The Neuritogenic Effect of Gangliosides in Cell Culture

Abstract

Gangliosides have long been suspected of playing a key role in neuronal differentiation, owing in part to the striking changes in concentration and pattern that have been shown to occur in vivo (for review: Ledeen, 1983). The same phenomenon has been observed in vitro, e.g. with primary neuronal cultures from 8-day-old chick embryonic brain (Dreyfus et al, 1980). The endogenous gangliosides of these neurons showed two discrete phases: the first involving cell division, in which ganglioside content increased only slightly while retaining a relatively simple pattern, and a second corresponding to cell maturation in which total content increased markedly due to appearance and rapid accumulation of ganglio-type structures*. Similar observations have been made with primary neuronal cultures from fetal rat hippocampus (Seifert and Fink, 1984). The discovery that exogenously administered gangliosides have neuritogenic and neuronotrophic properties, capable of influencing neuronal differentiation in vitro and neuronal repair in vivo (for review: Ledeen, 1984) has provided new paradigms for studying this aspect of ganglioside function. One approach to the general question of mechanism is to study the effects of structural variation, i.e. the range of gangliosides and ganglioside-related structures that produce neuritogenesis in culture. We report here initial findings in which we employed primarily neuroblastoma cells as the test system.