Host: The Japanese Society of Toxicology
Name : The 51st Annual Meeting of the Japanese Society of Toxicology
Date : July 03, 2024 - July 05, 2024
Assessment of histopathological changes in the brain is essential for in vivo neurotoxicity testing. However, whole brain histological analysis is labor-intensive and costly. In this study, we have developed an efficient method for three-dimensional imaging of larval zebrafish brain exposed to neurotoxic compounds, enabling quantitative analysis of cell death and microglia dynamics. Zebrafish embryos were exposed to neurotoxic agents at multiple concentrations and durations up to 24 hours. For labeling, fluorescent dyes that can quickly stain structures such as white matter, cell membrane and dead cell throughout the body, and transgenic zebrafish that specifically express fluorescent proteins in microglia were used. The brains of the samples mounted on observation plate were scanned using a two-photon excitation microscope. Data such as the position and shapes of dead cells and microglia were automatically acquired from all images using an ImageJ macro. Additionally, qualitative evaluation of histological properties and the coordinates of specific brain region were obtained manually. Statistical analysis of the data was performed using R, adjusting for individual variations in body orientation and size based on coordinate data, which facilitated sample comparison. Variations in metrics representing cell count and morphology in each region of the brain result from differences in test compound, concentration, and exposure time. Our method streamlines the analysis of histological changes in the brain caused by neurotoxic substances.
