Modulation of Alveolar Macrophage Activity by Eugenol Attenuates Cigarette-Smoke-Induced Acute Lung Injury in Mice.

This study investigates the role of eugenol (EUG) on CS-induced acute lung injury (ALI) and how this compound is able to modulate macrophage activity. C57BL/6 mice were exposed to 12 cigarettes/day/5days and treated 15 min/day/5days with EUG. Rat alveolar macrophages (RAMs) were exposed to CSE (5%) and treated with EUG. In vivo, EUG reduced morphological changes inflammatory cells, oxidative stress markers, while, in vitro, it induced balance in the oxidative stress and reduced the pro-inflammatory cytokine release while increasing the anti-inflammatory one. These results suggest that eugenol reduced CS-induced ALI and acted as a modulator of macrophage activity.

Spatial metabolomics reveals glycogen as an actionable target for pulmonary fibrosis.

Matrix assisted laser desorption/ionization imaging has greatly improved our understanding of spatial biology, however a robust bioinformatic pipeline for data analysis is lacking. Here, we demonstrate the application of high-dimensionality reduction/spatial clustering and histopathological annotation of matrix assisted laser desorption/ionization imaging datasets to assess tissue metabolic heterogeneity in human lung diseases. Using metabolic features identified from this pipeline, we hypothesize that metabolic channeling between glycogen and N-linked glycans is a critical metabolic process favoring pulmonary fibrosis progression. To test our hypothesis, we induced pulmonary fibrosis in two different mouse models with lysosomal glycogen utilization deficiency. Both mouse models displayed blunted N-linked glycan levels and nearly 90% reduction in endpoint fibrosis when compared to WT animals. Collectively, we provide conclusive evidence that lysosomal utilization of glycogen is required for pulmonary fibrosis progression. In summary, our study provides a roadmap to leverage spatial metabolomics to understand foundational biology in pulmonary diseases.

Oxidative Stress and Inflammation in Acute and Chronic Lung Injuries.

Acute and chronic lung injuries are among the leading causes of mortality worldwide. Lung injury can affect several components of the respiratory system, including the airways, parenchyma, and pulmonary vasculature. Although acute and chronic lung injuries represent an enormous economic and clinical burden, currently available therapies primarily focus on alleviating disease symptoms rather than reversing and/or preventing lung pathology. Moreover, some supportive interventions, such as oxygen and mechanical ventilation, can lead to (further) deterioration of lung function and even the development of permanent injuries. Lastly, sepsis, which can originate extrapulmonary or in the respiratory system itself, contributes to many cases of lung-associated deaths. Considering these challenges, we aim to summarize molecular and cellular mechanisms, with a particular focus on airway inflammation and oxidative stress that lead to the characteristic pathophysiology of acute and chronic lung injuries. In addition, we will highlight the limitations of current therapeutic strategies and explore new antioxidant-based drug options that could potentially be effective in managing acute and chronic lung injuries.

Treatment with Bixin-Loaded Polymeric Nanoparticles Prevents Cigarette Smoke-Induced Acute Lung Inflammation and Oxidative Stress in Mice.

The use of annatto pigments has been evaluated as a therapeutic strategy in animal models of several health disorders. Beneficial effects were generally attributed to the inhibition of oxidative stress. Bixin is the main pigment present in annatto seeds and has emerged as an important scavenger of reactive oxygen (ROS) and nitrogen species (RNS). However, this carotenoid is highly hydrophobic, affecting its therapeutic applicability. Therefore, bixin represents an attractive target for nanotechnology to improve its pharmacokinetic parameters. In this study, we prepared bixin nanoparticles (npBX) and evaluated if they could prevent pulmonary inflammation and oxidative stress induced by cigarette smoke (CS). C57BL/6 mice were exposed to CS and treated daily (by gavage) with different concentrations of npBX (6, 12 and 18%) or blank nanoparticles (npBL, 18%). The negative control group was sham smoked and received 18% npBL. On day 6, the animals were euthanized, and bronchoalveolar lavage fluid (BALF), as well as lungs, were collected for analysis. CS exposure led to an increase in ROS and nitrite production, which was absent in animals treated with npBX. In addition, npBX treatment significantly reduced leukocyte numbers and TNF-α levels in the BALF of CS-exposed mice, and it strongly inhibited CS-induced increases in MDA and PNK in lung homogenates. Interestingly, npBX protective effects against oxidative stress seemed not to act via Nrf2 activation in the CS + npBX 18% group. In conclusion, npBX prevented oxidative stress and acute lung inflammation in a murine model of CS-induced acute lung inflammation.

Beneficial effects of Ilex paraguariensis in the prevention of obesity-associated metabolic disorders in mice.

Obesity is a chronic condition involving inflammation and oxidative stress that commonly predisposes affected individuals to develop metabolic disorders. We hypothesize that Ilex paraguariensis (IP) can modulate oxidative stress and inflammation underpinning metabolic disorders caused by obesity. C57BL/6 mice were fed a high-fat diet (HFD group) for 12 weeks. Concomitantly, some mice were treated with roasted IP (15 mg/ml - HFD + IP) or dimethyl fumarate (DMF) as a positive control (2 mg/ml - HFD + DMF). The control group received standard chow and water ad libitum. Histological analyses of fat tissue and liver, and quantification of mediators related to oxidative stress (Kelch-like ECH-associated protein 1/NF-E2-related factor 2, NADP(H) quinone oxidoreductase-1 [NQO1], heme oxygenase 1 [HO1], and superoxide dismutase) as well as metabolic profile blood biomarkers (glucose, leptin, resistin, high-density lipoproteins [HDLs], and triglycerides) were performed. Metabolic disorders were prevented in mice treated with IP, as evidenced by the observation that glucose, HDL, and resistin levels were similar to those assessed in the control group. Morphological analyses showed that both IP and DMF treatments prevented hepatic steatosis and adipocyte hypertrophy in visceral adipose tissue. Finally, although the antioxidant response stimulated by IP was quite limited, significant effects were found on NQO1 and HO1 expression. In conclusion, IP has promising preventative effects on the development of metabolic disorders caused by obesity.

Diallyl disulfide prevents cigarette smoke-induced emphysema in mice.

INTRODUCTION: Cigarette smoke (CS) is the main risk factor for the development of chronic obstructive pulmonary disease (COPD) and pulmonary emphysema. The use of antioxidants has emerged as a potential therapeutic strategy to treat airway inflammation and lung diseases. In the current study, we investigated the potential therapeutic impact of diallyl disulfide (Dads) treatment in a murine model of CS-induced emphysema. METHODS: C57BL/6 mice were exposed to CS for 60 consecutive days and treated with vehicle or Dads (30, 60 or 90 mg/kg) by oral gavage for the last 30 days, three times/week. The control group was sham-smoked and received vehicle treatment. All mice were euthanized 24 h after day 60; bronchoalveolar lavage (BAL) was performed and lungs were processed for further experimentation. Histological (HE stained sections, assessment of mean linear intercept (Lm)), biochemical (nitrite, superoxide dismutase (SOD), glutathione transferase (GST), and malondialdehyde (MDA) equivalents), and molecular biology (metalloproteinase (MMP) 12, SOD2, carbonyl reductase 1 (CBR1), nitrotyrosine (PNK), 4-hydroxynonenal (4-HNE), and CYP2E1) analyses were performed. RESULTS: Treatment with Dads dose-dependently reduced CS-induced leukocyte infiltration into the airways (based on BAL fluid counts) and improved lung histology (indicated by a reduction of Lm). Furthermore, CS exposure dramatically reduced the activity of the antioxidant enzymes SOD and GST in lung tissue and increased nitrite and MDA levels in BAL; these effects were all effectively counteracted by Dads treatment. Western blot analysis further confirmed the antioxidant potential of Dads, showing that treatment prevented the CS-induced decrease in SOD2 expression and increase in lung damage markers, such as CBR1, PNK, and 4-HNE. Furthermore, increased MMP12 (an important hallmark of CS-induced emphysema) and CYP2E1 lung protein levels were significantly reduced in mice receiving Dads treatment. CONCLUSION: Our findings demonstrate that treatment with Dads is effective in preventing multiple pathological features of CS-induced emphysema in an in vivo mouse model. In addition, we have identified several proteins/enzymes, including 4-HNE, CBR1, and CYP2E1, that are modifiable by Dads and could represent specific therapeutic targets for the treatment of COPD and emphysema.

Dimethyl Fumarate Attenuates Lung Inflammation and Oxidative Stress Induced by Chronic Exposure to Diesel Exhaust Particles in Mice.

Air pollution is mainly caused by burning of fossil fuels, such as diesel, and is associated with increased morbidity and mortality due to adverse health effects induced by inflammation and oxidative stress. Dimethyl fumarate (DMF) is a fumaric acid ester and acts as an antioxidant and anti-inflammatory agent. We investigated the potential therapeutic effects of DMF on pulmonary damage caused by chronic exposure to diesel exhaust particles (DEPs). Mice were challenged with DEPs (30 µg per mice) by intranasal instillation for 60 consecutive days. After the first 30 days, the animals were treated daily with 30 mg/kg of DMF by gavage for the remainder of the experimental period. We demonstrated a reduction in total inflammatory cell number in the bronchoalveolar lavage (BAL) of mice subjected to DEP + DMF as compared to those exposed to DEPs alone. Importantly, DMF treatment was able to reduce lung injury caused by DEP exposure. Intracellular total reactive oxygen species (ROS), peroxynitrite (OONO), and nitric oxide (NO) levels were significantly lower in the DEP + DMF than in the DEP group. In addition, DMF treatment reduced the protein expression of kelch-like ECH-associated protein 1 (Keap-1) in lung lysates from DEP-exposed mice, whereas total nuclear factor κB (NF-κB) p65 expression was decreased below baseline in the DEP + DMF group compared to both the control and DEP groups. Lastly, DMF markedly reduced DEP-induced expression of nitrotyrosine, glutathione peroxidase-1/2 (Gpx-1/2), and catalase in mouse lungs. In summary, DMF treatment effectively reduced lung injury, inflammation, and oxidative and nitrosative stress induced by chronic DEP exposure. Consequently, it may lead to new therapies to diminish lung injury caused by air pollutants.

Function of cAMP scaffolds in obstructive lung disease: Focus on epithelial-to-mesenchymal transition and oxidative stress.

Over the past decades, research has defined cAMP as one of the central cellular nodes in sensing and integrating multiple pathways and as a pivotal role player in lung pathophysiology. Obstructive lung disorders, such as chronic obstructive pulmonary disease (COPD), are characterized by a persistent and progressive airflow limitation and by oxidative stress from endogenous and exogenous insults. The extent of airflow obstruction depends on the relative deposition of different constituents of the extracellular matrix, a process related to epithelial-to-mesenchymal transition, and which subsequently results in airway fibrosis. Oxidative stress from endogenous and also from exogenous sources causes a profound worsening of COPD. Here we describe how cAMP scaffolds and their different signalosomes in different subcellular compartments may contribute to COPD. Future research will require translational studies to alleviate disease symptoms by pharmacologically targeting the cAMP scaffolds. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.

Eucalyptol promotes lung repair in mice following cigarette smoke-induced emphysema.

BACKGROUND: Eucalyptol is a monoterpenoid oil present in many plants, principally the Eucalyptus species, and has been reported to have anti-inflammatory and antioxidative effects. HYPOTHESIS/PURPOSE: Since the potential effect of eucalyptol on mouse lung repair has not yet been studied, and considering that chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide, the aim of this study was to investigate eucalyptol treatment in emphysematous mice. STUDY DESIGN: Male mice (C57BL/6) were divided into the following groups: control (sham-exposed), cigarette smoke (CS) (mice exposed to 12 cigarettes a day for 60 days), CS + 1 mg/ml (CS mice treated with 1 mg/ml eucalyptol for 60 days), and CS + 10 mg/ml (CS mice treated with 10 mg/ml eucalyptol for 60 days). Mice in the CS and control groups received vehicle for 60 days. Eucalyptol (or the vehicle) was administered via inhalation (15 min/daily). Mice were sacrificed 24 h after the completion of the 120-day experimental procedure. METHODS: Histology and additional lung morphometric analyses, including analysis of mean linear intercept (Lm) and volume density of alveolar septa (Vv[alveolar septa]) were performed. Biochemical analyses were also performed using colorimetric assays for myeloperoxidase (MPO), malondialdehyde (MDA), and superoxide dismutase (SOD) activity, in addition to using ELISA kits for the determination of inflammatory marker levels (tumor necrosis factor alpha [TNF-α], interleukin-1 beta [IL-1ß], interleukin 6 [IL-6], keratinocyte chemoattractant [KC], and tumor growth factor beta 1 [TGF-ß1]). Finally, we investigated protein levels by western blotting (nuclear factor (erythroid-derived 2)-like 2 [Nrf2], nuclear factor kappa B [NF-κB], matrix metalloproteinase 12 [MMP-12], tissue inhibitor of matrix metalloproteinase 1 [TIMP-1], neutrophil elastase [NE], and elastin). RESULTS: Eucalyptol promoted lung repair at the higher dose (10 mg/ml), with de novo formation of alveoli, when compared to the CS group. This result was confirmed with Lm and Vv[alveolar septa] morphometric analyses. Moreover, collagen deposit around the peribronchiolar area was reduced with eucalyptol treatment when compared to the CS group. Eucalyptol also reduced all inflammatory (MPO, TNF-α, IL-1ß, IL-6, KC, and TGF-ß1) and redox marker levels (MDA) when compared to the CS group (at least p < 0.05). In general, 10 mg/ml eucalyptol was more effective than 1 mg/ml and, at both doses, we observed an upregulation of SOD activity when compared to the CS group (p < 0.001). Eucalyptol upregulated elastin and TIMP-1 levels, and reduced neutrophil elastase (NE) levels, when compared to the CS group. CONCLUSION: In summary, eucalyptol promoted lung repair in emphysematous mice and represents a potential therapeutic phytomedicine in the treatment of COPD.

Mate tea reduces high fat diet-induced liver and metabolic disorders in mice.

High-fat diet (HFD)-induced obesity is a worldwide health problem and can cause lipid accumulation in the liver. We evaluated the hepatoprotective effect of mate tea treatment in mice submitted to an HFD. C57BL/6 mice were fed an HFD for 13 weeks with and without mate tea. A separate group of mice was treated with fenofibrate as a positive control (a regular drug for lipid disorders). Histological analyses, glucose tolerance tests (GTT), and quantification of mediators related to lipid peroxidation, oxidative stress and blood biomarkers for lipid profile were performed. The weight of animals and major organs related to hepatic steatosis was determined, and proinflammatory cytokines and the participation of the Nrf2 pathway and adiponectin were evaluated. Mate tea prevented the accumulation of lipid droplets in hepatocytes as well as weight gain in animals submitted to the HFD. Mate tea treatment also prevented increases in the liver weight, heart weight and amount of visceral and subcutaneous white adipose tissue. Mate tea was able to prevent the deregulation of glucose uptake, as evaluated by GTT, and improved the indicators of oxidative stress, such as nitrite levels, catalase activity, and oxidative damage, as evaluated by protein carbonylation and the MDA levels. Mate tea had an anti-inflammatory effect, preventing the increase of IL-1ß and KC and upregulating the expression of Nrf2. Mate tea prevented insulin increase and HDL cholesterol decrease but did not affect total cholesterol or triglycerides levels. Treatment also prevented adiponectin increase. Mate tea may be a good resource to reduce hepatic steatosis in the future since it has anti-diabetic, anti-inflammatory and antioxidant effects, which prevent the accumulation of fat in the liver.

Acute Exposure to Diesel-Biodiesel Particulate Matter Promotes Murine Lung Oxidative Stress by Nrf2/HO-1 and Inflammation Through the NF-kB/TNF-α Pathways.

Air pollution caused by fuel burning contributes to respiratory impairments that may lead to death. We aimed to investigate the effects of biodiesel (DB) burning in mouse lungs. DB particulate matter was collected from the exhaust pipes of a bus engine. Mice were treated with 250 µg or 1000 µg of DB particulate matter by intranasal instillation over 5 consecutive days. We demonstrated that DB particulate matter penetrated the lung in the 250-µg and 1000-µg groups. In addition, the DB particulate matter number in pulmonary parenchyma was 175-fold higher in the 250-µg group and 300-fold higher in the 1000-µg group compared to control mice. The instillation of DB particulate matter increased the macrophage number and protein levels of TNF-alpha in murine lungs. DB particulate matter enhanced ROS production in both exposed groups and the malondialdehyde levels compared to the control group. The protein expression levels of Nrf2, p-NF-kB, and HO-1 were higher in the 250-µg group and lower in the 1000-µg group than in control mice and the 250-µg group. In conclusion, DB particulate matter instillation promotes oxidative stress by activating the Nrf2/HO-1 and inflammation by p-NF-kB/TNF-alpha pathways.

Atorvastatin dose-dependently promotes mouse lung repair after emphysema induced by elastase.

Emphysema results in a proteinase - antiproteinase imbalance, inflammation and oxidative stress. Our objective was to investigate whether atorvastatin could repair mouse lungs after elastase-induced emphysema. Vehicle (50 µL) or porcine pancreatic elastase (PPE) was administered on day 1, 3, 5 and 7 at 0.6 U intranasally. Male mice were divided into a control group (sham), PPE 32d (sacrificed 24 h after 32 days), PPE 64d (sacrificed 24 h after 64 days), and atorvastatin 1, 5 and 20 mg treated from day 33 until day 64 and sacrificed 24 h later (A1 mg, A5 mg and A20 mg, respectively). Treatment with atorvastatin was performed via inhalation for 10 min once a day. We observed that emphysema at day 32 was similar to emphysema at day 64. The mean airspace chord length (Lm) indicated a recovery of pulmonary morphology in groups A5 mg and A20 mg, as well as recovery of collagen and elastic fibers in comparison to the PPE group. Bronchoalveolar lavage fluid (BALF) leukocytes were reduced in all atorvastatin-treated groups. However, tissue macrophages were reduced only in the A20 mg group compared with the PPE group, while tissue neutrophils were reduced in the A5 mg and A20 mg groups. The redox balance was restored mainly in the A20 mg group compared with the PPE group. Finally, atorvastatin at doses of 5 and 20 mg reduced nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and matrix metalloproteinase-12 (MMP-12) compared with the PPE group. In conclusion, atorvastatin was able to induce lung tissue repair in emphysematous mice.

AT-RVD1 repairs mouse lung after cigarette smoke-induced emphysema via downregulation of oxidative stress by NRF2/KEAP1 pathway.

Long-term exposure to cigarette smoke (CS) results in alveolar parenchyma destruction due to chronic inflammatory response and the imbalance between oxidants and antioxidants, and proteases and antiproteases. Emphysema is the main symptom of chronic obstructive pulmonary disease. Current treatment focuses on relieving respiratory symptoms, and inflammation resolution failure is an important pathophysiological element of the disease. Specialized pro-resolving mediators (SPMs) synthesized endogenously during resolution processes demonstrated beneficial effects in murine models of airway inflammation. Here, we aimed to test the SPM AT-RvD1 in a murine model of CS-induced emphysema. AT-RvD1 restored elastic fibers and lung morphology, with reduction in MMP-3, neutrophils, and myeloperoxidase activity and increases in macrophages and IL-10 levels. AT-RvD1 also decreased levels of oxidative stress markers and ROS via upregulation of the Nrf2/Keap1 pathway. Therefore, we suggest that AT-RvD1 causes pro-resolutive action in our murine model of CS-induced emphysema by upregulation of the Nrf2/Keap1 pathway.

PTGS2 polymorphism rs689466 favors breast cancer recurrence in obese patients.

Breast cancer is the leading cancer among women, and its increasing incidence is a challenge worldwide. Estrogen exposure is the main risk factor, but obesity among postmenopausal women has been shown to favor disease onset and progression. The link between obesity and mammary carcinogenesis involves elevated estrogen production and proinflammatory stimuli within the adipose tissue, with activation of the cyclooxygenase-2 pathway. Here, we evaluate the impact of the four most common cyclooxygenase-2 gene polymorphisms (rs689465, rs689466, rs20417 and rs20417), in combination with obesity, on the risk of breast cancer progression in a cohort of Brazilian breast cancer patients (N = 1038). Disease-free survival was evaluated using Kaplan-Meier curves, with multivariate Cox proportional hazards regression models for calculation of adjusted hazard ratios (HRadj). Obesity did not affect disease progression, whereas rs689466 variant genotypes increased the recurrence risk among obese patients (HRadj = 2.5; 95% CI = 1.4-4.3), either for luminal (HRadj = 2.2; 95% CI = 1.1-4.2) or HER2-like and triple-negative tumors (HRadj = 3.2; 95% CI = 1.2-8.5). Likewise, the haplotype *4, which contains variant rs689466, was associated with shorter disease-free survival among obese patients (HRadj = 3.3; 95% CI = 1.8-6.0), either in luminal (HRadj = 3.5; 95% CI = 1.6-7.3) or HER2-like and triple-negative (HRadj = 3.1; 95% CI = 1.1-8.9) tumors. Such deleterious impact of variant rs689466 on disease-free survival of obese breast cancer patients was restricted to postmenopausal women. In conclusion, cyclooxygenase-2 genotyping may add to the prognostic evaluation of obese breast cancer patients.

Propolis reversed cigarette smoke-induced emphysema through macrophage alternative activation independent of Nrf2.

Chronic obstructive pulmonary disease (COPD) is an incurable and progressive disease. Emphysema is the principal manifestation of COPD, and the main cause of this condition is cigarette smoke (CS). Natural products have shown antioxidant and anti-inflammatory properties that can prevent acute lung inflammation and emphysema, but there are few reports in the literature regarding therapeutic approaches to emphysema. We hypothesized that supplementation with natural extracts would repair lung damage in emphysema caused by CS exposure. Mice were exposed to 60days of CS and then treated or not with three different natural extracts (mate tea, grape and propolis) orally for additional 60days. Histological analysis revealed significant improvements in lung histoarchitecture, with recovery of alveolar spaces in all groups treated with natural extracts. Propolis was also able to recovery alveolar septa and elastic fibers. Propolis also increased MMP-2 and decreased MMP-12 expression, favoring the process of tissue repair. Additionally, propolis recruited leukocytes, including macrophages, without ROS release. These findings led us to investigate the profile of these macrophages, and we showed that propolis could promote macrophage alternative activation, thus increasing the number of arginase-positive cells and IL-10 levels and favoring an anti-inflammatory microenvironment. We further investigated the participation of Nrf2 in lung repair, but no Nrf2 translocation to the nucleus was observed in lung cells. Proteins and enzymes related to Nrf2 were not altered, other than NQO1, which seemed to be activated by propolis in a Nrf2-independent manner. Finally, propolis downregulated IGF1 expression. In conclusion, propolis promoted lung repair in a mouse emphysema model via macrophage polarization from M1 to M2 in parallel to the downregulation of IGF1 expression in a Nrf2-independent manner.

Pharmacological modulation of reactive oxygen species (ROS) improves the airway hyperresponsiveness by shifting the Th1 response in allergic inflammation induced by ovalbumin.

Asthma is an allergic inflammation driven by the Th2 immune response with release of cytokines such as IL-4 and IL-13, which contribute to the airflow limitations and airway hyperresponsiveness (AHR). The involvement of oxidative stress in this process is well-established, but the specific role of the superoxide anion and nitric oxide in asthma are poorly understood. Thus, the aim of this study was to investigate the mechanisms underlying the superoxide anion/nitric oxide production and detoxification in a murine asthma model. BALB/c male mice were sensitised and challenged with ovalbumin (OVA). Pretreatments with either apocynin (14 mg/kg) or allopurinol (25 mg/kg) (superoxide anion synthesis inhibitors), aminoguanidine (50 mg/kg) (nitric oxide synthesis inhibitor) or diethyldithiocarbamate (100 mg/kg) (superoxide dismutase inhibitor) were performed 1 h before the challenge. Our data showed that apocynin and allopurinol ameliorated AHR and reduced eosinophil peroxidase, as well as IL-4 and IL-13 levels. Apocynin also abrogated leukocyte peribronchiolar infiltrate and increased IL-1ß secretion. Aminoguanidine preserved lung function and shifted the Th2 to the Th1 response with a reduction of IL-4 and IL-13 and increase in IL-1ß production. Diethyldithiocarbamate prevented neither allergen-induced AHR nor eosinophil peroxidase (EPO) generation. All treatments protected against oxidative damage observed by a reduction in TBARS levels. Taken together, these results suggest that AHR in an asthma model can be avoided by the down-regulation of superoxide anion and nitric oxide synthesis in a mechanism that is independent of a redox response. This down-regulation is also associated with a transition in the typical immunological Th2 response toward the Th1 profile.

Pulmonary Emphysema Cross-Linking with Pulmonary Fibrosis and Vice Versa: a Non-usual Experimental Intervention with Elastase and Bleomycin.

Elastase (PPE) is usually used for emphysema models, whereas bleomycin (BLM) is used for fibrosis models. The aim of this study was to investigate the effect of BLM in PPE-induced emphysema, as well as the effect of PPE in BLM-induced fibrosis. C57BL/6 mice were divided into five groups: control, PPE, BLM, PPE + BLM, and BLM + PPE. Mice received saline, PPE (3 U/mouse), or BLM (20 U/kg) by intranasal instillation. Mice from the BLM and BLM + PPE groups received BLM on day 0 and saline or PPE on day 21, respectively. Those in the PPE and PPE + BLM groups received PPE on day 0 and saline or BLM on day 21, respectively. Mice were euthanized on day 42. We performed histology, morphometry in lung sections and ELISA, zymography and western blotting in BAL samples or lung homogenates. In the lungs of PPE + BLM and BLM + PPE groups, we observed inflammation, oxidative stress and expression of MMP-2 and MMP-9. The alveolar enlargement was reduced in the PPE + BLM group, suggesting that the BLM could participate in the alveolar remodeling process. The significance of this result supports future therapeutic approaches targeting extracellular-matrix deposition in patients with emphysema as a way to repair the enlargement of alveoli and airspaces.

Inflammatory and Oxidative Stress Markers in Experimental Allergic Asthma.

Ovalbumin-induced allergic lung inflammation (ALI) is a condition believed to be mediated by cytokines, extracellular matrix remodeling, and redox imbalance. In this study, we evaluated pulmonary function together with inflammatory markers as interleukin-4 (IL-4), myeloperoxidase (MPO), eosinophil cells, and redox markers in the lungs of BALB/c mice after ovalbumin (OVA) sensitization and challenge. Our results showed an increase in bronchial hyperresponsiveness stimulated by methacholine (Mch), inflammatory cell influx, especially eosinophils together with an increase of high mobility group box 1 (HMGB1) and altered lipid peroxidation (LP) and antioxidant defenses in the OVA group compared to the control group (p ≤ 0.5). Thus, we demonstrated that OVA-induced ALI altered redox status concomitantly with impaired lung function, which was associated with HMGB1 expression and proteolytic remodeling. Taken together all results found here, we may suggest HMGB1 is an important therapeutic target for asthma, once orchestrates the redox signaling, inflammation, and remodeling that contribute to the disease development.

Atorvastatin and Simvastatin Promoted Mouse Lung Repair After Cigarette Smoke-Induced Emphysema.

Cigarette smoke (CS) induces pulmonary emphysema by inflammation, oxidative stress, and metalloproteinase (MMP) activation. Pharmacological research studies have not focused on tissue repair after the establishment of emphysema but have instead focused on inflammatory stimulation. The aim of our study was to analyze the effects of atorvastatin and simvastatin on mouse lung repair after emphysema caused by CS. Male mice (C57BL/6, n = 45) were divided into the following groups: control (sham-exposed), CSr (mice exposed to 12 cigarettes a day for 60 days and then treated for another 60 days with the vehicle), CSr+A (CSr mice treated with atorvastatin for 60 days), and CSr+S (CSr mice treated with simvastatin for 60 days). The treatment with atorvastatin and simvastatin was administered via inhalation (15 min with 1 mg/mL once a day). Mice were sacrificed 24 h after the completion of the 120-day experimental procedure. We performed biochemical, morphological, and physiological analyses. We observed decreased levels of leukocytes and cytokines in statin-treated mice, accompanied by a reduction in oxidative stress markers. We also observed a morphological improvement confirmed by a mean linear intercept counting in statin-treated mice. Finally, statins also ameliorated lung function. We conclude that inhaled atorvastatin and simvastatin improved lung repair after cigarette smoke-induced emphysema in mice.

Eucalyptol attenuates cigarette smoke-induced acute lung inflammation and oxidative stress in the mouse.

Short-term cigarette smoke (CS) exposure does not cause emphysema; however, some pathogenesis hallmarks are maintained, such as oxidative stress and inflammation. This study aimed to test the efficacy of eucalyptol against short-term CS exposure in mice. C57BL/6 mice were exposed to 12 cigarettes per day for 5 days (CS group). The control group was exposed to sham smoking. Three groups of mice exposed to CS were treated to different concentrations of eucalyptol (1, 3, 10 mg/mL) via inhalation (15 min/daily) for 5 days (CS + 1 mg, CS+3 mg and CS+10 mg groups). CS group and control one were sham treated by using vehicle. The anti-inflammatory and antioxidant effects of eucalyptol were assessed 24 h after the last CS exposure by determining cell counts, measuring cytokine production and performing western blotting, biochemical and histological analyses. Eucalyptol at 3 mg/mL and 10 mg/mL concentrations reduced total leukocyte numbers compared to the CS group (p < 0.001), while macrophage numbers were reduced at all concentrations (p < 0.001). Myeloperoxidase, used as neutrophil marker, was reduced at 3 mg/mL (p < 0.01) and 10 mg/mL (p < 0.05) concentrations. Eucalyptol reduced cytokine levels (IL-1ß, IL-6 and KC) at 3 mg/mL and 10 mg/mL concentrations (p < 0.01) compared to the CS group. The exception was TNF-α, with a reduction only at 10 mg/mL of eucalyptol compared to the CS group (p < 0.001). Additionally, eucalyptol decreased the NF-kappa B p65 subunit at 3 mg/mL and 10 mg/mL compared to the CS group (p < 0.01). Regarding oxidative stress, eucalyptol reduced reactive oxygen species, superoxide dismutase, catalase and malondialdehyde, mainly at 3 mg/mL and 10 mg/mL concentrations compared to the CS group (at least p < 0.05), parallel to reduced glutathione levels at the same concentrations (p < 0.001). Furthermore, treatment with eucalyptol attenuated CS-induced histopathological alterations. Collectively, these results indicate that eucalyptol acts through a mechanism involving decreased oxidative stress, inflammation and the NF-kappa B p65 subunit against CS-induced acute lung inflammation. Thus, eucalyptol may be a potential agent in the treatment of pulmonary inflammation caused by CS in humans.