Accumulation of Lipofuscin in the Hippocampus of Mice under Various Nutritional Conditions During Aging

Abstract

The hippocampus of mice that had been on a high-fat diet for a long time (up to 12 months) was studied. The control group of animals received standard laboratory food. The object of the study was lipofuscin, an undegradable autofluorescent pigment that forms intracellular aggregates in the cytoplasm and lysosomes of long-lived postmitotic cells. Unlike proliferative cells, which effectively dilute the lipofuscin pool by dividing, neurons demonstrate its progressive accumulation, while cell transport and metabolism are violated, which contributes to the death of neurons and activation of glia. The results showed that age-related accumulation of lipofuscin was observed in all studied regions of the hippocampus during aging in animals on a standard diet. However, no such accumulation of lipofuscin was found in the granular neurons of the dentate fascia of the hippocampus in animals on a high-fat diet. The data obtained, in particular, the reduced lipofuscin content in the granular cells of the dentate gyrus during a prolonged high-fat diet, suggest that such a diet may activate compensatory or adaptive mechanisms in the hippocampus that prevent cellular aging.