In primary-cultured rat stellate cells and the LX-2 human stellate cell line, induction of BMP-7 by Ad-BMP-7 infection decreased the expression of collagen 1A2 mRNA and smooth muscle & [alpha]-actin in the presence or absence of TGF-beta, via Smad1/5/8 phosphorylation. BMP-7 triggered the mRNA expression of inhibitors of differentiation 2 (Id2) in LX-2. Although endogenous expression of BMP-7 was hardly detectable, Smad1 and Id2 overexpression increased BMP-7 expression in LX-2. A liver fibrosis model was induced by the repetitive intraperitoneal injection of thioacetamide (200 mg/kg body weight) twice per week for up to 7 weeks. In rats that were received Ad-BMP-7 via tail vein, hydroxyproline content and the areas stained by Sirius red dye in the liver were significantly reduced compared to the controls. Furthermore, Ad-Id2 reduced fibrosis as well.
PMID: 17127702 (Gut)