Lipidlager

Lipidlager refers to stores of neutral lipids in organisms. In Swedish usage it describes lipid storage both at the cellular level and in adipose tissue. The main lipid components are triglycerides and cholesterol esters, which can be mobilized to supply energy when needed.

In cells, neutral lipids accumulate as lipid droplets, organelles with a hydrophobic core of triglycerides and cholesterol esters surrounded by a phospholipid monolayer and a coat of proteins such as perilipins. Droplets form in the endoplasmic reticulum and can be mobilized by lipolytic enzymes.

Adipose tissue stores large amounts of triglycerides in adipocytes, which expand through lipid uptake and adipogenesis. During fasting, lipolysis releases fatty acids to supply energy, while glycerol can feed gluconeogenesis. Key enzymes include ATGL, HSL and MGL, coordinated by hormonal signals such as insulin and catecholamines.

Regulation and health relevance: lipidlager function is central to energy homeostasis. Excess or deficient lipid storage is linked to metabolic diseases such as obesity, insulin resistance and lipodystrophy. Ectopic accumulation of lipids in liver or muscle can contribute to non-alcoholic fatty liver disease and impaired glucose tolerance.

Research and perspectives: lipidlager dynamics involve lipid droplet biogenesis, growth and degradation, lipid droplet–ER contacts, and lipophagy. Proteomic studies identify numerous associated proteins that regulate storage and mobilization, highlighting lipidlager as an active component of cellular metabolism and disease.