Creatine supplementation impairs airway inflammation in an experimental model of asthma involving P2 × 7 receptor.

Creatine (Cr) is a substrate for adenosine triphosphate synthesis, and it is the most used dietary supplement among professional and recreative athletes and sportsmen. Creatine supplementation may increase allergic airway response, but the cellular and molecular mechanisms are unknown. We used murine model of OVA-induced chronic asthma and showed that Cr supplementation increased total proteins, ATP level, lymphocytes, macrophages, and IL-5 levels in BALF, as well as IL-5 in the supernatant of re-stimulated mediastinal lymph nodes. IL-5 and IL-13 expression by epithelial cells and by peribronchial leukocytes were increased by Cr. Cr augmented the expression of P2 × 7 receptor by peribronchial leukocytes and by epithelial cells, and increased the accumulation of eosinophils in peribronchial space and of collagen fibers in airway wall. In human cells, while Cr induced a release of ATP, IL-6, and IL-8 from BEAS-2B cells, whole blood cells, such as eosinophils, and CD4+ T cells, P2 × 7 receptor inhibitor (A740003) reduced such effects, as denoted by reduced levels of ATP, IL-6, and IL-8. Therefore, Cr supplementation worsened asthma pathology due to activation of airway epithelial cells and peribronchial leukocytes, involving purinergic signaling.

Aerobic exercise inhibits acute lung injury: from mouse to human evidence Exercise reduced lung injury markers in mouse and in cells.

Acute respiratory distress syndrome (ARDS) is defined as hypoxemic respiratory failure with intense pulmonary inflammation, involving hyperactivation of endothelial cells and neutrophils. Given the anti-inflammatory effects of aerobic exercise (AE), this study investigated whether AE performed daily for 5 weeks would inhibit extra-pulmonary LPS-induced ARDS. C57Bl/6 mice were distributed into Control, Exercise, LPS and Exercise+LPS groups. AE was performed on a treadmill for 5x/week for four weeks before LPS administration. 24hours after the final AE physical test, animals received 100ug of LPS intra-peritoneally. In addition, whole blood cell culture, neutrophils and human endothelial cells were preincubated with IL-10, an anti-inflammatory cytokine induced by exercise. AE reduced total protein levels (p<0.01) and neutrophil accumulation in bronchoalveolar lavage (BAL) (p<0.01) and lung parenchyma (p<0.01). AE reduced BAL inflammatory cytokines IL-1ß, IL-6 and GM-CSF (p<0.001), CXCL1/KC, IL-17, TNF-alpha and IGF-1 (p<0.01). Systemically, AE reduced IL-1ß, IL-6 and IFN-gamma (p<0.001), CXCL1/KC (p<0.01) and TNF-alpha (p<0.05). AE increased IL-10 levels in serum (p<0.001) and BAL (p<0.001). Furthermore, AE increased superoxide dismutase SOD (p<0.01) and decreased superoxide anion accumulation in the lungs (p<0.01). Lastly, pre-incubation with IL-10 significantly reduced LPS-induced activation of whole blood cells, neutrophils and HUVECs, as observed by reduced production of IL-1ß, IL-6, IL-8 and TNF-alpha. Our data suggest that AE inhibited LPS-induced lung inflammation by attenuating inflammatory cytokines and oxidative stress markers in mice and human cell culture via enhanced IL-10 production.

Photobiomodulation Therapy Restores IL-10 Secretion in a Murine Model of Chronic Asthma: Relevance to the Population of CD4+CD25+Foxp3+ Cells in Lung.

It is largely known that photobiomodulation (PBM) has beneficial effects on allergic pulmonary inflammation. Our previous study showed an anti-inflammatory effect of the PBM in an acute experimental model of asthma, and we see that this mechanism is partly dependent on IL-10. However, it remains unclear whether the activation of regulatory T cells is mediated by PBM in a chronic experimental model of asthma. In this sense, the objective of this study was to verify the anti-inflammatory role of the PBM in the pulmonary inflammatory response in a chronic experimental asthma model. The protocol used for asthma induction was the administration of OVA subcutaneously (days 0 and 14) and intranasally (3 times/week, for 5 weeks). On day 50, the animals were sacrificed for the evaluation of the different parameters. The PBM used was the diode, with a wavelength of 660 nm, a power of 100 mW, and 5 J for 50 s/point, in three different application points. Our results showed that PBM decreases macrophages, neutrophils, and lymphocytes in the bronchoalveolar lavage fluid (BALF). Moreover, PBM decreased the release of cytokines by the lung, mucus, and collagen in the airways and pulmonary mechanics. When we analyzed the percentage of Treg cells in the group irradiated with laser, we verified an increase in these cells, as well as the release of IL-10 in the BALF. Therefore, we conclude that the use of PBM therapy in chronic airway inflammation attenuated the inflammatory process, as well as the pulmonary functional and structural parameters, probably due to an increase in Treg cells.

Low-level laser therapy attenuates lung inflammation and airway remodeling in a murine model of idiopathic pulmonary fibrosis: Relevance to cytokines secretion from lung structural cells.

Idiopathic pulmonary fibrosis (IPF) is a progressive and chronic inflammatory disease with a poor prognosis and very few available treatment options. Low-level laser therapy (LLLT) has been gaining prominence as a new and effective anti-inflammatory and immunomodulatory agent. Can lung inflammation and the airway remodeling be regulated by LLLT in an experimental model of IPF in C57Bl/6 mice? The present study investigated if laser attenuates cellular migration to the lungs, the airway remodeling as well as pro-fibrotic cytokines secretion from type II pneumocytes and fibroblasts. Mice were irradiated (780 nm and 30 mW) and then euthanized fifteen days after bleomycin-induced lung fibrosis. Lung inflammation and airway remodeling were evaluated through leukocyte counting in bronchoalveolar lavage fluid (BALF) and analysis of collagen in lung, respectively. Inflammatory cells in blood were also measured. For in vitro assays, bleomycin-activated fibroblasts and type II pneumocytes were irradiated with laser. The pro- and anti-inflammatory cytokines level in BALF as well as cells supernatant were measured by ELISA, and the TGFß in lung was evaluated by flow cytometry. Lung histology was used to analyze collagen fibers around the airways. LLLT reduced both migration of inflammatory cells and deposition of collagen fibers in the lungs. In addition, LLLT downregulated pro-inflammatory cytokines and upregulated the IL-10 secretion from fibroblasts and pneumocytes. Laser therapy greatly reduced total lung TGFß. Systemically, LLLT also reduced the inflammatory cells counted in blood. There is no statistical difference in inflammatory parameters studied between mice of the basal group and the laser-treated mice. Data obtained indicate that laser effectively attenuates the lung inflammation, and the airway remodeling in experimental pulmonary fibrosis is driven to restore the balance between the pro- and anti-inflammatory cytokines in lung and inhibit the pro-fibrotic cytokines secretion from fibroblasts.

The role of periodontal treatment associated with photodynamic therapy on the modulation of systemic inflammation in the experimental model of asthma and periodontitis.

BACKGROUND: The association of Periodontitis (P) with several systemic diseases, among them asthma (A), has been previously studied. As periodontal treatment (TTO) associated with photodynamic therapy (PDT) is able to treat P, the aim of this study is to verify whether periodontitis exerts systemic effects on asthma, and whether TTO, associated or not with PDT, is capable of altering the systemic course of both pathologies. METHODS: 64 male Balb/c mice were divided into 8 groups (n = 8): Basal (B), P, P + TTO, P + TTO + PDT, Asthma, A + P, A + P + TTO, A + P + TTO + PDT. After 43 days, all animals were euthanized. The total and differential leukocyte count in serum, platelet count, alveolar bronchial lavage cell count, femoral lavage cell count in addition to the reactivity of the trachea, lung edema and gingiva cytokines were analyzed. The frequency of inflammatory cells was assessed via flow cytometry. One-way ANOVA test was used, followed by the Student-Newman-Keuls post-test. RESULTS: There was an increase in the number of blood circulating eosinophils in group A when compared to group B (p < 0.01); this characterized the asthma experimental model. P (p < 0.05) presented a lower amount of cytokine TNF-α in the gingiva when compared to the Asthma group. Apart from that, there was no statistical difference found for the other analyzed parameters. CONCLUSION: These data contributed to elucidate that P and A, associated or not with TTO and PDT, are not able to interfere with the systemic parameters of Balb/c mice.

Effect of Low-Level Laser Therapy (LLLT) in Pulmonary Inflammation in Asthma Induced by House Dust Mite (HDM): Dosimetry Study.

Asthma is characterized by chronic inflammation in the airways. Several models have been proposed for the discovery of new therapies. Low-Level Laser Therapy (LLLT) is relatively new and effective, very low cost, with no side effects. However, there is still no consensus on the optimal dose to be used. In this sense, the objective of the present study was to evaluate the best dose in an experimental model of asthma induced by House Dust Mite (HDM). Balb/c mice received administration of 100 ug/animal HDM and LLLT applications (diode laser: 660 nm, 100 mW and four different energies 1J, 3J, 5J, and 7.5J) for 16 days. After 24 hours, we studied inflammatory, functional, and structural parameters. The results showed that LBI was able to modulate the pulmonary inflammation observed by reducing the number of cells in Bronchoalveolar Lavage Fluid (BALF) as well as reducing the percentage of neutrophils, eosinophils and T lymphocytes. On the other hand, LLLT increased the level of IL-10 and reduced levels of IL-4, IL-5 and IL-13 in BALF. LLLT was able to reduce the production of mucus, peribronchial eosinophils, collagen deposition, bronchoconstriction index, and bronchial and muscular thickening in the airways. We concluded that the use of LLLT in the treatment of chronic inflammation of the airways attenuated the inflammatory process and functional and structural parameters. We emphasize, in general, that the 1J and 3J laser presented better results. Thus, photobiomodulation may be considered a promising tool for the treatment of chronic pulmonary allergic inflammation observed in asthma.

Montelukast, Leukotriene Inhibitor, Reduces LPS-Induced Acute Lung Inflammation and Human Neutrophil Activation.

OBJECTIVES: Some pro-inflammatory lipids derived from 1 lipooxygenase enzyme are potent neutrophil chemoattractant, a cell centrally involved in acute respiratory distress syndrome (ARDS); a syndrome lacking effective treatment. Considering the beneficial effects of the leukotriene receptor inhibitor, montelukast, on other lung diseases, whether montelukast attenuates inflammation in a mouse model of ARDS, and whether it reduces LPS stimulated activation of human neutrophils was investigated. METHODS: Thirty-five C57Bl/6 mice were distributed into control (PBS)+24h, LPS+24h (10µg/mouse), control+48h, LPS+48h, and LPS 48h+Montelukast (10mg/kg). In addition, human neutrophils were incubated with LPS (1µg/mL) and treated with montelukast (10µM). RESULTS: Oral-tracheal administration of montelukast significantly attenuated total cells (P<.05), macrophages (P<.05), neutrophils (P<.01), lymphocytes (P<.001) and total protein levels in BAL (P<.05), as well as IL-6 (P<.05), CXCL1/KC (P<.05), IL-17 (P<.05) and TNF-α (P<.05). Furthermore, montelukast reduced neutrophils (P<.001), lymphocytes (P<.01) and macrophages (P<.01) in the lung parenchyma. In addition, montelukast restored BAL VEGF levels (P<.05). LTB4 receptor expression (P<.001) as well as NF-κB (P<.001), a downstream target of LPS, were also reduced in lung parenchymal leukocytes. Furthermore, montelukast reduced IL-8 (P<.001) production by LPS-treated human neutrophils. CONCLUSION: In conclusion, montelukast efficiently attenuated both LPS-induced lung inflammation in a mouse model of ARDS and in LPS challenged human neutrophils.

Aerobic Exercise Protects from Pseudomonas aeruginosa-Induced Pneumonia in Elderly Mice.

BACKGROUND: Pseudomonas aeruginosa (PS) infection results in severe morbidity and mortality, especially in immune-deficient populations. Aerobic exercise (AE) modulates the immune system, but its effects on the outcomes of pulmonary PS infection in elderly mice are unknown. METHODS: BALB/c mice (24 weeks old) were randomized to sedentary, exercise (EX), PS, and PS + EX groups for the acute experimental setting, and PS and PS + EX groups for the chronic setting. Low-intensity AE was performed for 5 weeks, 60 min/day; 24 h after the final AE session, mice were inoculated with 5 × 104 colony-forming units (CFU) of PS, and 24 h and 14 days after PS inoculation, mice were studied. RESULTS: AE inhibited PS colonization (p < 0.001) and lung inflammation (total cells, neutrophils, lymphocytes [p < 0.01] in bronchoalveolar lavage [BAL]), with significant differences in BAL levels of IL-1ß (p < 0.001), IL-6 (p < 0.01), CXCL1 (p < 0.001), and TNF-α (p < 0.001), as well as parenchymal neutrophils (p < 0.001). AE increased BAL levels of IL-10 and parenchymal (p < 0.001) and epithelial (p < 0.001) IL-10 expression, while epithelial (p < 0.001) and parenchymal (p < 0.001) NF-κB expression was decreased. AE diminished pulmonary lipid peroxidation (p < 0.001) and increased glutathione peroxidase (p < 0.01). Pre-incubation of BEAS-2B with IL-10 inhibited PS-induced epithelial cell expression of TNF-α (p < 0.05), CD40 (p < 0.01), and dichlorodihydrofluorescein diacetate (p < 0.05). CONCLUSIONS: AE inhibits PS-induced lung inflammation and bacterial colonization in elderly mice, involving IL-10/NF-κB, and redox signaling.

Effects of periodontitis on the development of asthma: The role of photodynamic therapy.

To evaluate whether periodontitis modulates lung inflammation in an experimental model of asthma as well as the photodynamic therapy (PDT) is associated with a reduction of lung inflammation. Seventy-two BALB/c male mice (~2 months) were randomly divided into 8 groups (n = 9): Basal, Periodontitis (P), P+PT, P+PT+PDT, Asthma (A), A+P, A+P+PT, and A+P+PT+PDT. Periodontitis was induced by using the ligature technique and asthma was induced by ovalbumin (OVA). PT was performed with curettes and PDT with methylene blue (0.005%), λ = 660nm, with a radiant exposure of 318J/cm2. After 43 days, euthanasia was carried out prior to lung and mandible morphological analyzes. All of the manipulations of the animals were performed by only one operator. The total and differential cell counts and cytokines IL-4, IL-5, IL-10, IFN-γ, TNF-α, IL-1ß, and IL-6 were evaluated in the bronchoalveolar lavage (BAL) and in the serum. Mucus and alkaline phosphatase were also quantified. Statistical analyzes were performed by a blinded statistician. One-way analysis of variance (ANOVA) was employed, followed by the Student-Newman-Keuls test. Periodontitis group (P) increased alkaline phosphatase and bone resorption (p<0.05), validating the experimental model of periodontitis. The A group and the P group increased the total amount of cells (p <0.05) in the BAL. However, in the A+P group, there was a decrease in these cells, except for in the A+P+PT+PDT group (p<0.05). The asthma group increased the Th2 cytokines and P group increased the Th1 cytokine profile, and A+P+PT+PDT group increased IL-10 cytokine. Mucus was increased for the A and P groups. In conclusion, periodontitis in the asthmatic mice reduced the inflammatory migrated cells in the BAL (eosinophils, lymphocytes, macrophages). In addition, it reduced the levels of the IL-4 and TNF-α cytokines, which was also accompanied by a decreased mucus production. After PDT treatment the total cell count increased however, this increase was not accompanied by a pro-inflammatory cytokines release. Only in PDT group the anti-inflammatory IL-10 was increased. Further studies are needed to understand this mechanism of action.

Exercise Reduces Lung Fibrosis Involving Serotonin/Akt Signaling.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a chronic fibrosing interstitial pneumonia, which involves aberrant serotonin (5-hydroxytryptamine [5-HT]) and Akt signaling. As protective effects of chronic aerobic training (AT) have been demonstrated in the context of lung injury, this study investigated whether AT attenuates bleomycin-induced lung fibrosis partly via a reduction of 5-HT and AKT signaling. METHODS: Seventy-two C57BL/6 male mice were distributed in Control (Co), Exercise (Ex), Fibrosis (Fi), and Fibrosis + Exercise (Fi + Ex) groups. Bleomycin (1.5 UI·kg) was administered on day 1 and treadmill AT began on day 15 and continued for 60 min·d, 5 d·wk for 4 wk. We evaluated total and differential cell counts in bronchoalveolar lavage (BAL), interleukin (IL)-1ß, IL-6, CXCL1/KC, IL-10, tumor necrosis factor α, and transforming growth factor ß levels in BAL, collagen content in lung parenchyma, 5-HT levels in BAL fluid and in serum, the expression of 5-HT2B receptor, and Akt phosphorylation in lung tissue. RESULTS: AT reduced bleomycin-increased number of total cells (P < 0.001), neutrophils (P < 0.01), macrophages (P < 0.01), and lymphocytes (P < 0.05) in BAL. It also reduced the levels of IL-1ß (P < 0.01), IL-6 (P < 0.05), CXCL1/KC (P < 0.001), tumor necrosis factor α (P < 0.001), and transforming growth factor ß (P < 0.001). It increased expression of ant-inflammatory cytokine IL-10 (P < 0.001). It reduced bleomycin-increased 5-HT levels in BAL (P < 0.001) and in serum (P < 0.05). Reductions in collagen fiber deposition (P < 0.01), 5-HT2B receptor expression (P < 0.01), and Akt phosphorylation in lung tissue were observed. CONCLUSIONS: AT accelerates the resolution of lung inflammation and fibrosis in a model of bleomycin-induced lung fibrosis partly via attenuation of 5-HT/Akt signaling.

Low level laser therapy reduces acute lung inflammation in a model of pulmonary and extrapulmonary LPS-induced ARDS.

The present study aimed to investigate the effects low level laser therapy (LLLT) in a LPS-induced pulmonary and extrapulmonary acute respiratory distress syndrome (ARDS) in BALB/c mice. Laser (830nm laser, 9J/cm(2), 35mW, 80s per point, 3 points per application) was applied in direct contact with skin, 1h after LPS administration. Mice were distributed in control (n=6; PBS), ARDS IT (n=7; LPS orotracheally 10µg/mouse), ARDS IP (n=7; LPS intra-peritoneally 100µg/mouse), ARDS IT+Laser (n=9; LPS intra-tracheally 10µg/mouse), ARDS IP+Laser (n=9; LPS intra-peritoneally 100µg/mouse). Twenty-four hours after last LPS administration, mice were studied for pulmonary inflammation by total and differential cell count in bronchoalveolar lavage (BAL), cytokines (IL-1beta, IL-6, KC and TNF-alpha) levels in BAL fluid and also by quantitative analysis of neutrophils number in the lung parenchyma. LLLT significantly reduced pulmonary and extrapulmonary inflammation in LPS-induced ARDS, as demonstrated by reduced number of total cells (p<0.001) and neutrophils (p<0.001) in BAL, reduced levels of IL-1beta, IL-6, KC and TNF-alpha in BAL fluid and in serum (p<0.001), as well as the number of neutrophils in lung parenchyma (p<0.001). LLLT is effective to reduce pulmonary inflammation in both pulmonary and extrapulmonary model of LPS-induced ARDS.