Changes in the concentration and composition of human brain gangliosides with aging.

Ganglioside content and composition were studied in whole brains from 9 neurologically normal male individuals ranging from 25 to 85 years in age. The content of ganglioside-bound sialic acid decreased from 1,070 to 380 micrograms/g fresh tissue at 85 years. Ten individual ganglioside fractions were identified on high-performance thin-layer chromatography, seven of which were quantified. With age, ganglioside composition shifted to a more polar pattern due to an increase in the relative concentration of the more polar fractions GQ1b, GT1b and GD1b and a decrease in GD1a and GM1. Except for GQ1b, the absolute concentration of all gangliosides decreased with age. All changes were more pronounced in younger ages. Results are discussed in relation to structural changes occurring in the aging brain, and the involvement of gangliosides is suggested.