Cell Culture to Investigate Neurotoxicity and Neurodegeneration Utilizing Caenorhabditis elegans

Abstract

Movement disorders such as Parkinson’s Disease (PD) result, in part, from the selective loss of dopaminergic (DA) neurons. Many studies associated with DA neurodegeneration and neurotoxicity have successfully applied the model organism Caenorhabditis elegans to address PD-related questions. However, some pharmacological studies might be limited because the thick cuticle of the intact animal could preclude complete penetration of some chemicals. It is also difficult to examine neurons within the same individual nematode, day after day, for studies of aging and neurodegeneration. More recently, methods for culturing embryonic cells from C. elegans have proved to be an alternative resource for addressing the caveats associated with whole nematode studies. In this regard, cultured embryonic C. elegans DA neurons differentiate following dissociation from early embryos. These cells adhere to culture dish surfaces that are covered with peanut lectin and subsequently differentiate into neurons. GFP-labeled DA neurons can then be followed over time and further manipulated to provide a means for examining cellular mechanisms associated with PD. For example, the DA neurons can be exposed to neurotoxins or, if the DA neurons also express a known PD gene that causes neurodegeneration, specific neurons can be scored for cumulative neurodegenerative changes on consecutive days. In contrast, control DA neurons have not been observed to undergo degenerative changes in culture. These methods have provided additional tools for exploring DA neurodegeneration in C. elegans, rendering primary neuronal cell culture as a complementary approach to whole nematode studies for examining neurodegeneration associated with PD.