Abstract
Aging and neuronal deterioration constitute important risk factors for the development of neuronal-related diseases, such as different dementia. The nematode Caenorhabditis elegans has emerged as a popular model system for studying neurodegeneration diseases, due to its complete neuronal connectivity map. DiI is a red fluorescent dye that can fill the worm amphid neurons and enables the visualization of their neurodegeneration over time. This protocol provides an efficient, fast, and safe method to stain worm amphid neurons to highlight the chemosensory structures of live nematodes.