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Hassan S, Wang T, Shi K, Huang Y, Urbina Lopez ME, Gan K, Chen M, Willemen N, Kalam H, Luna-Ceron E, Cecen B, Elbait GD, Li J, Garcia-Rivera LE, Gurian M, Banday MM, Yang K, Lee MC, Zhuang W, Johnbosco C, Jeon O, Alsberg E, Leijten J, Shin SR. Self-oxygenation of engineered living tissues orchestrates osteogenic commitment of mesenchymal stem cells. Biomaterials 2023; 300:122179. [PMID: 37315386 PMCID: PMC10330822 DOI: 10.1016/j.biomaterials.2023.122179] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 04/12/2023] [Accepted: 05/25/2023] [Indexed: 06/16/2023]
Abstract
Oxygenating biomaterials can alleviate anoxic stress, stimulate vascularization, and improve engraftment of cellularized implants. However, the effects of oxygen-generating materials on tissue formation have remained largely unknown. Here, we investigate the impact of calcium peroxide (CPO)-based oxygen-generating microparticles (OMPs) on the osteogenic fate of human mesenchymal stem cells (hMSCs) under a severely oxygen deficient microenvironment. To this end, CPO is microencapsulated in polycaprolactone to generate OMPs with prolonged oxygen release. Gelatin methacryloyl (GelMA) hydrogels containing osteogenesis-inducing silicate nanoparticles (SNP hydrogels), OMPs (OMP hydrogels), or both SNP and OMP (SNP/OMP hydrogels) are engineered to comparatively study their effect on the osteogenic fate of hMSCs. OMP hydrogels associate with improved osteogenic differentiation under both normoxic and anoxic conditions. Bulk mRNAseq analyses suggest that OMP hydrogels under anoxia regulate osteogenic differentiation pathways more strongly than SNP/OMP or SNP hydrogels under either anoxia or normoxia. Subcutaneous implantations reveal a stronger host cell invasion in SNP hydrogels, resulting in increased vasculogenesis. Furthermore, time-dependent expression of different osteogenic factors reveals progressive differentiation of hMSCs in OMP, SNP, and SNP/OMP hydrogels. Our work demonstrates that endowing hydrogels with OMPs can induce, improve, and steer the formation of functional engineered living tissues, which holds potential for numerous biomedical applications, including tissue regeneration and organ replacement therapy.
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Affiliation(s)
- Shabir Hassan
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA; Department of Biology, College of Arts and Sciences, Khalifa University (Main Campus), Abu Dhabi, P.O. Box, 127788, United Arab Emirates; Advanced Materials Chemistry Center (AMCC), Khalifa University (SAN Campus), Abu Dhabi, P.O. Box, 127788, United Arab Emirates
| | - Ting Wang
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA; Department of Laboratory Medicine, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, 210029, China
| | - Kun Shi
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA; Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yike Huang
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Maria Elizabeth Urbina Lopez
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Kaifeng Gan
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Mo Chen
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Niels Willemen
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA; Leijten Lab, Department of Developmental Bioengineering, Faculty of Science and Technology, TechMed Centre, University Twente, Enschede, 7522 NB, the Netherlands
| | - Haroon Kalam
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02139, USA
| | - Eder Luna-Ceron
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Berivan Cecen
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Gihan Daw Elbait
- Department of Biology, College of Arts and Sciences, Khalifa University (Main Campus), Abu Dhabi, P.O. Box, 127788, United Arab Emirates
| | - Jinghang Li
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Luis Enrique Garcia-Rivera
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Melvin Gurian
- Leijten Lab, Department of Developmental Bioengineering, Faculty of Science and Technology, TechMed Centre, University Twente, Enschede, 7522 NB, the Netherlands
| | - Mudassir Meraj Banday
- Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Kisuk Yang
- Center for Nanomedicine, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Boston, MA, 02115, USA; Division of Bioengineering, College of Life Sciences and Bioengineering, Incheon National University, Incheon, 22012, Republic of Korea
| | - Myung Chul Lee
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Weida Zhuang
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA
| | - Castro Johnbosco
- Leijten Lab, Department of Developmental Bioengineering, Faculty of Science and Technology, TechMed Centre, University Twente, Enschede, 7522 NB, the Netherlands
| | - Oju Jeon
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL, 60612, USA
| | - Eben Alsberg
- Department of Biomedical Engineering, University of Illinois Chicago, Chicago, IL, 60612, USA; Departments of Orthopaedic Surgery, Pharmacology and Regenerative Medicine, and Mechanical and Industrial Engineering, University of Illinois Chicago, Chicago, IL, 60612, USA
| | - Jeroen Leijten
- Leijten Lab, Department of Developmental Bioengineering, Faculty of Science and Technology, TechMed Centre, University Twente, Enschede, 7522 NB, the Netherlands.
| | - Su Ryon Shin
- Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, and Brigham and Women's Hospital, Cambridge, MA, 02139, USA.
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Wu Y, Zhou S, Li Y, Huang P, Zhong Z, Dong H, Tian H, Jiang S, Xie J, Li P. Remote ischemic preconditioning improves spatial memory and sleep of young males during acute high-altitude exposure. Travel Med Infect Dis 2023; 53:102576. [PMID: 37068619 DOI: 10.1016/j.tmaid.2023.102576] [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: 01/20/2023] [Revised: 03/28/2023] [Accepted: 04/14/2023] [Indexed: 04/19/2023]
Abstract
OBJECTIVE The high-altitude hypoxia environment will cause poor acclimatization in a portion of the population. Remote ischemic preconditioning(RIPC)has been demonstrated to prevent cardiovascular and cerebrovascular diseases under ischemic or hypoxic conditions. However, its role in improving acclimatization and preventing acute mountain sickness (AMS) at high altitude has been undetermined. This study aims to estimate the effect of RIPC on acclimatization of individuals exposed to high altitude. METHODS The project was designed as a randomized controlled trial with 82 healthy young males, who received RIPC training once a day for 7 consecutive days. Then they were transported by aircraft to a high altitude (3680 m) and examined for 6 days. Lake Louise Score(LLS) of AMS, physiological index, self-reported sleep pattern, and Pittsburgh Sleep Quality Index(PSQI)score were applied to assess the acclimatization to the high altitude. Five neurobehavioral tests were conducted to assess cognitive function. RESULTS The result showed that the RIPC group had a significantly lower AMSscore than the control group (2.43 ± 1.58 vs 3.29 ± 2.03, respectively; adjusted mean difference-0.84, 95% confidence interval-1.61 to -0.06, P = 0.036). and there was no significant difference in AMS incidence between the two groups (25.0% vs 28.57%, P = 0.555). The RIPC group performed better than the control group in spatial memory span score (11[9-12] vs 10[7.5-11], P=0.025) and the passing digit (7[6-7.5] vs 6[5-7], P= 0.001). Spatial memory was significantly higher in the high-altitude RIPC group than in the low-altitude RIPC group (P<0.01). And the RIPC group obtained significantly lower self-reported sleep quality score (P = 0.024) and PSQI score (P = 0.031). CONCLUSIONS The RIPC treatment improved spatial memory and sleep quality in subjects exposed to acute hypoxic exposure and this may lead to improved performance at high altitude.
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Affiliation(s)
- Yu Wu
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Simin Zhou
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Yaling Li
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Pei Huang
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Zhifeng Zhong
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Huaping Dong
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Huaijun Tian
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China
| | - Shuai Jiang
- Department of Health, The 12th Integrated Training Base of Army, Chongqing, China
| | - Jiaxin Xie
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China.
| | - Peng Li
- Department of High Altitude Operational Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Army Medical University, Chongqing, China; Key Laboratory of High Altitude Medicine, Army Medical University, Chongqing, China.
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Effect of Remote Ischemic Preconditioning on the Incidence of Contrast Induced Nephropathy in Patients Undergoing Evar (Ripc-Evar Study). Ann Vasc Surg 2022; 86:338-348. [PMID: 35717008 DOI: 10.1016/j.avsg.2022.05.018] [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: 09/30/2021] [Revised: 04/26/2022] [Accepted: 05/08/2022] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Contrast induced nephropathy (CIN) is a major inconvenience in the use of iodinated contrast media (ICM) and it is associated with a significant increase in morbidity and mortality and cost of hospitalization. Remote ischemic preconditioning (RIPC) is a non-invasive and cost-effective tissue protection technique that has showed beneficial in decreasing renal insult in patients receiving intravascular contrast. AIM The primary outcome of this study is to evaluate the impact of RIPC on the incidence of CIN in patients undergoing endovascular aneurysm repair. MATERIAL AND METHODS Patients suffering from aortic aneurysm were recruited prior to the administration of iodinated contrast media. Randomization was used to assign patients into the control/RIPC groups. Biochemical parameters determined renal function before and after surgery in immediate (24-72 hours) and at 30 days' follow-up. RESULTS Of the 120 patients included in the study, 98,3% were male. Mean age was 73 years (range 56-87). Diabetes and chronic renal failure (considering eGFR<60) was present prior to administration of ICM in 29,16% and 38,33% respectively. RIPC was applied in 50% (n=60) of the patients. A total of 24,17% developed CIN regardless of fluid therapy, RIPC and other protective strategies. RIPC did not influence outcome in terms of incidence on CIN, serum creatinine, urea, estimated glomerular filtration (eGFR) or microalbuminuria in immediate postoperative period. However, the group of RIPC patients showed a statistically significant benefit in renal function in terms of serum creatinine (1,46 ± 0,3 vs 1,03 ± 0,5; p<0,001), urea (61,06 ± 27,5mg/dl vs 43,78 ± 12,9mg/dl; p=0,003) and an increase in eGFR (56,37 ± 23,4ml/min/1.73m2vs 72,85 ± 17,7ml/min/1.73m2; p=0,004) at 30 days follow-up. CONCLUSIONS RIPC seems to be a reasonable, effective and low-cost technique to alleviate effects of ICM on the renal parenchyma in EVAR procedures during short-term postoperative period.
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The ATX-LPA Axis Regulates Vascular Permeability during Cerebral Ischemic-Reperfusion. Int J Mol Sci 2022; 23:ijms23084138. [PMID: 35456953 PMCID: PMC9024554 DOI: 10.3390/ijms23084138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 11/29/2022] Open
Abstract
Endothelial permeability is a major complication that must be addressed during stroke treatment. Study of the mechanisms underlying blood−brain barrier (BBB) disruption and management of the hypoxic stress-induced permeability of the endothelium following reperfusion are both urgently needed for stroke management. Lysophosphatidic acid (LPA), a bioactive lipid essential for basic cellular functions, causes unfavorable outcomes during stroke progression. LPA-producing enzyme autotaxin (ATX) is regulated in ischemic stroke. We used an electrical cell-substrate impedance sensor (ECIS) to measure endothelial permeability. Mitochondrial bioenergetics were obtained using a Seahorse analyzer. AR-2 probe fluorescence assay was used to measure ATX activity. LPA increased endothelial permeability and reduced junctional protein expression in mouse brain microvascular endothelial cells (MBMEC). LPA receptor inhibitors Ki16425 and AM095 attenuated the LPA-induced changes in the endothelial permeability and junctional proteins. LPA significantly diminished mitochondrial function in MBMEC. ATX was upregulated (p < 0.05) in brain microvascular endothelial cells under hypoxic reperfusion. ATX activity and permeability were attenuated with the use of an ATX inhibitor in a mouse stroke model. The upregulation of ATX with hypoxic reperfusion leads to LPA production in brain endothelial cells favoring permeability. Inhibition of the ATX−LPA−LPAR axis could be therapeutically targeted in stroke to achieve better outcomes.
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Pattullo GG. Clinical implications of opioid-induced ventilatory impairment. Anaesth Intensive Care 2022; 50:52-67. [PMID: 35189729 DOI: 10.1177/0310057x211070292] [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: 11/15/2022]
Abstract
Opioid-induced ventilatory impairment is the primary mechanism of harm from opioid use. Opioids suppress the activity of the central respiratory centres and are sedating, leading to impairment of alveolar ventilation.Respiratory physiological changes induced with acute opioid use include depression of the hypercapnic ventilatory response and hypoxic ventilatory response. In chronic opioid use a compensatory increase in hypoxic ventilatory response maintains ventilation and contributes to the onset of sleep-disordered breathing patterns of central sleep apnoea and ataxic breathing. Supplemental oxygen use in those at risk of opioid-induced ventilatory impairment requires careful consideration by the clinician to prevent failure to detect hypoventilation, if oximetry is being relied on, and the overriding of hypoxic ventilatory drive. Obstructive sleep apnoea and opioid-induced ventilatory impairment are frequently associated, with this interrelationship being complex and often unpredictable. Monitoring the patient for opioid-induced ventilatory impairment poses challenges in the areas of reliability, avoidance of alarm fatigue, cost, and personnel demands. Many situations remain in which patients cannot be provided effective analgesia without opioids, and for these the clinician requires a comprehensive knowledge of opioid-induced ventilatory impairment.
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Affiliation(s)
- Gavin G Pattullo
- Department of Anaesthesia and Pain Management, Royal North Shore Hospital, St Leonards, Australia
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Kirasirova EA, Frolkina EA, Rybalchenko IE, Tyutina SI. [Chronic respiratory failure correction in cicatricial laryngeal and tracheal stenosis using helium-oxygen mixture]. Vestn Otorinolaringol 2022; 87:63-70. [PMID: 36107183 DOI: 10.17116/otorino20228704163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The article provides a review of the literature on the development of chronic respiratory failure in patients with chronic cicatricial stenosis of the larynx and cervical trachea. The authors provide data on the etiology, pathogenetic features of the course of cicatricial stenosis of the larynx and trachea, the reasons for the development of chronic respiratory failure, the effect of hypoxemia on general metabolic processes in the body and on regeneration processes, as well as on methods of their correction and improvement of the postoperative period. The methods of respiratory impact on chronic respiratory failure in these patients are considered, based on the experience of a number of researchers and technical advances in recent years.
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Affiliation(s)
- E A Kirasirova
- Pirogov Russian National Research Medical University, Moscow, Russia
- Sverzhevsky Research Clinical Institute of Otorhinolaryngology, Moscow, Russia
| | - E A Frolkina
- Sverzhevsky Research Clinical Institute of Otorhinolaryngology, Moscow, Russia
| | | | - S I Tyutina
- Sverzhevsky Research Clinical Institute of Otorhinolaryngology, Moscow, Russia
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Cardiac Surgery Associated AKI Prevention Strategies and Medical Treatment for CSA-AKI. J Clin Med 2021; 10:jcm10225285. [PMID: 34830567 PMCID: PMC8618011 DOI: 10.3390/jcm10225285] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/03/2021] [Accepted: 11/08/2021] [Indexed: 12/29/2022] Open
Abstract
Acute kidney injury (AKI) is common after cardiac surgery. To date, there are no specific pharmacological therapies. In this review, we summarise the existing evidence for prevention and management of cardiac surgery-associated AKI and outline areas for future research. Preoperatively, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers should be withheld and nephrotoxins should be avoided to reduce the risk. Intraoperative strategies include goal-directed therapy with individualised blood pressure management and administration of balanced fluids, the use of circuits with biocompatible coatings, application of minimally invasive extracorporeal circulation, and lung protective ventilation. Postoperative management should be in accordance with current KDIGO AKI recommendations.
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Neckář J, Alánová P, Olejníčková V, Papoušek F, Hejnová L, Šilhavý J, Behuliak M, Bencze M, Hrdlička J, Vecka M, Jarkovská D, Švíglerová J, Mistrová E, Štengl M, Novotný J, Ošťádal B, Pravenec M, Kolář F. Excess ischemic tachyarrhythmias trigger protection against myocardial infarction in hypertensive rats. Clin Sci (Lond) 2021; 135:2143-2163. [PMID: 34486670 DOI: 10.1042/cs20210648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/17/2021] [Accepted: 09/03/2021] [Indexed: 11/17/2022]
Abstract
Increased level of C-reactive protein (CRP) is a risk factor for cardiovascular diseases, including myocardial infarction and hypertension. Here, we analyzed the effects of CRP overexpression on cardiac susceptibility to ischemia/reperfusion (I/R) injury in adult spontaneously hypertensive rats (SHR) expressing human CRP transgene (SHR-CRP). Using an in vivo model of coronary artery occlusion, we found that transgenic expression of CRP predisposed SHR-CRP to repeated and prolonged ventricular tachyarrhythmias. Excessive ischemic arrhythmias in SHR-CRP led to a significant reduction in infarct size (IS) compared with SHR. The proarrhythmic phenotype in SHR-CRP was associated with altered heart and plasma eicosanoids, myocardial composition of fatty acids (FAs) in phospholipids, and autonomic nervous system imbalance before ischemia. To explain unexpected IS-limiting effect in SHR-CRP, we performed metabolomic analysis of plasma before and after ischemia. We also determined cardiac ischemic tolerance in hearts subjected to remote ischemic perconditioning (RIPer) and in hearts ex vivo. Acute ischemia in SHR-CRP markedly increased plasma levels of multiple potent cardioprotective molecules that could reduce IS at reperfusion. RIPer provided IS-limiting effect in SHR that was comparable with myocardial infarction observed in naïve SHR-CRP. In hearts ex vivo, IS did not differ between the strains, suggesting that extra-cardiac factors play a crucial role in protection. Our study shows that transgenic expression of human CRP predisposes SHR-CRP to excess ischemic ventricular tachyarrhythmias associated with a drop of pump function that triggers myocardial salvage against lethal I/R injury likely mediated by protective substances released to blood from hypoxic organs and tissue at reperfusion.
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Affiliation(s)
- Jan Neckář
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- Centre for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Petra Alánová
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Veronika Olejníčková
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - František Papoušek
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Lucie Hejnová
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jan Šilhavý
- Laboratory of Genetics of Model Diseases, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Michal Behuliak
- Laboratory of Experimental Hypertension, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Michal Bencze
- Laboratory of Experimental Hypertension, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jaroslav Hrdlička
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Marek Vecka
- 4th Department of Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Dagmar Jarkovská
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Prague, Czech Republic
| | - Jitka Švíglerová
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Prague, Czech Republic
| | - Eliška Mistrová
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Prague, Czech Republic
| | - Milan Štengl
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Prague, Czech Republic
| | - Jiří Novotný
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Bohuslav Ošťádal
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Michal Pravenec
- Laboratory of Genetics of Model Diseases, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - František Kolář
- Laboratory of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
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Xie D, Wang J, Hu G, Chen C, Yang H, Ritter JK, Qu Y, Li N. Kidney-Targeted Delivery of Prolyl Hydroxylase Domain Protein 2 Small Interfering RNA with Nanoparticles Alleviated Renal Ischemia/Reperfusion Injury. J Pharmacol Exp Ther 2021; 378:235-243. [PMID: 34103333 PMCID: PMC11047054 DOI: 10.1124/jpet.121.000667] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 06/03/2021] [Indexed: 12/15/2022] Open
Abstract
Inhibition of hypoxia-inducible factor-prolyl hydroxylase (PHD) has been shown to protect against various kidney diseases. However, there are controversial reports on the effect of PHD inhibition in renoprotection. The present study determined whether delivery of PHD2 small interfering RNA (siRNA) using an siRNA carrier, folic acid (FA)-decorated polyamidoamine dendrimer generation 5 (G5-FA), would mainly target kidneys and protect against renal ischemia/reperfusion injury (I/R). The renal I/R was generated by clipping the renal pedicle for 30 minutes in uninephrectomized mice. Mice were sacrificed 48 hours after I/R. Normal saline or G5-FA complexed with control or PHD2 siRNA was injected via tail vein 24 hours before ischemia. After the injection of near-infrared fluorescent dye-labeled G5-FA, the fluorescence was mainly detected in kidneys but not in other organs. The reduction of PHD2 mRNA and protein was only observed in kidneys but not in other organs after injection of PHD2-siRNA-G5-FA complex. The injection of PHD2-siRNA-G5-FA significantly alleviated renal I/R injury, as shown by the inhibition of increases in serum creatinine and blood urea nitrogen, the blockade of increases in kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin, and the improvement of histologic damage compared with mice treated with control siRNA. PHD2 siRNA can be delivered specifically into kidneys using G5-FA, and that local knockdown of PHD2 gene expression within the kidney alleviates renal I/R injury. Therefore, G5-FA is an efficient siRNA carrier to deliver siRNA into the kidney, and that local inhibition of PHD2 within the kidney may be a potential strategy for the management of acute I/R injury. SIGNIFICANCE STATEMENT: Folic acid (FA)-decorated polyamidoamine dendrimer generation 5 (G5-FA) was demonstrated to be an effective carrier to deliver small interfering RNA (siRNA) into kidneys. Delivery of prolyl hydroxylase domain protein 2 siRNA with G5-FA effectively protected the kidneys against the acute renal ischemia/reperfusion injury.
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Affiliation(s)
- Dengpiao Xie
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Juan Wang
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Gaizun Hu
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Chaoling Chen
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Hu Yang
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Joseph K Ritter
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Yun Qu
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
| | - Ningjun Li
- Department of Pharmacology & Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia (D.X., G.H., C.C., J.K.R., N.L.); College of Biomedical Engineering, Sichuan University, Chengdu, China (J.W.); Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri (H.Y.); and Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia (Y.Q.)
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10
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Knutson AK, Williams AL, Boisvert WA, Shohet RV. HIF in the heart: development, metabolism, ischemia, and atherosclerosis. J Clin Invest 2021; 131:137557. [PMID: 34623330 DOI: 10.1172/jci137557] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The heart forms early in development and delivers oxygenated blood to the rest of the embryo. After birth, the heart requires kilograms of ATP each day to support contractility for the circulation. Cardiac metabolism is omnivorous, utilizing multiple substrates and metabolic pathways to produce this energy. Cardiac development, metabolic tuning, and the response to ischemia are all regulated in part by the hypoxia-inducible factors (HIFs), central components of essential signaling pathways that respond to hypoxia. Here we review the actions of HIF1, HIF2, and HIF3 in the heart, from their roles in development and metabolism to their activity in regeneration and preconditioning strategies. We also discuss recent work on the role of HIFs in atherosclerosis, the precipitating cause of myocardial ischemia and the leading cause of death in the developed world.
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11
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Hepatic cell mobilization for protection against ischemic myocardial injury. Sci Rep 2021; 11:15830. [PMID: 34349157 PMCID: PMC8339068 DOI: 10.1038/s41598-021-94170-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 06/29/2021] [Indexed: 11/29/2022] Open
Abstract
The heart is capable of activating protective mechanisms in response to ischemic injury to support myocardial survival and performance. These mechanisms have been recognized primarily in the ischemic heart, involving paracrine signaling processes. Here, we report a distant cardioprotective mechanism involving hepatic cell mobilization to the ischemic myocardium in response to experimental myocardial ischemia–reperfusion (MI-R) injury. A parabiotic mouse model was generated by surgical skin-union of two mice and used to induce bilateral MI-R injury with unilateral hepatectomy, establishing concurrent gain- and loss-of-hepatic cell mobilization conditions. Hepatic cells, identified based on the cell-specific expression of enhanced YFP, were found in the ischemic myocardium of parabiotic mice with intact liver (0.2 ± 0.1%, 1.1 ± 0.3%, 2.7 ± 0.6, and 0.7 ± 0.4% at 1, 3, 5, and 10 days, respectively, in reference to the total cell nuclei), but not significantly in the ischemic myocardium of parabiotic mice with hepatectomy (0 ± 0%, 0.1 ± 0.1%, 0.3 ± 0.2%, and 0.08 ± 0.08% at the same time points). The mobilized hepatic cells were able to express and release trefoil factor 3 (TFF3), a protein mitigating MI-R injury as demonstrated in TFF3−/− mice (myocardium infarcts 17.6 ± 2.3%, 20.7 ± 2.6%, and 15.3 ± 3.8% at 1, 5, and 10 days, respectively) in reference to wildtype mice (11.7 ± 1.9%, 13.8 ± 2.3%, and 11.0 ± 1.8% at the same time points). These observations suggest that MI-R injury can induce hepatic cell mobilization to support myocardial survival by releasing TFF3.
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12
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Wish JB, Eckardt KU, Kovesdy CP, Fishbane S, Spinowitz BS, Berns JS. Hypoxia-Inducible Factor Stabilization as an Emerging Therapy for CKD-Related Anemia: Report From a Scientific Workshop Sponsored by the National Kidney Foundation. Am J Kidney Dis 2021; 78:709-718. [PMID: 34332007 DOI: 10.1053/j.ajkd.2021.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/01/2021] [Indexed: 12/16/2022]
Abstract
The National Kidney Foundation convened an interdisciplinary international workshop in March 2019 to discuss the potential role of a new class of agents for the treatment of anemia in patients with chronic kidney disease (CKD): the hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs). International experts with expertise in physiology, biochemistry, structural chemistry, translational medicine and clinical management of anemia participated. Participants reviewed the unmet needs of current anemia treatment, the biology of hypoxia-inducible factor, the pharmacology of prolyl hydroxylase inhibitors, and the results of phase 2 clinical trials of HIF-PHIs among patients with both non-dialysis dependent and dialysis-dependent CKD. The results of key phase 3 clinical trials of HIF-PHIs in the public domain as of this writing are also presented in this article although they appeared after the workshop was completed. Participants in the workshop developed a number of recommendations for further examination of HIF-PHIs which are summarized in this article and include long-term safety issues, potential benefits, and practical considerations for implementation including patient and provider education.
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Affiliation(s)
- Jay B Wish
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA.
| | - Kai-Uwe Eckardt
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Csaba P Kovesdy
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Steven Fishbane
- Department of Medicine, Zucker School of Medicine at Hofstra/Northwell, Great Neck, NY, USA
| | - Bruce S Spinowitz
- Department of Medicine, New York Hospital Queens, Cornell University Medical Center, Queens, NY, USA
| | - Jeffrey S Berns
- Department of Medicine, Perelman School of Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
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13
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Wang L, Tang Y, He H, Wei W. Liraglutide restores late cardioprotective effects of remote preconditioning in diabetic rats via activation of hydrogen sulfide and nuclear factor erythroid 2-related factor 2 signaling pathway. Acta Cir Bras 2021; 36:e360207. [PMID: 33656046 PMCID: PMC7909944 DOI: 10.1590/acb360207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 01/23/2021] [Indexed: 02/07/2023] Open
Abstract
PURPOSE The present study explored the influence of liraglutide on remote preconditioning-mediated cardioprotection in diabetes mellitus along with the role of nuclear factor erythroid 2-related factor 2 (Nrf2), hypoxia inducible factor (HIF-1α) and hydrogen sulfide (H2S). METHODS Streptozotocin was given to rats to induce diabetes mellitus and rats were kept for eight weeks. Four cycles of ischemia and reperfusion were given to hind limb to induce remote preconditioning. After 24 h, hearts were isolated and subjected to 30 min of ischemia and 120 min of reperfusion on Langendorff system. Liraglutide was administered along with remote preconditioning. Cardiac injury was assessed by measuring the release of creatine kinase (CK-MB), cardiac troponin (cTnT) and development of left ventricular developed pressure. After ischemia-reperfusion, hearts were homogenized to measure the nuclear cytoplasmic ratio of Nrf2, H2S and HIF-1α levels. RESULTS In diabetic rats, there was more pronounced injury and the cardioprotective effects of remote preconditioning were not observed. Administration of liraglutide restored the cardioprotective effects of remote preconditioning in a dose-dependent manner. Moreover, liraglutide increased the Nrf2, H2S and HIF-1α levels in remote preconditioning-subjected diabetic rats. CONCLUSIONS Liraglutide restores the lost cardioprotective effects of remote preconditioning in diabetes by increasing the expression of Nrf2, H2S and HIF-1α.
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Affiliation(s)
| | - Yinyan Tang
- The Forth People’s Hospital of Yongzhou, China
| | - Huimin He
- The Forth People’s Hospital of Yongzhou, China
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14
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Increasing Oxygen Partial Pressures Induce a Distinct Transcriptional Response in Human PBMC: A Pilot Study on the "Normobaric Oxygen Paradox". Int J Mol Sci 2021; 22:ijms22010458. [PMID: 33466421 PMCID: PMC7796168 DOI: 10.3390/ijms22010458] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/31/2020] [Accepted: 01/01/2021] [Indexed: 02/07/2023] Open
Abstract
The term “normobaric oxygen paradox” (NOP), describes the response to the return to normoxia after a hyperoxic event, sensed by tissues as oxygen shortage, and resulting in up-regulation of the Hypoxia-inducible factor 1α (HIF-1α) transcription factor activity. The molecular characteristics of this response have not been yet fully characterized. Herein, we report the activation time trend of oxygen-sensitive transcription factors in human peripheral blood mononuclear cells (PBMCs) obtained from healthy subjects after one hour of exposure to mild (MH), high (HH) and very high (VHH) hyperoxia, corresponding to 30%, 100%, 140% O2, respectively. Our observations confirm that MH is perceived as a hypoxic stress, characterized by the activation of HIF-1α and Nuclear factor (erythroid-derived 2)-like 2 (NRF2), but not Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB). Conversely, HH is associated to a progressive loss of NOP response and to an increase in oxidative stress leading to NRF2 and NF-kB activation, accompanied by the synthesis of glutathione (GSH). After VHH, HIF-1α activation is totally absent and oxidative stress response, accompanied by NF-κB activation, is prevalent. Intracellular GSH and Matrix metallopeptidase 9 (MMP-9) plasma levels parallel the transcription factors activation pattern and remain elevated throughout the observation time. In conclusion, our study confirms that, in vivo, the return to normoxia after MH is sensed as a hypoxic trigger characterized by HIF-1α activation. On the contrary, HH and VHH induce a shift toward an oxidative stress response, characterized by NRF2 and NF-κB activation in the first 24 h post exposure.
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15
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Harman JC, Guidry JJ, Gidday JM. Intermittent Hypoxia Promotes Functional Neuroprotection from Retinal Ischemia in Untreated First-Generation Offspring: Proteomic Mechanistic Insights. Invest Ophthalmol Vis Sci 2020; 61:15. [PMID: 32910134 PMCID: PMC7488620 DOI: 10.1167/iovs.61.11.15] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 08/03/2020] [Indexed: 12/31/2022] Open
Abstract
Purpose Stress can lead to short- or long-term changes in phenotype. Accumulating evidence also supports the transmission of maladaptive phenotypes, induced by adverse stressors, through the germline to manifest in subsequent generations, providing a novel mechanistic basis for the heritability of disease. In the present study in mice, we tested the hypothesis that repeated presentations of a nonharmful conditioning stress, demonstrated previously to protect against retinal ischemia, will also provide ischemic protection in the retinae of their untreated, first-generation (F1) adult offspring. Methods Swiss-Webster ND4 outbred mice were mated following a 16-week period of brief, every-other-day conditioning exposures to mild systemic hypoxia (repetitive hypoxic conditioning, RHC). Retinae of their 5-month-old F1 progeny were subjected to unilateral ischemia. Scotopic electroretinography quantified postischemic outcomes. The injury-resilient retinal proteome was revealed by quantitative mass spectrometry, and bioinformatic analyses identified the biochemical pathways and networks in which these differentially expressed proteins operate. Results Significant resilience to injury in both sexes was documented in F1 mice derived from RHC-treated parents, relative to matched F1 adult progeny derived from normoxic control parents. Ischemia-induced increases and decreases in the expression of many visual transduction proteins that are integral to photoreceptor function were abrogated by parental RHC, providing a molecular basis for the observed functional protection. Conclusions Our proteomic analyses provided mechanistic insights into the molecular manifestation of the inherited, injury-resilient phenotype. To our knowledge, this is the first study in a mammalian model documenting the reprogramming of heritability to promote disease resilience in the next generation.
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Affiliation(s)
- Jarrod C. Harman
- Department of Ophthalmology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
- Department of Biochemistry and Molecular Biology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
- Neuroscience Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
| | - Jessie J. Guidry
- Department of Biochemistry and Molecular Biology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
- LSUHSC Proteomics Core Facility, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
| | - Jeffrey M. Gidday
- Department of Ophthalmology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
- Department of Biochemistry and Molecular Biology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
- Neuroscience Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
- Department of Physiology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States
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16
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Abstract
Although kidney oxygen tensions are heterogenous, and mostly below renal vein level, the nephron is highly dependent on aerobic metabolism for active tubular transport. This renders the kidney particularly susceptible to hypoxia, which is considered a main characteristic and driver of acute and chronic kidney injury, albeit the evidence supporting this assumption is not entirely conclusive. Kidney transplants are exposed to several conditions that may interfere with the balance between oxygen supply and consumption, and enhance hypoxia and hypoxic injury. These include conditions leading to and resulting from brain death of kidney donors, ischemia and reperfusion during organ donation, storage and transplantation, postoperative vascular complications, vasoconstriction induced by immunosuppression, and impaired perfusion resulting from interstitial edema, inflammation, and fibrosis. Acute graft injury, the immediate consequence of hypoxia and reperfusion, results in delayed graft function and increased risk of chronic graft failure. Although current strategies to alleviate hypoxic/ischemic graft injury focus on limiting injury (eg, by reducing cold and warm ischemia times), experimental evidence suggests that preconditioning through local or remote ischemia, or activation of the hypoxia-inducible factor pathway, can decrease hypoxic injury. In combination with ex vivo machine perfusion such approaches hold significant promise for improving transplantation outcomes.
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Affiliation(s)
- Christian Rosenberger
- Department of Nephrology and Medical Intensive Care, Charité Universitaetsmedizin Berlin, Berlin, Germany.
| | - Kai-Uwe Eckardt
- Department of Nephrology and Medical Intensive Care, Charité Universitaetsmedizin Berlin, Berlin, Germany
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17
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Heyman SN, Khamaisi M, Zorbavel D, Rosen S, Abassi Z. Role of Hypoxia in Renal Failure Caused by Nephrotoxins and Hypertonic Solutions. Semin Nephrol 2020; 39:530-542. [PMID: 31836036 DOI: 10.1016/j.semnephrol.2019.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hypoxia plays a role in the pathogenesis of acute kidney injury under diverse clinical settings, including nephrotoxicity. Although some nephrotoxins exert direct renal parenchymal injury, likely with consequent altered oxygenation, others primarily reduce renal parenchymal oxygenation, leading to hypoxic tubular damage. As outlined in this review, nephrotoxin-related renal hypoxia may result from an altered renal oxygen supply (cyclosporine), enhanced oxygen consumption for tubular transport (agents inducing osmotic diuresis), or their combination (nonsteroidal anti-inflammatory drugs, radiocontrast agents, and others). Most agents causing hypoxic renal injury further supress physiologic low medullary Po2, in which a limited regional blood supply barely matches the intense regional tubular transport and oxygen consumption. The medullary tubular transport and blood supply are finely matched, securing oxygen sufficiency. Predisposition to hypoxia-mediated nephrotoxicity by medical conditions, such as chronic kidney disease or diabetes, may be explained by malfunctioning of control systems that normally maintain medullary oxygenation. However, this propensity may be diminished by hypoxia-mediated adaptive responses governed by hypoxia-inducible factors. Recent reports have suggested that inhibitors of sodium-glucose cotransporters and the administration of hypertonic saline may be added to the growing list of common therapeutic interventions that intensify medullary hypoxia, and potentially could lead to hypoxic acute kidney injury.
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Affiliation(s)
- Samuel N Heyman
- Department of Medicine, Hadassah Hebrew University Hospital, Mt. Scopus, Jerusalem, Israel.
| | - Mogher Khamaisi
- Department of Medicine D, Rambam Health Care Campus, Haifa, Israel; Institute of Endocrinology, Diabetes and Metabolism, Rambam Health Care Campus, Haifa, Israel
| | - Danny Zorbavel
- Department of Medicine D, Rambam Health Care Campus, Haifa, Israel
| | - Seymour Rosen
- Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA; Department of Pathology, Harvard Medical School, Boston, MA
| | - Zaid Abassi
- Department of Physiology, Ruth and Bruce Rappaport Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel; Department of Laboratory Medicine, Rambam Health Care Campus, Haifa, Israel
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18
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Cho YJ, Kim WH. Perioperative Cardioprotection by Remote Ischemic Conditioning. Int J Mol Sci 2019; 20:ijms20194839. [PMID: 31569468 PMCID: PMC6801656 DOI: 10.3390/ijms20194839] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 09/11/2019] [Accepted: 09/27/2019] [Indexed: 12/24/2022] Open
Abstract
Remote ischemic conditioning has been investigated for cardioprotection to attenuate myocardial ischemia/reperfusion injury. In this review, we provide a comprehensive overview of the current knowledge of the signal transduction pathways of remote ischemic conditioning according to three stages: Remote stimulus from source organ; protective signal transfer through neuronal and humoral factors; and target organ response, including myocardial response and coronary vascular response. The neuronal and humoral factors interact on three levels, including stimulus, systemic, and target levels. Subsequently, we reviewed the clinical studies evaluating the cardioprotective effect of remote ischemic conditioning. While clinical studies of percutaneous coronary intervention showed relatively consistent protective effects, the majority of multicenter studies of cardiac surgery reported neutral results although there have been several promising initial trials. Failure to translate the protective effects of remote ischemic conditioning into cardiac surgery may be due to the multifactorial etiology of myocardial injury, potential confounding factors of patient age, comorbidities including diabetes, concomitant medications, and the coadministered cardioprotective general anesthetic agents. Given the complexity of signal transfer pathways and confounding factors, further studies should evaluate the multitarget strategies with optimal measures of composite outcomes.
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Affiliation(s)
- Youn Joung Cho
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Korea.
| | - Won Ho Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Korea.
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19
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Kaufman CL, Cascalho M, Ozyurekoglu T, Jones CM, Ramirez A, Roberts T, Tien HY, Moreno R, Galvis E, Tsai TM, Palazzo M, Farner S, Platt JL. The role of B cell immunity in VCA graft rejection and acceptance. Hum Immunol 2019; 80:385-392. [DOI: 10.1016/j.humimm.2019.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 03/01/2019] [Accepted: 03/02/2019] [Indexed: 12/12/2022]
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20
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Yang K, Leslie KG, Kim SY, Kalionis B, Chrzanowski W, Jolliffe KA, New EJ. Tailoring the properties of a hypoxia-responsive 1,8-naphthalimide for imaging applications. Org Biomol Chem 2019; 16:619-624. [PMID: 29302671 DOI: 10.1039/c7ob03164e] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Sensing hypoxia in tissues and cell models can provide insights into its role in disease states and cell development. Fluorescence imaging is a minimally-invasive method of visualising hypoxia in many biological systems. Here we present a series of improved bioreductive fluorescent sensors based on a nitro-naphthalimide structure, in which selectivity, photophysical properties, toxicity and cellular uptake are tuned through structural modifications. This new range of compounds provides improved probes for imaging and monitoring hypoxia, customised for a range of different applications. Studies in monolayers show the different reducing capabilities of hypoxia-resistant and non-resistant cell lines, and studies in tumour models show successful staining of the hypoxic region.
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Affiliation(s)
- Kylie Yang
- School of Chemistry, The University of Sydney, NSW, 2006 Australia
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21
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Liu Z, Barber C, Gupta A, Wan L, Won YW, Furenlid LR, Chen Q, Desai AA, Zhao M, Bull DA, Unger EC, Martin DR. Imaging assessment of cardioprotection mediated by a dodecafluoropentane oxygen-carrier administered during myocardial infarction. Nucl Med Biol 2019; 70:67-77. [PMID: 30772168 DOI: 10.1016/j.nucmedbio.2019.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/18/2018] [Accepted: 01/14/2019] [Indexed: 01/25/2023]
Abstract
INTRODUCTION The objective of this study was to investigate the cardioprotective effects of a dodecafluoropentane (DDFP)-based perfluorocarbon emulsion (DDFPe) as an artificial carrier for oxygen delivery to ischemic myocardium, using 99mTc-duramycin SPECT imaging. METHODS Rat hearts with Ischemia-reperfusion (I/R) was prepared by coronary ligation for 45-min followed by reperfusion. The feasibility of 99mTc-duramycin in detecting myocardial I/R injury and its kinetic profile were first verified in the ischemic hearts with 2-h reperfusion (n = 6). DDFPe (0.6 mL/kg) was intravenously administered at 10 min after coronary ligation in fifteen rats and saline was given in thirteen rats as controls. 99mTc-duramycin SPECT images were acquired in the DDFPe-treated hearts and saline controls at 2-h (DDFPe-2 h, n = 7 and Saline-2 h, n = 6) or 24-h (DDFPe-24 h, n = 8 and Saline-24 h, n = 7) of reperfusion. RESULTS SPECT images, showing "hot-spot" 99mTc-duramycin uptake in the ischemic myocardium, exhibited significantly lower radioactive retention and smaller hot-spot size in the DDFPe-2 h and DDFPe-24 h hearts compared to controls. The infarcts in the Saline-24 h hearts extended significantly relative to measurements in the Saline-2 h. The extension of infarct size did not reach a statistical difference between the DDFPe-2 h and DDFPe-24 h hearts. Ex vivo measurement of 99mTc-duramycin activity (%ID/g) was lower in the ischemic area of DDFPe-2 h and DDFPe-24 h than that of the Saline-2 h and Saline-24 h hearts (P < 0.05). The area of injured myocardium, delineated by the uptake of 99mTc-duramycin, extended more substantially outside the infarct zone in the controls. CONCLUSIONS Significant reduction in myocardial I/R injury, as assessed by 99mTc-duramycin cell death imaging and histopathological analysis, was induced by DDFPe treatment after acute myocardial ischemia. 99mTc-duramycin imaging can reveal myocardial cell death in ischemic hearts and may provide a tool for the non-invasive assessment of cardioprotective interventions.
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Affiliation(s)
- Zhonglin Liu
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America.
| | - Christy Barber
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America
| | - Akash Gupta
- Division of Cardiology of Department of Medicine, University of Arizona, Tucson, AZ, United States of America
| | - Li Wan
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America
| | - Young-Wook Won
- Division of Cardiothoracic Surgery of Department of Surgery, University of Arizona, Tucson, AZ, United States of America
| | - Lars R Furenlid
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America
| | - Qin Chen
- Department of Pharmacology, University of Arizona, Tucson, AZ, United States of America
| | - Ankit A Desai
- Division of Cardiology of Department of Medicine, University of Arizona, Tucson, AZ, United States of America
| | - Ming Zhao
- Feinberg School of Medicine, Northwestern University, Chicago, IL, United States of America
| | - David A Bull
- Division of Cardiothoracic Surgery of Department of Surgery, University of Arizona, Tucson, AZ, United States of America
| | - Evan C Unger
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America; NuvOx Pharma, LLC., Tucson, AZ, United States of America
| | - Diego R Martin
- Department of Medical Imaging, University of Arizona, Tucson, AZ, United States of America.
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22
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Lanigan SM, O'Connor JJ. Prolyl hydroxylase domain inhibitors: can multiple mechanisms be an opportunity for ischemic stroke? Neuropharmacology 2018; 148:117-130. [PMID: 30578795 DOI: 10.1016/j.neuropharm.2018.12.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 12/19/2022]
Abstract
Stroke and cerebrovascular disease are now the fifth most common cause of death behind other diseases such as heart, cancer and respiratory disease and accounts for approximately 40-50 fatalities per 100,000 people each year in the United States. Currently the only therapy for acute stroke, is intravenous administration of tissue plasminogen activator which was approved in 1996 by the FDA. Surprisingly no new treatments have come on the market since, although endovascular mechanical thrombectomy is showing promising results in trials. Recently focus has shifted towards a preventative therapy rather than trying to reverse or limit the amount of damage occurring following stroke onset. During one of the components of ischemia, hypoxia, a number of physiological changes occur within neurons which include the stabilization of hypoxia-inducible factors. The activity of these proteins is regulated by O2, Fe2+, 2-OG and ascorbate-dependant hydroxylases which contain prolyl-4-hydroxylase domains (PHDs). PHD inhibitors are capable of pharmacologically activating the body's own endogenous adaptive response to low levels of oxygen and have therefore become an attractive therapeutic target for treating ischemia. They have been widely used in the periphery and have been shown to have a preconditioning and protective effect against a later and more severe ischemic insult. Currently there are a number of these agents in phase 1, 2 and 3 clinical trials for the treatment of anemia. In this review we assess the neuroprotective effects of PHD inhibitors, including dimethyloxalylglycine and deferoxamine and suggest that not all of their effects in the CNS are HIF-dependent. Unravelling new roles and a better understanding of the function of PHD inhibitors in the CNS may be of great benefit especially when investigating their use in the treatment of stroke and other ischemic diseases.
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Affiliation(s)
- Sinead M Lanigan
- UCD School of Biomolecular & Biomedical Science, UCD Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - John J O'Connor
- UCD School of Biomolecular & Biomedical Science, UCD Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
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Farré R, Almendros I, Montserrat JM, Gozal D, Navajas D. Gas Partial Pressure in Cultured Cells: Patho-Physiological Importance and Methodological Approaches. Front Physiol 2018; 9:1803. [PMID: 30618815 PMCID: PMC6300470 DOI: 10.3389/fphys.2018.01803] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/29/2018] [Indexed: 12/19/2022] Open
Abstract
Gas partial pressures within the cell microenvironment are one of the key modulators of cell pathophysiology. Indeed, respiratory gases (O2 and CO2) are usually altered in respiratory diseases and gasotransmitters (CO, NO, H2S) have been proposed as potential therapeutic agents. Investigating the pathophysiology of respiratory diseases in vitro mandates that cultured cells are subjected to gas partial pressures similar to those experienced by each cell type in its native microenvironment. For instance, O2 partial pressures range from ∼13% in the arterial endothelium to values as low as 2-5% in cells of other healthy tissues and to less than 1% in solid tumor cells, clearly much lower values than those used in conventional cell culture research settings (∼19%). Moreover, actual cell O2 partial pressure in vivo changes with time, at considerably different timescales as illustrated by tumors, sleep apnea, or mechanical ventilation. Unfortunately, the conventional approach to modify gas concentrations at the above culture medium precludes the tight and exact control of intra-cellular gas levels to realistically mimic the natural cell microenvironment. Interestingly, well-controlled cellular application of gas partial pressures is currently possible through commercially available silicone-like material (PDMS) membranes, which are biocompatible and have a high permeability to gases. Cells are seeded on one side of the membrane and tailored gas concentrations are circulated on the other side of the membrane. Using thin membranes (50-100 μm) the value of gas concentration is instantaneously (<0.5 s) transmitted to the cell microenvironment. As PDMS is transparent, cells can be concurrently observed by conventional or advanced microscopy. This procedure can be implemented in specific-purpose microfluidic devices and in settings that do not require expensive or complex technologies, thus making the procedure readily implementable in any cell biology laboratory. This review describes the gas composition requirements for a cell culture in respiratory research, the limitations of current experimental settings, and also suggests new approaches to better control gas partial pressures in a cell culture.
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Affiliation(s)
- Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Josep M. Montserrat
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
- Sleep Lab, Hospital Clinic of Barcelona, Barcelona, Spain
| | - David Gozal
- Department of Child Health, University of Missouri School of Medicine, Columbia, MO, United States
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institute for Bioengineering of Catalonia, Barcelona Institute of Science and Technology, Barcelona, Spain
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Elagin V, Bratchikov O, Zatolokina M. Correction of morphofunctional disorders with asialoerythropoietin and selective inhibitor of arginase II KUD975 in cases of ischemic kidney damage in the experiment. RESEARCH RESULTS IN PHARMACOLOGY 2018. [DOI: 10.3897/rrpharmacology.4.31846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Introduction: Acute kidney injury (AKI), which is based on ischemic-reperfusion damage, is a widespread life-threatening condition and remains a serious public health problem with a high mortality rate among patients. Despite significant advances in various areas of medicine, the prevention and correction of ischemic-reperfusion kidney damage are still far from being at the desired level. Pharmacological preconditioning and the use of endothelioprotectors are promising areas in this field, therefore the purpose of this study was to analyze the nephroprotective properties of asialoerythropoietin and selective inhibitor of arginase II KUD975 in ischemic kidney damage in the experiment.Materials and methods: The study was performed on 260 white adult male Wistar rats, each weighing 180-220 g. Ischemic-reperfusion damage was simulated by applying a clamp on the renal leg for 40 minutes. To determine a degree of correction caused by morphofunctional disorders traditional functional, biochemical and morphological criteria were used.Results and discussion: When administering asialoerythropoietin and selective inhibitor of arginase II KUD975, there is observed an improvement in the glomerular filtration and microcirculation in the kidneys, decrease in the concentration of creatinine and urea, a decrease in fractional excretion of sodium and improvement in the histological pattern at different periods. The most pronounced nephroprotective effects are observed in the combined use of the test pharmacological agents, which are superior to such used in a monotherapy. The use of glibenclamide and L-NAME against the background of the correction of the pathology caused by asialoerythropoietin completely eliminates its positive effects. When glibenclamide and L-NAME are used against the background of correction of the pathology caused by the selective inhibitor of arginase II KUD975, its positive effects are completely eliminated by L-NAME. Glibenclamide does not eliminate positive effects.Conclusions: The results of the experiment prove the presence of pronounced nephroprotective properties of asialoerythropoietin and selective inhibitor of arginase II KUD975 in ischemic kidney damage in the experiment. The most pronounced effects are observed in the combined use of these pharmacological agents. The leading role in causing the positive effects from asialoerythropoietin is played by the activation of K+ATP channels and the activation of eNOS. The leading role in causing the positive effects from the selective inhibitor of arginase II KUD975 is played by the activation of eNOS.
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Szalat A, Perlman A, Muszkat M, Khamaisi M, Abassi Z, Heyman SN. Can SGLT2 Inhibitors Cause Acute Renal Failure? Plausible Role for Altered Glomerular Hemodynamics and Medullary Hypoxia. Drug Saf 2018; 41:239-252. [PMID: 28952138 DOI: 10.1007/s40264-017-0602-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Sodium-glucose co-transporter-2 inhibitors (SGLT2i) provide outstanding long-term cardiovascular and renal protection in high-risk patients with type 2 diabetes mellitus. Yet, despite encouraging renal safety outcomes reported in the EMPA-REG study, scattered reports suggest that there might be a risk for acute kidney injury (AKI), which may occasionally be fatal or might require renal replacement therapy. Reduced trans-glomerular pressure with a modest decline in kidney function, an inherent characteristic of SGLT2i therapy, conceivably forms the basis for the long-term renal protection, resembling agents that block the renin-angiotensin-aldosterone (RAAS) axis. Yet, a major decline in kidney function occasionally occurs, often associated with an acute illness or with specific co-administered medications. SGLT2i may lead to AKI by (a) effective volume depletion, due to excessive diuresis, particularly in hemodynamically unstable and volume-depleted patients; (b) excessive decline in trans-glomerular pressure, specifically in patients on RAAS blockade; and (c) induction of renal medullary hypoxic injury, related to enhanced distal tubular transport, especially with concomitant use of agents impairing medullary oxygenation, such as non-steroidal anti-inflammatory drugs and radiocontrast agents. The risk of developing renal impairment with SGLT2i and the role of these suggested mechanisms are yet to be defined, as there are conflicting data and inconsistent reporting with the various agents currently in use.
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Affiliation(s)
- Auryan Szalat
- Department of Medicine, Hadassah Hebrew University Hospital, Mt. Scopus, P.O. Box 24035, 91240, Jerusalem, Israel
| | - Amichai Perlman
- Department of Medicine, Hadassah Hebrew University Hospital, Mt. Scopus, P.O. Box 24035, 91240, Jerusalem, Israel
| | - Mordechai Muszkat
- Department of Medicine, Hadassah Hebrew University Hospital, Mt. Scopus, P.O. Box 24035, 91240, Jerusalem, Israel
| | - Mogher Khamaisi
- Department of Internal Medicine, Rambam Medical Center, Haifa, Israel
| | - Zaid Abassi
- Department of Physiology and Systems Biology, The Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,Department of Laboratory Medicine, Rambam Health Campus, Haifa, Israel
| | - Samuel N Heyman
- Department of Medicine, Hadassah Hebrew University Hospital, Mt. Scopus, P.O. Box 24035, 91240, Jerusalem, Israel.
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26
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Elabd C, Ichim TE, Miller K, Anneling A, Grinstein V, Vargas V, Silva FJ. Comparing atmospheric and hypoxic cultured mesenchymal stem cell transcriptome: implication for stem cell therapies targeting intervertebral discs. J Transl Med 2018; 16:222. [PMID: 30097061 PMCID: PMC6086019 DOI: 10.1186/s12967-018-1601-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 08/04/2018] [Indexed: 02/07/2023] Open
Abstract
Background Mesenchymal stem cells (MSCs) represent an attractive avenue for cellular therapies targeting degenerative diseases. MSC in vitro expansion is required in order to obtain therapeutic numbers during the manufacturing process. It is known that culture conditions impact cellular properties and behavior after in vivo transplantation. In this study, we aimed at evaluating the benefit of hypoxic culturing of human bone marrow derived mesenchymal stem cells on cell fitness and whole genome expression and discussed its implication on cellular therapies targeting orthopedic diseases such as chronic lower back pain. Methods Human bone marrow mesenchymal stem cells (hBMMSCs) were isolated from fresh human anticoagulated whole bone marrow and were cultured side by side in atmospheric (20% O2) and hypoxic (5% O2) oxygen partial pressure for up to 3 passages. Stem cell fitness was assessed by clonogenic assay, cell surface marker expression and differentiation potential. Whole genome expression was performed by mRNA sequencing. Data from clonogenic assays, cell surface marker by flow cytometry and gene expression by quantitative PCR were analyzed by two-tailed paired Student’s t-test. Data from mRNA sequencing were aligned to hg19 using Tophat-2.0.13 and analyzed using Cufflinks-2.1.1. Results Hypoxic culturing of hBMMSCs had positive effects on cell fitness, as evidenced by an increased clonogenicity and improved differentiation potential towards adipocyte and chondrocyte lineages. No difference in osteoblast differentiation or in cell surface markers were observed. Only a small subset of genes (34) were identified by mRNA sequencing to be significantly dysregulated by hypoxia. When clustered by biological function, these genes were associated with chondrogenesis and cartilage metabolism, inflammation and immunomodulation, cellular survival, migration and proliferation, vasculogenesis and angiogenesis. Conclusions Hypoxic culturing positively impacted hBMMSCs fitness and transcriptome, potentially improving inherent properties of these cells that are critical for the development of successful cellular therapies. Hypoxic culturing should be considered for the in vitro expansion of hBMMSCs during manufacturing of cellular therapies targeting orthopedic disorders such as lower back pain.
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Affiliation(s)
- C Elabd
- BioRestorative Therapies, Inc., 40 Marcus Drive, Suite 1, Melville, NY, 11747, USA
| | - T E Ichim
- Immune Advisors, LLC, La Jolla, CA, 92037, USA
| | - K Miller
- BioRestorative Therapies, Inc., 40 Marcus Drive, Suite 1, Melville, NY, 11747, USA
| | - A Anneling
- BioRestorative Therapies, Inc., 40 Marcus Drive, Suite 1, Melville, NY, 11747, USA
| | - V Grinstein
- BioRestorative Therapies, Inc., 40 Marcus Drive, Suite 1, Melville, NY, 11747, USA
| | - V Vargas
- BioRestorative Therapies, Inc., 40 Marcus Drive, Suite 1, Melville, NY, 11747, USA
| | - F J Silva
- BioRestorative Therapies, Inc., 40 Marcus Drive, Suite 1, Melville, NY, 11747, USA.
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27
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Song N, Zhang T, Xu X, Lu Z, Yu X, Fang Y, Hu J, Jia P, Teng J, Ding X. miR-21 Protects Against Ischemia/Reperfusion-Induced Acute Kidney Injury by Preventing Epithelial Cell Apoptosis and Inhibiting Dendritic Cell Maturation. Front Physiol 2018; 9:790. [PMID: 30013485 PMCID: PMC6036242 DOI: 10.3389/fphys.2018.00790] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/06/2018] [Indexed: 02/02/2023] Open
Abstract
Renal tubular injury and innate immune responses induced by hypoxia contribute to acute kidney injury. Accumulating evidence suggests that miR-21 overexpression protects against kidney ischemia injury. Additionally, miR-21 emerges as a key inhibitor in dendritic cell maturation. Thus, we hypothesized that miR-21 protects the kidney from IR injury by suppressing epithelial cell damage and inflammatory reaction. In this study, we investigated effects of miR-21 and its signaling pathways (PTEN/AKT/mTOR/HIF, PDCD4/NFκ-B) on kidney ischemia/reperfusion (IR) injury in vitro and in vivo. The results revealed that IR increased miR-21, HIF1α, and 2α expression in vivo and in vitro. MiR-21 interacted with HIF1α and 2α through the PTEN/AKT/mTOR pathway. Moreover, inhibition of miR-21 activated PDCD4/NFκ-B pathways, which are critical for dendritic cell maturation. Renal IR triggers local inflammation by inducing the dendritic cell maturation and promoting the secretion of IL-12, IL-6, and TNF-α cytokines. Knockdown of miR-21 intensified the effect of IR on tubular epithelial cell apoptosis and dendritic cell maturation. Our results suggested that IR-inducible miR-21 protects epithelial cells from IR injury via a feedback interaction with HIF (PTEN/AKT/mTOR/HIF/miR-21) and by inhibiting maturation of DCs through the PDCD4/NF-κB pathway. These findings highlight new therapeutic opportunities in AKI.
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Affiliation(s)
- Nana Song
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Ting Zhang
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - XiaLian Xu
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Zhihui Lu
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Xiaofang Yu
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Yi Fang
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Jiachang Hu
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Ping Jia
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Jie Teng
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
| | - Xiaoqiang Ding
- Division of Nephrology, Zhongshan Hospital,Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Hemodialysis Quality Control Center of Shanghai, Shanghai, China
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28
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Persson PB, Bondke Persson A. Oxygen-to little, too much or just right. Acta Physiol (Oxf) 2018; 223:e13076. [PMID: 29675842 DOI: 10.1111/apha.13076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- P B Persson
- Charité - Universitätsmedizin Berlin - corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Vegetative Physiology, Berlin, Germany
| | - A Bondke Persson
- Charité - Universitätsmedizin Berlin - corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
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29
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Almohanna AM, Wray S. Hypoxic conditioning in blood vessels and smooth muscle tissues: effects on function, mechanisms, and unknowns. Am J Physiol Heart Circ Physiol 2018; 315:H756-H770. [PMID: 29702009 DOI: 10.1152/ajpheart.00725.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hypoxic preconditioning, the protective effect of brief, intermittent hypoxic or ischemic episodes on subsequent more severe hypoxic episodes, has been known for 30 yr from studies on cardiac muscle. The concept of hypoxic preconditioning has expanded; excitingly, organs beyond the heart, including the brain, liver, and kidney, also benefit. Preconditioning of vascular and visceral smooth muscles has received less attention despite their obvious importance to health. In addition, there has been no attempt to synthesize the literature in this field. Therefore, in addition to overviewing the current understanding of hypoxic conditioning, in the present review, we consider the role of blood vessels in conditioning and explore evidence for conditioning in other smooth muscles. Where possible, we have distinguished effects on myocytes from other cell types in the visceral organs. We found evidence of a pivotal role for blood vessels in conditioning and for conditioning in other smooth muscle, including the bladder, vascular myocytes, and gastrointestinal tract, and a novel response in the uterus of a hypoxic-induced force increase, which helps maintain contractions during labor. To date, however, there are insufficient data to provide a comprehensive or unifying mechanism for smooth muscles or visceral organs and the effects of conditioning on their function. This also means that no firm conclusions can be drawn as to how differences between smooth muscles in metabolic and contractile activity may contribute to conditioning. Therefore, we have suggested what may be general mechanisms of conditioning occurring in all smooth muscles and tabulated tissue-specific mechanistic findings and suggested ideas for further progress.
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Affiliation(s)
- Asmaa M Almohanna
- Department of Molecular and Cellular Physiology, Institute of Translational Medicine University of Liverpool , Liverpool , United Kingdom.,Princess Nourah bint Abdulrahman University , Riyadh , Saudi Arabia
| | - Susan Wray
- Department of Molecular and Cellular Physiology, Institute of Translational Medicine University of Liverpool , Liverpool , United Kingdom
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30
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Zhang Z, Payne K, Pallone TL. Adaptive responses of rat descending vasa recta to ischemia. Am J Physiol Renal Physiol 2018; 314:F373-F380. [PMID: 28814437 DOI: 10.1152/ajprenal.00062.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
tested whether rat descending vasa recta (DVR) undergo regulatory adaptations after the kidney is exposed to ischemia. Left kidneys (LK) were subjected to 30-min renal artery cross clamp. After 48 h, the postischemic LK and contralateral right kidney (RK) were harvested for study. When compared with DVR isolated from either sham-operated LK or the contralateral RK, postischemic LK DVR markedly increased their NO generation. The selective inducible NOS (iNOS) inhibitor 1400W blocked the NO response. Immunoblots from outer medullary homogenates showed a parallel 2.6-fold increase in iNOS expression ( P = 0.01). Microperfused postischemic LK DVR exposed to angiotensin II (ANG II, 10 nM), constricted less than those from the contralateral RK, and constricted more when exposed to 1400W (10 µM). Resting membrane potentials of pericytes from postischemic LK DVR pericytes were hyperpolarized relative to contralateral RK pericytes (62.0 ± 1.6 vs. 51.8 ± 2.2 mV, respectively, P < 0.05) or those from sham-operated LK (54.9 ± 2.1 mV, P < 0.05). Blockade of NO generation with 1400W did not repolarize postischemic pericytes (62.5 ± 1.4 vs. 61.1 ± 3.4 mV); however, control pericytes were hyperpolarized by exposure to NO donation from S-nitroso- N-acetyl- dl-penicillamine (51.5 ± 2.9 to 62.1 ± 1.4 mV, P < 0.05). We conclude that postischemic adaptations intrinsic to the DVR wall occur after ischemia. A rise in 1400W sensitive NO generation and iNOS expression occurs that is associated with diminished contractile responses to ANG II. Pericyte hyperpolarization occurs that is not explained by the rise in ambient NO generation within the DVR wall.
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Affiliation(s)
- Zhong Zhang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine , Baltimore, Maryland
| | - Kristie Payne
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine , Baltimore, Maryland
| | - Thomas L Pallone
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine , Baltimore, Maryland.,Baltimore Veterans Administration Medical Center , Baltimore, Maryland
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31
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Aguilar M, González-Candia A, Rodríguez J, Carrasco-Pozo C, Cañas D, García-Herrera C, Herrera EA, Castillo RL. Mechanisms of Cardiovascular Protection Associated with Intermittent Hypobaric Hypoxia Exposure in a Rat Model: Role of Oxidative Stress. Int J Mol Sci 2018; 19:ijms19020366. [PMID: 29373484 PMCID: PMC5855588 DOI: 10.3390/ijms19020366] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/08/2018] [Accepted: 01/09/2018] [Indexed: 12/25/2022] Open
Abstract
More than 140 million people live and works (in a chronic or intermittent form) above 2500 m worldwide and 35 million live in the Andean Mountains. Furthermore, in Chile, it is estimated that 55,000 persons work in high altitude shifts, where stays at lowlands and interspersed with working stays at highlands. Acute exposure to high altitude has been shown to induce oxidative stress in healthy human lowlanders, due to an increase in free radical formation and a decrease in antioxidant capacity. However, in animal models, intermittent hypoxia (IH) induce preconditioning, like responses and cardioprotection. Here, we aimed to describe in a rat model the responses on cardiac and vascular function to 4 cycles of intermittent hypobaric hypoxia (IHH). Twelve adult Wistar rats were randomly divided into two equal groups, a four-cycle of IHH, and a normobaric hypoxic control. Intermittent hypoxia was induced in a hypobaric chamber in four continuous cycles (1 cycle = 4 days hypoxia + 4 days normoxia), reaching a barometric pressure equivalent to 4600 m of altitude (428 Torr). At the end of the first and fourth cycle, cardiac structural, and functional variables were determined by echocardiography. Thereafter, ex vivo vascular function and biomechanical properties were determined in femoral arteries by wire myography. We further measured cardiac oxidative stress biomarkers (4-Hydroxy-nonenal, HNE; nytrotirosine, NT), reactive oxygen species (ROS) sources (NADPH and mitochondrial), and antioxidant enzymes activity (catalase, CAT; glutathione peroxidase, GPx, and superoxide dismutase, SOD). Our results show a higher ejection and shortening fraction of the left ventricle function by the end of the 4th cycle. Further, femoral vessels showed an improvement of vasodilator capacity and diminished stiffening. Cardiac tissue presented a higher expression of antioxidant enzymes and mitochondrial ROS formation in IHH, as compared with normobaric hypoxic controls. IHH exposure determines a preconditioning effect on the heart and femoral artery, both at structural and functional levels, associated with the induction of antioxidant defence mechanisms. However, mitochondrial ROS generation was increased in cardiac tissue. These findings suggest that initial states of IHH are beneficial for cardiovascular function and protection.
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Affiliation(s)
- Miguel Aguilar
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
| | - Alejandro González-Candia
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
| | - Jorge Rodríguez
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
- Departamento de Kinesiología, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
| | - Catalina Carrasco-Pozo
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD 4222, Australia.
- Departamento de Nutrición, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile.
| | - Daniel Cañas
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Santiago de Chile, Santiago 9170125, Chile.
| | - Claudio García-Herrera
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Santiago de Chile, Santiago 9170125, Chile.
| | - Emilio A Herrera
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
- International Center for Andean Studies, Universidad de Chile, Putre, Chile.
| | - Rodrigo L Castillo
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
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32
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Persson PB, Persson AB. Vitamin supplementation. Acta Physiol (Oxf) 2017; 219:537-539. [PMID: 28103422 DOI: 10.1111/apha.12850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- P B Persson
- Institute of Vegetative Physiology, Charité-Universitaetsmedizin Berlin, Berlin, Germany
| | - A B Persson
- Charité-Universitaetsmedizin Berlin, Berlin, Germany
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33
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Bickler PE, Feiner JR, Lipnick MS, Batchelder P, MacLeod DB, Severinghaus JW. Effects of Acute, Profound Hypoxia on Healthy Humans. Anesth Analg 2017; 124:146-153. [DOI: 10.1213/ane.0000000000001421] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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34
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Hillmeister P, Buschmann E, Persson PB, Bondke Persson A. Exercise for healthy flow. Acta Physiol (Oxf) 2017; 219:3-8. [PMID: 27863044 DOI: 10.1111/apha.12831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- P. Hillmeister
- Department for Angiology; Center for Internal Medicine I; Clinic Brandenburg, Medical University Brandenburg (MHB); Brandenburg an der Havel Germany
- Charité-Universitaetsmedizin Berlin; Berlin Germany
| | - E. Buschmann
- Department for Angiology; Center for Internal Medicine I; Clinic Brandenburg, Medical University Brandenburg (MHB); Brandenburg an der Havel Germany
- Charité-Universitaetsmedizin Berlin; Berlin Germany
| | - P. B. Persson
- Institute of Vegetative Physiology; Charité-Universitaetsmedizin Berlin; Berlin Germany
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Cardioprotection by remote ischemic conditioning and its signal transduction. Pflugers Arch 2016; 469:159-181. [DOI: 10.1007/s00424-016-1922-6] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 11/28/2016] [Indexed: 12/23/2022]
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Nekoui A, Blaise G. Erythropoietin and Nonhematopoietic Effects. Am J Med Sci 2016; 353:76-81. [PMID: 28104107 DOI: 10.1016/j.amjms.2016.10.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 10/21/2016] [Accepted: 10/27/2016] [Indexed: 01/21/2023]
Abstract
Erythropoietin (EPO) is the main regulator of red blood cell production. Since the 1990s, EPO has been used for the treatment of anemia associated with end-stage renal failure and chemotherapy. The erythropoietin receptors were found on other organs such as the brain, spinal cord, heart and skin. In addition, it has been shown that many tissues produce and locally release EPO in response to hypoxic, biochemical and physical stress. In cellular, animal and clinical studies, EPO protects tissues from ischemia and reperfusion injury, has antiapoptotic effects and improves regeneration after injury. In this article, we mainly review the nonhematopoietic effects and new possible clinical indications for EPO.
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Affiliation(s)
| | - Gilbert Blaise
- Department of Anesthesiology, Faculty of Medicine, Universite de Montreal, Quebec, Canada
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Epps JA, Smart NA. Remote ischaemic conditioning in the context of type 2 diabetes and neuropathy: the case for repeat application as a novel therapy for lower extremity ulceration. Cardiovasc Diabetol 2016; 15:130. [PMID: 27613524 PMCID: PMC5018170 DOI: 10.1186/s12933-016-0444-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 08/19/2016] [Indexed: 02/07/2023] Open
Abstract
An emerging treatment modality for reducing damage caused by ischaemia–reperfusion injury is ischaemic conditioning. This technique induces short periods of ischaemia that have been found to protect against a more significant ischaemic insult. Remote ischaemic conditioning (RIC) can be administered more conveniently and safely, by inflation of a pneumatic blood pressure cuff to a suprasystolic pressure on a limb. Protection is then transferred to a remote organ via humoral and neural pathways. The diabetic state is particularly vulnerable to ischaemia–reperfusion injury, and ischaemia is a significant cause of many diabetic complications, including the diabetic foot. Despite this, studies utilising ischaemic conditioning and RIC in type 2 diabetes have often been disappointing. A newer strategy, repeat RIC, involves the repeated application of short periods of limb ischaemia over days or weeks. It has been demonstrated that this improves endothelial function, skin microcirculation, and modulates the systemic inflammatory response. Repeat RIC was recently shown to be beneficial for healing in lower extremity diabetic ulcers. This article summarises the mechanisms of RIC, and the impact that type 2 diabetes may have upon these, with the role of neural mechanisms in the context of diabetic neuropathy a focus. Repeat RIC may show more promise than RIC in type 2 diabetes, and its potential mechanisms and applications will also be explored. Considering the high costs, rates of chronicity and serious complications resulting from diabetic lower extremity ulceration, repeat RIC has the potential to be an effective novel advanced therapy for this condition.
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Affiliation(s)
- J A Epps
- School of Science and Technology, The University of New England, Armidale, NSW, 2351, Australia
| | - N A Smart
- School of Science and Technology, The University of New England, Armidale, NSW, 2351, Australia.
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