Ionizing radiation, as an increasingly serious environmental pollutant, has aroused widespread public concern. Melatonin, as an indole heterocyclic compound, is known to have anti-inflammatory and antioxidant effects. However, few studies have considered the comprehensive impact of melatonin on radiation damage. In this study, we used zebrafish as experimental materials and employed methods such as acridine orange staining, enzyme-linked immunosorbent assay (ELISA), video tracking for automated behavior analysis, microscope imaging, and real-time fluorescence quantitative analysis. Zebrafish embryos at 2 h post-fertilization (hpf) were treated under four different experimental conditions to assess their growth, development, and metabolic consequences. Our findings indicate that 0.10 Gy gamma radiation significantly augments body length, eye area, spine width, and tail fin length in zebrafish, along with a marked increase in oxidative stress (P < 0.05). Moreover, it enhances cumulative swimming distance, time, and average speed, suggesting elevated activity levels. We observed circadian rhythm phase shifts, peak increases, and cycle shortening, accompanied by abnormal expression of genes pivotal to biological rhythms, exercise, melatonin synthesis, apoptosis/anti-apoptosis, and oxidation/antioxidant balance. The inclusion of melatonin (1 × 10-5 mol/L MLT) ameliorated these radiation-induced anomalies, while its independent effect on zebrafish was negligible. Melatonin can regulate oxidative stress responses, hinders apoptosis responses, and reprogramming the expression of rhythm-related genes in zebrafish embryos after reprogramming radiation stimulation. Overall, our research highlights melatonin's critical role in countering the biological damage inflicted by gamma radiation, proposing its potential as a therapeutic agent in radiation protection.

中文翻译：

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褪黑激素对辐射诱导的斑马鱼行为节律中断的保护作用 （danio rerio）


电离辐射作为一种日益严重的环境污染物，引起了公众的广泛关注。褪黑激素作为一种吲哚杂环化合物，已知具有抗炎和抗氧化作用。然而，很少有研究考虑褪黑激素对辐射损伤的综合影响。在本研究中，我们以斑马鱼为实验材料，采用吖啶橙染色、酶联免疫吸附测定 （ELISA）、视频跟踪进行自动行为分析、显微镜成像和实时荧光定量分析等方法。在四种不同的实验条件下处理受精后 2 小时 （hpf） 的斑马鱼胚胎，以评估其生长、发育和代谢后果。我们的研究结果表明，0.10 Gy γ 辐射显着增加了斑马鱼的体长、眼面积、脊柱宽度和尾鳍长度，同时氧化应激显着增加 （P < 0.05）。此外，它还提高了累积游泳距离、时间和平均速度，表明活动水平升高。我们观察到昼夜节律相移、峰值增加和周期缩短，并伴有对生物节律、运动、褪黑激素合成、细胞凋亡/抗细胞凋亡和氧化/抗氧化平衡至关重要的基因的异常表达。褪黑激素 （1 × 10-5 mol/L MLT） 的加入改善了这些辐射诱导的异常，而其对斑马鱼的独立影响可以忽略不计。褪黑激素可以调节氧化应激反应，阻碍细胞凋亡反应，并在重编程辐射刺激后重编程斑马鱼胚胎中节律相关基因的表达。 总体而言，我们的研究强调了褪黑激素在对抗伽马辐射造成的生物损伤方面的关键作用，并提出了其作为辐射防护治疗剂的潜力。