Department of Cell Biology, Maria Curie-Skłodowska University, Lublin, Poland.
Biol Trace Elem Res. 2012 Jun;147(1-3):320-8. doi: 10.1007/s12011-011-9292-6. Epub 2011 Dec 10.
The effect of selenium (Se) on Vicia faba L. minor roots subjected to lead (Pb) stress was studied by investigating root growth, root viability, and antioxidant enzyme activity. The experiments were carried out on plants grown for 2 weeks on Hoagland medium supplied with 50 μM Pb in the form of lead nitrate Pb(NO(3))(2) and/or Se concentrations of 1.5 and 6 μM in the form of sodium selenite Na(2)SeO(3). It was shown that Pb reduced the root growth and caused serious damage in the roots, which was accompanied by metal accumulation in these tissues. The exposition of roots to Pb led to significant changes in the biochemical parameters: the MDA and T-SH content and glutathione peroxidase (GSH-Px) activity increased but the guaiacol peroxidase (GPOX) activity decreased. Moreover, Pb intensified O(2)(·-) production in the roots. Selenium at a lower concentration alleviated Pb toxicity which was accompanied by a decreased O(2)(·-) production in the apical parts of roots and increased the T-SH content and GPOX activity. However, higher Se concentration intensified MDA and T-SH accumulation and GPOX and GSH-Px activity in Pb-treated plant roots. At low concentration, Se improved cell viability whereas at high concentration it was pro-oxidant and enhanced the lipid peroxidation and cell membrane injury.
采用水培的方法研究了硒（Se）对 Pb 胁迫下菘蓝幼苗根系生长、根系活力和抗氧化酶活性的影响。实验在 Hoagland 培养液中进行，培养液中硝酸铅（Pb(NO(3))(2)）浓度为 50 μM，Se 以亚硒酸钠（Na(2)SeO(3)）的形式添加，浓度分别为 1.5 和 6 μM。结果表明，Pb 抑制了根系生长并导致根系严重损伤，同时伴随着金属在这些组织中的积累。Pb 的暴露导致生化参数发生显著变化：MDA 和 T-SH 含量增加，谷胱甘肽过氧化物酶（GSH-Px）活性增强，但愈创木酚过氧化物酶（GPOX）活性降低。此外，Pb 增强了根系中的 O(2)(·-)产生。较低浓度的 Se 缓解了 Pb 毒性，同时降低了根尖 O(2)(·-)的产生，增加了 T-SH 含量和 GPOX 活性。然而，较高浓度的 Se 加剧了 Pb 处理的植物根系中 MDA 和 T-SH 的积累以及 GPOX 和 GSH-Px 活性。在低浓度时，Se 提高了细胞活力，而在高浓度时，它是一种促氧化剂，加剧了脂质过氧化和细胞膜损伤。
