Neurotoxin β-N-methylamino-L-alanine (BMAA) has been widely detected in diverse aquatic organisms and hypothesized as an environmental risk to neurodegenerative diseases in humans. However, the knowledge of its toxicity to marine organisms requires attention. In the present study, embryos and sperm of the sea urchin, Lytechinus pictus, were used to assess the toxicity of BMAA. Effects of BMAA on fertilization and development of sea urchin embryos were measured, and its impacts on efflux transport of sea urchin blastula were also assayed. Results demonstrated that the fertilization and development of embryos were significantly inhibited by high concentrations of BMAA above 300 μg L-1. The EC50 values indicated by active swimming larvae and total larvae numbers at 96 HPF (hours post fertilization) were 165 μg L-1 (1.4 μmol L-1) and 329 μg L-1 (2.8 μmol L-1), respectively. Additionally, sperm exposed to BMAA for 10 min significantly reduced the fertilization ratio of sea urchin eggs. However, the ABC transport activity on the cytomembrane of sea urchin blastula was not inhibited by the presence of BMAA at 50 μg L-1, even up to 500 μg L-1. Abnormal division and developmental malformations occurred at different developmental stages for sea urchin embryos exposed to BMAA at 500 μg L-1. The inhibitory effects of BMAA on sea urchin embryos were reported at the first time in this study, for which the toxicological mechanisms will be explored in future studies.

中文翻译：

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神经毒素β-N-甲基氨基-L-丙氨酸对海胆Lytechinus pictus的受精和早期发育的抑制作用。

神经毒素β-N-甲基氨基-L-丙氨酸（BMAA）已在多种水生生物中广泛检测到，并被认为对人类神经退行性疾病具有环境风险。但是，有关其对海洋生物毒性的知识需要引起重视。在本研究中，海胆（Lytechinus pictus）的胚胎和精子用于评估BMAA的毒性。测量了BMAA对海胆胚胎受精和发育的影响，并分析了其对海胆囊胚外排运输的影响。结果表明，高于300μgL-1的高浓度BMAA显着抑制了胚胎的受精和发育。在96 HPF（受精后数小时）时，活跃的游泳幼虫和幼虫总数所指示的EC50值为165μgL-1（1.4μmolL-1）和329μgL-1（2。8μmolL-1）。另外，暴露于BMAA的精子10分钟显着降低了海胆卵的受精率。但是，在50μgL-1甚至高达500μgL-1的BMAA的存在下，海胆囊小球细胞膜上的ABC转运活性并未受到抑制。在500μgL-1下暴露于BMAA的海胆胚胎在不同的发育阶段发生异常分裂和发育畸形。首次报道了BMAA对海胆胚胎的抑制作用，其毒理学机理将在以后的研究中探讨。在50μgL-1甚至高达500μgL-1的BMAA的存在下，海胆囊小球细胞膜的ABC转运活性均不受抑制。在500μgL-1下暴露于BMAA的海胆胚胎在不同的发育阶段发生异常分裂和发育畸形。首次报道了BMAA对海胆胚胎的抑制作用，其毒理学机理将在以后的研究中探讨。在50μgL-1甚至高达500μgL-1的BMAA的存在下，海胆囊小球细胞膜的ABC转运活性均不受抑制。在500μgL-1下暴露于BMAA的海胆胚胎，在不同的发育阶段发生了异常的分裂和发育畸形。首次报道了BMAA对海胆胚胎的抑制作用，其毒理学机理将在以后的研究中探讨。