Study On The Mechanism Of Treating Neutrophil Elastic Protease In Chronic Obstructive Pulmonary Disease

Background Chronic Obstructive Pulmonary Disease (COPD), a common preventable and treatable disease, is characterized by persistent airflow limitation that is usually progressive and associated with an enhanced chronic inflammatory response in the airways and the lung to noxious particles or gases. Exacerbations and comorbidities contribute to the overall severity in individual patients. At present the pathogenesis of COPD has not yet fully understood, but oxidative stress, inflammatory reaction, protease-antiprotease imbalance, dysfunction of autonomic nerve play important roles according to document research. Further study should be down to reveal the main pathogenesis of COPD. Lifei decoction is an effective decoction of my tutor which has gained an invention patent. According to former experimental and clinical research of our research team, we found that Lifei decoction can treat the airway inflammatory diseases such as asthma and COPD and have good clinical effect for patients with deficiency of the lung spleen and kidney under TCM syndrome differentiation. Previous clinical and experimental research has also confirmed its oxidative stress resistance, inflammation control and immune regulation effect. But whether Lifei decoction influences the protease-antiprotease imbalance? What is the relationship between protease-antiprotease imbalance and inflammatory factors? In order to know the underlying mechanism, we carried out the study using Lifei decoction to intervene the oxidative stress COPD rat on the basis of traditional narrative review and systematic review for protease-antiprotease imbalance and inflammatory reaction of stable COPD patients.Objectives To understand the effects of traditional Chinese medicine on inflammatory factors and protease system in patients with stable COPD objectively, to evaluate the influence of Lifei decoction towards protease-antiprotease imbalance and inflammatory factors in oxidative stress COPD rats objectively and to explore the mechanism of Lifei decoction in regulate and control protease-antiprotease imbalance and inflammatory factors in oxidative stress COPD rats.Methods1. To establish oxidative stress COPD animal model by Cigarette smoking exposure, intratracheal instillation of lipopolysaccharide and ozone exposure, experimental rats were randomly divide into 7groups(normal group, model group, DMP777 group, dexamethasone group, low dose group of Lifei decoction, middle dose group of Lifei decoction, high dose group of Lifei decoction),each group of 10. In the study, modelling time was 120 days and administration time was 4weeks.2. Observation indexes including the general situation in rats, lung function by anires2005 small animal lung function instrument, characteristics of pathological sections of the lungs by optical microscope, the level of GM-CSF、IL-6、IL-8、PAF、 TGF-β1、ET、NE、α1-AT in lung homogenates and serum by ELISA, the level of Elastin in pathological sections of the lungs by immunohistochemistry and IPP6 software3. Using the method of multivariate logistic analysis to explore the relationship between GM-CSF、IL-6、IL-8、PAF、TGF-β1、ET and NE、α1-AT、NE/α1-AT in lung homogenates and serum of COPD rats.Results1. In this study, cigarette smoking exposure, intratracheal instillation of lipopolysaccharide and ozone exposure can lead to COPD inflammation reaction of rats. Oxidative stress COPD rats had a weight loss, reduced pulmonary function, inflammatory cells infiltration of lung tissue, emphysema and a risen lever of IL-6, IL-8, ET, PAF, GM-CSF, TGF-β1 and NE level in lung homogenates and serum of rats.2. Lung tissue HE staining results showed that different dose of Lifei decoction can improve the inflammatory cell infiltration of lung tissue, emphysema, and pathological phenomena such as mucus secretion. The high and middle dose of Lifei decoction can better improve lung tissue inflammation, luminal stenosis, bronchial and vascular smooth muscle hyperplasia, epithelial cell detachment, goblet cell and gland hyperplasia and alveolar enlargement than the low dose of Lifei decoction. Immunohistochemical and image analysis showed that protease-antiprotease imbalance, alveolar wall destruction, alveolar fusion and emphysema exist in COPD rats reflected by Elastin measurement which meet the result of HE staining. Dexamethasone group and high dose group of Lifei decoction have a higher expression of lung Elastin.3. Lifei decoction can improve lung function indexes (FVC、FEF25%、MMF、PEF, FMFT) of COPD rats and improve ventilation function in rats. Middle dose of Lifei Decoction group improves above indexes better than other groups.4. Lifei decoction can improve systemic inflammatory response of oxidative stress COPD rats by influence the level of IL-6, IL-8, ET, PAF GM-CSF and TGF-β1 in lung homogenates and serum. The high dose of Lifei decoction better improve IL-6、 IL-8、TGF-β1、GM-CSF level than other groups, The low dose of Lifei decoction better improve ET、GM-CSF level than other groups.5. Lifei decoction can improve protease-antiprotease imbalance of oxidative stress COPD rats by reduce the Level of NE, NE/al-AT, and increase the Level of al-AT in lung homogenates and serum. The high dose of Lifei decoction can better reduce the level of NE in lung homogenates than dexamethasone group and DMP777 group. The effects of high dose of Lifei decoction and dexamethasone in increasing the Level of al-AT in lung homogenates are similar. The middle dose of Lifei decoction can better reduce the level of NE/al-AT than dexamethasone group and DMP777 group in lung homogenates and serum.6. NE level of Oxidative stress COPD Rats in serum was positively correlated with IL-8 and TGF-β1、NE level of Oxidative stress COPD Rats in lung homogenates was positively correlated with ET、GM-CSF and TGF-β1.α1-AT level of Oxidative stress COPD Rats in serum was positively correlated with ET,GM-CSF,IL-6 and PAF, al-AT level of Oxidative stress COPD Rats in lung homogenates was positively correlated with ET,GM-CSF,IL-8 and TGF-β1. The value of NE/α1-AT in serum was positively correlated with ET and TGF-β1, The value of NE/al-AT in lung homogenates was positively correlated with ET、GM-CSF,IL-8,PAF and TGF-β1Conclusions1. Through model evaluation, the COPD model was successfully established in SD rats by using the method of cigarette smoke exposure combined with LPS instillation and ozone exposure. Inflammatory response and protease-antiprotease imbalance is the focus of this study.2. Lifei decoction can improve lung function indexes (FVC、FEF25%、MMF、PEF, FMFT) of oxidative stress COPD rats and improve ventilation function in rats.3. Different dose of Lifei decoction can improve the inflammatory cell infiltration of lung tissue, emphysema, and pathological phenomena such as mucus secretion. The high and middle dose of Lifei decoction can better improve lung tissue inflammation, luminal stenosis, bronchial and vascular smooth muscle hyperplasia, epithelial cell detachment, goblet cell and gland hyperplasia and alveolar enlargement than the low dose of Lifei decoction. Dexamethasone group and high dose group of Lifei decoction have a higher expression of lung Elastin. Thus, Lifei decoction can improve the protease-antiprotease imbalance and prevent lung tissue structural protein dissolved, and inhibit lung damage.4. Lifei decoction can improve lung inflammation and systemic inflammatory of oxidative stress COPD Rats by influence the level of IL-6, IL-8, ET, PAF GM-CSF and TGF-β1 in lung homogenates and serum. The high dose of Lifei decoction better improves IL-6、IL-8、TGF-β1、GM-CSF level than other groups, The low dose of Lifei decoction better improves ET、GM-CSF level than other groups.5. Lifei decoction can improve the Level of NE, al-AT and NE/al-AT of oxidative stress COPD rats, the high dose of Lifei decoction can better reduce the level of NE in lung homogenates than dexamethasone group and DMP777 group. The effect of high dose of Lifei decoction and dexamethasone in increasing the Level of al-AT in lung homogenates are similar. The middle dose of Lifei decoction can better reduce the level of NE/al-AT than dexamethasone group and DMP777 group in lung homogenates and serum.6. The level of NE、α1-AT in lung homogenates and serum of oxidative stress COPD rats was positively correlated with the level of IL-8, TGF-1, ET, GM-CSF, IL-6 and PAF.There were close relationship between the inflammatory response and protease-antiprotease imbalance. Meanwhile, inflammatory factors can cause protease-antiprotease imbalance7. Lifei decoction can direct or indirect regulate NE, al-AT and NE/al-AT levels in lung homogenates and serum, to reduce COPD rats lung tissue elastin degradation and to delay the lung tissue injury.