Acanthopanax senticosus polysaccharides-induced intestinal tight junction injury alleviation via inhibition of NF-κB/MLCK pathway in a mouse endotoxemia model

摘要

AIM To examine the effects of Acanthopanax senticosus polysaccharides(ASPS) on intestinal tight junction(TJ) disruption and nuclear factor-kappa B(NF-κB)/myosin light chain kinase(MLCK) activation in endotoxemia.METHODS BALB/C mice(6-8-weeks-old) received continuous intragastric gavage of ASPS for 7 d before injection of lipopolysaccharide(LPS), or received ASPS once after LPS injection. Blood and intestinal mucosal samples were collected 6 h after LPS challenge. Clinical symptoms, histological injury, intestinal permeability,TJ ultrastructure, and TJ protein expression were determined.RESULTS Compared with mice in the LPS group, pretreatment with ASPS improved clinical and histological scores by 390.9%(P < 0.05) and 57.89%(P < 0.05), respectively, and gut permeability change in endotoxemic mice was shown by a 61.93% reduction in reduced leakage of fluorescein isothiocyanate-dextran 6 h after LPS injection(P < 0.05). ASPS pretreatment also prevented LPS-induced TJ ultrastructure breakdown supported by increased electron dense materials between adjoining cells, sustained redistribution and expression of occludin(0.597 ± 0.027 vs 0.103 ± 0.009, P < 0.05) and zonula occludens-1(0.507 ± 0.032 vs 0.125 ± 0.019, P < 0.05), and suppressed activation of the NF-κB/MLCK pathway indicated by reduced expression of NF-κB, phospho-inhibitor kappa B-alpha, MLCK and phospho-myosin light-chain-2 by 16.06%(P < 0.05), 54.31%(P < 0.05), 66.10%(P < 0.05) and 64.82%(P < 0.05), respectively. CONCLUSION ASPS pretreatment may be associated with inhibition of the NF-κB/MLCK pathway and concomitant amelioration of LPS-induced TJ dysfunction of intestinal epithelium in endotoxemia.