Amelioration of liver fibrogenesis by dual inhibition of PDGF and TGF-β with a combination of imatinib mesylate and ACE inhibitor in rats

Abstract

Both platelet-derived growth factor (PDGF) and transforming growth factor-β (TGF-β) are known to be pivotal cytokines in liver fibrosis development. The aim of our current study was to elucidate the effects of dual inhibition of PDGF and TGF-β by combination of the clinically used imatinib mesylate (STI-571) and perindopril (an ACE-inhibitor; ACE-I), respectively, on ongoing liver fibrosis development in rats. The effects of STI-571 and ACE-I at clinically comparable low doses were examined in a rat model of CCl4-induced liver fibrogenesis. Treatment with both STI-571 and ACE-I inhibited liver fibrogenesis and suppressed activation of hepatic stellate cells (HSCs). Administration of both agents exerted a more potent inhibitory effect than administration of either single agent. Our in vitro study demonstrated that STI-571 and ACE-I suppressed PDGF receptor (PDGFR) phosphorylation and TGF-β expression in activated HSCs, respectively. Dual suppression of PDGF and TGF-β with a combination of clinically comparable low doses of STI-571 and ACE-I exerted a significant inhibitory effect on ongoing liver fibrosis development. Since both agents are widely used in clinical practice, this combination therapy may provide a new strategy against liver fibrosis in the future.