Primary cultures of mouse HSC were activated in response to culture on plastic, marked by increased expression of alpha smooth muscle actin (αSMA) and collagen 1A1 (Col1A1) mRNA. Expression of mRNA and protein for the C5aR also increased during HSC activation in culture. To study if C5aR expression also increased during in vivo activation of HSC, hepatic fibrosis was induced in mice expressing GFP under the control of the collagen promoter by exposure to carbon tetrachloride. FACS analysis of GFP expressing HSC revealed an increased expression of C5aR, similar to that observed

in HSC activated in culture. To understand the functional significance of C5aR expression in activated HSC activation, we next investigated whether C5a influenced HSC activation or migration. Challenge of HSCs with C5a during culture had no effect on expression of αSMA and Col1A1, suggesting that C5a did selleck chemicals llc not influence HSC activation. Another important characteristic of HSC is their migratory capacity, primarily mediated by the chemokine MCP-1 and platelet derived growth factor (PDGF). Since C5a is a potent chemokine, we hypothesized that C5a would Lumacaftor molecular weight stimulate HSC migration. To test this hypothesis, wound healing cell migration assay was carried out. C5a enhanced HSC migration almost as efficiently as PDGF. C5a also stimulated the expression of MCP-1. C5a-induced cell migration was slower, but not completely inhibited, in presence of 227016, an MCP-1

receptor antagonist, suggesting C5a-induced migration occurs via MCP-1 dependent and independent mechanisms. Furthermore, C5a did not increase Ki67 nuclear staining, indicating wound healing was independent of cell proliferation. Taken together, these data reveal a novel mechanism for the interaction between complement and hepatic fibrosis, and suggest that C5a and its receptors are possible therapeutic targets in the treatment of liver fibrosis. PAK6 Disclosures: The following people have nothing to disclose: Dola Das, Jazmine Danner, Mark A. Barnes, Laura E. Nagy Hepatic fibrosis represents

the most worrisome histopathologic feature in non-alcoholic steatohepatitis (NASH) and it suggests a more severe and progressive liver damage. Understanding the mechanisms linking NASH to fibrogenesis is essential for defining potential novel therapeutic strategies. We have recently demonstrated (EASL 2013) that hepatocyte-derived microparticles (MPs) are released in the bloodstream during experimental NASH and their levels strongly correlate with severity of liver fibrosis. Here we tested the hypothesis that MPs released by hepatocytes during lipotoxicity alters hepatic stellate cells (HSC) biology resulting in its activation. Methods. For induction of lipotoxicity, the human hepatoma cells (HepG2) were treated with a saturated free fatty acids (FFA) including palmitic acid, or stearic acid, for up to 24hrs with various concentrations (0.25 to 0.50 mM).