Seabuckthorn berry polysaccharide extracts protect against acetaminophen induced hepatotoxicity in mice via activating the Nrf-2/HO-1-SOD-2 signaling pathway

Phytomedicine. 2018 Jan 1:38:90-97. doi: 10.1016/j.phymed.2017.11.007. Epub 2017 Nov 14.

Abstract

Background: Oxidative stress is concomitant with acetaminophen (APAP)-induced hepatotoxicity, which has been highlighted as therapeutic targets for such diseases. The berries of Seabuckthorn (Hippophae rhamnoides L.) have been traditionally used in Tibetan medicine for thousands of years. The effect of Seabuckthorn berry polysaccharide on drug- induced liver injury (DILI) has not yet been elucidated.

Purpose: This study aims to investigate the protective effects and mechanisms of Seabuckthorn polysaccharide (SP) against APAP-induced hepatotoxicity.

Study design: Sixty C57BL/6 mice were randomly divided into six groups (n = 10 per group), namely the control group (Ctrl), APAP-induced-liver injury group (APAP), NAC pretreated group (NAC), 100 mg/kg SP pretreated group (APAP/SP100), 200 mg/kg SP pretreated group (APAP/SP200) and 200 mg/kg SP pretreated group without APAP challenge (SP200). SP was given orally to mice for 30 consecutive days prior to APAP exposure (300 mg/kg). NAC (150 mg/kg) was administrated 1 h before APAP challenge.

Methods: ALT and AST were detected 16 h after APAP treatment; Hepatic expression of GSH, SOD, NO, iNOS and GSH-Px were examined. The expression of p-JNK, Bcl-2/Bax, p62, Keap-1 and SOD-2 was detected by Western blotting. The expression of Nrf-2 and its target genes HO-1, GCLC and NQO-1 were analyzed by RT-PCR and Western blotting.

Results: Pretreatment with SP led to decreased levels of ALT and AST in APAP mice, without affecting APAP metabolism. This was accompanied by diminished liver injuries, increased levels of GSH and GSH-Px, reduced NO and iNOS expression. SP increased the activity of SOD as well as SOD-2 expression in APAP mice. SP suppressed APAP-induced JNK phosphorylation and increased the ratio of Bcl-2/Bax. Furthermore, SP decreased the expression of Keap-1 and increased the nuclear expression of Nrf-2. The expression of Nrf-2 target gene HO-1 was increased by SP pretreatment in APAP mice.

Conclusion: SP alleviates APAP-induced hepatotoxicity. The protective effects of SP are associated with the activation of the Nrf-2/HO-1-SOD-2 signaling pathway.

Keywords: Acetaminophen; HO-1; Nrf-2; Oxidative stress; SOD-2; Seabuckthorn berry polysaccharide extracts.

MeSH terms

  • Acetaminophen / adverse effects*
  • Animals
  • Chemical and Drug Induced Liver Injury / metabolism
  • Chemical and Drug Induced Liver Injury / prevention & control*
  • Fruit / chemistry
  • Glutathione / metabolism
  • Heme Oxygenase-1 / metabolism
  • Hippophae / chemistry*
  • Liver / drug effects
  • Liver / metabolism
  • Liver / pathology
  • Male
  • Membrane Proteins / metabolism
  • Mice, Inbred C57BL
  • NF-E2-Related Factor 2 / metabolism
  • Nitric Oxide Synthase Type II / metabolism
  • Plant Extracts / chemistry
  • Polysaccharides / pharmacology*
  • Protective Agents / pharmacology*
  • Signal Transduction / drug effects
  • Superoxide Dismutase / metabolism

Substances

  • Membrane Proteins
  • NF-E2-Related Factor 2
  • Nfe2l2 protein, mouse
  • Plant Extracts
  • Polysaccharides
  • Protective Agents
  • Acetaminophen
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Heme Oxygenase-1
  • Hmox1 protein, mouse
  • Superoxide Dismutase
  • superoxide dismutase 2
  • Glutathione