Dynamic Characteristics of Sequential Acute Exacerbations and Risk Windows in AECOPD Rats Induced by Cigarette-Smoke and Exposure to Klebsiella pneumoniae.

The risk-window (RW) of chronic obstructive pulmonary disease (COPD) is a period after an acute exacerbation (AE) but before the following stable phase, in which exacerbations are easy to relapse. We established a sequential COPD-AE-RW rat model by cigarette-smoke and bacterial exposures in the first 8 weeks, and was challenged with Klebsiella pneumonia to mimic an AE on Day 1 of week 9, and found that body temperature, white blood cell, neutrophils, serum amyloid A (SAA) and C-reactive protein (CRP) increased in AECOPD rats 24 h after challenge, and declined in 3-6 d, while lung function declined in 48 h, and recovered in 7-16 d. When sacrificed, pulmonary forced expiratory volume (FEV)100 and FEV300 decreased, while elevated bronchoalveolar lavage fluid (BALF) neutrophils and marked airway inflammation, remodeling and emphysema were observed. Sequential COPD-AE-RW rat model was established successfully and AE phase lasts for approximately 5-7 d, followed by a 10-d around risk-window.

Sequential Treatments with Tongsai and Bufei Yishen Granules Reduce Inflammation and Improve Pulmonary Function in Acute Exacerbation-Risk Window of Chronic Obstructive Pulmonary Disease in Rats.

Background. Sequential treatments of Chinese medicines for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) risk window (RW) have benefits for preventing reoccurrences of AEs; however, the effects on pulmonary function, pulmonary, and systemic inflammatory biomarkers remain unclear. Methods. Cigarette-smoke/bacterial infections induced rats were randomized into Control, COPD, AECOPD, Tongsai Granule/normal saline (TSG/NS), moxifloxacin + salbutamol/NS (MXF+STL/NS), TSG/Bufei Yishen Granule (BYG), MXF+STL/STL, and TSG+MXF+STL/BYG+STL groups and given corresponding medicine(s) in AE- and/or RW phase. Body temperature, pulmonary function, blood cytology, serum amyloid A (SAA) and C-reactive protein (CRP), pulmonary histomorphology and myeloperoxidase (MPO), polymorphonuclear (PMN) elastase, interleukins IL-1ß, IL-6, and IL-10, and tumor necrosis factor- (TNF-) α expressions were determined. Results. Body temperature, inflammatory cells and cytokines, SAA, CRP, and pulmonary impairment were higher in AECOPD rats than stable COPD, while pulmonary function declined and recovered to COPD level in 14-18 days. All biomarkers were improved in treated groups with shorter recovery times of 4-10 days, especially in TSG+MXF+STL/BYG+STL group. Conclusion. Sequential treatments with Tongsai and Bufei Yishen Granules, during AECOPD-RW periods, can reduce inflammatory response and improve pulmonary function and shorten the recovery courses of AEs, especially the integrated Chinese and Western medicines.