Effect of different 1, 25-(OH)2D3 doses on high mobility group box1 and toll-like receptors 4 expression in lung tissue of asthmatic mice.

We established a mouse model of asthmatic airway remodeling. To investigate the effects of different doses of 1,2 5-(OH)2D3 on airway remodeling, expression of high mobility group box 1 (HMGB1) and Toll-like receptors 4 (TLR4) in asthmatic mice. The female mice (BALB/c) groups consisted of a control group, asthma group and 1,2 5-(OH)2D3 low, middle, high dose group. Each group contained 10 mice. An asthmatic mice model was induced by ovalbumin. The control group and asthma group used physiological saline instead. 1,2 5-(OH)2D3 low, middle and high dose group was given different doses of 1,2 5-(OH)2D3 respectively. Changes in mice airway structure were observed by hematoxylin-eosin (H&E). The expression of HMGB1 and TLR4 in molecular lever were monitored by RT-PCR. We used immunohistochemistry to test HMGB1 and TLR4 protein levels. Obvious changes were noted in the airway of OVA-induced asthma mice compared with the control group by HE. These changes were less pronounced in mice receiving the low and middle doses of 1,2 5-(OH)2D3, but were more pronounced in mice receiving the highest dose of 1,2 5-(OH)2D3. Immunohistochemistry showed that expression of HMGB1 and TLR4 in the asthma group was higher than the control group. And low and middle dose group was decreased compared with asthma group, while higher than the control group; high dose group had an increased expression compared with the asthma group. From RT-PCR we got the same results as immunohistochemistry. In the asthmatic airway remodeling animal model, the appropriate amount of 1,2 5-(OH)2D3 reduced airway remodeling in asthmatic mice, and decreased the expression of HMGB1 and TLR4 in the asthmatic mice. However, over dose might play detrimental effect.