Effects of Vitamin A and Montelukast on Airway Inflammatory Cells and Th1/Th2 Balance in Mouse Model of Asthma
|School||Anhui Medical University,|
|Keywords||Vitamin A Montelukast asthma inflammatory Cells TNF-a IFN-γ|
Objectives Through the establishment of the rat persistent asthma model, we took Vitamin A and Montelukast as the interventions, so as to compared the number of total and different cells in BALF as well as the level of TNF-a、IFN-γand IL-4 in serum and lung tissues in different weeks. At the same time, we try to investigate the pathogenesis of asthma and provide the theory basis for vitamin A in the prevention and treatment of bronchial asthma.Methods 40 rats were divided into A, B, C ,D four groups randomizedly, Group A for the Control group, Group B for Asthma group, Group C for the Oral Montelukast group, Group D for the Oral Vitamin A group. There were 10 rats in each group. On the 1st and 8th day of experiments, B, C, D groups were injected into abdominal cavity with sensitization fluid of 1.0 ml/only/times. On the 15th day of the experiments, the rats had been inhaled 1% OVA solution for 14 days in order to establish asthma models, daily one time, 30 minutes each time. The intervention of these three groups were as follows, each group was given the 1%OVA inhalation to carry on the stimulation as usual every morning, Group C was oral intragastric administration of Montelukast and vitamin A 10U a rat for Group D every afternoon, a total of a week. the rats were killed in two batches, each group of 7 / batch / times, first executed the rats by the way of Cervical dislocation, then takes cardiac blood 2.5ml ~ 5ml from each rat to determinate IL-4, IL-10 and IFN-γby the ELISA law. After tracheal intubation, lavage 3 times with 1ml PBS, then we obtain BALF 0.1ml to add 0.9 ml fluid white blood cell count, and count the number of white blood cell down the microscope. Made three pictures with the BALF centrifugated , then smear three pictures by Giemsa staining Results (1) The 36th day of the experiment,the number of total and different cells in BALF and the contents of TNF-a and IL-4 in serum and lung tissues of Asthma group were higher but the content of IFN-γlower than Control group and Montelukast group. All the differences were significant. Compared with Control group, all contents of Vitamin A group and Montelukast group were different significantly. At the same time, the differences between Vitamin A and Montelukast group were significant. (2) The 43th day of the experiment, the contents of TNF-a and IL-4 in serum and lung tissues of Asthma group were higher but the contents of IFN-γlower than the other three groups. All the differences were significantly. Compared with Control group, all contents of Vitamin A group and Montelukast group were different significantly. At the same time, the differences between Vitamin A and Montelukast group were significant except for the differences with IL-4 and IFN-γin serum .(3) The 43th day of the experiment: the number of total and different cells in BALF and the contents of TNF-a and IL-4 in serum and lung tissues of Vitamin A group were lower but the contents of IFN-γhigher than Vitamin A group of the 36th day of the experiments. All the differences were significantConclusions (1) The contents of TNF-a and IL-4 in serum and lung tissues of asthma rats increased significantly while the contents of IFN-γsignificantly decreased in the serum and lung. These may show that the Th1 / Th2 imbalance play an important role in the pathogenesis of asthma.(2) The 43th day of the experiment , Compared with Asthma group ,the levels of IFN-γof Vitamin A group and Montelukast group were higher while the levels of TNF-a and IL-4 were lower ,. These may suggest that both of Vitamin A and Montelukast have some effects of Regulating Th1 / Th2 imbalance. In the early stages of asthma,Vitamin A was ineffective and may even aggravate the local inflammatory (3) The oral intragastric administration of a low dose of vitamin A has some therapeutic effect on persistent asthma rats, but this therapeutic efficacy is weaker than that of Montelukast.