RESUMO
Corticosteroid-resistant asthma (CRA) is a severe form of disease and clinically important, since patients do not respond to mainstay corticosteroid therapies. Thus, new therapies are needed. However, a big limiting factor in the understanding of CRA is the existence of different immunological and inflammatory phenotypes, a fact that makes it difficult to reproduce experimentally. Photobiomodulation (PBM) emerges as an alternative therapy based on earlier studies. This study aims to evaluate the effect of PBM using infrared light-emitting diode (ILED) on the development of corticosteroid-resistant asthma. Therefore, groups of rats were sensitized and challenged with ovalbumin plus Freund's adjuvant for the induction of CRA, and treated or not with ILED directly in the respiratory tract on the skin (wavelength 810 nm; power 100 mW; density energy 5 J/cm; total energy 15 J; time 150 s). Our experimental model was capable to induce neutrophilic asthma. Besides that, the corticosteroid treatment did not reverse the lung cell migration as well as the levels of leukotriene B4, and interleukins 17 and 6. The treatment with ILED reduced the lung cell migration; myeloperoxidase activity; mast cell degranulation; and the levels of leukotriene B4, thromboxane B2, prostaglandin E2, tumoral necrosis factor alpha, and interleukins 17 and 6. Still, ILED increased the level of interleukin 10. In conclusion, we showed promisor effects of ILED when irradiated directly in the respiratory tract as adjuvant treatment of corticosteroid-resistant asthma.
Assuntos
Asma , Terapia com Luz de Baixa Intensidade , Corticosteroides , Animais , Asma/tratamento farmacológico , Asma/radioterapia , Humanos , Pulmão , Mastócitos , Ratos , PeleRESUMO
Asthma is a chronic inflammatory disease characterized by recurrent and reversible episodes of wheezing, dyspnea, chest stiffness, and cough. Its treatment includes several drugs, high cost, and considerable side effects. Photobiomodulation (PBM) emerges as an alternative treatment, showing good results, and it can be applied locally or systemically. Here, we aim to evaluate the effect of transcutaneous systemic photobiomodulation (TSPBM) by red diode light. Therefore, adult rats were sensitized and challenged with ovalbumin (OVA) plus alum for induction of asthma and irradiated or not with TSPBM in the caudal vein (wavelength 660 ± 10 nm; total radiant emission 15 J; area 2.8 cm2; energy density 5.35 J/cm2; irradiance 33.3 mW/cm2; exposure time 150 s). Our investigations prioritized the cell migration into the alveolar space and lung, tracheal responsiveness, release and gene expression of cytokines, mast cell degranulation, and anaphylactic antibodies. Our results showed that TSPBM reduced the cell migration and mast cell degranulation without altering the tracheal responsiveness and ovalbumin antibody titers. Indeed, TSPBM increased the levels of interleukin 10 (IL-10) in the BAL fluid without altering the gene expression of cytokines in the lung tissue. Thus, this study showed that transcutaneous systemic irradiation reduced lung inflammation by altering mast cells degranulation and IL-10 level. Considering that this study is a pioneer in the used of light by the systemic route to treat asthma, the data are interesting and instigate future investigations, mainly in relation to the mechanisms involved and in dosimetry.
Assuntos
Asma , Pneumonia , Animais , Asma/tratamento farmacológico , Asma/radioterapia , Degranulação Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Interleucina-10/metabolismo , Pulmão/efeitos da radiação , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Teóricos , Ovalbumina/metabolismo , Ovalbumina/farmacologia , RatosRESUMO
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.
Assuntos
Asma , Interleucina-10 , Terapia com Luz de Baixa Intensidade , Animais , Anti-Inflamatórios/farmacologia , Asma/tratamento farmacológico , Asma/radioterapia , Linfócitos T CD4-Positivos , Modelos Animais de Doenças , Fatores de Transcrição Forkhead , Inflamação , Interleucina-10/metabolismo , Pulmão , Camundongos , Camundongos Endogâmicos BALB C , OvalbuminaRESUMO
Recent studies show that low-level laser therapy (LLLT) has an important anti-inflammatory action in acute lung inflammation. The present work explored if laser therapy is able to antagonize eosinophils and allergic inflammation induced by oxidative stress in Balb/c mice. Forty-eight hours after challenge, the leukocyte counting, ROS and nitrite/nitrate level, RANTES, CCL3, CCL8 as well as eotaxins were measured in the bronchoalveolar lavage fluid (BALF) of laser-treated mice or not. Into the lung, some chemokines receptors, the iNOS activity and mRNA expression, and the activities of superoxide dismutase (SOD), catalase, gluthatione, NADPH oxidase activities and thiobarbituric acid reactive species (T-Bars) were measured. Laser-treated allergic mice presented reduction of both the ICAM-1 and eosinophil in the lungs. RANTES, CCL8, CCL3 and eotaxins were reduced in BALF of laser-treated allergic mice. In allergic mice lung LLLT decreased the CCR1 and CCR3 and restored the oxidative stress balance as well. Laser decreased the lipidic peroxidation in allergic mice lung as much as increased SOD, GPx and GR. It shows that LLLT on allergic lung inflammation involves leukocyte-attractant chemokines and endogenous antioxidant. Based on results, LLLT may ultimately become a non- invasive option in allergic lung disease treatment. The top figure illustrates the laser decreasing the eosinophils migration into BALF and the bottom figure shows the laser upregulating the expression of heme-oxygenase (anti-oxidant enzyme) in lung tissue anti-oxidant.
Assuntos
Asma/radioterapia , Quimiocinas/metabolismo , Inflamação/radioterapia , Terapia com Luz de Baixa Intensidade , Estresse Oxidativo , Animais , Pulmão/fisiopatologia , Pulmão/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Low-level laser therapy (LLLT) controls bronchial hyperresponsiveness (BHR) associated with increased RhoA expression as well as pro-inflammatory mediators associated with NF-kB in acute lung inflammation. Herein, we explore if LLLT can reduce both BHR and Th2 cytokines in allergic asthma. Mice were studied for bronchial reactivity and lung inflammation after antigen challenge. BHR was measured through dose-response curves to acetylcholine. Some animals were pretreated with a RhoA inhibitor before the antigen. LLLT (660 nm, 30 mW and 5.4 J) was applied on the skin over the right upper bronchus and two irradiation protocols were used. Reduction of BHR post LLLT coincided with lower RhoA expression in bronchial muscle as well as reduction in eosinophils and eotaxin. LLLT also diminished ICAM expression and Th2 cytokines as well as signal transducer and activator of transduction 6 (STAT6) levels in lungs from challenged mice. Our results demonstrated that LLLT reduced BHR via RhoA and lessened allergic lung inflammation via STAT6.