Oxidative stress has been suggested as the initial
pathogenetic event in melanocyte degeneration in vitiligo. Curcumin
increase MAPK/ERK phosphorylation, to inhibit apoptosis
and pretreatment with these natural antioxidants inhibit
caspase activation, increase total antioxidant capacity, repress
intracellular reactive oxygen species generation and lipid peroxidation,
and improve mitochondrial activity, suggesting that
antioxidants such as curcumin might represent an alternative
approach to protect against vitiligo progression [41]. However,
Schallreuter and Rokos cautioned that in the presence of low
semiquinone radicals, curcumin acts as a free radical trap and
in the presence of high concentrations, the reactive oxygen
species generation is over-riding, suggesting that curcumin
may contribute to the oxidative stress in acute vitiligo and prevent
repigmentation [35]