Coolia tropicalis is a species of benthic and epiphytic toxic algae, which can produce phycotoxins that intoxicate marine fauna. In this study, the potential toxic effects of C. tropicalis on fish were investigated using larval marine medaka (Oryzias melastigma) as a model to evaluate fish behavior, physiological performance, and stress-induced molecular responses to exposure to two sublethal concentrations (LC₁₀ and LC₂₀) of hydrophilic algal lysates. Exposure to C. tropicalis lysates inhibited swimming activity, activated spontaneous undirected locomotion, altered nerve length ration, and induced early development abnormalities, such as shorter eye diameter, body as well as axon length. Consistent with these abnormalities, changes in the expression of genes associated with apoptosis (CASPASE-3 and BCL-2), the inflammatory response (IL-1β and COX-2), oxidative stress (SOD), and energy metabolism (ACHE and VHA), were also observed. This study advances our understanding of the mechanisms of C. tropicalis toxicity in marine fish in the early life stages and contributes to future ecological risk assessments of toxic benthic dinoflagellates.

热带小木是一种底栖和附生有毒藻类，可以产生使海洋动物陶醉的藻毒素。在这项研究中，使用幼虫海洋med（Oryzias melastigma）作为模型，研究了热带假丝酵母对鱼类的潜在毒性作用，以评估鱼类行为，生理性能和应力诱导的分子对暴露于两种亚致死浓度的分子响应（LC ₁₀和LC ₂₀）的亲水性藻类裂解物。暴露于热带假丝酵母裂解物抑制游泳活动，激活自发性无方向运动，改变神经长度比例，并诱发早期发育异常，例如眼球直径，身体和轴突长度变短。与这些异常相一致的是，与凋亡相关的基因表达（CASPASE-3和BCL-2），炎症反应（IL-1β和COX-2），氧化应激（SOD）和能量代谢（ACHE和VHA）发生变化），也进行了观察。这项研究提高了我们对热带假丝酵母的机制的理解。 鱼类在生命的早期阶段具有毒性，并有助于对有毒底栖鞭毛藻的未来生态风险评估。