From: jay on
In some cases, vitiligo results from a combination of genetics (ie
NQO1 C609T variant) and a trigger (ie PCBs). NQO1 is a intra-cellular
enzyme that makes highly reactive quinones less reactive. Those with
NQO1 variants will be susceptible to various afflictions (ie leukemia,
cancers, ulcerative colitis, psoriasis, vitiligo, cataracts, etc).
Quinones produce highly reactive superoxides, hydrogen peroxide and
hydroxyl radicals. In addition quinones, bind to sulfur based
proteins, thus can damage DNA and create foreign proteins which
trigger an immune system response. Cells that contain certain enzymes
such as tyrosinase and myeloperoxidase are more susecptible as they
help to generate quinones. These type of cells include white cells,
nerve cells and melanocytes. Quinones result from metabolism of many
things including polyphenols/flavonoids from natural foods, internal
hormones, pesticides, antioxidant BHT/BHQ, etc. Quinones resulting
from PCBs are more toxics as they are difficult to detoxify. PCBs,
dioxins, banned nearly three decades ago, still can be found in animal
and particularly fish fats. Such quinones can exhaust a cells
antioxidants, esp GSH. For more info, search for "NQO1