"Though it is known that the antioxidant vitamins play a role in human health, the mechanisms are poorly understood," said Peter Sinclair, a VA researcher and research associate at Dartmouth Medical School. "This study may lead us to an understanding of how vitamin C behaves in a particular disease."
It is still unclear whether a deficiency of vitamin C is a contributing cause of the disorder or one of its effects.
PCT is the most common form of porphyria, a group of disorders that causes chemicals called porphyrins to accumulate in the body. Porphyrins are building blocks for the production of heme, an iron-containing substance found in all body tissues. In people with PCT, a critical enzyme in the liver becomes inactivated, interfering with the production of heme from its precursor porphyrins. As a result, the porphyrins build up in the liver, spill into the blood and are carried to the skin. Untreated, people with PCT and some other porphyrias develop blisters and skin damage when exposed to sunlight.
Excess alcohol consumption, oral contraceptives and exposure to dioxins,
including those in the herbicide Agent Orange, have been known to trigger the
disorder. A more common disorder known as hemochromatosis, which causes a
dangerous buildup of iron in peoples' bodies, is linked to the same genetic
defect as PCT. The most common treatment for both diseases is bloo
Contact: Nancy Serrell
Dartmouth Medical School