Ginsenoside Rg1 protects mouse liver against ischemia-reperfusion injury through anti-inflammatory and anti-apoptosis properties

Abstract

Background: Ginsenoside Rg1, the major effective component of ginseng, possesses a variety of pharmacologic activities. The objective of this study was to investigate the effects of Rg1 on liver ischemia-reperfusion (IR) injury and explore its potential mechanisms.

Materials and methods: Liver warm IR injury was achieved by occluding the portal vein and hepatic artery for 1 h followed by 6-h reperfusion. Eighteen mice were equally randomized into three groups: sham group, IR group, and IR plus Rg1 group (n = 6 mice per group). Mice received an intravenous dose of 20 mg/kg Rg1 or an equivalent volume of saline before ischemic insult. Liver samples and serum were collected for analyses. Serum aminotransferase, histopathology, and apoptosis were determined. Cytokines were measured by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The phosphorylation of nuclear factor kappa B (NF-κB) p65 was assessed by Western blotting. In addition, the effect of Rg1 in a simulated IR model in vitro was also investigated. Rg1 (100 ug/mL and 500 ug/mL) was administered 1 h before hypoxia insult, and then apoptosis was measured after 12-h reperfusion.

Results: Liver IR injury led to a dramatic increase in aminopherase activity, apoptosis and necrosis of hepatocytes, and production of proinflammatory cytokines. Pretreatment with Rg1 protected mice from IR-induced liver injury. Treatment with a high-dose Rg1 (500 ug/mL) significantly suppressed apoptosis compared with a lower dose or control (both P < 0.001). Phosphorylation of NF-κB p65 was increased significantly in IR group, and administration with Rg1 suppressed the level of phosphorylation.

Conclusions: Pretreatment of mice with Rg1 reduced hepatocellular apoptosis and inhibited inflammatory response, which was in part through the NF-κB signaling pathway. Rg1 may provide a novel therapeutic strategy for the treatment of IR-induced liver injury.

Keywords: Apoptosis; Ginsenoside Rg1; Inflammation; Liver ischemia reperfusion injury.