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.
Aim of study
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.
Key words Rosa roxburghii - antioxidants - glutathione redox
state - polyphenols - antioxidant
capacity