微囊藻毒素(MC)是最普遍的,经常发现,和水生环境中严重有毒的蓝藻毒素。微囊藻毒素-亮氨酸-精氨酸(MCLR)和微囊藻毒素-精氨酸-精氨酸(MCRR)是研究最多的MC。通常,它们的水平很低,它们在环境中共存;然而,他们也可以互相交流。在这项研究中,首次研究了斑马鱼早期生命阶段(受精后2至120小时)存在MCRR时MCLR的发育毒性。我们的发现显示,MCRR治疗轻微升高甲状腺素(T4)和3,5,3'-三碘甲状腺原氨酸(T3)水平,而单独的MCLR治疗导致T3和T4水平显着增加,表明合作效果。此外,生长和发育相关基因表达水平的明显变化,伴随着生长抑制,在与MCRR和MCLR共同治疗后观察到。此外,接受MCRR和/或MCLR处理的斑马鱼幼虫显示超氧化物歧化酶水平升高,谷胱甘肽,和丙二醛,MCRR+MCLR组过氧化氢酶水平降低,表明氧化应激和脂质过氧化。因此,我们研究了MCRR和MCLR在斑马鱼发育早期阶段的协同发育毒性。
Microcystins (MCs) are the most widespread, frequently found, and seriously toxic cyanobacterial toxins in aquatic environments. Microcystin-leucine-arginine (MCLR) and microcystin-arginine-arginine (MCRR) are the most studied MCs. Normally, their levels are low and they coexist in the environment; however, they may also interact with each other. The developmental toxicity of MCLR in the presence of MCRR in the early life stage of zebrafish (from 2 to 120 h post fertilization) was investigated for the first time in this study. Our findings revealed that MCRR treatment marginally elevated thyroxine (T4) and 3,5,3\'-triiodothyronine (T3) levels, whereas MCLR treatment alone resulted in a significant increase in T3 and T4 levels, indicating a cooperative effect. Furthermore, clear changes in the expression levels of genes involved in growth and development, accompanied by growth inhibition, were observed after co-treatment with MCRR and MCLR. In addition, zebrafish larvae subjected to MCRR and/or MCLR treatment showed increased levels of superoxide dismutase, glutathione, and malondialdehyde, and decreased levels of catalase in the MCRR + MCLR group, indicating oxidative stress and lipid peroxidation. Thus, we investigated the synergistic developmental toxicity of MCRR and MCLR during the early life stages of zebrafish development.