title: Expression of carboxylesterase and lipase genes in rat liver cell-types.
abstract: Approximately 80% of the body vitamin A is stored in liver stellate cells with in the lipid droplets as retinyl esters. In low vitamin A status or after liver injury, stellate cells are depleted of the stored retinyl esters by their hydrolysis to retinol. However, the identity of retinyl ester hydrolase(s) expressed in stellate cells is unknown. The expression of carboxylesterase and lipase genes in purified liver cell-types was investigated by real-time PCR. We found that six carboxylesterase and hepatic lipase genes were expressed in hepatocytes. Adipose triglyceride lipase was expressed in Kupffer cells, stellate cells and endothelial cells. Lipoprotein lipase expression was detected in Kupffer cells and stellate cells. As a function of stellate cell activation, expression of adipose triglyceride lipase decreased by twofold and lipoprotein lipase increased by 32-fold suggesting that it may play a role in retinol ester hydrolysis during stellate cell activation.
authors.affiliation: Gastroenterology Unit, Department of Clinical Pathophysiology, University of Florence, Florence, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Mello
authors.forename: Alice
authors.initials: A
authors.lastname: Nakatsuka
authors.forename: Sharry
authors.initials: S
authors.lastname: Fears
authors.forename: Wilhelmina
authors.initials: W
authors.lastname: Davis
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Tsukamoto
authors.forename: William F
authors.initials: WF
authors.lastname: Bosron
authors.forename: Sonal P
authors.initials: SP
authors.lastname: Sanghani
mesh_terms: D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000235:genetics*; D002469:Cell Separation; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000201:enzymology; D015870:Gene Expression; D022781:Hepatocytes / Q000201:enzymology*; D007728:Kupffer Cells / Q000201:enzymology; D008049:Lipase / Q000235:genetics*; D008071:Lipoprotein Lipase / Q000235:genetics; D008099:Liver / Q000166:cytology / Q000201:enzymology*; D016133:Polymerase Chain Reaction; D051381:Rats; D014801:Vitamin A / Q000378:metabolism*
chemical_list: D014801:Vitamin A; D002265:Carboxylic Ester Hydrolases; C022523:retinyl esterase; D008049:Lipase; D008071:Lipoprotein Lipase