Effect Of Tumor Necrosis Factor Alpha On The Levels Of Leukotriene D4、leukotriene E4in Balf And Expression Of CysLTR1in Lung Tissue In Asthma Mice Model

Objective: To explore whether TNF-α involving the modulation of levelsof leukotriene D4、 leukotriene E4in the in broncho alveolar lavage fluid（BALF） and expression of Cysteinyl leukotriene receptor1(CysLTR1) inlungs tissue in asthma mice model.Methods: Forty-eight BALB/c mice wererandomly assigned into normal control(A group),asthma group(B group),inhaled low dose TNF-α group（C1group）、inhaled high dose TNF-αgroup（C2group）、injected low dose TNF-α group（D1group）and injected high doseTNF-α groups（D2group）(n=8each). The mice were sensitized with ovalbuminto establish the asthmatic model. The histological changes were evaluated byhematoxylin and eosin staining, BALF were collected, the total cell and the celldifferentials were counted, the levels of leukotriene D4and leukotriene E4were measured by enzyme-linked immunosorbent assay(ELISA), andImmunohistochemistry(IHC)、 Real-time quantitative Polymerase ChainReaction（Q-PCR）and western blotting（WB）were performed to detect theexpression of CysLTR1in all groups. SPSS17.0software was used to analyzethe data. Results:1. Compared with the control group, the asthma group andTNF-α intervention group revealed significantly airway inflammatory changesin lung tissue biopsy which were higher in the intervention group airwayinflammation than asthma group2. Group LTD4content in BALF were (19.28±2.34) μg/L,(24.45±3.17) μg/L,(25.93±6.63) μg/L,(31.63±4.18) μg/L, (26.04±5.98) μg/L,(31.06±5.77) μg/L; groups LTE4content (40.00±2.71)ng/L,(46.90±3.91) ng/L,(52.16±2.73) ng/L,(53.41±5.01)ng/L,(50.41±4.70) ng/L,(52.26±4.70) ng/L. Between group C1and D1group, thedifference between the C2group and the D2group without statistical, the rest ofany difference between the two groups were statistically significant (P <0.05)3.BALF EOS count case (0.01±0.00)×106/L,(1.76±0.80)×106/L,(2.80±0.27)×106/L,(3.47±0.60)×106/L,(2.68±0.47)×106/L,(3.58±0.54)×106/L. Between group C1and D1group, the difference between the C2groupand the D2group without statistical, the rest of any difference between the twogroups were statistically significant (P <0.05)4. IHC CysLTR1positive cellscount in different groups as follows:22.899±1.236、26.333±3.240、33.222±4.585、51.888±6.988、39.010±5.232、52.222±6.593. Between b and C1, C2,and D2no statistical differences between groups, any remaining differencesbetween the two groups were statistically significant (P<0.05)(5) Real-timefluorescence quantitative polymerase chain reaction method for detectingCysLTR1gene expression for each group relative density of0.218±0.050respectively,0.418±0.050、0.923±0.084、1.258±0.083、1.853±0.089、1.337±0.085、1.670±0.138, which C1group and D1group Zhijian, and C2groupand D2group Zhijian differences no statistics sexual, remaining any two groupbetween differences are has statistics significance (P<0.05)(6) WB detection theGroup of CysLTR1protein relative density respectively for0.797±0.081, and1.422±0.97, and1.784±0.210, and2.448±0.096, and2.023±0.058, and2.933±0.034which b group and C1group, and C2and D2no statisticaldifferences between groups, and any remaining differences between the twogroups were statistically significant (P<0.05).Conclusions:(1) TNF-α inducethe production of inflammatory mediators LTD4and LTE4, and the transmigration、 exudation of EOS and other inflammatory cells intoairway,which could all cause keep current or even aggrevate the pathologicalchanges. This may be one of the mechamisms about the annapphylacticinflammation in asthma.(2) TNF-α induce upregulation of CysLTR1expressionin lung tissue, when respiratory tract infected by virus, it produce abundantTNF-α, which enhanced inflammational reaction in respiratory tract. It mayexplain the mechanism partially that virus respiratory tract infection inducedexacerbation of asthma.