Platelet-derived growth factor-D intensifies fibrogenesis through upregulation of TIMP-1 expression and signalling through both platelet-derived growth factor receptors type α and β

Background: Platelet-derived growth factor-D (PDGF-D) is a more recent recognized growth factor of the PDGF family [1]. It regulates several cellular processes including cell proliferation, transformation, invasion, and angiogenesis through specifically binding to and activating its cognate receptor PDGFR-β. In experimental liver fibrotic models (BDL and carbon tetrachloride), we have shown that PDGF-D is upregulated comparable to that of PDGF-B [2, 3]. Moreover, adenoviral expression of PDGF-D induces hepatic stellate cell (HSC) proliferation and liver fibrosis [4]. We now seek to investigate the molecular mechanism of PDGF-D involvement in liver fibrogenesis.