title: Rosa roxburghii supplementation in a controlled feeding study increases plasma antioxidant capacity and glutathione redox state.
abstract: BACKGROUND
  Rosa roxburghii (RR) is a plant of which the fruit juice has been used as a medicinal remedy for a variety of diseases. It has been proposed that the putative beneficial properties are related to its antioxidant potential.
  
  
  OBJECTIVE
  We investigated the contribution of a supplemented RR fruit sample on the antioxidant status in a cohort of healthy humans.
  
  
  METHODS
  A total of 36 young, healthy and non-smoking individuals were recruited for this randomised placebo-controlled, single-blind trial. The study was diet controlled over a five-week period with a two week run-in period before participants daily received a placebo or an encapsulated supplement of RR sample. Total antioxidant capacity, glutathione redox state, glutathione reductase, glutathione peroxidase, superoxide dismutase and 8-OHdG levels were measured.
  
  
  RESULTS
  RR supplementation significantly increased plasma antioxidant capacity (p = 0.04) and GSH:GSSG ratios in blood (p = 0.03). No significant changes in 8-OHdG levels, total glutathione levels or antioxidant modulating enzymes were detected suggesting that the observed shift of the glutathione redox state probably occurs via the antioxidant mediated protection of GSH.
  
  
  CONCLUSIONS
  We conclude that these findings support the putative beneficial properties that have been linked to Rosa roxburghii as a dietary supplement that can enhance antioxidant status.
authors.affiliation: School for Chemistry and Biochemistry, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa.
authors.forename: Catharina
authors.initials: C
authors.lastname: Janse van Rensburg
authors.forename: Elardus
authors.initials: E
authors.lastname: Erasmus
authors.forename: Du Toit
authors.initials: DT
authors.lastname: Loots
authors.forename: Welma
authors.initials: W
authors.lastname: Oosthuizen
authors.forename: Johann C
authors.initials: JC
authors.lastname: Jerling
authors.forename: H Salome
authors.initials: HS
authors.lastname: Kruger
authors.forename: Roan
authors.initials: R
authors.lastname: Louw
authors.forename: Martin
authors.initials: M
authors.lastname: Brits
authors.forename: Francois H
authors.initials: FH
authors.lastname: van der Westhuizen
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage* / Q000494:pharmacology; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D019587:Dietary Supplements; D005260:Female; D005978:Glutathione / Q000097:blood* / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000097:blood / Q000378:metabolism; D005980:Glutathione Reductase / Q000097:blood / Q000378:metabolism; D006801:Humans; D008297:Male; D010084:Oxidation-Reduction; D010936:Plant Extracts / Q000008:administration & dosage* / Q000494:pharmacology; D027826:Rosa / Q000737:chemistry*; D016037:Single-Blind Method; D013482:Superoxide Dismutase / Q000097:blood / Q000378:metabolism
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D000080242:8-Hydroxy-2'-Deoxyguanosine; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D003849:Deoxyguanosine; D005978:Glutathione