In this study, the effect of prophylactic anti-inflammation on the development of smoke-induced emphysema was investigated. Young male guinea-pigs aged 1.5-2 months (weighing 198.3+/-26.9 g) were randomly divided into 4 groups: group A (cigarette smoke exposure only), group B (cigarette smoke exposure plus pentoxifylline-rich (PTX, 10 mg/d) forage feeding), group C (cigarette smoke exposure plus intermittent cortical steroid injection (Triamcinolone acetonide, 3 mg, i.m., every three weeks) and control group (group D: animals with sham smoke exposure, raised under the same conditions). Animals in group A, B and C were exposed to smoke of cigarettes for 1 to 1.5 h twice a day, 5 days a week. All animals were killed at the 16th week and followed by morphometrical analysis of the midsagittal sectioned lung slices. Smoke exposure of 16 weeks resulted in visible emphysematous development in Group A but not in Group B and C. It was evidenced by the indicator of air-space size, mean linear intercept (Lm): 120.6+/-16.0 microm in Group A; 89.8+/-9.2 microm in Group B and 102.4+/-17.7 microm in Group C. The average Lm in either group B or group C was shorter than that in Group A (ANOVA and Newman-Keuls test, F=8.80, P=0.0002) but comparable to that (94.8+/-13.2 microm) in group D (P>0.05). It is concluded that long-term prophylactic anti-inflammation inhibits pulmonary emphysema induced by cigarette smoking in the guinea pigs.
Anti-Inflammatory Agents/*pharmacology ; Pentoxifylline/pharmacology ; Pulmonary Emphysema/etiology ; Pulmonary Emphysema/pathology ; Pulmonary Emphysema/*prevention & control ; Random Allocation ; Smoking/*adverse effects ; Triamcinolone Acetonide/*pharmacology

In this study, the effect of prophylactic anti-inflammation on the development of smoke-induced emphysema was investigated. Young male guinea-pigs aged 1.5-2 months (weighing 198.3+/-26.9 g) were randomly divided into 4 groups: group A (cigarette smoke exposure only), group B (cigarette smoke exposure plus pentoxifylline-rich (PTX, 10 mg/d) forage feeding), group C (cigarette smoke exposure plus intermittent cortical steroid injection (Triamcinolone acetonide, 3 mg, i.m., every three weeks) and control group (group D: animals with sham smoke exposure, raised under the same conditions). Animals in group A, B and C were exposed to smoke of cigarettes for 1 to 1.5 h twice a day, 5 days a week. All animals were killed at the 16th week and followed by morphometrical analysis of the midsagittal sectioned lung slices. Smoke exposure of 16 weeks resulted in visible emphysematous development in Group A but not in Group B and C. It was evidenced by the indicator of air-space size, mean linear intercept (Lm): 120.6+/-16.0 microm in Group A; 89.8+/-9.2 microm in Group B and 102.4+/-17.7 microm in Group C. The average Lm in either group B or group C was shorter than that in Group A (ANOVA and Newman-Keuls test, F=8.80, P=0.0002) but comparable to that (94.8+/-13.2 microm) in group D (P>0.05). It is concluded that long-term prophylactic anti-inflammation inhibits pulmonary emphysema induced by cigarette smoking in the guinea pigs.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Guinea Pigs ; Male ; Pentoxifylline ; pharmacology ; Pulmonary Emphysema ; etiology ; pathology ; prevention & control ; Random Allocation ; Smoking ; adverse effects ; Triamcinolone Acetonide ; pharmacology

Recent clinical evidence indicates that the non-eosinophilic subtype of severe asthma is characterized by fixed airway obstruction, which may be related to emphysema. Transgenic studies have demonstrated that high levels of IFN-gamma in the airways induce emphysema. Fibroblast growth factor 2 (FGF2), which is the downstream mediator of TGF-beta, is important in wound healing. We investigated the role of FGF2 in IFN-gamma-induced emphysema and the therapeutic effects of recombinant FGF2 in the prevention of emphysema in a severe non-eosinophilic asthma model. To evaluate the role of FGF2 in IFN-gamma-induced emphysema, lung targeted IFN-gamma transgenic mice were cross-bred with FGF2-deficient mice. A severe non-eosinophilic asthma model was generated by airway application of LPS-containing allergens twice a week for 4 weeks. To evaluate protective effects of FGF2, recombinant FGF2 (10 microg) was injected subcutaneously during allergen challenge in the severe asthma model. We found that non-eosinophilic inflammation and emphysema induced by transgenic overexpression of IFN-gamma in the airways were aggravated by the absence of FGF2. Airway challenge with LPS-containing allergens induced more inflammation in mice sensitized with LPS-containing allergens compared to challenge with allergens alone. In addition, LPS-induced lung inflammation and emphysema depended on IFN-gamma but not on IL-13. Interestingly, emphysema in the severe asthma model was significantly inhibited by treatment with recombinant FGF2 during allergen challenge, whereas lung inflammation was unaffected. Therefore, our present data suggest that FGF2 may help protect against IFN-gamma-induced emphysema, and that recombinant FGF2 may help lessen the severity of emphysema.
Animals ; Asthma/drug therapy/*prevention & control ; Bronchoalveolar Lavage Fluid ; Disease Models, Animal ; Emphysema/drug therapy/*prevention & control ; Enzyme-Linked Immunosorbent Assay ; Fibroblast Growth Factor 2/deficiency/*metabolism/*therapeutic use ; Flow Cytometry ; Inflammation/immunology ; Interferon-gamma/*biosynthesis/genetics ; Interleukin-13 ; Lipopolysaccharides/administration & dosage/pharmacology ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Pulmonary Eosinophilia ; Recombinant Proteins/administration & dosage/therapeutic use

BACKGROUNDIt is widely accepted that tumor necrosis factor-α (TNF-α) plays an important role in the pathogenesis of emphysema. This study aimed at investigating the protective effects of anti-TNF-α antibody, infliximab, in the development of emphysema induced by passive smoking in rats.

METHODSThirty-nine rats were randomly divided into a normal control group (group 1), an emphysema group (group 2), and an infliximab-intervention group (group 3). Rat models of emphysema were established by exposure to cigarette smoking daily for 74 days. After 1 month, the infliximab intervention group was treated with infliximab via subcutaneous injection. The levels of TNF-α, IL-8 and vascular endothelial growth factor (VEGF) in bronchoalveolar lavage fluid (BALF) were measured with enzyme linked immunosorbent assay (ELISA). The number and classification of cells in the BALF were measured. Lung tissue sections stained by hematoxylin and eosin (HE) were observed, and mean linear intercept (MLI) and mean alveolar numbers (MAN) were measured. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) methods were used to examine the percentage of positive cells and distribution of apoptotic cells.

RESULTSThe levels of TNF-α and IL-8 in BALF were higher in group 2 than in group 1 and group 3. The MLI was greater in group 2 than that in group 1 and group 3 while MAN was decreased. The concentration of VEGF in BALF of group 2 was significantly decreased as compared with group 1. The total cells and neutrophils number was significantly increased in group 2 as compared with group 1 and group 3, so was the percentage of neutrophils. The number of TUNEL positive cells in the alveolar septa was significantly increased in group 2 as compared with group 1 and group 3.

CONCLUSIONInfliximab protects against cigarette smoking-induced emphysema by reducing airway inflammation, attenuating alveolar septa cell apoptosis and improving pathological changes.

Animals ; Antibodies, Monoclonal ; therapeutic use ; Bronchoalveolar Lavage Fluid ; chemistry ; cytology ; Infliximab ; Interleukin-8 ; metabolism ; Male ; Pulmonary Alveoli ; cytology ; drug effects ; Pulmonary Emphysema ; chemically induced ; metabolism ; prevention & control ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tobacco Smoke Pollution ; adverse effects ; Tumor Necrosis Factor-alpha ; metabolism