Prophylactic anti-inflammation inhibits cigarette smoke-induced emphysema in guinea pigs

Abstract

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, im, 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 (L_m): 120.6±16.0 μm in Group a: 89.8±9.2 μm in Group B and 102.4±17.7 μm in Group C. The average L_m 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 μm) 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.

Keywords

cigarette smoke / pulmonary emphysema / prophylactic anti-inflammation

References

[1] AnthonisenN R, ConnettJ E, KileyJ P, et al.. Effects of smoking intervention and the use of an inhaled anticholinergic bronchodilator on the rate of decline of FEV1. The Lung Health Study. JAMA, 1994, 272: 1497-1497

[2] WardS A, CasaburiR. 21st century perspective on chronic obstructive pulmonary disease. Respiration, 2001, 68: 557-61

[3] ChurgA, DaiJ, TaiH, et al.. Tumor necrosis factor-alpha is central to acute cigarette smoke-induced inflammation and connective tissue breakdown. Am J Respir Crit Care Med, 2002, 166: 849-849

[4] QuenterC A, CoalsonJ J, JacquesJ. Emphysema associated with intravascular leukocyte sequenstration. Am Rev Repir Dis, 1981, 123: 79-79

[5] KawakamiM, PaulL, ThurlbeckW M. The effect of age on lung structure in male BALB/cNNia inbred mice. Am J Anat, 1984, 170: 1-1

[6] ThurlbeckW M. Internal surface area of nonemphysematous lungs. Am Rev Respir Dis, 1967, 95: 765-765

[7] WrightJ L, ChurgA. Cigarette smoke causes physiologic and morphologic changes of emphysema in the guinea pig. Am Rev Repir Dis, 1990, 142: 1422-1422

[8] SniderG L, KleinermanJ, ThurlbeckW M, et al.. The definition of emphysema: report of a National Heart, Lung, and Blood Institute Division of Lung Diseases Workshop. Am Rev Respir Dis, 1985, 132: 182-182

[9] American Thoracic Society. Standards for the diagnosis and care of patients with chronic obstructive pulmonary disease. Am J Repir Crit Care Med, 1995, 152: 77-77

[10] EscolarJ D, MartinezM N, EscolarM A, et al.. Tobacco smoke and age as risk factors in emphysema. Morphometrical study on the rat. Histol Histopathol, 1996, 11: 7-7

[11] EhrhartI, McCloudL, CreamerK M, et al.. Pentoxifylline markedly reduces pulmonary neutrophil sequestration. Chest, 1999, 116(1 Suppl): 34S

[12] WilliamsJ H, HeshmatiS, TamadonS, et al.. Inhibition of alveolar macrophages by pentoxifylline. Crit Care Med, 1991, 19: 1073-1073

[13] PoulakisN, AndroutsosG, KaziD, et al.. The differential effect of pentoxifylline on cytokine production by alveolar macrophages and its clinical implications. Respir Med, 1999, 93: 52-52

[14] EntzianP, Bitter-SuermannS, BurdonD, et al.. Differences in the anti-inflammatory effects of theophylline and pentoxifylline: important for the development of asthma therapy?. Allergy, 1998, 53: 749-749

[15] SerafinW E. HardmanJG, LimbirdLE. Methylxanthines. Goodman & Gilmam’s The pharmacological basis of therapeutics, 19969th ed.New York, McGraw-Hill: 672-682