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

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.