Immunomodulatory effects of the tobacco-specific carcinogen, NNK, on alveolar macrophages

An update on the formation in tobacco, toxicity and carcinogenicity of N'-nitrosonornicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone

The tobacco-specific nitrosamines N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) are considered 'carcinogenic to humans' by the International Agency for Research on Cancer (IARC) and are believed to be important in the carcinogenic effects of both smokeless tobacco and combusted tobacco products. This short review focuses on the results of recent studies on the formation of NNN and NNK in tobacco, and their carcinogenicity and toxicity in laboratory animals. New mechanistic insights are presented regarding the role of dissimilatory nitrate reductases in certain microorganisms involved in the conversion of nitrate to nitrite that leads to the formation of NNN and NNK during curing and processing of tobacco. Carcinogenicity studies of the enantiomers of the major NNK metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and the enantiomers of NNN are reviewed. Recent toxicity studies of inhaled NNK and co-administration studies of NNK with formaldehyde, acetaldehyde, acrolein and CO2, all of which occur in high concentrations in cigarette smoke, are discussed.

Tobacco use and risk of acute stroke in 32 countries in the INTERSTROKE study: a case-control study

Background

Smoking is a major risk factor for the global burden of stroke. We have previously reported a global population attributable risk (PAR) of stroke of 12.4% associated with current smoking. In this study we aimed to explore the association of current tobacco use with different types of tobacco exposure and environmental tobacco smoke (ETS) exposure on the risk of stroke and stroke subtypes, and by regions and country income levels.

Methods

The INTERSTROKE study is a case-control study of acute first stroke and was undertaken with 13,462 stroke cases and 13,488 controls recruited between January 11, 2007 and August 8, 2015 in 32 countries worldwide. Association of risk of tobacco use and ETS exposure were analysed with overall stroke, ischemic and intracerebral hemorrhage (ICH), and with TOAST etiological stroke subtypes (large vessel, small vessel, cardioembolism, and undetermined).

Findings

Current smoking was associated with an increased risk of all stroke (odds ratio [OR] 1.64, 95% CI 1.46-1.84), and had a stronger association with ischemic stroke (OR 1.85, 95% CI 1.61-2.11) than ICH (OR 1.19 95% CI 1.00-1.41). The OR and PAR of stroke among current smokers varied significantly between regions and income levels with high income countries (HIC) having the highest odds (OR 3.02 95% CI 2.24-4.10) and PAR (18.6%, 15.1-22.8%). Among etiological subtypes of ischemic stroke, the strongest association of current smoking was seen for large vessel stroke (OR 2.16, 95% CI 1.63-2.87) and undetermined cause (OR 1.97, 95% CI 1.55-2.50). Both filtered (OR 1.73, 95% CI 1.50-1.99) and non-filtered (OR 2.59, 95% CI 1.79-3.77) cigarettes were associated with stroke risk. ETS exposure increased the risk of stroke in a dose-dependent manner, exposure for more than 10 h per week increased risk for all stroke (OR 1.95, 95% CI 1.69-2.27), ischemic stroke (OR 1.89, 95% CI 1.59-2.24) and ICH (OR 2.00, 95% CI 1.60-2.50).

Interpretation

There are significant variations in the magnitude of risk and PAR of stroke according to the types of tobacco used, active and ETS exposure, and countries with different income levels. Specific strategies to discourage tobacco use by any form and to build a smoke free environment should be implemented to ease the global burden of stroke.

Funding

The Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Canadian Stroke Network, Swedish Research Council, Swedish Heart and Lung Foundation, The Health & Medical Care Committee of the Regional Executive Board, Region Västra Götaland, and through unrestricted grants from several pharmaceutical companies with major contributions from Astra Zeneca, Boehringer Ingelheim (Canada), Pfizer (Canada), MERCK, Sharp and Dohme, Swedish Heart and Lung Foundation, UK Chest, and UK Heart and Stroke.

The Expression of the Alpha7 Nicotinic Acetylcholine Receptor and the Effect of Smoking in Curdlan-Administered SKG Mice

Nicotine, an abundant molecule in tobacco, has immunomodulatory effects on inflammatory diseases, primarily due to the activation of alpha7 nicotinic acetylcholine receptor (α7 nAChR). We aim to evaluate the expression of the α7 nAChR+ cells in joint tissue and the effect of smoking on immune cells and peripheral arthritis in curdlan-administered SKG mice, a murine model of spondyloarthropathy (SpA). The SKG mice were injected with curdlan two times at 2-week intervals and were divided into two groups; one exposed to cigarette smoke and the other not exposed. We found that the α7 nAChR+ cells increased in the joint tissue of curdlan-administered SKG mice compared to in the wild type. Furthermore, the peripheral arthritis scores and histological scores for synovial inflammation were lower in smoke-exposed curdlan-administered SKG mice than in mice not exposed to smoke. Immunofluorescence staining of the α7 nAChR+ and IL-17A+ cells was lower in the synovia of smoke-exposed mice than the control mice. The proportions of α7 nAChR+IL-17A+ and α7 nAChR+IL-17A+FOXP3+ cells also decreased in the synovia of smoke-exposed mice compared with the controls. We observed an increase in the α7 nAChR+ cells within the joint tissue of curdlan-administered SKG mice and that cigarette smoke had an influence on both peripheral arthritis and immune cell population, especially α7 nAChR+ cells. Thus, exposure to cigarette smoke after arthritogenic stimuli may have an anti-arthritogenic effect in curdlan-administered SKG mice.

Acrolein Increases the Pulmonary Tumorigenic Activity of the Tobacco-Specific Nitrosamine 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

Tobacco smoke is a complex mixture of more than 7000 chemicals, of which many are toxic and/or carcinogenic. Many hazard assessments of tobacco have focused on individual chemical exposures without consideration of how the chemicals may interact with one another. Two chemicals, the human carcinogen 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK) and a possible human carcinogen, acrolein, were hypothesized to interact with one another, possibly owing to the additive effects of DNA adduct formation or influence on the repair of mutagenic DNA adducts. To test our hypothesis that coexposure to NNK and acrolein is more carcinogenic than either chemical alone, A/J mice were exposed to NNK (i.p., 0, 2.5, or 7.5 μmol in saline) in the presence or absence of inhaled acrolein (15 ppmV). While the single 3 h exposure to acrolein alone did not induce lung adenomas, it significantly enhanced NNK's lung carcinogenicity. In addition, mice receiving both NNK and acrolein had more adenomas with dysplasia or progression than those receiving only NNK, suggesting that acrolein may also increase the severity of NNK-induced lung adenomas. To test the hypothesis that the interaction was due to effects on DNA adduct formation and repair, NNK- and acrolein pulmonary DNA adduct levels were assessed. There was no consistent effect of the coexposure on NNK-derived DNA adducts, and acrolein DNA adducts were not elevated above endogenous levels. This study supports the hypothesis that tobacco smoke chemicals combine to contribute to the carcinogenic potency of tobacco smoke, and the mechanism of interaction cannot be explained by alterations of DNA adduct levels.

The role of macrophage polarization and function in environmental toxicant-induced cancers

Macrophages are a critical member of the innate immune system and can intensify tumor invasiveness and assist the growth of neoplastic cells. Moreover, they have the capability to reinforce immunosuppression and angiogenesis. Various investigations suggest that health-related issues, including inflammatory disorders and neoplastic diseases may be caused by environmental toxicant exposure. However, it is still unclear what role these environmental toxicants play in causing carcinogenesis by disturbing the mechanisms of migration, polarization, differentiation, and immune-stimulatory functions of macrophages. Accordingly, in this article, we will explore the interaction between environmental chemicals and inflammatory macrophage processes at the molecular level and their association with tumor progression and carcinogenesis.

Regulatory function of peroxiredoxin I on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced lung cancer development

Smoking is a major cause of lung cancer, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of the most important carcinogens in cigarette smoke. NNK modulates the expression of peroxiredoxin (Prdx) I in lung cancer. Prdx1 is upregulated in lung squamous cell carcinoma and lung adenocarcinoma, and considered a potential biomarker for lung cancer. The current article reviewed the role and regulatory mechanisms of Prdx1 in NNK-induced lung cancer cells. Prdx1 protects erythrocytes and DNA from NNK-induced oxidative damage, prevents malignant transformation of cells and promotes cytotoxicity of natural killer cells, hence suppressing tumor formation. In addition, Prdx1 has the ability to prevent NNK-induced lung tumor metabolic activity and generation of large amount of reactive oxygen species (ROS) and ROS-induced apoptosis, thus promoting tumor cell survival. In contrast to this, Prdx1, together with NNK, can promote the epithelial-mesenchymal transition and migration of lung tumor cells. The signaling pathways associated with NNK and Prdx1 in lung cancer cells have been discussed in present review; however, numerous potential pathways are yet to be studied. To develop novel methods for treating NNK-induced lung cancer, and improve the survival rate of patients with lung cancer, further research is needed to understand the complete mechanism associated with NNK.

Carcinogenesis: Failure of resolution of inflammation?

Inflammation in the tumor microenvironment is a hallmark of cancer and is recognized as a key characteristic of carcinogens. However, the failure of resolution of inflammation in cancer is only recently being understood. Products of arachidonic acid and related fatty acid metabolism called eicosanoids, including prostaglandins, leukotrienes, lipoxins, and epoxyeicosanoids, critically regulate inflammation, as well as its resolution. The resolution of inflammation is now appreciated to be an active biochemical process regulated by endogenous specialized pro-resolving lipid autacoid mediators which combat infections and stimulate tissue repair/regeneration. Environmental and chemical human carcinogens, including aflatoxins, asbestos, nitrosamines, alcohol, and tobacco, induce tumor-promoting inflammation and can disrupt the resolution of inflammation contributing to a devastating global cancer burden. While mechanisms of carcinogenesis have focused on genotoxic activity to induce mutations, nongenotoxic mechanisms such as inflammation and oxidative stress promote genotoxicity, proliferation, and mutations. Moreover, carcinogens initiate oxidative stress to synergize with inflammation and DNA damage to fuel a vicious feedback loop of cell death, tissue damage, and carcinogenesis. In contrast, stimulation of resolution of inflammation may prevent carcinogenesis by clearance of cellular debris via macrophage phagocytosis and inhibition of an eicosanoid/cytokine storm of pro-inflammatory mediators. Controlling the host inflammatory response and its resolution in carcinogen-induced cancers will be critical to reducing carcinogen-induced morbidity and mortality. Here we review the recent evidence that stimulation of resolution of inflammation, including pro-resolution lipid mediators and soluble epoxide hydrolase inhibitors, may be a new chemopreventive approach to prevent carcinogen-induced cancer that should be evaluated in humans.

Nicotine exposure impairs germ cell development in human fetal ovaries cultured in vitro

In the present paper, we found that human fetal ovaries (at ~16 weeks) express the transcripts for several subunits of the nicotinic acetylcholine receptor (nAChR). Exposure to the drug in vitro resulted in the marked increase of apoptosis in the ovaries in a time and dose-dependent manner. Evidence that adverse nicotine effects are potentially due to an increased level of reactive oxygen species (ROS) and consequent DNA damage, both in the ovarian somatic cells and germ cells, are reported. After 4 days of culture, exposure to 1 mM and 10 mM nicotine caused a 50% and 75% decrease, respectively, in the number of oogonia/oocytes present in the fetal ovaries. These results represent the first indication that nicotine may directly cause apoptosis in cells of the fetal human ovary and may lead to a reduction of the ovarian reserve oocytes and consequent precocious menopause in mothers smoking during pregnancy.

Cigarette toxin 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) induces experimental pancreatitis through α7 nicotinic acetylcholine receptors (nAChRs) in mice

Clinical studies have shown that cigarette smoking is a dose-dependent and independent risk factor for acute pancreatitis. Cigarette smoke contains nicotine which can be converted to the potent receptor ligand and toxin, NNK [4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone]. Previously, we have shown that NNK induces premature activation of pancreatic zymogens in rats, an initiating event in pancreatitis, and this activation is prevented by pharmacologic inhibition of nicotinic acetylcholine receptors (nAChR). In this study, we determined whether NNK mediates pancreatitis through the α7 isoform of nAChR using α7nAChR knockout mice. PCR analysis confirmed expression of non-neuronal α7nAChR in C57BL/6 (WT) mouse and human acinar cells. NNK treatment stimulated trypsinogen activation in acini from WT but not α7nAChR-/- mice. NNK also stimulated trypsinogen activation in human acini. To further confirm these findings, WT and α7nAChR-/- mice were treated with NNK in vivo and markers of pancreatitis were measured. As observed in acini NNK treatment induced trypsinogen activation in WT but not α7nAChR-/- mice. NNK also induced other markers of pancreatitis including pancreatic edema, vacuolization and pyknotic nuclei in WT but not α7nAChR-/- animals. NNK treatment led to increased neutrophil infiltration, a marker of inflammation, in WT mice and to a significantly lesser extent in α7nAChR-/- mice. We also examined downstream targets of α7nAChR activation and found that calcium and PKC activation are involved down stream of NNK stimulation of α7nAChR. In this study we used genetic deletion of the α7nAChR to confirm our previous inhibitor studies that demonstrated NNK stimulates pancreatitis by activating this receptor. Lastly, we demonstrate that NNK can also stimulate zymogen activation in human acinar cells and thus may play a role in human disease.

Effect of a 12-week submaximal swimming training in rats exposed to tobacco- derived nitrosamine ketone

Background

Tobacco contains carcinogens such as NNK (nicotine-derived nitrosamine ketone) that makes induction of lung cancer by changing the stimulation of IL-10 expression. The aim of this study was to investigate changes in resting levels of IL-10 in lung tissues of rats exposed to NNK after a 12-week aerobic submaximal swimming training.

Methods

For this purpose, 46 Wistar rats were randomly divided into five groups consisting training, training + NNK, NNK, saline and control. NNK-induced groups received NNK subcutaneously one day per week at a rate of 12/5 mg per kg body weight and the training groups performed submaximal swimming training for 12 weeks. The levels of IL-10 in homogenized lung tissue were measured by ELISA.

Results

Findings indicated that a period of swimming training increased the IL-10 levels significantly in lung tissue of training group when compared to control (P=0.00) and NNK groups (P=0.00). Also, a significant increase of IL-10 level was observed in exercise + NNK group when compared to NNK group (p≤0/02). Furthermore, it was observed that IL-10 levels of NNK group had a significant decrease when compared to training group (P=0/00), training + NNK group (p≤0/02), but had insignificant increase when compared to saline group (p≤0/85).

Conclusions

Generally, it could be confirmed that regular submaximal aerobic training plays an important role in the inhibition of the effects of lung inflammation induced by NNK via increasing IL-10 activity.

Flaxseed Consumption Inhibits Chemically Induced Lung Tumorigenesis and Modulates Expression of Phase II Enzymes and Inflammatory Cytokines in A/J Mice

Flaxseed consumption is associated with reduced oxidative stress and inflammation in lung injury models and has shown anticancer effects for breast and prostate tissues. However, the chemopreventive potential of flaxseed remains unexplored for lung cancer. In this study, we investigated the effect of flaxseed on tobacco smoke carcinogen (NNK)-induced lung tumorigenesis in an A/J mouse model. Mice exposed to NNK were fed a control diet or a 10% flaxseed-supplemented diet for 26 weeks. Flaxseed-fed mice showed reduced lung tumor incidence (78%) and multiplicity, with an average of 2.7 ± 2.3 surface lung tumor nodules and 1.0 ± 0.9 H&E cross-section nodules per lung compared with the control group, which had 100% tumor incidence and an average of 10.2 ± 5.7 surface lung tumor nodules and 3.9 ± 2.6 H&E cross-section nodules per lung. Furthermore, flaxseed-fed mice had a lower incidence of adenocarcinomas compared with control-fed mice. Western blotting performed on normal lung tissues showed flaxseed suppressed phosphorylation (activation) of p-AKT, p-ERK, and p-JNK kinases. RNA-Seq data obtained from normal lung and lung tumors of control and flaxseed-fed mice suggested that flaxseed intake resulted in differential expression of genes involved in inflammation-mediated cytokine signaling (IL1, 6, 8, 9, and 12α), xenobiotic metabolism (several CYPs, GSTs, and UGTs), and signaling pathways (AKT and MAPK) involved in tumor cell proliferation. Together, our results indicate that dietary flaxseed supplementation may be an effective chemoprevention strategy for chemically induced lung carcinogenesis by altering signaling pathways, inflammation, and oxidative stress. Cancer Prev Res; 11(1); 27-37. ©2017 AACR.

Tobacco Smoking as a Risk Factor for Increased Antibiotic Prescription

INTRODUCTION

Antibiotic resistance is rapidly spreading, affecting millions of people and costing billions of dollars. Potential factors affecting antibiotic prescription, such as tobacco use, could dramatically influence this public health crisis. The study determined the magnitude of impact that tobacco use has on antibiotic prescribing patterns.

METHODS

Pooled data were analyzed in 2015 from the 2006-2010 National Ambulatory Medical Care Survey, a cross-sectional survey describing use of ambulatory medical services in the U.S. via healthcare provider-patient encounters. Patients aged >18 years with documented tobacco use status diagnosed with an infection were included (i.e., all encounters in the analysis included an infectious diagnosis of interest). The analytic sample included 8,307 visits, representing 294 million visits nationally.

RESULTS

Half (49.9%) of encounters that included any infection had an antibiotic prescribed. Adjusted odds of receiving antibiotics among current tobacco users was 1.20 (95% CI=1.02, 1.42), and even higher for encounters of respiratory infections (AOR=1.31, 95% CI=1.05, 1.62). Antibiotic prescription rates were lower among patients aged >65 years, those with comorbid asthma or cancer, non-whites, and those covered by Medicaid and higher for primary care physicians.

CONCLUSIONS

Despite lack of evidence-based rationale, among a national sample of patients with an infectious diagnosis, tobacco users had 20%-30% higher odds of receiving antibiotics than non-tobacco users. This is the first U.S. study to quantify the magnitude of this unsubstantiated practice. Prescribers should understand that tobacco use could be associated with higher antibiotic prescription, which may subsequently increase antimicrobial resistance in the community.

Hypersensitivity pneumonitis : a broader perspective

Hypersensitivity pneumonitis (HP) represents a group of lung disorders caused by the inhalation of a wide variety of organic particles by susceptible individuals. HP occurs mainly in nonsmokers, but smoking may promote an insidious and chronic disease. The prevalence of HP is difficult to estimate accurately since several antigens can produce the disease, but the range spans infancy to old age. Regardless of the causative antigen or its environmental setting, the clinical manifestations are essentially the same. Three different clinical presentations have been recognized: acute, subacute, and chronic. In the acute form, patients show flu-like symptomatology, followed by dyspnea and dry cough. Symptoms subside a few hours or days later. The subacute and chronic forms result from recurrent low-level antigen exposure and are characterized by progressive dyspnea and dry cough. Other constitutional symptoms such as fatigue, anorexia, and weight loss can be apparent. Fever may occur in the subacute form. Importantly, chronic HP may evolve insidiously or may result from repeated acute/subacute episodes. Recurrent acute, subacute, and chronic HP may progress to irreversible lung fibrosis or provoke emphysematous changes.HP can be difficult to identify, and precise diagnosis requires a history of exposure and a constellation of clinical, imaging, laboratory, bronchoalveolar lavage and pathologic findings. General laboratory tests show an increase of acute phase reactants. Specific precipitating antibodies, when present, are evidence of antigen exposure, and are a hallmark for diagnosis. Chest radiograph usually reveals widespread ground-glass attenuation, and nodular or reticulonodular shadowing. High-resolution CT features include diffuse or patchy ground-glass opacities with small poorly defined nodules and air trapping. Pulmonary function tests are characterized by a predominantly restrictive ventilatory defect with loss of lung volume and hypoxemia at rest that worsens with exercise. Bronchoalveolar lavage reveals a significant increase in lymphocytes, mostly over 40%. In the acute form there is also an increase in neutrophils. Antigen-induced lymphocyte proliferation, and environmental or laboratory-controlled inhalation challenge, may be used for diagnostic purposes and can help to establish a diagnosis of insidious forms of HP. In subacute or chronic cases, lung biopsy may be necessary. Typical findings include bronchiolitis, lymphocytic alveolitis, and loosely formed granulomas, although occasionally other morphologic patterns such as nonspecific interstitial pneumonia may exist. Treatment focuses on avoiding further exposure to the offending antigen(s). Corticosteroids are recommended in subacute and chronic forms. The usual regimen consists of initial high doses of systemic corticosteroid (e.g. prednisone 0.5-1.0 mg/kg/day), followed by gradual tapering.

The effect of environmental chemicals on the tumor microenvironment

Potentially carcinogenic compounds may cause cancer through direct DNA damage or through indirect cellular or physiological effects. To study possible carcinogens, the fields of endocrinology, genetics, epigenetics, medicine, environmental health, toxicology, pharmacology and oncology must be considered. Disruptive chemicals may also contribute to multiple stages of tumor development through effects on the tumor microenvironment. In turn, the tumor microenvironment consists of a complex interaction among blood vessels that feed the tumor, the extracellular matrix that provides structural and biochemical support, signaling molecules that send messages and soluble factors such as cytokines. The tumor microenvironment also consists of many host cellular effectors including multipotent stromal cells/mesenchymal stem cells, fibroblasts, endothelial cell precursors, antigen-presenting cells, lymphocytes and innate immune cells. Carcinogens can influence the tumor microenvironment through effects on epithelial cells, the most common origin of cancer, as well as on stromal cells, extracellular matrix components and immune cells. Here, we review how environmental exposures can perturb the tumor microenvironment. We suggest a role for disrupting chemicals such as nickel chloride, Bisphenol A, butyltins, methylmercury and paraquat as well as more traditional carcinogens, such as radiation, and pharmaceuticals, such as diabetes medications, in the disruption of the tumor microenvironment. Further studies interrogating the role of chemicals and their mixtures in dose-dependent effects on the tumor microenvironment could have important general mechanistic implications for the etiology and prevention of tumorigenesis.

Tobacco smoke induces production of chemokine CCL20 to promote lung cancer

Tobacco kills nearly 6 million people each year, and 90% of the annual 1.59 million lung cancer deaths worldwide are caused by cigarette smoke. Clinically, a long latency is required for individuals to develop lung cancer since they were first exposed to smoking. In this study, we aimed to identify clinical relevant inflammatory factors that are critical for carcinogenesis by treating normal human lung epithelial cells with tobacco carcinogen nicotine-derived nitrosaminoketone (NNK) for a long period (60 days) and systematic screening in 84 cytokines/chemokines. We found that a chemokine CCL20 was significantly up-regulated by NNK, and in 78/173 (45.1%) patients the expression of CCL20 was higher in tumor samples than their adjacent normal lung tissues. Interestingly, CCL20 was up-regulated in 48/92 (52.2%) smoker and 29/78 (37.2%) nonsmoker patients (p = 0.05), and high CCL20 was associated with poor prognosis. NNK induced the production of CCL20, which promoted lung cancer cell proliferation and migration. In addition, an anti-inflammation drug, dexamethasone, inhibited NNK-induced CCL20 production and suppressed lung cancer in vitro and in vivo. These results indicate that CCL20 is crucial for tobacco smoke-caused lung cancer, and anti-CCL20 could be a rational approach to fight against this deadly disease.

Suppressive oligodeoxynucleotides reduce lung cancer susceptibility in mice with silicosis

Silicosis is an inflammatory lung disease induced by the inhalation of silica-containing dust particles. There is conflicting data on whether patients with silicosis are more susceptible to lung cancer induced by cigarette smoke. To examine this issue experimentally, a model was developed in which one of the most abundant and potent carcinogens present in cigarette smoke [4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK)] was administered to mice at the peak of silica-induced pulmonary inflammation. Results show that the incidence of lung tumors in silicotic mice treated with NNK was significantly increased compared with mice exposed to silica or NNK alone. Synthetic oligonucleotides (ODN) containing repetitive TTAGGG motifs can block pathologic inflammation. We therefore examined whether treatment with these suppressive (Sup) ODN could block silica-induced pulmonary inflammation and thereby reduce susceptibility to lung cancer. Results show that Sup (but not control) ODN inhibit pulmonary fibrosis and other inflammatory manifestations of chronic silicosis. Of greater import, Sup ODN reduced lung tumor incidence and multiplicity in silicotic mice exposed to NNK. These findings establish an experimental model for examining the role of silicotic inflammation in cancer susceptibility and demonstrate that Sup ODN represent a novel therapy for chronic silicosis.

Sino-nasal outcome test (SNOT-22): a predictor of postsurgical improvement in patients with chronic sinusitis

BACKGROUND

A number of factors are critical when considering the expected benefit of surgical intervention in patients with chronic rhinosinusitis (CRS) who have failed medical therapy.

OBJECTIVE

To evaluate the Sino-nasal Outcome Test (SNOT-22) and other patient demographic characteristics as predictors of postsurgical improvement in patients with CRS.

METHODS

Consecutive adult subjects presenting to the Otolaryngology Clinics at the University of Virginia with refractory CRS that required surgery were included. Patients were excluded if they had not completed both preoperative and postoperative SNOT-22 evaluations. Demographic and baseline measures, including asthma and smoking status, total immunuglobulin E (IgE), absolute eosinophil counts, and Lund-Mackay computed tomography (CT) scoring were also obtained for each subject. Regression analyses were performed.

RESULTS

One hundred four subjects met criteria and were included. These subjects showed a 51% overall improvement in postsurgical SNOT-22 evaluations (95% confidence interval [CI]: [45, 57%], P < .001). Multivariate regression analysis revealed that SNOT-22 items related to "runny nose," "cough," and "sadness" were independent predictors of postsurgical SNOT-22 improvement (P < .05, for all). Although "runny nose" had a direct correlation with improvement, more severe "sadness" and "cough" scores had a negative impact on degree of improvement. Similarly, analyses indicated that questions categorized as pertaining to nasal or ear symptoms were uniquely associated with postsurgical improvement in SNOT-22 scores (P < .001 and P = .015, respectively). Neither Lund-Mackay CT scoring, total IgE, nor absolute eosinophil counts correlated with improvement in postsurgical SNOT-22 scores.

CONCLUSION

Physicians can use components of the SNOT-22 to predict likelihood of symptom improvement after surgical intervention in subjects with CRS.

New molecular insights in tobacco-induced lung cancer

We know that cigarette smoking is a leading preventable cause of carcinogenesis in lung cancer. Cigarette smoke is a mixture of more than 5000 chemical compounds, among which more than 60 are recognized to have a specific carcinogenic potential. Carcinogens and their metabolites (i.e., N-nitrosamines and polycyclic aromatic hydrocarbons) can activate multiple pathways, contributing to lung cell transformation in different ways. Nicotine, originally thought only to be responsible for tobacco addiction, is also involved in tumor promotion and progression with antiapoptotic and indirect mitogenic properties. Lung nodules are frequent in smokers and can be transformed into malignant tumors depending on persistant smoking status. Even if detailed mechanisms underlying tobacco-induced cancerogenesis are not completely elucitated, this report collects the emergent body of knowledge in order to simplify the extremely complex framework that links smoking exposure to lung cancer.

Analysis of the Roles of Smoking and Allergy in Nasal Polyposis

Objectives:

Recent studies on the etiopathogenesis of nasal polyps have shown that smoking and nonallergenic inhalants such as occupational dust exposure cause chronic inflammation of the nasal mucosa. These factors may be associated with nasal polyps. The aim of this study was to use laboratory tests to investigate the effects of smoking and allergens on the development of nasal polyps.

Methods:

The study included 60 consecutive patients with a diagnosis of nasal polyposis who were treated with functional endoscopic sinus surgery at our clinic and 25 smoker and 25 nonsmoker participants who constituted a control group.

Results:

In the patient and control groups, the mean absorbance value for cotinine in smokers was found to be statistically significantly lower than that in nonsmokers. There was a significant difference between the groups with respect to blood cotinine positivity. No significant difference was found between the groups in terms of allergy parameters. In the regression model, smoking was found to be the only significant risk factor for the development of nasal polyps, independent of smoking duration, absorbance value, or cotinine positivity.

Conclusions:

Smoking restriction and avoiding exposure to cigarette smoke by patients with nasal polyps may be an important strategy in the prevention and recurrence of nasal polyposis. No direct relationship was determined between allergy and nasal polyposis.

Smoking and endoscopic sinus surgery: does smoking volume contribute to clinical outcome

BACKGROUND

The effect of tobacco smoking on chronic rhinosinusitis (CRS) is not yet well-delineated. The purpose of this investigation was to evaluate the overall effect of smoking on postoperative outcomes (endoscopic score and health-related quality-of-life [HRQoL]) after endoscopic sinus surgery (ESS) for CRS and to determine if volume of daily smoking impacts outcomes.

METHODS

A total of 784 patients with CRS were prospectively enrolled between January 2001 and April 2009 after electing ESS from 1 of 3 academic tertiary care centers. Follow-up longer than 6 months was available on 39 smoking patients. Smoking volume (cigarettes/day) analysis was performed by dichotomizing patients into either of 2 subgroups: light smokers (<20 cigarettes per day) or heavy smokers (≥ 20 cigarettes per day). Primary outcomes were Lund-Kennedy endoscopy scores and 2 disease-specific HRQoL instruments: the Rhinosinusitis Disability Index (RSDI) and Chronic Sinusitis Survey (CSS).

RESULTS

Smokers and nonsmokers experienced similar improvement in HRQoL following surgery (RSDI: p = 0.792 and CSS: p = 0.117). No difference in HRQoL improvements between light smokers and heavy smokers was identified. While overall changes in endoscopy scores did not differ between smokers and nonsmokers, there was a significant difference in the prevalence of worsening postoperative endoscopy scores between heavy smokers, light smokers, and nonsmokers (100%, 33%, and 20%, respectively; p = 0.002).

CONCLUSION

Active smoking status does not alter postoperative improvement in HRQoL after ESS. Although limited by a small sample size, increasing smoking volume may contribute to worse postoperative endoscopy scores.

Fabrication of ellagic acid incorporated self-assembled peptide microtubes and their applications

Ellagic acid (EA), a plant polyphenol known for its wide-range of health benefits was encapsulated within self-assembled threonine based peptide microtubes. The microtubes were assembled using the synthesized precursor bolaamphiphile bis(N-α-amido threonine)-1,5-pentane dicarboxylate. The self-assembly of the microstructures was probed at varying pH. In general, tubular formations were observed at a pH range of 4-6. The formed microtubes were then utilized for fabrication with EA. We probed the ability of the microtubes as drug release vehicles for EA as well as for antibacterial applications. It was found that the release of EA was both pH and concentration dependent. The biocompatibility as well as cytotoxicity of the EA-fabricated microtubes was examined in the presence of mammalian normal rat kidney (NRK) cells. Finally the antibacterial effects of the EA incorporated peptide microtubes was examined against Escherichia coli and Staphylococcus aureus.

Ellagic acid promoted biomimetic synthesis of shape-controlled silver nanochains

In this work, ellagic acid (EA), a naturally occurring plant polyphenol, was utilized for the biomimetic synthesis of silver (Ag) nanoparticles, which over a period of time formed extended branched nanochains of hexagonal-shaped silver nanoparticles. It was found that EA not only has the capability of reducing silver ions, resulting in the formation of Ag nanoparticles, due to its extended polyphenolic system, but also appears to recognize and affect the Ag nanocrystal growth on the (111) face, leading to the formation of hexagon-shaped Ag nanocrystals. Initially, various Ag nanocrystal shapes were observed; however, over a longer period of time, a majority of hexagonal-shaped nanocrystals were formed. Although the exact mechanism of formation of the nanocrystals is not known, it appears that EA attaches to the silver nuclei, leading to lower surface energy of the (111) face. Further, the nanocrystals fuse together, forming interfaces among the aggregates, and, with time, those interfaces become lesser, and the nanoparticles merge together and share the same single crystallographic orientation, which leads to the formation of long elongated chains of hexagonal nanoparticles. This biomimetic approach may be developed as a green synthetic method to prepare building blocks with tunable properties for the development of nanodevices. Further, we explored the antibacterial properties and found that the tandem of EA-Ag nanochains substantially enhanced the antibacterial properties of both gram-positive and gram-negative bacteria compared to silver nanoparticles or EA alone. Additionally, the materials were also utilized for imaging of mammalian NRK (normal rat kidney) cells.

Tobacco carcinogen NNK transporter MRP2 regulates CFTR function in lung epithelia: implications for lung cancer

Lung cancer is the leading cause of cancer death in the United States. About 85% of all lung cancers are linked to tobacco smoke, in which more than 50 lung carcinogens have been identified and one of the most abundant is 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The human lung epithelium constitutes the first line of defense against tobacco-specific carcinogens, in which apically-localized receptors, transporters, and ion channels in the airway may play a critical role in this native defense against tobacco smoke. Here we showed that multidrug resistance protein-2 (MRP2) and cystic fibrosis transmembrane conductance regulator (CFTR), two ATP-binding cassette (ABC) transporters, are localized to the apical surfaces of plasma membrane in polarized lung epithelial cells. We observed that there is a functional coupling between CFTR and MRP2 that may be mediated by PDZ proteins. We also observed the existence of a macromolecular complex containing CFTR, MRP2, and PDZ proteins, which might form the basis for the regulatory cooperation between these two ABC transporters. Our results have important implications for cigarette smoke-associated lung diseases (such as smoke-related emphysema, chronic obstructive pulmonary disease, and lung cancer).

Effect of quercetin on nicotine-induced biochemical changes and DNA damage in rat peripheral blood lymphocytes

We elucidated the protective effect of quercetin, a polyphenolic flavonoid, on lipid peroxidation, endogenous antioxidant status and DNA damage during nicotine-induced toxicity in cultured rat peripheral blood lymphocytes as compared to N-acetylcysteine (NAC), a well-known antioxidant. Lymphocytes were exposed to nicotine (3 mM) with and without quercetin and NAC (1 mM) in RPMI-1640 medium for 1 h. In preliminary experiments to fix the effective dose of quercetin, different doses of quercetin (25, 50, 75, 100 and 200 microM) were administered to lymphocytes with nicotine, and lipid peroxidation markers (thiobarbituric acid reactive substances and hydroperoxides) were analysed. A 75 microM dose of quercetin was found to be effective as evidenced by decreased lipid peroxidation. To evaluate the protective potential of quercetin against genotoxic effects of nicotine we used comet and micronucleus assays, which are valid parameters to assess genetic damage. In addition, biochemical changes including lipid peroxidation and antioxidant status were assessed. There were significant increases in the levels of lipid peroxidation, comet parameters and micronuclei frequencies, followed by decrease in the endogenous antioxidant status, in nicotine-treated lymphocytes, which were brought back to near normal by quercetin or NAC treatment. The protective effect of quercetin against nicotine toxicity was comparable to that of NAC. These findings suggest that quercetin can be as effective as NAC in protecting rat peripheral lymphocytes against nicotine-induced cellular and DNA damage.

Does nicotine influence cytokine profile and subsequent cell cycling/apoptotic responses in inflammatory bowel disease?

BACKGROUND

Smoking differentially influences susceptibility to the inflammatory bowel diseases (IBDs) Crohn's disease (CD) and ulcerative colitis (UC). We investigated the effects of nicotine on cytokine, cell cycle, and apoptotic responses in peripheral blood mononuclear cells (PBMCs) from IBD patients and healthy controls (HCs).

METHODS

PBMCs from IBD patients and HC were stimulated with lipopolysaccharide (LPS; 1 microg/mL) or phytohemagglutinin (PHA, 5 or 0.5 microg/mL), +/- nicotine (1, 10, 100 microg/mL). Cytokines (IL1beta, IL2, IL10, IL12/IL23p40, TGFbeta, TNFalpha) were measured in supernatants at 24 hours. After 72 hours cells were analyzed by flow cytometry for cell cycle and apoptosis. Statistical modeling was used to identify interactions between cytokines and cell cycle / apoptosis and minimize confounding effects.

RESULTS

Stimulation by LPS and PHA (5 microg/mL) increased IL12/IL23p40 production from CD and UC versus HC (P < 0.05); PHA (0.5 microg/mL) increased IL1beta in UC and decreased TGFbeta from CD and UC (P < 0.01). In all groups, nicotine reduced LPS- and PHA (0.5 microg/mL)-stimulated production of IL1beta, IL10, TGFbeta, and TNFalpha (P < 0.001). Cell cycle analysis showed that PHA, but not LPS, induced proliferation and decreased G(0)/G(1) resting cells in CD and UC versus HC (P < 0.001). Nicotine decreased PHA-stimulated S-phase proliferation and increased G(0)/G(1) resting cells (P < 0.01). Modeling showed independent associations between IL12/IL23p40 and apoptosis (P = 0.01), IL1beta and resting cells (P = 0.006), TNFalpha and proliferating cells (P < 0.001). Disease activity and smoking habit had no effect.

CONCLUSIONS

Dysregulated cytokine profiles in UC and CD are associated with specific alterations in cell cycle responses; these effects may be modified by nicotine, and potentially by anticytokine therapies.

Carcinogenesis induced by foreign bodies

This review deals with the contemporary investigations of carcinogenesis induced by foreign bodies. The main attention is given to the interactions of macrophages with an implanted foreign body and their possible role in tumorigenesis.

Cigarette smoke exposure attenuates cytokine production by mouse alveolar macrophages

Alveolar macrophages (aMs) play a central role in respiratory host defense by sensing microbial antigens and initiating immune-inflammatory responses early in the course of an infection. The purpose of this study was to investigate the effect of cigarette smoke exposure on aMs after stimulation of innate pattern recognition receptors (PRRs) in a murine model. To accomplish this, C57BL/6 mice were exposed for 8 weeks using two models of cigarette smoke exposure, nose-only or whole-body exposure, and aMs isolated from the bronchoalveolar lavage. After stimulation of aMs with pI:C, a mimic of viral replication, and bacterial cell-wall constituent LPS, aMs from cigarette smoke-exposed mice produced significantly attenuated levels of the inflammatory cytokines TNF-alpha and IL-6, and the chemokine RANTES. This attenuation was specific to the aM compartment, and not related to changes in aM viability or expression of Toll-like receptor (TLR)3 or TLR4 between groups. Furthermore, aMs from smoke-exposed mice had decreased cytokine RNA as compared with aMs from sham-exposed mice. Mechanistically, this was associated with decreased nuclear translocation of the proinflammatory transcription factor NF-kappaB, and increased activator protein-1 nuclear translocation, in aMs from smoke-exposed mice. Attenuated cytokine production was reversible after smoking cessation. Cigarette smoke exposure also attenuated TNF-alpha production after stimulation with nucleotide-oligomerization domain-like receptor agonists, showing that the effect applies more broadly to other PRR pathways. Our data demonstrate that cigarette smoke exposure attenuates aM responses after innate stimulation, including pathways typically associated with bacterial and viral infections.

Protective effect of ferulic acid on nicotine-induced DNA damage and cellular changes in cultured rat peripheral blood lymphocytes: A comparison with N-acetylcysteine

Nicotine is the major pharmacologically active substance in cigarette smoke and plays an important etiological role in the development of lung cancer. Incidence of cancer may be related to oxidative damage to host genome by nicotine. These oxidative actions may be modified by the phytochemicals present in food. The present study describes the protective effect of ferulic acid (FA), a naturally occurring nutritional compound on nicotine-induced DNA damage and cellular changes in cultured rat peripheral blood lymphocytes in comparison with N-acetylcysteine (NAC), a well-known antioxidant. One-hour exposure of lymphocytes to nicotine at the doses of 0.125, 0.25, 0.5, 1, 2, 3 and 4 mM induced a statistically significant dose-dependent increase in the levels of thiobarbituric acid reactive substances (TBARS), a lipid peroxidative marker and decrease in the levels of reduced glutathione (GSH), an important endogenous antioxidant. The lowest concentration eliciting significant damage was 1 mM nicotine and maximum damage was observed with 3 mM concentration. Hence, the test concentration was fixed at 3 mM nicotine. We have used 5 different doses of FA (10, 50, 100, 150 and 300 microM) and NAC (0.25, 0.5, 1, 2 and 4 mM) to test their protective effects. In all the groups, FA and NAC showed a dose-dependent inhibitory effect. Maximum protection was observed at the dose of 150 microM FA and 1mM NAC. So, 150 microM FA and 1mM NAC were used for further studies. There was a significant increase in the levels of lipid peroxidative index (TBARS and hydroperoxides (HP)), severity of DNA damage (evaluated by comet assay) in nicotine-treated group, which were significantly decreased in FA and NAC-treated groups. Nicotine treatment significantly decreased the endogenous antioxidant status viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), GSH, vitamin A, E and C. Co-administration of FA and NAC to nicotine-treated lymphocytes showed a significant increase in the antioxidant status. The protective effect of FA was merely equal to that of NAC effect. FA and NAC treatment alone did not produce any toxicity to the normal lymphocytes at their effective doses. On the whole, there is overwhelming evidence that FA has the ability to modulate DNA damage and a variety of cellular changes that occur during nicotine-induced toxicity in rat peripheral blood lymphocytes.

Alveolar macrophage cytotoxic activity is inhibited by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a carcinogenic component of cigarette smoke

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a carcinogenic compound of cigarette smoke that generates electrophilic intermediates capable of damaging DNA. Recently, we have shown that NNK can modulate mediator production by alveolar macrophages (AM) and bronchial and alveolar epithelial cells, suggesting that cigarette smoke can alter lung immune response. Thus, we investigated the effect of NNK and cigarette smoke extract (CSE) on AM capacity to eliminate tumoral cells. Rat AM cell line, NR8383, was treated with NNK (500 microM) or CSE (3%) and stimulated with lipopolysaccharide (10 ng/ml). The release of cytotoxic mediators, tumor necrosis factor (TNF) and reactive oxygen species (ROS), was measured in cell-free supernatants using ELISA and superoxide anion production. TNF- and ROS-dependent cytotoxicity were studied using a (51)Chromium-release assay and WEHI-164 and P-815 cell lines. Treatment of AM with NNK and CSE for 18 h significantly inhibited AM TNF release. CSE exposure resulted in a significant increase of ROS production, whereas NNK did not. TNF-dependent cytotoxic activity of NR8383 and freshly isolated rat AM was significantly inhibited after treatment with NNK and CSE. Interestingly, although ROS production was stimulated by CSE and not affected by NNK, CSE inhibited AM ROS-dependent cytotoxicity. These results suggest that NNK may be one of the cigarette smoke components responsible for the reduction of pulmonary cytotoxicity. Thus, NNK may have a double pro-carcinogenic effect by contributing to DNA adduct formation and inhibiting AM cytotoxicity against tumoral cells.

Tissue homeostasis and cancer

Epithelial cells are known to release an important amount of cytokines capable to modulate immune system functions. On the other hand, immune system cells can release cytokines, which play an important role in the control of the growth of epithelial cells. In this paper, we stand the hypothesis that a mutual (reciprocal) growth regulation exists between epithelial cells and immune system. We propose a model describing plausible cytokine circuits that may regulate (inhibit) both epithelial growth and epithelial inflammation. In addition, we describe how dysfunction of these circuits could lead to tumoral growth, excessive inflammation or both. A failure in the regulation of epithelial growth by the immune system could give rise to a neoplasm, and a failure in the regulation of the immune system by the epithelium could give rise to inflammatory or autoimmune diseases. This model may satisfactorily explain the link between inflammation and cancer.

Ellagic acid, a natural polyphenol protects rat peripheral blood lymphocytes against nicotine-induced cellular and DNA damage in vitro: With the comparison of N-acetylcysteine

The present work is aimed at evaluating the protective effect of ellagic acid (EA), a natural polyphenolic compound that is widely distributed in fruits and nuts against nicotine-induced toxicity in rat peripheral blood lymphocytes. The effect of EA against nicotine toxicity was compared with N-acetylcysteine (NAC), a well-known antioxidant. Lymphocytes were exposed to nicotine at the doses of 0.125, 0.25, 0.5, 1, 2, 3 and 4 mM for 1h in culture media. Thiobarbituric acid reactive substances (TBARS), a lipid peroxidative marker and reduced glutathione (GSH), as indicative of endogenous antioxidant status were analyzed to fix the optimum dose. The lowest concentration eliciting significant damage was 1 mM nicotine and maximum damage was observed with 3 mM concentration, as evidenced by increased levels of TBARS and decreased levels of GSH. Hence, the test concentration was fixed at 3 mM nicotine. To establish most effective protective support we used five different concentrations of EA (10, 50, 100, 150 and 300 microM) against 3 mM nicotine. A dose-dependent inhibitory effect was observed with all doses of EA. Maximum protection was observed at the dose of 100 microM EA. So, 100 microM dose was used for further studies. We have tested five different concentrations of NAC-0.25, 0.5, 1, 2 and 4 mM to elucidate the optimum protective dose against nicotine toxicity. One millimolar NAC showed a significant protection against nicotine toxicity. Protective effect of EA against nicotine toxicity was elucidated by analyzing the lipid peroxidative index, viz., TBARS, hydroperoxides (HP) and endogenous antioxidant status, viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), Vitamins A, E and C. DNA damage and repair were assessed by using alkaline single-cell microgel electrophoresis (Comet assay) and micronucleus assay. There was a significant increase in the levels of lipid peroxidative index, severity in DNA damage and micronuclei number in nicotine-treated group, which was positively modulated by EA treatment. Antioxidant status was significantly depleted in nicotine-treated group, which was effectively restored by EA treatment. The protection of EA against nicotine toxicity was equally effective to that of NAC. EA and NAC treatment alone did not produce any damage to the normal lymphocytes at their effective doses. These findings suggest the potential use and benefit of EA as a modifier of nicotine-induced genotoxicity.

Increased oxidative stress in infants exposed to passive smoking

The purpose of this study was to assess the effect of passive cigarette smoking on the oxidative and anti-oxidative status of plasma in infants. Eighty-four infants aged 6-28 weeks were divided into two groups: the study group included infants who had been exposed to passive smoking via at least five cigarettes per day for at least the past 6 weeks at home, while the control group included infants who had never been exposed to passive smoking. The antioxidative status of plasma was assessed by the measurement of individual antioxidant components: vitamin C, albumin, bilirubin, uric acid, thiol contents and total antioxidant capacity (TAC 1 and TAC 2). Oxidative status was assessed by the determination of total peroxide levels and the oxidative stress index (OSI 1 and OSI 2). Plasma vitamin C, thiol concentration and TAC 1 and TAC 2 levels were significantly lower, whereas plasma total peroxide levels and OSI 1 and OSI 2 were significantly higher, in passive smoking infants than in the controls (P<0.01). We conclude that passive smoking has a negative impact on numerous parts of the antioxidant defence system in infants, and exposes them to potent oxidative stress.

Kinetic analysis of cytokine response to cigarette smoke condensate by human endothelial and monocytic cells

Atherosclerosis is generally considered an inflammatory disease characterized by the accumulation of lipid in large and medium elastic arteries. Individuals who smoke are at increased risk for developing atherosclerosis and the clinical events associated with this disease. Underlying the mechanisms involved in atherosclerotic lesion development exists a complex pattern of signaling, involving molecules (cytokines and chemokines) that mediate the progression of arterial lesions. The unique nature of exposure to tobacco-related toxicants during the process of smoking prompted our investigation of the time-dependent responses of two critical cell types to cigarette smoke condensate exposure. In this study, we examined the kinetic responses, using suspension array technology and RT-PCR of 17 cytokines (IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17 GM-CSF, G-CSF, INF-gamma, TNF-alpha, MCP-1 and MIP-1beta) in human aortic endothelial cells (HAECs) and THP-1 monocyte macrophages following exposure to cigarette smoke condensate (CSC) for 24h. In HAECs, IL-8 and IL-4 were rapidly stimulated by CSC exposure while, surprisingly, MCP-1 expression was downregulated. In THP-1 macrophages, IL-6, MIP-1beta, MCP-1 and IL-1beta protein expression were suppressed upon CSC exposure. All other measurable cytokines in THP-1 cells exposed to CSC had levels of protein and mRNA similar to controls. Depending on cell type, CSC uniquely influences the expression of cytokines. The complex interplay of these signaling molecules within the framework of atherosclerosis points to the ability of cigarette smoke components to alter such signaling following acute exposure, and by this mechanism may alter the course of both atherogenesis initiation and progression.

Palatine tonsils in smoker and non-smoker patients: a pilot clinicopathological and ultrastructural study

BACKGROUND

Tobacco smoke is a well-known source of toxic, mutagenic and carcinogenic agents. The aim of the present preliminary study was to investigate the effects of cigarette smoking on lymphoid and non-lymphoid tonsillar tissue.

METHODS

The study group consisted of 12 smoker and 10 non-smoker patients complaining recurrent tonsillitis. Clinical data, histological findings and scanning electron microscopic analyses were considered. To the best of our knowledge, such an approach has not been previously adopted in a similar experimental model.

RESULTS

Smoker patients showed a longer history of recurrent tonsillitis, difficulties in clinical management and evident morphostructural changes than non-smokers.

CONCLUSIONS

These preliminary results suggest a possible interference of cigarette smoking with the therapy response as well as a possible role of tobacco smoke in impairment of inflammatory response. Results are critically analysed and discussed. Literature data on this subject are reviewed.

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone, a component of tobacco smoke, modulates mediator release from human bronchial and alveolar epithelial cells

Respiratory epithelial cells are known to contribute to immune responses through the release of mediators. The aim of this study was to characterize the immunomodulatory effects of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a tobacco carcinogen, on respiratory epithelial cells and to compare two metabolic pathways, alpha-methylhydroxylation and alpha-methylenehydroxylation, involved in these effects using selective precursors, 4-(acetoxy-methylnitrosamino)-1-(3-pyridil)-1-butanone (NNKOAc) and N-nitroso (acetoxymethyl) methylamine (NDMAOAc), respectively. Human bronchial and alveolar epithelial cell lines, BEAS-2B and A549, respectively, were treated with NNK, NNKOAc and NDMAOAc for 24 h with and without tumour necrosis factor (TNF) and mediators released in cell-free supernatants were measured by enzyme-linked immunosorbent assay (ELISA). NNK significantly inhibited interleukin (IL)-8, IL-6 and monocyte chemoattractant protein-1 (MCP-1) production in both cell types. Similar results were observed with primary bronchial and alveolar epithelial cells. Although NNK increased prostaglandin E(2) (PGE(2)) production by A549 cells, its immunomodulatory effects were not mediated by PGE(2) according to the results with cyclo-oxygenase inhibitors. NNKOAc mimicked NNK effects, whereas NDMAOAc significantly inhibited IL-8 production in BEAS-2B cells and MCP-1 in both cell types. These results demonstrate that NNK and its reactive metabolites have immunosuppressive effects on respiratory epithelial cells, which could contribute to the increased respiratory infections observed in smokers and the development and/or the progression of lung cancer.

Hypersensitivity pneumonitis: a multifaceted deceiving disorder

Hypersensitivity pneumonitis (HP) represents a group of immunologically mediated lung disorders provoked by recurrent exposure to various environmental agents. HP is multifaceted and may mimic almost any interstitial lung disease, some infectious diseases,and even bronchiolar disorders. In the absence of a diagnostic gold standard,diagnosis of HP requires a combination of clinical, environmental, radiologic, physiologic,and pathologic findings that represent a diagnostic challenge for clinicians and-in the chronic form-even for experienced pathologists. Therapeutic approach includes avoiding further exposure and, depending on the clinical form, the administration of a course of prednisone. New anti-inflammatory, immunoregulatory, and antifibrotic drugs are urgently needed for this and other interstitial lung diseases.

An 18-month follow-up study on the influence of smoking on blood antioxidant status of teenage girls in comparison with adult male smokers in Korea

OBJECTIVES

The influence of cigarette smoking on blood antioxidant status in teenage girls with a history of short-term smoking was followed over 18 mo.

METHODS

Data obtained from female senior high school students (ages 14 to 18 y) in Korea were compared with data obtained from adult male smokers (ages 36 to 51 y) with a long history of smoking and living in the same geographic areas as the teenage subjects. A smoker was a person who had smoked at least three cigarettes a day for at least 1 y for teenagers (n = 35) or at least 10 cigarettes a day for at least 13 y for adults (n = 20). Serum, urine, and anthropometric data were obtained from teenagers every 6 mo over an 18-mo period. Samples were collected once from adults. Data were analyzed by Student's t test and Fisher's protected least significant difference test for comparing smokers and non-smokers and for analyzing period effects in each group.

RESULTS

Serum nicotine and cotinine concentrations were higher in smokers than in non-smokers. Blood pressures were higher in teenage (at 0 and 12 mo) and adult smokers than in non-smokers. Extracellular superoxide dismutase activities and concentrations of serum vitamin C and folate were lower in smokers in the teenage (at 0, 12, or 18 mo) and adult groups. Serum ceruloplasmin activities and thiobarbituric acid-reactive substance production were not influenced by smoking. In adults, serum copper concentrations were higher in smokers than in non-smokers. This parameter for teenagers did not change consistently throughout the study.

CONCLUSIONS

Similar to adults, cigarette smoking by teenagers has a negative effect on oxidant defense systems.