ABSTRACT
Objective:
To explore the effect of herb-partitioned
moxibustion (HPM) on
tight junctions (TJs) of intestinal
epithelial cells in
Crohn disease (CD) mediated by
tumor necrosis factor-α (TNF-α)-
nuclear factor kappa B (NF-κB)-
myosin-
light- chain
kinase (MLCK) pathway.
Methods:
Forty-eight
male Sprague-Dawley rats were randomly divided into a normal control (NC) group, a model control (MC) group, an HPM group and a
mesalazine (MESA) group, with 12
rats in each group. Trinitrobenzene
sulfonic acid (TNBS) was administered to establish CD models. When the model was confirmed a success, the HPM group
rats were treated with HPM at Tianshu (ST 25) and Qihai (CV 6), while the MESA group
rats were given MESA
solution by
lavage. When the intervention finished, the colonic
epithelial tissues were
separated, purified and cultured in each group to establish the intestinal epithelial
barrier model
in vitro, and TNF-α was added (100 ng/mL) in the
culture medium and maintained for 24 h to establish an increased epithelial
permeability model. Transepithelial
electrical resistance (TEER) was used to examine the
permeability of the
barrier;
Western blot was used to observe the expressions of the
proteins related to TJs of intestinal
epithelial cells mediated by TNF-α-NF-κB-MLCK pathway;
immunofluorescence staining was used to observe the expressions and distributions of
tight junction proteins in the
intestinal epithelium.
Results:
After TNF-α induction, compared with the MC+TNF-α group, the TEER value increased significantly in the HPM+TNF-α and MESA+TNF-α groups (both P<0.001); the expressions of
nuclear factor kappa B (NF-κB) p65, MLCK,
myosin light chain (MLC),
tumor necrosis factor receptor-associated factor 6 (
TRAF6) and receptor interaction
protein-1 (RIP1) decreased significantly (P<0.01 or P<0.05), and the expression of
zinc finger protein A20 (A20) increased significantly (P<0.01); the expressions of
occludin,
claudin-1,
zonula occludens protein 1 (ZO-1) and
F-actin also increased significantly (all P<0.01). Compared with the MESA+TNF-α group, the expressions of MLC,
occludin,
claudin-1, ZO-1 and
F-actin increased significantly in the HPM+TNF-α group (P<0.01 or P<0.05).
Conclusion:
HPM can protect or repair the damage of intestinal epithelial
barrier in CD
rats, which may be achieved through modulating the abnormal TJs in
intestinal epithelium mediated by TNF-α-NF-κB-MLCK pathway.