Kurkuma
tegen ontstekingen en goed bij retinopathie.*
Uit
een dierenstudie met ratten blijkt dat kurkuma goed werk doet tegen ontstekingen
en tegen oxidatieschade. Oxidatieschade en ontstekingen liggen mede ten
grondslag aan retinopathie (aantastingen van het netvlies) bij mensen met
diabetes. In deze studie kregen de ratten met diabetes of een voeding aangevuld
met kurkuma of geen aanvulling. Na zes weken was de antioxidatie capaciteit bij
de ratten zonder aanvulling met 30% afgenomen te zijn terwijl bij zij die
kurkuma gegeten hadden was die capaciteit gelijk gebleven. De glutathionwaarden
bleken in de groep zonder aanvullingen 50% lager te liggen terwijl dit in de
kurkamagroep ongeveer 30% was dan bij ratten zonder diabetes. Het aantal
ontsteking veroorzakende proteïnes bleek in de ratten zonder aanvulling wel
verdubbeld te zijn terwijl in de kurkumagroep de verhoging slechts een
paar % bedroeg in vergelijking met ratten zonder diabetes.
Effects of
curcumin on retinal oxidative stress and inflammation in diabetes
Abstract (provisional)
The
complete article is available as a provisional
PDF. The fully formatted
PDF and HTML versions are in production.
Background
Oxidative
stress and inflammation are implicated in the pathogenesis of retinopathy in
diabetes. The aim of this study is to examine the effect of curcumin, a
polyphenol with antioxidant and anti-inflammatory properties, on
diabetes-induced oxidative stress and inflammation in the retina of rats.
Methods
A
group of streptozotocin-induced diabetic rats received powdered diet
supplemented with 0.05% curcumin (w/w), and another group received diet without
curcumin. The diets were initiated soon after induction of diabetes, and the
rats were sacrificed 6 weeks after induction of diabetes. The retina was used to
quantify oxidative stress and pro-inflammatory markers.
Results
Antioxidant
capacity and the levels of intracellular antioxidant, GSH (reduced form of
glutathione) levels were decreased by about 30-35%, and oxidatively modified DNA
(8-OHdG) and nitrotyrosine levels were increased by 60-70% in the retina of
diabetic rats. The levels of interleukin-1β (IL-1β) and
vascular endothelial growth factor (VEGF) were elevated by 30% and 110%
respectively, and the nuclear transcription factor (NF-kB) was activated by 2
fold. Curcumin administration prevented diabetes-induced decrease in the
antioxidant capacity, and increase in 8-OHdG and nitrotyrosine; however, it had
only partial beneficial effect on retinal GSH. Curcumin also inhibited
diabetes-induced elevation in the levels of IL-1β, VEGF and NF-kB. The
effects of curcumin were achieved without amelioration of the severity of
hyperglycemia.
Conclusions
Thus,
the beneficial effects of curcumin on the metabolic abnormalities postulated to
be important in the development of diabetic retinopathy suggest that curcumin
could have potential benefits in inhibiting the development of retinopathy in
diabetic patients.
Nutrition & Metabolism 2007, 4:8 doi:10.1186/1743-7075-4-8 (Mei 2007) (Opm. Meer over kurkuma.)