Effect of dihydromyricetin on regulatory B cells in experimental colitis mice

Objective To explore effects of Dihydromyricetin (DHM) on experimental colitis and regulatory B cells(Breg) of mice. Methods The mice were randomly divided into control group, DSS group, DSS+DHM group and DSS+ mesalazine group (4% DSS for 7 days). After 7 days, the mice were respectively gavaged with water (0.2 mL/d),DHM (40 mg/kg·d) and mesalazine (520 mg/kg·d) for 7 consecutive days and the disease activity index (DAI) was continuously recorded. The animals were sacrificed on the 14th day and the colon length was measured. The colon tissue sections were microscopied with HE staining. CD19+B lymphocytes and Breg(CD19+CD5+CD1d+) were determined by flow cytometry in splenic single cell suspension; real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the relative mRNA level of IL-10,TGF-β,IL-6 and IFN-γin spleen cells. The effect of DHM on the proliferation of spleen cells was measured by CCK8. DHM (40 μmol/L) was selected to act on the spleen cell suspension for 24 h. flow cytometry was used to