Fluoride (F−) is a major groundwater contaminant spread across the world. In excess concentrations, F− can be detrimental to living beings. F− exposure is linked to cellular redox dyshomeostasis, leading to oxidative stress‐mediated pathologies including heart dysfunction. Due to its potent antioxidant properties, various phytochemicals are found to alleviate the symptoms of F− toxicity. Hence, we explore the protective effect of esculin (Esc), a coumarin glucoside on F−‐induced oxidative stress and cardiotoxicity in zebrafish larvae. The experimental groups consisted of NaF (50 ppm) and Esc (100 μM) groups treated alone and in combination with a control group for 6 h. The groups were maintained till 78 hpf after which the level of oxidants (ROS, LPO, and PCC) and antioxidants (GST, GSH, GPx, SOD, and CAT) were assessed. The results revealed that Esc pretreatment restored the depleted antioxidant markers and reduced the levels of oxidant in the Esc+NaF group, exhibiting its antioxidant potential. In addition, analyses of the heartbeat rate and hemoglobin integrity using o‐Dianisidine staining were conducted in the control and experimental groups. Esc treatment prevents F− induced cardiac changes including tachycardia and altered blood flow. Further, the mRNA expression level of antioxidant genes (nrf2, gstp1, hmox1a, prdx1, and nqo1) and cardiac developmental genes (bmp2b, nkx2.5, myh6, and myl7) confirmed that Esc acts as a potent free radical scavenger and antioxidant defense enhancer, protecting zebrafish larvae from NaF‐induced oxidative stress and heart dysfunction.

中文翻译：

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Esculin 是一种香豆素葡萄糖苷，可防止氟化物诱导的斑马鱼幼虫氧化应激和心脏毒性


氟化物 （F−） 是一种分布于世界各地的主要地下水污染物。在过量浓度下，F− 可能对生物有害。F− 暴露与细胞氧化还原稳态失调有关，导致氧化应激介导的病理，包括心脏功能障碍。由于其强大的抗氧化特性，发现各种植物化学物质可以缓解 F− 毒性的症状。因此，我们探讨了香豆素葡萄糖苷 esculin （Esc） 对斑马鱼幼虫中 F 诱导的氧化应激和心脏毒性的保护作用。实验组由 NaF （50 ppm） 和 Esc （100 μM） 组组成，单独处理并与对照组联合处理 6 小时。各组维持至 78 hpf，然后评估氧化剂 （ROS、LPO 和 PCC） 和抗氧化剂 （GST、GSH、GPx、SOD 和 CAT） 的水平。结果表明，Esc 预处理恢复了 Esc+NaF 组耗尽的抗氧化标志物，降低了氧化剂水平，显示出其抗氧化潜力。此外，在对照组和实验组中使用 o-Dianisidine 染色对心跳频率和血红蛋白完整性进行了分析。Esc 治疗可防止 F 诱导的心脏变化，包括心动过速和血流改变。此外，抗氧化基因 （nrf2 、 gstp1 、 hmox1a 、 prdx1 和 nqo1） 和心脏发育基因 （bmp2b 、 nkx2.5 、 myh6 和 myl7） 的 mRNA 表达水平证实，Esc 是一种有效的自由基清除剂和抗氧化防御增强剂，保护斑马鱼幼虫免受 NaF 诱导的氧化应激和心脏功能障碍。