ANG II-AT₁ receptor pathway is involved in the anti-fibrotic effect of β-elemene

Abstract

To investigate the effects of β-elemene on the ANG II-AT₁ receptor pathway in rats with liver fibrosis, a model of hepatic fibrosis was induced by hypodermical injection of carbon tetrachloride (CCl₄) into Wistar male rats. β-elemene was intraperitonealy administered into the rats for 8 weeks (0.1 mL/100 g body weight per day). Masson staining was used to observe the liver fibrosis of rats and liver functions were measured by enzymatic kinetic analysis. The content of hydroxyproline in liver tissues was detected by specimen alkaline hydrolysis. The level of plasma ANG in blood II plasma was detected by radioimmunoassay. The expression of AT₁R in rat liver were measured using reverse transcriptional-polymerase chain reaction and immunohistochemistry respectively. The results showed that β-elemene could reduce the collagen disposition in liver and inhibit the progression of liver fibrosis. In addition, the levels of plasma ANG II and the expression of hepatic AT₁R in rats with liver fibrosis were also suppressed by β-elemene. It is concluded that the ANG II-AT₁ receptor pathway plays an important role in the development of hepatic fibrosis and β-elemene could down-regulate the levels of plasma ANG II and the expression of hepatic AT₁R in rats with liver fibrosis.

Keywords

liver fibrosis / β-elemene / angiotensin II / AT₁ receptors

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