Methods for modulation of the effects of aging on the primate brain

DETAILED DESCRIPTION The invention provides a clinically useful protocol for delivery of recombinant nervous system growth factors into the aging mammalian brain.
The invention is particularly useful in tempering and reversing the loss of neurological function in the aging mammalian brain, by (a) correlating loss of cortical fiber density to impairment of neurological function in the normal, aging brain; and (b) providing means by which such losses may be reversed.
More specifically, the invention consists of methods for intraparenchymal delivery of a recombinant growth factor or other growth-promoting gene growth factor(generically, molecules which act on neuronal tissue to stimulate axonal growth) to the mammalian brain.
Delivery of the growth factors to targeted cells is achieved by in vivo transduction of neurons targeted for treatment, by transfection of cells neighboring these target neurons (neurons or glia) with a recombinant expression vector for expression of the desired growth factor in situ, and/or by ex vivo grafting of transgene expressing host cells to targeted tissue.
Growth factors delivered according to the invention exert a trophic effect at or near the delivery site (along chemotropic gradients stemming from the delivery site).
Startlingly, such growth factors also exert non-chemotropic effects on distant axonal termini.
Thus, the invention provides an opportunity to improve neuronal function over relatively expansive sectors of the brain while minimizing surgical invasion into brain tissue.