微囊藻毒素LR诱导细胞毒性机制研究的细胞模型建立

ESTABLISHMENT OF CELL MODEL FOR THE STUDY OF CYTOTOXICITY INDUCED BY MICROCYSTIN-LR

以18种细胞系为材料,研究微囊藻毒素LR(20μg/mL和50μg/mL)所诱导的细胞毒性。形态观察表明,在经过30h以上的微囊藻毒素处理后,PC-3,J82,786-0,5637,VERO-E6等5种细胞出现了明显的细胞形态改变,毒素浓度越高,形态改变越厉害。微囊藻毒素LR的细胞毒性用LDH泄漏来表示。结果显示,5种毒素处理细胞的LDH泄漏呈剂量依赖性增加,其中5637和PC-3的LDH泄漏在同样的处理后较为厉害;同对照比较,SOD活力在20μg/mL MCLR处理下呈增加趋势,但在50μg/mL浓度下则下降;GSH含量在两种浓度处理下呈总体下降趋势。鉴于对微囊藻毒素敏感性差异分析,作者选择以5637细胞为基础,建立微囊藻毒素的毒理机制研究模型。

Microcystins are a group of closely related cyclic heptapeptides produced by a variety of common cyanobacteria. These toxins cause hepatocyte damage by inhibiting protein phosphastases 1 and 2A, resulting in hyperphosphorylation of a number of different proteins. Furthermore, high incidence of primary liver cancer in Qidong and Haimen in China has been associated with bloom contaminated drinking water. The mechanisms of MC-induced hepatotoxicity and tumor promotion activity have not been fully elucidated. In this study, Using 18 cell lines as materials, the cytotoxicity induced by different concentrations of microcystin-LR （20 and 50μg/mL） was studied. The morphological observation showed that five cell lines （PC-3, J82,786-0, 5637 and VERO-E6） underwent obviously morphological changes after 30h treatment with microcystin-LR （MCLR） with a dose-dependent manner. The cytoxicity of MCLR was determined by LDH leakage that showed a dose-dependent increase in five cell lines treated with MCLR, of which LDH leakage for 5637 and PC-3 were more serious under the same treatment. The SOD activity for five cell lines tended to increase in 20/μg/mL MCLR treatment but sharply decrease in 50/μg/mL MCLR treatment compared with the control cells; the GSH content decreased totally in different treatment. Based on the analysis of the sensitivity discrepancy for MCLR, 5637 cell lines was chosen for the establishment of a cell model for the study of cytotoxicity induced by microcystin-LR.