Neuroprotection and aging of the cholinergic system: a role for the ergoline derivative nicergoline (Sermion).

The aging brain is characterized by selective neurochemical changes involving several neural populations. A deficit in the cholinergic system of the basal forebrain is thought to contribute to the development of cognitive symptoms of dementia. Attempts to prevent age-associated cholinergic vulnerability and deterioration therefore represent a crucial point for pharmacotherapy in the elderly. In this paper we provide evidence for the protective effect of nicergoline (Sermion) on the degeneration of cholinergic neurons induced by nerve growth factor deprivation. Nerve growth factor deprivation was induced by colchicine administration in rats 13 and 18 months old. Colchicine induces a rapid and substantial down-regulation of choline acetyltransferase messenger RNA level in the basal forebrain in untreated adult, middle-aged and old rats. Colchicine failed to cause these effects in old rats treated for 120 days with nicergoline 10 mg/kg/day, orally. Moreover, a concomitant increase of both nerve growth factor and brain-derived neurotrophic factor content was measured in the basal forebrain of old, nicergoline-treated rats. Additionally, the level of messenger RNA for the brain isoform of nitric oxide synthase in neurons of the basal forebrain was also increased in these animals. Based on the present findings, nicergoline proved to be an effective drug for preventing neuronal vulnerability due to experimentally induced nerve growth factor deprivation.