Oxidative damage in alveolar macrophages exposed to cigarette smoke extract and participation of nitric oxide in redox balance.

Nitric oxide (NO) acts in both pathological and biological processes. We investigated the role of NO in the regulation of cigarette smoke-induced oxidative stress in rat alveolar macrophages (RAM). RAM collected from Wistar rats were cultured in 5% concentration cigarette smoke extract (CSE) for 1h. RAM exposed to CSE were then co-incubated with L-NAME (LN), L-arginine (LA), N-acetylcysteine (NAC) and both LN and NAC. RAM cultured only with medium was considered as control group. Biochemical analysis were performed to measure cellular metabolism (MTT), nitrite levels, superoxide dismutase (SOD) and glutathione peroxidase activities, reduced glutathione (GSH) and oxidized (GSSG), malondialdehyde and myeloperoxidase activity. During exposure to CSE, increased NO levels were not only associated with an increase of cell activation, but also affected MTT levels in RAM. CSE exposure resulted in significant redox imbalance in RAM. NAC administration affected SOD antioxidant profile regardless NO levels; however nitrite values were associated with GSH/GSSG ratio. In addition, lipid peroxidation appeared to be nitric-oxide dependent. Furthermore, the use of NAC significantly reduced the expression of NFkB normally observed in RAM exposed to CSE. The present results show that NO appeared to be involved in RAM activation, oxidative status maintenance and lipid peroxidation process during exposure to CSE.

Mate tea reduced acute lung inflammation in mice exposed to cigarette smoke.

OBJECTIVE: Short-term cigarette smoke exposure has been associated with acute lung inflammation (ALI) and oxidative damage. We studied mate tea (Ilex paraguariensis infusion) as a possible nutritional resource for ALI. METHODS: C57BL/6 mice (n = 30) were administered with mate tea orally (150 mg/kg, CSMO), mate tea intraperitonially (150 mg/kg, CSMIP), or the vehicle (CS) and then exposed to cigarette smoke for 5 d (six cigarettes per day). The control group was sham-smoked (n = 30). One day after the final exposure, mice were sacrificed. Bronchoalveolar lavages were performed and lungs removed for biochemical (lung homogenates) and histologic analyses. RESULTS: Mate tea reduced the increase of alveolar macrophages and neutrophils in bronchoalveolar lavages (cells x 10(3)/mL) of the CSMO (214.3 +/- 21.4 and 12.2 +/- 4.9) and CSMIP (248.3 +/- 11.1 and 12.1 +/- 2.3) groups compared with the CS group (425.9 +/- 28.1 and 140.5 +/- 20.1). Mate tea reduced lipid peroxidation (the control group was considered 100%) and tumor necrosis factor-alpha (picograms per milliliter) in the CSMO group (61.3 +/- 11.3 and 185.3 +/- 21.8) compared with the CS group (150.0 +/- 18.1 and 242.3 +/- 13.2). Matrix metalloprotease-9 activity was higher in the CS group and lower in the CSMO group. Oxidative and inflammatory markers in the CSMO group were not different from those in the control group. CONCLUSION: These data imply a potential antioxidant role for mate tea on ALI. Further studies are needed to determine such mechanisms and to explore its potential as an anti-inflammatory and nutritional resource in lung damaged by cigarette smoke exposure.

Light cigarette smoke-induced emphysema and NFkappaB activation in mouse lung.

Light cigarette (LC) exposure is supposed to be less hazardous with a decreased incidence of cancer and tobacco-associated diseases. C57BL/6 mouse groups were subjected to smoke from 3, 6 or 12 LC for 60 days and compared with mice exposed to ambient air (EAA) in order to study lung injury by morphometrical and biochemical methods. Bronchoalveolar lavage (BAL) analysis and histology and stereology were performed. Tissue from the right lung was used for measuring thiobarbituric acid reactive substances (TBARS) and Western blot analysis. One way anova was performed followed by the Student-Newman Keuls post-test (P < 0.05). The cellular content of BAL was 95% alveolar macrophages in all groups except in mice exposed to 3 LC, where 23% neutrophils were observed. Emphysema was not observed in three and 6 LC, but it was found in 12 LC parallel to increased volume density (Vv) of airspaces from 61.0 +/- 0.6 (EAA) to 80.9 +/- 1.0 (12 LC) and decreased Vv of elastic fibres from 17.8 +/- 0.9 (EAA) to 11.8 +/- 0.6 (12 LC). All exposed groups to LC showed low TBARS levels compared with mice EAA. Lung tissue from animals exposed to 12 LC showed decreased tissue inhibitor of metalloprotease-2 and increased matrix metalloprotease-12 detection, which suggests an imbalance in extracellular matrix (ECM). Increased tumour necrosis factor-alpha and nuclear factor-kappaB detection were observed in exposed groups to LC when compared with mice EAA. The data suggest that LC is so dangerous to lungs as full-flavour cigarettes inducing ECM imbalance and emphysema.

Design, synthesis and antiinflammatory activity of novel phthalimide derivatives, structurally related to thalidomide.

As part of an ongoing effort to develop new thalidomide analogues as antiinflammatory lead-candidates, this paper describes the synthesis and antiinflammatory activity of novel N-phenyl-phthalimide functionalized derivatives (4a-d, 5a,b, 6a,b). The target compounds were assayed in an acute lung inflammatory model and all compounds were able to inhibit TNF-alpha production and subsequent neutrophil recruitment in the LPS-acute lung inflammatory model.

Inhibition of interleukin-1beta reduces mouse lung inflammation induced by exposure to cigarette smoke.

We examined nuclear factor kappaB activation, release of inflammatory mediators and cellular infiltration in acute cigarette smoke inflammation models. One hour after exposure to one puff of cigarette smoke, alveolar macrophages from bronchoalveolar lavage (BAL) fluid of C57BL/6J mice showed an increased activity of nuclear factor kappaB-DNA binding but similar numbers as compared to that of BAL fluid from mice exposed to ambient air. Exposure to 1 cigarette/day for 1, 4 or 7 days led to an increase in interleukin-1beta and monocyte chemoattractant protein-1 levels and to a progressive influx of nuclear factor kappaB-activated alveolar macrophages into the BAL fluid and lung tissue. Exposure to 2 cigarettes/day for 7 days led to a significant increase in interleukin-1beta levels accompanied by a massive alveolar macrophage influx into the BAL fluid. Tumor necrosis factor-alpha levels and subsequent neutrophil influx were only detected after exposure to 4 or 8 cigarettes/day for 7 days. Treatment of mice with an antibody anti-interleukin-1beta during cigarette smoke exposure for 7 days significantly reduced both interleukin-1beta levels and alveolar macrophage influx. These data show that a single exposure to cigarette smoke rapidly activates alveolar macrophages, inducing the production of interleukin-1beta, which may play an important role in triggering chronic cigarette smoke-mediated lung inflammation.