Early activation of hepatic stellate cells induces rapid initiation of retinyl ester breakdown while maintaining lecithin:retinol acyltransferase (LRAT) activity.

Lecithin:retinol acyltransferase (LRAT) is the main enzyme producing retinyl esters (REs) in quiescent hepatic stellate cells (HSCs). When cultured on stiff plastic culture plates, quiescent HSCs activate and lose their RE stores in a process similar to that in the liver following tissue damage, leading to fibrosis. Here we validated HSC cultures in soft gels to study RE metabolism in stable quiescent HSCs and investigated RE synthesis and breakdown in activating HSCs.

Lipidomic profiling of rat hepatic stellate cells during activation reveals a two-stage process accompanied by increased levels of lysosomal lipids.

Hepatic stellate cells (HSCs) are liver-resident cells best known for their role in vitamin A storage under physiological conditions. Upon liver injury, HSCs activate into myofibroblast-like cells, a key process in the onset of liver fibrosis. Lipids play an important role during HSC activation.

Retinyl esters form lipid droplets independently of triacylglycerol and seipin.

Lipid droplets store neutral lipids, primarily triacylglycerol and steryl esters. Seipin plays a role in lipid droplet biogenesis and is thought to determine the site of lipid droplet biogenesis and the size of newly formed lipid droplets. Here we show a seipin-independent pathway of lipid droplet biogenesis.

Retinoids in health and disease: A role for hepatic stellate cells in affecting retinoid levels.

Vitamin A (retinol) is important for normal growth, vision and reproduction. It has a role in the immune response and the development of metabolic syndrome. Most of the retinol present in the body is stored as retinyl esters within lipid droplets in hepatic stellate cells (HSCs).

Identification of potential drugs for treatment of hepatic lipidosis in cats using an in vitro feline liver organoid system.

Background: Hepatic lipidosis is increasing in incidence in the Western world, with cats being particularly sensitive. When cats stop eating and start utilizing their fat reserves, free fatty acids (FFAs) increase in blood, causing an accumulation of triacylglycerol (TAG) in the liver.

Objective: Identifying potential new drugs that can be used to treat hepatic lipidosis in cats using a feline hepatic organoid system.