SYP-3343 drives abnormal vascularization in zebrafish through regulating endothelial cell behavior

Area of Science:

• Toxicology
• Developmental Biology
• Molecular Biology

Background:

• Strobilurin fungicides like SYP-3343 exhibit broad antifungal activity but raise public health concerns due to potential toxicity.
• The specific vascular toxicity of SYP-3343 in developing organisms, such as zebrafish embryos, remains poorly understood.

Purpose of the Study:

• To investigate the effects of SYP-3343 on vascular development in zebrafish embryos.
• To elucidate the underlying mechanisms of SYP-3343-induced vascular toxicity.

Main Methods:

• Zebrafish embryo exposure to SYP-3343 and N-acetylcysteine (NAC).
• Assessment of vascular morphology, endothelial cell behavior (migration, sprouting), and nuclear morphology.
• RNA sequencing to analyze transcriptional changes in vascular development pathways.
• Human Umbilical Vein Endothelial Cell (HUVEC) assays to evaluate cytotoxicity, oxidative stress, mitochondrial function, cell cycle, and apoptosis.

Main Results:

• SYP-3343 inhibited zebrafish endothelial cell migration, induced abnormal vasculogenesis and angiogenesis, leading to angiodysplasia.
• RNA sequencing revealed significant alterations in genes related to angiogenesis, blood vessel morphogenesis, and vasculature development.
• SYP-3343 induced cytotoxicity in HUVECs, including impaired migration, disrupted cell cycle, mitochondrial dysfunction, increased reactive oxygen species (ROS), and apoptosis.
• NAC treatment ameliorated SYP-3343-induced vascular defects in zebrafish embryos.

Conclusions:

• SYP-3343 exhibits significant vascular toxicity in zebrafish embryos, mediated by disruption of endothelial cell function and developmental pathways.
• The fungicide induces cytotoxicity through oxidative stress, mitochondrial dysfunction, cell cycle arrest, and apoptosis, potentially involving p53 and caspase-3.
• These findings highlight the cytotoxic potential of SYP-3343 and suggest NAC as a potential counteragent for its vascular effects.