Large-scale in vivo femtosecond laser neurosurgery screen reveals small-molecule enhancer of regeneration

Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 10/2010; 107(43):18342-7. DOI: 10.1073/pnas.1005372107
Source: PubMed


Discovery of molecular mechanisms and chemical compounds that enhance neuronal regeneration can lead to development of therapeutics to combat nervous system injuries and neurodegenerative diseases. By combining high-throughput microfluidics and femtosecond laser microsurgery, we demonstrate for the first time large-scale in vivo screens for identification of compounds that affect neurite regeneration. We performed thousands of microsurgeries at single-axon precision in the nematode Caenorhabditis elegans at a rate of 20 seconds per animal. Following surgeries, we exposed the animals to a hand-curated library of approximately one hundred small molecules and identified chemicals that significantly alter neurite regeneration. In particular, we found that the PKC kinase inhibitor staurosporine strongly modulates regeneration in a concentration- and neuronal type-specific manner. Two structurally unrelated PKC inhibitors produce similar effects. We further show that regeneration is significantly enhanced by the PKC activator prostratin.

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    • "Thus, it is a challenging task to monitor the gas-evoked neuronal activities in an immobilized worm for sensory biology investigations. As an alternative, microfluidic technologies have shown great potential for manipulating this small freely moving animal and providing a precisely controlled dynamic environment for high spatiotemporal resolution imaging [9] [10] [11] [12] [13]. Various microfluidic systems have been developed for greatly facilitating the study of the nematode's sensorial ability in detecting a wide range of water-soluble chemical cues [14] [15] [16] [17] [18] [19]. "
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