天然抗氧化剂对核黄素的保护作用及对 DNA 和 RNA 碱基的 UVB 敏化降解作用。

Protection of riboflavin and UVB sensitized degradation of DNA and RNA bases by natural antioxidants.

机构信息

Department of Chemistry and Biochemistry, ISES Labs, Russell Sage College, Troy, NY 12180, USA.

出版信息

Ecotoxicol Environ Saf. 2012 Apr;78:86-90. doi: 10.1016/j.ecoenv.2011.11.011. Epub 2011 Dec 12.

DOI:10.1016/j.ecoenv.2011.11.011

Abstract

Riboflavin (RF) is a potent photosensitizer producing extensive degradation of purine and pyrimidine derivatives of nucleic acids under UVA, UVB and sunlight. In this study we have demonstrated that reactive O(2) species generated by photosensitized RF under UVB were responsible for the degradation of DNA and RNA bases. While (1)O(2) accounted for the degradation of adenine, guanine, thymine and uracil, O(2)(-·)also contributed to partial degradation of adenine. Cytosine remained unaffected by the synergistic action of RF and UVB. Ascorbic acid, glutathione, glycolic acid and quercetin showed remarkable protection (88-100%) against photodegradation of bases. Sorbitol was effective in preventing photodegradation of guanine. These naturally occurring antioxidants are potential candidates for prevention against oxidative stress caused by photosensitization.

摘要

核黄素（RF）是一种有效的光敏剂，在 UVA、UVB 和阳光的照射下，会广泛降解核酸中的嘌呤和嘧啶衍生物。在这项研究中，我们已经证明，在 UVB 下由光敏化 RF 产生的活性氧（O2）物种负责 DNA 和 RNA 碱基的降解。虽然 1O2 负责腺嘌呤、鸟嘌呤、胸腺嘧啶和尿嘧啶的降解，但 O2（-·）也有助于部分降解腺嘌呤。胞嘧啶不受 RF 和 UVB 的协同作用影响。抗坏血酸、谷胱甘肽、乙醇酸和槲皮素对碱基的光降解表现出显著的保护作用（88-100%）。山梨醇可有效防止鸟嘌呤的光降解。这些天然存在的抗氧化剂是预防光敏化引起的氧化应激的潜在候选物。