Hubei Provincial Engineering Laboratory for New-type Fertilizer, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
Hubei Provincial Engineering Laboratory for New-type Fertilizer, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Pollution Processes and Environmental Criteria (Nankai University), Ministry of Education, Tianjin 300071, China; Key Laboratory of Testing and Evaluation for Agro-product Safety and Quality, Ministry of Agriculture, Guanghou 510640, China.
Ecotoxicol Environ Saf. 2015 Apr;114:179-89. doi: 10.1016/j.ecoenv.2015.01.026. Epub 2015 Jan 30.
The beneficial role of selenium (Se) in alleviation of chromium (Cr)-induced oxidative stress is well established. However, little is known about the underlying mechanism. The impacts of exogenous Se (0.1mg/L) on Cr(1mg/L)-induced oxidative stress and antioxidant systems in leaves of cabbage (Brassica campestris L. ssp. Pekinensis) were investigated by using cellular and biochemical approaches. The results showed that supplementation of the medium with Se was effective in reducing Cr-induced increased levels of lipid peroxides and superoxide free radicals (O(-)2(·)), as well as increasing activities of superoxide dismutase (SOD) and peroxidase (POD). Meanwhile, 1mg/L Cr induced loss of plasma membrane integrity, growth inhibition, as well as ultrastructural changes of leaves were significantly reversed due to Se supplementation in the medium. In addition, Se application significantly altered the subcellular distribution of Cr which transported from mitochondria, nucleus and the cell-wall material to the soluble fraction and chloroplasts. However, Se application did no significant alteration of Cr effects on osmotic adjustment accumulating products. The study suggested that Se is able to protect leaves of cabbage against Cr toxicity by alleviation of Cr induced oxidative stress, and re-distribution of Cr in the subcellular of the leaf. Furthermore, free radicals, lipid peroxides, activity of SOD and POD, and subcellular distribution of Cr can be considered the efficient biomarkers to indicate the efficiency of Se to detoxification Cr.
硒（Se）在缓解铬（Cr）诱导的氧化应激方面的有益作用已得到充分证实。然而，其潜在机制知之甚少。本研究采用细胞和生化方法，研究了外源硒（0.1mg/L）对白菜（Brassica campestris L. ssp. Pekinensis）叶片中 Cr（1mg/L）诱导的氧化应激和抗氧化系统的影响。结果表明，培养基中添加硒可有效降低 Cr 诱导的脂质过氧化物和超氧自由基（O(-)2(·)）水平升高，并提高超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性。同时，由于培养基中添加了硒，1mg/L Cr 诱导的质膜完整性丧失、生长抑制以及叶片超微结构变化得到显著逆转。此外，硒的应用显著改变了 Cr 的亚细胞分布，Cr 从线粒体、核和细胞壁物质转运到可溶部分和叶绿体。然而，硒的应用并没有显著改变 Cr 对积累渗透调节物质的影响。研究表明，硒通过缓解 Cr 诱导的氧化应激和重新分配叶片中亚细胞的 Cr，能够保护白菜叶片免受 Cr 毒性的侵害。此外，自由基、脂质过氧化物、SOD 和 POD 的活性以及 Cr 的亚细胞分布可以作为有效的生物标志物，用以指示硒解毒 Cr 的效率。
