Effects of oxymatrine on the expression and release of high mobility group box 1 in pancreatic acinar cells stimulated by hydrogen peroxide

Abstract

Objective To observe the effects of oxymatrine(OM) on the expression and release of high mobility group box 1(HMGB1) in rat pancreatic acinar cell line AR42J stimulated by hydrogen peroxide. Methods MTT method was used to detect the effects of H2O2 in different concentrations on the survival of AR42J cells. AR42J cells cultured in vitro were divided into control group, H2O2 group and H2O2+ OM group. An equal volume of H2O2(final concentration 0.16 mmol/L) was added in H2O2 group and H2O2+ OM group, respectively, while an equal volume of triple distilled water was added in control group. In H2O2+ OM group, OM(final concentration 0.5 g/L)was added 0.5 h before the addition of H2O2, and cell samples and supernatant were collected after 24 h culture. The expression of HMGB1 protein was detected by Western blotting, the level of HMGB1 protein in cell supernatant was detected by enzyme-linked immunosorbent assay, and the intracellular distribution of HMGB1 protein was detected by immunofluorescence. Results In the H2O2 group, the expression of HMGB1, the secretion of HMGB1 in the supernatant and the proportion of cytoplasmic HMGB1 in the total HMGB1 were significantly higher than those in the control group[1.04±0.04 vs 0.69±0.02, (4.84±0.13)μg/L vs (2.68±0.07)μg/L, (35.7±2.5)% vs (10.7±1.9)%], and all the differences were statistically significant (all P<0.05). After OM intervention, HMGB1 protein expression, secretion and cytoplasmic proportion were [0.82±0.02, (3.97±0.10)μg/L and (27.3±1.7)%], respectively, which were obviously lower than those in the H2O2 group, and all the differences were statistically significant (all P<0.05). Conclusions H2O2 can induce the expression and release of HMGB1 in rat pancreatic acinar cells; OM treatment could alleviate the severity of oxidative stress injuries induced by H2O2 in AR42J cells. Key words: Pancreas; Oxymatrine; Hydrogen peroxide; Oxidative stress; High mobility group proteins