Darr D, Combs S, Dunston S, Manning T, Pinnell S
Duke University Medical Center, Division of Dermatology, Durham, NC 27710.
Br J Dermatol. 1992 Sep;127(3):247-53. doi: 10.1111/j.1365-2133.1992.tb00122.x.
Ultraviolet radiation damage to the skin is due, in part, to the generation of reactive oxygen species. Vitamin C (L-ascorbic acid) functions as a biological co-factor and antioxidant due to its reducing properties. Topical application of vitamin C has been shown to elevate significantly cutaneous levels of this vitamin in pigs, and this correlates with protection of the skin from UVB damage as measured by erythema and sunburn cell formation. This protection is biological and due to the reducing properties of the molecule. Further, we provide evidence that the vitamin C levels of the skin can be severely depleted after UV irradiation, which would lower this organ's innate protective mechanism as well as leaving it at risk of impaired healing after photoinduced damage. In addition, vitamin C protects porcine skin from UVA-mediated phototoxic reactions (PUVA) and therefore shows promise as a broad-spectrum photoprotectant.
紫外线对皮肤的损伤部分归因于活性氧的产生。维生素C（L-抗坏血酸）因其还原特性而作为生物辅助因子和抗氧化剂发挥作用。在猪身上，局部应用维生素C已被证明能显著提高皮肤中这种维生素的水平，这与通过红斑和晒伤细胞形成来衡量的皮肤免受UVB损伤的保护作用相关。这种保护是生理性的，且归因于该分子的还原特性。此外，我们提供的证据表明，紫外线照射后皮肤中的维生素C水平会严重耗尽，这会降低该器官的固有保护机制，并使其在光诱导损伤后有愈合受损的风险。此外，维生素C能保护猪皮肤免受UVA介导的光毒性反应（PUVA），因此有望成为一种广谱光保护剂。
