PHI reduced the infiltration of inflammatory cells
Neutrophils and macrophages infiltrations are recognized as evaluative
parameters for the severity degree of colitis, and flow cytometry was
used to assess changes in the immune cell populations in MLN and
peripheral blood. The population of monocytes
(CD11b+), macrophages
(CD11b+F4/80+), neutrophils
(CD11b+Ly6G+), and dendritic cells
(CD11b+CD11c+) were significantly
increased in both MLN and peripheral blood of DSS-induced UC mice.
However, both high and low doses of PHI were found to reduce the
population of macrophages in MLN and peripheral blood monocyte cells,
with high doses of PHI having an inhibitory effect on neutrophils of
PBMC (Fig. 4A-B). In TNBS-induced mice, the population of macrophages
decreased, and PHI reduced the level, which was consistent with the
findings in DSS-induced mice(Fig. 4C-D). Immunofluorescent staining with
F4/80 showed severe infiltrations of macrophages in DSS-induced mice
colon, which were reduced by PHI (Fig. 4E), suggesting that future
research may focus on macrophages’ role in the mechanism of action of
PHI.