State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Road, Nanjing, 210046, China.
Ecotoxicology. 2011 Jul;20(5):1047-56. doi: 10.1007/s10646-011-0617-1. Epub 2011 Mar 2.
Water from Taihu Lake (China) is used as a drinking source. The frequency of contamination in Taihu Lake has increased over the past decade and the bloom-forming cyanobacteria are the dominant species during eutrophication. Cyanobacteria can produce various harmful secondary substances including microcystins capable of endangering human health and ecological safety. This study investigated toxicity of ingested Taihu Lake water on mice via hepatic histopathology and matrix metalloproteinase (MMP) expression. Water was sampled from four Taihu Lake locations, Meiliang Bay 2 group (M2), Meiliang Bay 1 group (M1), Lake Center (H) and Xukou Bay (X), along a gradient of decreasing degree of eutrophication. The experimental design consists of five groups of male mice (Mus musculus, ICR): one control and four groups ingesting water from the four sampling sites for 90 days. Compared to control, M1 and M2 mice showed hepatic histopathological changes including swollen, vacuolar degeneration or inflammatory. Immunohistochemical staining demonstrated a higher expression of MMP-2 proteins in M2 group and a lower expression of MMP-9 in M1. Enzyme-linked immunosorbent assay indicated that MMP-9 concentration was significantly reduced from 0.55 to 0.28 ng/g liver weight in M2 (p < 0.05). Real time PCR revealed a down-regulation of MMP-9 mRNA by 2.2 fold in M1 and an up-regulation of MMP-2 mRNA by 1.73 fold in H. Using this mouse model as a gauge of water toxicity, our results revealed that potential health risks induced by Taihu Lake water might arise from the use of this source water by local resident.
太湖水被用作饮用水源。在过去的十年中，太湖水的污染频率不断增加，富营养化期间优势种为蓝藻。蓝藻可以产生各种有害的次生代谢产物，包括能够危害人类健康和生态安全的微囊藻毒素。本研究通过肝组织病理学和基质金属蛋白酶（MMP）表达研究了摄入太湖水对小鼠的毒性。从太湖北部梅梁湾 2 组（M2）、梅梁湾 1 组（M1）、湖心（H）和胥口湾（X）等四个不同富营养化程度的太湖水样中采集水样。实验设计包括五组雄性小鼠（Mus musculus，ICR）：一组对照和四组分别饮用四个采样点的水 90 天。与对照组相比，M1 和 M2 组小鼠肝组织出现肿胀、空泡变性或炎症等组织病理学改变。免疫组化染色显示 M2 组 MMP-2 蛋白表达升高，M1 组 MMP-9 蛋白表达降低。酶联免疫吸附试验表明，M2 组 MMP-9 浓度从 0.55 降至 0.28ng/g 肝重（p<0.05）。实时 PCR 显示，M1 组 MMP-9mRNA 下调 2.2 倍，H 组 MMP-2mRNA 上调 1.73 倍。利用该小鼠模型评估水毒性，结果表明太湖水可能会对当地居民的健康造成潜在威胁。
