The glycoprotein (18 kDa) isolated from Lactobacillus plantarum L67 suppressed ß-hexosaminidase, histamine, and the expression of TNF-α and IL-4 in the BPA-stimulated RBL-2H3 cells

• L67 protein inhibited the allergic markers (degranulation and histamine release) in BPA-treated RBL-2H3 cells.
• L67 protein suppressed the expression of allergic relative cytokines (TNFα, IL-4).
• L67 protein might have a character to prevent allergic diseases.

This study investigated the inhibitory effect of the 18 kDa glycoprotein isolated from Lactobacillus plantarum L67 on the bisphenol A-mediated inflammatory reaction in RBL-2H3 cells. The RBL-2H3 cells were treated with bisphenol A (50 μmol) and the glycoprotein isolated from L. plantarum L67 (5–100 μg/ml) for 30 min. Subsequently, the release of histamine and β-hexosaminidase into the medium and the intracellular Ca2+ levels were measured. The activities of PKC and iNOS were measured by western blotting. In addition, the gene expression levels of IL-4 and TNF-α were measured by qRT-PCR. In conclusion, the results demonstrated that the degranulation of the BPA-stimulated RBL-2H3 cells and their histamine release were inhibited by the glycoprotein of L. plantarum L67; concurrently, the levels of intracellular Ca2+, the activity of iNOS, and the expression of TNF-α and IL-4, two allergy-related cytokines, were also suppressed by the glycoprotein. Taken together, these results indicate that the glycoprotein might help to prevent allergic diseases induced by environmental hormones, such as BPA.

Proposed mechanism of L67 protein anti-allergic activity in BPA-stimulated RBL-2H3 cells; → indicates induction ⊥indicates repression.At co-treatment with BPA, the allergic factors and signals (degranulation, histamine releasing, Ca2+ level, PKC translocation, gene expression of IL-4 and TNF-α) were definitely changed upon L67 protein in 30 min.Proposed mechanism of L67 protein anti-allergic activity in BPA-stimulated RBL-2H3 cells; → indicates induction ⊥indicates repression.At co-treatment with BPA, the allergic factors and signals (degranulation, histamine releasing, Ca2+ level, PKC translocation, gene expression of IL-4 and TNF-α) were definitely changed upon L67 protein in 30 min.Figure optionsDownload as PowerPoint slide