High-Salt Exposure Disrupts Cardiovascular Development in Zebrafish Embryos, Brachyodanio rerio , via Calcium and MAPK Signaling Pathways

Cardiovascular disease and hypertension are major global health challenges, and increasing dietary salt intake is a known contributor. Emerging evidence suggests that excessive salt exposure during pregnancy may impact fetal development, yet its effects on early embryogenesis remain poorly understood. In this study, we used zebrafish ( Danio rerio ) embryos as a model to investigate the developmental and molecular consequences of high-salt exposure during early vertebrate development. Embryos subjected to elevated salt levels exhibited delayed hatching, reduced heart rates, and significant alterations in gene expression profiles. Transcriptomic analysis revealed over 4000 differentially expressed genes, with key disruptions identified in calcium signaling, MAPK signaling, cardiac muscle development, and vascular smooth muscle contraction pathways. These findings indicate that early salt exposure can perturb crucial developmental processes and signaling networks, offering insights into how prenatal environmental factors may contribute to long-term cardiovascular risk.