Kyritsis, N., Kizil, C., Zocher, S., Kroehne, V., Kaslin, J., Freudenreich, D., Iltzsche, A., and Brand, M. (2012) Acute Inflammation Initiates the Regenerative Response in the Adult Zebrafish Brain. Science (New York, N.Y.). 338(6112):1353-1356.
The zebrafish regenerates its brain after injury and hence is a useful model organism to study the mechanisms enabling regenerative
neurogenesis, which is poorly manifested in mammals. Yet, the signaling mechanisms initiating such a regenerative response
in fish are unknown. Using cerebroventricular microinjection of immunogenic particles and immunosuppression assays, we show
that inflammation is required and sufficient for enhancing the proliferation of neural progenitors and subsequent neurogenesis
by activating injury-induced molecular programs that can be observed after traumatic brain injury. We also identified the
cysteinyl leukotriene signaling as an essential component of inflammation on the regenerative process of the adult zebrafish
brain. Thus, our results demonstrate that in zebrafish—in contrast to mammals—inflammation is a positive regulator of neuronal
regeneration in the central nervous system.