Inhibitory effect of L-shikonin on allergic rhinitis in mice

CHEN Wubing; WANG Yilong; YING Yongjie

doi:10.13276/j.issn.2097-1656.2024.06.017

Abstract：Objective To investigate the therapeutic effect of L-shikonin on mice with allergic rhinitis(AR)and its related inhibitory mechanism.Methods Ovalbumin(OVA)-sensitized AR mouse model was established.According to random number table method,25 C57BL/6 mice were randomly divided into normal group,AR model group,low-dose and high-dose L-shikonin groups,and standard control group,with 5 mice in each group.In addition to the normal group,the other groups completed AR model construction:OVA+aluminum hydroxide gel mixed preparation was used for sensitization on the 1st,5th,9th and 12th day,and OVA was used for stimulation once a day for seven consecutive days starting from the 13th day.Starting from the 28th day of modeling,the mice in the L-shikonin group were administered with 2 and 8 mg/(kg·d)L-shikonin by gavage.The mice in the standard control group were given 2.5 mg/(kg·d)of dexamethasone by gavage,while the normal group and AR model group were given an equal dose of dimethyl sulfoxide by gavage for a total of 4 weeks.Within 30 min of the last gavage,nasal symptoms of each group of mice were observed and scored.Flow cytometry was used to detect the expression levels of T helper(Th)1 and Th2 cell subsets in peripheral blood of mice.ELISA was used to detect the levels of interleukin-4(IL-4),immunoglobulin E(IgE),and γ-interferon(IFN-γ)in the nasal lavage fluid of mice.HE staining was used to detect pathological changes in the nasal mucosa.qRT-PCR was used to detect the mRNA expression of T-box transcription factor(T-bet),GATA binding protein 3(GATA3),signal transducer and activator of transcription 1(STAT1),and STAT6 in nasal mucosal tissue.Results After 4 weeks of administration,compared with normal group,behavioral scores,Th1 cell proportion,IL-4 and IgE levels,and GATA3 and STAT6 mRNA expressions were significantly increased in AR model group(P＜0.05),while Th2 cell proportion,IFN-γ level,and T-bet and STAT1 mRNA expressions were significantly decreased in AR model group(P＜0.05).Compared with AR model group,behavioral scores,Th1 and Th2 cell proportions,IL-4,IgE and IFN-γ levels,and T-bet mRNA expression of animals in low-dose L-shikonin group had almost no changes(P＞0.05),while STAT1 mRNA expression was significantly increased(P＜0.05),and GATA3 and STAT6 mRNA expressions were significantly decreased(P＜0.05).Compared with AR model group,behavioral scores,Th1 cell proportion,IL-4 and IgE levels,and GATA3 and STAT6 mRNA expressions in high-dose L-shikonin group were significantly decreased(P＜0.05),and Th2 cell proportion,IFN-γ level,and T-bet and STAT1 mRNA expressions were significantly increased(P＜0.05).Compared with low-dose L-shikonin group,Th1 cell proportion,IL-4 and IgE levels,and GATA3 and STAT6 mRNA expressions in peripheral blood of high-dose L-shikonin group were significantly decreased(P＜0.05),and Th2 cell proportion,IFN-γ level,and T-bet and STAT1 mRNA expressions were significantly increased(P＜0.05).Conclusion High-dose L-shikonin has a certain improvement effect on AR in mice,and its main potential mechanism for reducing inflammation may be to regulate Th1/Th2 imbalance through JAK/T-bet/STAT1 and JAK/GATA3/STAT6 pathways.