紫外线照射对秀丽隐杆线虫形态、寿命和ROS含量的影响

目的探讨紫外线照射对秀丽隐杆线虫形态、寿命和ROS含量的影响。方法线虫同步化培养至L4期,随机分为0 J/m2(对照组)、20 J/m2、40 J/m2、60 J/m2、80 J/m2、100 J/m2、120 J/m2和200 J/m2照射组共8组,用紫外交联仪进行照射。于照后1h、6 h、12 h和24 h,观察各组线虫形态变化;观察记录线虫死亡数和存活数,用于分析死亡率和寿命;于照后8 h、12 h和24 h,检测各组线虫体内ROS含量。结果与对照组比较,照后6～24 h,40 J/m2组线虫形态未观察到明显改变,而80 J/m2和120J/m2组中持续出现体型较小的线虫,且120 J/m2组明显多于80J/m2组。照后7 d各照射组线虫死亡率均高于对照组,且剂量越大死亡率越高,呈一定量效关系。各照射组线虫平均寿命均低于对照组,且照射剂量越大平均寿命越短。照后24 h内,80 J/m2和120 J/m2组线虫的荧光强度明显高于对照组;于照后8～24 h,120 J/m2组荧光强度均强于80 J/m2组。结论紫外线照射能明显诱导线虫形态学改变,影响线虫正常生长发育;大剂量照射可致线虫寿命缩短,推测线虫体内活性氧(ROS)含量增加可能是导致其寿命缩短的原因之一。

Effects of UVC irradiation on morphology, life span and ROS in Caenorhabditis elegans

Objective To study the effects of uhraviolet C （UVC） radiation on morphology, life span and ROS in Caenorhabditis elegans. Methods The worms age - synchronized and developed to larval stage L4, were randomly divided into 0 j/m2（control group） , 20 J/m2, 40 J/m2, 60 J/m2 80 J/m2, 100 J/m2, 120 J/m2 and 200 J/m2 irradiation groups. Then the worms were irradiated by UVC in a UV Stratalinker. At 1 h, 6 h, 12 h and 24 h after irradiation, the morphological changes of worms in each group were observed, and the number of alive or dead worms were counted and recorded to analyze the mortality and life span. The level of ROS in the worms were detected at 8 h, 12 h and 24 h after irradiation. Results At 6 - 24 h after irradiation, compared with the control group, there were no morphologi- cal changes in the worms of the 40 J/m2 group, however, smaller worms in the 80 J/m2 and 120 J/m2 groups appeared continuously and the worm numbers in the 120 J/m2 group were significantly more than those in the 80 J/m2 group. At 7 d after irradiation, the worm mortality rate of each irradiation group was higher than that of the control group. As the dose increased, the warm mortality was increased, with a certain dose - effect relationship. The average life span of the worms in all irradiation groups were shorter than that of the control group, and as the dose increased, the average life span of worms was shortened. Within 24 h after irradiation, the fluorescence intensity of worms in the 80 J/m2 and 120 J/m2 groups was significantly higher than that in the control group, and fluorescence intensity in the 120 J/m2 group was stronger than that in the 80 J/m2 group at 8 - 24 h after irradiation. Conclusions UVC irradiation can induce obvious morphological changes in Caenorhabditis elegans and impede their growth and develop- ment. High doses of UVC irradiation can lead to a shorter life span of the worms. Therefore, it is sup- posed that the increment of ROS in worms may be one of mechanisms leading to shortened life span of the worms.