Exposure of our skin to UVA-light may result in sunburn, inflammation, ageing and skin cancer. Studies have shown that dietary antioxidants such ascorbic acid, vitamin E and beta-carotene could reduce this damage. Scientist are now investigating the protective role of astaxanthin.
Scientist from the University College, Cork, Ireland, found that the protective effect of astaxanthin against UVA-induced photo-oxidation in cultured fibroblasts was stronger than that of lutein and beta-carotene [1]. They found that exposure to UVA-light decreased levels of antioxidant enzymes catalase and superoxide dismutase and increased levels in thiobarbituric acid reactive substances. Astaxanthin improved these indices of oxidative stress.
Another study conducted at the same university suggested that algal extract, containing a high level of astaxanthin, may be a potentially beneficial antioxidant, protecting against UVA-light induced DNA damage [2]. The protective effects of the extract was determined in three human cell types: fibroblasts, melanocytes and human intestinal CaCo-2 cells. Both the algal extract and the synthetic astaxanthin prevented DNA damage in all three cell types. UVA-light exposure increased superoxide dismutase activity and decreased glutathione levels in the fibroblast. These effects were attenuated by pre-exposing the cells with either algal extract or the synthetic astaxanthin.
Suganuma and co-workers at the Jichi Medical University, Japan, explored the effects of astaxanthin on signalling cascades in skin cells exposed to UVA-light. Damage caused by UVA-light is mainly attributed to its up-regulatory effect on the expression of matrix-metalloproteinase-1 and skin fibroblast elastase. They found that the addition of astaxanthin attenuated the induction of matrix-metalloproteinase-1 and elastase expression elicited by UVA-light. They concluded that astaxanthin could have a significant benefit on protecting against UVA-light induced skin aging such as sagging and wrinkles.
[1] Modulation of UVA light-induced oxidative stress by beta-carotene, lutein and astaxanthin in cultured fibroblasts. J Dermatol Sci. 1998 Mar;16(3):226-30.
[2] Modulatory effects of an algal extract containing astaxanthin on UVA-irradiated cells in culture. J Dermatol Sci. 2002 Oct;30(1):73-84.
[3] Astaxanthin attenuates the UVA-induced up-regulation of matrix-metalloproteinase-1 and skin fibroblast elastase in human dermal fibroblasts. J Dermatol Sci. 2010 May;58(2):136-42.
|
