Recent Advances in Studying Age-Associated Lipids Alterations and Dietary Interventions in Mammals

Abstract

Lipids are involved in a broad spectrum of canonical biological functions, from energy supply and storage by triacylglycerols to membrane formation by sphingolipids, phospholipids and glycolipids. Because of this wide range of functions, there is an overlap between age-associated processes and lipid pathways. Lipidome analysis revealed age-related changes in the lipid composition of various tissues in mice and humans, which were also influenced by diet and gender. Some changes in the lipid profile can be linked to the onset of age-related neurodegenerative diseases like Alzheimer's disease. Furthermore, the excessive accumulation of lipid storage organelles, lipid droplets, has significant implications for the development of inflammaging and non-communicable age-related diseases. Dietary interventions such as caloric restriction, time-restrictive eating, and lipid supplementation have been shown to improve pertinent health metrics or even extend life span and thus modulate aging processes.

Keywords: aging; dietary intervention; healthy life span; lipid; metabolism.

FIGURE 1

Schematic overview of lipid subclasses and connections to selected lipid metabolic pathways. Lipids are very diverse and complex biological compounds. The arrows illustrate similarities and connection between lipid categories, main classes, subclasses and substructures. Seven categories are shown that have been relevant in aging-associated studies. Examples for phospholipids and neutral lipids (as a subclass of glycerophospholipids) are shown in the left and middle box, respectively. The right box shows the simplified arachidonic cascade as example for the eicosanoid production from free fatty acids. Important lipid mediators that are known to be involved in inflammatory processes are shown in yellow. Abbreviations: PLA₂, phospholipase A₂; MUFA, monounsaturated fatty acid; PUFA, polyunsaturated fatty acid; DAGL, diacylglycerol lipase.