Relationship of HMGB1 and TLR4 with airway inflammation in asthma and the role of vitamin D / 西安交通大学学报(医学版)

ABSTRACT

Objective To evaluate the relationship of high mobility group box 1 (HMGB1) and TLR4 with airway inflammation and the role of vitamin D.Methods Totally 24 BALB/c mice were randomly divided into control group,asthma group,and 1,25-(OH)2D3 group,each having 8 mice.The pathological changes in lung tissue of the mice were observed by hematoxylin-eosin (HE) staining,bronchial wall thickness was measured with computer pathological image analysis system software.The expressions of HMGB1 and TLR4 in lung tissue were detected by immunohistochemical method.Bronchoalveolar lavage fluid (BALF) was collected for cytological examination;the contents of HMGB1,TLR4,IL-4 and IFN-γ in BALF and the peripheral blood were detected by enzyme-linked immunosorbent assay (ELISA).Results The expressions of HMGB1 and TLR4 in lung tissue were stronger in asthma group,but weaker in intervention group.The total number of leukocytes as well as the percentages of eosinophils,neutrophils and lymphocytes increased significantly in BALF in asthma group,but significantly decreased in intervention group (all P ＜ 0.05).The ratio of monocyte/macrophage significantly decreased in asthma group,but increased significantly in intervention group (P＜0.05).The contents of HMGB1,TLR4 and IL-4 in BALF and the peripheral blood were significantly higher in asthma group than in control and intervention groups,whereas IFN-γ level was significantly lower than that in control and intervention groups (all P＜0.05).HMGB1 and TLR4 contents had a positive correlation with the total number of cells and IL-4 concentration in BALF,respectively (r1=0.796,0.730;r2=0.695,0.648;all P＜0.05).Conclusion HMGB1 and TLR4 were associated with airway inflammation and immune disorders.An appropriate amount of 1,25-(OH)2D3 can relieve airway inflammation,which may be associated with regulating Th1/Th2 cells balance.