用凝胶电泳法研究羟基肉桂酸衍生物对DNA的辐射保护效应

GEL ELECTROPHORESIS STUDY OF RADIOPROTECTIVE EFFECT OF HYDROXY CINNAMIC ACID DERIVATIVES ON DNA

ABSTRACT The radioprotective effect exerted by hydroxy cinnamic acid derivati-ves on the radiation damage of DNA, such as double-strand break (DSB). intermole-cular crosslinking (CL), has been studied by gel electrophoresis. The molecular lengthdistribution of DNA can be measured by this method, and by comparing average mo-lecular length of DNA before and after irradiation, the frequency of DSB and CL canbe determined quantitatively, The radioprotective effect of caffeic acid and sinapine oncalf thymus DNA in binary system at room temperature have been determined. Bothcaffeic acid and sinapine reveal apparent protective effects and the former is strongerthan the latter. The mechanism of radioprotection at room temperature has been discus-sed. Based. on this finding, combined with the previous ESR study and an analysis ofthe molecular structure about these two protectors, it is suggested that the target isprotected as a result of hydrogen atom transfering from protector to target.