Inhibitory effect of Styrax Japonica Siebold et al. Zuccarini glycoprotein (38 kDa) on interleukin-1β and induction proteins in chromium(VI)-treated BNL CL.2 cells

Abstract

Chromium(VI) [Cr(VI)] induces chronic inflammation in hepatocytes. Inflammation has been shown to play an important role in tumorigenesis, tumor progression, and metastasis. To examine the effects of the Styrax Japonica Siebold et al. Zuccarini (SJSZ) glycoprotein on inflammation in BNL CL.2 cells, we evaluated the activities of c-Jun NH(2)-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), nuclear factor (NF)-κB (p50 and p65), and inflammation-related factors [cyclooxygenase (COX)-2, inducible nitric oxide syntheses (iNOS) and interleukin (IL)-1β] in Cr-induced BNL CL.2 cells using immunoblot analysis and RT-PCR. We also used two-dimensional gel electrophoresis (2-DE) to compare between treatments. To determine which proteins are induced by Cr(VI), we evaluated total protein lysates using 2-DE. After Cr(VI) treatment, total protein lysates were prepared and resolved by 2-DE. The results obtained from this study demonstrated that the SJSZ glycoprotein (50μg/ml) inhibits expression of JNK, ERK, NF-κB, and the expression of COX-2, iNOS, and IL-1β. Moreover, the results obtained from 2DE showed that four proteins out of nine proteins were relatively expressed strongly, while the rest of them were relatively appeared weakly on the gel. Taken together, these data indicate that the SJSZ glycoprotein prevents expression of COX-2, iNOS, and IL-1β by blocking NF-κB and MAPKs in Cr(VI)-induced BNL CL.2 cells.