THE CONCEPT OF ASTROCYTE-KINETIC DRUG IN THE TREATMENT OF NEURODEGENERATIVE DISEASES - EVIDENCE FOR L-DEPRENYL-INDUCED ACTIVATION OF REACTIVE ASTROCYTES

Basic fibroblast growth factor (bFGF) increases neuronal survival and growth in cell cultures and stimulates functional recovery From brain lesion. In addition, bFGF is able to induce glial cell proliferation a nd differentiation. Recently, L-deprenyl has been shown to potentiate astrocyte reaction to a mechanical lesion and to possess a trophic-lik e activity in several experimental models. In the present paper, we ha ve therefore investigated if the enhancing effect of L-deprenyl on ast rocyte reactivity is accompanied by increased levels of bFGF. The effe ct of L-deprenyl (0.25 mg/kg/day) on bFGF immunoreactivity (IR) after the insertion of an injection cannula in rat neostriatum have been inv estigated. It has been found that subchronic L-deprenyl treatment pote ntiates both the lesion-induced increase of glial fibrillary acidic pr otein (GFAP) and bFGF IRs (P < 0.01). These data suggest that a possib le mechanism for L-deprenyl-induced neuroprotection may be the activat ion of astrocytes associated with increased secretion of trophic facto rs that promote neuronal survival and growth. This ''astrocyte-kinetic '' action of L-deprenyl could represent a new therapeutical approach t o increase trophic support of lesioned neurons.