Glycyrrhizin down-regulates CCL2 and CXCL2 expression in cerulein-stimulated pancreatic acinar cells.

Many inflammatory chemokines release from leukocytes and pancreatic acinar cells which play important roles in pathophysiology of acute pancreatitis (AP). Of interests, CXCL2 and CCL2 have been shown elevated in the plasma of patients with AP. We have recently found that Glycyrrhizin (GZ) attenuates AP in mice model. In this study, we aimed to investigate the direct effect of GZ on expression levels of CCL2 and CXCl2 in isolated pancreatic acinar cells. Isolated acinar cells were isolated from the pancreas of healthy C57BL/6 mice, stimulated with cerulein (10(-7) M) and then treated with either PBS or different doses of GZ. The levels of CCL2 and CXCL2 expression at mRNA were assessed by qRT-PCR. Conditioned media from supernatants of each cells culture condition were collected for detection of CCL2 and CXCL2 levels by ELISA. First, we observed that cerulein significantly upregulates both cytokines expression in acinar cells. Moreover, we treated the acinar cells with GZ and found that GZ significantly downregulates CCL2 and CXCL2 expression at mRNA levels in a dose-dependent manner. Consistently, the conditioned media of GZ-treated cells contained a significant lower levels of CCL2 and CXCL2 (p<0.05). In conclusion, our data demonstrate for the first time that GZ directly downregulates CCL2 and CXCL2 levels in cerulein-stimulated acinar cells which may explain the mechanism of therapeutic effects of GZ in cerulein-induced AP in mice.