title: Low density lipoprotein receptor-related protein 1 modulates the proliferation and migration of human hepatic stellate cells.
abstract: Human hepatic stellate cells (HHSCs) proliferation and migration play a key role in the pathogenesis of liver inflammation and fibrogenesis. Low density lipoprotein receptor-related protein (LRP1) is an endocytic receptor involved in intracellular signal transduction. The aim of this work was to analyse the role of low density lipoprotein receptor-related protein (LRP1) in HHSCs proliferation and migration and the mechanisms involved. Human LRP1 deficient-HHSCs were generated by nucleofecting the line HHSCs with siRNA anti-LRP1. HHSCs DNA synthesis was measured by [(3) H]-thymidine incorporation and cell cycle progression by flow cytometry after annexin V and iodure propidium staining. Cell migration was assessed using a wound repair model system. LRP1 expression and extracellular matrix-regulated kinase (ERK1,2) phosphorylation were analysed by Western blot analysis. Transforming growth factor-β (TGF-β) extracellular levels were analysed by ELISA. siRNA-antiLRP1 treatment almost completely inhibited LRP1 mRNA and protein expression. LRP1 deficient HHSCs showed higher proliferative response (172 ± 19 vs. 93 ± 8 [(3) H]-thymidine incorporation; 78.68% vs. 82.69% in G0/G1, 21.32% vs. 17.30% in G2/S) and higher migration rates than control HHSCs. LRP1 deficient cells showed higher levels of phosphorylated ERK1,2. TGF-β extracellular levels were threefold higher in LRP1-deficient than in control HHSCs cells. These results demonstrate that LRP1 regulates HHSCs proliferation and migration through modulation of ERK1,2 phosphorylation and TGF-β extracellular levels. These results suggest that HHSCs-LRP1 may play a key role in the modulation of factors determining hepatic fibrosis.
authors.affiliation: Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-Sant Pau, Hospital de la Santa Creu I Sant Pau, Barcelona, Spain. cllorente@csic-iccc.org
authors.forename: V
authors.initials: V
authors.lastname: Llorente-Cortes
authors.forename: V
authors.initials: V
authors.lastname: Barbarigo
authors.forename: L
authors.initials: L
authors.lastname: Badimon
mesh_terms: D002453:Cell Cycle / Q000235:genetics; D048708:Cell Growth Processes / Q000235:genetics; D002465:Cell Movement / Q000235:genetics*; D002478:Cells, Cultured; D055166:Hepatic Stellate Cells / Q000166:cytology* / Q000378:metabolism*; D006801:Humans; D026503:Low Density Lipoprotein Receptor-Related Protein-1 / Q000235:genetics* / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000235:genetics; D010766:Phosphorylation; D012333:RNA, Messenger / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism
chemical_list: C475476:LRP1 protein, human; D026503:Low Density Lipoprotein Receptor-Related Protein-1; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta