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The role of myeloperoxidase in hyperoxia-induced bronchopulmonary dysplasia
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A. Newman / Free Radical Biology and Medicine 128 (2018) S21–S46
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S-glutathionylation of pyruvate kinase M2 is associated with metabolic reprogramming and cytokine production in the development of allergic obese airway disease Allison Manuel 1, n, Xi Qian 2, Reem Aboushousha 1, Cheryl van de Wetering 1, Shi Biao Chia 1, Ying-Wai Lam 1, Jos van der Velden 1, Albert van der Vliet 1, Anne Dixon 1, Matthew Poynter 1, Charles Irvin 1, Yvonne Janssen-Heininger 1 1 2
University of Vermont, USA Tufts University, USA
Early on-set allergic obese asthma is an important global clinical problem due to the mounting number of patients and their disease severity that is poorly controlled with available therapeutics. Alterations in metabolism and accompanying changes in redox homeostasis are known to contribute to obesity-associated diseases. Protein S-glutathionylation (PSSG) is a redox-based modification of protein cysteines involving the conjugation of glutathione to the reactive thiol group. We have discovered a direct correlation between PSSG chemistry, glycolysis and inflammation in the lungs from mice fed a high fat diet for 15 weeks. Analysis of lung tissue from obese mice identified that the glycolytic enzyme pyruvate kinase M2 (PKM2), known to catalyze the final step in glycolysis, is a target of s-glutathionylation in the lung tissue from obese mice. Furthermore, we have identified that oxidative stress and s-glutathionylation of PKM2 are increased in primary tracheal epithelial cells cultured in high glucose (25 mM) and treated with palmitate compared to MTECs cultured in normal glucose (5.6 mM). The objective of this study was to identify the s-glutathionylated proteome and investigate if s-glutathionylation of PKM2 alters its protein function to enhance inflammation in the lung tissue from mice treated with house dust mite and subjected to diet induced obesity, a model of early on-set allergic obese asthma. Here we show that s-glutathionylation of PKM2 decreases its glycolytic enzyme activity. This correlates with the upregulation of the inflammatory cytokines thymic stromal lymphopoietin (TSLP) and granulocyte-macrophage colony-stimulating factor (GM-CSF), known to contribute to steroid resistance and neutrophil infiltration in the lung during obesity. Treatment of primary mouse tracheal epithelial cells with the PKM2 small molecule activator TEPP46 attenuates mRNA expression and secretion of TSLP and GM-CSF. Overall, these findings suggest that unique redox perturbations and glycolysis may contribute to the enigmatic endotype of allergic obese asthma.
https://doi.org/10.1016/j.freeradbiomed.2018.10.035
34
The role of myeloperoxidase in hyperoxia-induced bronchopulmonary dysplasia Ru-Jeng Teng 1, Xigang Jing 1, Ganesh Konduri 1, Dustin Martin 1, n, Stephen Naylor 2, Kirkwood Pritchard 1 1 2
Medical College of Wisconsin, USA ReNeuroGen, LLC., USA
Bronchopulmonary dysplasia (BPD) is the most common chronic pulmonary disease of premature neonates. While ventilation with supplemental O2 is required for development and survival of the premature neonate, it increases the risk of BPD. Both hyperoxia-induced oxidative
stress and transient hypoxia resulting from apneic events increase recruitment and activation of myeloid cells to the lungs. Activated myeloid cells release myeloperoxidase (MPO), which oxidizes chloride ions to hypochlorous acid causing oxidative damage and cell death. If myeloid cell recruitment, activation, and MPO release contribute to the pathogenesis of BPD, then inhibiting MPO oxidant production should protect against hyperoxia-induced lung injury. N-acetyl lysyltyrosylcysteine amide (KYC) is a tripeptide inhibitor of MPO that prevents the generation of toxic oxidants by shuttling high energy peroxy radicals in the iron-heme active site into the glutathione pathway. In order to test the hypothesis that inhibiting MPO prevents hyperoxia-induced lung damage, Sprague-Dawley neonatal rat pups were exposed to ten days (P1-P10) of hyperoxia (4 90% O2) and injected twice daily with either 5 mg/kg KYC or vehicle control (PBS). KYC treatment reduced myeloid cell counts and MPO and Cl-Tyr levels in the lungs of hyperoxic neonatal pups. Additionally, KYCtreated pups had increased microvascular and alveolar complexity as well as nuclear factor (erythroid-derived 2)-like 2 (Nrf2) levels. These data provide evidence that myeloid cell recruitment and activation and MPO-induced oxidative damage are significant contributors to hyperoxiainduced lung injury in the developing lungs, and that KYC is an effective inhibitor of MPO-dependent oxidative damage to neonatal lungs.
https://doi.org/10.1016/j.freeradbiomed.2018.10.036
35
Neutrophils in sickle cell disease: the missing candidate – myeloperoxidase Dustin Martin 1, n, Guoliang Yu 1, Ye Liang 2, Cheryl Hillery 3, Stephen Naylor 4, Kirkwood Pritchard 1 1
Medical College of Wisconsin, USA Johns Hopkins University, USA 3 University of Pittsburgh, USA 4 ReNeuroGen, LLC., USA 2
Sickle cell disease (SCD) is caused by a single point mutation of the βglobin gene that increases the polymerization of hemoglobin under hypoxia and subsequent sickling of red blood cells (RBCs). Sickled RBCs occlude capillaries, inducing ischemic attacks in the lungs of affected individuals. Increased hemolysis and repeated bouts of ischemia-reperfusion injury lead to chronic states of oxidative stress and inflammation. Previously, we reported that sickle disease increases neutrophil activation and release of myeloperoxidase (MPO), which generates toxic oxidants that impair vascular function in SCD mice. In the present study, we determine if N-acetyl lysyltyrosylcysteine amide (KYC), a tripeptide inhibitor of MPO prevents toxic oxidant production and oxidative damage to sickle RBCs in SCD mice. KYC treatment of SCD mice reduced NO2-Tyr and Cl-Tyr, both markers of MPO-mediated damage, on sickle RBC membranes. Interestingly, the number of sickled RBCs in the lungs in KYC-treated SCD mice were reduced, which correlated with a reduction in the number of occluded blood vessels in the lungs of perfused SCD mice. KYC treatment also reduced MPO deposition, Cl-Tyr formation, and IgG deposition in the interstitium of the lungs of SCD mice. These data indicate KYC reduces oxidative damage to sickle RBCs which decreases sickling, vaso-occlusion, and ischemic injury of the lungs in sickle animals. KYC-dependent reductions in MPO-dependent oxidative damage to the lungs correlated with decreased vascular leakage in the lungs of SCD mice and reductions in SCD-related lung pathology. In conclusion, inhibitors that target MPO, such as KYC, may be an effective strategy for reducing vaso-occlusive events in SCD.
https://doi.org/10.1016/j.freeradbiomed.2018.10.037
A. Newman / Free Radical Biology and Medicine 128 (2018) S21–S46
33
S-glutathionylation of pyruvate kinase M2 is associated with metabolic reprogramming and cytokine production in the development of allergic obese airway disease Allison Manuel 1, n, Xi Qian 2, Reem Aboushousha 1, Cheryl van de Wetering 1, Shi Biao Chia 1, Ying-Wai Lam 1, Jos van der Velden 1, Albert van der Vliet 1, Anne Dixon 1, Matthew Poynter 1, Charles Irvin 1, Yvonne Janssen-Heininger 1 1 2
University of Vermont, USA Tufts University, USA
Early on-set allergic obese asthma is an important global clinical problem due to the mounting number of patients and their disease severity that is poorly controlled with available therapeutics. Alterations in metabolism and accompanying changes in redox homeostasis are known to contribute to obesity-associated diseases. Protein S-glutathionylation (PSSG) is a redox-based modification of protein cysteines involving the conjugation of glutathione to the reactive thiol group. We have discovered a direct correlation between PSSG chemistry, glycolysis and inflammation in the lungs from mice fed a high fat diet for 15 weeks. Analysis of lung tissue from obese mice identified that the glycolytic enzyme pyruvate kinase M2 (PKM2), known to catalyze the final step in glycolysis, is a target of s-glutathionylation in the lung tissue from obese mice. Furthermore, we have identified that oxidative stress and s-glutathionylation of PKM2 are increased in primary tracheal epithelial cells cultured in high glucose (25 mM) and treated with palmitate compared to MTECs cultured in normal glucose (5.6 mM). The objective of this study was to identify the s-glutathionylated proteome and investigate if s-glutathionylation of PKM2 alters its protein function to enhance inflammation in the lung tissue from mice treated with house dust mite and subjected to diet induced obesity, a model of early on-set allergic obese asthma. Here we show that s-glutathionylation of PKM2 decreases its glycolytic enzyme activity. This correlates with the upregulation of the inflammatory cytokines thymic stromal lymphopoietin (TSLP) and granulocyte-macrophage colony-stimulating factor (GM-CSF), known to contribute to steroid resistance and neutrophil infiltration in the lung during obesity. Treatment of primary mouse tracheal epithelial cells with the PKM2 small molecule activator TEPP46 attenuates mRNA expression and secretion of TSLP and GM-CSF. Overall, these findings suggest that unique redox perturbations and glycolysis may contribute to the enigmatic endotype of allergic obese asthma.
https://doi.org/10.1016/j.freeradbiomed.2018.10.035
34
The role of myeloperoxidase in hyperoxia-induced bronchopulmonary dysplasia Ru-Jeng Teng 1, Xigang Jing 1, Ganesh Konduri 1, Dustin Martin 1, n, Stephen Naylor 2, Kirkwood Pritchard 1 1 2
Medical College of Wisconsin, USA ReNeuroGen, LLC., USA
Bronchopulmonary dysplasia (BPD) is the most common chronic pulmonary disease of premature neonates. While ventilation with supplemental O2 is required for development and survival of the premature neonate, it increases the risk of BPD. Both hyperoxia-induced oxidative
stress and transient hypoxia resulting from apneic events increase recruitment and activation of myeloid cells to the lungs. Activated myeloid cells release myeloperoxidase (MPO), which oxidizes chloride ions to hypochlorous acid causing oxidative damage and cell death. If myeloid cell recruitment, activation, and MPO release contribute to the pathogenesis of BPD, then inhibiting MPO oxidant production should protect against hyperoxia-induced lung injury. N-acetyl lysyltyrosylcysteine amide (KYC) is a tripeptide inhibitor of MPO that prevents the generation of toxic oxidants by shuttling high energy peroxy radicals in the iron-heme active site into the glutathione pathway. In order to test the hypothesis that inhibiting MPO prevents hyperoxia-induced lung damage, Sprague-Dawley neonatal rat pups were exposed to ten days (P1-P10) of hyperoxia (4 90% O2) and injected twice daily with either 5 mg/kg KYC or vehicle control (PBS). KYC treatment reduced myeloid cell counts and MPO and Cl-Tyr levels in the lungs of hyperoxic neonatal pups. Additionally, KYCtreated pups had increased microvascular and alveolar complexity as well as nuclear factor (erythroid-derived 2)-like 2 (Nrf2) levels. These data provide evidence that myeloid cell recruitment and activation and MPO-induced oxidative damage are significant contributors to hyperoxiainduced lung injury in the developing lungs, and that KYC is an effective inhibitor of MPO-dependent oxidative damage to neonatal lungs.
https://doi.org/10.1016/j.freeradbiomed.2018.10.036
35
Neutrophils in sickle cell disease: the missing candidate – myeloperoxidase Dustin Martin 1, n, Guoliang Yu 1, Ye Liang 2, Cheryl Hillery 3, Stephen Naylor 4, Kirkwood Pritchard 1 1
Medical College of Wisconsin, USA Johns Hopkins University, USA 3 University of Pittsburgh, USA 4 ReNeuroGen, LLC., USA 2
Sickle cell disease (SCD) is caused by a single point mutation of the βglobin gene that increases the polymerization of hemoglobin under hypoxia and subsequent sickling of red blood cells (RBCs). Sickled RBCs occlude capillaries, inducing ischemic attacks in the lungs of affected individuals. Increased hemolysis and repeated bouts of ischemia-reperfusion injury lead to chronic states of oxidative stress and inflammation. Previously, we reported that sickle disease increases neutrophil activation and release of myeloperoxidase (MPO), which generates toxic oxidants that impair vascular function in SCD mice. In the present study, we determine if N-acetyl lysyltyrosylcysteine amide (KYC), a tripeptide inhibitor of MPO prevents toxic oxidant production and oxidative damage to sickle RBCs in SCD mice. KYC treatment of SCD mice reduced NO2-Tyr and Cl-Tyr, both markers of MPO-mediated damage, on sickle RBC membranes. Interestingly, the number of sickled RBCs in the lungs in KYC-treated SCD mice were reduced, which correlated with a reduction in the number of occluded blood vessels in the lungs of perfused SCD mice. KYC treatment also reduced MPO deposition, Cl-Tyr formation, and IgG deposition in the interstitium of the lungs of SCD mice. These data indicate KYC reduces oxidative damage to sickle RBCs which decreases sickling, vaso-occlusion, and ischemic injury of the lungs in sickle animals. KYC-dependent reductions in MPO-dependent oxidative damage to the lungs correlated with decreased vascular leakage in the lungs of SCD mice and reductions in SCD-related lung pathology. In conclusion, inhibitors that target MPO, such as KYC, may be an effective strategy for reducing vaso-occlusive events in SCD.
https://doi.org/10.1016/j.freeradbiomed.2018.10.037