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TY - JOUR AU - Dontsov, A. E. AU - Koromyslova, A. D. AU - Sakina, N. L. PY - 2013 DA - 2013/03/01 TI - Lipofuscin Component A2E Does Not Reduce Antioxidant Activity of DOPA-Melanin JO - Bulletin of Experimental Biology and Medicine SP - 624 EP - 627 VL - 154 IS - 5 AB - We studied the capacity of DOPA-melanin (natural eumelanin analog) to bind chromophore A2E of retinal pigmented epithelial cell lipofuscin granule into complexes. DOPA-melanin bound up to 200 nm A2E per 1 mg polymer; antioxidant activity of the resultant complexes was evaluated. Luminol chemiluminescence quenching in the presence of hydrogen peroxide showed that the chemiluminescence latency/concentration constants were virtually the same for DOPA-melanin and its A2E complexes. Comparison of the inhibitory effects of DOPAmelanin and DOPA-A2E complexes by rate of UV-induced peroxidation of the outer segments of photoreceptor cells showed higher inhibitory activity of the complexes in comparison with pure DOPA-melanin. Antioxidant activity of DOPA-A2E complexes towards Fe2+-ascorbateinduced peroxidation of the outer segments of photoreceptor cells was also higher than that of DOPA-melanin. The results indicated that chromophore A2E of lipofuscin granules in the studied concentrations did not attenuate the antioxidant effects of DOPA-melanin and even potentiated it. This suggested that A2E excess in retinal pigmented epithelium cells could be bound by melanosome melanin and lose its toxicity. SN - 1573-8221 UR - https://doi.org/10.1007/s10517-013-2015-6 DO - 10.1007/s10517-013-2015-6 ID - Dontsov2013 ER -