Exploration Of The Therapeutic Effect And Preliminary Mechanism Of Spleen Aminopeptide Oral Solution On Experimental Allergic Rhinitis

BACKGROUND: Immunomodulators are an option for the treatment of allergic rhinitis(AR)and can reduce the level of AR inflammation by modulating the immunity of AR patients.In this study,we investigated the therapeutic effects and preliminary mechanism of the immunomodulator spleen aminopeptide oral solution(SAOS)on experimental AR by establishing an OVA-sensitized AR mouse model.METHODS: Fifty healthy female BALB/c mice were randomly divided into five groups: blank control group,AR model control group,SAOS high-dose group,SAOS medium-dose group and SAOS low-dose group.The AR mouse model was established by using ovalbumin(OVA)to sensitize BALB/c mice.A mixture of OVA and aluminium hydroxide was injected intraperitoneally every other day for 2 weeks as basic sensitization,followed by daily nasal drops of OVA solution for 2 weeks as intensive sensitization and daily gavage of SAOS.Behavioural scoring,serum IL-4,IL-5 and IL-17 A levels and nasal mucosal pathology were performed after the last intensive sensitization.RESULTS: Behavioural scores were obtained for each group of mice at the end of intensive sensitization,i.e.2 weeks after dosing.The behavioural scores showed that both the AR model control group and the dosing groups were successfully modelled(behavioural score >5).The behavioral scores of the AR modeling group and the middle and low dose groups were significantly higher than those of the blank control group(P<0.05),while the difference between the behavioral scores of the high dose group and the blank control group was not statistically significant(P>0.05);the difference between the behavioral scores of the AR modeling control group and each dosing group was not statistically significant(P>0.05),but the scores tended to decrease with increasing dose.Serum IL-4 and IL-5 levels decreased significantly in each dosing group compared to the AR model control group(P<0.05),but the difference in IL-17 A levels compared to the AR model control group was not statistically significant(P>0.05).Pathological results showed that both the AR model control group and the dosing group had different degrees of nasal mucosal epithelial thickening,destruction of epithelial structures,loss of cilia,cupped cell hyperplasia and inflammatory cell infiltration.However,the inflammatory condition of the nasal mucosa improved with increasing dose of the drug.The thickness of the nasal mucosa in the high and medium dose groups was significantly less than that in the AR model control group(P<0.05).CONCLUSION: SAOS can reduce the levels of IL-4 and IL-5 in peripheral blood of AR mice,decrease the Th2 response and promote the restoration of Th1/Th2 balance,but has no significant effect on the Th17 response;it can also reduce the inflammation in the nasal cavity to a certain extent,reduce the inflammatory cell infiltration in the nasal mucosa and protect the integrity of cilia and epithelium.