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Garofalo M, Payros D, Taieb F, Oswald E, Nougayrède JP, Oswald IP. From ribosome to ribotoxins: understanding the toxicity of deoxynivalenol and Shiga toxin, two food borne toxins. Crit Rev Food Sci Nutr 2023:1-13. [PMID: 37862145 DOI: 10.1080/10408398.2023.2271101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2023]
Abstract
Ribosomes that synthesize proteins are among the most central and evolutionarily conserved organelles. Given the key role of proteins in cellular functions, prokaryotic and eukaryotic pathogens have evolved potent toxins to inhibit ribosomal functions and weaken their host. Many of these ribotoxin-producing pathogens are associated with food. For example, food can be contaminated with bacterial pathogens that produce the ribotoxin Shiga toxin, but also with the fungal ribotoxin deoxynivalenol. Shiga toxin cleaves ribosomal RNA, while deoxynivalenol binds to and inhibits the peptidyl transferase center. Despite their distinct modes of action, both groups of ribotoxins hinder protein translation, but also trigger other comparable toxic effects, which depend or not on the activation of the ribotoxic stress response. Ribotoxic stress response-dependent effects include inflammation and apoptosis, whereas ribotoxic stress response-independent effects include endoplasmic reticulum stress, oxidative stress, and autophagy. For other effects, such as cell cycle arrest and cytoskeleton modulation, the involvement of the ribotoxic stress response is still controversial. Ribotoxins affect one organelle yet induce multiple toxic effects with multiple consequences for the cell. The ribosome can therefore be considered as the cellular "Achilles heel" targeted by food borne ribotoxins. Considering the high toxicity of ribotoxins, they pose a substantial health risk, as humans are highly susceptible to widespread exposure to these toxins through contaminated food sources.
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Affiliation(s)
- Marion Garofalo
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRAE, ENVT, INP-Purpan, UPS, Toulouse, France
- IRSD, Université de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
| | - Delphine Payros
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRAE, ENVT, INP-Purpan, UPS, Toulouse, France
- IRSD, Université de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
| | - Frederic Taieb
- IRSD, Université de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
| | - Eric Oswald
- IRSD, Université de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France
- CHU Toulouse, Hôpital Purpan, Toulouse, France
| | | | - Isabelle P Oswald
- Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRAE, ENVT, INP-Purpan, UPS, Toulouse, France
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Dong W, Gong F, Zhao Y, Bai H, Yang R. Ferroptosis and mitochondrial dysfunction in acute central nervous system injury. Front Cell Neurosci 2023; 17:1228968. [PMID: 37622048 PMCID: PMC10445767 DOI: 10.3389/fncel.2023.1228968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/20/2023] [Indexed: 08/26/2023] Open
Abstract
Acute central nervous system injuries (ACNSI), encompassing traumatic brain injury (TBI), non-traumatic brain injury like stroke and encephalomeningitis, as well as spinal cord injuries, are linked to significant rates of disability and mortality globally. Nevertheless, effective and feasible treatment plans are still to be formulated. There are primary and secondary injuries occurred after ACNSI. Most ACNSIs exhibit comparable secondary injuries, which offer numerous potential therapeutic targets for enhancing clinical outcomes. Ferroptosis, a newly discovered form of cell death, is characterized as a lipid peroxidation process that is dependent on iron and oxidative conditions, which is also indispensable to mitochondria. Ferroptosis play a vital role in many neuropathological pathways, and ACNSIs may induce mitochondrial dysfunction, thereby indicating the essentiality of the mitochondrial connection to ferroptosis in ACNSIs. Nevertheless, there remains a lack of clarity regarding the involvement of mitochondria in the occurrence of ferroptosis as a secondary injuries of ACNSIs. In recent studies, anti-ferroptosis agents such as the ferroptosis inhibitor Ferrostain-1 and iron chelation therapy have shown potential in ameliorating the deleterious effects of ferroptosis in cases of traumatic ACNSI. The importance of this evidence is extremely significant in relation to the research and control of ACNSIs. Therefore, our review aims to provide researchers focusing on enhancing the therapeutic outcomes of ACNSIs with valuable insights by summarizing the physiopathological mechanisms of ACNSIs and exploring the correlation between ferroptosis, mitochondrial dysfunction, and ACNSIs.
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Affiliation(s)
- Wenxue Dong
- Department of Neurosurgery, General Hospital of Southern Theatre Command of PLA, Guangzhou, China
| | - Fanghe Gong
- Department of Neurosurgery, General Hospital of Southern Theatre Command of PLA, Guangzhou, China
| | - Yu Zhao
- School of Medicine, Xizang Minzu University, Xianyang, China
| | - Hongmin Bai
- Department of Neurosurgery, General Hospital of Southern Theatre Command of PLA, Guangzhou, China
| | - Ruixin Yang
- Department of Neurosurgery, General Hospital of Southern Theatre Command of PLA, Guangzhou, China
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Dennhardt S, Pirschel W, Wissuwa B, Imhof D, Daniel C, Kielstein JT, Hennig-Pauka I, Amann K, Gunzer F, Coldewey SM. Targeting the innate repair receptor axis via erythropoietin or pyroglutamate helix B surface peptide attenuates hemolytic-uremic syndrome in mice. Front Immunol 2022; 13:1010882. [PMID: 36211426 PMCID: PMC9537456 DOI: 10.3389/fimmu.2022.1010882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 08/30/2022] [Indexed: 11/30/2022] Open
Abstract
Hemolytic-uremic syndrome (HUS) can occur as a systemic complication of infections with Shiga toxin (Stx)-producing Escherichia coli and is characterized by microangiopathic hemolytic anemia and acute kidney injury. Hitherto, therapy has been limited to organ-supportive strategies. Erythropoietin (EPO) stimulates erythropoiesis and is approved for the treatment of certain forms of anemia, but not for HUS-associated hemolytic anemia. EPO and its non-hematopoietic analog pyroglutamate helix B surface peptide (pHBSP) have been shown to mediate tissue protection via an innate repair receptor (IRR) that is pharmacologically distinct from the erythropoiesis-mediating receptor (EPO-R). Here, we investigated the changes in endogenous EPO levels in patients with HUS and in piglets and mice subjected to preclinical HUS models. We found that endogenous EPO was elevated in plasma of humans, piglets, and mice with HUS, regardless of species and degree of anemia, suggesting that EPO signaling plays a role in HUS pathology. Therefore, we aimed to examine the therapeutic potential of EPO and pHBSP in mice with Stx-induced HUS. Administration of EPO or pHBSP improved 7-day survival and attenuated renal oxidative stress but did not significantly reduce renal dysfunction and injury in the employed model. pHBSP, but not EPO, attenuated renal nitrosative stress and reduced tubular dedifferentiation. In conclusion, targeting the EPO-R/IRR axis reduced mortality and renal oxidative stress in murine HUS without occurrence of thromboembolic complications or other adverse side effects. We therefore suggest that repurposing EPO for the treatment of patients with hemolytic anemia in HUS should be systematically investigated in future clinical trials.
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Affiliation(s)
- Sophie Dennhardt
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
- Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Wiebke Pirschel
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Bianka Wissuwa
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Diana Imhof
- Pharmaceutical Biochemistry and Bioanalytics, Pharmaceutical Institute, University of Bonn, Bonn, Germany
| | - Christoph Daniel
- Department of Nephropathology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Jan T. Kielstein
- Medical Clinic V, Nephrology | Rheumatology | Blood Purification, Academic Teaching Hospital Braunschweig, Braunschweig, Germany
| | - Isabel Hennig-Pauka
- Field Station for Epidemiology, University of Veterinary Medicine Hannover, Bakum, Germany
| | - Kerstin Amann
- Department of Nephropathology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Florian Gunzer
- Department of Hospital Infection Control, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Sina M. Coldewey
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Jena, Germany
- Septomics Research Center, Jena University Hospital, Jena, Germany
- Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
- *Correspondence: Sina M. Coldewey,
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Landoni VI, Pittaluga JR, Carestia A, Castillo LA, Nebel MDC, Martire-Greco D, Birnberg-Weiss F, Schattner M, Schierloh P, Fernández GC. Neutrophil Extracellular Traps Induced by Shiga Toxin and Lipopolysaccharide-Treated Platelets Exacerbate Endothelial Cell Damage. Front Cell Infect Microbiol 2022; 12:897019. [PMID: 35811684 PMCID: PMC9262415 DOI: 10.3389/fcimb.2022.897019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in the pediatric population. The etiology of HUS is linked to Gram-negative, Shiga toxin (Stx)-producing enterohemorrhagic bacterial infections. While the effect of Stx is focused on endothelial damage of renal glomerulus, cytokines induced by Stx or bacterial lipopolysaccharide (LPS) and polymorphonuclear cells (PMNs) are involved in the development of the disease. PMN release neutrophil extracellular traps (NETs) to eliminate pathogens, although NETs favor platelets (Plts) adhesion/thrombus formation and can cause tissue damage within blood vessels. Since thrombus formation and occlusion of vessels are characteristic of HUS, PMN–Plts interaction in the context of Stx may promote netosis and contribute to the endothelial damage observed in HUS. The aim of this study was to determine the relevance of netosis induced by Stx in the context of LPS-sensitized Plts on endothelial damage. We observed that Stx2 induced a marked enhancement of netosis promoted by Plts after LPS stimulation. Several factors seemed to promote this phenomenon. Stx2 itself increased the expression of its receptor on Plts, increasing toxin binding. Stx2 also increased LPS binding to Plts. Moreover, Stx2 amplified LPS induced P-selectin expression on Plts and mixed PMN–Plts aggregates formation, which led to activation of PMN enhancing dramatically NETs formation. Finally, experiments revealed that endothelial cell damage mediated by PMN in the context of Plts treated with LPS and Stx2 was decreased when NETs were disrupted or when mixed aggregate formation was impeded using an anti-P-selectin antibody. Using a murine model of HUS, systemic endothelial damage/dysfunction was decreased when NETs were disrupted, or when Plts were depleted, indicating that the promotion of netosis by Plts in the context of LPS and Stx2 plays a fundamental role in endothelial toxicity. These results provide insights for the first time into the pivotal role of Plts as enhancers of endothelial damage through NETs promotion in the context of Stx and LPS. Consequently, therapies designed to reduce either the formation of PMN–Plts aggregates or NETs formation could lessen the consequences of endothelial damage in HUS.
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Affiliation(s)
- Verónica Inés Landoni
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Jose R. Pittaluga
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Agostina Carestia
- Laboratorio de Trombosis Experimental e Inmunobiología de la Inflamación, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Luis Alejandro Castillo
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Marcelo de Campos Nebel
- Laboratorio de Mutagénesis, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Daiana Martire-Greco
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Federico Birnberg-Weiss
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Mirta Schattner
- Laboratorio de Trombosis Experimental e Inmunobiología de la Inflamación, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Pablo Schierloh
- Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática, Centro Científico Tecnológico Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina
| | - Gabriela C. Fernández
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
- *Correspondence: Gabriela C. Fernández, ;
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Kume Y, Go H, Maeda R, Suyama K, Mori T, Kawasaki Y, Hashimoto K, Hosoya M. Gene expression profile and injury sites in mice treated with Shiga toxin 2 and lipopolysaccharide as a Shiga toxin-associated hemolytic uremic syndrome model. Physiol Genomics 2022; 54:153-165. [PMID: 35384732 DOI: 10.1152/physiolgenomics.00124.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Shiga toxin 2 (Stx2) and lipopolysaccharide (LPS) contribute to the development of hemolytic uremic syndrome (HUS). Mouse models of HUS induced by LPS/Stx2 have been used for elucidating HUS pathophysiology and for therapeutic development. However, the underlying molecular mechanisms and detailed injury sites in this model remain unknown. We analyzed mouse kidneys after LPS/Stx2 administration using microarrays. Decreased urinary osmolality and urinary potassium were observed after LPS/Stx2 administration, suggestive of distal nephron disorders. A total of 1212 and 1016 differentially expressed genes were identified in microarrays at 6 and 72 h after LPS/Stx2 administration, respectively, compared with those in controls. Ingenuity pathway analysis revealed activation of TNFR1/2, iNOS, and IL-6 signaling at both time points, and inhibition of pathways associated with lipid metabolism at 72 h only. The strongly downregulated genes in the 72-h group were expressed in the distal nephrons. In particular, genes associated with distal convoluted tubule (DCT) 2 /connecting tubule (CNT) and principal cells of the cortical collection duct (CCD) were downregulated to a greater extent than those associated with DCT1 and intercalated cells. Stx receptor globotriaosylceramide 3 (Gb3) revealed no colocalization with DCT1-specific Pvalb and intercalated cell-specific Slc26a4 but did present colocalization with Slc12a3 (present in both DCT1 and DCT2), and Aqp2 in principal cells. Gb3 localization tended to coincide with the segment in which the downregulated genes were present. Thus, the LPS/Stx2-induced kidney injury model represents damage to DCT2/CNT and principal cells in the CCD, based on molecular, biological, and physiological findings.
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Affiliation(s)
- Yohei Kume
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
| | - Hayato Go
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
| | - Ryo Maeda
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
| | - Kazuhide Suyama
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
| | - Tsutomu Mori
- Department of Human Life Sciences, School of Nursing, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Yukihiko Kawasaki
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
| | - Koichi Hashimoto
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
| | - Mitsuaki Hosoya
- Department of Pediatrics, Fukushima Medical University, Fukushima, Japan
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Schoettler M, Chonat S, Williams K, Lehmann L. Emerging therapeutic and preventive approaches to transplant-associated thrombotic microangiopathy. Curr Opin Hematol 2021; 28:408-416. [PMID: 34534983 PMCID: PMC9908033 DOI: 10.1097/moh.0000000000000687] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
PURPOSE OF REVIEW Transplant-associated thrombotic microangiopathy (TA-TMA) is a complication that can occur in both allogeneic and autologous haematopoietic cellular therapy (HCT) recipients and is associated with significant morbidity and mortality. Although TA-TMA is a complex disease, there is emerging evidence that complement activation and endothelial dysfunction play a key role in the pathophysiology of the disease. The use of eculizumab has improved survival in patients with high risk and severe disease, but mortality rates in treated patients still exceed 30%, highlighting the need for novel approaches. RECENT FINDINGS There are multiple ongoing and planned clinical trials investigating novel complement agents in TA-TMA and other TMAs. Drugs vary by targets of the complement system, mechanism, and form of administration. Clinical trial designs include single arm studies that span across multiple age groups including children, and double-blind, randomized, placebo-controlled studies. These studies will provide robust data to inform the care of patients with TA-TMA in the future. In addition to multiple promising therapeutic agents, preventing TA-TMA is an emerging strategy. Agents known to protect the endothelium from damage and augment endothelial function by promoting anti-inflammatory and antithrombotic effects may have a role in preventing TA-TMA or ameliorating the severity, though additional studies are needed. SUMMARY Novel therapeutic agents for TA-TMA inhibition of the complement system are under investigation and prophylactic strategies of endothelial protection are emerging. Further understanding of the pathophysiology of the disease may identify additional therapeutic targets. Multiinstitutional, collaborative clinical trials are needed to determine the safety and efficacy of these agents going forward.
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Affiliation(s)
- Michelle Schoettler
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta and Department of Pediatrics, Emory University, Pediatric Hematopoietic Cellular Therapy, Atlanta, GA
| | - Satheesh Chonat
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta and Department of Pediatrics, Pediatric Hematology, Emory University, Atlanta, GA
| | - Kirsten Williams
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta and Department of Pediatrics, Emory University, Pediatric Hematopoietic Cellular Therapy, Atlanta, GA
| | - Leslie Lehmann
- Boston Children’s/Dana Farber Cancer and Blood Disorders Center, Pediatric Hematopoietic Cellular Therapies
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Rejection-associated Phenotype of De Novo Thrombotic Microangiopathy Represents a Risk for Premature Graft Loss. Transplant Direct 2021; 7:e779. [PMID: 34712779 PMCID: PMC8547913 DOI: 10.1097/txd.0000000000001239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/19/2021] [Accepted: 09/08/2021] [Indexed: 11/26/2022] Open
Abstract
Supplemental Digital Content is available in the text. Background. Thrombotic microangiopathy (TMA) significantly affects kidney graft survival, but its pathophysiology remains poorly understood. Methods. In this multicenter, retrospective, case–control paired study designed to control for donor-associated risks, we assessed the recipients’ risk factors for de novo TMA development and its effects on graft survival. The study group consists of patients with TMA found in case biopsies from 2000 to 2019 (n = 93), and the control group consists of recipients of paired kidney grafts (n = 93). Graft follow-up was initiated at the time of TMA diagnosis and at the same time in the corresponding paired kidney graft. Results. The TMA group displayed higher peak panel-reactive antibodies, more frequent retransplantation status, and longer cold ischemia time in univariable analysis. In the multivariable regression model, longer cold ischemia times (odds ratio, 1.18; 95% confidence interval [CI], 1.01-1.39; P = 0.043) and higher peak pretransplant panel-reactive antibodies (odds ratio, 1.03; 95% CI, 1.01-1.06; P = 0.005) were found to be associated with increased risk of de novo TMA. The risk of graft failure was higher in the TMA group at 5 y (hazard ratio [HR], 3.99; 95% CI, 2.04-7.84; P < 0.0001). Concomitant rejection significantly affected graft prognosis at 5 y (HR, 6.36; 95% CI, 2.92-13.87; P < 0.001). De novo TMA associated with the active antibody-mediated rejection was associated with higher risk of graft failure at 5 y (HR, 3.43; 95% CI, 1.69-6.98; P < 0.001) compared with other TMA. Conclusions. Longer cold ischemia and allosensitization play a role in de novo TMA development, whereas TMA as a part of active antibody-mediated rejection was associated with the highest risk for premature graft loss.
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Dumas A, Knaus UG. Raising the 'Good' Oxidants for Immune Protection. Front Immunol 2021; 12:698042. [PMID: 34149739 PMCID: PMC8213335 DOI: 10.3389/fimmu.2021.698042] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/18/2021] [Indexed: 12/12/2022] Open
Abstract
Redox medicine is a new therapeutic concept targeting reactive oxygen species (ROS) and secondary reaction products for health benefit. The concomitant function of ROS as intracellular second messengers and extracellular mediators governing physiological redox signaling, and as damaging radicals instigating or perpetuating various pathophysiological conditions will require selective strategies for therapeutic intervention. In addition, the reactivity and quantity of the oxidant species generated, its source and cellular location in a defined disease context need to be considered to achieve the desired outcome. In inflammatory diseases associated with oxidative damage and tissue injury, ROS source specific inhibitors may provide more benefit than generalized removal of ROS. Contemporary approaches in immunity will also include the preservation or even elevation of certain oxygen metabolites to restore or improve ROS driven physiological functions including more effective redox signaling and cell-microenvironment communication, and to induce mucosal barrier integrity, eubiosis and repair processes. Increasing oxidants by host-directed immunomodulation or by exogenous supplementation seems especially promising for improving host defense. Here, we summarize examples of beneficial ROS in immune homeostasis, infection, and acute inflammatory disease, and address emerging therapeutic strategies for ROS augmentation to induce and strengthen protective host immunity.
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Affiliation(s)
- Alexia Dumas
- Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
| | - Ulla G Knaus
- Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
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Transplant-associated thrombotic microangiopathy in pediatric patients: pre-HSCT risk stratification and prophylaxis. Blood Adv 2021; 5:2106-2114. [PMID: 33877298 DOI: 10.1182/bloodadvances.2020003988] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/08/2021] [Indexed: 12/19/2022] Open
Abstract
Transplant-associated thrombotic microangiopathy (TA-TMA) is an endothelial injury syndrome that complicates hematopoietic stem cell transplant (HSCT). Morbidity and mortality from TA-TMA remain high, making prevention critical. We describe our retrospective single-center experience of TA-TMA after pediatric allogeneic HSCT and present a novel pre-HSCT risk-stratification system and prophylaxis regimen. From January 2012 through October 2019, 257 patients underwent 292 allogeneic HSCTs. Prospective risk stratification was introduced in December 2016. High-risk (HR) patients were treated with combination prophylaxis with eicosapentaenoic acid and N-acetylcysteine. The 1-year cumulative incidence of TA-TMA was 6.3% (95% confidence interval [CI], 3.2-9.4). Age ≥10 years, myeloablative conditioning with total body irradiation, HLA mismatch, diagnosis of severe aplastic anemia or malignancy, prior calcineurin inhibitor exposure, and recipient cytomegalovirus seropositivity were found to be pre-HSCT risk factors for development of TA-TMA. Before routine prophylaxis, TA-TMA rates were significantly different between the HR and standard-risk groups, at 28.2% (95% CI, 0-12.7) vs 3.2% (0.1-6.3), respectively (P < .001). After introduction of prophylaxis, the 1-year cumulative incidence of TA-TMA in the HR group decreased to 4.5% (95% CI, 0-13.1; P = .062, compared with the incidence before prophylaxis). Multicenter pediatric studies are needed to validate these risk criteria and to confirm the efficacy of the prophylactic regimen.
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Wijnsma KL, Veissi ST, de Wijs S, van der Velden T, Volokhina EB, Wagener FADTG, van de Kar NCAJ, van den Heuvel LP. Heme as Possible Contributing Factor in the Evolvement of Shiga-Toxin Escherichia coli Induced Hemolytic-Uremic Syndrome. Front Immunol 2020; 11:547406. [PMID: 33414780 PMCID: PMC7783363 DOI: 10.3389/fimmu.2020.547406] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 11/16/2020] [Indexed: 01/29/2023] Open
Abstract
Shiga-toxin (Stx)-producing Escherichia coli hemolytic-uremic syndrome (STEC-HUS) is one of the most common causes of acute kidney injury in children. Stx-mediated endothelial injury initiates the cascade leading to thrombotic microangiopathy (TMA), still the exact pathogenesis remains elusive. Interestingly, there is wide variability in clinical presentation and outcome. One explanation for this could be the enhancement of TMA through other factors. We hypothesize that heme, as released during extensive hemolysis, contributes to the etiology of TMA. Plasma levels of heme and its scavenger hemopexin and degrading enzyme heme-oxygenase-1 (HO-1) were measured in 48 STEC-HUS patients. Subsequently, the effect of these disease-specific heme concentrations, in combination with Stx, was assessed on primary human glomerular microvascular endothelial cells (HGMVECs). Significantly elevated plasma heme levels up to 21.2 µM were found in STEC-HUS patients compared to controls and were inversely correlated with low or depleted plasma hemopexin levels (R2 −0.74). Plasma levels of HO-1 are significantly elevated compared to controls. Interestingly, especially patients with high heme levels (n = 12, heme levels above 75 quartile range) had high plasma HO-1 levels with median of 332.5 (86–720) ng/ml (p = 0.008). Furthermore, heme is internalized leading to a significant increase in reactive oxygen species production and stimulated both nuclear translocation of NF-κB and increased levels of its target gene (tissue factor). In conclusion, we are the first to show elevated heme levels in patients with STEC-HUS. These increased heme levels mediate endothelial injury by promoting oxidative stress and a pro-inflammatory and pro-thrombotic state. Hence, heme may be a contributing and driving factor in the pathogenesis of STEC-HUS and could potentially amplify the cascade leading to TMA.
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Affiliation(s)
- Kioa L Wijnsma
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Susan T Veissi
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Sem de Wijs
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Thea van der Velden
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Elena B Volokhina
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Frank A D T G Wagener
- Department of Dentistry-Orthodontics and Craniofacial Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Nicole C A J van de Kar
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - L P van den Heuvel
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands.,Department of Development and Regeneration, University Hospital Leuven, Leuven, Belgium
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11
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Abstract
The kidney harbours different types of endothelia, each with specific structural and functional characteristics. The glomerular endothelium, which is highly fenestrated and covered by a rich glycocalyx, participates in the sieving properties of the glomerular filtration barrier and in the maintenance of podocyte structure. The microvascular endothelium in peritubular capillaries, which is also fenestrated, transports reabsorbed components and participates in epithelial cell function. The endothelium of large and small vessels supports the renal vasculature. These renal endothelia are protected by regulators of thrombosis, inflammation and complement, but endothelial injury (for example, induced by toxins, antibodies, immune cells or inflammatory cytokines) or defects in factors that provide endothelial protection (for example, regulators of complement or angiogenesis) can lead to acute or chronic renal injury. Moreover, renal endothelial cells can transition towards a mesenchymal phenotype, favouring renal fibrosis and the development of chronic kidney disease. Thus, the renal endothelium is both a target and a driver of kidney and systemic cardiovascular complications. Emerging therapeutic strategies that target the renal endothelium may lead to improved outcomes for both rare and common renal diseases.
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12
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Patry C, Plotnicki K, Betzen C, Ortiz AP, Pappan KL, Satchell SC, Mathieson PW, Bielaszewska M, Karch H, Tönshoff B, Rafat N. Metabolomic analysis of Shiga toxin 2a-induced injury in conditionally immortalized glomerular endothelial cells. Metabolomics 2019; 15:131. [PMID: 31576432 DOI: 10.1007/s11306-019-1594-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 09/25/2019] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Shiga toxin 2a (Stx2a) induces hemolytic uremic syndrome (STEC HUS) by targeting glomerular endothelial cells (GEC). OBJECTIVES We investigated in a metabolomic analysis the response of a conditionally immortalized, stable glomerular endothelial cell line (ciGEnC) to Stx2a stimulation as a cell culture model for STEC HUS. METHODS CiGEnC were treated with tumor necrosis factor-(TNF)α, Stx2a or sequentially with TNFα and Stx2a. We performed a metabolomic high-throughput screening by lipid- or gas chromatography and subsequent mass spectrometry. Metabolite fold changes in stimulated ciGEnC compared to untreated cells were calculated. RESULTS 320 metabolites were identified and investigated. In response to TNFα + Stx2a, there was a predominant increase in intracellular free fatty acids and amino acids. Furthermore, lipid- and protein derived pro-inflammatory mediators, oxidative stress and an augmented intracellular energy turnover were increased in ciGEnC. Levels of most biochemicals related to carbohydrate metabolism remained unchanged. CONCLUSION Stimulation of ciGEnC with TNFα + Stx2a is associated with profound metabolic changes indicative of increased inflammation, oxidative stress and energy turnover.
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Affiliation(s)
- Christian Patry
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120, Heidelberg, Germany
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, 69120, Heidelberg, Germany
| | - Kathrin Plotnicki
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120, Heidelberg, Germany
| | - Christian Betzen
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120, Heidelberg, Germany
- Division of Functional Genome Analysis, German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany
| | - Alba Perez Ortiz
- Department of Neonatology, University Children's Hospital Mannheim, University of Heidelberg, 68167, Mannheim, Germany
| | - Kirk L Pappan
- Metabolon, Inc., 617 Davis Drive, Suite 400, Durham, NC, 27713, USA
| | - Simon C Satchell
- Learning and Research Southmead Hospital Bristol, University of Bristol, Bristol, BS8 1TH, UK
| | - Peter W Mathieson
- The Principal's Office, University of Edinburgh, Edinburgh, EH8 9YL, UK
| | - Martina Bielaszewska
- Institute for Hygiene, University of Münster, 48149, Münster, Germany
- Reference Laboratory for E. coli and Shigella, National Public Health Institute, Srobarova 48, 10042, Prague, Czech Republic
| | - Helge Karch
- Institute for Hygiene, University of Münster, 48149, Münster, Germany
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120, Heidelberg, Germany
| | - Neysan Rafat
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120, Heidelberg, Germany.
- Department of Neonatology, University Children's Hospital Mannheim, University of Heidelberg, 68167, Mannheim, Germany.
- Department of Pharmaceutical Sciences, Bahá'í Institute of Higher Education (BIHE), Teheran, Iran.
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13
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Berdasco C, Pinto A, Calabró V, Arenas D, Cangelosi A, Geoghegan P, Evelson P, Goldstein J. Shiga toxin 2 from enterohemorrhagic Escherichia coli induces reactive glial cells and neurovascular disarrangements including edema and lipid peroxidation in the murine brain hippocampus. J Biomed Sci 2019; 26:16. [PMID: 30732602 PMCID: PMC6366040 DOI: 10.1186/s12929-019-0509-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/01/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Shiga toxin 2 from enterohemorrhagic Escherichia coli is the etiologic agent of bloody diarrhea, hemolytic uremic syndrome and derived encephalopathies that may result to death in patients. Being a Gram negative bacterium, lipopolysaccharide is also released. Particularly, the hippocampus has been found affected in patients intoxicated with Shiga toxin 2. In the current work, the deleterious effects of Shiga toxin 2 and lipopolysaccharide are investigated in detail in hippocampal cells for the first time in a translational murine model, providing conclusive evidences on how these toxins may damage in the observed clinic cases. METHODS Male NIH mice (25 g) were injected intravenously with saline solution, lipopolysaccharide, Shiga toxin 2 or a combination of Shiga toxin 2 with lipopolysaccharide. Brain water content assay was made to determine brain edema. Another set of animals were intracardially perfused with a fixative solution and their brains were subjected to immunofluorescence with lectins to determine the microvasculature profile, and anti-GFAP, anti-NeuN, anti-MBP and anti-Iba1 to study reactive astrocytes, neuronal damage, myelin dysarrangements and microglial state respectively. Finally, the Thiobarbituric Acid Reactive Substances Assay was made to determine lipid peroxidation. In all assays, statistical significance was performed using the One-way analysis of variance followed by Bonferroni post hoc test. RESULTS Systemic sublethal administration of Shiga toxin 2 increased the expressions of astrocytic GFAP and microglial Iba1, and decreased the expressions of endothelial glycocalyx, NeuN neurons from CA1 pyramidal layer and oligodendrocytic MBP myelin sheath from the fimbria of the hippocampus. In addition, increased interstitial fluids and Thiobarbituric Acid Reactive Substances-derived lipid peroxidation were also found. The observed outcomes were enhanced when sublethal administration of Shiga toxin 2 was co-administered together with lipopolysaccharide. CONCLUSION Systemic sublethal administration of Shiga toxin 2 produced a deterioration of the cells that integrate the vascular unit displaying astrocytic and microglial reactive profiles, while edema and lipid peroxidation were also observed. The contribution of lipopolysaccharide to pathogenicity caused by Shiga toxin 2 resulted to enhance the observed hippocampal damage.
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Affiliation(s)
- Clara Berdasco
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Fisiología y Biofísica ‘‘Houssay” (IFIBIO), Laboratorio de Neurofisiopatología, Facultad de Medicina, Paraguay 2155 piso 7, 1121 Buenos Aires, Argentina
| | - Alipio Pinto
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Fisiología y Biofísica ‘‘Houssay” (IFIBIO), Laboratorio de Neurofisiopatología, Facultad de Medicina, Paraguay 2155 piso 7, 1121 Buenos Aires, Argentina
| | - Valeria Calabró
- Universidad de Buenos Aires, CONICET, Instituto de Bioquímica y Medicina Molecular (IBIMOL), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - David Arenas
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Fisiología y Biofísica ‘‘Houssay” (IFIBIO), Laboratorio de Neurofisiopatología, Facultad de Medicina, Paraguay 2155 piso 7, 1121 Buenos Aires, Argentina
| | - Adriana Cangelosi
- Centro Nacional de Control de Calidad de Biológicos (CNCCB), ANLIS “Dr. Carlos G. Malbrán”, Ciudad Autónoma de Buenos Aires, Argentina
| | - Patricia Geoghegan
- Centro Nacional de Control de Calidad de Biológicos (CNCCB), ANLIS “Dr. Carlos G. Malbrán”, Ciudad Autónoma de Buenos Aires, Argentina
| | - Pablo Evelson
- Universidad de Buenos Aires, CONICET, Instituto de Bioquímica y Medicina Molecular (IBIMOL), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Analítica y Fisicoquímica, Cátedra de Química General e Inorgánica, Buenos Aires, Argentina
| | - Jorge Goldstein
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Fisiología y Biofísica ‘‘Houssay” (IFIBIO), Laboratorio de Neurofisiopatología, Facultad de Medicina, Paraguay 2155 piso 7, 1121 Buenos Aires, Argentina
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14
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Jourde-Chiche N, Fakhouri F, Dou L, Bellien J, Burtey S, Frimat M, Jarrot PA, Kaplanski G, Le Quintrec M, Pernin V, Rigothier C, Sallée M, Fremeaux-Bacchi V, Guerrot D, Roumenina LT. Endothelium structure and function in kidney health and disease. Nat Rev Nephrol 2019. [PMID: 30607032 DOI: 10.1038/s4158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
The kidney harbours different types of endothelia, each with specific structural and functional characteristics. The glomerular endothelium, which is highly fenestrated and covered by a rich glycocalyx, participates in the sieving properties of the glomerular filtration barrier and in the maintenance of podocyte structure. The microvascular endothelium in peritubular capillaries, which is also fenestrated, transports reabsorbed components and participates in epithelial cell function. The endothelium of large and small vessels supports the renal vasculature. These renal endothelia are protected by regulators of thrombosis, inflammation and complement, but endothelial injury (for example, induced by toxins, antibodies, immune cells or inflammatory cytokines) or defects in factors that provide endothelial protection (for example, regulators of complement or angiogenesis) can lead to acute or chronic renal injury. Moreover, renal endothelial cells can transition towards a mesenchymal phenotype, favouring renal fibrosis and the development of chronic kidney disease. Thus, the renal endothelium is both a target and a driver of kidney and systemic cardiovascular complications. Emerging therapeutic strategies that target the renal endothelium may lead to improved outcomes for both rare and common renal diseases.
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Affiliation(s)
- Noemie Jourde-Chiche
- Aix-Marseille University, Centre de Nephrologie et Transplantation Renale, AP-HM Hopital de la Conception, Marseille, France.
- Aix-Marseille University, C2VN, INSERM 1263, Institut National de la Recherche Agronomique (INRA) 1260, Faculte de Pharmacie, Marseille, France.
| | - Fadi Fakhouri
- Centre de Recherche en Transplantation et Immunologie, INSERM, Université de Nantes and Department of Nephrology, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Laetitia Dou
- Aix-Marseille University, C2VN, INSERM 1263, Institut National de la Recherche Agronomique (INRA) 1260, Faculte de Pharmacie, Marseille, France
| | - Jeremy Bellien
- Department of Pharmacology, Rouen University Hospital and INSERM, Normandy University, Université de Rouen Normandie, Rouen, France
| | - Stéphane Burtey
- Aix-Marseille University, Centre de Nephrologie et Transplantation Renale, AP-HM Hopital de la Conception, Marseille, France
- Aix-Marseille University, C2VN, INSERM 1263, Institut National de la Recherche Agronomique (INRA) 1260, Faculte de Pharmacie, Marseille, France
| | - Marie Frimat
- Université de Lille, INSERM, Centre Hospitalier Universitaire de Lille, U995, Lille Inflammation Research International Center (LIRIC), Lille, France
- Nephrology Department, Centre Hospitalier Universitaire de Lille, Lille, France
| | - Pierre-André Jarrot
- Aix-Marseille University, C2VN, INSERM 1263, Institut National de la Recherche Agronomique (INRA) 1260, Faculte de Pharmacie, Marseille, France
- Assistance Publique-Hôpitaux de Marseille, Service de Médecine Interne et d'Immunologie Clinique, Hôpital de La Conception, Marseille, France
| | - Gilles Kaplanski
- Aix-Marseille University, C2VN, INSERM 1263, Institut National de la Recherche Agronomique (INRA) 1260, Faculte de Pharmacie, Marseille, France
- Assistance Publique-Hôpitaux de Marseille, Service de Médecine Interne et d'Immunologie Clinique, Hôpital de La Conception, Marseille, France
| | - Moglie Le Quintrec
- Centre Hospitalier Universitaire de Lapeyronie, Département de Néphrologie Dialyse et Transplantation Rénale, Montpellier, France
- Institute for Regenerative Medicine and Biotherapy (IRMB), Montpellier, France
| | - Vincent Pernin
- Centre Hospitalier Universitaire de Lapeyronie, Département de Néphrologie Dialyse et Transplantation Rénale, Montpellier, France
- Institute for Regenerative Medicine and Biotherapy (IRMB), Montpellier, France
| | - Claire Rigothier
- Tissue Bioengineering, Université de Bordeaux, Bordeaux, France
- Service de Néphrologie Transplantation, Dialyse et Aphérèse, Centre Hospitalier Universitaire de Bordeaux, Bordeaux, France
| | - Marion Sallée
- Aix-Marseille University, Centre de Nephrologie et Transplantation Renale, AP-HM Hopital de la Conception, Marseille, France
- Aix-Marseille University, C2VN, INSERM 1263, Institut National de la Recherche Agronomique (INRA) 1260, Faculte de Pharmacie, Marseille, France
| | - Veronique Fremeaux-Bacchi
- Assistance Publique-Hôpitaux de Paris, Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Paris, France
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
| | - Dominique Guerrot
- Normandie Université, Université de Rouen Normandie, Rouen University Hospital, Department of Nephrology, Rouen, France
| | - Lubka T Roumenina
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France.
- Sorbonne Universités, Paris, France.
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
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15
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Dvorak CC, Higham C, Shimano KA. Transplant-Associated Thrombotic Microangiopathy in Pediatric Hematopoietic Cell Transplant Recipients: A Practical Approach to Diagnosis and Management. Front Pediatr 2019; 7:133. [PMID: 31024873 PMCID: PMC6465621 DOI: 10.3389/fped.2019.00133] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 03/21/2019] [Indexed: 01/04/2023] Open
Abstract
Transplant-associated thrombotic microangiopathy (TA-TMA) is an endothelial damage syndrome that is increasingly identified as a complication of both autologous and allogeneic hematopoietic cell transplantation (HCT) in children. If not promptly diagnosed and treated, TA-TMA can lead to significant morbidity (e.g., permanent renal injury) or mortality. However, as the recognition of the early stages of TA-TMA may be difficult, we propose a TA-TMA "triad" of hypertension, thrombocytopenia (or platelet transfusion refractoriness), and elevated lactate dehydrogenase (LDH). While not diagnostic, this triad should prompt further evaluation for TA-TMA. There is increased understanding of the risk factors for the development of TA-TMA, including those which are inherent (e.g., race, genetics), transplant approach-related (e.g., second HCT, use of HLA-mismatched donors), and related to post-transplant events (e.g., receipt of calcineurin inhibitors, development of graft-vs. -host-disease, or certain infections). This understanding should lead to enhanced screening for TA-TMA signs and symptoms in high-risk patients. The pathophysiology of TA-TMA is complex, resulting from a cycle of activation of endothelial cells to produce a pro-coagulant state, along with activation of antigen-presenting cells and lymphocytes, as well as activation of the complement cascade and microthrombi formation. This has led to the formulation of a "Three-Hit Hypothesis" in which patients with either an underlying predisposition to complement activation or pre-existing endothelial injury (Hit 1) undergo a toxic conditioning regimen causing endothelial injury (Hit 2), and then additional insults are triggered by medications, alloreactivity, infections, and/or antibodies (Hit 3). Understanding this cycle of injury permits the development of a specific TA-TMA treatment algorithm designed to treat both the triggers and the drivers of the endothelial injury. Finally, several intriguing approaches to TA-TMA prophylaxis have been identified. Future work on the development of a single diagnostic test with high specificity and sensitivity, and the development of a robust risk-scoring system, will further improve the management of this serious post-transplant complication.
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Affiliation(s)
- Christopher C Dvorak
- Division of Pediatric Allergy, Immunology, and Bone Marrow Transplant, Benioff Children's Hospital, University of California, San Francisco, San Francisco, CA, United States
| | - Christine Higham
- Division of Pediatric Allergy, Immunology, and Bone Marrow Transplant, Benioff Children's Hospital, University of California, San Francisco, San Francisco, CA, United States
| | - Kristin A Shimano
- Division of Pediatric Allergy, Immunology, and Bone Marrow Transplant, Benioff Children's Hospital, University of California, San Francisco, San Francisco, CA, United States
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16
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Exeni RA, Fernandez-Brando RJ, Santiago AP, Fiorentino GA, Exeni AM, Ramos MV, Palermo MS. Pathogenic role of inflammatory response during Shiga toxin-associated hemolytic uremic syndrome (HUS). Pediatr Nephrol 2018; 33:2057-2071. [PMID: 29372302 DOI: 10.1007/s00467-017-3876-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 11/01/2017] [Accepted: 12/07/2017] [Indexed: 01/22/2023]
Abstract
Hemolytic uremic syndrome (HUS) is defined as a triad of noninmune microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. The most frequent presentation is secondary to Shiga toxin (Stx)-producing Escherichia coli (STEC) infections, which is termed postdiarrheal, epidemiologic or Stx-HUS, considering that Stx is the necessary etiological factor. After ingestion, STEC colonize the intestine and produce Stx, which translocates across the intestinal epithelium. Once Stx enters the bloodstream, it interacts with renal endothelial and epithelial cells, and leukocytes. This review summarizes the current evidence about the involvement of inflammatory components as central pathogenic factors that could determine outcome of STEC infections. Intestinal inflammation may favor epithelial leakage and subsequent passage of Stx to the systemic circulation. Vascular damage triggered by Stx promotes not only release of thrombin and increased fibrin concentration but also production of cytokines and chemokines by endothelial cells. Recent evidence from animal models and patients strongly indicate that several immune cells types may participate in HUS physiopathology: neutrophils, through release of proteases and reactive oxygen species (ROS); monocytes/macrophages through secretion of cytokines and chemokines. In addition, high levels of Bb factor and soluble C5b-9 (sC5b-9) in plasma as well as complement factors adhered to platelet-leukocyte complexes, microparticles and microvesicles, suggest activation of the alternative pathway of complement. Thus, acute immune response secondary to STEC infection, the Stx stimulatory effect on different immune cells, and inflammatory stimulus secondary to endothelial damage all together converge to define a strong inflammatory status that worsens Stx toxicity and disease.
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Affiliation(s)
- Ramon Alfonso Exeni
- Departamento de Nefrología, Hospital Municipal del Niño, San Justo, Provincia de Buenos Aires, Argentina
| | - Romina Jimena Fernandez-Brando
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental Medicine (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Adriana Patricia Santiago
- Departamento de Nefrología, Hospital Municipal del Niño, San Justo, Provincia de Buenos Aires, Argentina
| | - Gabriela Alejandra Fiorentino
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental Medicine (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
- Laboratorio, Hospital Municipal del Niño, San Justo, Provincia de Buenos Aires, Argentina
| | - Andrea Mariana Exeni
- Servicio de Nefrología, Hospital Austral, Pilar, Provincia de Buenos Aires, Argentina
| | - Maria Victoria Ramos
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental Medicine (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Marina Sandra Palermo
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental Medicine (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
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17
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Bissinger R, Bhuyan AAM, Qadri SM, Lang F. Oxidative stress, eryptosis and anemia: a pivotal mechanistic nexus in systemic diseases. FEBS J 2018; 286:826-854. [PMID: 30028073 DOI: 10.1111/febs.14606] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/15/2018] [Accepted: 07/18/2018] [Indexed: 12/21/2022]
Abstract
The average lifespan of circulating erythrocytes usually exceeds hundred days. Prior to that, however, erythrocytes may be exposed to oxidative stress in the circulation which could cause injury and trigger their suicidal death or eryptosis. Oxidative stress activates Ca2+ -permeable nonselective cation channels in the cell membrane, thus, stimulating Ca2+ entry and subsequent cell membrane scrambling resulting in phosphatidylserine exposure and activation of Ca2+ -sensitive K+ channels leading to K+ exit, hyperpolarization, Cl- exit, and ultimately cell shrinkage due to loss of KCl and osmotically driven water. While the mechanistic link between oxidative stress and anemia remains ill-defined, several diseases such as diabetes, hepatic failure, malignancy, chronic kidney disease and inflammation have been identified to display both increased oxidative stress as well as eryptosis. Recent compelling evidence suggests that oxidative stress is an important perpetrator in accelerating erythrocyte loss in different systemic conditions and an underlying mechanism for anemia associated with these pathological states. In the present review, we discuss the role of oxidative stress in reducing erythrocyte survival and provide novel insights into the possible use of antioxidants as putative antieryptotic and antianemic agents in a variety of systemic diseases.
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Affiliation(s)
- Rosi Bissinger
- Department of Internal Medicine III, Eberhard-Karls-University Tübingen, Germany
| | - Abdulla Al Mamun Bhuyan
- Department of Vegetative & Clinical Physiology, Institute of Physiology, Eberhard-Karls-University Tübingen, Germany
| | - Syed M Qadri
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.,Centre for Innovation, Canadian Blood Services, Hamilton, ON, Canada
| | - Florian Lang
- Department of Vegetative & Clinical Physiology, Institute of Physiology, Eberhard-Karls-University Tübingen, Germany.,Department of Molecular Medicine II, Heinrich Heine University, Düsseldorf, Germany
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18
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Guerrero-Hue M, Rubio-Navarro A, Sevillano Á, Yuste C, Gutiérrez E, Palomino-Antolín A, Román E, Praga M, Egido J, Moreno JA. Efectos adversos de la acumulación renal de hemoproteínas. Nuevas herramientas terapéuticas. Nefrologia 2018; 38:13-26. [DOI: 10.1016/j.nefro.2017.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 04/21/2017] [Accepted: 05/16/2017] [Indexed: 12/18/2022] Open
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19
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Abrey Recalde MJ, Alvarez RS, Alberto F, Mejias MP, Ramos MV, Fernandez Brando RJ, Bruballa AC, Exeni RA, Alconcher L, Ibarra CA, Amaral MM, Palermo MS. Soluble CD40 Ligand and Oxidative Response Are Reciprocally Stimulated during Shiga Toxin-Associated Hemolytic Uremic Syndrome. Toxins (Basel) 2017; 9:toxins9110331. [PMID: 29068360 PMCID: PMC5705951 DOI: 10.3390/toxins9110331] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 09/29/2017] [Accepted: 10/15/2017] [Indexed: 01/01/2023] Open
Abstract
Shiga toxin (Stx), produced by Escherichia coli, is the main pathogenic factor of diarrhea-associated hemolytic uremic syndrome (HUS), which is characterized by the obstruction of renal microvasculature by platelet-fibrin thrombi. It is well known that the oxidative imbalance generated by Stx induces platelet activation, contributing to thrombus formation. Moreover, activated platelets release soluble CD40 ligand (sCD40L), which in turn contributes to oxidative imbalance, triggering the release of reactive oxidative species (ROS) on various cellular types. The aim of this work was to determine if the interaction between the oxidative response and platelet-derived sCD40L, as consequence of Stx-induced endothelium damage, participates in the pathogenic mechanism during HUS. Activated human glomerular endothelial cells (HGEC) by Stx2 induced platelets to adhere to them. Although platelet adhesion did not contribute to endothelial damage, high levels of sCD40L were released to the medium. The release of sCD40L by activated platelets was inhibited by antioxidant treatment. Furthermore, we found increased levels of sCD40L in plasma from HUS patients, which were also able to trigger the respiratory burst in monocytes in a sCD40L-dependent manner. Thus, we concluded that platelet-derived sCD40L and the oxidative response are reciprocally stimulated during Stx2-associated HUS. This process may contribute to the evolution of glomerular occlusion and the microangiopathic lesions.
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Affiliation(s)
- Maria J Abrey Recalde
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas-Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
| | - Romina S Alvarez
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Instituto de Fisiología y Biofísica "Bernardo Houssay", Facultad de Medicina-Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, 1121 Buenos Aires, Argentina.
| | - Fabiana Alberto
- División Trombosis, Instituto de investigaciones Hematológicas "Mariano R. Castex", Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
| | - Maria P Mejias
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas-Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
| | - Maria V Ramos
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas-Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
| | - Romina J Fernandez Brando
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas-Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
| | - Andrea C Bruballa
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas-Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
| | - Ramon A Exeni
- Departamento de Nefrología, Hospital Municipal del Niño, San Justo, B1754FUD Provincia de Buenos Aires, Argentina.
| | - Laura Alconcher
- Unidad de Nefrourología Infantil. Hospital Interzonal General Dr. José Penna, Bahía Blanca, 8000 Provincia de Buenos Aires, Argentina.
| | - Cristina A Ibarra
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Instituto de Fisiología y Biofísica "Bernardo Houssay", Facultad de Medicina-Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, 1121 Buenos Aires, Argentina.
| | - María M Amaral
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Instituto de Fisiología y Biofísica "Bernardo Houssay", Facultad de Medicina-Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, 1121 Buenos Aires, Argentina.
| | - Marina S Palermo
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas-Academia Nacional de Medicina, 1425 Buenos Aires, Argentina.
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Sant B, Rao PVL, Nagar DP, Pant SC, Bhasker ASB. Evaluation of abrin induced nephrotoxicity by using novel renal injury markers. Toxicon 2017; 131:20-28. [PMID: 28288935 DOI: 10.1016/j.toxicon.2017.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 12/22/2022]
Abstract
Abrin is a potent plant toxin analogous to ricin that is derived from the seeds of Abrus precatorius plant. It belongs to the family of type II ribosome-inactivating proteins and causes cell death by irreversibly inactivating ribosomes through site-specific depurination. In this study we examined the in vivo nephrotoxicity potential of abrin toxin in terms of oxidative stress, inflammation, histopathological changes and biomarkers of kidney injury. Animals were exposed to 0.5 and 1.0 LD50 dose of abrin by intraperitoneal route and observed for 1, 3, and 7 day post-toxin exposure. Depletion of reduced glutathione and increased lipid peroxidation levels were observed in abrin treated mice. In addition, abrin also induced inflammation in the kidneys as observed through expression of MMP-9 and MMP-9/NGAL complex in abrin treated groups by using zymography method. Nephrotoxicity was also evaluated by western blot analysis of kidney injury biomarkers including Clusterin, Cystatin C and NGAL, and their results indicate severity of kidney injury in abrin treated groups. Kidney histology confirmed inflammatory changes due to abrin. The data generated in the present study clearly prove the nephrotoxicity potential of abrin.
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Affiliation(s)
- Bhavana Sant
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474002, India
| | - P V Lakshmana Rao
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474002, India
| | - D P Nagar
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474002, India
| | - S C Pant
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474002, India
| | - A S B Bhasker
- Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Jhansi Road, Gwalior 474002, India.
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Wu SY, Park GY, Kim SH, Hulme J, An SSA. Diminazene aceturate: an antibacterial agent for Shiga-toxin-producing Escherichia coli O157:H7. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:3363-3378. [PMID: 27789937 PMCID: PMC5072558 DOI: 10.2147/dddt.s114832] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The aim of this study was to investigate the bacteriostatic and bactericidal effects of diminazene aceturate (DA) against five strains of pathogenic bacteria and two strains of nonpathogenic bacteria. The results showed that 5 μg/mL of DA suppressed the growth of pathogenic Escherichia coli by as much as 77% compared with the controls. Enterohemorrhagic E. coli EDL933 (an E. coli O157:H7 strain) was the most sensitive to DA with a minimum inhibitory concentration of 20 μg/mL. Additional investigations showed that DA induced the highest level of intracellular reactive oxygen species in EDL933. A positive correlation between the reactive oxygen species levels and DA concentration was demonstrated. DA (5 μg/mL) was also a potent uncoupler, inducing a stationary phase collapse (70%–75%) in both strains of E. coli O157:H7. Further investigation showed that the collapse was due to the NaCl:DA ratio in the broth and was potassium ion dependent. A protease screening assay was conducted to elucidate the underlying mechanism. It was found that at neutral pH, the hydrolysis of H-Asp-pNA increased by a factor of 2–3 in the presence of DA, implying that DA causes dysregulation of the proton motive force and a decrease in cellular pH. Finally, a commercial verotoxin test showed that DA did not significantly increase toxin production in EDL933 and was a suitable antibacterial agent for Shiga-toxin-producing E. coli.
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Affiliation(s)
- Si-Ying Wu
- Department of BioNano Technology, Gachon BioNano Research Institute, Gachon University, Seongnam-si
| | - Gil-Yong Park
- Department of BioNano Technology, Gachon BioNano Research Institute, Gachon University, Seongnam-si
| | - So-Hee Kim
- Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea
| | - John Hulme
- Department of BioNano Technology, Gachon BioNano Research Institute, Gachon University, Seongnam-si
| | - Seong Soo A An
- Department of BioNano Technology, Gachon BioNano Research Institute, Gachon University, Seongnam-si
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Human mannose-binding lectin inhibitor prevents Shiga toxin-induced renal injury. Kidney Int 2016; 90:774-82. [PMID: 27378476 DOI: 10.1016/j.kint.2016.05.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 05/01/2016] [Accepted: 05/05/2016] [Indexed: 01/22/2023]
Abstract
Hemolytic uremic syndrome caused by Shiga toxin-producing Escherichia coli (STEC HUS) is a worldwide endemic problem, and its pathophysiology is not fully elucidated. Here we tested whether the mannose-binding lectin (MBL2), an initiating factor of lectin complement pathway activation, plays a crucial role in STEC HUS. Using novel human MBL2-expressing mice (MBL2 KI) that lack murine Mbls (MBL2(+/+)Mbl1(-/-)Mbl2(-/-)), a novel STEC HUS model consisted of an intraperitoneal injection with Shiga toxin-2 (Stx-2) with or without anti-MBL2 antibody (3F8, intraperitoneal). Stx-2 induced weight loss, anemia, and thrombocytopenia and increased serum creatinine, free serum hemoglobin, and cystatin C levels, but a significantly decreased glomerular filtration rate compared with control/sham mice. Immunohistochemical staining revealed renal C3d deposition and fibrin deposition in glomeruli in Stx-2-injected mice. Treatment with 3F8 completely inhibited serum MBL2 levels and significantly attenuated Stx-2 induced-renal injury, free serum hemoglobin levels, renal C3d, and fibrin deposition and preserved the glomerular filtration rate. Thus, MBL2 inhibition significantly protected against complement activation and renal injury induced by Stx-2. This novel mouse model can be used to study the role of complement, particularly lectin pathway-mediated complement activation, in Stx-2-induced renal injury.
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23
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Álvarez RS, Sacerdoti F, Jancic C, Paton AW, Paton JC, Ibarra C, Amaral MM. Comparative Characterization of Shiga Toxin Type 2 and Subtilase Cytotoxin Effects on Human Renal Epithelial and Endothelial Cells Grown in Monolayer and Bilayer Conditions. PLoS One 2016; 11:e0158180. [PMID: 27336788 PMCID: PMC4918929 DOI: 10.1371/journal.pone.0158180] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 06/10/2016] [Indexed: 11/19/2022] Open
Abstract
Postdiarrheal hemolytic uremic syndrome (HUS) affects children under 5 years old and is responsible for the development of acute and chronic renal failure, particularly in Argentina. This pathology is a complication of Shiga toxin (Stx)-producing Escherichia coli infection and renal damage is attributed to Stx types 1 and 2 (Stx1, Stx2) produced by Escherichia coli O157:H7 and many other STEC serotypes. It has been reported the production of Subtilase cytotoxin (SubAB) by non-O157 STEC isolated from cases of childhood diarrhea. Therefore, it is proposed that SubAB may contribute to HUS pathogenesis. The human kidney is the most affected organ because very Stx-sensitive cells express high amounts of biologically active receptor. In this study, we investigated the effects of Stx2 and SubAB on primary cultures of human glomerular endothelial cells (HGEC) and on a human tubular epithelial cell line (HK-2) in monoculture and coculture conditions. We have established the coculture as a human renal proximal tubule model to study water absorption and cytotoxicity in the presence of Stx2 and SubAB. We obtained and characterized cocultures of HGEC and HK-2. Under basal conditions, HGEC monolayers exhibited the lowest electrical resistance (TEER) and the highest water permeability, while the HGEC/HK-2 bilayers showed the highest TEER and the lowest water permeability. In addition, at times as short as 20-30 minutes, Stx2 and SubAB caused the inhibition of water absorption across HK-2 and HGEC monolayers and this effect was not related to a decrease in cell viability. However, toxins did not have inhibitory effects on water movement across HGEC/HK-2 bilayers. After 72 h, Stx2 inhibited the cell viability of HGEC and HK-2 monolayers, but these effects were attenuated in HGEC/HK-2 bilayers. On the other hand, SubAB cytotoxicity shows a tendency to be attenuated by the bilayers. Our data provide evidence about the different effects of these toxins on the bilayers respect to the monolayers. This in vitro model of communication between human renal microvascular endothelial cells and human proximal tubular epithelial cells is a representative model of the human proximal tubule to study the effects of Stx2 and SubAB related to the development of HUS.
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Affiliation(s)
- Romina S. Álvarez
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Flavia Sacerdoti
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Carolina Jancic
- Laboratorio de Inmunidad Innata, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Adrienne W. Paton
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, University of Adelaide, Adelaide, Australia
| | - James C. Paton
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, University of Adelaide, Adelaide, Australia
| | - Cristina Ibarra
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María M. Amaral
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
- * E-mail:
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Ramos MV, Mejias MP, Sabbione F, Fernandez-Brando RJ, Santiago AP, Amaral MM, Exeni R, Trevani AS, Palermo MS. Induction of Neutrophil Extracellular Traps in Shiga Toxin-Associated Hemolytic Uremic Syndrome. J Innate Immun 2016; 8:400-11. [PMID: 27230920 DOI: 10.1159/000445770] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 03/24/2016] [Indexed: 01/17/2023] Open
Abstract
Hemolytic uremic syndrome (HUS), a vascular disease characterized by hemolytic anemia, thrombocytopenia, and acute renal failure, is caused by enterohemorrhagic Shiga toxin (Stx)-producing bacteria, which mainly affect children. Besides Stx, the inflammatory response mediated by neutrophils (PMN) is essential to HUS evolution. PMN can release neutrophil extracellular traps (NET) composed of DNA, histones, and other proteins. Since NET are involved in infectious and inflammatory diseases, the aim of this work was to investigate the contribution of NET to HUS. Plasma from HUS patients contained increased levels of circulating free-DNA and nucleosomes in comparison to plasma from healthy children. Neutrophils from HUS patients exhibited a greater capacity to undergo spontaneous NETosis. NET activated human glomerular endothelial cells, stimulating secretion of the proinflammatory cytokines IL-6 and IL-8. Stx induced PMN activation as judged by its ability to trigger reactive oxygen species production, increase CD11b and CD66b expression, and induce NETosis in PMN from healthy donors. During HUS, NET can contribute to the inflammatory response and thrombosis in the microvasculature and thus to renal failure. Intervention strategies to inhibit inflammatory mechanisms mediated by PMN, such as NETosis, could have a potential therapeutic impact towards amelioration of the severity of HUS.
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Keir LS, Langman CB. Complement and the kidney in the setting of Shiga-toxin hemolytic uremic syndrome, organ transplantation, and C3 glomerulonephritis. Transfus Apher Sci 2016; 54:203-11. [PMID: 27156109 DOI: 10.1016/j.transci.2016.04.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To review the role of complement in glomerular pathologies focusing on thrombotic microangiopathies (TMA) caused by Shiga toxin (Stx) and organ transplantation associated hemolytic uremic syndrome (HUS) as well as C3 glomerulopathy (C3G). METHODS Examination of literature discussing TMA associated with Stx HUS, transplantation related HUS and C3G. RESULTS There is an emerging role for complement biology in the renal glomerulus where its inappropriate over-activation is integral to several diseases. Stx HUS patients show evidence of complement activation and the toxin itself can activate complement and inhibit its normal regulation. However, therapeutic complement blockade has not yet proven effective in all circumstances. This may be partly related to late use and a clinical trial could be warranted. Organ transplantation associated HUS has carried a poor prognosis. While case reports supporting the use of complement inhibition exist, there has not been a formal trial. Complement activation in C3G is established but again treatment with complement inhibition has failed to be uniformly beneficial. Here, too, a clinical trial may help determine which subgroup of patients should be treated with these agents. CONCLUSION Complement plays an important role in the glomerulus but more work is needed to fully understand how it contributes to normal function and pathology. This will help direct appropriate therapy in these diseases.
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Affiliation(s)
- Lindsay S Keir
- Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Division of Kidney Diseases, The Ann and Robert H Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Craig B Langman
- Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Division of Kidney Diseases, The Ann and Robert H Lurie Children's Hospital of Chicago, Chicago, IL, USA.
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Timmons RM, Webb CB. Vitamin E supplementation fails to impact measures of oxidative stress or the anaemia of feline chronic kidney disease: a randomised, double-blinded placebo control study. Vet Med Sci 2016; 2:117-124. [PMID: 29067185 PMCID: PMC5645861 DOI: 10.1002/vms3.21] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 11/27/2015] [Accepted: 12/09/2015] [Indexed: 01/19/2023] Open
Abstract
This study was designed to test the hypothesis that supplementation with vitamin E, an antioxidant, in cats with chronic kidney disease (CKD), would reduce oxidative stress and its impact on RBC membrane fragility, resulting in these cats maintaining a greater packed cell volume (PCV) compared with CKD cats not receiving supplementation. Thirty‐six cats with CKD were randomly assigned to receive either daily vitamin E or a placebo for 3 months in a double‐blinded study design. History and physical examination, blood pressure, complete blood count (CBC), PCV, biochemical profile and urinalysis (UA) were determined. Parameters of oxidative stress and osmotic fragility were measured. Cats were administered vitamin E or placebo once daily for 3 months. Cats were then reassessed and the diagnostics were repeated. Twenty‐four cats completed the study, 11 in the vitamin E group and 13 in the placebo group. There were no significant differences between the two groups at the start, or upon completion of the study with regard to biochemical parameters, oxidative stress, erythrocyte osmotic fragility or PCV. None of these parameters changed significantly in either group over the treatment period. Daily supplementation with 30 IU of vitamin E did not affect the measures of oxidative stress or the anaemia seen in cats with CKD.
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Affiliation(s)
- Rebecca M Timmons
- Department of Clinical SciencesCollege of Veterinary Medicine and Biomedical SciencesColorado State UniversityFort CollinsCO80523
| | - Craig B Webb
- Department of Clinical SciencesCollege of Veterinary Medicine and Biomedical SciencesColorado State UniversityFort CollinsCO80523
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Betzen C, Plotnicki K, Fathalizadeh F, Pappan K, Fleming T, Bielaszewska M, Karch H, Tönshoff B, Rafat N. Shiga Toxin 2a-Induced Endothelial Injury in Hemolytic Uremic Syndrome: A Metabolomic Analysis. J Infect Dis 2015; 213:1031-40. [PMID: 26582960 DOI: 10.1093/infdis/jiv540] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 11/03/2015] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Endothelial dysfunction plays a pivotal role in the pathogenesis of postenteropathic hemolytic uremic syndrome (HUS), most commonly caused by Shiga toxin (Stx)-producing strains of Escherichia coli. METHODS To identify new treatment targets, we performed a metabolomic high-throughput screening to analyze the effect of Stx2a, the major Stx type associated with HUS, on human renal glomerular endothelial cells (HRGEC) and umbilical vein endothelial cells (HUVEC). Cells were treated either with sensitizing tumor necrosis factor α (TNF-α) or Stx2a, a sequence of both or remained untreated. RESULTS We identified 341 metabolites by combined liquid chromatography/tandem mass spectrometry and gas chromatography/mass spectrometry. Both cell lines exhibited distinct metabolic reaction profiles but shared elevated levels of free fatty acids. Stx2a predominantly altered the nicotinamide adenine dinucleotide (NAD) cofactor pathway and the inflammation-modulating eicosanoid pathway, which are associated with lipid metabolism. In HRGEC, Stx2a strongly diminished NAD derivatives, leading to depletion of the energy substrate acetyl coenzyme A and the antioxidant glutathione. HUVEC responded to TNF-α and Stx2a by increasing production of the counteracting eicosanoids prostaglandin I2, E1, E2, and A2, while in HRGEC only more prostaglandin I2 was detected. CONCLUSIONS We conclude that disruption of energy metabolism and depletion of glutathione contributes to Stx-induced injury of the renal endothelium and that the inflammatory response to Stx is highly cell-type specific.
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Affiliation(s)
- Christian Betzen
- Department of Pediatrics I, University Children's Hospital Heidelberg Division of Functional Genome Analysis, German Cancer Research Center
| | - Kathrin Plotnicki
- Department of Pediatrics I, University Children's Hospital Heidelberg
| | | | | | - Thomas Fleming
- Department of Medicine I and Clinical Chemistry, University Hospital Heidelberg
| | | | - Helge Karch
- Institute for Hygiene, University of Münster, Germany
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg
| | - Neysan Rafat
- Department of Pediatrics I, University Children's Hospital Heidelberg
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Abstract
Hemolytic-uremic syndrome (HUS) is a thrombotic microangiopathy that is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and renal failure. Excess complement activation underlies atypical HUS and is evident in Shiga toxin-induced HUS (STEC-HUS). This Spotlight focuses on new knowledge of the role of Escherichia coli-derived toxins and polyphosphate in modulating complement and coagulation, and how they affect disease progression and response to treatment. Such new insights may impact on current and future choices of therapies for STEC-HUS.
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Triggers, inhibitors, mechanisms, and significance of eryptosis: the suicidal erythrocyte death. BIOMED RESEARCH INTERNATIONAL 2015; 2015:513518. [PMID: 25821808 PMCID: PMC4364016 DOI: 10.1155/2015/513518] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 01/12/2015] [Accepted: 01/15/2015] [Indexed: 12/13/2022]
Abstract
Suicidal erythrocyte death or eryptosis is characterized by erythrocyte shrinkage, cell membrane blebbing, and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca(2+) entry, ceramide formation, stimulation of caspases, calpain activation, energy depletion, oxidative stress, and dysregulation of several kinases. Eryptosis is triggered by a wide variety of xenobiotics. It is inhibited by several xenobiotics and endogenous molecules including NO and erythropoietin. The susceptibility of erythrocytes to eryptosis increases with erythrocyte age. Phosphatidylserine exposing erythrocytes adhere to the vascular wall by binding to endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor for phosphatidylserine and oxidized low density lipoprotein (CXCL16). Phosphatidylserine exposing erythrocytes are further engulfed by phagocytosing cells and are thus rapidly cleared from circulating blood. Eryptosis eliminates infected or defective erythrocytes thus counteracting parasitemia in malaria and preventing detrimental hemolysis of defective cells. Excessive eryptosis, however, may lead to anemia and may interfere with microcirculation. Enhanced eryptosis contributes to the pathophysiology of several clinical disorders including metabolic syndrome and diabetes, malignancy, cardiac and renal insufficiency, hemolytic uremic syndrome, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Facilitating or inhibiting eryptosis may be a therapeutic option in those disorders.
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Lang E, Lang F. Mechanisms and pathophysiological significance of eryptosis, the suicidal erythrocyte death. Semin Cell Dev Biol 2015; 39:35-42. [PMID: 25636585 DOI: 10.1016/j.semcdb.2015.01.009] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 01/14/2015] [Accepted: 01/19/2015] [Indexed: 12/11/2022]
Abstract
Eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling, is stimulated by Ca(2+) entry through Ca(2+)-permeable, PGE2-activated cation channels, by ceramide, caspases, calpain, complement, hyperosmotic shock, energy depletion, oxidative stress, and deranged activity of several kinases (e.g. AMPK, GK, PAK2, CK1α, JAK3, PKC, p38-MAPK). Eryptosis is triggered by intoxication, malignancy, hepatic failure, diabetes, chronic renal insufficiency, hemolytic uremic syndrome, dehydration, phosphate depletion, fever, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Eryptosis may precede and protect against hemolysis but by the same token result in anemia and deranged microcirculation.
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Affiliation(s)
- Elisabeth Lang
- Department of Physiology, University of Tübingen, Gmelinstr. 5, 72076 Tübingen, Germany
| | - Florian Lang
- Department of Physiology, University of Tübingen, Gmelinstr. 5, 72076 Tübingen, Germany.
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Cabrera G, Fernández-Brando RJ, Abrey-Recalde MJ, Baschkier A, Pinto A, Goldstein J, Zotta E, Meiss R, Rivas M, Palermo MS. Retinoid levels influence enterohemorrhagic Escherichia coli infection and Shiga toxin 2 susceptibility in mice. Infect Immun 2014; 82:3948-57. [PMID: 25001607 PMCID: PMC4187814 DOI: 10.1128/iai.02191-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) is a food-borne pathogen that produces Shiga toxin (Stx) and causes hemorrhagic colitis. Under some circumstances, Stx produced within the intestinal tract enters the bloodstream, leading to systemic complications that may cause the potentially fatal hemolytic-uremic syndrome. Although retinoids like vitamin A (VA) and retinoic acid (RA) are beneficial to gut integrity and the immune system, the effect of VA supplementation on gastrointestinal infections of different etiologies has been controversial. Thus, the aim of this work was to study the influence of different VA status on the outcome of an EHEC intestinal infection in mice. We report that VA deficiency worsened the intestinal damage during EHEC infection but simultaneously improved survival. Since death is associated mainly with Stx toxicity, Stx was intravenously inoculated to analyze whether retinoid levels affect Stx susceptibility. Interestingly, while VA-deficient (VA-D) mice were resistant to a lethal dose of Stx2, RA-supplemented mice were more susceptible to it. Given that peripheral blood polymorphonuclear cells (PMNs) are known to potentiate Stx2 toxicity, we studied the influence of retinoid levels on the absolute number and function of PMNs. We found that VA-D mice had decreased PMN numbers and a diminished capacity to produce reactive oxygen species, while RA supplementation had the opposite effect. These results are in line with the well-known function of retinoids in maintaining the homeostasis of the gut but support the idea that they have a proinflammatory effect by acting, in part, on the PMN population.
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Affiliation(s)
- Gabriel Cabrera
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Romina J Fernández-Brando
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - María Jimena Abrey-Recalde
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Ariela Baschkier
- Servicio de Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas-ANLIS Dr. Carlos Malbrán, Buenos Aires, Argentina
| | - Alipio Pinto
- Laboratorio de Neurofisiología, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Jorge Goldstein
- Laboratorio de Neurofisiología, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Elsa Zotta
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Roberto Meiss
- Departamento de Patología, Centro de Estudios Oncológicos, Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Marta Rivas
- Servicio de Fisiopatogenia, Instituto Nacional de Enfermedades Infecciosas-ANLIS Dr. Carlos Malbrán, Buenos Aires, Argentina
| | - Marina S Palermo
- Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX) (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
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Abstract
SIGNIFICANCE Eryptosis, the suicidal erythrocyte death, is characterized by cell shrinkage, membrane blebbing, and phosphatidylserine translocation to the outer membrane leaflet. Phosphatidylserine at the erythrocyte surface binds endothelial CXCL16/SR-PSOX (CXC-Motiv-Chemokin-16/Scavenger-receptor-for-phosphatidylserine-and-oxidized-low-density-lipoprotein) and fosters engulfment of affected erythrocytes by phagocytosing cells. Eryptosis serves to eliminate infected or defective erythrocytes, but excessive eryptosis may lead to anemia and may interfere with microcirculation. Clinical conditions with excessive eryptosis include diabetes, chronic renal failure, hemolytic uremic syndrome, sepsis, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, glutamate cysteine ligase modulator deficiency, and Wilson's disease. RECENT ADVANCES Eryptosis is triggered by a wide variety of xenobiotics and other injuries such as oxidative stress. Signaling of eryptosis includes prostaglandin E₂ formation with subsequent activation of Ca(2+)-permeable cation channels, Ca(2+) entry, activation of Ca(2+)-sensitive K(+) channels, and cell membrane scrambling, as well as phospholipase A2 stimulation with release of platelet-activating factor, sphingomyelinase activation, and ceramide formation. Eryptosis may involve stimulation of caspases and calpain with subsequent degradation of the cytoskeleton. It is regulated by AMP-activated kinase, cGMP-dependent protein kinase, Janus-activated kinase 3, casein kinase 1α, p38 kinase, and p21-activated kinase 2. It is inhibited by erythropoietin, antioxidants, and further small molecules. CRITICAL ISSUES It remains uncertain for most disorders whether eryptosis is rather beneficial because it precedes and thus prevents hemolysis or whether it is harmful because of induction of anemia and impairment of microcirculation. FUTURE DIRECTIONS This will address the significance of eryptosis, further mechanisms underlying eryptosis, and additional pharmacological tools fostering or inhibiting eryptosis.
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Affiliation(s)
- Florian Lang
- Department of Physiology, University of Tübingen , Tübingen, Germany
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L-arginine/NO pathway is altered in children with haemolytic-uraemic syndrome (HUS). OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:203512. [PMID: 24757496 PMCID: PMC3976927 DOI: 10.1155/2014/203512] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 02/11/2014] [Indexed: 12/13/2022]
Abstract
The haemolytic uraemic syndrome (HUS) is the most frequent cause of acute renal failure in childhood. We investigated L-arginine/NO pathway in 12 children with typical HUS and 12 age-matched healthy control subjects. Nitrite and nitrate, the major NO metabolites in plasma and urine, asymmetric dimethylarginine (ADMA) in plasma and urine, and dimethylamine (DMA) in urine were determined by GC-MS and GC-MS/MS techniques. Urinary measurements were corrected for creatinine excretion. Plasma nitrate was significantly higher in HUS patients compared to healthy controls
(P = 0.021), whereas urine nitrate was borderline lower in HUS patients compared to healthy controls (P = 0.24). ADMA plasma concentrations were insignificantly lower, but urine ADMA levels were significantly lower in the HUS patients (P = 0.019). Urinary DMA was not significantly elevated. In HUS patients, nitrate (R = 0.91) but not nitrite, L-arginine, or ADMA concentrations in plasma correlated with free haemoglobin concentration. Our results suggest that both NO production and ADMA synthesis are decreased in children with typical HUS. We hypothesize that in the circulation of children with HUS a vicious circle between the L-arginine/NO pathway and free haemoglobin-mediated oxidative stress exists. Disruption of this vicious circle by drugs that release NO and/or sulphydryl groups-containing drugs may offer new therapeutic options in HUS.
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Ibarra C, Amaral MM, Palermo MS. Advances in pathogenesis and therapy of hemolytic uremic syndrome caused by Shiga toxin-2. IUBMB Life 2013; 65:827-35. [PMID: 24014500 DOI: 10.1002/iub.1206] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 08/06/2013] [Indexed: 11/12/2022]
Abstract
Shiga toxin (Stx) producing Escherichia coli (STEC) is responsible to bloody diarrhea (hemorrhagic colitis) and the hemolytic uremic syndrome (HUS). STEC strains carry inducible lambda phages integrated into their genomes that encode Stx 1 and/or 2, with several allelic variants each one. O157:H7 is the serotype that was documented in the vast majority of HUS cases although non-O157 serotypes have been increasingly reported to account for HUS cases. However, the outbreak that occurred in central Europe during late spring of 2011 showed that the pathogen was E. coli O104:H4. More than 4,000 persons were infected mainly in Germany, and it produced more than 900 cases of HUS resulting in 54 deaths. E. coli O104:H4 is a hybrid organism that combines some of the virulence genes of STEC and enteroaggregative E. coli specially production of Stx2 and the adherence mechanisms to intestinal epithelium. The differences in the epidemiology and presentation of E. coli pathogen meant a challenge for public health and scientific research to increase the knowledge of HUS-pathophysiology and to improve available therapies to treat HUS.
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Affiliation(s)
- Cristina Ibarra
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad, de Buenos Aires, Argentina
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