Enhancement of neuronal regeneration by optogenetic cellular activation in C. elegans

Large numbers of people suffer from nervous system injuries and neurodegenerative diseases each year, with little success in regaining lost neural functions. Attempts to successfully regenerate nervous tissue in the mammalian Central Nervous System have meet with limited success. Simpler models have thus been useful in determining conserved mechanisms in the enhancement of neural regeneration. One such mechanism is intracellular calcium signaling. We used Caenorhabditis elegans as a model system to study the effects of optogenetic stimulation on regeneration. Using a femtosecond laser we cut individual C. elegans axons in vivo and then periodically stimulated the neurons by activating the genetically encoded light activated channel, Channelrodopsin-2. We found that periodic photo-activation could increase regeneration over 24h by at least 31%. We repeated these experiments with dantrolene treatment and in unc-68(e540) mutants to assess the effects from a lack of internal calcium ion