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228 Therapeutic Effect of Surfactant Inhalation on Lungs Donated after Cardiac Death in a Canine Lung Transplantation Model
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The Journal of Heart and Lung Transplantation, Vol 31, No 4S, April 2012
228
Conclusions: LPS preconditioning in lung ischemia reperfusion injury occurs via the TRAM dependent and therefore MyD88 independent pathway of the TLR-4 signaling complex. This finding has important implications for the development of IR prophylaxis without disruption of TLR-4’s ability to respond to infection.
Therapeutic Effect of Surfactant Inhalation on Lungs Donated after Cardiac Death in a Canine Lung Transplantation Model A. Ohsumi, F. Chen, J. Sakamoto, D. Nakajima, K. Hijiya, H. Motoyama, K. Okita, K. Horita, R. Kikuchi, T. Yamada, H. Sakai, T. Bando, H. Date. Thoracic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Purpose: In lung transplantation, donation after cardiac death (DCD) has been introduced worldwide. To date, several programs have reported acceptable outcomes; however, the number of patients on waiting lists is indeed much more than that of the donated organs. Therefore, we considered the effective use of marginal donor grafts from uncontrolled DCD donors by investigating the effect of surfactant inhalation against pulmonary ischemia-reperfusion injury in canine lungs from DCD donors. Methods and Materials: Donor dogs were rendered cardiac-dead and left at room temperature. Following cardiac arrest for 240 min, ventilation with 100% oxygen was performed for 60 min. The dogs were allocated into two groups: The NS group (n⫽7) received aerosolized normal saline and the SF group (n⫽5) received aerosolized surfactant during the 60 min of ventilation. Thereafter the recipient dogs underwent single left lung transplantation. The right main pulmonary artery was ligated at 45 min after reperfusion to evaluate the functions of the transplanted left lung for 240 min after the reperfusion. Results: In the NS group, two animals died of severe pulmonary edema at 75 min of reperfusion, while in the SF group, all 5 animals survived for 240 min after reperfusion. At the end of reperfusion, surfactant inhalation significantly increased dynamic compliance (p⬍0.001), oxygenation (p⬍0.01), and inhibited pulmonary edema (p⬍0.01). Surfactant inhalation effectively increased lung tissue levels of ATP and ADP (ATP, ADP: p⬍0.05), and also decreased IL-8 and TNF-alpha in bronchoalveolar lavage fluid (IL-8: p⬍0.01, TNF-alpha: p⬍0.05). Histologically, lungs in the SF group showed fewer signs of interstitial edema and hemorrhage, and less neutrophilic infiltration than those in the NS group. Conclusions: Our results confirmed that surfactant inhalation in the last phase of warm ischemia prevented ischemia-reperfusion injury. This method may contribute to improve the graft function from DCD donors and to expand the donor pool. 229 Lipopolysaccharide Preconditioning in Lung Ischemia-Reperfusion Injury Is TRAM Dependent P.J. Phelan, H.E. Merry, M.S. Mulligan. Division of Cardiothoracic Surgery, University of Washington, Seattle, WA. Purpose: Diverse preconditioning stimuli have been shown to confer protection from ischemia-reperfusion injury (IR). Previously, we have shown that LPS preconditioning is protective in a model of lung IR, but the mechanism remains undefined. TRAM, an adapter protein in the MyD88 independent TLR-4 pathway, has been implicated in both the late response to LPS and immuno-modulatory cytokine production. We hypothesize that LPS preconditioning occurs via TLR-4 in a TRAM dependent and therefore MyD88 independent fashion. Methods and Materials: Male Long-Evans rats were treated with vehicle or 20 nmol of TRAM siRNA prior to LPS preconditioning. TRAM knockdown was confirmed in BAL- isolated alveolar macrophages from treated animals. TRAM siRNA treated and control rats underwent intra-tracheal injection of either saline or low dose (15 ng/Kg) LPS. They subsequently underwent either thoracotomy alone or thoracotomy with temporary left hilar clamping, followed by reperfusion and re-ventilation. Pulmonary capillary permeability was measured by lung tissue BSA-I-125 accumulation at 4 hours of reperfusion. BAL performed at 4 hours or reperfusion was used for inflammatory cell count and cytokine ELISA quantification. SAPK phosphorylation was assessed by western blot after 15 minutes of reperfusion. Results: TRAM siRNA efficacy was confirmed with a ⬎90% TRAM reduction in alveolar macrophages. TRAM knockdown alone conferred neither protection nor augmentation of IR injury compared to IR controls. LPS preconditioning was protective with injury markers approaching the level of thoracotomy only controls. When TRAM was knocked down prior to LPS pre-treatment, protection was mitigated and lung injury markers returned to the level of IR controls.
230 Pharmacological Preconditioning of Lung with Monophosphoryl Lipid A: A Role of MyD88-Independent Signaling Pathway A. Shimamoto, H. Fujii, M. Tomita, Y. Yajima, M. Takao, H. Shimpo. Thoracic and Cardiovascular Surgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan. Purpose: We previously reported that the evidence for a protective role of the innate immune system in lung ischemic preconditioning (IPC), which is mediated a MyD88-independent pathway through TRIF, leading to NF-B activation and protection against lung ischemia-reperfusion (I/R) injury (LIRI). We therefore hypothesized that some of TLR4 ligands, which could selectively induce to TRIF, would provide pharmacological lung IPC. In the present study, we evaluated the effect of monophosphoryl lipid A (MPLA), a TRIF-based agonist of TLR4, on LIRI, especially whether MPLA affect pharmacological lung IPC through a MyD88-independent pathway to protect against LIRI. Methods and Materials: C57BL/6 mice received MPLA (500 g/kg) or vehicle 24 hours prior to 60 minutes of ischemia of their left lungs, followed by 180 minutes of reperfusion or IPC with six cycles of 5 minutes ischemia and 5 minutes reperfusion prior to I/R. Response to injury was quantified by tissue MPO activity, vascular permeability, and leukocyte and inflammatory mediator accumulation in BAL expression. Lung homogenates were also analyzed for activation of MyD88, TRIF, and NF-B. Results: Pretreatment of mice with MPLA resulted in the development of a significant smaller LIRI, which quantified by vascular permeability (P⫽.005), MPO activity (P⫽.001), and BAL components when compared with vehicle treated lungs. Instead of MyD88 activation, a strong activation of TRIF, leads to NF-B activation in MyD88-independent signaling pathway, is showing before I/R in the MPLA treated group same as conventional IPC group. Conclusions: We provide evidence for a protective role of the innate immune system in pharmacological lung IPC with MPLA. These data also indicate that IPC is mediated a MyD88-independent pathway, leading to NF-B activation and protection against LIRI. We conclude that an activation of TRIF, which are associate proteins of TLR4, would regulate a role of NF-B to preserve lung function. 231 Ventricular Assist Device Implantation in the Elderly: Nationwide Outcomes A. Kilic,1 D.D. Yuh,2 A.S. Shah,1 J.V. Conte.1 1Division of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, MD; 2Section of Cardiac Surgery, Yale University School of Medicine, New Haven, CT. Purpose: The aim of this study was to evaluate nationwide outcomes of ventricular assist device(VAD) implantation in the elderly. Methods and Materials: Elderly patients ⱖ70 years undergoing VAD implantation between 2003-2008 were identified in the weighted Nationwide Inpatient Sample. Costs of inpatient care, in-hospital outcomes, and home disposition rates were evaluated. Multivariable logistic regression analysis was conducted to evaluate the independent effect of age ⱖ70 years on in-hospital mortality. Results: A total of 542 patients ⱖ70 years were identified, representing 8.9% of all adult VAD implants during the study period. Mean age was 74.7 years, with 161(29.7%) females. Inpatient mortality occurred in 283(52.2%). After adjusting for significant patient, clinical, and hospital factors, age ⱖ70 years was not associated with an increased risk of in-hospital mortality compared to those aged 60-69.9 years(OR 1.33[0.742.41]; p⫽0.34). Average cost of inpatient care was $160,577. The discharge-to-home rate in survivors was 48.3%. Conclusions: This analysis demonstrates that approximately half of elderly patients ⱖ70 years undergoing VAD implantation survive to discharge, with half of survivors being able to be discharged home. Although age ⱖ70 years does not exert an independent effect on mortality compared to
The Journal of Heart and Lung Transplantation, Vol 31, No 4S, April 2012
228
Conclusions: LPS preconditioning in lung ischemia reperfusion injury occurs via the TRAM dependent and therefore MyD88 independent pathway of the TLR-4 signaling complex. This finding has important implications for the development of IR prophylaxis without disruption of TLR-4’s ability to respond to infection.
Therapeutic Effect of Surfactant Inhalation on Lungs Donated after Cardiac Death in a Canine Lung Transplantation Model A. Ohsumi, F. Chen, J. Sakamoto, D. Nakajima, K. Hijiya, H. Motoyama, K. Okita, K. Horita, R. Kikuchi, T. Yamada, H. Sakai, T. Bando, H. Date. Thoracic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Purpose: In lung transplantation, donation after cardiac death (DCD) has been introduced worldwide. To date, several programs have reported acceptable outcomes; however, the number of patients on waiting lists is indeed much more than that of the donated organs. Therefore, we considered the effective use of marginal donor grafts from uncontrolled DCD donors by investigating the effect of surfactant inhalation against pulmonary ischemia-reperfusion injury in canine lungs from DCD donors. Methods and Materials: Donor dogs were rendered cardiac-dead and left at room temperature. Following cardiac arrest for 240 min, ventilation with 100% oxygen was performed for 60 min. The dogs were allocated into two groups: The NS group (n⫽7) received aerosolized normal saline and the SF group (n⫽5) received aerosolized surfactant during the 60 min of ventilation. Thereafter the recipient dogs underwent single left lung transplantation. The right main pulmonary artery was ligated at 45 min after reperfusion to evaluate the functions of the transplanted left lung for 240 min after the reperfusion. Results: In the NS group, two animals died of severe pulmonary edema at 75 min of reperfusion, while in the SF group, all 5 animals survived for 240 min after reperfusion. At the end of reperfusion, surfactant inhalation significantly increased dynamic compliance (p⬍0.001), oxygenation (p⬍0.01), and inhibited pulmonary edema (p⬍0.01). Surfactant inhalation effectively increased lung tissue levels of ATP and ADP (ATP, ADP: p⬍0.05), and also decreased IL-8 and TNF-alpha in bronchoalveolar lavage fluid (IL-8: p⬍0.01, TNF-alpha: p⬍0.05). Histologically, lungs in the SF group showed fewer signs of interstitial edema and hemorrhage, and less neutrophilic infiltration than those in the NS group. Conclusions: Our results confirmed that surfactant inhalation in the last phase of warm ischemia prevented ischemia-reperfusion injury. This method may contribute to improve the graft function from DCD donors and to expand the donor pool. 229 Lipopolysaccharide Preconditioning in Lung Ischemia-Reperfusion Injury Is TRAM Dependent P.J. Phelan, H.E. Merry, M.S. Mulligan. Division of Cardiothoracic Surgery, University of Washington, Seattle, WA. Purpose: Diverse preconditioning stimuli have been shown to confer protection from ischemia-reperfusion injury (IR). Previously, we have shown that LPS preconditioning is protective in a model of lung IR, but the mechanism remains undefined. TRAM, an adapter protein in the MyD88 independent TLR-4 pathway, has been implicated in both the late response to LPS and immuno-modulatory cytokine production. We hypothesize that LPS preconditioning occurs via TLR-4 in a TRAM dependent and therefore MyD88 independent fashion. Methods and Materials: Male Long-Evans rats were treated with vehicle or 20 nmol of TRAM siRNA prior to LPS preconditioning. TRAM knockdown was confirmed in BAL- isolated alveolar macrophages from treated animals. TRAM siRNA treated and control rats underwent intra-tracheal injection of either saline or low dose (15 ng/Kg) LPS. They subsequently underwent either thoracotomy alone or thoracotomy with temporary left hilar clamping, followed by reperfusion and re-ventilation. Pulmonary capillary permeability was measured by lung tissue BSA-I-125 accumulation at 4 hours of reperfusion. BAL performed at 4 hours or reperfusion was used for inflammatory cell count and cytokine ELISA quantification. SAPK phosphorylation was assessed by western blot after 15 minutes of reperfusion. Results: TRAM siRNA efficacy was confirmed with a ⬎90% TRAM reduction in alveolar macrophages. TRAM knockdown alone conferred neither protection nor augmentation of IR injury compared to IR controls. LPS preconditioning was protective with injury markers approaching the level of thoracotomy only controls. When TRAM was knocked down prior to LPS pre-treatment, protection was mitigated and lung injury markers returned to the level of IR controls.
230 Pharmacological Preconditioning of Lung with Monophosphoryl Lipid A: A Role of MyD88-Independent Signaling Pathway A. Shimamoto, H. Fujii, M. Tomita, Y. Yajima, M. Takao, H. Shimpo. Thoracic and Cardiovascular Surgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan. Purpose: We previously reported that the evidence for a protective role of the innate immune system in lung ischemic preconditioning (IPC), which is mediated a MyD88-independent pathway through TRIF, leading to NF-B activation and protection against lung ischemia-reperfusion (I/R) injury (LIRI). We therefore hypothesized that some of TLR4 ligands, which could selectively induce to TRIF, would provide pharmacological lung IPC. In the present study, we evaluated the effect of monophosphoryl lipid A (MPLA), a TRIF-based agonist of TLR4, on LIRI, especially whether MPLA affect pharmacological lung IPC through a MyD88-independent pathway to protect against LIRI. Methods and Materials: C57BL/6 mice received MPLA (500 g/kg) or vehicle 24 hours prior to 60 minutes of ischemia of their left lungs, followed by 180 minutes of reperfusion or IPC with six cycles of 5 minutes ischemia and 5 minutes reperfusion prior to I/R. Response to injury was quantified by tissue MPO activity, vascular permeability, and leukocyte and inflammatory mediator accumulation in BAL expression. Lung homogenates were also analyzed for activation of MyD88, TRIF, and NF-B. Results: Pretreatment of mice with MPLA resulted in the development of a significant smaller LIRI, which quantified by vascular permeability (P⫽.005), MPO activity (P⫽.001), and BAL components when compared with vehicle treated lungs. Instead of MyD88 activation, a strong activation of TRIF, leads to NF-B activation in MyD88-independent signaling pathway, is showing before I/R in the MPLA treated group same as conventional IPC group. Conclusions: We provide evidence for a protective role of the innate immune system in pharmacological lung IPC with MPLA. These data also indicate that IPC is mediated a MyD88-independent pathway, leading to NF-B activation and protection against LIRI. We conclude that an activation of TRIF, which are associate proteins of TLR4, would regulate a role of NF-B to preserve lung function. 231 Ventricular Assist Device Implantation in the Elderly: Nationwide Outcomes A. Kilic,1 D.D. Yuh,2 A.S. Shah,1 J.V. Conte.1 1Division of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, MD; 2Section of Cardiac Surgery, Yale University School of Medicine, New Haven, CT. Purpose: The aim of this study was to evaluate nationwide outcomes of ventricular assist device(VAD) implantation in the elderly. Methods and Materials: Elderly patients ⱖ70 years undergoing VAD implantation between 2003-2008 were identified in the weighted Nationwide Inpatient Sample. Costs of inpatient care, in-hospital outcomes, and home disposition rates were evaluated. Multivariable logistic regression analysis was conducted to evaluate the independent effect of age ⱖ70 years on in-hospital mortality. Results: A total of 542 patients ⱖ70 years were identified, representing 8.9% of all adult VAD implants during the study period. Mean age was 74.7 years, with 161(29.7%) females. Inpatient mortality occurred in 283(52.2%). After adjusting for significant patient, clinical, and hospital factors, age ⱖ70 years was not associated with an increased risk of in-hospital mortality compared to those aged 60-69.9 years(OR 1.33[0.742.41]; p⫽0.34). Average cost of inpatient care was $160,577. The discharge-to-home rate in survivors was 48.3%. Conclusions: This analysis demonstrates that approximately half of elderly patients ⱖ70 years undergoing VAD implantation survive to discharge, with half of survivors being able to be discharged home. Although age ⱖ70 years does not exert an independent effect on mortality compared to