LIPOSOLUBLE VITAMINS AND NATURALLY-OCCURRING CAROTENOIDS IN PORPHYRIA-CUTANEA-TARDA

The authors consider two groups of patients with overt sporadic porphy ria cutanea tarda (PCT) from different continents, with the aim of eva luating the possible impairment of the liposoluble antioxidative syste m, given the possible synergic effect of porphyrins and iron in promot ing oxidative cellular damage. Twenty-three Italian outpatients with o vert sporadic PCT and 11 outpatients with PCT from Buenos Aires (Argen tina) were matched with 60 patients with liver cirrhosis and 52 health y Italian controls. Serum levels of alpha- and beta-carotene, cryptoxa nthin, zeaxanthin, lutein, lycopene, retinol and alpha-tocopherol were detected by a high-performance liquid chromatographic technique devis ed in our laboratory, which afforded an accurate and simultaneous reso lution of ah these compounds. The results point to a significant reduc tion in plasma levels of alpha- and beta-carotene in both the PCT popu lations with respect not only to controls, but also to the cirrhotic p opulation, which had more severe liver damage. Moreover, other caroten oids with proven antioxidative properties, like cryptoxanthin and lyco pene, are greatly reduced in our PCT populations. This confirms the su ggested synergic effect of iron and porphyrins in the oxidative intrac ellular damage with consequent depletion of antioxidative liposoluble molecules.