Acute lung injury (ALI) is associated with det erioration of alveolar-capillary lining and transmigration and activation of inflammatory cells. Whereas a selective phosphodiesterase-4 (PDE4) inhibitor roflumilast has exerted potent anti-inflammatory properties, this study evaluated if its intravenous delivery can influence inflammation, edema formation, and respiratory parameters in rabbits with a lavage-induced model of ALI. ALI was induced by repetitive saline lung lavage (30 ml/kg). Animals were divided into 3 groups: ALI without therapy (ALI), ALI treated with roflumilast i.v. (1 mg/kg; ALI+Rofl), and healthy ventilated controls (Control), and were ventilated for following 4 h. Respiratory parameters (blood gases, ventilatory pressures, lung compliance, oxygenation indexes etc.) were measured and ca lculated regularly. At the end of experiment, animals were overdosed by anesthetics. Total and differential counts of cells in bronchoalveolar lavage fluid (BAL) were estimated microscopically. Lung edema was expressed as wet/dry lung weight ratio. Treatment with roflumilast reduced leak of cells (P<0.01), particularly of neutrophils (P<0.001), into the lung, decreased lung edema formation (P<0.01), and improved respiratory parameters. Concluding, the results indicate a future potential of PDE4 inhibitors also in the therapy of ALI., P. Kosutova, P. Mikolka, M. Kolomaznik, S. Rezakova, A. Calkovska, D. Mokra., and Obsahuje bibliografii
The aim of the study was to evaluate short-term heart rate variability (HRV) as an index of cardiac autonomic control in rats with lipopolysaccharide (LPS)-induced endotoxemia. Animals were injected intraperitoneally with LPS (100 μg/kg b.w.) and control group with an equivalent volume of saline. ECG recordings were done before (base) and 60, 120, 180, 240 and 300 min after LPS or saline administration. HRV magnitude was quantified by time and frequency-domain analysis (mean RR interval, SDRR, RMSSD, spectral powers in low (LF) and high frequency (HF) bands. Heart tissue homogenates and plasma were analyzed to determine interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and oxidative stress level (TBARS). Administration of lipopolysaccharide was followed by continuous rise in colonic body temperature compared to saline-treated controls. Endotoxemia in rats was accompanied by significant decrease in HRV spectral activity in high-frequency range at maximal body temperature (logHFpower: 1.2±0.5 vs. 1.9± 0.6 ms2, P<0.01). Increased IL-6 was found in heart tissue homogenates of LPS rats (8.0±0.6 vs. 26.4±4.8 pg/ml, (P<0.05). In conclusions, reduced HRV in HF band may indicate a decreased parasympathetic activity in LPS-induced endotoxemia as basic characteristics of altered cardiac control during response to endotoxemia., I. Zila, D. Mokra, J. Kopincova, M. Kolomaznik, M. Javorka, A. Calkovska., and Obsahuje bibliografii
Acute lung injury (ALI) is characterized by diffuse alveolar damage, inflammation, and transmigration and activation of inflammatory cells. This study evaluated if intravenous dexamethasone can influence lung inflammation and apoptosis in lavage-induced ALI. ALI was induced in rabbits by repetitive saline lung lavage (30ml/kg, 9±3-times). Animals were divided into 3 groups: ALI without therapy (ALI), ALI treated with
dexamethasone i.v. (0.5mg/kg, Dexamed; ALI+DEX), and healthy non-ventilated controls (Control). After following 5 h of ventilation, ALI animals were overdosed by anesthetics. Total and differential counts of cells in bronchoalveolar lavage fluid (BAL) were estimated. Lung edema was expressed as wet/dry weight ratio. Concentrations of IL-1ß, IL
-8, esRAGE, S1PR3 in the lung were analyzed by ELISA methods. In right lung, apoptotic cells were evaluated by TUNEL assay and caspase
-3 immunohistochemically. Dexamethasone showed a trend to improve lung functions and histopathological changes, reduced leak of neutrophils (P<0.001) into the lung, decreased concentrations of pro-inflammatory IL
-1β (P<0.05) and marker of lung injury esRAGE (P<0.05), lung edema formation (P<0.05), and lung apoptotic index (P<0.01), but increased
immunoreactivity of caspase-3 in the lung (P<0.001). Considering the action of dexamethasone on respiratory parameters and lung injury, the results indicate potential of this therapy in ALI.
The respiratory system is constantly exposed to pathogens which enter the lungs by inhalation or via blood stream. Lipopolysaccharide (LPS), also named endotoxin, can reach the airspaces as the major component of the outer membrane of Gram-negative bacteria, and lead to local inflammation and systemic toxicity. LPS affects alveolar type II (ATII) cells an d pulmonary surfactant and although surfactant molecule has the effective protective mechanisms, excessive amount of LPS interacts with surfactant film and leads to its inactivation. From immunological point of view, surfactant specific proteins (SPs) SP-A and SP-D are best characterized, however, there is increasing evidence on the involvement of SP-B and SP-C and certain phospholipids in immune reactions. In animal models, the instillation of LPS to the respiratory system induces acute lung injury (ALI). It is of clinical importance that endotoxin-induced lung injury can be favorably influenced by intratracheal instillation of exogenous surfactant. The beneficial effect of this treatment was confirmed for both natural porcine and synthetic surfactants. It is believed that the surfactant preparations have anti-inflammatory properties through regulating cytokine production by inflammatory cells. The mechanism by which LPS interferes with ATII cells and surfactant layer, and its consequences are discussed below., M. Kolomaznik, Z. Nova, A. Calkovska., and Obsahuje bibliografii
Damage of alveolar-capillary barrier, inflammation, oxidative
injury, and lung cell apoptosis represent the key features of acute
lung injury (ALI). This study evaluated if selective
phosphodiesterase (PDE)-4 inhibitor roflumilast can reduce the
mentioned changes in lavage-induced model of ALI. Rabbits with
ALI were divided into 2 groups: ALI without therapy (A group)
and ALI treated with roflumilast i.v. (1 mg/kg; A+R group). One
group of healthy animals without ALI served as ventilated
controls (C group). All animals were oxygen-ventilated for further
4 h. At the end of experiment, total and differential counts of
cells in bronchoalveolar lavage fluid (BALF) and total and
differential counts of white blood cells were estimated. Lung
edema formation was assessed from determination of protein
content in BALF. Pro-inflammatory cytokines (TNFα, IL-6 and
IL-8) and markers of oxidation (3-nitrotyrosine, thiobarbituricacid reactive substances) were detected in the lung tissue and
plasma. Apoptosis of lung cells was investigated
immunohistochemically. Treatment with roflumilast reduced leak
of cells, particularly of neutrophils, into the lung, decreased
concentrations of cytokines and oxidative products in the lung
and plasma, and reduced lung cell apoptosis and edema
formation. Concluding, PDE4 inhibitor roflumilast showed potent
anti-inflammatory actions in this model of ALI.
Meconium aspiration syndrome (MAS) in newborns is characterized mainly by respiratory failure due to surfactant dysfunction and inflammation. Previous meta-analyses did not prove any effect of exogenous surfactant treatment nor glucocorticoid administration on final outcome of children with MAS despite oxygenation improvement. As we supposed there is the need to intervene in both these fields simultaneously, we evaluated therapeutic effect of combination of exogenous surfactant and selective inhibitor of NF-κB (IKK-NBD peptide). Young New Zealand rabbits were instilled by meconium suspension and treated by surfactant alone or surfactant in combination with IKK-NBD, and oxygen-ventilated for 5 h. PaO2/FiO2, oxygenation index, oxygen saturation and ventilation efficiency index were evaluated every hour; post mortem, total and differential leukocyte counts were investigated in bronchoalveolar lavage fluid (BALF) and inflammatory, oxidative and apoptotic markers were assessed in lung tissue homogenates. Exogenous surfactant combined with IKK-NBD improved oxygenation, reduced neutrophil count in BALF and levels of IL-1β, IL-6, p38 MAPK and caspase 3 in comparison with surfactant-only therapy. It seems that inhibition of inflammation may be strong supporting factor in surfactant treatment of MAS., J. Kopincova, P. Mikolka, M. Kolomaznik, P. Kosutova, A. Calkovska, D. Mokra., and Obsahuje bibliografii
Inflammation and other immune responses are involved in the variety of diseases and disorders. The acute response to endotoxemia includes activation of innate immune mechanisms as well as changes in autonomic nervous activity. The autonomic nervous system and the inflammatory response are intimately linked and sympathetic and vagal nerves are thought to have anti-inflammation functions. The basic functional circuit between vagus nerve a nd inflammatory response was identified and the neuroimmunomodulation loop was called cholinergic anti-inflammatory pathway. Unique function of vagus nerve in the anti-inflammatory reflex arc was found in many experimental and pre-clinical studies. They br ought evidence on the cholinergic signaling interacting with systemic and local inflammation, particularly suppressing immune cells function. Pharmacological/electrical modulation of vagal activity suppressed TNF-α and other proinflammatory cytokines prod uction and had beneficial therapeutic effects. Many questions related to mapping, linking and targeting of vagal-immune interactions have been elucidated and brought understanding of its basic physiology and provided the initial support for development of Tracey's inflammatory reflex. This review summarizes and critically assesses the current knowledge defining cholinergic anti-inflammatory pathway with main focus on studies employing an experimental approach and emphasizes the potential of modulation of va gally-mediated anti-inflammatory pathway in the treatment strategies., I. Zila, D. Mokra, J. Kopincova, M. Kolomaznik, M. Javorka, A. Calkovska., and Obsahuje bibliografii