PHI ameliorated DSS-induced murine acute ulcerative colitis
We first investigated the therapeutic effects of PHI in DSS-induced colitis. 2% Dextran Sulfate Sodium (DSS) in drinking water ad libitum for 7 consecutive days, followed by treatment with different doses of PHI (60 mg/kg and 20 mg/kg) throughout the whole experiment (Fig. 2A)
Using disease activity index (DAI) as a measure of UC severity, the mice in both DSS- and 2,4,6-trinitro-Benzenesulfonic acid (TNBS)-induced colitis experienced significant weight loss, severe diarrhea, and bloody stool after chemical induction. Treatment with PHI resulted in a reversal of these symptoms, as well as a restoration of immune hyperfunction-induced splenomegaly and colon shortening (Fig. 2B and 2C). PHI also exerted positive effects on maintaining the intestinal mucosal barrier by reducing goblet cell loss, mucous thinning, and intestinal permeability (Fig. 2D, E).
In addition, the histologic analysis indicated that PHI treatment restored the colon structure, prevented crypt destruction, and inhibited inflammatory cell infiltration. The expression of tight junction proteins in the colon was also restored, further demonstrating PHI’s beneficial effect on intestinal barrier function (Fig. 2F).