Protective effect of cornel iridoid glycoside in D-galactosamine/tumor necrosis factor-α-injured L02 hepatocytes and its mechanism

J Intercult Ethnopharmacol. 2014 Oct-Dec;3(4):201-5. doi: 10.5455/jice.20140916011549. Epub 2014 Sep 27.

Abstract

Aim: The aim was to determine the action mode of cornel iridoid glycoside (CIG) from Fructus corni on hepatoprotective activities, the effects of CIG on human hepatocyte cell line (L02) injured by D-galactosamine (GalN) and tumor necrosis factor-α (TNF-α) were examined.

Materials and methods: The percentage of cell viability was evaluated by cell counting kit-8 assay. Apoptosis was detected by flow cytometric analysis in human L02 hepatocytes. The expression levels of activating transcription factor-4 (ATF4), and C/EBP homologous protein (CHOP) were detected by western-blot analysis. In addition, the activity of caspase-3 was tested by enzyme-linked immunosorbent assay.

Results: The results showed that CIG caused a significant increase in the viability of L02 cells injured by GalN/TNF-α, in accordance with a dose-dependent decrease of apoptotic cell death confirmed by flow cytometric analysis. Based on western blot and colorimetric assay, we found that GalN/TNF-α induced increased expression of ATF4, CHOP, and activation of caspase-3 while CIG pre-treatment had a dose-dependent suppression on them in this cell model.

Conclusion: Overall, these findings demonstrate that CIG can effectively protect L02 hepatocytes against apoptosis induced by GalN/TNF-α, suggesting that it is a possible candidate target for liver disease therapy.

Keywords: Apoptosis; D-galactosamine/tumor necrosis factor-α; L02 hepatocyte; cornel iridoid glycoside.