RESUMO
We compared the effects of bone marrow-derived mononuclear cells (BMMCs) and mesenchymal stromal cells (MSCs) on airway inflammation and remodeling and lung mechanics in experimental allergic asthma. C57BL/6 mice were sensitized and challenged with ovalbumin (OVA group). A control group received saline using the same protocol. Twenty-four hours after the last challenge, groups were further randomized into subgroups to receive saline, BMMCs (2×10(6)) or MSCs (1×10(5)) intratracheally. BMMC and MSC administration decreased cell infiltration, bronchoconstriction index, alveolar collapse, collagen fiber content in the alveolar septa, and interleukin (IL)-4, IL-13, transforming growth factor (TGF)-ß and vascular endothelial growth factor (VEGF) levels compared to OVA-SAL. Lung function, alveolar collapse, collagen fiber deposition in alveolar septa, and levels of TGF-ß and VEGF improved more after BMMC than MSC therapy. In conclusion, intratracheal BMMC and MSC administration effectively modulated inflammation and fibrogenesis in an experimental model of asthma, but BMMCs was associated with greater benefit in terms of reducing levels of fibrogenesis-related growth factors.
Assuntos
Asma/patologia , Células da Medula Óssea/patologia , Leucócitos Mononucleares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Análise de Variância , Animais , Antígenos CD/metabolismo , Asma/induzido quimicamente , Asma/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ovalbumina/imunologiaRESUMO
We hypothesized that the route of administration would impact the beneficial effects of bone marrow-derived mononuclear cell (BMDMC) therapy on the remodelling process of asthma. C57BL/6 mice were randomly assigned to two main groups. In the OVA group, mice were sensitized and challenged with ovalbumin, while the control group received saline using the same protocol. Twenty-four hours before the first challenge, control and OVA animals were further randomized into three subgroups to receive saline (SAL), BMDMCs intravenously (2×10(6)), or BMDMCs intratracheally (2×10(6)). The following changes were induced by BMDMC therapy in OVA mice regardless of administration route: reduction in resistive and viscoelastic pressures, static elastance, eosinophil infiltration, collagen fibre content in airways and lung parenchyma; and reduction in the levels of interleukin (IL)-4, IL-13, transforming growth factor-ß and vascular endothelial growth factor. In conclusion, BMDMC modulated inflammatory and remodelling processes regardless of administration route in this experimental model of allergic asthma.
Assuntos
Asma/patologia , Asma/terapia , Transplante de Medula Óssea/métodos , Leucócitos Mononucleares/transplante , Administração Intravenosa , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia Eletrônica de TransmissãoRESUMO
We hypothesized that bone marrow-derived mononuclear cell (BMDMC) therapy protects the lung and consequently the heart in experimental elastase-induced emphysema. Twenty-four female C57BL/6 mice were intratracheally instilled with saline (C group) or porcine pancreatic elastase (E group) once a week during 4 weeks. C and E groups were randomized into subgroups receiving saline (SAL) or male BMDMCs (2 × 10(6), CELL) intravenously 3h after the first saline or elastase instillation. Compared to E-SAL group, E-CELL mice showed, at 5 weeks: lower mean linear intercept, neutrophil infiltration, elastolysis, collagen fiber deposition in alveolar septa and pulmonary vessel wall, lung cell apoptosis, right ventricle wall thickness and area, higher endothelial growth factor and insulin-like growth factor mRNA expressions in lung tissue, and reduced platelet-derived growth factor, transforming growth factor-ß, and caspase-3 expressions. In conclusion, BMDMC therapy was effective at modulating the inflammatory and remodeling processes in the present model of elastase-induced emphysema.
Assuntos
Enfisema/terapia , Leucócitos Mononucleares/transplante , Pulmão/patologia , Doença Cardiopulmonar/prevenção & controle , Remodelação das Vias Aéreas , Análise de Variância , Animais , Células da Medula Óssea/citologia , Caspase 3/metabolismo , Ecocardiografia , Enfisema/induzido quimicamente , Enfisema/metabolismo , Enfisema/patologia , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pulmão/metabolismo , Subpopulações de Linfócitos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Elastase Pancreática , Distribuição AleatóriaRESUMO
PURPOSE: We hypothesized that: (1) intraabdominal hypertension increases pulmonary inflammatory and fibrogenic responses in acute lung injury (ALI); (2) in the presence of intraabdominal hypertension, higher tidal volume reduces lung damage in extrapulmonary ALI, but not in pulmonary ALI. METHODS: Wistar rats were randomly allocated to receive Escherichia coli lipopolysaccharide intratracheally (pulmonary ALI) or intraperitoneally (extrapulmonary ALI). After 24 h, animals were randomized into subgroups without or with intraabdominal hypertension (15 mmHg) and ventilated with positive end expiratory pressure = 5 cmH(2)O and tidal volume of 6 or 10 ml/kg during 1 h. Lung and chest wall mechanics, arterial blood gases, lung and distal organ histology, and interleukin (IL)-1ß, IL-6, caspase-3 and type III procollagen (PCIII) mRNA expressions in lung tissue were analyzed. RESULTS: With intraabdominal hypertension, (1) chest-wall static elastance increased, and PCIII, IL-1ß, IL-6, and caspase-3 expressions were more pronounced than in animals with normal intraabdominal pressure in both ALI groups; (2) in extrapulmonary ALI, higher tidal volume was associated with decreased atelectasis, and lower IL-6 and caspase-3 expressions; (3) in pulmonary ALI, higher tidal volume led to higher IL-6 expression; and (4) in pulmonary ALI, liver, kidney, and villi cell apoptosis was increased, but not affected by tidal volume. CONCLUSIONS: Intraabdominal hypertension increased inflammation and fibrogenesis in the lung independent of ALI etiology. In extrapulmonary ALI associated with intraabdominal hypertension, higher tidal volume improved lung morphometry with lower inflammation in lung tissue. Conversely, in pulmonary ALI associated with intraabdominal hypertension, higher tidal volume increased IL-6 expression.
Assuntos
Lesão Pulmonar Aguda/imunologia , Hipertensão Intra-Abdominal/imunologia , Fibrose Pulmonar/etiologia , Volume de Ventilação Pulmonar/fisiologia , Lesão Pulmonar Aguda/patologia , Análise de Variância , Animais , Apoptose/efeitos dos fármacos , Colágeno Tipo III , Citocinas/imunologia , Escherichia coli , Infusões Parenterais , Hipertensão Intra-Abdominal/complicações , Intubação Intratraqueal , Lipopolissacarídeos/administração & dosagem , Respiração com Pressão Positiva/métodos , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
We analysed the effects of oleanolic acid (OA) on lung mechanics and histology and its possible mechanisms of action in experimental acute lung injury (ALI). BALB/c mice were randomly divided into Control (saline, ip) and ALI (paraquat, 25 mg/kg, ip) groups. At 1 h, both groups were treated with saline (SAL, 50 µl ip), OA (10 mg/kg ip), or dexamethasone (DEXA, 1 mg/kg ip). At 24 h, lung static elastance, viscoelastic pressure, and alveolar collapse reduced more after OA compared to DEXA administration. Tumour necrosis factor-α, macrophage migration inhibitory factor, interleukin-6, interferon-γ, and transforming growth factor-ß mRNA expressions in lung tissue diminished similarly after OA or DEXA. Conversely, only OA avoided reactive oxygen species generation and yielded a significant decrease in nitrite concentration. OA and DEXA restored the reduced glutathione/oxidized glutathione ratio and catalase activity while increasing glutathione peroxidase induced by paraquat. In conclusion, OA improved lung morphofunction by modulating the release of inflammatory mediators and oxidative stress.
Assuntos
Lesão Pulmonar Aguda/imunologia , Anti-Inflamatórios/farmacologia , Pulmão/efeitos dos fármacos , Ácido Oleanólico/farmacologia , Mecânica Respiratória/efeitos dos fármacos , Lesão Pulmonar Aguda/patologia , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiocinas/análise , Quimiocinas/biossíntese , Modelos Animais de Doenças , Inflamação/imunologia , Inflamação/patologia , Pulmão/imunologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/imunologia , Mecânica Respiratória/imunologiaRESUMO
We tested the hypothesis that bone marrow-derived mononuclear cells (BMDMCs) at an early phase of cecal ligation and puncture (CLP)-induced sepsis may have lasting effects on: (1) lung mechanics and histology, (2) the structural remodelling of lung parenchyma, (3) lung, kidney, and liver cell apoptosis, and (4) pro- and anti-inflammatory cytokines and growth factors. At day 1, BMDMC significantly reduced mortality, as well as caspase-3, interleukin (IL)-6 and IL-1ß, vascular endothelial growth factor, platelet-derived growth factor, hepatocyte growth factor, and transforming growth factor-ß, but increased IL-10 mRNA expression in lung tissue in septic mice contributing to endothelium and epithelium alveolar repair and improvement of lung mechanics. BMDMC also prevented the increase of apoptotic cells in lung, liver, and kidney. At day 7, these early functional and morphological effects were preserved or further improved. In conclusion, in the present model of sepsis, the beneficial effects of early administration of BMDMCs on lung and distal organs were preserved, possibly by paracrine mechanisms.
Assuntos
Transplante de Medula Óssea , Leucócitos Mononucleares/transplante , Pulmão/cirurgia , Sepse/cirurgia , Animais , Transplante de Medula Óssea/métodos , Transplante de Células/métodos , Citocinas/biossíntese , Feminino , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Sepse/metabolismo , Sepse/patologia , Fatores de TempoRESUMO
OBJECTIVE: To investigate the effects of the rate of airway pressure increase and duration of recruitment maneuvers on lung function and activation of inflammation, fibrogenesis, and apoptosis in experimental acute lung injury. DESIGN: Prospective, randomized, controlled experimental study. SETTING: University research laboratory. SUBJECTS: Thirty-five Wistar rats submitted to acute lung injury induced by cecal ligation and puncture. INTERVENTIONS: After 48 hrs, animals were randomly distributed into five groups (seven animals each): 1) nonrecruited (NR); 2) recruitment maneuvers (RMs) with continuous positive airway pressure (CPAP) for 15 secs (CPAP15); 3) RMs with CPAP for 30 secs (CPAP30); 4) RMs with stepwise increase in airway pressure (STEP) to targeted maximum within 15 secs (STEP15); and 5) RMs with STEP within 30 secs (STEP30). To perform STEP RMs, the ventilator was switched to a CPAP mode and positive end-expiratory pressure level was increased stepwise. At each step, airway pressure was held constant. RMs were targeted to 30 cm H2O. Animals were then ventilated for 1 hr with tidal volume of 6 mL/kg and positive end-expiratory pressure of 5 cm H2O. MEASUREMENTS AND MAIN RESULTS: Blood gases, lung mechanics, histology (light and electronic microscopy), interleukin-6, caspase 3, and type 3 procollagen mRNA expressions in lung tissue. All RMs improved oxygenation and lung static elastance and reduced alveolar collapse compared to NR. STEP30 resulted in optimal performance, with: 1) improved lung static elastance vs. NR, CPAP15, and STEP15; 2) reduced alveolar-capillary membrane detachment and type 2 epithelial and endothelial cell injury scores vs. CPAP15 (p < .05); and 3) reduced gene expression of interleukin-6, type 3 procollagen, and caspase 3 in lung tissue vs. other RMs. CONCLUSIONS: Longer-duration RMs with slower airway pressure increase efficiently improved lung function, while minimizing the biological impact on lungs.
Assuntos
Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/terapia , Pressão Positiva Contínua nas Vias Aéreas/métodos , Pulmão/metabolismo , Lesão Pulmonar Aguda/complicações , Lesão Pulmonar Aguda/mortalidade , Animais , Caspase 3/análise , Caspase 3/metabolismo , Modelos Animais de Doenças , Interleucina-6/análise , Interleucina-6/metabolismo , Pulmão/fisiopatologia , Masculino , Microscopia Eletrônica de Transmissão , Pró-Colágeno , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Mecânica Respiratória , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Sepse/complicações , Taxa de Sobrevida , Fatores de TempoRESUMO
We hypothesized that bone marrow-derived mononuclear cells (BMDMC) would attenuate the remodeling process in a chronic allergic inflammation model. C57BL/6 mice were assigned to two groups. In OVA, mice were sensitized and repeatedly challenged with ovalbumin. Control mice (C) received saline under the same protocol. C and OVA were further randomized to receive BMDMC (2 × 106) or saline intravenously 24 h before the first challenge. BMDMC therapy reduced eosinophil infiltration, smooth muscle-specific actin expression, subepithelial fibrosis, and myocyte hypertrophy and hyperplasia, thus causing a decrease in airway hyperresponsiveness and lung mechanical parameters. BMDMC from green fluorescent protein (GFP)-transgenic mice transplanted into GFP-negative mice yielded lower engraftment in OVA. BMDMC increased insulin-like growth factor expression, but reduced interleukin-5, transforming growth factor-ß, platelet-derived growth factor, and vascular endothelial growth factor mRNA expression. In conclusion, in the present chronic allergic inflammation model, BMDMC therapy was an effective pre-treatment protocol that potentiated airway epithelial cell repair and prevented inflammatory and remodeling processes.
Assuntos
Remodelação das Vias Aéreas/fisiologia , Células da Medula Óssea/fisiologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Tecido Conjuntivo/fisiologia , Leucócitos Mononucleares/fisiologia , Hipersensibilidade Respiratória/terapia , Análise de Variância , Animais , Líquido da Lavagem Broncoalveolar , Doença Crônica , Tecido Conjuntivo/ultraestrutura , Modelos Animais de Doenças , Feminino , Injeções Intravenosas/métodos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interleucina-5/metabolismo , Pulmão/patologia , Pulmão/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão/métodos , Ovalbumina/imunologia , Hipersensibilidade Respiratória/etiologia , Hipersensibilidade Respiratória/patologiaRESUMO
OBJECTIVE: In acute lung injury, recruitment maneuvers have been used to open collapsed lungs and set positive end-expiratory pressure, but their effectiveness may depend on the degree of lung injury. This study uses a single experimental model with different degrees of lung injury and tests the hypothesis that recruitment maneuvers may have beneficial or deleterious effects depending on the severity of acute lung injury. We speculated that recruitment maneuvers may worsen lung mechanical stress in the presence of alveolar edema. DESIGN: Prospective, randomized, controlled experimental study. SETTING: University research laboratory. SUBJECTS: Thirty-six Wistar rats randomly divided into three groups (n = 12 per group). INTERVENTIONS: In the control group, saline was intraperitoneally injected, whereas moderate and severe acute lung injury animals received paraquat intraperitoneally (20 mg/kg [moderate acute lung injury] and 25 mg/kg [severe acute lung injury]). After 24 hrs, animals were further randomized into subgroups (n = 6/each) to be recruited (recruitment maneuvers: 40 cm H2O continuous positive airway pressure for 40 secs) or not, followed by 1 hr of protective mechanical ventilation (tidal volume, 6 mL/kg; positive end-expiratory pressure, 5 cm H2O). MEASUREMENTS AND MAIN RESULTS: Only severe acute lung injury caused alveolar edema. The amounts of alveolar collapse were similar in the acute lung injury groups. Static lung elastance, viscoelastic pressure, hyperinflation, lung, liver, and kidney cell apoptosis, and type 3 procollagen and interleukin-6 mRNA expressions in lung tissue were more elevated in severe acute lung injury than in moderate acute lung injury. After recruitment maneuvers, static lung elastance, viscoelastic pressure, and alveolar collapse were lower in moderate acute lung injury than in severe acute lung injury. Recruitment maneuvers reduced interleukin-6 expression with a minor detachment of the alveolar capillary membrane in moderate acute lung injury. In severe acute lung injury, recruitment maneuvers were associated with hyperinflation, increased apoptosis of lung and kidney, expression of type 3 procollagen, and worsened alveolar capillary injury. CONCLUSIONS: In the presence of alveolar edema, regional mechanical heterogeneities, and hyperinflation, recruitment maneuvers promoted a modest but consistent increase in inflammatory and fibrogenic response, which may have worsened lung function and potentiated alveolar and renal epithelial injury.
Assuntos
Lesão Pulmonar Aguda/terapia , Pressão Positiva Contínua nas Vias Aéreas , Atelectasia Pulmonar/etiologia , Edema Pulmonar/etiologia , Lesão Pulmonar Aguda/complicações , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/fisiopatologia , Animais , Colágeno Tipo III/biossíntese , Interleucina-6/biossíntese , Rim/patologia , Fígado/patologia , Pulmão/patologia , Microscopia Eletrônica de Transmissão , Alvéolos Pulmonares/lesões , Alvéolos Pulmonares/patologia , Alvéolos Pulmonares/fisiopatologia , Atelectasia Pulmonar/terapia , Edema Pulmonar/terapia , Ratos , Ratos Wistar , Respiração Artificial , Mecânica Respiratória/fisiologiaRESUMO
INTRODUCTION: Recruitment maneuvers (RMs) seem to be more effective in extrapulmonary acute lung injury (ALI), caused mainly by sepsis, than in pulmonary ALI. Nevertheless, the maintenance of adequate volemic status is particularly challenging in sepsis. Since the interaction between volemic status and RMs is not well established, we investigated the effects of RMs on lung and distal organs in the presence of hypovolemia, normovolemia, and hypervolemia in a model of extrapulmonary lung injury induced by sepsis. METHODS: ALI was induced by cecal ligation and puncture surgery in 66 Wistar rats. After 48 h, animals were anesthetized, mechanically ventilated and randomly assigned to 3 volemic status (n = 22/group): 1) hypovolemia induced by blood drainage at mean arterial pressure (MAP) approximately 70 mmHg; 2) normovolemia (MAP approximately 100 mmHg), and 3) hypervolemia with colloid administration to achieve a MAP approximately 130 mmHg. In each group, animals were further randomized to be recruited (CPAP = 40 cm H2O for 40 s) or not (NR) (n = 11/group), followed by 1 h of protective mechanical ventilation. Echocardiography, arterial blood gases, static lung elastance (Est,L), histology (light and electron microscopy), lung wet-to-dry (W/D) ratio, interleukin (IL)-6, IL-1beta, caspase-3, type III procollagen (PCIII), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) mRNA expressions in lung tissue, as well as lung and distal organ epithelial cell apoptosis were analyzed. RESULTS: We observed that: 1) hypervolemia increased lung W/D ratio with impairment of oxygenation and Est,L, and was associated with alveolar and endothelial cell damage and increased IL-6, VCAM-1, and ICAM-1 mRNA expressions; and 2) RM reduced alveolar collapse independent of volemic status. In hypervolemic animals, RM improved oxygenation above the levels observed with the use of positive-end expiratory pressure (PEEP), but increased lung injury and led to higher inflammatory and fibrogenetic responses. CONCLUSIONS: Volemic status should be taken into account during RMs, since in this sepsis-induced ALI model hypervolemia promoted and potentiated lung injury compared to hypo- and normovolemia.