Multitargeted inhibition of hepatic fibrosis in chronic iron-overloaded mice by Salvia miltiorrhiza

Abstract

Ethnopharmacological relevance: Salvia miltiorrhiza (SM, also known as Danshen) is a well-known Chinese medicinal herb, which has shown hepatoprotective effects with anti-fibrotic, anti-oxidative, anti-inflammatory and anti-apoptotic properties. To explore the effects and potential mechanism of SM against hepatic fibrosis induced by chronic iron overload in mice.

Materials and methods: Sixty male mice were randomized into five groups (n=12 in each group): control (saline), iron overload, iron overload with low-dose SM (3g/kg/day), iron overload with high-dose SM (6g/kg/day) and iron overload with deferoxamine (100mg/kg/day) groups. The iron overload model was established by intraperitoneal injection with iron dextran at 50mg/kg body weight/day, and the entire course lasted for 7 weeks. The major constituents of SM injection were quantified by high performance liquid chromatography. Changes of hepatic iron, hydroxyproline (Hyp), glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) were assayed by standard procedures. Protein expression levels of type I collagen, type III collagen, tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1α) were analyzed by immunohistochemistry, and mRNA levels of transforming growth factor-β (TGF-β), matrix metal proteinase-9 (MMP-9) and caspase-3 were detected by RT-PCR. Morphological changes were observed with Prussian blue, Masson's trichrome and hematoxylin-eosin staining.

Results: Treatment of chronic iron-overloaded mice with SM dose-dependently ameliorated changes in hepatic morphology and coefficient, reduced iron deposition and Hyp content, suppressed overexpression of type I collagen and type III collagen, downregulated expression of TGF-β mRNA, and upregulated expression of MMP-9 mRNA in the liver. Moreover, SM treatment contributed to decreased MDA content, increased SOD activity and GSH content, while it reduced expression of TNF-α, IL-1α and caspase-3.

Conclusions: SM displayed anti-fibrotic activity in the liver induced by chronic iron overload, which may be attributed to multitargeted inhibition of iron deposition and collagen accumulation, as well as oxidative stress, inflammation and apoptosis.