Differential expression of advanced glycosylation end-products in neurons of different species.

The developmental time course and life span of the human brain are different from those of laboratory animals. These variations may be the reflection of metabolic differences of the neurons between different species. Using immunocytochemistry, we show that pyramidal neurons accumulate advanced glycosylation end products (AGEPs) formed by the Maillard reaction. However, the patterns of AGEPs accumulation in the pyramidal neuron were quite distinct between human and the 4 different animal species (horse, calf, pig, and rat) examined. In the human pyramidal neuron, AGEPs depict a granular, perikaryonal distribution, whereas in the animal brains, AGEPs show a nuclear staining pattern. The different patterns of AGEPs distribution in the pyramidal neurons suggest that AGEPs is an in vivo biochemical marker which distinguishes human pyramidal neurons from those of animals, and may help characterise pathologies specific to human.