Mechanism Of Oxidative Stress In Asthma

Objective: Bronchial asthma,(named asthma), mainly festures isnon-specific airway inflammation, airway hyperresponsiveness and airwayremodeling.. Recent studies suggest that oxidative stress involved in thedevelopment of asthma. But the exact mechanism of oxidative stress inasthma, needs further study. This paper study for the oxidative stress inperipheral blood mononuclear cells of asthma patients and expression oftranscription protein of the nuclear factor kappa B (NF-κB) and8-oxoguanine DNA glycosylase (OGG1),explore proliferation of Hmy2.circell. Reasearch the possible mechanism of oxidative stress play inasthma.Content and methods: Part I:16cases collected in Luzhou MedicalCollege Affiliated Hospital of respiratory medicine from2011.2to2011.12.According to the criteria of GINA (Global Initiative for AsthmaGINA), we group into mild to moderate asthma group, severe asthma group(all patients in the acute stage)with their severity.normal healthy individualsserved as controls. Lymphocyte separation medium peripheral bloodmononuclear cells (PBMC) of standby. Intracellular reactive oxygen species(ROS) generated situation detected by2’,7’-dichlorofluorescein diacetate (2’,7’-dichlorofluorescin-diacetate, DCFH-DA), and dihydro-ethidium (DHE)way.; Explore SOD in serum by WST assay. Single cell gel electrophoresisassay to detected intracellular DNA damage. Intracellular OGG1protein andnuclear factor kappa B (NF-κB) in the expression detected by indirectfluorescence immunoassay determination. Enzyme-linked immunosorbentassay (ELISA) to measure serum tumor necrosis factor a (TNF-a) content. Part II: human B lymphoblastoid cells were stimulated with LPS and vitaminC to establish the oxidation and antioxidant cell model,2’,7’-dichloro-fluorescein diacetate (2’,7’-dichlorofluorescin-diacetate, DCFH-DA) way to probe ROS production situation; single-cell gel electrophoresisassay to detect DNA damage; tumor necrosis factor a (TNF-a) changesmeasured by enzyme-linked immunosorbent assay (ELISA). Using theCFDA SE (cell proliferation tracer fluorescent probes) an indirect method todetect cell proliferation. Results: The clinical trials:1. By the fluorescentprobe of DCFH-DA and DHE probes,the average fluorescence intensity inthe peripheral blood mononuclear cells of patients with asthma wassignificantly higher than the normal control group, in severe asthma is themost obvious. WST method microplate reader patients of SOD expressionwas significantly decreased. SOD express lowest in the severe group; underconfocal laser of single-cell gel electrophoresis of DNA damage: patientswith asthma exist deoxyribonucleic acid (DNA) damage, in severe asthmagroup DNA damage is the most obvious; OGG1positive expression byindirect fluorescence immunoassay shows the severe asthma group and mildto moderate asthma group was significantly higher than the control group,the severe asthma group is the highest; The same method for thedetermination of NF-κB in peripheral blood mononuclear cells, the asthmagroup than in the control group was significantly higher;2cells (human Blymphoblastoid cells) test: measured ROS by the fluorescent probeDCFH-DA method, ROS production was reduced in LPS+vitamin Cstimulation group than in LPS-stimulated group,and there’s no significantdifference with the normal control group; single cell gel electrophoresisresults showed that LPS stimulation of cell DNA damage is the mostobvious, and LPS+vitamin C to stimulate the degree of DNA damage mitigation, but compared with control group there is still a certain degree ofdamage. TNF-a expression of supernatant levels LPS group is the mostobvious;detect cell proliferation by CFDA SA method view, cellproliferation by LPS in a dose-related, and LPS+vitamin C can inhibit cellproliferation.Conclusion:1. Oxidative stress involved in the development ofasthma,and plays an important role in the pathogenesis,there’a a closerelationship between oxidative stress and asthma severity of illness;oxidative stress involved in DNA damage, mediated OGG1and NF-κBexpression in peripheral mononuclear cells.2. LPS can successfullyestablish the cellular oxidative stress model, causing DNA damage,antioxidant can reduce oxidative DNA damage. Oxidative stress promotecell proliferation, and participate to increase the expression of cytokinesTNF-a.