Lin Wang, Hu Fen, Zou Wansheng, Wang Suqin, Shi Pengling, Li Li, Yang Jifeng, Yang Pinhong
College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China.
Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming 650500, China.
Toxins (Basel). 2024 Dec 18;16(12):549. doi: 10.3390/toxins16120549.
Microcystin-leucine arginine (MC-LR) poses a serious threat to aquatic animals during cyanobacterial blooms. Recently, biochar (BC), derived from rice straw, has emerged as a potent adsorbent for eliminating hazardous contaminants from water. To assess the joint hepatotoxic effects of environmentally relevant concentrations of MC-LR and BC on fish, male adult zebrafish () were sub-chronically co-exposed to varying concentrations of MC-LR (0, 1, 5, and 25 μg/L) and BC (0 and 100 μg/L) in a fully factorial experiment. After 30 days exposure, our findings suggested that the existence of BC significantly decreased MC-LR bioavailability in liver. Furthermore, histopathological analysis revealed that BC mitigated MC-LR-induced hepatic lesions, which were characterized by mild damage, such as vacuolization, pyknotic nuclei, and swollen mitochondria. Compared to the groups exposed solely to MC-LR, decreased malondialdehyde (MDA) and increased catalase (CAT) and superoxide dismutase (SOD) were noticed in the mixture groups. Concurrently, significant changes in the mRNA expression levels of Nrf2 pathway genes (, , , , , and ) further proved that BC reduces the oxidative damage induced by MC-LR. These findings demonstrate that BC decreases MC-LR bioavailability in the liver, thereby alleviating MC-LR-induced hepatotoxicity through the Nrf2 signaling pathway in zebrafish. Our results also imply that BC could serve as a potentially environmentally friendly material for mitigating the detrimental effects of MC-LR on fish.
微囊藻毒素 - 亮氨酸精氨酸（MC - LR）在蓝藻水华期间对水生动物构成严重威胁。最近，源自稻草的生物炭（BC）已成为一种有效的吸附剂，可用于去除水中的有害污染物。为了评估环境相关浓度的MC - LR和BC对鱼类的联合肝毒性作用，在一项全因子实验中，将成年雄性斑马鱼（）亚慢性联合暴露于不同浓度的MC - LR（0、1、5和25μg/L）和BC（0和100μg/L）中。暴露30天后，我们的研究结果表明，BC的存在显著降低了肝脏中MC - LR的生物利用度。此外，组织病理学分析显示，BC减轻了MC - LR诱导的肝脏损伤，其特征为轻度损伤，如空泡化、核固缩和线粒体肿胀。与仅暴露于MC - LR的组相比，混合组中丙二醛（MDA）含量降低，过氧化氢酶（CAT）和超氧化物歧化酶（SOD）含量增加。同时，Nrf2途径基因（、、、、和）的mRNA表达水平发生显著变化，进一步证明BC可减少MC - LR诱导的氧化损伤。这些发现表明，BC降低了肝脏中MC - LR的生物利用度，从而通过斑马鱼中的Nrf2信号通路减轻了MC - LR诱导的肝毒性。我们的结果还表明，BC可作为一种潜在的环境友好材料，用于减轻MC - LR对鱼类的有害影响。
