Effects of Loquat Leaf Extract on Airway Inflammation and Airway Remodeling Induced by Ovalbumin in Asthmatic Mice

OBJECTIVE To explore the therapeutic effect of Loquat leaf extract on asthma mice model. METHODS Sixty BALB/c mice were randomly divided into 6 groups, blank group, model group, Loquat leaf extract low, medium and high dose groups(50, 100, 150 mg·kg^-1), dexamethasone group(0.5 mg·kg^-1, positive control). Ovalbumin(OVA) induced asthma mouse model, each group of mice were gavaged with corresponding drugs. The airway hyperresponsiveness of mice was detected 24 h after the last OVA modelling. The number of inflammatory cells in bronchoalveolar lavage fluid was counted by Wright-Giemsa staining classification. The levels of Eotaxin, IL-4, IL-5, IL-13 and OVA-specific IgE(OVA-sIgE) were detected by ELISA. HE and AB-PAS staining were used to observe the pathological changes of mice lung tissue. Western blotting was used to detect the expression of AKT, p-AKT, PI3K and Cyclin D1 in lung tissue. RESULTS Loquat leaf extract(100, 150 mg·kg^-1) could effectively reduce the number of inflammatory cells including eosinophils, macrophages, lymphocytes, and neutrophils; reduce the expression levels of Eotaxin, IL-4, IL-5, IL-13 and OVA-sIgE; inhibit the infiltration and mucus secretion of inflammatory cells in the lung tissue of asthmatic mice; inhibit the protein expression of AKT, p-AKT, PI3K and Cyclin D1 in asthma models. CONCLUSION Loquat leaf extract has a good inhibitory effect on OVA-induced airway inflammation in asthma, which can provide a reference for the study of Loquat leaf in the treatment of asthma.