The widely used antifoulant tributyltin chloride (TBT) is highly toxic to aquatic organisms. In the present study, four-week-old Japanese medaka (Oryzias latipes) juveniles were orally exposed to TBT at 1 and 10 ng/g bw/d for 1, 2, and 4 weeks, respectively. Half of the tested medaka juveniles showed bone morphology alterations in both 1 and 10 ng/g bw/d TBT 4-week exposure groups. Nile Red (NR) staining showed that the juveniles exposed to 1 ng/g bw/d TBT for 2 and 4 weeks had significantly enlarged adipocyte areas. The mRNA-Seq analysis indicated that 1 ng/g bw/d TBT exposure for 2 weeks affected bone morphology through developmental processes. The GO and KEGG analyses suggested that the adipogenic effect of TBT observed in this study may be induced by metabolic processes, oxidative phosphorylation, and fatty acid degradation and metabolism pathways. Therefore, both morphological observation and mRNA-Seq analysis showed obesogenic effects and developmental toxicity of TBT to juvenile Japanese medaka.

广泛使用的防污剂氯化三丁基锡 (TBT) 对水生生物有剧毒。在本研究中，4 周龄的日本青鳉（Oryzias latipes) 幼鱼分别以 1 和 10 ng/g bw/d 的剂量口服暴露于 TBT 1、2 和 4 周。在 1 和 10 纳克/克体重/天 TBT 4 周暴露组中，一半的受试青鳉幼鱼显示出骨骼形态改变。尼罗红 (NR) 染色显示，暴露于 1 ng/g bw/d TBT 2 和 4 周的幼鱼脂肪细胞面积显着扩大。mRNA-Seq 分析表明，1 ng/g bw/d TBT 暴露 2 周会通过发育过程影响骨骼形态。GO 和 KEGG 分析表明，本研究中观察到的 TBT 的脂肪生成作用可能是由代谢过程、氧化磷酸化、脂肪酸降解和代谢途径诱导的。因此，形态学观察和 mRNA-Seq 分析均表明 TBT 对日本青鳉幼鱼有致肥胖作用和发育毒性。