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.

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.

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.

The influence of 5-lipoxygenase on cigarette smoke-induced emphysema in mice.

BACKGROUND: Pulmonary emphysema is characterized by the loss of lung architecture. Our hypothesis is that the inhibition of 5-lipoxygenase (5-LO) production may be an important strategy to reduce inflammation, oxidative stress, and metalloproteinases in lung tissue resulting from cigarette smoke (CS)-induced emphysema. METHODS: 5-LO knockout (129S2-Alox5(tm1Fun)/J) and wild-type (WT) mice (129S2/SvPas) were exposed to CS for 60days. Mice exposed to ambient air were used as Controls. Oxidative, inflammatory, and proteolytic markers were analyzed. RESULTS: The alveolar diameter was decreased in CS 5-LO(-/-) mice when compared with the WT CS group. The CS exposure resulted in less pronounced pulmonary inflammation in the CS 5-LO(-/-) group. The CS 5-LO(-/-) group showed leukotriene B4 values comparable to those of the Control group. The expression of MMP-9 was decreased in the CS 5-LO(-/-) group when compared with the CS WT group. The expression of superoxide dismutase, catalase, and glutathione peroxidase were decreased in the CS 5-LO(-/-) group when compared with the Control group. The protein expression of nuclear factor (erythroid-derived 2)-like 2 was reduced in the CS 5-LO(-/-) group when compared to the CS WT group. CONCLUSION: In conclusion, we show for the first time that 5-LO deficiency protects 129S2 mice against emphysema caused by CS. We suggest that the main mechanism of pathogenesis in this model involves the imbalance between proteases and antiproteases, particularly the association between MMP-9 and TIMP-1. General significance This study demonstrates the influence of 5-LO mediated oxidative stress, inflammation, and proteolytic markers in CS exposed mice.

Critical role for CCR2 and HMGB1 in induction of experimental endotoxic shock.

Our aim was to investigate CCR2 and HMGB1 involvement in a murine model of endotoxic shock. We used C57BL/6 CCR2 knockout (KO) mice and wild-type (WT) littermates to establish an optimal dose of LPS. CCR2 KO mice survived more frequently than WT mice after 80, 40 and 20 mg/kg of LPS i.p. Inflammation and redox markers were high in WT mice than in CCR2 KO mice. HMGB1 expression was reduced in CCR2 KO mice in parallel to ERK 1/2 activation. Therefore, we used glycyrrhizic acid (50 mg/kg), an HMGB1 inhibitor in WT mice injected with LPS, and mortality was fully abolished. Thus, drugs targeting CCR2 and HMGB1 could represent future resources for sepsis treatment.

Antioxidant action of propolis on mouse lungs exposed to short-term cigarette smoke.

Propolis is a natural product with antioxidant properties. In this study, we tested the efficacy of propolis against acute lung inflammation (ALI) caused by cigarette smoke (CS). C57BL6 male mice were exposed to CS and treated with propolis (200mg/kg orally, CS+P) or only with propolis (P). A Control group treated with propolis was sham-smoked (Control+P). We collected the lungs for histological and biochemical analyses. We observed an increase in alveolar macrophages and neutrophils in the CS group compared with the Control+P. These counts reduced in the CS+P group compared to the CS group. The treatment with propolis normalized all biochemical parameters in the CS+P group compared with the CS group, including nitrite, myeloperoxidase level, antioxidant enzyme activities (superoxide dismutase, catalase and glutathione peroxidase), reduced glutathione/oxidized glutathione ratio and malondialdehyde. Additionally, TNF-α expression reduced in the CS+P group when compared with the CS group. These data imply a potential antioxidant and anti-inflammatory role for propolis with regard to ALI caused by CS in mice.

Effects of exercise on monocrotaline-induced changes in right heart function and pulmonary artery remodeling in rats.

Pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) is an experimental protocol of right heart failure. We analyzed the role of exercise training on the right ventricle structure and function, pulmonary artery remodeling, and GSK-3ß expression. Rats were divided among the following groups: sedentary control (SC), sedentary monocrotaline (SM), trained control (TC), and trained monocrotaline (TM). Rats underwent exercise training for a period of 5 weeks, with 3 weeks post-MCT injection. Rats in the SM and TM groups presented with an increase in right ventricle hypertrophy indexes and lung congestion. The right ventricular end diastolic pressure (RVEDP), right ventricular systolic pressure (RVSP), and its minimum and maximal pressure derivates were increased in the SM and TM groups. The right ventricle interstitial volume pulmonary artery thickness and p-GSK-3ß/GSK-3ß were increased in the MCT groups as compared with the control groups. The TM group had a reduction in interstitial volume, p-GSK-3ß/GSK-3ß ratio, pulmonary artery thickness, RVEDP, and an increase in intramyocardial vessels volume as compared with the SM group. The overall results have shown that the exercise protocol used promoted positive changes in right ventricle and pulmonary artery remodeling. These observations also suggest that structural remodeling may be influenced by signaling proteins, such as GSK-3ß.

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.

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.

Redox imbalance and pulmonary function in bleomycin-induced fibrosis in C57BL/6, DBA/2, and BALB/c mice.

The development of bleomycin-induced pulmonary fibrosis (BLEO-PF) has been associated with differences in genetic background and oxidative stress status. The authors' aim was to investigate the crosstalk between the redox profile, lung histology, and respiratory function in BLEO-PF in C57BL/6, DBA/2, and BALB/c mice. BLEO-PF was induced with a single intratracheal dose of bleomycin (0.1 U/mouse). Twenty-one days after bleomycin administration, the mortality rate was over 50% in C57BL/6 and 20% in DBA/2 mice, and BLEO-PF was not observed in BALB/c. There was an increase in lung static elastance (p < .001), viscoelastic/inhomogeneous pressure (p < .05), total pressure drop after flow interruption (p < .01), and ΔE (p < .05) in C57BL/6 mice. The septa volume increased in C57BL/6 (p < .05) and DBA/2 (p < .001). The levels of IFN-γ were reduced in C57BL/6 mice (p < .01). OH-proline levels were increased in C57BL/6 and DBA/2 mice (p < .05). SOD activity and expression were reduced in C57BL/6 and DBA/2 mice (p < .001 and p < .001, respectively), whereas catalase was reduced in all strains 21 days following bleomycin administration compared with the saline groups (C57BL/6: p < .05; DBA/2: p < .01; BALB/c: p < .01). GPx activity and GPx1/2 expression decreased in C57BL/6 (p < .001). The authors conclude that BLEO-PF resistance may also be related to the activity and expression of SOD in BALB/c mice.

Low-level infrared laser effect on plasmid DNA.

Low-level laser therapy is used in the treatment of many diseases based on its biostimulative effect. However, the photobiological basis for its mechanism of action and adverse effects are not well understood. The aim of this study, using experimental models, was to evaluate the effects of laser on bacterial plasmids in alkaline agarose gel electrophoresis and Escherichia coli cultures. The electrophoretic profile of bacterial plasmids in alkaline agarose gels were used for studying lesions in DNA exposed to infrared laser. Transformation efficiency and survival of Escherichia coli AB1157 (wild-type), BH20 (fpg/mutM(-)), BW9091 (xth(-)), and DH5αF'Iq (recA(-)) cells harboring pBSK plasmids were used as experimental models to assess the effect of laser on plasmid DNA outside and inside of cells. Data indicate low-level laser: (1) altered the electrophoretic profile of plasmids in alkaline gels at 2,500-Hz pulsed-emission mode but did not alter at continuous wave, 2.5- and 250-Hz pulsed-emission mode; (2) altered the transformation efficiency of plasmids in wild-type and fpg/mutM(-) E. coli cells; (3) altered the survival fpg/mutM(-), xthA(-) and recA(-) E. coli cultures harboring pBSK plasmids. Low-level infrared laser with therapeutic fluencies at high frequency in pulsed-emission modes have effects on bacterial plasmids. Infrared laser action can differently affect the survival of plasmids in E. coli cells proficient and deficient in DNA repair mechanisms, therefore, laser therapy protocol should take into account fluencies, frequencies and wavelength of laser, as well as tissue conditions and genetic characteristics of cells before beginning treatment.

Low-intensity infrared laser increases plasma proteins and induces oxidative stress in vitro.

Low-intensity laser therapy is based on the excitation of endogenous chromophores in biotissues and free-radical generation could be involved in its biological effects. In this work, the effects of the low-intensity infrared laser on plasma protein content and oxidative stress in blood from Wistar rats were studied. Blood samples from Wistar rats were exposed to low-intensity infrared laser in continuous wave and pulsed-emission modes at different fluencies. Plasma protein content and two oxidative stress markers (thiobarbituric acid-reactive species formation and myeloperoxidase activity) were carried out to assess the effects of laser irradiation on blood samples. Low-intensity infrared laser exposure increases plasma protein content, induces lipid peroxidation, and increases myeloperoxidase activity in a dose- and frequency-dependent way in blood samples. The low-intensity infrared laser increases plasma protein content and oxidative stress in blood samples, suggesting that laser therapy protocols should take into account fluencies, frequencies, and wavelengths of the laser before beginning treatment.

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.

L-NAME and L-arginine differentially ameliorate cigarette smoke-induced emphysema in mice.

Nitric oxide (NO) represents one of the most important intra- and extracellular mediators and takes part in both biologic and pathologic processes. This study aimed to verify the treatment with an NO inhibitor and an NO substrate in pulmonary emphysema induced by cigarette smoke (CS) in a murine model. We compared N-acetylcysteine (NAC), a precursor of glutathione, to G-nitro-L-arginine-methyl ester or L-NAME (LN), which is an NO inhibitor, and to l-arginine (LA), which is a substrate for NO formation. Mice were divided into several groups: control, CS, CS + LN, CS + LA, and CS + NAC. Control and CS groups were treated daily with a vehicle, while CS + LN, CS + LA, and CS + NAC groups were treated daily with LN (60 mg/kg), LA (120 mg/kg) and NAC (200 mg/kg), respectively. The bronchoalveolar lavage was analyzed and the lungs were removed for histological and biochemical analysis. CS increases neutrophil number. Neutrophil number was lowest in CS + LN, followed by CS + LA. The lungs of CS + LN, CS + LA and CS + NAC mice were protected compared to the lungs of CS mice, but not equal to the quality of lungs in control mice. The CS group also exhibited increased oxidative stress, which was also present in the CS + LN group and to a lesser extent in the CS + LA group. Tissue inhibitor of metalloproteinase 1 and 2 increased in the CS + LN group and to a lesser extent in the CS + LA group relative to the control group. These results suggest that LN and LA treatment protected the mouse lung from CS. However, NAC treatment was more than LN and LA. We suggest that the protection conferred by LN treatment requires a balance between proteases and antiproteases, and that protection conferred by LA treatment involves the balance between oxidants and antioxidants.

Mate tea ameliorates emphysema in cigarette smoke-exposed mice.

Exposure to cigarette smoke (CS) is associated with lung inflammation, oxidative stress, and emphysema. The aim of this work was to study Mate tea as a possible natural antioxidant resource against emphysema development. C57BL/6 mice were distributed into 4 groups: exposed to ambient air (control), exposed to the smoke of 12 cigarettes (CS), exposed to ambient air and treated with Mate (500 mg/kg/day diluted in 100 µL) (Mate), and exposed to CS and treated with Mate (CS+Mate). All mice were treated for 60 days. On day 61 the mice were killed. Right and left lungs were removed for histology and biochemical analysis, respectively. Emphysematous lesions and inflammatory cell influxes in the CS group were evident by histological analysis. Cells showed higher 4-hydroxynonenal labeling in the CS group than in the CS+Mate group. Myeloperoxidase activity was reduced in the CS+Mate group compared to the CS group. Superoxide dismutase and catalase activities were significantly higher in the CS+Mate group compared to the CS group. The ratio of reduced to oxidized glutathione was greater in the CS+Mate group than in the CS group. CS-induced emphysema in C57BL/6 mice was prevented by Mate in association with a reduction in inflammatory and oxidative stress parameters.

Grape skin extract reduced pulmonary oxidative response in mice exposed to cigarette smoke.

BACKGROUND: Oxidative stress has been implicated in the pathogenesis and progression of chronic obstructive pulmonary disease (COPD), and cigarette smoke (CS) is known to be one of the major sources of oxidants in the lungs. We postulated that acute administration of GSE (grape skin extract) would either reduce or protect the ALI (acute lung inflammation) produced by CS via NO release. MATERIAL/METHODS: We adopted a nutritional approach by investigating the inflammatory cells, metalloproteinase 9 (MMP-9) activity, and oxidative stress markers (superoxide dismutase - SOD; catalase - CAT; glutathione peroxidase (GPx) activities and malondialdehyde - MDA - levels) that play a role in the development of acute lung inflammation (ALI). Therefore, we tested an orally active antioxidant produced from grape skin manipulation (grape skin extract - GSE), in mice exposed to CS from 6 cigarettes a day for 5 days. In addition, we used a separate group treated with NG-nitro-L-arginine methyl ester (an NO inhibitor) to confirm nitric oxide (NO) involvement in GSE effects. RESULTS: We showed for the first time that administration of GSE inhibited ALI and oxidative damage induced by CS. This is associated with decreased MMP-9 activity, decreased number of inflammatory cells in the bronchoalveolar lavage fluid, and reduced levels of lipid peroxidation. Our results indicate that beneficial effects of GSE are NO-dependent. CONCLUSIONS: The study indicates that alteration of the oxidant-antioxidant balance is important in the pathogenesis of CS-induced ALI and suggests lung protective effects of GSE treatment in the mouse.

Endotoxin-induced acute lung injury is dependent upon oxidative response.

The aim of the present study was to investigate the involvement of oxidative stress in acute lung injury (ALI) induced by lipopolysaccharide (LPS) and its effects upon cell structure, function and inflammation. In total, 108 male C57BL/6 mice were divided into seven groups: CTR Group (50 µL of saline) administered intratracheally (i.t.), LPS 6 h (10 µg of LPS - i.t.), LPS 12 h (10 µg of LPS - i.t.), LPS 24 h (10 µg of LPS - i.t.), LPS 48 h (10 µg of LPS - i.t.), LPS 24 h (10 µg - i.t.) + NAC 40 mg/kg (gavage) and 24 h LPS (10 µg - i.t.) + NAC 100 mg/kg (gavage). The antioxidant treatment protected the lungs from stress in the first 12 h, but significant oxidative stress induction was observed at the 24-hour time point, and, after 48 h, there was no protection exerted by the antioxidant treatment. NAC (N-acetylcysteine) reversed the elastance parameters, and ΔP1 and ΔP2 compared with 24 h LPS alone. NAC reduced the number of inflammatory cells in histology analysis when compared with the 24 h LPS alone-treated group. NAC also inhibited the transcription of NFκB, IL-6, TNF-α and COX2 usually induced by LPS. Our results suggest that oxidative stress plays an important role in structural, functional and inflammatory responses in the ALI model.