title: The Peroxidation of Leukocytes Index Ratio Reveals the Prooxidant Effect of Green Tea Extract.
abstract: Despite tea increased plasma nonenzymatic antioxidant capacity, the European Food Safety Administration (EFSA) denied claims related to tea and its protection from oxidative damage. Furthermore, the Supplement Information Expert Committee (DSI EC) expressed some doubts on the safety of green tea extract (GTE). We performed a pilot study in order to evaluate the effect of a single dose of two capsules of a GTE supplement (200 mg × 2) on the peroxidation of leukocytes index ratio (PLIR) in relation to uric acid (UA) and ferric reducing antioxidant potential (FRAP), as well as the sample size to reach statistical significance. GTE induced a prooxidant effect on leukocytes, whereas FRAP did not change, in agreement with the EFSA and the DSI EC conclusions. Besides, our results confirm the primary role of UA in the antioxidant defences. The ratio based calculation of the PLIR reduced the sample size to reach statistical significance, compared to the resistance to an exogenous oxidative stress and to the functional capacity of oxidative burst. Therefore, PLIR could be a sensitive marker of redox status.
authors.affiliation: Center of Nutrition, Council for Agricultural Research and Economics (CREA-NUT), Via Ardeatina 546, 00178 Rome, Italy.
authors.forename: Ilaria
authors.identifier: 0000-0002-6210-5241
authors.initials: I
authors.lastname: Peluso
authors.affiliation: Department of Physiology and Pharmacology "V. Erspamer", "Sapienza" University of Rome, Italy.
authors.forename: Husseen
authors.initials: H
authors.lastname: Manafikhi
authors.affiliation: Center of Nutrition, Council for Agricultural Research and Economics (CREA-NUT), Via Ardeatina 546, 00178 Rome, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Raguzzini
authors.affiliation: Department of Physiology and Pharmacology "V. Erspamer", "Sapienza" University of Rome, Italy.
authors.forename: Yaroslava
authors.initials: Y
authors.lastname: Longhitano
authors.affiliation: Department of Physiology and Pharmacology "V. Erspamer", "Sapienza" University of Rome, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Reggi
authors.affiliation: Department of Physiology and Pharmacology "V. Erspamer", "Sapienza" University of Rome, Italy.
authors.forename: Christian
authors.initials: C
authors.lastname: Zanza
authors.affiliation: Department of Physiology and Pharmacology "V. Erspamer", "Sapienza" University of Rome, Italy.
authors.forename: Maura
authors.identifier: 0000-0002-0878-807X
authors.initials: M
authors.lastname: Palmery
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000032:analysis; D002392:Catechin / Q000031:analogs & derivatives / Q000494:pharmacology; D002839:Chromans / Q000494:pharmacology; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D013662:Tea / Q000737:chemistry* / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014527:Uric Acid / Q000097:blood; D055815:Young Adult
chemical_list: D000975:Antioxidants; D002839:Chromans; D010936:Plant Extracts; D013662:Tea; D014527:Uric Acid; D002392:Catechin; C045651:epigallocatechin gallate; D013755:Tetradecanoylphorbol Acetate; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid