extracts. For this purpose, the endothelial and muscle cells were treated with low non-cytotoxic concentrations of the extracts for 24 h in order to assess the effects of the extracts on cellular redox status using oxidative stress biomarkers. The oxidative stress markers were thiobarbituric acid reactive substances (TBARS), protein carbonyl (CARB) levels, reactive oxygen species (ROS) levels and glutathione (GSH) levels. The results revealed that treatment of the EA.hy926 cells with Mandilaria extract significantly decreased the TBARS levels by 14.8% and the CARB levels by 25.9 %, while it increased the GSH levels by 15.8% compared to the controls. Moreover, treatment of the EA.hy926 cells with Mavrotragano extract significantly increased the GSH levels by 20.2%, while it significantly decreased the TBARS and CARB levels by 12.5% and 16.6%, respectively. Treatment of the C2C12 cells with Mandilaria extract significantly decreased the TBARS levels by 47.3 %, the CARB levels by 39.0 % and the ROS levels by 21.8%, while it increased the GSH levels by 22.6% compared to the controls. Moreover, treatment of the C2C12 cells with Mavrotragano significantly decreased the TBARS, CARB and ROS levels by 36.2%, 35.9% and 16.5%, respectively. In conclusion, to the best of our knowledgel, our results demonstrate for the first time that treatment with grape stem extracts at low concentrations improves the redox status of endothelial and muscle cells. Thus, grape stem extracts may be used for developing antioxidant food supplements or biofunctional foods. However, it was also found that the polyphenolic composition of grape stem extracts affects their antioxidant capacity. For example, the results suggested that trans-resveratrol, gallic acid, (+)-catechin, ferulic acid, caffeic acid, quercetin, coumaric acid and kaempferol may be essential for the antioxidant activity of grape stem extracts.
authors: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
authors: Nikolaos
authors: N
authors: Goutzourelas
authors: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
authors: Dimitrios
authors: D
authors: Stagos
authors: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
authors: Ypatios
authors: Y
authors: Spanidis
authors: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
authors: Maria
authors: M
authors: Liosi
authors: Laboratory of Nutrition Physiology and Feeding, Agricultural University of Athens, 11855 Athens, Greece.
authors: Anna
authors: A
authors: Apostolou
authors: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
authors: Alexandros
authors: A
authors: Priftis
authors: Laboratory of Nutrition Physiology and Feeding, Agricultural University of Athens, 11855 Athens, Greece.
authors: Serko
authors: S
authors: Haroutounian
authors: Laboratory of Clinical Virology, Medical School, University of Crete, 71409 Heraklion, Greece.
authors: Demetrios A
authors: DA
authors: Spandidos
authors: Department of Forensic Sciences and Toxicology, Medical School, University of Crete, 71003 Heraklion, Greece.
authors: Aristidis M
authors: AM
authors: Tsatsakis
authors: Department of Biochemistry and Biotechnology, University of Thessaly, 41221 Larissa, Greece.
authors: Demetrios
authors: D
authors: Kouretas
mesh_terms: D000818:Animals; D015415:Biomarkers; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism; D032342:Muscle Cells / Q000187:drug effects* / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D018547:Plant Stems / Q000737:chemistry*; D059808:Polyphenols / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D027843:Vitis / Q000737:chemistry*
chemical_list: D015415:Biomarkers; D016166:Free Radical Scavengers; D010936:Plant Extracts; D059808:Polyphenols; D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; D005978:Glutathione