Bez G C, Jordão B Q, Vicentini V E, Mantovani M S
Departamento de Biologia Geral, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Paraná, Brazil.
Mutat Res. 2001 Oct 18;497(1-2):139-45. doi: 10.1016/s1383-5718(01)00251-0.
Chlorophyll and its derivatives are examples of plant compounds (purified and/or extracted) which appear to protect DNA from damage caused by chemical or physical agents, although some studies have identified clastogenic activity of these compounds. This study was carried out to assess the genotoxic activity of chlorophyll-a (Chl-a), -b (Chl-b) and chlorophyllin (Chl) and their antigenotoxic activity against the DNA damage induced by methyl methanesulphonate (MMS) under conditions of simultaneous, pre-, post-treatment, and simultaneous treatment after pre-incubation of the chemical with MMS. The micronucleus (MN) test was used in binucleated cells (induced by cytochalasin-B) of a mammalian cell line (V79). The three concentrations of Chl-a, Chl-b or Chl (0.1375, 0.275, 0.55microM) were not genotoxic and the genotoxic action of MMS (400microM) decreased (74-117%) under all treatment conditions. The results showed that there was no significant difference among the treatment types, the concentration or the nature of chlorophyll used. The data obtained suggest that Chl-a, Chl-b and Chl when associated with the DNA damaging agent, MMS, may protect the DNA by desgenotoxic action and/or by bio-antigenotoxic mechanisms, with the similar efficiency.
叶绿素及其衍生物是植物化合物（纯化和/或提取）的例子，这些化合物似乎能保护DNA免受化学或物理因素造成的损伤，尽管一些研究已经确定了这些化合物的致断裂活性。本研究旨在评估叶绿素a（Chl-a）、叶绿素b（Chl-b）和叶绿酸（Chl）的遗传毒性活性，以及它们在与甲磺酸甲酯（MMS）同时处理、预处理、后处理以及在将化学物质与MMS预孵育后的同时处理条件下，对MMS诱导的DNA损伤的抗遗传毒性活性。微核（MN）试验用于哺乳动物细胞系（V79）的双核细胞（由细胞松弛素B诱导）。三种浓度的Chl-a、Chl-b或Chl（0.1375、0.275、0.55微摩尔）没有遗传毒性，并且在所有处理条件下，MMS（400微摩尔）的遗传毒性作用降低了（74%-117%）。结果表明，处理类型、所用叶绿素的浓度或性质之间没有显著差异。所获得的数据表明，Chl-a、Chl-b和Chl与DNA损伤剂MMS结合时，可能通过去遗传毒性作用和/或生物抗遗传毒性机制以相似的效率保护DNA。
