Basic fibroblast growth factor prevents cAMP-induced apoptosis in cultured Schwann cells

Peripheral nerve axotomy induces apoptosis in Schwann cell precursors; basic fibroblast growth factor (bFGF) protects these cells from axotomy-induced apoptosis (Jessen et al.: Neuron 12:509-527, 1994; Gavrilovic et al.: Eur J Neurosci 7:7-85, 1995). In this study, we investigate the effects of bFGF on apoptosis in neuron-free cultures of neonatal rat Schwann cells. Apoptotic cell death was induced in primary and secondary expanded Schwann cells by treatment with 1 mM concentrations of 8-bromoadenosine 3':5'-cyclic monophosphate (8-bromo-cAMP), a membrane-permeable analogue of cAMP which induces expression of galactocerebroside in the plasma membranes of Schwann cells. Treatment with bFGF reduced the percentage of galactocerebroside-bearing Schwann cells undergoing cAMP-induced DNA fragmentation. These findings suggest that bFGF can enhance the survival of terminally differentiated Schwann cells by preventing apoptosis.