Diosmetin alleviates intestinal epithelial barrier damage in
vitro and in vivo
As shown in Fig. 2A, B compared to the control group, the expression
levels of tight junction proteins
(Occludin and Claudin) in the mice
of DSS only group were observably decreased, however, diosmetin and SASP
were able to markedly increase the expression of Occludin and Claudin
compared to the model group. In addition, the results of
immunofluorescence analysis of ZO-1 as shown in Fig. 2C, D, the
expression levels of ZO-1 in colon sections were markedly decreased
after DSS treatment in vivo compared to the control groups. These levels
were significantly up-regulated when the cells were pre-treated with
diosmetin and SASP. Next, we analyzed
the expression of tight junction
proteins, Occludin and Claudin, by
Western blot after 24 h exposure to different concentrations
(0.1–30μg/ml) of LPS in caco2 and IEC-6 cells. As shown in Fig. 3A, the
levels of expression of Occludin and Claudin were obviously decreased in
a dose-dependent way for the caco2 and IEC-6 cells in LPS-treated group.
Furthermore, the expression level
of Occludin and Claudin
administrated with LPS (30 μg) was significantly decreased.After
pretreatment with diosmetin (25-100 ng/mL) for 24 h, the levels of
expression of Occludin and Claudin were obviously
increased in caco2 and IEC-6 cells
(Fig. 3B). As shown in Fig. 3C, D, the immunofluorescence analysis of
ZO-1 exhibited similar results.
Diosmetin
reduced pro-inflammatory cytokines in vivo
The effects of diosmetin on the expression of inflammation related genes
were studied at mRNA level shown in Fig. 4. diosmetin (50 mg/kg)
significantly inhibited the expression of IL-1β, IL-6, cyclooxygenase-2
(COX-2) and IFN-γ (p<0.05) Compared to 3% DSS only group (Fig4 A-D).
Compared to 5% DSS only group, diosmetin (50 mg/kg) significantly
inhibited the expression of IL-1β, IL-6, cyclooxygenase-2 (COX-2) and
IFN-γ (p<0.05) (Fig. 4E- H).