Sulfated Astragalus polysaccharide can regulate the inflammatory reaction induced by LPS in Caco2 cells

Abstract

This study evaluates the effect of sulfated Astragalus polysaccharide (SAPS) on inflammatory reaction induced by LPS in Caco2 cells. Sulfated modification was conducted using the chlorosulfonic acid–pyridine method. Caco2 cells were cultured with 25, 50 and 100μg/mL SAPS or 100μg/mL Astragalus polysaccharide (APS) for 24h. Then, 1μg/mL LPS was added for the next 24h to trigger an inflammatory response. DMEM culture medium was used as a blank control. In present study, LPS stimulation significantly increased the mRNA expression of TNF-α, IL-1β, IL-8 and TLR4, and reduced the expression of ZO-1 and occludin. Compared with the LPS control group, APS (100μg/mL) or SAPS (100μg/mL) administration decreased the expression of TNF-α, IL-1β and IL-8. Moreover, 25μg/mL and 50μg/mL SAPS down-regulated TNF-α and IL-1β expression. APS administration (100μg/mL) up-regulated occludin expression, but did not affect ZO-1 expression. However, the expression of ZO-1 and occludin was up-regulated by lower dose SAPS administration (25μg/mL and 50μg/mL). Compared with the other groups, the expression of TLR4 was lower in the SAPS group at all concentrations of SAPS. These results suggest that SAPS was to be a more effective anti-inflammatory agent than APS in vitro.