Zhao Q, Li Y, Xu J, Liu R, Li W
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China.
Int J Radiat Biol. 2005 Feb;81(2):169-75. doi: 10.1080/09553000400029536.
The aim was to study the protective effects of fullerenols, C60(OH)x, on Stylonychia mytilus cells exposed to 60Co gamma-rays and the probable mechanisms of fullerenols protection. Ciliated protozoans Smytilus, kept in solutions of fullerenols at different concentrations, were irradiated with 60Co gamma-rays to various dose levels. Surviving cells were counted each day over 5 days after irradiation, and the surviving fraction was calculated. The relations of the surviving fraction to radiation dose and to fullerenols concentration were studied. Superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and lipofusion (LIP) levels in S. mytilus were also measured. The surviving fraction of S. mytilus decreased with increasing gamma-ray doses from 100 to 2000 Gy. Fullerenols enhanced the surviving fraction, except for the highest gamma-ray dose level. The maximum protection by fullernols occurred at a concentration of 0.10 mg ml(-1). However, fullerenols at concentration of 0.25 mg ml(-1) yielded a surviving fraction lower than that for the control sample. Fullerenols at a concentration of 0.10 mg ml(-1) increased the SOD and CAT activities in the gamma-ray plus fullerenols (gamma + F) group compared with the levels in both the gamma-ray (gamma) group (p < 0.01) and the control group (p < 0.01). The MDA and LIP levels in the gamma + F groups (p < 0.01) were significantly lower than that in both the control group (p < 0.05) and the gamma group (p < 0.01). At a concentration of 0.25 mg ml(-1), fullerenols reduced the SOD and CAT activities, but increased the MDA and LIP level compared with the control. There was no significant difference in SOD and CAT activities between the gamma + F group and gamma group. While the MDA and LIP level in the gamma + F and gamma groups were similar at a dose of 500 Gy, the LIP level in the gamma + F group was significantly higher than that in the gamma group (p < 0.01) at a dose of 2000 Gy. Fullerenols are good radiation protectors for the protozoan S. mytilus exposed to gamma-rays. The effectiveness of radioprotection depends on both fullerenols concentration and gamma-ray dose. The protective effect of fullerenols on damage induced by gamma-rays seems to be mediated, at least in part, through their anti-oxidative and radical scavenging activities.
本研究旨在探讨富勒醇（C60(OH)x）对暴露于60Coγ射线的贻贝棘尾虫细胞的保护作用及其可能的保护机制。将不同浓度富勒醇溶液中的纤毛原生动物贻贝棘尾虫用60Coγ射线照射至不同剂量水平。照射后5天内每天对存活细胞进行计数，并计算存活分数。研究了存活分数与辐射剂量及富勒醇浓度之间的关系。还测定了贻贝棘尾虫中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、丙二醛（MDA）和脂褐素（LIP）的水平。随着γ射线剂量从100 Gy增加到2000 Gy，贻贝棘尾虫的存活分数降低。除最高γ射线剂量水平外，富勒醇提高了存活分数。富勒醇的最大保护作用出现在浓度为0.10 mg/ml时。然而，浓度为0.25 mg/ml的富勒醇产生的存活分数低于对照样品。与γ射线组（γ组，p < 0.01）和对照组（p < 0.01）相比，浓度为0.10 mg/ml的富勒醇使γ射线加富勒醇（γ + F）组中的SOD和CAT活性增加。γ + F组中的MDA和LIP水平（p < 0.01）显著低于对照组（p < 0.05）和γ组（p < 0.01）。在浓度为0.25 mg/ml时，富勒醇降低了SOD和CAT活性，但与对照相比增加了MDA和LIP水平。γ + F组和γ组之间的SOD和CAT活性没有显著差异。虽然在500 Gy剂量下γ + F组和γ组中的MDA和LIP水平相似，但在2000 Gy剂量下γ + F组中的LIP水平显著高于γ组（p < 0.01）。富勒醇是暴露于γ射线的原生动物贻贝棘尾虫的良好辐射防护剂。辐射防护效果取决于富勒醇浓度和γ射线剂量。富勒醇对γ射线诱导损伤的保护作用似乎至少部分是通过其抗氧化和自由基清除活性介导 的。
