Multi- and transcriptomic changes of chronic exposure to bisphenol A reveals reproductive toxicity in male zebrafish

Syringin alleviates bisphenol A-induced spermatogenic defects and testicular injury by suppressing oxidative stress and inflammation in male zebrafish

Syringin (SRG) is a bioactive principle possessing extensive activities including scavenging of free radicals, inhibition of apoptosis, and anti-inflammatory properties. However, its effects on spermatogenic defects and testicular injury as well as the underlying mechanisms are still unclear. This study aims to investigate the protective effect of SRG on testis damage in zebrafish and explore its potential molecular events. Zebrafish testicular injury was induced by exposure to bisphenol A (BPA) (3000 μg/L) for two weeks. Fish were treated with intraperitoneal injection of SRG at different doses (5 and 50 mg/kg bodyweight) for two more weeks under BPA induction. Subsequently, the testis and sperm were collected for morphological, histological, biochemical and gene expression examination. It was found that the administration of SRG resulted in a significant protection from BPA-caused impact on sperm concentration, morphology, motility, fertility rate, testosterone level, spermatogenic dysfunction and resulted in increased apoptotic and reactive oxygen species' levels. Furthermore, testicular transcriptional profiling alterations revealed that the regulation of inflammatory response and oxidative stress were generally enriched in differentially expressed genes (DEGs) after SRG treatment. Additionally, it was identified that SRG prevented BPA-induced zebrafish testis injury through upregulation of fn1a, krt17, fabp10a, serpina1l and ctss2. These results indicate that SRG alleviated spermatogenic defects and testicular injury by suppressing oxidative stress and inflammation in male zebrafish.

The uses of zebrafish (Danio rerio) as an in vivo model for toxicological studies: A review based on bibliometrics

An in vivo model is necessary for toxicology. This review analyzed the uses of zebrafish (Danio rerio) in toxicology based on bibliometrics. Totally 56,816 publications about zebrafish from 2002 to 2023 were found in Web of Science Core Collection, with Toxicology as the top 6 among all disciplines. Accordingly, the bibliometric map reveals that "toxicity" has become a hot keyword. It further reveals that the most common exposure types include acute, chronic, and combined exposure. The toxicological effects include behavioral, intestinal, cardiovascular, hepatic, endocrine toxicity, neurotoxicity, immunotoxicity, genotoxicity, and reproductive and transgenerational toxicity. The mechanisms include oxidative stress, inflammation, autophagy, and dysbiosis of gut microbiota. The toxicants commonly evaluated by using zebrafish model include nanomaterials, arsenic, metals, bisphenol, and dioxin. Overall, zebrafish provide a unique and well-accepted model to investigate the toxicological effects and mechanisms. We also discussed the possible ways to address some of the limitations of zebrafish model, such as the combination of human organoids to avoid species differences.