Zhang Xu-hong, Lin Ai-jun, Su Yu-hong, Zhu Yong-guan
Department of Soil Environmental Sciences, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Huan Jing Ke Xue. 2006 Apr;27(4):787-93.
DNA damages and programmed cell death in leaves of Vicia faba induced by Cd were studied with methods including alkaline/alkaline, alkaline/neutral, neutral/neutral comet assay and DAPI staining. Types of DNA damages induced by Cd were different detected by three types of comet assay. Single strand breakage and alkali labile sites were detected in the leaves of Vicia faba with 5 mg x L(-1) Cd treatment by alkaline/alkaline comet assay. With 10 mg x L(-1) Cd treatments, double strand breakages began to be detected by neutral/neutral comet assay. However, single strand breakages and alkali labile sites were still the main types of DNA damages. Three types of DNA damages increased significantly with 20 mg x L(-1) Cd treatment especially double strand breakages. These results indicated that DNA damages increased with increasing of Cd concentration, which was consistent with the programmed cell death induced by Cd. The result of apoptosis detected by DAPI staining indicated that there existed a relationship between apoptosis and DNA damage. These results indicated that Cd was an element with high genotoxicity and DNA damage was one of the mechanisms of cell apoptosis induced by Cd.
采用碱性/碱性、碱性/中性、中性/中性彗星试验和DAPI染色等方法，研究了镉诱导蚕豆叶片中的DNA损伤和程序性细胞死亡。通过三种彗星试验检测到镉诱导的DNA损伤类型不同。用碱性/碱性彗星试验在5mg x L(-1)镉处理的蚕豆叶片中检测到单链断裂和碱不稳定位点。在10mg x L(-1)镉处理下，通过中性/中性彗星试验开始检测到双链断裂。然而，单链断裂和碱不稳定位点仍然是DNA损伤的主要类型。在20mg x L(-1)镉处理下，三种类型的DNA损伤显著增加，尤其是双链断裂。这些结果表明，DNA损伤随着镉浓度的增加而增加，这与镉诱导的程序性细胞死亡一致。DAPI染色检测的细胞凋亡结果表明，细胞凋亡与DNA损伤之间存在关系。这些结果表明，镉是一种具有高遗传毒性的元素，DNA损伤是镉诱导细胞凋亡的机制之一。
