1
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Meliambro K, He JC, Campbell KN. Podocyte-targeted therapies - progress and future directions. Nat Rev Nephrol 2024; 20:643-658. [PMID: 38724717 DOI: 10.1038/s41581-024-00843-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/19/2024] [Indexed: 09/14/2024]
Abstract
Podocytes are the key target cells for injury across the spectrum of primary and secondary proteinuric kidney disorders, which account for up to 90% of cases of kidney failure worldwide. Seminal experimental and clinical studies have established a causative link between podocyte depletion and the magnitude of proteinuria in progressive glomerular disease. However, no substantial advances have been made in glomerular disease therapies, and the standard of care for podocytopathies relies on repurposed immunosuppressive drugs. The past two decades have seen a remarkable expansion in understanding of the mechanistic basis of podocyte injury, with prospects increasing for precision-based treatment approaches. Dozens of disease-causing genes with roles in the pathogenesis of clinical podocytopathies have been identified, as well as a number of putative glomerular permeability factors. These achievements, together with the identification of novel targets of podocyte injury, the development of potential approaches to harness the endogenous podocyte regenerative potential of progenitor cell populations, ongoing clinical trials of podocyte-specific pharmacological agents and the development of podocyte-directed drug delivery systems, contribute to an optimistic outlook for the future of glomerular disease therapy.
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Affiliation(s)
- Kristin Meliambro
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - John C He
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kirk N Campbell
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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2
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Scurt FG, Bose K, Mertens PR, Chatzikyrkou C, Herzog C. Cardiac Surgery-Associated Acute Kidney Injury. KIDNEY360 2024; 5:909-926. [PMID: 38689404 PMCID: PMC11219121 DOI: 10.34067/kid.0000000000000466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
AKI is a common and serious complication of cardiac surgery that has a significant impact on patient morbidity and mortality. The Kidney Disease Improving Global Outcomes definition of AKI is widely used to classify and identify AKI associated with cardiac surgery (cardiac surgery-associated AKI [CSA-AKI]) on the basis of changes in serum creatinine and/or urine output. There are various preoperative, intraoperative, and postoperative risk factors for the development of CSA-AKI which should be recognized and addressed as early as possible to expedite its diagnosis, reduce its occurrence, and prevent or ameliorate its devastating complications. Crucial issues are the inaccuracy of serum creatinine as a surrogate parameter of kidney function in the perioperative setting of cardiothoracic surgery and the necessity to discover more representative markers of the pathophysiology of AKI. However, except for the tissue inhibitor of metalloproteinase-2 and insulin-like growth factor binding protein 7 ratio, other diagnostic biomarkers with an acceptable sensitivity and specificity are still lacking. This article provides a comprehensive review of various aspects of CSA-AKI, including pathogenesis, risk factors, diagnosis, biomarkers, classification, prevention, and treatment management.
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Affiliation(s)
- Florian G. Scurt
- Clinic of Nephrology, Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Katrin Bose
- Department of Gastroenterology, Hepatology and Infectious Diseases, University Hospital Magdeburg, Magdeburg, Germany
| | - Peter R. Mertens
- Clinic of Nephrology, Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Christos Chatzikyrkou
- Department of Nephrology and Hypertension, Hannover Medical School, Hannover, Germany
| | - Carolin Herzog
- Clinic of Nephrology, Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
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3
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Greite R, Schott S, Wang L, Gohlke L, Kreimann K, Derlin K, Gutberlet M, Schmidbauer M, Leffler A, Tudorache I, Salman J, Ius F, Natanov R, Fegbeutel C, Haverich A, Lichtinghagen R, Hüsing AM, von Vietinghoff S, Schmitt R, Shushakova N, Rong S, Haller H, Schmidt‐Ott KM, Gram M, Vijayan V, Scheffner I, Gwinner W, Immenschuh S. Free heme and hemopexin in acute kidney injury after cardiopulmonary bypass and transient renal ischemia. Clin Transl Sci 2023; 16:2729-2743. [PMID: 37899696 PMCID: PMC10719480 DOI: 10.1111/cts.13667] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/13/2023] [Accepted: 10/09/2023] [Indexed: 10/31/2023] Open
Abstract
Free heme is released from hemoproteins during hemolysis or ischemia reperfusion injury and can be pro-inflammatory. Most studies on nephrotoxicity of hemolysis-derived proteins focus on free hemoglobin (fHb) with heme as a prosthetic group. Measurement of heme in its free, non-protein bound, form is challenging and not commonly used in clinical routine diagnostics. In contrast to fHb, the role of free heme in acute kidney injury (AKI) after cardiopulmonary bypass (CPB) surgery is unknown. Using an apo-horseradish peroxidase-based assay, we identified free heme during CPB surgery as predictor of AKI in patients undergoing cardiac valve replacement (n = 37). Free heme levels during CPB surgery correlated with depletion of hemopexin (Hx), a heme scavenger-protein. In mice, the impact of high levels of circulating free heme on the development of AKI following transient renal ischemia and the therapeutic potential of Hx were investigated. C57BL/6 mice were subjected to bilateral renal ischemia/reperfusion injury for 15 min which did not cause AKI. However, additional administration of free heme in this model promoted overt AKI with reduced renal function, increased renal inflammation, and reduced renal perfusion on functional magnetic resonance imaging. Hx treatment attenuated AKI. Free heme administration to sham operated control mice did not cause AKI. In conclusion, free heme is a predictor of AKI in CPB surgery patients and promotes AKI in transient renal ischemia. Depletion of Hx in CPB surgery patients and attenuation of AKI by Hx in the in vivo model encourage further research on Hx therapy in patients with increased free heme levels during CPB surgery.
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Affiliation(s)
- Robert Greite
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Sebastian Schott
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Li Wang
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Lukas Gohlke
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Kirill Kreimann
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Katja Derlin
- Institute for Diagnostic and Interventional RadiologyHannover Medical SchoolHannoverGermany
| | - Marcel Gutberlet
- Institute for Diagnostic and Interventional RadiologyHannover Medical SchoolHannoverGermany
| | - Martina Schmidbauer
- Institute for Diagnostic and Interventional RadiologyHannover Medical SchoolHannoverGermany
| | - Andreas Leffler
- Department of Anesthesiology and Intensive Care MedicineHannover Medical SchoolHannoverGermany
| | - Igor Tudorache
- Department of Cardiac SurgeryUniversity Hospital DusseldorfDusseldorfGermany
| | - Jawad Salman
- Department of Cardiothoracic, Transplantation and Vascular SurgeryHannover Medical SchoolHannoverGermany
| | - Fabio Ius
- Department of Cardiothoracic, Transplantation and Vascular SurgeryHannover Medical SchoolHannoverGermany
| | - Ruslan Natanov
- Department of Cardiothoracic, Transplantation and Vascular SurgeryHannover Medical SchoolHannoverGermany
| | - Christine Fegbeutel
- Department of Cardiothoracic, Transplantation and Vascular SurgeryHannover Medical SchoolHannoverGermany
| | - Axel Haverich
- Department of Cardiothoracic, Transplantation and Vascular SurgeryHannover Medical SchoolHannoverGermany
| | | | - Anne M. Hüsing
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Sibylle von Vietinghoff
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
- Nephrology Section, Medical Clinic 1University Hospital BonnBonnGermany
| | - Roland Schmitt
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Nelli Shushakova
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Song Rong
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Hermann Haller
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Kai M. Schmidt‐Ott
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Magnus Gram
- Pediatrics, Department of Clinical Sciences LundSkane University Hospital, Lund UniversityLundSweden
| | - Vijith Vijayan
- Institute for Transfusion Medicine and Transplant EngineeringHannover Medical SchoolHannoverGermany
- Division of Critical Care Medicine, Department of PediatricsStanford University School of MedicineStanfordCaliforniaUSA
| | - Irina Scheffner
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Wilfried Gwinner
- Department of Nephrology and HypertensionHannover Medical SchoolHannoverGermany
| | - Stephan Immenschuh
- Institute for Transfusion Medicine and Transplant EngineeringHannover Medical SchoolHannoverGermany
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4
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Golshayan D, Schwotzer N, Fakhouri F, Zuber J. Targeting the Complement Pathway in Kidney Transplantation. J Am Soc Nephrol 2023; 34:1776-1792. [PMID: 37439664 PMCID: PMC10631604 DOI: 10.1681/asn.0000000000000192] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 07/02/2023] [Indexed: 07/14/2023] Open
Abstract
The complement system is paramount in the clearance of pathogens and cell debris, yet is increasingly recognized as a key component in several pathways leading to allograft injury. There is thus a growing interest in new biomarkers to assess complement activation and guide tailored therapies after kidney transplantation (KTx). C5 blockade has revolutionized post-transplant management of atypical hemolytic uremic syndrome, a paradigm of complement-driven disease. Similarly, new drugs targeting the complement amplification loop hold much promise in the treatment and prevention of recurrence of C3 glomerulopathy. Although unduly activation of the complement pathway has been described after brain death and ischemia reperfusion, any clinical attempts to mitigate the ensuing renal insults have so far provided mixed results. However, the intervention timing, strategy, and type of complement blocker need to be optimized in these settings. Furthermore, the fast-moving field of ex vivo organ perfusion technology opens new avenues to deliver complement-targeted drugs to kidney allografts with limited iatrogenic risks. Complement plays also a key role in the pathogenesis of donor-specific ABO- and HLA-targeted alloantibodies. However, C5 blockade failed overall to improve outcomes in highly sensitized patients and prevent the progression to chronic antibody-mediated rejection (ABMR). Similarly, well-conducted studies with C1 inhibitors in sensitized recipients yielded disappointing results so far, in part, because of subtherapeutic dosage used in clinical studies. The emergence of new complement blockers raises hope to significantly reduce the negative effect of ischemia reperfusion, ABMR, and nephropathy recurrence on outcomes after KTx.
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Affiliation(s)
- Dela Golshayan
- Transplantation Center, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Nora Schwotzer
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Fadi Fakhouri
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Julien Zuber
- Service de Transplantation rénale adulte, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, Paris, France
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5
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De Simone G, Varricchio R, Ruberto TF, di Masi A, Ascenzi P. Heme Scavenging and Delivery: The Role of Human Serum Albumin. Biomolecules 2023; 13:biom13030575. [PMID: 36979511 PMCID: PMC10046553 DOI: 10.3390/biom13030575] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/10/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
Heme is the reactive center of several metal-based proteins that are involved in multiple biological processes. However, free heme, defined as the labile heme pool, has toxic properties that are derived from its hydrophobic nature and the Fe-atom. Therefore, the heme concentration must be tightly controlled to maintain cellular homeostasis and to avoid pathological conditions. Therefore, different systems have been developed to scavenge either Hb (i.e., haptoglobin (Hp)) or the free heme (i.e., high-density lipoproteins (HDL), low-density lipoproteins (LDL), hemopexin (Hx), and human serum albumin (HSA)). In the first seconds after heme appearance in the plasma, more than 80% of the heme binds to HDL and LDL, and only the remaining 20% binds to Hx and HSA. Then, HSA slowly removes most of the heme from HDL and LDL, and finally, heme transits to Hx, which releases it into hepatic parenchymal cells. The Hx:heme or HSA:heme complexes are internalized via endocytosis mediated by the CD91 and CD71 receptors, respectively. As heme constitutes a major iron source for pathogens, bacteria have evolved hemophores that can extract and uptake heme from host proteins, including HSA:heme. Here, the molecular mechanisms underlying heme scavenging and delivery from HSA are reviewed. Moreover, the relevance of HSA in disease states associated with increased heme plasma concentrations are discussed.
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Affiliation(s)
- Giovanna De Simone
- Department of Sciences, Section of Biomedical Sciences and Technologies, Roma Tre University, 00146 Roma, Italy
| | - Romualdo Varricchio
- Department of Sciences, Section of Biomedical Sciences and Technologies, Roma Tre University, 00146 Roma, Italy
| | - Tommaso Francesco Ruberto
- Department of Sciences, Section of Biomedical Sciences and Technologies, Roma Tre University, 00146 Roma, Italy
| | - Alessandra di Masi
- Department of Sciences, Section of Biomedical Sciences and Technologies, Roma Tre University, 00146 Roma, Italy
- Centro Linceo Interdisciplinare Beniamino Segre, Accademia Nazionale dei Lincei, 00165 Roma, Italy
| | - Paolo Ascenzi
- Department of Sciences, Section of Biomedical Sciences and Technologies, Roma Tre University, 00146 Roma, Italy
- Accademia Nazionale dei Lincei, 00165 Roma, Italy
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6
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Fan X, Zhang X, Liu LC, Zhang S, Pelger CB, Lughmani HY, Haller ST, Gunning WT, Cooper CJ, Gong R, Dworkin LD, Gupta R. Hemopexin accumulates in kidneys and worsens acute kidney injury by causing hemoglobin deposition and exacerbation of iron toxicity in proximal tubules. Kidney Int 2022; 102:1320-1330. [PMID: 36007598 DOI: 10.1016/j.kint.2022.07.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 06/29/2022] [Accepted: 07/11/2022] [Indexed: 01/12/2023]
Abstract
Hemopexin, a heme scavenging protein, accumulates in the kidneys during acute kidney injury (AKI). However, the function of this accumulated hemopexin in the kidney is unclear. In both the cisplatin-induced and the unilateral kidney ischemia-reperfusion injury models of AKI, we found accumulation of hemoglobin and hemopexin in the kidneys localized to the proximal tubules. Next, hemopexin wild-type and knockout mice were compared in both AKI models and hemopexin wild type mice had significantly worse kidney injury. Furthermore, there was increased kidney expression of kidney injury molecule-1 (a biomarker of AKI) and heme oxygenase-1 (an indicator of oxidative stress) in hemopexin wild type compared with knockout mice in both models of AKI. Next, the interaction of hemopexin and hemoglobin in vitro was investigated using cultured proximal tubular cells. Co-incubation of hemopexin with hemoglobin resulted in hemoglobin deposition and exaggerated hemoglobin-induced injury. Deferoxamine, an iron chelator, and ferrostatin-1, a ferroptosis inhibitor, inhibited this deleterious effect of hemoglobin and hemopexin in proximal tubular cells, implicating iron toxicity in the mechanism of hemopexin mediated injury. Furthermore, the protective effect of deferoxamine in cisplatin-induced AKI was apparent in hemopexin wild type, but not in hemopexin knockout mice, further implicating hemopexin as a mediator of iron toxicity in AKI. Thus, our findings demonstrate that hemopexin accumulates in the kidneys and worsens kidney injury in AKI by increasing hemoglobin deposition on proximal tubular cells to exaggerate hemoglobin-induced cell injury.
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Affiliation(s)
- Xiaoming Fan
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Xiaolu Zhang
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Lijun C Liu
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Shungang Zhang
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Cole B Pelger
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Haroon Y Lughmani
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Steven T Haller
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - William T Gunning
- Department of Pathology, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Christopher J Cooper
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Rujun Gong
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Lance D Dworkin
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Rajesh Gupta
- Department of Medicine, University of Toledo College of Medicine, Toledo, Ohio, USA.
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7
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Vijayan V, Greite R, Schott S, Doricic J, Madyaningrana K, Pradhan P, Martens J, Blasczyk R, Janciauskiene S, Immenschuh S. Determination of free heme in stored red blood cells with an apo-horseradish peroxidase-based assay. Biol Chem 2022; 403:1091-1098. [PMID: 36054292 DOI: 10.1515/hsz-2022-0184] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/15/2022] [Indexed: 12/19/2022]
Abstract
Transfusion effectiveness of red blood cells (RBCs) has been associated with duration of the storage period. Storage-dependent RBC alterations lead to hemolysis and release of toxic free heme, but the increase of free heme levels over time is largely unknown. In the current study, an apo-horseradish peroxidase (apoHRP)-based assay was applied to measure levels of free heme at regular intervals or periodically in supernatants of RBCs until a maximum storage period of 42 days. Free heme levels increased with linear time-dependent kinetics up to day 21 and accelerated disproportionally after day 28 until day 42, as determined with the apoHRP assay. Individual time courses of free heme in different RBC units exhibited high variability. Notably, levels of free hemoglobin, an established indicator of RBC damage, and those of total heme increased with continuous time-dependent linear kinetics over the entire 42 day storage period, respectively. Supernatants from RBC units with high levels of free heme led to inflammatory activation of human neutrophils. In conclusion, determining free heme in stored RBCs with the applied apoHRP assay may become feasible for testing of RBC storage quality in clinical transfusion medicine.
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Affiliation(s)
- Vijith Vijayan
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Robert Greite
- Department of Nephrology, Hannover Medical School, D-30625 Hannover, Germany
| | - Sebastian Schott
- Department of Nephrology, Hannover Medical School, D-30625 Hannover, Germany
| | - Julian Doricic
- Department of Nephrology, Hannover Medical School, D-30625 Hannover, Germany
| | - Kukuh Madyaningrana
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.,Faculty of Biotechnology, Universitas Kristen Duta Wacana, 55224 Yogyakarta, Indonesia
| | - Pooja Pradhan
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Jörg Martens
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | - Rainer Blasczyk
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
| | | | - Stephan Immenschuh
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany
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8
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Greite R, Wang L, Gohlke L, Schott S, Kreimann K, Doricic J, Leffler A, Tudorache I, Salman J, Natanov R, Ius F, Fegbeutel C, Haverich A, Lichtinghagen R, Chen R, Rong S, Haller H, Vijayan V, Gram M, Scheffner I, Gueler F, Gwinner W, Immenschuh S. Cell-Free Hemoglobin in Acute Kidney Injury after Lung Transplantation and Experimental Renal Ischemia/Reperfusion. Int J Mol Sci 2022; 23:ijms232113272. [PMID: 36362059 PMCID: PMC9657083 DOI: 10.3390/ijms232113272] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 10/15/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022] Open
Abstract
Cell-free hemoglobin (CFH), a pro-oxidant and cytotoxic compound that is released in hemolysis, has been associated with nephrotoxicity. Lung transplantation (LuTx) is a clinical condition with a high incidence of acute kidney injury (AKI). In this study, we investigated the plasma levels of CFH and haptoglobin, a CFH-binding serum protein, in prospectively enrolled LuTx patients (n = 20) with and without AKI. LuTx patients with postoperative AKI had higher CFH plasma levels at the end of surgery compared with no-AKI patients, and CFH correlated with serum creatinine at 48 h. Moreover, CFH levels inversely correlated with haptoglobin levels, which were significantly reduced at the end of surgery in LuTx patients with AKI. Because multiple other factors can contribute to AKI development in the complex clinical setting of LuTx, we next investigated the role of exogenous CFH administration in a mouse model of mild bilateral renal ischemia reperfusion injury (IRI). Exogenous administration of CFH after reperfusion caused overt AKI with creatinine increase, tubular injury, and enhanced markers of renal inflammation compared with vehicle-treated animals. In conclusion, CFH is a possible factor contributing to postoperative AKI after LuTx and promotes AKI in an experimental model of mild transient renal ischemia. Targeting CFH might be a therapeutic option to prevent AKI after LuTx.
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Affiliation(s)
- Robert Greite
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
- Correspondence:
| | - Li Wang
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Lukas Gohlke
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Sebastian Schott
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Kirill Kreimann
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Julian Doricic
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Andreas Leffler
- Anaesthesiology, Hannover Medical School, 30625 Hannover, Germany
| | - Igor Tudorache
- Cardiac Surgery, University of Dusseldorf, 40225 Dusseldorf, Germany
| | - Jawad Salman
- Cardiac Surgery, Hannover Medical School, 30625 Hannover, Germany
| | - Ruslan Natanov
- Cardiac Surgery, Hannover Medical School, 30625 Hannover, Germany
| | - Fabio Ius
- Cardiac Surgery, Hannover Medical School, 30625 Hannover, Germany
- German Center for Lung Research (DZL), 35392 Giessen, Germany
| | | | - Axel Haverich
- Cardiac Surgery, Hannover Medical School, 30625 Hannover, Germany
| | | | - Rongjun Chen
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Song Rong
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Hermann Haller
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Vijith Vijayan
- Pediatrics, Stanford University, Stanford, CA 94305, USA
| | - Magnus Gram
- Department of Pediatrics, Clinical Sciences Lund, Lund University, 22220 Lund, Sweden
| | - Irina Scheffner
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Faikah Gueler
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Wilfried Gwinner
- Department of Nephrology and Hypertension, Hannover Medical School, 30625 Hannover, Germany
| | - Stephan Immenschuh
- Institute of Transfusion Medicine and Transplant Engineering, Hannover Medical School, 30625 Hannover, Germany
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9
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Fleig S, Kapanadze T, Bernier-Latmani J, Lill JK, Wyss T, Gamrekelashvili J, Kijas D, Liu B, Hüsing AM, Bovay E, Jirmo AC, Halle S, Ricke-Hoch M, Adams RH, Engel DR, von Vietinghoff S, Förster R, Hilfiker-Kleiner D, Haller H, Petrova TV, Limbourg FP. Loss of vascular endothelial notch signaling promotes spontaneous formation of tertiary lymphoid structures. Nat Commun 2022; 13:2022. [PMID: 35440634 PMCID: PMC9018798 DOI: 10.1038/s41467-022-29701-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 03/21/2022] [Indexed: 12/20/2022] Open
Abstract
Tertiary lymphoid structures (TLS) are lymph node-like immune cell clusters that emerge during chronic inflammation in non-lymphoid organs like the kidney, but their origin remains not well understood. Here we show, using conditional deletion strategies of the canonical Notch signaling mediator Rbpj, that loss of endothelial Notch signaling in adult mice induces the spontaneous formation of bona fide TLS in the kidney, liver and lung, based on molecular, cellular and structural criteria. These TLS form in a stereotypical manner around parenchymal arteries, while secondary lymphoid structures remained largely unchanged. This effect is mediated by endothelium of blood vessels, but not lymphatics, since a lymphatic endothelial-specific targeting strategy did not result in TLS formation, and involves loss of arterial specification and concomitant acquisition of a high endothelial cell phenotype, as shown by transcriptional analysis of kidney endothelial cells. This indicates a so far unrecognized role for vascular endothelial cells and Notch signaling in TLS initiation. Loss of canonical Notch signaling in vascular endothelial cells induces spontaneous formation of proto-typical tertiary lymphoid structures in mouse kidney, liver and lungs, which form around central arteries that acquire a high endothelial cell signature
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Affiliation(s)
- Susanne Fleig
- Vascular Medicine Research, Hannover Medical School, 30625, Hannover, Germany.,Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany.,Department of Geriatric Medicine (Medical Clinic VI), RWTH Aachen University Hospital, 52074, Aachen, Germany
| | - Tamar Kapanadze
- Vascular Medicine Research, Hannover Medical School, 30625, Hannover, Germany.,Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany
| | - Jeremiah Bernier-Latmani
- Vascular and Tumor Biology Laboratory, Department of Oncology UNIL CHUV and Ludwig Institute for Cancer Research, Lausanne, Switzerland
| | - Julia K Lill
- Department of Immunodynamics, Institute for Experimental Immunology and Imaging, Medical Research Centre, University Hospital Essen, 45147, Essen, Germany
| | - Tania Wyss
- Vascular and Tumor Biology Laboratory, Department of Oncology UNIL CHUV and Ludwig Institute for Cancer Research, Lausanne, Switzerland.,SIB Swiss Institute of Bioinformatics, Lausanne, 1015, Switzerland
| | - Jaba Gamrekelashvili
- Vascular Medicine Research, Hannover Medical School, 30625, Hannover, Germany.,Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany
| | - Dustin Kijas
- Vascular Medicine Research, Hannover Medical School, 30625, Hannover, Germany.,Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany
| | - Bin Liu
- Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany
| | - Anne M Hüsing
- Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany
| | - Esther Bovay
- Max-Planck-Institute for Molecular Biomedicine, 48149, Muenster, Germany
| | - Adan Chari Jirmo
- Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany.,Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Stephan Halle
- Institute of Immunology, Hannover Medical School, 30625, Hannover, Germany
| | - Melanie Ricke-Hoch
- Department of Cardiology and Angiology, Hannover Medical School, 30625, Hannover, Germany
| | - Ralf H Adams
- Max-Planck-Institute for Molecular Biomedicine, 48149, Muenster, Germany
| | - Daniel R Engel
- Department of Immunodynamics, Institute for Experimental Immunology and Imaging, Medical Research Centre, University Hospital Essen, 45147, Essen, Germany
| | - Sibylle von Vietinghoff
- Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany.,Division of Medicine I, Nephrology section, UKB Bonn University Hospital, Bonn, Germany
| | - Reinhold Förster
- Institute of Immunology, Hannover Medical School, 30625, Hannover, Germany
| | - Denise Hilfiker-Kleiner
- Department of Cardiology and Angiology, Hannover Medical School, 30625, Hannover, Germany.,Department of Cardiovascular Complications of Oncologic Therapies, Medical Faculty of the Philipps University Marburg, 35037, Marburg, Germany
| | - Hermann Haller
- Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany
| | - Tatiana V Petrova
- Vascular and Tumor Biology Laboratory, Department of Oncology UNIL CHUV and Ludwig Institute for Cancer Research, Lausanne, Switzerland
| | - Florian P Limbourg
- Vascular Medicine Research, Hannover Medical School, 30625, Hannover, Germany. .,Department of Nephrology and Hypertension, Hannover Medical School, 30625, Hannover, Germany.
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10
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Sevoflurane Dampens Acute Pulmonary Inflammation via the Adenosine Receptor A2B and Heme Oxygenase-1. Cells 2022; 11:cells11071094. [PMID: 35406657 PMCID: PMC8997763 DOI: 10.3390/cells11071094] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/20/2022] [Accepted: 03/22/2022] [Indexed: 11/17/2022] Open
Abstract
Acute respiratory distress syndrome is a life-threatening disease associated with high mortality. The adenosine receptor A2B (Adora2b) provides anti-inflammatory effects, which are also associated with the intracellular enzyme heme oxygenase-1 (HO-1). Our study determined the mechanism of sevoflurane’s protective properties and investigated the link between sevoflurane and the impact of a functional Adora2b via HO-1 modulation during lipopolysaccharide (LPS)-induced lung injury. We examined the LPS-induced infiltration of polymorphonuclear neutrophils (PMNs) into the lung tissue and protein extravasation in wild-type and Adora2b−/− animals. We generated chimeric animals, to identify the impact of sevoflurane on Adora2b of hematopoietic and non-hematopoietic cells. Sevoflurane decreased the LPS-induced PMN-infiltration and diminished the edema formation in wild-type mice. Reduced PMN counts after sevoflurane treatment were detected only in chimeric mice, which expressed Adora2b exclusively on leukocytes. The Adora2b on hematopoietic and non-hematopoietic cells was required to improve the permeability after sevoflurane inhalation. Further, sevoflurane increased the protective effects of HO-1 modulation on PMN migration and microvascular permeability. These protective effects were abrogated by specific HO-1 inhibition. In conclusion, our data revealed new insights into the protective mechanisms of sevoflurane application during acute pulmonary inflammation and the link between sevoflurane and Adora2b, and HO-1 signaling, respectively.
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11
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Heme Oxygenase-1: An Anti-Inflammatory Effector in Cardiovascular, Lung, and Related Metabolic Disorders. Antioxidants (Basel) 2022; 11:antiox11030555. [PMID: 35326205 PMCID: PMC8944973 DOI: 10.3390/antiox11030555] [Citation(s) in RCA: 78] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/24/2022] [Accepted: 03/10/2022] [Indexed: 12/12/2022] Open
Abstract
The heme oxygenase (HO) enzyme system catabolizes heme to carbon monoxide (CO), ferrous iron, and biliverdin-IXα (BV), which is reduced to bilirubin-IXα (BR) by biliverdin reductase (BVR). HO activity is represented by two distinct isozymes, the inducible form, HO-1, and a constitutive form, HO-2, encoded by distinct genes (HMOX1, HMOX2, respectively). HO-1 responds to transcriptional activation in response to a wide variety of chemical and physical stimuli, including its natural substrate heme, oxidants, and phytochemical antioxidants. The expression of HO-1 is regulated by NF-E2-related factor-2 and counter-regulated by Bach-1, in a heme-sensitive manner. Additionally, HMOX1 promoter polymorphisms have been associated with human disease. The induction of HO-1 can confer protection in inflammatory conditions through removal of heme, a pro-oxidant and potential catalyst of lipid peroxidation, whereas iron released from HO activity may trigger ferritin synthesis or ferroptosis. The production of heme-derived reaction products (i.e., BV, BR) may contribute to HO-dependent cytoprotection via antioxidant and immunomodulatory effects. Additionally, BVR and BR have newly recognized roles in lipid regulation. CO may alter mitochondrial function leading to modulation of downstream signaling pathways that culminate in anti-apoptotic, anti-inflammatory, anti-proliferative and immunomodulatory effects. This review will present evidence for beneficial effects of HO-1 and its reaction products in human diseases, including cardiovascular disease (CVD), metabolic conditions, including diabetes and obesity, as well as acute and chronic diseases of the liver, kidney, or lung. Strategies targeting the HO-1 pathway, including genetic or chemical modulation of HO-1 expression, or application of BR, CO gas, or CO donor compounds show therapeutic potential in inflammatory conditions, including organ ischemia/reperfusion injury. Evidence from human studies indicate that HO-1 expression may represent a biomarker of oxidative stress in various clinical conditions, while increases in serum BR levels have been correlated inversely to risk of CVD and metabolic disease. Ongoing human clinical trials investigate the potential of CO as a therapeutic in human disease.
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12
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Qi R, Qin W. Role of Complement System in Kidney Transplantation: Stepping From Animal Models to Clinical Application. Front Immunol 2022; 13:811696. [PMID: 35281019 PMCID: PMC8913494 DOI: 10.3389/fimmu.2022.811696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 01/31/2022] [Indexed: 12/23/2022] Open
Abstract
Kidney transplantation is a life-saving strategy for patients with end-stage renal diseases. Despite the advances in surgical techniques and immunosuppressive agents, the long-term graft survival remains a challenge. Growing evidence has shown that the complement system, part of the innate immune response, is involved in kidney transplantation. Novel insights highlighted the role of the locally produced and intracellular complement components in the development of inflammation and the alloreactive response in the kidney allograft. In the current review, we provide the updated understanding of the complement system in kidney transplantation. We will discuss the involvement of the different complement components in kidney ischemia-reperfusion injury, delayed graft function, allograft rejection, and chronic allograft injury. We will also introduce the existing and upcoming attempts to improve allograft outcomes in animal models and in the clinical setting by targeting the complement system.
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Affiliation(s)
| | - Weijun Qin
- Department of Urology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
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13
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Modeling oxidative injury response in human kidney organoids. Stem Cell Res Ther 2022; 13:76. [PMID: 35189973 PMCID: PMC8862571 DOI: 10.1186/s13287-022-02752-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 02/08/2022] [Indexed: 02/06/2023] Open
Abstract
Abstract
Background
Hemolysis occurs in many injury settings and can trigger disease processes. In the kidney, extracellular hemoglobin can induce damage via several mechanisms. These include oxidative stress, mitochondrial dysfunction, and inflammation, which promote fibrosis and chronic kidney disease. Understanding the pathophysiology of these injury pathways offers opportunities to develop new therapeutic strategies.
Methods
To model hemolysis-induced kidney injury, human kidney organoids were treated with hemin, an iron-containing porphyrin, that generates reactive oxygen species. In addition, we developed an induced pluripotent stem cell line expressing the biosensor, CytochromeC-GFP (CytoC-GFP), which provides a real-time readout of mitochondrial morphology, health, and early apoptotic events.
Results
We found that hemin-treated kidney organoids show oxidative damage, increased expression of injury markers, impaired functionality of organic anion and cation transport and undergo fibrosis. Injury could be detected in live CytoC-GFP organoids by cytoplasmic localization of fluorescence. Finally, we show that 4-(phenylthio)butanoic acid, an HDAC inhibitor with anti-fibrotic effects in vivo, reduces hemin-induced human kidney organoid fibrosis.
Conclusion
This work establishes a hemin-induced model of kidney organoid injury. This platform provides a new tool to study the injury and repair response pathways in human kidney tissue and will assist in the development of new therapeutics.
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14
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Zhang Y, Zuo X. miR-25-3p protects renal tubular epithelial cells from apoptosis induced by renal IRI by targeting DKK3. Open Life Sci 2022; 16:1393-1404. [PMID: 35174294 PMCID: PMC8812715 DOI: 10.1515/biol-2021-0127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/10/2021] [Accepted: 10/20/2021] [Indexed: 11/15/2022] Open
Abstract
Renal ischemia-reperfusion injury (IRI) is one of the main causes of acute kidney injury (AKI). So far, there have been many studies on renal IRI, although an effective treatment method has not been developed. In recent years, growing evidence has shown that small noncoding RNAs play an important regulatory role in renal IRI. This article aims to explore whether microRNA-25-3p (miR-25-3p) plays a role in the molecular mechanism of renal IRI. The results showed that the expression level of miR-25-3p was significantly downregulated in a rat renal IRI model, and this result was confirmed with in vitro experiments. After the hypoxia-reoxygenation treatment, the apoptosis level of NRK-52E cells transfected with miR-25-3p mimics decreased significantly, and this antiapoptotic effect was antagonized by miR-25-3p inhibitors. In addition, we confirmed that DKK3 is a target of miR-25-3p. miR-25-3p exerts its protective effect against apoptosis on NRK-52E cells by inhibiting the expression of DKK3, and downregulating the expression level of miR-25-3p could disrupt this protective effect. In addition, we reconfirmed the role of miR-25-3p in rats. Therefore, we confirmed that miR-25-3p may target DKK3 to reduce renal cell damage caused by hypoxia and that miR-25-3p may be a new potential treatment for renal IRI.
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Affiliation(s)
- Yu Zhang
- Department of Pharmacology, Nanjing Medical University, Nanjing 210000, Jiangsu Province, P. R. China
| | - Xiangrong Zuo
- Department of Intensive Care Medical, Jiangsu Provincial People's Hospital, Nanjing 210000, Jiangsu Province, P. R. China
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15
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Gallio A, Fung SSP, Cammack-Najera A, Hudson AJ, Raven EL. Understanding the Logistics for the Distribution of Heme in Cells. JACS AU 2021; 1:1541-1555. [PMID: 34723258 PMCID: PMC8549057 DOI: 10.1021/jacsau.1c00288] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Indexed: 05/03/2023]
Abstract
Heme is essential for the survival of virtually all living systems-from bacteria, fungi, and yeast, through plants to animals. No eukaryote has been identified that can survive without heme. There are thousands of different proteins that require heme in order to function properly, and these are responsible for processes such as oxygen transport, electron transfer, oxidative stress response, respiration, and catalysis. Further to this, in the past few years, heme has been shown to have an important regulatory role in cells, in processes such as transcription, regulation of the circadian clock, and the gating of ion channels. To act in a regulatory capacity, heme needs to move from its place of synthesis (in mitochondria) to other locations in cells. But while there is detailed information on how the heme lifecycle begins (heme synthesis), and how it ends (heme degradation), what happens in between is largely a mystery. Here we summarize recent information on the quantification of heme in cells, and we present a discussion of a mechanistic framework that could meet the logistical challenge of heme distribution.
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Affiliation(s)
- Andrea
E. Gallio
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
| | - Simon S.-P. Fung
- Department
of Chemistry and Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester LE1 7RH, U.K.
| | - Ana Cammack-Najera
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
| | - Andrew J. Hudson
- Department
of Chemistry and Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester LE1 7RH, U.K.
| | - Emma L. Raven
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
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16
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Li Y, Ma K, Han Z, Chi M, Sai X, Zhu P, Ding Z, Song L, Liu C. Immunomodulatory Effects of Heme Oxygenase-1 in Kidney Disease. Front Med (Lausanne) 2021; 8:708453. [PMID: 34504854 PMCID: PMC8421649 DOI: 10.3389/fmed.2021.708453] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 07/31/2021] [Indexed: 01/23/2023] Open
Abstract
Kidney disease is a general term for heterogeneous damage that affects the function and the structure of the kidneys. The rising incidence of kidney diseases represents a considerable burden on the healthcare system, so the development of new drugs and the identification of novel therapeutic targets are urgently needed. The pathophysiology of kidney diseases is complex and involves multiple processes, including inflammation, autophagy, cell-cycle progression, and oxidative stress. Heme oxygenase-1 (HO-1), an enzyme involved in the process of heme degradation, has attracted widespread attention in recent years due to its cytoprotective properties. As an enzyme with known anti-oxidative functions, HO-1 plays an indispensable role in the regulation of oxidative stress and is involved in the pathogenesis of several kidney diseases. Moreover, current studies have revealed that HO-1 can affect cell proliferation, cell maturation, and other metabolic processes, thereby altering the function of immune cells. Many strategies, such as the administration of HO-1-overexpressing macrophages, use of phytochemicals, and carbon monoxide-based therapies, have been developed to target HO-1 in a variety of nephropathological animal models, indicating that HO-1 is a promising protein for the treatment of kidney diseases. Here, we briefly review the effects of HO-1 induction on specific immune cell populations with the aim of exploring the potential therapeutic roles of HO-1 and designing HO-1-based therapeutic strategies for the treatment of kidney diseases.
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Affiliation(s)
- Yunlong Li
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,School of Medical and Life Sciences, Reproductive and Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Kuai Ma
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Zhongyu Han
- School of Medical and Life Sciences, Reproductive and Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Mingxuan Chi
- School of Medical and Life Sciences, Reproductive and Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Xiyalatu Sai
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Ping Zhu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhaolun Ding
- Department of Emergency Surgery, Shannxi Provincial People's Hospital, Xi'an, China
| | - Linjiang Song
- School of Medical and Life Sciences, Reproductive and Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Chi Liu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,Department of Nephrology, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
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17
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Three-dimensional Reconstruction of Renal Vascular Tumor Anatomy to facilitate accurate preoperative planning of partial nephrectomy. Biomedicine (Taipei) 2021; 10:36-41. [PMID: 33854933 PMCID: PMC7735978 DOI: 10.37796/2211-8039.1078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 07/16/2020] [Indexed: 12/24/2022] Open
Abstract
Objectives To evaluate the role of three-dimensional (3D) reconstruction tumors and vessels of the kidneys in aiding the preoperative planning of partial nephrectomy. Materials and methods Patients with renal tumors to be treated with partial nephrectomy were included. Each patient underwent a preoperative computed tomography (CT) survey, and the reconstruction of each patient's 3D arteriography and 3D surface-rendered tumor was performed based on the CT images for preoperative surgical planning. Results A total of 6 patients, three with tumors of the right kidney and three with tumors of the left kidney, were enrolled in the study. The patients' mean age was 49.33 ± 4.03 years (range: 45-57 years), and their mean tumor size was 4.4 ± 1.84 cm (range: 2.2-6.8 cm). Four underwent robot-assisted laparoscopic partial nephrectomies, one underwent a traditional laparoscopic partial nephrectomy, and one underwent a radical nephrectomy through laparotomy. Their average postoperative hospital stay was 6.7 days (range: 3-10 days). No intraoperative or postoperative complications were noted. The renal function was preserved in all the patients, and none of the patients exhibited evidence of local recurrence during more than 6 years of follow-up. Conclusions 3D arteriography fused with 3D surface-rendered tumor image navigation facilitates precise preoperative planning.
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18
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Detzel MS, Schmalohr BF, Steinbock F, Hopp MT, Ramoji A, Paul George AA, Neugebauer U, Imhof D. Revisiting the interaction of heme with hemopexin. Biol Chem 2021; 402:675-691. [PMID: 33581700 DOI: 10.1515/hsz-2020-0347] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 02/06/2021] [Indexed: 12/23/2022]
Abstract
In hemolytic disorders, erythrocyte lysis results in massive release of hemoglobin and, subsequently, toxic heme. Hemopexin is the major protective factor against heme toxicity in human blood and currently considered for therapeutic use. It has been widely accepted that hemopexin binds heme with extraordinarily high affinity of <1 pM in a 1:1 ratio. However, several lines of evidence point to a higher stoichiometry and lower affinity than determined 50 years ago. Here, we re-analyzed these data. SPR and UV/Vis spectroscopy were used to monitor the interaction of heme with the human protein. The heme-binding sites of hemopexin were characterized using hemopexin-derived peptide models and competitive displacement assays. We obtained a K D value of 0.32 ± 0.04 nM and the ratio for the interaction was determined to be 1:1 at low heme concentrations and at least 2:1 (heme:hemopexin) at high concentrations. We were able to identify two yet unknown potential heme-binding sites on hemopexin. Furthermore, molecular modelling with a newly created homology model of human hemopexin suggested a possible recruiting mechanism by which heme could consecutively bind several histidine residues on its way into the binding pocket. Our findings have direct implications for the potential administration of hemopexin in hemolytic disorders.
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Affiliation(s)
- Milena Sophie Detzel
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121Bonn, Germany
| | - Benjamin Franz Schmalohr
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121Bonn, Germany
| | - Francèl Steinbock
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121Bonn, Germany
| | - Marie-Thérèse Hopp
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121Bonn, Germany
| | - Anuradha Ramoji
- Center for Sepsis Control and Care (CSCC), Jena University Hospital, D-07747Jena, Germany.,Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, D-07745Jena, Germany
| | - Ajay Abisheck Paul George
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121Bonn, Germany
| | - Ute Neugebauer
- Center for Sepsis Control and Care (CSCC), Jena University Hospital, D-07747Jena, Germany.,Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, D-07745Jena, Germany
| | - Diana Imhof
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121Bonn, Germany
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19
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Grunenwald A, Roumenina LT, Frimat M. Heme Oxygenase 1: A Defensive Mediator in Kidney Diseases. Int J Mol Sci 2021; 22:2009. [PMID: 33670516 PMCID: PMC7923026 DOI: 10.3390/ijms22042009] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 12/18/2022] Open
Abstract
The incidence of kidney disease is rising, constituting a significant burden on the healthcare system and making identification of new therapeutic targets increasingly urgent. The heme oxygenase (HO) system performs an important function in the regulation of oxidative stress and inflammation and, via these mechanisms, is thought to play a role in the prevention of non-specific injuries following acute renal failure or resulting from chronic kidney disease. The expression of HO-1 is strongly inducible by a wide range of stimuli in the kidney, consequent to the kidney's filtration role which means HO-1 is exposed to a wide range of endogenous and exogenous molecules, and it has been shown to be protective in a variety of nephropathological animal models. Interestingly, the positive effect of HO-1 occurs in both hemolysis- and rhabdomyolysis-dominated diseases, where the kidney is extensively exposed to heme (a major HO-1 inducer), as well as in non-heme-dependent diseases such as hypertension, diabetic nephropathy or progression to end-stage renal disease. This highlights the complexity of HO-1's functions, which is also illustrated by the fact that, despite the abundance of preclinical data, no drug targeting HO-1 has so far been translated into clinical use. The objective of this review is to assess current knowledge relating HO-1's role in the kidney and its potential interest as a nephroprotection agent. The potential therapeutic openings will be presented, in particular through the identification of clinical trials targeting this enzyme or its products.
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Affiliation(s)
- Anne Grunenwald
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, F-75006 Paris, France; (A.G.); (L.T.R.)
| | - Lubka T. Roumenina
- Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, F-75006 Paris, France; (A.G.); (L.T.R.)
| | - Marie Frimat
- U1167-RID-AGE, Institut Pasteur de Lille, Inserm, Univ. Lille, F-59000 Lille, France
- Nephrology Department, CHU Lille, Univ. Lille, F-59000 Lille, France
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20
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Hu ZG, Zhou Y, Lin CJ, Yuan GD, He SQ. Emerging recognition of the complement system in hepatic ischemia/reperfusion injury, liver regeneration and recovery (Review). Exp Ther Med 2021; 21:223. [PMID: 33603832 PMCID: PMC7851628 DOI: 10.3892/etm.2021.9654] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 11/26/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatic ischemia/reperfusion injury (IRI) is a result of the ischemic cascade and may occur in the settings of liver trauma, resection and transplantation. Components of the complement system have been indicated to be mediators of hepatic IRI and regulators of liver regeneration. As such, their potential to mediate both beneficial and harmful effects render them key targets for therapy. In the present study, the mechanisms of complement mediating hepatic IRI were discussed with a focus on the different functions of complement in hepatic injury and liver recovery, and an explanation for this apparent paradox is provided, i.e. that the complement products C3a and C5a have an important role in liver damage; however, C3a and C5a are also necessary for liver regeneration. Furthermore, situated at the end of the complement activation cascade, the membrane attack complex is crucial in hepatic IRI and inhibiting the complex with a site-targeted murine complement inhibitor, complement receptor 2-CD59, may improve liver regeneration after partial hepatectomy, even when hepatectomy is combined with ischemia and reperfusion.
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Affiliation(s)
- Zhi-Gao Hu
- Division of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Department of General Surgery, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Yi Zhou
- Division of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Cheng-Jie Lin
- Division of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Department of Hepatopancreatobiliary Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Guan-Dou Yuan
- Division of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Song-Qing He
- Division of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
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21
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Goud PT, Bai D, Abu-Soud HM. A Multiple-Hit Hypothesis Involving Reactive Oxygen Species and Myeloperoxidase Explains Clinical Deterioration and Fatality in COVID-19. Int J Biol Sci 2021; 17:62-72. [PMID: 33390833 PMCID: PMC7757048 DOI: 10.7150/ijbs.51811] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 10/07/2020] [Indexed: 02/06/2023] Open
Abstract
Multi-system involvement and rapid clinical deterioration are hallmarks of coronavirus disease 2019 (COVID-19) related mortality. The unique clinical phenomena in severe COVID-19 can be perplexing, and they include disproportionately severe hypoxemia relative to lung alveolar-parenchymal pathology and rapid clinical deterioration, with poor response to O2 supplementation, despite preserved lung mechanics. Factors such as microvascular injury, thromboembolism, pulmonary hypertension, and alteration in hemoglobin structure and function could play important roles. Overwhelming immune response associated with "cytokine storms" could activate reactive oxygen species (ROS), which may result in consumption of nitric oxide (NO), a critical vasodilation regulator. In other inflammatory infections, activated neutrophils are known to release myeloperoxidase (MPO) in a natural immune response, which contributes to production of hypochlorous acid (HOCl). However, during overwhelming inflammation, HOCl competes with O2 at heme binding sites, decreasing O2 saturation. Moreover, HOCl contributes to several oxidative reactions, including hemoglobin-heme iron oxidation, heme destruction, and subsequent release of free iron, which mediates toxic tissue injury through additional generation of ROS and NO consumption. Connecting these reactions in a multi-hit model can explain generalized tissue damage, vasoconstriction, severe hypoxia, and precipitous clinical deterioration in critically ill COVID-19 patients. Understanding these mechanisms is critical to develop therapeutic strategies to combat COVID-19.
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Affiliation(s)
- Pravin T Goud
- Division of Reproductive Endocrinology and Infertility & California IVF Fertility Center, Department of Obstetrics and Gynecology, University of California Davis, Sacramento, CA, 95833, USA
- California Northstate University Medical College, Elk Grove, CA, 95757, USA
| | - David Bai
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Husam M Abu-Soud
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, 48201, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
- Department of Microbiology, Immunology and Biochemistry, Wayne State University School of Medicine, Detroit, MI, 48201, USA
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22
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Huber-Lang MS, Ignatius A, Köhl J, Mannes M, Braun CK. Complement in trauma-Traumatised complement? Br J Pharmacol 2020; 178:2863-2879. [PMID: 32880897 DOI: 10.1111/bph.15245] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/23/2020] [Accepted: 08/17/2020] [Indexed: 12/17/2022] Open
Abstract
Physical trauma represents a major global burden. The trauma-induced response, including activation of the innate immune system, strives for regeneration but can also lead to post-traumatic complications. The complement cascade is rapidly activated by damaged tissue, hypoxia, exogenous proteases and others. Activated complement can sense, mark and clear both damaged tissue and pathogens. However, excessive and insufficient activation of complement can result in a dysfunctional immune and organ response. Similar to acute coagulopathy, complementopathy can develop with enhanced anaphylatoxin generation and an impairment of complement effector functions. Various remote organ effects are induced or modulated by complement activation. Frequently, established trauma treatments are double-edged. On one hand, they help stabilising haemodynamics and oxygen supply as well as injured organs and on the other hand, they also drive complement activation. Immunomodulatory approaches aim to reset trauma-induced disbalance of complement activation and thus may change surgical trauma management procedures to improve outcome. LINKED ARTICLES: This article is part of a themed issue on Canonical and non-canonical functions of the complement system in health and disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.14/issuetoc.
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Affiliation(s)
- Markus S Huber-Lang
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital of Ulm, Ulm, Germany
| | - Anita Ignatius
- Institue of Orthopaedic Research and Biomechanics, University Hospital of Ulm, Ulm, Germany
| | - Jörg Köhl
- Institute for Systemic Inflammatory Research, University of Lübeck, Lübeck, Germany.,Division of Immunobiology, Cincinnati Children's Hospital Medical Centre, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Marco Mannes
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital of Ulm, Ulm, Germany
| | - Christian Karl Braun
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital of Ulm, Ulm, Germany.,Department of Paediatrics and Adolescent Medicine, University Hospital of Ulm, Ulm, Germany
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23
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Abstract
Physical trauma can affect any individual and is globally accountable for more than one in every ten deaths. Although direct severe kidney trauma is relatively infrequent, extrarenal tissue trauma frequently results in the development of acute kidney injury (AKI). Various causes, including haemorrhagic shock, rhabdomyolysis, use of nephrotoxic drugs and infectious complications, can trigger and exacerbate trauma-related AKI (TRAKI), particularly in the presence of pre-existing or trauma-specific risk factors. Injured, hypoxic and ischaemic tissues expose the organism to damage-associated and pathogen-associated molecular patterns, and oxidative stress, all of which initiate a complex immunopathophysiological response that results in macrocirculatory and microcirculatory disturbances in the kidney, and functional impairment. The simultaneous activation of components of innate immunity, including leukocytes, coagulation factors and complement proteins, drives kidney inflammation, glomerular and tubular damage, and breakdown of the blood-urine barrier. This immune response is also an integral part of the intense post-trauma crosstalk between the kidneys, the nervous system and other organs, which aggravates multi-organ dysfunction. Necessary lifesaving procedures used in trauma management might have ambivalent effects as they stabilize injured tissue and organs while simultaneously exacerbating kidney injury. Consequently, only a small number of pathophysiological and immunomodulatory therapeutic targets for TRAKI prevention have been proposed and evaluated.
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24
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Janciauskiene S, Vijayan V, Immenschuh S. TLR4 Signaling by Heme and the Role of Heme-Binding Blood Proteins. Front Immunol 2020; 11:1964. [PMID: 32983129 PMCID: PMC7481328 DOI: 10.3389/fimmu.2020.01964] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/21/2020] [Indexed: 12/12/2022] Open
Abstract
Toll-like receptors (TLRs), also known as pattern recognition receptors, respond to exogenous pathogens and to intrinsic danger signals released from damaged cells and tissues. The tetrapyrrole heme has been suggested to be an agonist for TLR4, the receptor for the pro-inflammatory bacterial component lipopolysaccharide (LPS), synonymous with endotoxin. Heme is a double-edged sword with contradictory functions. On the one hand, it has vital cellular functions as the prosthetic group of hemoproteins including hemoglobin, myoglobin, and cytochromes. On the other hand, if released from destabilized hemoproteins, non-protein bound or “free” heme can have pro-oxidant and pro-inflammatory effects, the mechanisms of which are not fully understood. In this review, the complex interactions between heme and TLR4 are discussed with a particular focus on the role of heme-binding serum proteins in handling extracellular heme and its impact on TLR4 signaling. Moreover, the role of heme as a direct and indirect trigger of TLR4 activation and species-specific differences in the regulation of heme-dependent TLR4 signaling are highlighted.
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Affiliation(s)
- Sabina Janciauskiene
- Department of Pulmonology, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover Medical School, Hanover, Germany
| | - Vijith Vijayan
- Institute for Transfusion Medicine and Transplant Engineering, Hannover Medical School, Hanover, Germany
| | - Stephan Immenschuh
- Institute for Transfusion Medicine and Transplant Engineering, Hannover Medical School, Hanover, Germany
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25
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Corona D, Ekser B, Gioco R, Caruso M, Schipa C, Veroux P, Giaquinta A, Granata A, Veroux M. Heme-Oxygenase and Kidney Transplantation: A Potential for Target Therapy? Biomolecules 2020; 10:E840. [PMID: 32486245 PMCID: PMC7355572 DOI: 10.3390/biom10060840] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/24/2020] [Accepted: 05/27/2020] [Indexed: 12/18/2022] Open
Abstract
Kidney transplantation is a well-established therapy for patients with end-stage renal disease. While a significant improvement of short-term results has been achieved in the short-term, similar results were not reported in the long-term. Heme-oxygenase (HO) is the rate-limiting enzyme in heme catabolism, converting heme to iron, carbon monoxide, and biliverdin. Heme-oxygenase overexpression may be observed in all phases of transplant processes, including brain death, recipient management, and acute and chronic rejection. HO induction has been proved to provide a significant reduction of inflammatory response and a reduction of ischemia and reperfusion injury in organ transplantation, as well as providing a reduction of incidence of acute rejection. In this review, we will summarize data on HO and kidney transplantation, suggesting possible clinical applications in the near future to improve the long-term outcomes.
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Affiliation(s)
- Daniela Corona
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (D.C.); (M.C.)
- Organ Transplant Unit, University Hospital of Catania, 95123 Catania, Italy; (P.V.); (A.G.)
| | - Burcin Ekser
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46077, USA;
| | - Rossella Gioco
- General Surgery Unit, University Hospital of Catania, 95123 Catania, Italy; (R.G.); (C.S.)
| | - Massimo Caruso
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (D.C.); (M.C.)
| | - Chiara Schipa
- General Surgery Unit, University Hospital of Catania, 95123 Catania, Italy; (R.G.); (C.S.)
| | - Pierfrancesco Veroux
- Organ Transplant Unit, University Hospital of Catania, 95123 Catania, Italy; (P.V.); (A.G.)
| | - Alessia Giaquinta
- Organ Transplant Unit, University Hospital of Catania, 95123 Catania, Italy; (P.V.); (A.G.)
| | | | - Massimiliano Veroux
- Organ Transplant Unit, University Hospital of Catania, 95123 Catania, Italy; (P.V.); (A.G.)
- General Surgery Unit, University Hospital of Catania, 95123 Catania, Italy; (R.G.); (C.S.)
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26
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Interplay of Heme with Macrophages in Homeostasis and Inflammation. Int J Mol Sci 2020; 21:ijms21030740. [PMID: 31979309 PMCID: PMC7036926 DOI: 10.3390/ijms21030740] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/17/2020] [Accepted: 01/17/2020] [Indexed: 12/16/2022] Open
Abstract
Macrophages are an integral part of the mononuclear phagocyte system that is critical for maintaining immune homeostasis. They play a key role for initiation and modulation of immunological responses in inflammation and infection. Moreover, macrophages exhibit a wide spectrum of tissue-specific phenotypes in steady-state and pathophysiological conditions. Recent clinical and experimental evidence indicates that the ubiquitous compound heme is a crucial regulator of these cells, e.g., in the differentiation of monocytes to tissue-resident macrophages and/ or in activation by inflammatory stimuli. Notably, heme, an iron containing tetrapyrrole, is essential as a prosthetic group of hemoproteins (e.g., hemoglobin and cytochromes), whereas non-protein bound free or labile heme can be harmful via pro-oxidant, pro-inflammatory, and cytotoxic effects. In this review, it will be discussed how the complex interplay of heme with macrophages regulates homeostasis and inflammation via modulating macrophage inflammatory characteristics and/ or hematopoiesis. A particular focus will be the distinct roles of intra- and extracellular labile heme and the regulation of its availability by heme-binding proteins. Finally, it will be addressed how heme modulates macrophage functions via specific transcriptional factors, in particular the nuclear repressor BTB and CNC homologue (BACH)1 and Spi-C.
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