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Correale M, Tricarico L, Bevere EML, Chirivì F, Croella F, Severino P, Mercurio V, Magrì D, Dini F, Licordari R, Beltrami M, Dattilo G, Salzano A, Palazzuoli A. Circulating Biomarkers in Pulmonary Arterial Hypertension: An Update. Biomolecules 2024; 14:552. [PMID: 38785959 PMCID: PMC11117582 DOI: 10.3390/biom14050552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 04/25/2024] [Accepted: 05/01/2024] [Indexed: 05/25/2024] Open
Abstract
Pulmonary arterial hypertension (PAH) is a rare subtype of group 1 pulmonary hypertension (PH) diseases, characterized by high pulmonary artery pressure leading to right ventricular dysfunction and potential life-threatening consequences. PAH involves complex mechanisms: vasoconstriction, vascular remodeling, endothelial dysfunction, inflammation, oxidative stress, fibrosis, RV remodeling, cellular hypoxia, metabolic imbalance, and thrombosis. These mechanisms are mediated by several pathways, involving molecules like nitric oxide and prostacyclin. PAH diagnosis requires clinical evaluation and right heart catheterization, confirming a value of mPAP ≥ 20 mmHg at rest and often elevated pulmonary vascular resistance (PVR). Even if an early and accurate diagnosis is crucial, PAH still lacks effective biomarkers to assist in its diagnosis and prognosis. Biomarkers could contribute to arousing clinical suspicion and serve for prognosis prediction, risk stratification, and dynamic monitoring in patients with PAH. The aim of the present review is to report the main novelties on new possible biomarkers for the diagnosis, prognosis, and treatment monitoring of PAH.
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Affiliation(s)
- Michele Correale
- Cardiothoracic Department, Ospedali Riuniti University Hospital, 71100 Foggia, Italy
| | - Lucia Tricarico
- Department of Medical and Surgical Sciences, University of Foggia, 71100 Foggia, Italy; (L.T.); (E.M.L.B.); (F.C.)
| | - Ester Maria Lucia Bevere
- Department of Medical and Surgical Sciences, University of Foggia, 71100 Foggia, Italy; (L.T.); (E.M.L.B.); (F.C.)
| | - Francesco Chirivì
- Department of Medical and Surgical Sciences, University of Foggia, 71100 Foggia, Italy; (L.T.); (E.M.L.B.); (F.C.)
| | - Francesca Croella
- Cardiothoracic Vascular Department, Division of Provincial Cardiology, Santissima Annunziata Hospital and Delta Hospital, Azienda Unità Sanitaria Locale di Ferrara, 44121 Ferrara, Italy;
| | - Paolo Severino
- Department of Clinical, Internal, Anesthesiology and Cardiovascular Sciences, Sapienza University of Rome, Viale del Policlinico, 00185 Rome, Italy;
| | - Valentina Mercurio
- Department of Translational Medical Sciences, Federico II University, 80138 Naples, Italy;
| | - Damiano Magrì
- Department of Clinical and Molecular Medicine, Azienda Ospedaliera Sant’Andrea, “Sapienza” Università degli Studi di Roma, 00161 Rome, Italy;
| | - Frank Dini
- Istituto Auxologico IRCCS, Centro Medico Sant’Agostino, Via Temperanza, 6, 20127 Milan, Italy;
- Department of Public Health and Clinical Medicine, Umeå University, 901 87 Umeå, Sweden
| | - Roberto Licordari
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Section of Cardiology, University of Messina, 98122 Messina, Italy; (R.L.); (G.D.)
| | - Matteo Beltrami
- Arrhythmia and Electrophysiology Unit, Careggi University Hospital, 50134 Florence, Italy;
| | - Giuseppe Dattilo
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Section of Cardiology, University of Messina, 98122 Messina, Italy; (R.L.); (G.D.)
| | - Andrea Salzano
- Cardiology Unit, AORN A Cardarelli, 80131 Naples, Italy;
| | - Alberto Palazzuoli
- Cardiovascular Diseases Unit, Cardio-Thoracic and Vascular Department, S. Maria alle Scotte Hospital, University of Siena, 53100 Siena, Italy;
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Qi W, Mei Z, Sun Z, Lin C, Lin J, Li J, Ji JS, Zheng Y. Exposure to Multiple Air Pollutants and the Risk of Fractures: A Large Prospective Population-Based Study. J Bone Miner Res 2023; 38:1549-1559. [PMID: 37341992 DOI: 10.1002/jbmr.4872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/12/2023] [Accepted: 06/15/2023] [Indexed: 06/22/2023]
Abstract
Atmospheric chemistry studies suggest air pollution impedes ultraviolet B photons and thus reduces cutaneous vitamin D3 synthesis. Biological evidence shows that inhaled pollutants disrupt circulating 25-hydroxyvitamin D (25[OH]D) metabolism and ultimately impact bone health. The hypothesis is that higher air pollution concentrations are associated with a higher risk of fractures, mediated by lower circulating 25(OH)D. The study included participants of the UK Biobank who were free of fracture history at enrollment (2006 to 2010) and analyzed their environmental exposure data (2007 to 2010). Air pollution measurements included the annual averages of air particulate matter (PM2.5 , PM2.5-10 , and PM10 ), nitrogen oxides (NO2 and NOx ), and a composite air pollution score. Multivariable Cox proportional hazard models were used to assess the associations of the individual pollutants and the score with fracture risks. Mediation analyses were conducted to assess the underlying role of serum 25(OH)D in such associations. Among 446,395 participants with a median of 8-year follow-up, 12,288 incident fractures were documented. Participants living in places with the highest quintile of air pollution score had a 15.3% increased risk of fractures (hazard ratio [95%CI]: 1.15[1.09,1.22]) compared to those in the lowest, and 5.49% of this association was mediated through serum 25(OH)D (pmediation < 0.05). Pollutant-specific hazard of top-to-bottom quintiles was 16% for PM2.5 , 4% for PM2.5-10 , 5% for PM10 , 20% for NO2 , and 17% for NOx , with a 4% to 6% mediation effect of serum 25(OH)D concentrations. The associations of the air pollution score with fracture risks were weaker among female participants, those who drank less alcohol, and consumed more fresh fruit than their counterparts (pinteraction < 0.05). © 2023 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Wenhao Qi
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory of Contemporary Anthropology, Fudan University, Shanghai, China
| | - Zhendong Mei
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory of Contemporary Anthropology, Fudan University, Shanghai, China
| | - Zhonghan Sun
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory of Contemporary Anthropology, Fudan University, Shanghai, China
| | - Chenhao Lin
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory of Contemporary Anthropology, Fudan University, Shanghai, China
| | - Jinran Lin
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory of Contemporary Anthropology, Fudan University, Shanghai, China
| | - Jialin Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
| | - John S Ji
- Vanke School of Public Health, Tsinghua University, Beijing, China
| | - Yan Zheng
- State Key Laboratory of Genetic Engineering, School of Life Sciences and Human Phenome Institute, Fudan University, Shanghai, China
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
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McMahon TJ, Darrow CC, Hoehn BA, Zhu H. Generation and Export of Red Blood Cell ATP in Health and Disease. Front Physiol 2021; 12:754638. [PMID: 34803737 PMCID: PMC8602689 DOI: 10.3389/fphys.2021.754638] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/05/2021] [Indexed: 12/16/2022] Open
Abstract
Metabolic homeostasis in animals depends critically on evolved mechanisms by which red blood cell (RBC) hemoglobin (Hb) senses oxygen (O2) need and responds accordingly. The entwined regulation of ATP production and antioxidant systems within the RBC also exploits Hb-based O2-sensitivity to respond to various physiologic and pathophysiologic stresses. O2 offloading, for example, promotes glycolysis in order to generate both 2,3-DPG (a negative allosteric effector of Hb O2 binding) and ATP. Alternatively, generation of the nicotinamide adenine dinucleotide phosphate (NADPH) critical for reducing systems is favored under the oxidizing conditions of O2 abundance. Dynamic control of ATP not only ensures the functional activity of ion pumps and cellular flexibility, but also contributes to the availability of vasoregulatory ATP that can be exported when necessary, for example in hypoxia or upon RBC deformation in microvessels. RBC ATP export in response to hypoxia or deformation dilates blood vessels in order to promote efficient O2 delivery. The ability of RBCs to adapt to the metabolic environment via differential control of these metabolites is impaired in the face of enzymopathies [pyruvate kinase deficiency; glucose-6-phosphate dehydrogenase (G6PD) deficiency], blood banking, diabetes mellitus, COVID-19 or sepsis, and sickle cell disease. The emerging availability of therapies capable of augmenting RBC ATP, including newly established uses of allosteric effectors and metabolite-specific additive solutions for RBC transfusates, raises the prospect of clinical interventions to optimize or correct RBC function via these metabolite delivery mechanisms.
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Affiliation(s)
- Timothy J McMahon
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Durham VA and Duke University Medical Centers, Durham, NC, United States
| | - Cole C Darrow
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Durham VA and Duke University Medical Centers, Durham, NC, United States
| | - Brooke A Hoehn
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Durham VA and Duke University Medical Centers, Durham, NC, United States
| | - Hongmei Zhu
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Durham VA and Duke University Medical Centers, Durham, NC, United States
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Nitric oxide loading reduces sickle red cell adhesion and vaso-occlusion in vivo. Blood Adv 2020; 3:2586-2597. [PMID: 31484636 DOI: 10.1182/bloodadvances.2019031633] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 07/23/2019] [Indexed: 12/29/2022] Open
Abstract
Sickle red blood cells (SSRBCs) are adherent to the endothelium, activate leukocyte adhesion, and are deficient in bioactive nitric oxide (NO) adducts such as S-nitrosothiols (SNOs), with reduced ability to induce vasodilation in response to hypoxia. All these pathophysiologic characteristics promote vascular occlusion, the hallmark of sickle cell disease (SCD). Loading hypoxic SSRBCs in vitro with NO followed by reoxygenation significantly decreased epinephrine-activated SSRBC adhesion to the endothelium, the ability of activated SSRBCs to mediate leukocyte adhesion in vitro, and vessel obstruction in vivo. Because transfusion is frequently used in SCD, we also determined the effects of banked (SNO-depleted) red blood cells (RBCs) on vaso-occlusion in vivo. Fresh or 14-day-old normal RBCs (AARBCs) reduced epinephrine-activated SSRBC adhesion to the vascular endothelium and prevented vaso-occlusion. In contrast, AARBCs stored for 30 days failed to decrease activated SSRBC adhesivity or vaso-occlusion, unless these RBCs were loaded with NO. Furthermore, NO loading of SSRBCs increased S-nitrosohemoglobin and modulated epinephrine's effect by upregulating phosphorylation of membrane proteins, including pyruvate kinase, E3 ubiquitin ligase, and the cytoskeletal protein 4.1. Thus, abnormal SSRBC NO/SNO content both contributes to the vaso-occlusive pathophysiology of SCD, potentially by affecting at least protein phosphorylation, and is potentially amenable to correction by (S)NO repletion or by RBC transfusion.
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Oxidative Stress and Thrombosis during Aging: The Roles of Oxidative Stress in RBCs in Venous Thrombosis. Int J Mol Sci 2020; 21:ijms21124259. [PMID: 32549393 PMCID: PMC7352981 DOI: 10.3390/ijms21124259] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 01/17/2023] Open
Abstract
Mid-life stage adults are at higher risk of developing venous thrombosis (VT)/thromboembolism (VT/E). Aging is characterized by an overproduction of reactive oxygen species (ROS), which could evoke a series of physiological changes involved in thrombosis. Here, we focus on the critical role of ROS within the red blood cell (RBC) in initiating venous thrombosis during aging. Growing evidence has shifted our interest in the role of unjustifiably unvalued RBCs in blood coagulation. RBCs can be a major source of oxidative stress during aging, since RBC redox homeostasis is generally compromised due to the discrepancy between prooxidants and antioxidants. As a result, ROS accumulate within the RBC due to the constant endogenous hemoglobin (Hb) autoxidation and NADPH oxidase activation, and the uptake of extracellular ROS released by other cells in the circulation. The elevated RBC ROS level affects the RBC membrane structure and function, causing loss of membrane integrity, and decreased deformability. These changes impair RBC function in hemostasis and thrombosis, favoring a hypercoagulable state through enhanced RBC aggregation, RBC binding to endothelial cells affecting nitric oxide availability, RBC-induced platelet activation consequently modulating their activity, RBC interaction with and activation of coagulation factors, increased RBC phosphatidylserine exposure and release of microvesicles, accelerated aging and hemolysis. Thus, RBC oxidative stress during aging typifies an ultimate mechanism in system failure, which can affect major processes involved in the development of venous thrombosis in a variety of ways. The reevaluated concept of the critical role of RBC ROS in the activation of thrombotic events during aging will help identify potential targets for novel strategies to prevent/reduce the risk for VT/E or VT/E recurrences in mid-life stage adults.
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McMahon TJ. Red Blood Cell Deformability, Vasoactive Mediators, and Adhesion. Front Physiol 2019; 10:1417. [PMID: 31803068 PMCID: PMC6873820 DOI: 10.3389/fphys.2019.01417] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 11/01/2019] [Indexed: 01/16/2023] Open
Abstract
Healthy red blood cells (RBCs) deform readily in response to shear stress in the circulation, facilitating their efficient passage through capillaries. RBCs also export vasoactive mediators in response to deformation and other physiological and pathological stimuli. Deoxygenation of RBC hemoglobin leads to the export of vasodilator and antiadhesive S-nitrosothiols (SNOs) and adenosine triphosphate (ATP) in parallel with oxygen transport in the respiratory cycle. Together, these mediated responses to shear stress and oxygen offloading promote the efficient flow of blood cells and in turn optimize oxygen delivery. In diseases including sickle cell anemia and conditions including conventional blood banking, these adaptive functions may be compromised as a result, for example, of limited RBC deformability, impaired mediator formation, or dysfunctional mediator export. Ongoing work, including single cell approaches, is examining relevant mechanisms and remedies in health and disease.
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Affiliation(s)
- Timothy J McMahon
- Durham VA Medical Center, Duke University, Durham, NC, United States
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Veluswamy S, Shah P, Denton CC, Chalacheva P, Khoo MCK, Coates TD. Vaso-Occlusion in Sickle Cell Disease: Is Autonomic Dysregulation of the Microvasculature the Trigger? J Clin Med 2019; 8:jcm8101690. [PMID: 31618931 PMCID: PMC6832215 DOI: 10.3390/jcm8101690] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/11/2019] [Accepted: 10/11/2019] [Indexed: 02/02/2023] Open
Abstract
Sickle cell disease (SCD) is an inherited hemoglobinopathy characterized by polymerization of hemoglobin S upon deoxygenation that results in the formation of rigid sickled-shaped red blood cells that can occlude the microvasculature, which leads to sudden onsets of pain. The severity of vaso-occlusive crises (VOC) is quite variable among patients, which is not fully explained by their genetic and biological profiles. The mechanism that initiates the transition from steady state to VOC remains unknown, as is the role of clinically reported triggers such as stress, cold and pain. The rate of hemoglobin S polymerization after deoxygenation is an important determinant of vaso-occlusion. Similarly, the microvascular blood flow rate plays a critical role as fast-moving red blood cells are better able to escape the microvasculature before polymerization of deoxy-hemoglobin S causes the red cells to become rigid and lodge in small vessels. The role of the autonomic nervous system (ANS) activity in VOC initiation and propagation has been underestimated considering that the ANS is the major regulator of microvascular blood flow and that most triggers of VOC can alter the autonomic balance. Here, we will briefly review the evidence supporting the presence of ANS dysfunction in SCD, its implications in the onset of VOC, and how differences in autonomic vasoreactivity might potentially contribute to variability in VOC severity.
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Affiliation(s)
- Saranya Veluswamy
- Hematology Section, Children’s Center for Cancer and Blood Diseases, Children’s Hospital Los Angeles, 4650 Sunset boulevard, Los Angeles, CA 90027, USA; (S.V.); (P.S.); (C.C.D.)
| | - Payal Shah
- Hematology Section, Children’s Center for Cancer and Blood Diseases, Children’s Hospital Los Angeles, 4650 Sunset boulevard, Los Angeles, CA 90027, USA; (S.V.); (P.S.); (C.C.D.)
| | - Christopher C. Denton
- Hematology Section, Children’s Center for Cancer and Blood Diseases, Children’s Hospital Los Angeles, 4650 Sunset boulevard, Los Angeles, CA 90027, USA; (S.V.); (P.S.); (C.C.D.)
| | - Patjanaporn Chalacheva
- Department of Biomedical Engineering, University of Southern California, 1042 Downey Way, Los Angeles, CA 90089, USA; (P.C.)
| | - Michael C. K. Khoo
- Department of Biomedical Engineering, University of Southern California, 1042 Downey Way, Los Angeles, CA 90089, USA; (P.C.)
| | - Thomas D. Coates
- Hematology Section, Children’s Center for Cancer and Blood Diseases, Children’s Hospital Los Angeles, 4650 Sunset boulevard, Los Angeles, CA 90027, USA; (S.V.); (P.S.); (C.C.D.)
- Correspondence: ; Tel.: +1-323-361-2352
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Wu P, Shanminna, Liang K, Yue H, Qian L, Sun B. Exhaled nitric oxide is associated with postnatal adaptation to hypoxia in Tibetan and non-Tibetan newborn infants. Acta Paediatr 2016; 105:475-82. [PMID: 26776923 DOI: 10.1111/apa.13331] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 11/02/2015] [Accepted: 01/11/2016] [Indexed: 11/29/2022]
Abstract
AIM This Chinese study assessed partial pressure of exhaled nitric oxide (PeNO) in healthy Tibetan and non-Tibetan newborn infants born at a very high altitude. METHODS Full-term Tibetan and non-Tibetan neonates born in Lhasa, 3658 metres above sea level, were compared to non-Tibetan neonates born in Kunming (1891 m) and Huai'an (16 m). The chemiluminiscence technique was used to measure the fraction of exhaled nitric oxide during spontaneous tidal breathing and this was then converted to partial pressure of exhaled nitric oxide (PeNO). RESULTS In their first week, Tibetan and non-Tibetan neonates born in Lhasa had persistently higher PeNO levels than non-Tibetan neonates born in Kunming and Huai'an, which was further verified by partial pressure of inspired oxygen adjustment. However, the non-Tibetans born in Lhasa required short-term oxygen therapy to improve their early postnatal oxygenation. The temporal changes of PeNO and cardio-respiratory function measurements demonstrated that Tibetan and non-Tibetan newborns in Lhasa initially needed to adapt to attain homoeostasis in oxygenation and gas exchange. CONCLUSION Tibetan and non-Tibetan newborn infants living at the same high altitude demonstrated comparable PeNO levels during postnatal adaptation to hypobaric hypoxia, which warrants further investigation of the mechanism of endogenous nitric oxide and hypoxic tolerance.
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Affiliation(s)
- Panpan Wu
- Department of Pediatrics; Children's Hospital of Fudan University; and the Laboratory of Neonatal Medicine of National Health and Family Planning Commission; Shanghai China
| | - Shanminna
- Department of Pediatrics; Tibet Autonomous Regional People's Hospital; Lhasa Tibet China
| | - Kun Liang
- Department of Pediatrics; First General Hospital of Kunming Medical University; Kunming Yunnan China
| | - Hongni Yue
- Department of Pediatrics; Huai'an Women and Children's Hospital; Huai'an Jiangsu China
| | - Liling Qian
- Department of Pediatrics; Children's Hospital of Fudan University; and the Laboratory of Neonatal Medicine of National Health and Family Planning Commission; Shanghai China
| | - Bo Sun
- Department of Pediatrics; Children's Hospital of Fudan University; and the Laboratory of Neonatal Medicine of National Health and Family Planning Commission; Shanghai China
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S-Nitrosylated fetal hemoglobin in neonatal human blood. Biochem Biophys Res Commun 2016; 473:1084-1089. [PMID: 27060546 DOI: 10.1016/j.bbrc.2016.04.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 04/05/2016] [Indexed: 11/24/2022]
Abstract
BACKGROUND Nitric oxide (NO) and its derivatives play important roles in the cardiopulmonary transition upon birth and in other oxygen-sensitive developmental milestones. One mechanism for the coupling of oxygen sensing and signaling by NO species is via the formation of an S-nitrosothiol (SNO) moiety on hemoglobin (Hb, forming SNO-Hb) and its release from the red blood cell in hypoxia. Although SNO-Hb formed on adult-type Hb (HbA, forming SNO-HbA) has been documented in physiological and pathophysiological human states, the fetal variant, SNO-HbF, has thus far not been isolated or characterized in human blood. METHODS AND RESULTS We developed a technique capable of separating Hbs A and F under conditions that preserve SNO. We then measured SNO-HbF in the blood of healthy and premature or otherwise ill neonates using the gold standard for SNO measurement, mercury-coupled photolysis-chemiluminescence. SNO-HbF levels were in the range of those previously reported for HbA in adults. We found that SNO-HbF was more abundant at earlier gestational age (<30 weeks), even when accounting for the absolute HbF level. CONCLUSIONS The ability to monitor SNO-HbF could provide new insights into fetal development and the perinatal transition, and has potential as a biomarker relevant to the management of neonatal diseases.
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Swaminathan AC, Dusek AC, McMahon TJ. Treatment-related biomarkers in pulmonary hypertension. Am J Respir Cell Mol Biol 2015; 52:663-73. [PMID: 25611885 DOI: 10.1165/rcmb.2014-0438tr] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Significant advances in the treatment of pulmonary arterial hypertension (PAH) over the last two decades have led to the introduction of multiple classes of oral therapy, but the disease remains devastating for many patients. Disease progression, in spite of oral monotherapy, is a major problem, and alternative therapy, such as infusion of prostacyclins, is cumbersome and carries considerable potential morbidity. Use of combination oral therapy, including drugs from both the endothelin receptor antagonist and phosphodiesterase-5 inhibitor classes, has increased, and there is some evidence to support this approach. Given the multiple options now available in pulmonary hypertension (PH) therapy, biomarkers to guide treatment decisions could be helpful. Here, we review the evidence for and against the clinical use of molecular biomarkers relevant to PH pathogenesis, emphasizing assayable markers that may also inform more rational selection of agents that influence pathways targeted by treatment. We emphasize the interactive nature of changes in mediators and messengers, such as endothelin-1, prostacyclin, brain natriuretic peptide (which has demonstrated biomarker utility), nitric oxide derivatives, and cyclic guanosine monophosphate, which play important roles in processes central to progression of PAH, such as vascular remodeling, vasoconstriction, and maladaptive right ventricular changes, and are relevant to its therapy. Accordingly, we propose that the identification and use of a molecular biomarker panel that assays these molecules in parallel and serially might, if validated, better inform unique patient phenotypes, prognosis, and the rational selection and titration of combination oral and other therapy in individual patients with PH/PAH.
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Affiliation(s)
- Aparna C Swaminathan
- 1 Duke University and Durham Department of Veterans Affairs Medical Centers, Durham, North Carolina; and
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NO to cancer: The complex and multifaceted role of nitric oxide and the epigenetic nitric oxide donor, RRx-001. Redox Biol 2015; 6:1-8. [PMID: 26164533 PMCID: PMC4529402 DOI: 10.1016/j.redox.2015.07.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 06/30/2015] [Accepted: 07/01/2015] [Indexed: 01/18/2023] Open
Abstract
The endogenous mediator of vasodilation, nitric oxide (NO), has been shown to be a potent radiosensitizer. However, the underlying mode of action for its role as a radiosensitizer – while not entirely understood – is believed to arise from increased tumor blood flow, effects on cellular respiration, on cell signaling, and on the production of reactive oxygen and nitrogen species (RONS), that can act as radiosensitizers in their own right. NO activity is surprisingly long-lived and more potent in comparison to oxygen. Reports of the effects of NO with radiation have often been contradictory leading to confusion about the true radiosensitizing nature of NO. Whether increasing or decreasing tumor blood flow, acting as radiosensitizer or radioprotector, the effects of NO have been controversial. Key to understanding the role of NO as a radiosensitizer is to recognize the importance of biological context. With a very short half-life and potent activity, the local effects of NO need to be carefully considered and understood when using NO as a radiosensitizer. The systemic effects of NO donors can cause extensive side effects, and also affect the local tumor microenvironment, both directly and indirectly. To minimize systemic effects and maximize effects on tumors, agents that deliver NO on demand selectively to tumors using hypoxia as a trigger may be of greater interest as radiosensitizers. Herein we discuss the multiple effects of NO and focus on the clinical molecule RRx-001, a hypoxia-activated NO donor currently being investigated as a radiosensitizer in the clinic. . NO radiosensitizes by reaction with DNA radicals, by its metabolites and by impact on the vasculature. Understanding the local and context-specific activity of NO is key for radiosensitizer development RRx-001 induces NO production under hypoxia with promising radiosensitizing activity.
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Abstract
PURPOSE OF REVIEW Oxygen (O2) delivery, the maintenance of which is fundamental to supporting those with critical illness, is a function of blood O2 content and flow. Here, we review red blood cell (RBC) physiology relevant to disordered O2 delivery in the critically ill. RECENT FINDINGS Flow (rather than content) is the focus of O2 delivery regulation. O2 content is relatively fixed, whereas flow fluctuates by several orders of magnitude. Thus, blood flow volume and distribution vary to maintain coupling between O2 delivery and demand. The trapping, processing and delivery of nitric oxide (NO) by RBCs has emerged as a conserved mechanism through which regional blood flow is linked to biochemical cues of perfusion sufficiency. We will review conventional RBC physiology that influences O2 delivery (O2 affinity & rheology) and introduce a new paradigm for O2 delivery homeostasis based on coordinated gas transport and vascular signaling by RBCs. SUMMARY By coordinating vascular signaling in a fashion that links O2 and NO flux, RBCs couple vessel caliber (and thus blood flow) to O2 need in tissue. Malfunction of this signaling system is implicated in a wide array of pathophysiologies and may be explanatory for the dysoxia frequently encountered in the critical care setting.
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13
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Yeom E, Lee SJ. Microfluidic-based speckle analysis for sensitive measurement of erythrocyte aggregation: A comparison of four methods for detection of elevated erythrocyte aggregation in diabetic rat blood. BIOMICROFLUIDICS 2015; 9:024110. [PMID: 25945136 PMCID: PMC4385097 DOI: 10.1063/1.4917023] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 03/26/2015] [Indexed: 05/15/2023]
Abstract
Biochemical alterations in the plasma and red blood cell (RBC) membrane of diabetic blood lead to excessive erythrocyte aggregation (EA). EA would significantly impede the blood flow and increase the vascular flow resistance contributing to peripheral vascular diseases. In this study, a simple microfluidic-based method is proposed to achieve sensitive detection of hyperaggregation. When a blood sample is delivered into the device, images of blood flows are obtained with a short exposure time for a relatively long measuring time. A micro-particle image velocimetry technique was employed to monitor variation of the flow rate of blood as a function of time. Given that EA formation in the channel creates clear speckle patterns, the EA extent can be estimated by calculating a speckle area (ASpeckle) through a normalized autocovariance function. The hematocrit effect is assessed by comparing optical images transmitted through blood samples. EA variations caused by dextran treatment are quantitatively evaluated using characteristic time (λSpeckle) obtained by fitting the variations of ASpeckle. Other indices including number of RBCs in an aggregate (NRBC), characteristic time of erythrocyte sedimentation rate (λESR), and aggregation index estimated from ultrasound signals (AIEcho) are determined under different EA conditions using conventional techniques. The four different methods are applied to diabetic blood samples to compare their indices under hyperaggregation conditions. It is found that the proposed method can detect variation of EA reasonably, compared with conventional measurement techniques. These experimental demonstrations support the notion that the proposed method is capable of effectively monitoring the biophysical properties of diabetic blood.
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Affiliation(s)
- Eunseop Yeom
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, South Korea
| | - Sang Joon Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, South Korea
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14
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Abstract
A previous experiment using an in vivo mouse model has proved that hypoxia increased angiogenesis during wound healing. It was hypothesised that one of the mechanisms for wound healing impairment in diabetes includes insufficient angiogenic ability in response to hypoxia. The current study aims to investigate the influence of hypoxia on wound healing in diabetic mice. Oxygen-impermeable (hypoxic group) and -permeable membranes (normoxic group) were used to control topical oxygen tension. Membranes were applied to symmetrical excisional wounds on diabetic mice. Wound area, granulated tissue thickness, and vascular density were analyzed. As results, a decrease in wound size on day 7 was observed in the normoxic group (20.7 ± 3.64%) compared with the hypoxic group (34.1 ± 4.98%). The normoxic group also showed significantly thicker granulated tissue than the hypoxic group (225.7 ± 54.7 vs 128.7 ± 42.4 µm). There was no significant difference in mean vascular density between normoxic and hypoxic groups (0.046 ± 0.022 vs 0.038 ± 0.017 mm(2)/mm(2), p = 0.80). Contrary to healthy mice, diabetic mice have shown no enhancement of angiogenesis in hypoxic condition. The findings illustrate that neovascularisation in response to hypoxia is diminished in diabetic wounds.
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Affiliation(s)
- Hitomi Sano
- Department of Surgical Science, Graduate School of Medicine, University of Tokyo , Tokyo , Japan
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15
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Umbrello M, Dyson A, Feelisch M, Singer M. The key role of nitric oxide in hypoxia: hypoxic vasodilation and energy supply-demand matching. Antioxid Redox Signal 2013; 19:1690-710. [PMID: 23311950 DOI: 10.1089/ars.2012.4979] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
SIGNIFICANCE A mismatch between energy supply and demand induces tissue hypoxia with the potential to cause cell death and organ failure. Whenever arterial oxygen concentration is reduced, increases in blood flow--hypoxic vasodilation--occur in an attempt to restore oxygen supply. Nitric oxide (NO) is a major signaling and effector molecule mediating the body's response to hypoxia, given its unique characteristics of vasodilation (improving blood flow and oxygen supply) and modulation of energetic metabolism (reducing oxygen consumption and promoting utilization of alternative pathways). RECENT ADVANCES This review covers the role of oxygen in metabolism and responses to hypoxia, the hemodynamic and metabolic effects of NO, and mechanisms underlying the involvement of NO in hypoxic vasodilation. Recent insights into NO metabolism will be discussed, including the role for dietary intake of nitrate, endogenous nitrite (NO₂⁻) reductases, and release of NO from storage pools. The processes through which NO levels are elevated during hypoxia are presented, namely, (i) increased synthesis from NO synthases, increased reduction of NO₂⁻ to NO by heme- or pterin-based enzymes and increased release from NO stores, and (ii) reduced deactivation by mitochondrial cytochrome c oxidase. CRITICAL ISSUES Several reviews covered modulation of energetic metabolism by NO, while here we highlight the crucial role NO plays in achieving cardiocirculatory homeostasis during acute hypoxia through both vasodilation and metabolic suppression. FUTURE DIRECTIONS We identify a key position for NO in the body's adaptation to an acute energy supply-demand mismatch.
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Affiliation(s)
- Michele Umbrello
- 1 Department of Medicine, Bloomsbury Institute of Intensive Care Medicine, University College London , London, United Kingdom
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16
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Optimization of Tumor Radiotherapy With Modulators of Cell Metabolism: Toward Clinical Applications. Semin Radiat Oncol 2013; 23:262-72. [DOI: 10.1016/j.semradonc.2013.05.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Jordan BF, Sonveaux P. Targeting tumor perfusion and oxygenation to improve the outcome of anticancer therapy. Front Pharmacol 2012; 3:94. [PMID: 22661950 PMCID: PMC3357106 DOI: 10.3389/fphar.2012.00094] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 04/30/2012] [Indexed: 11/13/2022] Open
Abstract
Radiotherapy and chemotherapy are widespread clinical modalities for cancer treatment. Among other biological influences, hypoxia is a main factor limiting the efficacy of radiotherapy, primarily because oxygen is involved in the stabilization of the DNA damage caused by ionizing radiations. Radiobiological hypoxia is found in regions of rodent and human tumors with a tissue oxygenation level below 10 mmHg at which tumor cells become increasingly resistant to radiation damage. Since hypoxic tumor cells remain clonogenic, their resistance to the treatment strongly influences the therapeutic outcome of radiotherapy. There is therefore an urgent need to identify adjuvant treatment modalities aimed to increase tumor pO(2) at the time of radiotherapy. Since tumor hypoxia fundamentally results from an imbalance between oxygen delivery by poorly efficient blood vessels and oxygen consumption by tumor cells with high metabolic activities, two promising approaches are those targeting vascular reactivity and tumor cell respiration. This review summarizes the current knowledge about the development and use of tumor-selective vasodilators, inhibitors of tumor cell respiration, and drugs and treatments combining both activities in the context of tumor sensitization to X-ray radiotherapy. Tumor-selective vasodilation may also be used to improve the delivery of circulating anticancer agents to tumors. Imaging tumor perfusion and oxygenation is of importance not only for the development and validation of such combination treatments, but also to determine which patients could benefit from the therapy. Numerous techniques have been developed in the preclinical setting. Hence, this review also briefly describes both magnetic resonance and non-magnetic resonance in vivo methods and compares them in terms of sensitivity, quantitative or semi-quantitative properties, temporal, and spatial resolutions, as well as translational aspects.
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Affiliation(s)
- Bénédicte F. Jordan
- Nuclear Magnetic Resonance Research Group, Louvain Drug Research Institute, Université catholique de Louvain Medical SchoolBrussels, Belgium
| | - Pierre Sonveaux
- Pole of Pharmacology, Institute of Experimental and Clinical Research, Université Catholique de Louvain Medical SchoolBrussels, Belgium
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18
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Is Nitric Oxide (NO) the Last Word in Radiosensitization? A Review. Transl Oncol 2012; 5:66-71. [PMID: 22496921 DOI: 10.1593/tlo.11307] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 12/03/2011] [Accepted: 12/07/2011] [Indexed: 12/20/2022] Open
Abstract
As a short-lived radical that diffuses across membranes, rather than interacting with membrane-bound receptors, nitric oxide (NO) represents a significant departure from synthetically derived radiosensitizers. An endogenous compound, NO may equal or surpass its molecular cousin, oxygen, as a hypoxic radiosensitizer, through pleiotropic phenotypic effects on tumor perfusion, cell signaling, mitochondrial respiration, the fixation of radiation-induced damage, and the radioprotection of normal tissue. However, unlike oxygen, in the context of radiosensitization, the clinical role and utility of NO are poorly understood, with often contradictory and controversial reported effects: whether NO functions as a radiosensitizer may ultimately be contextual to the tumor microenvironment. This may make NO manipulation an ideal candidate for a personalized radiosensitization approach tailored to specific patient and tumor types/microenvironmental characteristics. Effective delivery of NO both systemically and directly to the tumor may be critical to the success of this approach. Compounds that release NO or NO precursors have the potential to drive innovation and result in a new fertile branch of the radiosensitizer tree.
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19
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Inhaled nitric oxide improves systemic microcirculation in infants with hypoxemic respiratory failure. Pediatr Crit Care Med 2011; 12:e271-4. [PMID: 21297516 DOI: 10.1097/pcc.0b013e31820ac0b3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To investigate the effect of inhaled nitric oxide on the systemic microcirculation. We hypothesized that inhaled nitric oxide improves the systemic microcirculation. Inhaled nitric oxide improves outcome in infants with persistent pulmonary hypertension of the newborn diagnosed by improving pulmonary blood flow and oxygenation. It reduces pulmonary vascular resistance without decline in systemic blood pressure. Inhaled nitric oxide is also utilized in the treatment of acute hypoxemic respiratory failure in children and adults. It is thought to improve regional ventilation perfusion by regional selective pulmonary vasodilation. DESIGN Pilot study. SETTING Intensive care unit of a level III university children's hospital. PATIENTS Consecutive ventilated patients who were treated with inhaled nitric oxide (20 ppm) were enrolled in this study. Eight patients (five boys, three girls) were included; five had congenital diaphragmatic hernia diagnosed, one had persistent pulmonary hypertension of the newborn diagnosed, one had acute respiratory distress syndrome diagnosed, and one had bronchiolitis diagnosed. The median age was 0 months (range, 0-38 months). INTERVENTIONS Inhaled nitric oxide administration. MEASUREMENTS AND MAIN RESULTS The microcirculation was assessed in the buccal mucosa within 1 hr before and within 1 hr after the start of inhaled nitric oxide using orthogonal polarization spectral imaging. The median functional capillary density before the inhaled nitric oxide was started was 4.0 cm/cm (range, 1.8-5.6 cm/cm) and improved to 4.9 cm/cm (range, 2.8-6.6 cm/cm; p = .017) after the start of inhaled nitric oxide. CONCLUSIONS Inhaled nitric oxide improves the systemic microcirculation in children with hypoxemic respiratory failure.
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Weinberg JA, Barnum SR, Patel RP. Red blood cell age and potentiation of transfusion-related pathology in trauma patients. Transfusion 2011; 51:867-73. [PMID: 21496048 DOI: 10.1111/j.1537-2995.2011.03098.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The specific negative clinical manifestations associated with the transfusion of stored red blood cells (RBCs) and the corresponding mechanisms responsible for such phenomena remain poorly defined. Our recent studies document that leukoreduced older RBC units potentiate transfusion-related toxicity in trauma patients. It is our hypothesis that the transfusion of relatively older blood impedes microvascular perfusion. The central mechanisms proposed to mediate this microcirculatory alteration include: 1) the loss of RBC-dependent control of nitric oxide-mediated homeostasis concerning vasodilation and 2) immune cell and complement activation. In this review, we outline the background for our hypothesis and detail our current investigations toward the understanding of this pathophysiology.
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Affiliation(s)
- Jordan A Weinberg
- Department of Surgery, University of Tennessee Health Science Center, 910 Madison Avenue, #224, Memphis, TN 38103, USA.
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21
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Buehler PW, Karnaukhova E, Gelderman MP, Alayash AI. Blood aging, safety, and transfusion: capturing the "radical" menace. Antioxid Redox Signal 2011; 14:1713-28. [PMID: 20954814 DOI: 10.1089/ars.2010.3447] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Throughout their life span, circulating red blood cells (RBCs) transport oxygen (O(2)) primarily from the lungs to tissues and return with carbon dioxide (CO(2)) from respiring tissues for final elimination by lungs. This simplistic view of RBCs as O(2) transporter has changed in recent years as other gases, for example, nitric oxide (NO), and small molecules, such as adenosine triphosphate (ATP), have been shown to either be produced and/or carried by RBCs to perform other signaling and O(2) sensing functions. In spite of the numerous biochemical and metabolic changes occurring within RBCs during storage, prior to, and after transfusion, perturbations of RBC membrane are likely to affect blood flow in the microcirculation. Subsequent hemolysis due to storage conditions and/or hemolytic disorders may have some pathophysiological consequences as a result of the release of Hb. In this review, we show that evolution has provided a multitude of protection and intervention strategies against free Hb from "cradle" to "death"; from early biosynthesis to its final degradation and a lot more in between. Furthermore, some of the same naturally occurring protective mechanisms can potentially be employed to oxidatively inactivate this redox active protein and control its damaging side reactions when released outside of the RBC.
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Affiliation(s)
- Paul W Buehler
- Division of Hematology, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, Maryland 20892, USA
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22
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Ikuta T, Thatte HS, Tang JX, Mukerji I, Knee K, Bridges KR, Wang S, Montero-Huerta P, Joshi RM, Head CA. Nitric oxide reduces sickle hemoglobin polymerization: potential role of nitric oxide-induced charge alteration in depolymerization. Arch Biochem Biophys 2011; 510:53-61. [PMID: 21457702 DOI: 10.1016/j.abb.2011.03.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/25/2011] [Accepted: 03/27/2011] [Indexed: 11/30/2022]
Abstract
We previously demonstrated that inhaling nitric oxide (NO) increases the oxygen affinity of sickle red blood cells (RBCs) in patients with sickle cell disease (SCD). Our recent studies found that NO lowered the P(50) values of sickle hemoglobin (HbS) hemolysates but did not increase methemoglobin (metHb) levels, supporting the role of NO, but not metHb, in the oxygen affinity of HbS. Here we examine the mechanism by which NO increases HbS oxygen affinity. Because anti-sickling agents increase sickle RBC oxygen affinity, we first determined whether NO exhibits anti-sickling properties. The viscosity of HbS hemolysates, measured by falling ball assays, increased upon deoxygenation; NO treatment reduced the increment. Multiphoton microscopic analyses showed smaller HbS polymers in deoxygenated sickle RBCs and HbS hemolysates exposed to NO. These results suggest that NO inhibits HbS polymer formation and has anti-sickling properties. Furthermore, we found that HbS treated with NO exhibits an isoelectric point similar to that of HbA, suggesting that NO alters the electric charge of HbS. NO-HbS adducts had the same elution time as HbA upon high performance liquid chromatography analysis. This study demonstrates that NO may disrupt HbS polymers by abolishing the excess positive charge of HbS, resulting in increased oxygen affinity.
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Affiliation(s)
- Tohru Ikuta
- Department of Anesthesiology and Perioperative Medicine, Georgia Health Sciences University, Augusta, 30912, United States
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23
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Alayash AI. Haptoglobin: old protein with new functions. Clin Chim Acta 2010; 412:493-8. [PMID: 21159311 DOI: 10.1016/j.cca.2010.12.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 12/06/2010] [Accepted: 12/07/2010] [Indexed: 11/25/2022]
Abstract
When released from red blood cells (RBCs), hemoglobin (Hb) is extremely toxic due in large part to the redox activity of its heme center. Nature however, has provided a multitude of protective mechanisms that can detoxify free Hb effectively under physiological conditions. Chief amongst them is haptoglobin (Hp) which chaperones Hb subunits to the macrophages for safe degradation. Recent research on the interactions between Hb and Hp under oxidative conditions revealed that Hp specifically shields key amino acids on the Hb molecule, allowing the heme to consume oxidants and short-circuits the emerging and damaging radicals. Moreover, animal studies showed that the infusion of Hb complexed with Hp prevents Hb-induced systemic hypertension and tissue injury. It may prove necessary to explore these protective clearing mechanisms to counter the toxicity associated with free Hb when used as oxygen therapeutics in hemolytic anemias and in RBC storage lesions.
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Affiliation(s)
- Abdu I Alayash
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and Research, US Food and Drug Administration, Bethesda, MD 20892, USA.
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24
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Tommila M, Stark C, Jokilammi A, Peltonen V, Penttinen R, Ekholm E. Hemoglobin expression in rat experimental granulation tissue. J Mol Cell Biol 2010; 3:190-6. [PMID: 21059732 DOI: 10.1093/jmcb/mjq036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The general opinion that hemoglobin is only a carrier protein for oxygen and carbon dioxide has been challenged by several recent studies showing hemoglobin expression in other cells than those of the erythroid series, for example, in macrophages. We discovered β-globin expression in rat experimental granulation tissue induced by subcutaneously implanted cellulose sponges. Closer investigation revealed also α-globin expression. The first peak of the biphasic globin expression noticed during granulation tissue formation correlated with the invasion of monocytes/macrophages, whereas the second one seemed to be connected to the appearance of hematopoietic progenitors. Data presented in this study indicate globin expression both in macrophages and in immature erythroid cells as validated by erythroid-specific markers.
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Affiliation(s)
- Miretta Tommila
- Department of Medical Biochemistry and Genetics, University of Turku, Turku, Finland
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25
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Abstract
Well over 2 decades have passed since the endothelium-derived relaxation factor was reported to be the gaseous molecule nitric oxide (NO). Although soluble guanylyl cyclase (which generates cyclic guanosine monophosphate, cGMP) was the first identified receptor for NO, it has become increasingly clear that NO exerts a ubiquitous influence in a cGMP-independent manner. In particular, many, if not most, effects of NO are mediated by S-nitrosylation, the covalent modification of a protein cysteine thiol by an NO group to generate an S-nitrosothiol (SNO). Moreover, within the current framework of NO biology, endothelium-derived relaxation factor activity (ie, G protein-coupled receptor-mediated, or shear-induced endothelium-derived NO bioactivity) is understood to involve a central role for SNOs, acting both as second messengers and signal effectors. Furthermore, essential roles for S-nitrosylation have been implicated in virtually all major functions of NO in the cardiovascular system. Here, we review the basic biochemistry of S-nitrosylation (and denitrosylation), discuss the role of S-nitrosylation in the vascular and cardiac functions of NO, and identify current and potential clinical applications.
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Affiliation(s)
- Brian Lima
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
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26
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Jensen FB. The dual roles of red blood cells in tissue oxygen delivery: oxygen carriers and regulators of local blood flow. ACTA ACUST UNITED AC 2010; 212:3387-93. [PMID: 19837879 DOI: 10.1242/jeb.023697] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Vertebrate red blood cells (RBCs) seem to serve tissue oxygen delivery in two distinct ways. Firstly, RBCs enable the adequate transport of O(2) between respiratory surfaces and metabolizing tissues by means of their high intracellular concentration of hemoglobin (Hb), appropriate allosteric interactions between Hb ligand-binding sites, and an adjustable intracellular chemical environment that allows fine-tuning of Hb O(2) affinity. Secondly, RBCs may sense tissue O(2) requirements via their degree of deoxygenation when they travel through the microcirculation and release vasodilatory compounds that enhance blood flow in hypoxic tissues. This latter function could be important in matching tissue O(2) delivery with local O(2) demand. Three main mechanisms by which RBCs can regulate their own distribution in the microcirculation have been proposed. These are: (1) deoxygenation-dependent release of ATP from RBCs, which stimulates production of nitric oxide (NO) and other vasodilators in the endothelium; (2) release of vasoactive NO from S-nitroso-Hb upon deoxygenation; and (3) reduction of naturally occurring nitrite to vasoactive NO by deoxygenated Hb. This Commentary inspects all three hypotheses with regard to their mechanisms, experimental evidence in their support and details that remain unresolved. The prime focus is on human/mammalian models, where most evidence for a role of erythrocyte ATP and NO release in blood flow regulation have accumulated. Information from other vertebrate groups is integrated in the analysis and used to discuss the evolutionary origin and general relevance of each hypothesis.
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Affiliation(s)
- Frank B Jensen
- Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
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27
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de Almeida JPL, Freitas-Santos T, Saldanha C. Fibrinogen-dependent signaling in microvascular erythrocyte function: implications on nitric oxide efflux. J Membr Biol 2009; 231:47-53. [PMID: 19809847 DOI: 10.1007/s00232-009-9204-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Accepted: 09/14/2009] [Indexed: 10/20/2022]
Abstract
Experimental evidence has shown that plasma fibrinogen plays a key role as a major cardiovascular risk factor, acting directly to trigger erythrocyte aggregation in occlusive vascular disease. However, due to the complex and hitherto unclear interaction between fibrinogen and the erythrocyte membrane, no study has yet evaluated the effects of fibrinogen, under physiological range values, on the erythrocyte nitric oxide (NO) mobilization. Taking into consideration the potential NO-derived molecules, we have raised the hypothesis that fibrinogen, under physiological conditions, may act to influence blood flow via erythrocyte NO modulation. In this in vitro study whole-blood samples were harvested from healthy subjects, erythrocyte suspensions were incubated in the absence (control aliquots) and presence of different fibrinogen concentrations and levels of NO, nitrite, nitrate and S-nitroglutathione (GSNO) were determined. Our results showed, when compared with control aliquots, that the presence of fibrinogen modulates the NO mobilization in erythrocytes by (1) decreasing erythrocyte NO efflux levels (P < 0.001); (2) increasing levels of intraerythrocytic NO oxidative metabolites, namely, nitrite (P < 0.0001) and nitrate (P < 0.0001); and (3) enhancing the formation of GSNO (P < 0.001). In conclusion, this study provides new insights into an unknown mechanism by which fibrinogen modulates the erythrocyte capacity to supply NO, the effects of which on inflammation profiles (generally associated with blood hyperviscosity and hyperaggregation) still need to be elucidated. Also, increased erythrocyte GSNO levels may be associated with platelet NO metabolism, its activation status and hypotension, which may be extremely relevant in the clinical setting as biomarkers.
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28
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Bischoff P, Altmeyer A, Dumont F. Radiosensitising agents for the radiotherapy of cancer: advances in traditional and hypoxia targeted radiosensitisers. Expert Opin Ther Pat 2009; 19:643-62. [DOI: 10.1517/13543770902824172] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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29
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Sonveaux P, Jordan BF, Gallez B, Feron O. Nitric oxide delivery to cancer: Why and how? Eur J Cancer 2009; 45:1352-69. [DOI: 10.1016/j.ejca.2008.12.018] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 12/12/2008] [Indexed: 02/07/2023]
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30
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Forgan LG, Forster ME. Oxygen consumption and blood flow distribution in perfused skeletal muscle of chinook salmon. J Comp Physiol B 2008; 179:359-68. [DOI: 10.1007/s00360-008-0320-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 11/13/2008] [Accepted: 11/18/2008] [Indexed: 10/21/2022]
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31
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GIBSON CMICHAEL. Antiplatelet Therapy: Anti-Ischemic Benefits versus Bleeding Risk. J Interv Cardiol 2008; 21 Suppl 1:S3-9. [DOI: 10.1111/j.1540-8183.2008.00407.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Chen K, Pittman RN, Popel AS. Nitric oxide in the vasculature: where does it come from and where does it go? A quantitative perspective. Antioxid Redox Signal 2008; 10:1185-98. [PMID: 18331202 PMCID: PMC2932548 DOI: 10.1089/ars.2007.1959] [Citation(s) in RCA: 187] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Nitric oxide (NO) affects two key aspects of O2 supply and demand: It regulates vascular tone and blood flow by activating soluble guanylate cyclase (sGC) in the vascular smooth muscle, and it controls mitochondrial O2 consumption by inhibiting cytochrome c oxidase. However, significant gaps exist in our quantitative understanding of the regulation of NO production in the vascular region. Large apparent discrepancies exist among the published reports that have analyzed the various pathways in terms of the perivascular NO concentration, the efficacy of NO in causing vasodilation (EC50), its efficacy in tissue respiration (IC50), and the paracrine and endocrine NO release. In this study, we review the NO literature, analyzing NO levels on various scales, identifying and analyzing the discrepancies in the reported data, and proposing hypotheses that can potentially reconcile these discrepancies. Resolving these issues is highly relevant to improving our understanding of vascular biology and to developing pharmaceutical agents that target NO pathways, such as vasodilating drugs.
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Affiliation(s)
- Kejing Chen
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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33
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Frérart F, Sonveaux P, Rath G, Smoos A, Meqor A, Charlier N, Jordan BF, Saliez J, Noël A, Dessy C, Gallez B, Feron O. The Acidic Tumor Microenvironment Promotes the Reconversion of Nitrite into Nitric Oxide: Towards a New and Safe Radiosensitizing Strategy. Clin Cancer Res 2008; 14:2768-74. [DOI: 10.1158/1078-0432.ccr-07-4001] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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34
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Sonveaux P. Provascular strategy: Targeting functional adaptations of mature blood vessels in tumors to selectively influence the tumor vascular reactivity and improve cancer treatment. Radiother Oncol 2008; 86:300-13. [DOI: 10.1016/j.radonc.2008.01.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 01/30/2008] [Accepted: 01/30/2008] [Indexed: 12/22/2022]
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35
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Angelo M, Hausladen A, Singel DJ, Stamler JS. Interactions of NO with hemoglobin: from microbes to man. Methods Enzymol 2008; 436:131-68. [PMID: 18237631 DOI: 10.1016/s0076-6879(08)36008-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hemoglobins are found in organisms from every major phylum and subserve life-sustaining respiratory functions across a broad continuum. Sustainable aerobic respiration in mammals and birds relies on the regulated delivery of oxygen (O2) and nitric oxide (NO) bioactivity by hemoglobin, through reversible binding of NO and O2 to hemes as well as S-nitrosylation of cysteine thiols (SNO synthase activity). In contrast, bacterial and yeast flavohemoglobins function in vivo as denitrosylases (O2 nitroxylases), and some multimeric, invertebrate hemoglobins function as deoxygenases (Cys-dependent NO dioxygenases), which efficiently consume rather than deliver NO and O2, respectively. Analogous mechanisms may operate in plants. Bacteria and fungi deficient in flavohemoglobin show compromised virulence in animals that results from impaired resistance to NO, whereas animals and humans deficient in S-nitrosylated Hb exhibit altered vasoactivity. NO-related functions of hemoglobins center on reactions with ferric (FeIII) heme iron, which is exploited in enzymatic reactions that address organismal requirements for delivery or detoxification of NO and O2. Delivery versus detoxification of NO/O2 is largely achieved through structural changes and amino acid rearrangements within the heme pockets, thereby influencing the propensity for heme/cysteine thiol redox coupling. Additionally, the behavior exhibited by hemoglobin in vivo may be profoundly dependent both on the abundance of NO and O2 and on the allosteric effects of heterotropic ligands. Here we review well-documented examples of redox interactions between NO and hemoglobin, with an emphasis on biochemical mechanisms and physiological significance.
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Affiliation(s)
- Michael Angelo
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana
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Reynolds JD, Ahearn GS, Angelo M, Zhang J, Cobb F, Stamler JS. S-nitrosohemoglobin deficiency: a mechanism for loss of physiological activity in banked blood. Proc Natl Acad Sci U S A 2007; 104:17058-62. [PMID: 17940022 PMCID: PMC2040473 DOI: 10.1073/pnas.0707958104] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Indexed: 11/18/2022] Open
Abstract
RBCs distribute oxygen to tissues, but, paradoxically, blood transfusion does not always improve oxygen delivery and is associated with ischemic events. We hypothesized that storage of blood would result in loss of NO bioactivity, impairing RBC vasodilation and thus compromising blood flow, and that repleting NO bioactivity would restore RBC function. We report that S-nitrosohemoglobin (SNO-Hb) concentrations declined rapidly after storage of fresh venous blood and that hypoxic vasodilation by banked RBCs correlated strongly with the amounts of SNO-Hb (r(2) = 0.90; P < 0.0005). Renitrosylation of banked blood during storage increased the SNO-Hb content and restored its vasodilatory activity. In addition, canine coronary blood flow was greater during infusion of renitrosylated RBCs than during infusion of S-nitrosothiol-depleted RBCs, and this difference in coronary flow was accentuated by hypoxemia (P < 0.001). Our findings indicate that NO bioactivity is depleted in banked blood, impairing the vasodilatory response to hypoxia, and they suggest that SNO-Hb repletion may improve transfusion efficacy.
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Affiliation(s)
- James D Reynolds
- Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
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Abstract
Recent studies have underscored questions about the balance of risk and benefit of RBC transfusion. A better understanding of the nature and timing of molecular and functional changes in stored RBCs may provide strategies to improve the balance of benefit and risk of RBC transfusion. We analyzed changes occurring during RBC storage focusing on RBC deformability, RBC-dependent vasoregulatory function, and S-nitrosohemoglobin (SNO-Hb), through which hemoglobin (Hb) O(2) desaturation is coupled to regional increases in blood flow in vivo (hypoxic vasodilation). Five hundred ml of blood from each of 15 healthy volunteers was processed into leukofiltered, additive solution 3-exposed RBCs and stored at 1-6 degrees C according to AABB standards. Blood was subjected to 26 assays at 0, 3, 8, 24 and 96 h, and at 1, 2, 3, 4, and 6 weeks. RBC SNO-Hb decreased rapidly (1.2 x 10(-4) at 3 h vs. 6.5 x 10(-4) (fresh) mol S-nitrosothiol (SNO)/mol Hb tetramer (P = 0.032, mercuric-displaced photolysis-chemiluminescence assay), and remained low over the 42-day period. The decline was corroborated by using the carbon monoxide-saturated copper-cysteine assay [3.0 x 10(-5) at 3 h vs. 9.0 x 10(-5) (fresh) mol SNO/mol Hb]. In parallel, vasodilation by stored RBCs was significantly depressed. RBC deformability assayed at a physiological shear stress decreased gradually over the 42-day period (P < 0.001). Time courses vary for several storage-induced defects that might account for recent observations linking blood transfusion with adverse outcomes. Of clinical concern is that SNO levels, and their physiological correlate, RBC-dependent vasodilation, become depressed soon after collection, suggesting that even "fresh" blood may have developed adverse biological characteristics.
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