Responses of antioxidant system in Arabidopsis thaliana suspension cells to the toxicity of microcystin-RR.
Microcystins are cyclic heptapeptide hepatoxins produced by many species of cyanobacteria. The toxic effects and mechanism of microcystins on animals have been well studied both in vivo and in vitro. It was also reported that microcystins had adverse effects on plants. However, to our knowledge, there is no information about the toxic effects and mechanism of microcystins on plant suspension cells. In this study, Arabidopsis thaliana suspension cells were exposed to a range dose of microcystin-RR. Lipid peroxidation, a main manifestation of oxidative damage, was studied and a time- and dose-dependent increase in malondiadehyde was observed. In contrast, glutathione (GSH) levels in the cells decreased after 48 h treatment with 1 and 5mg/L of microcystin-RR. The activities of superoxide dismutase (SOD) and catalase (CAT) increased significantly after 48 h exposure to 1 and 5mg/L of microcystin-RR, but glutathione S-transferase (GST) activity showed no difference compared with the control. These results clearly indicate that microcystin-RR is able to cause oxidative damage in A. thaliana suspension cells. Decrease of GSH content and increases of SOD and CAT activities reveal that the antioxidant system may play an important role in eliminating or alleviating the toxicity of microcystin-RR. The possible toxicity mechanism of microcystin-RR on the A. thaliana suspension cells is also discussed in this paper.
Yin
Liyan
L
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan 430072, China. lyyin@ihb.ac.cn
Huang
Jiaquan
J
Huang
Wenming
W
Li
Dunhai
D
Liu
Yongding
Y
D000704:Analysis of Variance; D017360:Arabidopsis / Q000187:drug effects / Q000276:immunology*; D002374:Catalase / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects / Q000276:immunology*; D008315:Malondialdehyde / Q000378:metabolism; D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; D008315:Malondialdehyde; C063855:microcystin RR; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione