[Effects of fulvotomentoside on inflammatory factors and antiinflammatory factors in intestine of ovalbumin-sensitized BALB/c mice].

Objective: To investigate the effects of fulvotomentoside (Ful) on inflammatory factors and antiinflammatory factors in intestine of ovalbumin (OVA)-sensitized BALB/c mice, and to explore the mechanisms of its anti-food allergy effect.

Method: Twenty-four female BALB/c mice aged 6 weeks fed with ovalbumin-free feed were randomly divided into 3 groups, food allergy (FA) group, Ful group and normal saline (NS) group. Mice in FA and Ful groups were sensitized intraperitoneally two times with OVA and challenged intragastrically with OVA. Mice in Ful group were treated with 200 mg/kg of Ful by subcutaneous injection once daily for 22 days. The mice in FA and NS groups were used as positive control and negative control, respectively, and were treated with normal saline solution by subcutaneous injection for 22 days. Just 48 hours after the last challenge, the mice in each group were sacrificed and specimens of jejunum were taken. The mRNA expressions of transforming growth factor β1 (TGF-β1), interleukin-6 (IL-6), interleukin-17A (IL-17A) and forkhead box P3 (Foxp3) in jejunum were detected by reverse transcription-PCR (RT-PCR). The protein expressions of TGF-β1, IL-6, and IL-17A in jejunum were detected by immunohistochemical method. The activation of neutrophils in jejunum was assayed by the levels of MPO.

Result: The expressions of TGF-β1, IL-6, IL-17A mRNA [(0.370 ± 0.013), (0.475 ± 0.015), (0.541 ± 0.013)] and related protein [(53,075.70 ± 20,727.06), (256,881.66 ± 36,561.79), (435,064.25 ± 69,911.48)] in jejunum were increased and the Foxp3 mRNA [(0.231 ± 0.014) vs. (0.365 ± 0.015)] expression was decreased in group FA. After the treatment with Ful, IL-6 and IL-17A mRNA [(0.196 ± 0.005), (0.204 ± 0.008)] and protein [(114,040.30 ± 20,295.25), (218,200.74 ± 30,077.69)] expressions were decreased and Foxp3 mRNA (0.578 ± 0.021) expression was increased, and no change of TGF-β1 expression was unchanged. There were no significant differences of the levels of MPO among the three groups.

Conclusion: Inflammatory reaction which was characterized by the increase of IL-6 and IL-17A expressions was found in intestine of ovalbumin-sensitized BALB/c mice. Ful could decrease overexpression of IL-6 and IL-17A, and increase the expression of specific transcription factor Foxp3 of regulatory T cells significantly in intestine. It may be one of the mechanisms that Ful improved intestinal inflammation.