1
|
Hof S, Lingens L, Michels M, Marcus C, Kuebart A, Herminghaus A, Bauer I, Picker O, Truse R, Vollmer C. Local carbachol application induces oral microvascular recruitment and improves gastric tissue oxygenation during hemorrhagic shock in dogs. Front Immunol 2024; 15:1369617. [PMID: 38566995 PMCID: PMC10985194 DOI: 10.3389/fimmu.2024.1369617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/04/2024] [Indexed: 04/04/2024] Open
Abstract
Introduction Hemorrhagic shock is characterized by derangements of the gastrointestinal microcirculation. Topical therapy with nitroglycerine or iloprost improves gastric tissue oxygenation but not regional perfusion, probably due to precapillary adrenergic innervation. Therefore, this study was designed to investigate the local effect of the parasympathomimetic carbachol alone and in combination with either nitroglycerine or iloprost on gastric and oral microcirculation during hemorrhagic shock. Methods In a cross-over design five female foxhounds were repeatedly randomized into six experimental groups. Carbachol, or carbachol in combination with either nitroglycerine or iloprost were applied topically to the oral and gastric mucosa. Saline, nitroglycerine, or iloprost application alone served as control groups. Then, a fixed-volume hemorrhage was induced by arterial blood withdrawal followed by blood retransfusion after 1h of shock. Gastric and oral microcirculation was determined using reflectance spectrophotometry and laser Doppler flowmetry. Oral microcirculation was visualized with videomicroscopy. Statistics: 2-way-ANOVA for repeated measurements and Bonferroni post-hoc analysis (mean ± SEM; p < 0.05). Results The induction of hemorrhage led to a decrease of gastric and oral tissue oxygenation, that was ameliorated by local carbachol and nitroglycerine application at the gastric mucosa. The sole use of local iloprost did not improve gastric tissue oxygenation but could be supplemented by local carbachol treatment. Adding carbachol to nitroglycerine did not further increase gastric tissue oxygenation. Gastric microvascular blood flow remained unchanged in all experimental groups. Oral microvascular blood flow, microvascular flow index and total vessel density decreased during shock. Local carbachol supply improved oral vessel density during shock and oral microvascular flow index in the late course of hemorrhage. Conclusion The specific effect of shifting the autonomous balance by local carbachol treatment on microcirculatory variables varies between parts of the gastrointestinal tract. Contrary to our expectations, the improvement of gastric tissue oxygenation by local carbachol or nitroglycerine application was not related to increased microvascular perfusion. When carbachol is used in combination with local vasodilators, the additional effect on gastric tissue oxygenation depends on the specific drug combination. Therefore, modulation of tissue oxygen consumption, mitochondrial function or alterations in regional blood flow distribution should be investigated.
Collapse
Affiliation(s)
- Stefan Hof
- Department of Anesthesiology, Duesseldorf University Hospital, Duesseldorf, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
2
|
Wang G, Lian H, Zhang H, Wang X. Microcirculation and Mitochondria: The Critical Unit. J Clin Med 2023; 12:6453. [PMID: 37892591 PMCID: PMC10607663 DOI: 10.3390/jcm12206453] [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: 08/23/2023] [Revised: 09/22/2023] [Accepted: 10/08/2023] [Indexed: 10/29/2023] Open
Abstract
Critical illness is often accompanied by a hemodynamic imbalance between macrocirculation and microcirculation, as well as mitochondrial dysfunction. Microcirculatory disorders lead to abnormalities in the supply of oxygen to tissue cells, while mitochondrial dysfunction leads to abnormal energy metabolism and impaired tissue oxygen utilization, making these conditions important pathogenic factors of critical illness. At the same time, there is a close relationship between the microcirculation and mitochondria. We introduce here the concept of a "critical unit", with two core components: microcirculation, which mainly comprises the microvascular network and endothelial cells, especially the endothelial glycocalyx; and mitochondria, which are mainly involved in energy metabolism but perform other non-negligible functions. This review also introduces several techniques and devices that can be utilized for the real-time synchronous monitoring of the microcirculation and mitochondria, and thus critical unit monitoring. Finally, we put forward the concepts and strategies of critical unit-guided treatment.
Collapse
Affiliation(s)
- Guangjian Wang
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China; (G.W.); (H.Z.)
| | - Hui Lian
- Department of Health Care, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China;
| | - Hongmin Zhang
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China; (G.W.); (H.Z.)
| | - Xiaoting Wang
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China; (G.W.); (H.Z.)
| |
Collapse
|
3
|
Chiscano-Camón L, Plata-Menchaca E, Ruiz-Rodríguez JC, Ferrer R. Fisiopatología del shock séptico. Med Intensiva 2022. [DOI: 10.1016/j.medin.2022.03.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
4
|
Mallat J, Rahman N, Hamed F, Hernandez G, Fischer MO. Pathophysiology, mechanisms, and managements of tissue hypoxia. Anaesth Crit Care Pain Med 2022; 41:101087. [PMID: 35462083 DOI: 10.1016/j.accpm.2022.101087] [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: 12/29/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/01/2022]
Abstract
Oxygen is needed to generate aerobic adenosine triphosphate and energy that is required to support vital cellular functions. Oxygen delivery (DO2) to the tissues is determined by convective and diffusive processes. The ability of the body to adjust oxygen extraction (ERO2) in response to changes in DO2 is crucial to maintain constant tissue oxygen consumption (VO2). The capability to increase ERO2 is the result of the regulation of the circulation and the effects of the simultaneous activation of both central and local factors. The endothelium plays a crucial role in matching tissue oxygen supply to demand in situations of acute drop in tissue oxygenation. Tissue oxygenation is adequate when tissue oxygen demand is met. When DO2 is severely compromised, a critical DO2 value is reached below which VO2 falls and becomes dependent on DO2, resulting in tissue hypoxia. The different mechanisms of tissue hypoxia are circulatory, anaemic, and hypoxic, characterised by a diminished DO2 but preserved capacity of increasing ERO2. Cytopathic hypoxia is another mechanism of tissue hypoxia that is due to impairment in mitochondrial respiration that can be observed in septic conditions with normal overall DO2. Sepsis induces microcirculatory alterations with decreased functional capillary density, increased number of stopped-flow capillaries, and marked heterogeneity between the areas with large intercapillary distance, resulting in impairment of the tissue to extract oxygen and to satisfy the increased tissue oxygen demand, leading to the development of tissue hypoxia. Different therapeutic approaches exist to increase DO2 and improve microcirculation, such as fluid therapy, transfusion, vasopressors, inotropes, and vasodilators. However, the effects of these agents on microcirculation are quite variable.
Collapse
Affiliation(s)
- Jihad Mallat
- Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates; Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA; Normandy University, UNICAEN, ED 497, Caen, France.
| | - Nadeem Rahman
- Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Fadi Hamed
- Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Glenn Hernandez
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontifcia Universidad Católica de Chile, Santiago, Chile
| | - Marc-Olivier Fischer
- Department of Anaesthesiology-Resuscitation and Perioperative Medicine, Normandy University, UNICAEN, Caen University Hospital, Normandy, Caen, France
| |
Collapse
|
5
|
Chiscano-Camón L, Plata-Menchaca E, Ruiz-Rodríguez JC, Ferrer R. [Pathophysiology of septic shock]. Med Intensiva 2022; 46 Suppl 1:1-13. [PMID: 38341256 DOI: 10.1016/j.medine.2022.03.010] [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: 02/01/2022] [Accepted: 03/20/2022] [Indexed: 02/12/2024]
Abstract
Sepsis and septic shock result from an inadequate host response to an infection, which causes organ dysfunction. The progression of this condition is manifested by the occurrence of successive clinical stages, resulting from the systemic inflammatory response secondary to the activation of different inflammatory mediators, leading to organ dysfunction. There is a high burden of evidence on the role of endotoxin in the pathogenesis of sepsis and its crucial role in triggering the inflammatory response in sepsis caused by gram-negative bacteria. The coagulation cascade activation in sepsis patients is part of the host's adaptive immune response to infection. The endothelium is the main target in sepsis, which is metabolically active and can.
Collapse
Affiliation(s)
- Luis Chiscano-Camón
- Servicio de Medicina Intensiva, Hospital Universitario Vall d'Hebron, Barcelona, España; Grupo de Investigación Sepsis Organ Dysfunction and Resuscitation (SODIR), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Barcelona, España; Departament de Medicina. Universitat Autònoma de Barcelona. Barcelona. España
| | - Erika Plata-Menchaca
- Servicio de Medicina Intensiva, Hospital Universitario Vall d'Hebron, Barcelona, España; Grupo de Investigación Sepsis Organ Dysfunction and Resuscitation (SODIR), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Barcelona, España
| | - Juan Carlos Ruiz-Rodríguez
- Servicio de Medicina Intensiva, Hospital Universitario Vall d'Hebron, Barcelona, España; Grupo de Investigación Sepsis Organ Dysfunction and Resuscitation (SODIR), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Barcelona, España; Departament de Medicina. Universitat Autònoma de Barcelona. Barcelona. España
| | - Ricard Ferrer
- Servicio de Medicina Intensiva, Hospital Universitario Vall d'Hebron, Barcelona, España; Grupo de Investigación Sepsis Organ Dysfunction and Resuscitation (SODIR), Vall d'Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d'Hebron, Barcelona, España; Departament de Medicina. Universitat Autònoma de Barcelona. Barcelona. España.
| |
Collapse
|
6
|
Ghadimi K, Cappiello J, Cooter-Wright M, Haney JC, Reynolds JM, Bottiger BA, Klapper JA, Levy JH, Hartwig MG. Inhaled Pulmonary Vasodilator Therapy in Adult Lung Transplant: A Randomized Clinical Trial. JAMA Surg 2021; 157:e215856. [PMID: 34787647 DOI: 10.1001/jamasurg.2021.5856] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Importance Inhaled nitric oxide (iNO) is commonly administered for selectively inhaled pulmonary vasodilation and prevention of oxidative injury after lung transplant (LT). Inhaled epoprostenol (iEPO) has been introduced worldwide as a cost-saving alternative to iNO without high-grade evidence for this indication. Objective To investigate whether the use of iEPO will lead to similar rates of severe/grade 3 primary graft dysfunction (PGD-3) after adult LT when compared with use of iNO. Design, Setting, and Participants This health system-funded, randomized, blinded (to participants, clinicians, data managers, and the statistician), parallel-designed, equivalence clinical trial included 201 adult patients who underwent single or bilateral LT between May 30, 2017, and March 21, 2020. Patients were grouped into 5 strata according to key prognostic clinical features and randomized per stratum to receive either iNO or iEPO at the time of LT via 1:1 treatment allocation. Interventions Treatment with iNO or iEPO initiated in the operating room before lung allograft reperfusion and administered continously until cessation criteria met in the intensive care unit (ICU). Main Outcomes and Measures The primary outcome was PGD-3 development at 24, 48, or 72 hours after LT. The primary analysis was for equivalence using a two one-sided test (TOST) procedure (90% CI) with a margin of 19% for between-group PGD-3 risk difference. Secondary outcomes included duration of mechanical ventilation, hospital and ICU lengths of stay, incidence and severity of acute kidney injury, postoperative tracheostomy placement, and in-hospital, 30-day, and 90-day mortality rates. An intention-to-treat analysis was performed for the primary and secondary outcomes, supplemented by per-protocol analysis for the primary outcome. Results A total of 201 randomized patients met eligibility criteria at the time of LT (129 men [64.2%]). In the intention-to-treat population, 103 patients received iEPO and 98 received iNO. The primary outcome occurred in 46 of 103 patients (44.7%) in the iEPO group and 39 of 98 (39.8%) in the iNO group, leading to a risk difference of 4.9% (TOST 90% CI, -6.4% to 16.2%; P = .02 for equivalence). There were no significant between-group differences for secondary outcomes. Conclusions and Relevance Among patients undergoing LT, use of iEPO was associated with similar risks for PGD-3 development and other postoperative outcomes compared with the use of iNO. Trial Registration ClinicalTrials.gov identifier: NCT03081052.
Collapse
Affiliation(s)
- Kamrouz Ghadimi
- Department of Anesthesiology & Critical Care, Duke University School of Medicine, Durham, North Carolina
| | - Jhaymie Cappiello
- Department of Respiratory Care Services, Duke University Medical Center, Durham, North Carolina
| | - Mary Cooter-Wright
- Department of Anesthesiology & Critical Care, Duke University School of Medicine, Durham, North Carolina
| | - John C Haney
- Department of Surgery, Thoracic Transplant Surgery, Duke University School of Medicine, Durham, North Carolina
| | - John M Reynolds
- Department of Medicine, Transplant Pulmonology, Duke University School of Medicine, Durham, North Carolina
| | - Brandi A Bottiger
- Department of Anesthesiology & Critical Care, Duke University School of Medicine, Durham, North Carolina
| | - Jacob A Klapper
- Department of Surgery, Thoracic Transplant Surgery, Duke University School of Medicine, Durham, North Carolina
| | - Jerrold H Levy
- Department of Anesthesiology & Critical Care, Duke University School of Medicine, Durham, North Carolina
| | - Matthew G Hartwig
- Department of Surgery, Thoracic Transplant Surgery, Duke University School of Medicine, Durham, North Carolina
| | | |
Collapse
|
7
|
Ding M, Tolbert E, Birkenbach M, Akhlaghi F, Gohh R, Ghonem NS. Treprostinil, a prostacyclin analog, ameliorates renal ischemia-reperfusion injury: preclinical studies in a rat model of acute kidney injury. Nephrol Dial Transplant 2021; 36:257-266. [PMID: 33156922 DOI: 10.1093/ndt/gfaa236] [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] [Received: 01/06/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Renal ischemia-reperfusion injury (IRI) is a major factor causing acute kidney injury (AKI). No pharmacological treatments for prevention or amelioration of I/R-induced renal injury are available. Here we investigate the protective effects of treprostinil, a prostacyclin analog, against renal IRI in vivo. METHODS Male Sprague Dawley rats were subjected to bilateral renal ischemia (45 min) followed by reperfusion for 1-168 h. Treprostinil (100 ng/kg/min) or placebo was administered subcutaneously for 18-24 h before ischemia. RESULTS Treatment with treprostinil both significantly reduced peak elevation and accelerated the return to baseline levels for serum creatinine and blood urea nitrogen versus I/R-placebo animals following IRI. I/R-treprostinil animals exhibited reduced histopathological features of tubular epithelial injury versus I/R-placebo animals. IRI resulted in a marked induction of messenger RNA coding for kidney injury biomarkers, kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin and for pro-inflammatory cytokines chemokine (C-C motif) ligand 2, interleukin 1β, interleukin 6 and intracellular adhesion molecular 1 in animals treated with placebo only relative to sham controls. Upregulation of expression of all these genes was significantly suppressed by treprostinil. Treprostinil significantly suppressed the elevation in renal lipid peroxidation found in the I/R-placebo group at 1-h post-reperfusion. In addition, renal protein expression of cleaved poly(ADP-ribose) polymerase 1 and caspase-3, -8 and -9 in I/R-placebo animals was significantly inhibited by treprostinil. CONCLUSIONS This study demonstrates the efficacy of treprostinil in ameliorating I/R-induced AKI in rats by significantly improving renal function early post-reperfusion and by inhibiting renal inflammation and tubular epithelial apoptosis. Importantly, these data suggest that treprostinil has the potential to serve as a therapeutic agent to protect the kidney against IRI in vivo.
Collapse
Affiliation(s)
- Meiwen Ding
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, USA
| | - Evelyn Tolbert
- Division of Renal Disease, Department of Medicine, Warren Alpert School of Medicine, Brown University, Providence, RI, USA
| | - Mark Birkenbach
- Department of Pathology, Warren Alpert School of Medicine, Brown University, Providence, RI, USA
| | - Fatemeh Akhlaghi
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, USA
| | - Reginald Gohh
- Division of Organ Transplantation, Rhode Island Hospital, Warren Alpert School of Medicine, Brown University, Providence, RI, USA
| | - Nisanne S Ghonem
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, USA
| |
Collapse
|
8
|
Song A, Zhang C, Meng X. Mechanism and application of metformin in kidney diseases: An update. Biomed Pharmacother 2021; 138:111454. [PMID: 33714781 DOI: 10.1016/j.biopha.2021.111454] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/26/2021] [Accepted: 02/27/2021] [Indexed: 01/08/2023] Open
Abstract
Metformin is an oral antihyperglycemic drug widely used to treat type 2 diabetes mellitus (T2DM), acting via indirect activation of 5' Adenosine monophosphate-activated Protein Kinase (AMPK). Beyond the anti-diabetic effect, accumulative pieces of evidence have revealed that metformin also everts a beneficial effect in diverse kidney diseases. In various acute kidney diseases (AKI) animal models, metformin protects renal tubular cells from inflammation, apoptosis, reactive oxygen stress (ROS), endoplasmic reticulum (ER) stress, epithelial-mesenchymal transition (EMT) via AMPK activation. In diabetic kidney disease (DKD), metformin also alleviates podocyte loss, mesangial cells apoptosis, and tubular cells senescence through AMPK-mediated signaling pathways. Besides, metformin inhibits cystic fibrosis transmembrane conductance regulator (CFTR)-mediated fluids secretion and the mammalian target of rapamycin (mTOR)-involved cyst formation negatively regulated by AMPK in autosomal dominant polycystic kidney disease (APDKD). Furthermore, metformin also contributes to the alleviation of urolithiasis and renal cell carcinoma (RCC). As the common pathway for chronic kidney disease (CKD) progressing towards end-stage renal disease (ESRD), renal fibrosis is ameliorated by metformin, to a great extent dependent on AMPK activation. However, clinical data are not always consistent with preclinical data, some clinical investigations showed the unmeaningful even detrimental effect of metformin on T2DM patients with kidney diseases. Most importantly, metformin-associated lactic acidosis (MALA) is a vital issue restricting the application of metformin. Thus, we conclude the application of metformin in kidney diseases and uncover the underlying molecular mechanisms in this review.
Collapse
Affiliation(s)
- Anni Song
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Chun Zhang
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xianfang Meng
- Department of Neurobiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
| |
Collapse
|
9
|
Merz T, Denoix N, Huber-Lang M, Singer M, Radermacher P, McCook O. Microcirculation vs. Mitochondria-What to Target? Front Med (Lausanne) 2020; 7:416. [PMID: 32903633 PMCID: PMC7438707 DOI: 10.3389/fmed.2020.00416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 06/29/2020] [Indexed: 01/02/2023] Open
Abstract
Circulatory shock is associated with marked disturbances of the macro- and microcirculation and flow heterogeneities. Furthermore, a lack of tissue adenosine trisphosphate (ATP) and mitochondrial dysfunction are directly associated with organ failure and poor patient outcome. While it remains unclear if microcirculation-targeted resuscitation strategies can even abolish shock-induced flow heterogeneity, mitochondrial dysfunction and subsequently diminished ATP production could still lead to organ dysfunction and failure even if microcirculatory function is restored or maintained. Preserved mitochondrial function is clearly associated with better patient outcome. This review elucidates the role of the microcirculation and mitochondria during circulatory shock and patient management and will give a viewpoint on the advantages and disadvantages of tailoring resuscitation to microvascular or mitochondrial targets.
Collapse
Affiliation(s)
- Tamara Merz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Nicole Denoix
- Clinic for Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
| | - Markus Huber-Lang
- Institute for Clinical and Experimental Trauma-Immunology, University Hospital of Ulm, Ulm, Germany
| | - Mervyn Singer
- Bloomsbury Institute for Intensive Care Medicine, University College London, London, United Kingdom
| | - Peter Radermacher
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Oscar McCook
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| |
Collapse
|
10
|
Haeberle H, Prohaska S, Martus P, Straub A, Zarbock A, Marx G, Zago M, Giera M, Koeppen M, Rosenberger P. Therapeutic iloprost for the treatment of acute respiratory distress syndrome (ARDS) (the ThIlo trial): a prospective, randomized, multicenter phase II study. Trials 2020; 21:242. [PMID: 32131881 PMCID: PMC7057516 DOI: 10.1186/s13063-020-4163-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 02/12/2020] [Indexed: 01/08/2023] Open
Abstract
Background Acute respiratory distress syndrome (ARDS) is caused by rapid-onset (within hours) acute inflammatory processes in lung tissue, and it is a life-threatening condition with high mortality. The treatment of ARDS to date is focused on the prevention of further iatrogenic damage of the lung rather than the treatment of the initial inflammatory process. Several preclinical studies have revealed a beneficial effect of iloprost on the control of pulmonary inflammation, and in a small number of patients with ARDS, iloprost treatment resulted in improved oxygenation. Therefore, we plan to conduct a large multicenter trial to evaluate the effect of iloprost on ARDS. Methods The Therapeutic Iloprost during ARDS trial (ThIlo trial) is a multicenter, randomized, single blinded, clinical phase II trial assessing the efficacy of inhaled iloprost for the prevention of the development and progression of ARDS in critically ill patients. One hundred fifty critically ill patients suffering from acute ARDS will be treated either by nebulized iloprost or NaCl 0.9% for 5 days. Blood samples will be drawn at defined time points to elucidate the serum levels of iloprost and inflammatory markers during treatment. Mechanical ventilation will be standardized. In follow-up visits at days 28 and 90 as well as 6 months after enrollment, functional status according to the Barthel Index and a health care-related questionnaire, and frailty (Vulnerable Elders Survey) will be evaluated. The primary endpoint is the improvement of oxygenation, defined as the ratio of PaO2/FiO2. Secondary endpoints include 90-day all-cause mortality, Sequential Organ Failure Assessment scores during the study period up to day 90, the duration of mechanical ventilation, the length of intensive care unit (ICU) stay, ventilator-associated pneumonia, delirium, ICU-acquired weakness, and discharge localization. The study will be conducted in three university ARDS centers in Germany. Discussion The results of the ThIlo trial will highlight the anti-inflammatory effect of iloprost on early inflammatory processes during ARDS, resulting in the improvement of outcome parameters in patients with ARDS. Trial registration EUDRA-CT: 2016-003168-37. Registered on 12 April 2017. ClinicalTrials.gov: NCT03111212. Registered on 4 June 2017.
Collapse
Affiliation(s)
- Helene Haeberle
- Department of Anesthesiology and Intensive Care Medicine, University Hospital, Universitätsklinikum Tübingen, Universitätsklinikum Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany.
| | - Stefanie Prohaska
- Department of Anesthesiology and Intensive Care Medicine, University Hospital, Universitätsklinikum Tübingen, Universitätsklinikum Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany
| | - Peter Martus
- Institute for Clinical Epidemiology und Applied Biostatistics, Eberhard Karls University, Tübingen, Germany
| | - Andreas Straub
- Department of Anesthesiology and Intensive Care Medicine, University Hospital, Universitätsklinikum Tübingen, Universitätsklinikum Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany
| | - Alexander Zarbock
- Department of Anesthesiology, Intensive Care Therapy and Pain Medicine, University Hospital Münster, Münster, Germany
| | - Gernot Marx
- Department of Intensive Care Medicine and Intermediate Care, University Hospital RWTH Aachen, Medical Faculty RWTH Aachen University, Aachen, Germany
| | - Manola Zago
- Center for Clinical Studies, University Hospital, Tübingen, Germany
| | - Martin Giera
- Center for Proteomics and Metabolomics, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Michael Koeppen
- Department of Anesthesiology and Intensive Care Medicine, University Hospital, Universitätsklinikum Tübingen, Universitätsklinikum Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany
| | - Peter Rosenberger
- Department of Anesthesiology and Intensive Care Medicine, University Hospital, Universitätsklinikum Tübingen, Universitätsklinikum Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany.
| |
Collapse
|
11
|
Lankadeva YR, Okazaki N, Evans RG, Bellomo R, May CN. Renal Medullary Hypoxia: A New Therapeutic Target for Septic Acute Kidney Injury? Semin Nephrol 2019; 39:543-553. [DOI: 10.1016/j.semnephrol.2019.10.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
12
|
Legrand M, De Backer D, Dépret F, Ait-Oufella H. Recruiting the microcirculation in septic shock. Ann Intensive Care 2019; 9:102. [PMID: 31512059 PMCID: PMC6738355 DOI: 10.1186/s13613-019-0577-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 09/05/2019] [Indexed: 01/22/2023] Open
Affiliation(s)
- Matthieu Legrand
- Department of Anesthesiology and Perioperative Care, University of California, San Francisco, USA. .,AP-HP, GH Saint Louis-Lariboisière, Department of Anesthesiology and Critical Care and Burn Unit, University Paris Diderot, Paris, France. .,UMR INSERM 942, Institut National de la Santé et de la Recherche Médicale (INSERM), Paris, France. .,F-CRIN, INICRCT Network, Nancy, France.
| | - Daniel De Backer
- Department of Intensive Care, CHIREC Hospitals, Université Libre de Bruxelles, Brussels, Belgium
| | - François Dépret
- AP-HP, GH Saint Louis-Lariboisière, Department of Anesthesiology and Critical Care and Burn Unit, University Paris Diderot, Paris, France.,UMR INSERM 942, Institut National de la Santé et de la Recherche Médicale (INSERM), Paris, France.,F-CRIN, INICRCT Network, Nancy, France
| | - Hafid Ait-Oufella
- Department of Critical Care, AP-HP, Saint Antoine Hospital, Paris, France.,INSERM U970, Paris Cardiovascular Center, Paris, France
| |
Collapse
|
13
|
Cao Y, Guan Y, Xu YY, Hao CM. Endothelial prostacyclin protects the kidney from ischemia-reperfusion injury. Pflugers Arch 2018; 471:543-555. [PMID: 30413885 PMCID: PMC6435627 DOI: 10.1007/s00424-018-2229-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 10/11/2018] [Accepted: 10/23/2018] [Indexed: 01/20/2023]
Abstract
Prostacyclin, or PGI2, is a product of PGI synthase (PGIS), down-stream of cyclooxygenase pathway. PGI2 has been demonstrated to play an important role in maintaining renal blood flow. Non-steroidal anti-inflammatory drugs (NSAIDs) that inhibit cyclooxygenase are reported to increase the susceptibility of patients to acute kidney injury (AKI). This study explores the role of endothelium-derived prostacyclin in ischemia-reperfusion injury (I/RI). The renal PGIS expression and PGI2 production markedly increased following I/RI. Loss of one allele of PGIS gene or selective endothelial PGIS deletion (TEK-CRE PGISfl/fl mice) caused more severe renal damage following I/RI than control mice. Iloprost, a PGI2 analog, administered 30 min before the I/R surgery, markedly attenuated the renal damage in both control mice and TEK-CRE PGISfl/fl mice. Renal p-PKA expression significantly increased after I/RI in wild-type mice but not in the PGIS deletion mice, consistent with IP receptor mediating the protective effect. Further studies showed that PGIS deficiency was associated with reduced fluorescence microsphere accumulation in the kidney following I/R. Folic acid also induced marked kidney injury; however, endothelial PGIS deletion did not worsen kidney injury compared with wild-type mice. These studies indicate that PGIS-derived PGI2 can protect the kidney from acute injury caused by ischemia and reperfusion and PGIS/PGI2 is a potential intervention target for AKI.
Collapse
Affiliation(s)
- Yingxue Cao
- Division of Nephrology, Huashan Hospital, Fudan University, 12 Wulumuqi Road (middle), Shanghai, 200040, China
| | - Yi Guan
- Division of Nephrology, Huashan Hospital, Fudan University, 12 Wulumuqi Road (middle), Shanghai, 200040, China
| | - Yun-Yu Xu
- Division of Nephrology, Huashan Hospital, Fudan University, 12 Wulumuqi Road (middle), Shanghai, 200040, China
| | - Chuan-Ming Hao
- Division of Nephrology, Huashan Hospital, Fudan University, 12 Wulumuqi Road (middle), Shanghai, 200040, China.
| |
Collapse
|
14
|
Meurer M, Ebert K, Schweda F, Höcherl K. The renal vasodilatory effect of prostaglandins is ameliorated in isolated-perfused kidneys of endotoxemic mice. Pflugers Arch 2018; 470:1691-1703. [DOI: 10.1007/s00424-018-2183-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 12/29/2022]
|
15
|
Guerci P, Ergin B, Ince C. The macro- and microcirculation of the kidney. Best Pract Res Clin Anaesthesiol 2017; 31:315-329. [PMID: 29248139 DOI: 10.1016/j.bpa.2017.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/25/2017] [Indexed: 01/22/2023]
Abstract
Acute kidney injury (AKI) remains one of the main causes of morbidity and mortality in the intensive care medicine today. Its pathophysiology and progress to chronic kidney disease is still under investigation. In addition, the lack of techniques to adequately monitor renal function and microcirculation at the bedside makes its therapeutic resolution challenging. In this article, we review current concepts related to renal hemodynamics compromise as being the event underlying AKI. In doing so, we discuss the physiology of the renal circulation and the effects of alterations in systemic hemodynamics that lead to renal injury specifically in the context of reperfusion injury and sepsis. The ultimate key culprit of AKI leading to failure is the dysfunction of the renal microcirculation. The cellular and subcellular components of the renal microcirculation are discussed and how their injury contributes to AKI is described.
Collapse
Affiliation(s)
- Philippe Guerci
- Department of Anesthesiology and Critical Care Medicine, University Hospital of Nancy, France; INSERM U1116, University of Lorraine, Vandoeuvre-Les-Nancy, France; Department of Translational Physiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Bulent Ergin
- Department of Translational Physiology, Academic Medical Centre, Amsterdam, The Netherlands; Department of Intensive Care Medicine, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands
| | - Can Ince
- Department of Translational Physiology, Academic Medical Centre, Amsterdam, The Netherlands; Department of Intensive Care Medicine, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
| |
Collapse
|
16
|
Intravenous iloprost to recruit the microcirculation in septic shock patients? Intensive Care Med 2017; 44:121-122. [PMID: 28921126 DOI: 10.1007/s00134-017-4935-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2017] [Indexed: 10/18/2022]
|
17
|
Zafrani L, Ergin B, Kapucu A, Ince C. Blood transfusion improves renal oxygenation and renal function in sepsis-induced acute kidney injury in rats. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2016; 20:406. [PMID: 27993148 PMCID: PMC5168817 DOI: 10.1186/s13054-016-1581-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Accepted: 11/25/2016] [Indexed: 11/29/2022]
Abstract
Background The effects of blood transfusion on renal microcirculation during sepsis are unknown. This study aimed to investigate the effect of blood transfusion on renal microvascular oxygenation and renal function during sepsis-induced acute kidney injury. Methods Twenty-seven Wistar albino rats were randomized into four groups: a sham group (n = 6), a lipopolysaccharide (LPS) group (n = 7), a LPS group that received fluid resuscitation (n = 7), and a LPS group that received blood transfusion (n = 7). The mean arterial blood pressure, renal blood flow, and renal microvascular oxygenation within the kidney cortex were recorded. Acute kidney injury was assessed using the serum creatinine levels, metabolic cost, and histopathological lesions. Nitrosative stress (expression of endothelial (eNOS) and inducible nitric oxide synthase (iNOS)) within the kidney was assessed by immunohistochemistry. Hemoglobin levels, pH, serum lactate levels, and liver enzymes were measured. Results Fluid resuscitation and blood transfusion both significantly improved the mean arterial pressure and renal blood flow after LPS infusion. Renal microvascular oxygenation, serum creatinine levels, and tubular damage significantly improved in the LPS group that received blood transfusion compared to the group that received fluids. Moreover, the renal expression of eNOS was markedly suppressed under endotoxin challenge. Blood transfusion, but not fluid resuscitation, was able to restore the renal expression of eNOS. However, there were no significant differences in lactic acidosis or liver function between the two groups. Conclusions Blood transfusion significantly improved renal function in endotoxemic rats. The specific beneficial effect of blood transfusion on the kidney could have been mediated in part by the improvements in renal microvascular oxygenation and sepsis-induced endothelial dysfunction via the restoration of eNOS expression within the kidney. Electronic supplementary material The online version of this article (doi:10.1186/s13054-016-1581-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Lara Zafrani
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Bulent Ergin
- Department of Intensive Care, Erasmus MC, University of Medical Center, Rotterdam, The Netherlands
| | - Aysegul Kapucu
- Department of Biology, Faculty of Science, University of Istanbul, Istanbul, Turkey
| | - Can Ince
- Department of Intensive Care, Erasmus MC, University of Medical Center, Rotterdam, The Netherlands.
| |
Collapse
|
18
|
Uyar ME, Yucel P, Ilin S, Bal Z, Yildirim S, Uyar AS, Akay T, Tutal E, Sezer S. Iloprost as an acute kidney injury-triggering agent in severely atherosclerotic patients. Cardiovasc J Afr 2016; 27:128-133. [PMID: 27841898 PMCID: PMC5101430 DOI: 10.5830/cvja-2015-051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 06/14/2015] [Indexed: 01/11/2023] Open
Abstract
Background Iloprost, a stable prostacyclin analog, is used as a rescue therapy for severe peripheral arterial disease (PAD). It has systemic vasodilatory and anti-aggregant effects, with severe vasodilatation potentially causing organ ischaemia when severe atherosclerosis is the underlying cause. In this study, we retrospectively analysed renal outcomes after iloprost infusion therapy in 86 patients. Methods Eighty-six patients with PAD who received iloprost infusion therapy were retrospectively analysed. Clinical and biochemical parameters were recorded before (initial, Cr1), during (third day, Cr2), and after (14th day following the termination of infusion therapy, Cr3) treatment. Acute kidney injury (AKI) was defined according to KDIGO guidelines as a ≥ 0.3 mg/dl (26.52 μmol/l) increase in creatinine levels from baseline within 48 hours. Results: Cr2 (1.46 ± 0.1 mg/dl) (129.06 ± 8.84 μmol/l) and Cr3 (1.53 ± 0.12 mg/dl) (135.25 ± 10.61 μmol/l) creatinine levels were significantly higher compared to the initial value (1.15 ± 0.6 mg/dl) (101.66 ± 53.04 μmol/l). AKI was observed in 36 patients (41.86%) on the third day of iloprost infusion. Logistic regression analysis revealed smoking and not using acetylsalicylic acid as primary predictors (p = 0.02 and p = 0.008, respectively) of AKI during iloprost treatment. On the third infusion day, patients’ urinary output significantly increased (1813.30 ± 1123.46 vs 1545.17 ± 873.00 cm3) and diastolic blood pressure significantly decreased (70.07 ± 15.50 vs 74.14 ± 9.42 mmHg) from their initial values. Conclusion While iloprost treatment is effective in patients with PAD who are not suitable for surgery, severe systemic vasodilatation can cause renal ischaemia, resulting in nonoliguric AKI. Smoking, no acetylsalicylic acid use, and lower diastolic blood pressure are the clinical risk factors for AKI during iloprost treatment.
Collapse
Affiliation(s)
| | - Piril Yucel
- Department of Internal Medicine, Baskent University, Ankara, Turkey
| | - Sena Ilin
- Department of Internal Medicine, Baskent University, Ankara, Turkey
| | - Zeynep Bal
- Department of Internal Medicine, Baskent University, Ankara, Turkey
| | - Saliha Yildirim
- Department of Internal Medicine, Baskent University, Ankara, Turkey
| | - Ahmet Senol Uyar
- Department of Anesthesiology, Ulucanlar Eye Education and Research Hospital, Ankara, Turkey
| | - Tankut Akay
- Department of Cardiovascular Surgery, Baskent University, Ankara, Turkey
| | - Emre Tutal
- Department of Nephrology, Baskent University, Ankara, Turkey
| | - Siren Sezer
- Department of Nephrology, Baskent University, Ankara, Turkey
| |
Collapse
|
19
|
Post EH, Kellum JA, Bellomo R, Vincent JL. Renal perfusion in sepsis: from macro- to microcirculation. Kidney Int 2016; 91:45-60. [PMID: 27692561 DOI: 10.1016/j.kint.2016.07.032] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/01/2016] [Accepted: 07/07/2016] [Indexed: 12/16/2022]
Abstract
The pathogenesis of sepsis-associated acute kidney injury is complex and likely involves perfusion alterations, a dysregulated inflammatory response, and bioenergetic derangements. Although global renal hypoperfusion has been the main target of therapeutic interventions, its role in the development of renal dysfunction in sepsis is controversial. The implications of renal hypoperfusion during sepsis probably extend beyond a simple decrease in glomerular filtration pressure, and targeting microvascular perfusion deficits to maintain tubular epithelial integrity and function may be equally important. In this review, we provide an overview of macro- and microcirculatory dysfunction in experimental and clinical sepsis and discuss relationships with kidney oxygenation, metabolism, inflammation, and function.
Collapse
Affiliation(s)
- Emiel Hendrik Post
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - John A Kellum
- Center for Critical Care Nephrology, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Rinaldo Bellomo
- Centre for Integrated Critical Care, School of Medicine, The University of Melbourne, Parkville, Melbourne, Australia
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium.
| |
Collapse
|
20
|
Effects of N-acetylcysteine (NAC) supplementation in resuscitation fluids on renal microcirculatory oxygenation, inflammation, and function in a rat model of endotoxemia. Intensive Care Med Exp 2016; 4:29. [PMID: 27671340 PMCID: PMC5037099 DOI: 10.1186/s40635-016-0106-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 09/20/2016] [Indexed: 12/18/2022] Open
Abstract
Background Modulation of inflammation and oxidative stress appears to limit sepsis-induced damage in experimental models. The kidney is one of the most sensitive organs to injury during septic shock. In this study, we evaluated the effect of N-acetylcysteine (NAC) administration in conjunction with fluid resuscitation on renal oxygenation and function. We hypothesized that reducing inflammation would improve the microcirculatory oxygenation in the kidney and limit the onset of acute kidney injury (AKI). Methods Rats were randomized into five groups (n = 8 per group): (1) control group, (2) control + NAC, (3) endotoxemic shock with lipopolysaccharide (LPS) without fluids, (4) LPS + fluid resuscitation, and (5) LPS + fluid resuscitation + NAC (150 mg/kg/h). Fluid resuscitation was initiated at 120 min and maintained at fixed volume for 2 h with hydroxyethyl starch (HES 130/0.4) dissolved in acetate-balanced Ringer’s solution (Volulyte) with or without supplementation with NAC (150 mg/kg/h). Oxygen tension in the renal cortex (CμPO2), outer medulla (MμPO2), and renal vein was measured using phosphorimetry. Biomarkers of renal injury, inflammation, and oxidative stress were assessed in kidney tissues. Results Fluid resuscitation significantly improved the systemic and renal macrohemodynamic parameters after LPS. However, the addition of NAC further improved cortical renal oxygenation, oxygen delivery, and oxygen consumption (p < 0.05). NAC supplementation dampened the accumulation of NGAL or L-FABP, hyaluronic acid, and nitric oxide in kidney tissue (p < 0.01). Conclusion The addition of NAC to fluid resuscitation may improve renal oxygenation and attenuate microvascular dysfunction and AKI. Decreases in renal NO and hyaluronic acid levels may be involved in this beneficial effect. A therapeutic strategy combining initial fluid resuscitation with antioxidant therapies may prevent sepsis-induced AKI.
Collapse
|
21
|
The Complex Relationship of Extracorporeal Membrane Oxygenation and Acute Kidney Injury: Causation or Association? BIOMED RESEARCH INTERNATIONAL 2016; 2016:1094296. [PMID: 27006941 PMCID: PMC4783537 DOI: 10.1155/2016/1094296] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 01/29/2016] [Accepted: 01/31/2016] [Indexed: 12/23/2022]
Abstract
Extracorporeal membrane oxygenation (ECMO) is a modified cardiopulmonary bypass (CPB) circuit capable of providing prolonged cardiorespiratory support. Recent advancement in ECMO technology has resulted in increased utilisation and clinical application. It can be used as a bridge-to-recovery, bridge-to-bridge, bridge-to-transplant, or bridge-to-decision. ECMO can restitute physiology in critically ill patients, which may minimise the risk of progressive multiorgan dysfunction. Alternatively, iatrogenic complications of ECMO clearly contribute to worse outcomes. These factors affect the risk : benefit ratio of ECMO which ultimately influence commencement/timing of ECMO. The complex interplay of pre-ECMO, ECMO, and post-ECMO pathophysiological processes are responsible for the substantial increased incidence of ECMO-associated acute kidney injury (EAKI). The development of EAKI significantly contributes to morbidity and mortality; however, there is a lack of evidence defining a potential benefit or causative link between ECMO and AKI. This area warrants investigation as further research will delineate the mechanisms involved and subsequent strategies to minimise the risk of EAKI. This review summarizes the current literature of ECMO and AKI, considers the possible benefits and risks of ECMO on renal function, outlines the related pathophysiology, highlights relevant investigative tools, and ultimately suggests an approach for future research into this under investigated area of critical care.
Collapse
|
22
|
Zafrani L, Ince C. Microcirculation in Acute and Chronic Kidney Diseases. Am J Kidney Dis 2015; 66:1083-94. [DOI: 10.1053/j.ajkd.2015.06.019] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 06/15/2015] [Indexed: 01/20/2023]
|
23
|
Rodríguez-Romo R, Berman N, Gómez A, Bobadilla NA. Epigenetic regulation in the acute kidney injury to chronic kidney disease transition. Nephrology (Carlton) 2015; 20:736-743. [DOI: 10.1111/nep.12521] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2015] [Indexed: 02/06/2023]
Affiliation(s)
- Roxana Rodríguez-Romo
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| | - Nathan Berman
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| | - Arturo Gómez
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| | - Norma A Bobadilla
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| |
Collapse
|
24
|
Antithrombin III/SerpinC1 insufficiency exacerbates renal ischemia/reperfusion injury. Kidney Int 2015; 88:796-803. [PMID: 26108065 PMCID: PMC4589441 DOI: 10.1038/ki.2015.176] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 04/09/2015] [Accepted: 04/16/2015] [Indexed: 12/23/2022]
Abstract
Antithrombin III, encoded by SerpinC1, is a major anti-coagulation molecule in vivo and has anti-inflammatory effects. We found that patients with low antithrombin III activities presented a higher risk of developing acute kidney injury after cardiac surgery. To study this further, we generated SerpinC1 heterozygous knockout rats and followed the development of acute kidney injury in a model of modest renal ischemia/reperfusion injury. Renal injury, assessed by serum creatinine and renal tubular injury scores after 24 h of reperfusion, was significantly exacerbated in SerpinC1(+/-) rats compared to wild-type littermates. Concomitantly, renal oxidative stress, tubular apoptosis, and macrophage infiltration following this injury were significantly aggravated in SerpinC1(+/-) rats. However, significant thrombosis was not found in the kidneys of any group of rats. Antithrombin III is reported to stimulate the production of prostaglandin I2, a known regulator of renal cortical blood flow, in addition to having anti-inflammatory effects and to protect against renal failure. Prostaglandin F1α, an assayable metabolite of prostaglandin I2, was increased in the kidneys of the wild-type rats at 3 h after reperfusion. The increase of prostaglandin F1α was significantly blunted in SerpinC1(+/-) rats, which preceded increased tubular injury and oxidative stress. Thus, our study found a novel role of SerpinC1 insufficiency in increasing the severity of renal ischemia/reperfusion injury.
Collapse
|
25
|
|
26
|
Ince C. The central role of renal microcirculatory dysfunction in the pathogenesis of acute kidney injury. Nephron Clin Pract 2014; 127:124-8. [PMID: 25343835 DOI: 10.1159/000363203] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Acute kidney injury (AKI) is a rapidly developing condition often associated with critical illness, with a high degree of morbidity and mortality, whose pathophysiology is ill understood. Recent investigations have identified the dysfunction of the renal microcirculation and its cellular and subcellular constituents as being central to the etiology of AKI. Injury is caused by inflammatory activation involving endothelial leucocyte interactions in combination with dysregulation of the homeostatis between oxygen, nitric oxide, and reactive oxygen species. Effective therapies expected to resolve AKI will have to control inflammation and restore this homeostasis. In order to apply and guide these therapies effectively, diagnostic tools aimed at physiological biomarkers of AKI for monitoring renal microcirculatory function in advance of changes in pharmacological biomarkers associated with structural damage of the kidney will need to be developed.
Collapse
Affiliation(s)
- Can Ince
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| |
Collapse
|
27
|
Ergin B, Kapucu A, Demirci-Tansel C, Ince C. The renal microcirculation in sepsis. Nephrol Dial Transplant 2014; 30:169-77. [PMID: 24848133 DOI: 10.1093/ndt/gfu105] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Despite identification of several cellular mechanisms being thought to underlie the development of septic acute kidney injury (AKI), the pathophysiology of the occurrence of AKI is still poorly understood. It is clear, however, that instead of a single mechanism being responsible for its aetiology, an orchestra of cellular mechanisms failing is associated with AKI. The integrative physiological compartment where these mechanisms come together and exert their integrative deleterious action is the renal microcirculation (MC). This is why it is opportune to review the response of the renal MC to sepsis and discuss the determinants of its (dys)function and how it contributes to the pathogenesis of renal failure. A main determinant of adequate organ function is the adequate supply and utilization of oxygen at the microcirculatory and cellular level to perform organ function. The highly complex architecture of the renal microvasculature, the need to meet a high energy demand and the fact that the kidney is borderline ischaemic makes the kidney a highly vulnerable organ to hypoxaemic injury. Under normal, steady-state conditions, oxygen (O2) supply to the renal tissues is well regulated; however, under septic conditions the delicate balance of oxygen supply versus demand is disturbed due to renal microvasculature dysfunction. This dysfunction is largely due to the interaction of renal oxygen handling, nitric oxide metabolism and radical formation. Renal tissue oxygenation is highly heterogeneous not only between the cortex and medulla but also within these renal compartments. Integrative evaluation of the different determinants of tissue oxygen in sepsis models has identified the deterioration of microcirculatory oxygenation as a key component in the development AKI. It is becoming clear that resuscitation of the failing kidney needs to integratively correct the homeostasis between oxygen, and reactive oxygen and nitrogen species. Several experimental therapeutic modalities have been found to be effective in restoring microcirculatory oxygenation in parallel to improving renal function following septic AKI. However, these have to be verified in clinical studies. The development of clinical physiological biomarkers of AKI specifically aimed at the MC should form a valuable contribution to monitoring such new therapeutic modalities.
Collapse
Affiliation(s)
- Bulent Ergin
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Aysegul Kapucu
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands Department of Biology and Zoology Division, University of Istanbul, Istanbul, Turkey
| | - Cihan Demirci-Tansel
- Department of Biology and Zoology Division, University of Istanbul, Istanbul, Turkey
| | - Can Ince
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| |
Collapse
|
28
|
Ay Y, Kara I, Ay NK, Aydin C, Koksal C, Gorur DA, Findik O. The effect of iloprost on renal function in patients with critical limb ischemia. Curr Ther Res Clin Exp 2014; 75:33-8. [PMID: 24465040 PMCID: PMC3898192 DOI: 10.1016/j.curtheres.2013.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Iloprost, which has efficacy in the microvascular space, is shown to have beneficial effects on the kidney, which has an extensive microvascular network. OBJECTIVE We aimed to evaluate the effect of iloprost treatment on kidney functions in patients with critical limb ischemia. METHODS Forty-eight patients with critical limb ischemia who were not suitable for revascularization and who were treated with iloprost were evaluated prospectively in our clinic between September 2010 and December 2012. The patients were divided into 2 groups as patients with chronic renal dysfunction (Group I) and patients with normal renal function (Group II). Urine albumin:creatinine ratio and glomerular filtration rate (GFR) calculated using serum creatinine and serum cystatin C (GFRcyc) were used to establish the presence of renal dysfunction. The decrease analgesic requirement, walking distance, reduction in ulcer diameter, the increase in ankle-brachial index, and changes in The Society of Vascular Surgery/International Society of Cardiovascular Surgery criteria were used in the evaluation of treatment response. RESULTS Opioid analgesic requirement and decubitus pain disappeared after treatment in 58.3% (n = 28) of subjects. Walking distance increased in 66.6% (n = 32). Iloprost treatment significantly increased ankle-brachial index (P < 0.01). In Group I the levels of serum urea, creatinine, and cystatin C significantly decreased (P < 0.05), whereas GFRcyc and GFR calculated using the equation of the Chronic Kidney Disease Epidemiology Collaboration (ie, GFR expressed for specified race, sex, and serum creatinine in milligrams per deciliter) was increased significantly compared with pretreatment levels (P < 0.05). No significant change was observed in urine albumin:creatinine ratio (P > 0.05). CONCLUSIONS The use of iloprost in critical limb ischemia can slow down the progress of early stage renal damage. GFRcyc and cystatin C, which are indicators of early stage chronic renal dysfunction, can be used for the evaluation of treatment response.
Collapse
Affiliation(s)
- Yasin Ay
- Department of Cardiovascular Surgery, Bezmialem Vakif University, Fatih, Istanbul, Turkey
- Address correspondence to: Yasin Ay, MD, Department of Cardiovascular Surgery, Bezmialem Vakif University, Adnan Menderes Bulvarı (Vatan Cad), 34093, Fatih, Istanbul, Turkey.
| | - Ibrahim Kara
- Department of Cardiovascular Surgery, Sakarya University School of Medicine, Sakarya, Turkey
| | - Nuray Kahraman Ay
- Department of Cardiovascular Surgery, Bezmialem Vakif University, Fatih, Istanbul, Turkey
| | - Cemalettin Aydin
- Department of Cardiovascular Surgery, Bezmialem Vakif University, Fatih, Istanbul, Turkey
| | - Cengiz Koksal
- Department of Cardiovascular Surgery, Kartal Kosuyolu Training and Research Hospital, Kartal, Istanbul, Turkey
| | - Durmus Alper Gorur
- Department of Cardiovascular Surgery, Derince Training and Research Hospital, Derince, Kocaeli, Turkey
| | - Orhan Findik
- Department of Cardiovascular Surgery, Derince Training and Research Hospital, Derince, Kocaeli, Turkey
| |
Collapse
|
29
|
|
30
|
Cutaneous respirometry by dynamic measurement of mitochondrial oxygen tension for monitoring mitochondrial function in vivo. Mitochondrion 2013; 13:507-14. [DOI: 10.1016/j.mito.2012.10.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 09/19/2012] [Accepted: 10/02/2012] [Indexed: 11/23/2022]
|
31
|
Abstract
Acute kidney injury (AKI) is the leading cause of nephrology consultation and is associated with high mortality rates. The primary causes of AKI include ischemia, hypoxia, or nephrotoxicity. An underlying feature is a rapid decline in glomerular filtration rate (GFR) usually associated with decreases in renal blood flow. Inflammation represents an important additional component of AKI leading to the extension phase of injury, which may be associated with insensitivity to vasodilator therapy. It is suggested that targeting the extension phase represents an area potential of treatment with the greatest possible impact. The underlying basis of renal injury appears to be impaired energetics of the highly metabolically active nephron segments (i.e., proximal tubules and thick ascending limb) in the renal outer medulla, which can trigger conversion from transient hypoxia to intrinsic renal failure. Injury to kidney cells can be lethal or sublethal. Sublethal injury represents an important component in AKI, as it may profoundly influence GFR and renal blood flow. The nature of the recovery response is mediated by the degree to which sublethal cells can restore normal function and promote regeneration. The successful recovery from AKI depends on the degree to which these repair processes ensue and these may be compromised in elderly or chronic kidney disease (CKD) patients. Recent data suggest that AKI represents a potential link to CKD in surviving patients. Finally, earlier diagnosis of AKI represents an important area in treating patients with AKI that has spawned increased awareness of the potential that biomarkers of AKI may play in the future.
Collapse
Affiliation(s)
- David P Basile
- Department of Cellular & Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA.
| | | | | |
Collapse
|
32
|
Bodmer SIA, Balestra GM, Harms FA, Johannes T, Raat NJH, Stolker RJ, Mik EG. Microvascular and mitochondrial PO(2) simultaneously measured by oxygen-dependent delayed luminescence. JOURNAL OF BIOPHOTONICS 2012; 5:140-151. [PMID: 22114031 DOI: 10.1002/jbio.201100082] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 11/03/2011] [Accepted: 11/03/2011] [Indexed: 05/31/2023]
Abstract
Measurement of tissue oxygenation is a complex task and various techniques have led to a wide range of tissue PO(2) values and contradictory results. Tissue is compartmentalized in microcirculation, interstitium and intracellular space and current techniques are biased towards a certain compartment. Simultaneous oxygen measurements in various compartments might be of great benefit for our understanding of determinants of tissue oxygenation. Here we report simultaneous measurement of microvascular PO(2) (μPO(2) ) and mitochondrial PO(2) (mitoPO(2) ) in rats. The μPO(2) measurements are based on oxygen-dependent quenching of phosphorescence of the near-infrared phosphor Oxyphor G2. The mitoPO(2) measurements are based on oxygen-dependent quenching of delayed fluorescence of protoporphyrin IX (PpIX). Favorable spectral properties of these porphyrins allow simultaneous measurement of the delayed luminescence lifetimes. A dedicated fiber-based time-domain setup consisting of a tunable pulsed laser, 2 red-sensitive gated photomultiplier tubes and a simultaneous sampling data-acquisition system is described in detail. The absence of cross talk between the channels is shown and the feasibility of simultaneous μPO(2) and mitoPO(2) measurements is demonstrated in rat liver in vivo. It is anticipated that this novel approach will greatly contribute to our understanding of tissue oxygenation in physiological and pathological circumstances.
Collapse
Affiliation(s)
- Sander I A Bodmer
- Department of Anesthesiology, Laboratory of Experimental Anesthesiology, Erasmus MC - University Medical Center Rotterdam, s-Gravendijkwal 230, 3015 CE, Rotterdam, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
33
|
|
34
|
Harms FA, de Boon WMI, Balestra GM, Bodmer SIA, Johannes T, Stolker RJ, Mik EG. Oxygen-dependent delayed fluorescence measured in skin after topical application of 5-aminolevulinic acid. JOURNAL OF BIOPHOTONICS 2011; 4:731-739. [PMID: 21770036 DOI: 10.1002/jbio.201100040] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 06/26/2011] [Accepted: 06/27/2011] [Indexed: 05/31/2023]
Abstract
Mitochondrial oxygen tension can be measured in vivo by means of oxygen-dependent quenching of delayed fluorescence of protoporphyrin IX (PpIX). Here we demonstrate that delayed fluorescence is readily observed from skin in rat and man after topical application of the PpIX precursor 5-aminolevulinic acid (ALA). Delayed fluorescence lifetimes respond to changes in inspired oxygen fraction and blood supply. The signals contain lifetime distributions and the fitting of rectangular distributions to the data appears more adequate than mono-exponential fitting. The use of topically applied ALA for delayed fluorescence lifetime measurements might pave the way for clinical use of this technique.
Collapse
Affiliation(s)
- Floor A Harms
- Department of Anesthesiology, Laboratory of Experimental Anesthesiology, ErasmusMC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
35
|
Badin J, Boulain T, Ehrmann S, Skarzynski M, Bretagnol A, Buret J, Benzekri-Lefevre D, Mercier E, Runge I, Garot D, Mathonnet A, Dequin PF, Perrotin D. Relation between mean arterial pressure and renal function in the early phase of shock: a prospective, explorative cohort study. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2011; 15:R135. [PMID: 21645384 PMCID: PMC3219004 DOI: 10.1186/cc10253] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/30/2011] [Accepted: 06/06/2011] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Because of disturbed renal autoregulation, patients experiencing hypotension-induced renal insult might need higher levels of mean arterial pressure (MAP) than the 65 mmHg recommended level in order to avoid the progression of acute kidney insufficiency (AKI). METHODS In 217 patients with sustained hypotension, enrolled and followed prospectively, we compared the evolution of the mean arterial pressure (MAP) during the first 24 hours between patients who will show AKI 72 hours after inclusion (AKIh72) and patients who will not. AKIh72 was defined as the need of renal replacement therapy or "Injury" or "Failure" classes of the 5-stage RIFLE classification (Risk, Injury, Failure, Loss of kidney function, End-stage renal disease) for acute kidney insufficiency using the creatinine and urine output criteria. This comparison was performed in four different subgroups of patients according to the presence or not of AKI at the sixth hour after inclusion (AKIh6 as defined as a serum creatinine level above 1.5 times baseline value within the first six hours) and the presence or not of septic shock at inclusion.The ability of MAP averaged over H6 to H24 to predict AKIh72 was assessed by the area under the receiver operating characteristic curve (AUC) and compared between groups. RESULTS The MAP averaged over H6 to H24 or over H12 to H24 was significantly lower in patients who showed AKIh72 than in those who did not, only in septic shock patients with AKIh6, whereas no link was found between MAP and AKIh72 in the three others subgroups of patients. In patients with septic shock plus AKIh6, MAP averaged over H6 to H24 or over H12 to H24 had an AUC of 0.83 (0.72 to 0.92) or 0.84 (0.72 to 0.92), respectively, to predict AKIh72 . In these patients, the best level of MAP to prevent AKIh72 was between 72 and 82 mmHg. CONCLUSIONS MAP about 72 to 82 mmHg could be necessary to avoid acute kidney insufficiency in patients with septic shock and initial renal function impairment.
Collapse
Affiliation(s)
- Julie Badin
- Service de Réanimation Médicale, Hôpital La Source, Centre Hospitalier Régional, avenue de l'Hôpital, Orléans Cedex 1, France
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Bezemer R, Faber DJ, Almac E, Kalkman J, Legrand M, Heger M, Ince C. Evaluation of multi-exponential curve fitting analysis of oxygen-quenched phosphorescence decay traces for recovering microvascular oxygen tension histograms. Med Biol Eng Comput 2010; 48:1233-42. [PMID: 21046272 PMCID: PMC2993890 DOI: 10.1007/s11517-010-0698-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Accepted: 10/08/2010] [Indexed: 11/29/2022]
Abstract
Although it is generally accepted that oxygen-quenched phosphorescence decay traces can be analyzed using the exponential series method (ESM), its application until now has been limited to a few (patho)physiological studies, probably because the reliability of the recovered oxygen tension (pO(2)) histograms has never been extensively evaluated and lacks documentation. The aim of this study was, therefore, to evaluate the use of the ESM to adequately determine pO(2) histograms from phosphorescence decay traces. For this purpose we simulated decay traces corresponding to uni- and bimodal pO(2) distributions and recovered the pO(2) histograms at different signal-to-noise ratios (SNRs). Ultimately, we recovered microvascular pO(2) histograms measured in the rat kidney in a model of endotoxemic shock and fluid resuscitation and showed that the mean microvascular oxygen tension, [Symbol: see text]pO(2)[Symbol: see text], decreased after induction of endotoxemia and that after 2 h of fluid resuscitation, [Symbol: see text]pO(2)[Symbol: see text] remained low, but the hypoxic peak that had arisen during endotoxemia was reduced. This finding illustrates the importance of recovering pO(2) histograms under (patho)physiological conditions. In conclusion, this study has characterized how noise affects the recovery of pO(2) histograms using the ESM and documented the reliability of the ESM for recovering both low- and high-pO(2) distributions for SNRs typically found in experiments. This study might therefore serve as a frame of reference for investigations focused on oxygen (re)distribution during health and disease and encourage researchers to (re-)analyze data obtained in (earlier) studies possibly revealing new insights into complex disease states and treatment strategies.
Collapse
Affiliation(s)
- Rick Bezemer
- Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|
37
|
Mediators of inflammation in acute kidney injury. Mediators Inflamm 2010; 2009:137072. [PMID: 20182538 PMCID: PMC2825552 DOI: 10.1155/2009/137072] [Citation(s) in RCA: 337] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 11/18/2009] [Indexed: 12/13/2022] Open
Abstract
Acute kidney injury (AKI) remains to be an independent risk factor for mortality and morbidity. Inflammation is now believed to play a major role in the pathopathophysiology of AKI. It is hypothesized that in ischemia, sepsis and nephrotoxic models that the initial insult results in morphological and/or functional changes in vascular endothelial cells and/or in tubular epithelium. Then, leukocytes including neutrophils, macrophages, natural killer cells, and lymphocytes infiltrate into the injured kidneys. The injury induces the generation of inflammatory mediators like cytokines and chemokines by tubular and endothelial cells which contribute to the recruiting of leukocytes into the kidneys. Thus, inflammation has an important role in the initiation and extension phases of AKI. This review will focus on the mediators of inflammation contributing to the pathogenesis of AKI.
Collapse
|
38
|
Abstract
PURPOSE OF REVIEW Alterations of the renal microcirculation can promote the development of acute kidney injury through the interlinked occurrence of renal hypoxia and activation of inflammatory pathways. This review focuses on the recent advances in this area, and discusses the possible therapeutic interventions that might be derived from these insights. RECENT FINDINGS Endothelial injury acts as a primary event leading to renal hypoxia with disturbances in nitric oxide pathways playing a major role. The unbalanced homeostasis between nitric oxide, reactive oxygen species and renal oxygenation forms a major component of the microcirculatory dysfunction. Furthermore, injury leads to leukocyte-endothelial interaction that exacerbates renal hypoxia at a microcirculatory level. SUMMARY Knowledge of the pathophysiological mechanisms of acute kidney injury emphasizes the importance of the role of the microcirculation in its development. Preventive and therapeutic approach should be based on restoring the homeostasis between nitric oxide, reactive oxygen species and renal oxygenation.
Collapse
|
39
|
Evans RG, May CN. TISSUE HYPOXIA AS A THERAPEUTIC TARGET IN ACUTE KIDNEY INJURY. Clin Exp Pharmacol Physiol 2009; 36:867-9. [DOI: 10.1111/j.1440-1681.2009.05217.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|