| First Author | Frey E | Year | 2015 |
| Journal | Exp Neurol | Volume | 263 |
| Pages | 350-63 | PubMed ID | 25447942 |
| Mgi Jnum | J:218775 | Mgi Id | MGI:5618374 |
| Doi | 10.1016/j.expneurol.2014.10.012 | Citation | Frey E, et al. (2015) An in vitro assay to study induction of the regenerative state in sensory neurons. Exp Neurol 263:350-63 |
| abstractText | After injury, peripheral neurons activate a pro-regenerative program that facilitates axon regeneration. While many regeneration-associated genes have been identified, the mechanism by which injury activates this program is less well understood. Furthermore, identifying pharmacological methods to induce a pro-regenerative state could lead to novel treatments to repair the injured nervous system. Therefore, we have developed an in vitro assay to study induction of the pro-regenerative state following injury or pharmacological treatment. First, we took advantage of the observation that dissociating and culturing sensory neurons from dorsal root ganglia activates a pro-regenerative program. We show that cultured neurons activate transcription factors and upregulate regeneration-associated genes common to the pro-regenerative program within the first hours after dissection. In a paradigm similar to pre-conditioning, neurons injured by dissociation display enhanced neurite outgrowth when replated as early as 12h after being removed from the animal. Furthermore, stimulation of the pro-regenerative state improves growth on inhibitory substrates and requires DLK/JNK signaling, both hallmarks of the pro-regeneration response in vivo. Finally, we modified this assay in order to identify new methods to activate the pro-regenerative state in an effort to mimic the pre-conditioning effect. We report that after several days in culture, neurons down-regulate many molecular hallmarks of injury and no longer display enhanced neurite outgrowth after replating. Hence, these neurons are functionally naive and are a useful tool for identifying methods to induce the pro-regenerative state. We show that both injury and pre-treatment with forskolin reactivate the pro-regenerative state in this paradigm. Hence, this assay is useful for identifying pharmacological agents that induce the pro-regenerative state in the absence of injury. |
