C3-induced release of neurotrophic factors from Schwann cells - potential mechanism behind its regeneration promoting activity

Unexpectedly, prolonged delivery of C3 and C3156−181 at the lesion site did not increase the outcome of PNR. Regarding the potential mechanism underlying their previously detected PNR promoting action, however, 6 genes were found to be commonly altered in SCs upon treatment with C3 or C3156−181. We demonstrate significant down-regulation of genes involved in glutamate uptake (Eaac1,5Grin2a6) and changes in neurotrophic factor expression (increase of FGF-27 and decrease of NGF8). Our microarray-based expression profiling revealed novel C3-regulated genes in SCs possibly involved in the axonotrophic (regeneration promoting) effects of C3 and C3156−181. Detection of altered neurotrophic factor expression by C3 or C3156−181 treated primary neonatal rat SCs and primary adult human SCs supports this hypothesis.