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Depto. de FisiologíaFac. de MedicinaFALSEsubmitte

Ischaemic preconditioning prevents the liver inflammatory response to lung ischaemia/reperfusion in a swine lung autotransplant model†

OBJECTIVES: Lung ischaemia/reperfusion (IR) induces a systemic inflammatory response that causes damage to remote organs. The liver is particularly sensitive to circulating inflammatory mediators that occur after IR of remote organs. Recently, remote ischaemic preconditioning has been proposed as a surgical tool to protect several organs from IR. The present study was designed to investigate a possible protective effect of lung ischaemic preconditioning (IP) against the liver inflammatory response to lung IR. METHODS: Two groups [IP and control (CON)] of 10 Large White pigs underwent lung autotransplants (left pneumonectomy, ex situ cranial lobectomy and caudal lobe reimplantation). Before pneumonectomy was performed in the study group, IP was induced with two 5-min cycles of left pulmonary arterial occlusion and a 5-min interval of reperfusion between the two occlusions. Five animals underwent sham surgery. Liver biopsies were obtained during surgery at (i) prepneumonectomy, (ii) prereperfusion, (iii) 10 min after reperfusion of the implanted lobe and (iv) 30 min after reperfusion. The expression of tumor necrosis factor-α (TNF-α), interleukin (IL)- 1, IL-10 and inducible form of nitric oxide synthase (iNOS) was analysed by western blotting. The expression of mRNA for TNF-α, IL1, IL-10, monocyte chemoattractant protein-1 (MCP-1), nuclear factor kappa beta and iNOS was analysed by reverse transcription–polymerase chain reaction. Caspase-3 activity was determined by enzyme-linked immunosorbent assay. Non-parametric tests were used to compare differences between and within groups. RESULTS: Lung IR markedly increased expression of TNF-α (P = 0.0051) and IL-1 (P = 0.0051) and caspase-3 activity (P = 0.0043) in the CON group compared with the prepneumonectomy levels. A decrease of IL-10 mRNA expression was observed in the CON group after lung reperfusion. In the IP group, TNF-α (P = 0.0011) and IL-1 (P = 0.0001) expression and caspase-3 activity (P < 0.0009) were lower after reperfusion than in the CON group. IP caused reversion of the observed decrease of IL-10 mRNA expression (P = 0.016) induced in liver tissue by lung IR. Lung IR markedly increased the expression of mRNA MCP-1 after 10 min (P = 0.0051) and 30 min (P = 0.0051) of reperfusion. These increases were not observed in the IP or sham groups. CONCLUSIONS: IP prevented liver injury induced by lung IR through the reduction of proinflammatory cytokines and hepatocyte apoptosis.Depto. de Bioquímica y Biología MolecularFac. de MedicinaTRUEpu

Modulation of monocyte chemoattractant protein-1 expression by ischaemic preconditioning in a lung autotransplant model

Objectives: Monocyte chemoattractant protein-1 (MCP-1) is believed to play a crucial role in lung ischaemia-reperfusion injury (LIRI). Ischaemic preconditioning (IP) has been shown to protect several organs from ischaemia-reperfusion (IR) injury, although less is known about IP's effect on MCP-1 modulation. The objective of this study was to investigate IP's effect on MCP-1 expression in lung tissue and its relationship with oxidative stress and proinflammatory cytokine production in an experimental LIRI model. Methods: Two groups (IP and control groups) of seven large white pigs underwent a lung autotransplant (left pneumonectomy, ex situ superior lobectomy and lower lobe reimplantation). Before pneumonectomy was performed in the study group, IP was induced with two cycles of 5 min of left pulmonary artery occlusion with a 5 min interval of reperfusion between the two occlusions. Blood samples and lung biopsies were obtained at prepneumonectomy (PPn), at prereperfusion (PRp) and up to 30 min after reperfusion of the implanted lobe (Rp-10' and Rp-30'). Haemodynamic and blood-gas measurements, evaluation of oxidative stress in lung tissue and MCP-1, tumour necrosis factor-α (TNF-α) and IL-1 protein and mRNA measurements in lung tissue were performed. Nonparametric tests were used to compare differences between groups. Data are expressed as mean ± SEM. Results: In control lungs, MCP-1 protein levels were found to be higher at PRp, Rp-10' and Rp-30' than at PPn (0.59 ± 0.1 vs. 0.21 ± 0.05, 0.47 ± 0.01 vs. 0.21 ± 0.05 and 0.56 ± 0.01 vs. 0.21 ± 0.05, respectively; P < 0.05). These differences were not evident in the IP group. MCP-1 levels at PRp, Rp-10' and Rp-30' were significantly higher in the control group than in the IP group (0.59 ± 0.1 vs. 0.15 ± 0.02, 0.47 ± 0.01 vs. 0.13 ± 0.01 and 0.56 ± 0.01 vs. 0.27 ± 0.01, respectively; P < 0.05). MCP-1, TNF-α and IL-1 mRNA expressions were lower at PRp, Rp-10' and Rp-30' (control vs. IP group, P < 0.05) when IP was carried out. Lipid peroxidation metabolites and myeloperoxidase activity increase in lung tissue were prevented by IP. Conclusions: In this model, LIRI induced the expression of MCP-1 and the proinflammatory proteins TNF-α and IL-1 in control lungs. IP significantly reduced the expression of these chemokines and cytokines. These features may explain the reduction of oxidative stress observed with IP.Instituto Salud Carlos IIISociedad Española de Neuomologia y Cirugía ToracicaDepto. de Farmacología y ToxicologíaFac. de MedicinaTRUEpu

Thoracic paravertebral block after thoracotomy: comparison of three different approaches

Background: Thoracic paravertebral block (TPVB) is a regional block technique increasingly used for the early management of post-thoracotomy pain. We compare three different postoperative analgesic approaches based on TPVB: anesthetist, anesthetist plus surgeon, and surgeon. Materials and methods: We randomized 54 patients undergoing elective thoracotomy to three different postoperative analgesia groups: paravertebral percutaneous catheter (PVA group), paravertebral percutaneous catheter plus incisional (subcutaneous) catheter (PVA+Inc), and paravertebral catheter under direct vision (PVS group). During early postoperative 48h, we measured pain intensity, intravenous morphine afforded by the patient-controlled analgesia pump, and the spirometric test. Results: There were no statistically significant differences among the collected preoperative data. No significant differences were observed on postoperative spirometric values. Analgesic quality was better in PVA+Inc group at 12 and 24 postoperative hours. In this group, intravenous morphine use to improve analgesia was significantly lower from 8h until 48h postoperative. Conclusions: Association of thoracic paravertebral block to continuous infusion of a local anesthetic in the surgical incision area affords a better pain relief than paravertebral block alone (introduced by the surgeon or the anesthetist).Depto. de Farmacología y ToxicologíaFac. de MedicinaTRUEpu

The effects of anesthetic preconditioning with sevoflurane in an experimental lung autotransplant model in pigs

Background: Ischemia-reperfusion lung injury is doubly important in thoracic surgery because of the associated ventilation damage to 1 lung. In this study we evaluated the cytoprotective effects of sevoflurane in a pulmonary autotransplant model in pigs. Methods: Twenty Large White pigs undergoing pneumonectomy plus lung autotransplant were divided into 2 10-member groups on the basis of the anesthetic received (propofol or sevoflurane). Proinflammatory mediators, oxidative stress, nitric oxide metabolism, and hemodynamic and blood variables were measured at 5 different time points. Results: There was an increase of oxidative stress markers and proinflammatory mediators in the propofol group, whereas the hemodynamic variables were similar in both groups. Conclusions: We demonstrated that sevoflurane decreased the inflammatory response and oxidative stress in a live ischemia-reperfusion lung model.Instituto de Salud Carlos IIILABORATORIOS ABBOTSOCIEDAD ESPAÑOLA NEUMOLOGÍA Y CIRUGÍA TORÁCICADepto. de Farmacología y ToxicologíaFac. de MedicinaTRUEpu

Effects of Intraoperative Infusion of Esmolol on Systemic and Pulmonary Inflammation in a Porcine Experimental Model of Lung Resection Surgery

Abstract BACKGROUND: Lung resection surgery (LRS) is associated with systemic and pulmonary inflammation, which can affect postoperative outcomes. Activation of β-adrenergic receptors increases the expression of proinflammatory and anti-inflammatory mediators, and their blockade may attenuate the systemic inflammatory response. The aim of this study was to analyze the effect of a continuous perioperative intravenous perfusion of esmolol on postoperative pulmonary edema in an experimental model of LRS requiring periods of one-lung ventilation (OLV). METHODS: Twenty-four large white pigs were randomly assigned to 3 groups: control (CON), esmolol (ESM), and sham. The ESM group received an intravenous esmolol bolus (0.5 mg/kg) and then an esmolol infusion (0.05 mg·kg−1·minute−1) throughout the procedure. The CON group received the same volume of 0.9% saline solution as the ESM group plus a continual infusion of saline. The sham group underwent a left thoracotomy without LRS or OLV. At the end of the LRS, the animals were awakened, and after 24 hours, they underwent general anesthesia again. Lung biopsies and plasma samples were obtained to analyze the levels and expression of inflammatory mediators, and the animals also received a bronchoalveolar lavage. RESULTS: At 24 hours after the operation, the ESM group had less lung edema and lower expression of the proinflammatory biomarkers tumor necrosis factor (TNF) and interleukin (IL)-1 compared to the CON group for both lung lobes. For the mediastinal lobe biopsies, the mean difference and 95% confidence interval (CI) between the groups for edema, TNF, and IL-1 were 14.3 (95% CI, 5.6–23.1), P = .002; 0.19 (95% CI, 0.07–0.32), P = .002; and 0.13 (95% CI, 0.04–0.22), P = .006, respectively. In the left upper lobe, the mean differences for edema, TNF, and IL-1 were 12.4 (95% CI, 4.2–20.6), P = .003; 0.25 (95% CI, 0.12–0.37), P < .001; and 0.3 (95% CI, 0.08–0.53), P = .009. CONCLUSIONS: Our results suggest that esmolol reduces lung edema and inflammatory responses in the intraoperative and postoperative periods in animals that underwent LRS with OLV.Depto. de Bioquímica y Biología MolecularFac. de MedicinaTRUEpu

Sevoflurane prevents liver inflammatory response induced by lung ischemia-reperfusion.

Background: Transplants cause ischemia-reperfusion (IR) injury that can affect distant organs. Liver is particularly sensitive to IR injury. The present randomized experimental study was designed to investigate a possible protective effect of sevoflurane against liver inflammatory response to lung IR in a lung upper lobe left autotransplant model. Methods: Two groups (sevoflurane and control) of eight swines each were submitted to upper lobe left lung autotransplant. Hypnotic maintenance was performed with sevoflurane 3% or propofol 8 to 10 mg/kg per hr until pneumonectomy was done; then propofol was used for all animals. Blood and liver samples were taken in four different moments: prepneumonectomy, prereperfusion, 10 min postreperfusion and 30 min postreperfusion to measure levels of interleukin (IL)-1β, IL-10, tumor necrosis factor (TNF)-α, monocyte chemotactic protein (MCP)-1, nuclear factor (NF)-κB, C-reactive protein, ferritin and caspase 3. Non-parametric test was used to find statistical meaning. Results: Lung IR markedly increased the expression of TNF-α, IL-1β, MCP-1, NF-κB and caspase activity in control livers compared with basal levels, whereas liver IL-10 expression decreased 10 and 30 min post-reperfusion. Sevoflurane significantly decreased TNF-α, IL-1β, MCP-1, NF-κB liver expression and caspase 3 activity. Sevoflurane also reverted the lung IR-induced decrease in IL-10 expression. Conclusions: The present results indicate that lung IR caused hepatic injury. Sevoflurane attenuated liver injury in a model of upper lobe left lung autotransplant in pigs.Rodriguez Pascual FoundationINSTITUTO SALUD CARLOS IIISociedad Madrileña de Neumología y Cirugía TorácicaDepto. de Farmacología y ToxicologíaFac. de MedicinaTRUEpu

Sevoflurane Prevents Liver Inflammatory Response Induced by Lung Ischemia-Reperfusion

Background: Transplants cause ischemia-reperfusion (IR) injury that can affect distant organs. Liver is particularly sensitive to IR injury. The present randomized experimental study was designed to investigate a possible protective effect of sevoflurane against liver inflammatory response to lung IR in a lung upper lobe left autotransplant model. Methods: Two groups (sevoflurane and control) of eight swines each were submitted to upper lobe left lung autotransplant. Hypnotic maintenance was performed with sevoflurane 3% or propofol 8 to 10 mg/kg per hr until pneumonectomy was done; then propofol was used for all animals. Blood and liver samples were taken in four different moments: prepneumonectomy, prereperfusion, 10 min postreperfusion and 30 min postreperfusion to measure levels of interleukin (IL)-1β, IL-10, tumor necrosis factor (TNF)-α, monocyte chemotactic protein (MCP)-1, nuclear factor (NF)-κB, C-reactive protein, ferritin and caspase 3. Non-parametric test was used to find statistical meaning. Results: Lung IR markedly increased the expression of TNF-α, IL-1β, MCP-1, NF-κB and caspase activity in control livers compared with basal levels, whereas liver IL-10 expression decreased 10 and 30 min post-reperfusion. Sevoflurane significantly decreased TNF-α, IL-1β, MCP-1, NF-κB liver expression and caspase 3 activity. Sevoflurane also reverted the lung IR-induced decrease in IL-10 expression. Conclusions: The present results indicate that lung IR caused hepatic injury. Sevoflurane attenuated liver injury in a model of upper lobe left lung autotransplant in pigs.Ministerio de Ciencia y Educación (España)Depto. de Bioquímica y Biología MolecularFac. de MedicinaTRUEpu

Lidocaine Administration Controls MicroRNAs Alterations Observed After Lung Ischemia–Reperfusion Injury

BACKGROUND: Ischemia–reperfusion injury (IRI) is associated with morbidity and mortality. MicroRNAs (miRNAs) have emerged as regulators of IRI, and they are involved in the pathogenesis of organ rejection. Lidocaine has proven anti-inflammatory activity in several tissues but its modulation of miRNAs has not been investigated. This work aims to investigate the involvement of miRNAs in lung IRI in a lung auto-transplantation model and to investigate the effect of lidocaine. METHODS: Three groups (sham, control, and Lidocaine), each comprising 6 pigs, underwent a lung autotransplantation. All groups received the same anesthesia. In addition, animals of lidocaine group received a continuous intravenous administration of lidocaine (1.5 mg/kg/h) during surgery. Lung biopsies were taken before pulmonary artery clamp, before reperfusion, 30 minutes postreperfusion (Rp-30), and 60 minutes postreperfusion (Rp-60). Samples were analyzed for different miRNAs (miR-122, miR-145, miR-146a, miR-182, miR-107, miR-192, miR-16, miR-21, miR-126, miR-127, miR142-5p, miR152, miR155, miR-223, and let7) via the use of reverse-transcription quantitative polymerase chain reaction. Results were normalized with miR-103. RESULTS: The expression of miR-127 and miR-16 did not increase after IRI. Let-7d, miR-21, miR-107, miR-126, miR-145, miR-146a, miR-182, and miR-192 significantly increased at the Rp-60 (control versus sham P < .001). miR-142-5p, miR-152, miR-155, and miR 223 significantly increased at the Rp-30 (control versus sham P < .001) and at the Rp-60 (control versus. sham P < .001). The administration of lidocaine was able to attenuate these alterations in a significant way (control versus Lidocaine P < .001). CONCLUSIONS: Lung IRI caused dysregulation miRNA. The administration of lidocaine reduced significantly miRNAs alterations.Depto. de Bioquímica y Biología MolecularFac. de MedicinaTRUEpu