Effects of a gliadin-combined plant superoxide dismutase extract on
self-perceived fatigue in women aged 50-65 years.
Author(s): Houghton CA, Steels EL, Fassett RG, Coombes JS.
Affiliation(s): School of Human Movement Studies, University of Queensland, St Lucia, Qld 4067,
Australia. christine.houghton@uqconnect.edu.au
Publication date & source: 2011, Phytomedicine. , 18(6):521-6
Fatigue syndromes exist on a continuum of severity from mild and transient to the
disabling chronic fatigue syndrome, with oxidative stress linked to its
pathogenesis. A thermolabile gliadin-combined plant superoxide dismutase (SOD)
extract has shown potential in clinical trials as a therapeutic antioxidant. This
study investigated the effects of 12 weeks of 500 mg/day of a SOD/gliadin
supplement on fatigue. Thirty-eight women aged 50-65 years with self-perceived
fatigue entered this randomized, double-blind, placebo-controlled trial. The
primary outcome measure was general fatigue determined by the Multidimensional
Fatigue Inventory (MFI). Secondary outcome measures included other measures of
fatigue from the MFI and blood measures of oxidative stress, antioxidant status
and hormones. There were no significant (P>0.05) differences between, or within
groups, for decreases in general fatigue (active=1.6%, placebo=4.1%). There were
no within or between group differences (P>0.05) in other measures of fatigue
(physical fatigue, reduced activity, reduced motivation, mental fatigue and total
fatigue score). In regard to the biochemical measures, there were non-significant
(P>0.05) differences in increases in plasma SOD activity (active=7.1%,
placebo=12.2%), plasma GPx activity (active=2.4%, placebo=0.7%), red blood cell
GPx activity (active=9.8%, placebo=4.4%). Markers of oxidative stress were
decreased but there were no differences (P>0.05) within or between groups;
malondialdehyde (active=4.1%, placebo=1.6%), F-2 isoprostanes (active=14.7%,
placebo=22.4%). There was a trend (P=0.08) for a decrease in cortisol in the
active group (24.6%), however this was not significantly different from the
decrease in the placebo participants (4.1%). DHEA differences were not
significant (P<0.05) and declined 1.3% in the active group and 14.4% in the
placebo group. In summary, the thermolabile SOD/gliadin supplement had no
significant effect on self-perceived fatigue, antioxidants, oxidative stress or
hormones in women aged 50-65 years.
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