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Chin K, Jiang H, Steinberg BE, Goldenberg NM, Desjardins JF, Kabir G, Liu E, Vanama R, Baker AJ, Deschamps A, Simpson JA, Maynes JT, Vinogradov SA, Connelly KA, Mazer CD, Hare GMT. Bilateral nephrectomy impairs cardiovascular function and cerebral perfusion in a rat model of acute hemodilutional anemia. J Appl Physiol (1985) 2024; 136:1245-1259. [PMID: 38385183 DOI: 10.1152/japplphysiol.00858.2023] [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: 11/28/2023] [Revised: 01/30/2024] [Accepted: 02/15/2024] [Indexed: 02/23/2024] Open
Abstract
Anemia and renal failure are independent risk factors for perioperative stroke, prompting us to assess the combined impact of acute hemodilutional anemia and bilateral nephrectomy (2Nx) on microvascular brain Po2 (PBro2) in a rat model. Changes in PBro2 (phosphorescence quenching) and cardiac output (CO, echocardiography) were measured in different groups of anesthetized Sprague-Dawley rats (1.5% isoflurane, n = 5-8/group) randomized to Sham 2Nx or 2Nx and subsequently exposed to acute hemodilutional anemia (50% estimated blood volume exchange with 6% hydroxyethyl starch) or time-based controls (no hemodilution). Outcomes were assessed by ANOVA with significance assigned at P < 0.05. At baseline, 2Nx rats demonstrated reduced CO (49.9 ± 9.4 vs. 66.3 ± 19.3 mL/min; P = 0.014) and PBro2 (21.1 ± 2.9 vs. 32.4 ± 3.1 mmHg; P < 0.001) relative to Sham 2Nx rats. Following hemodilution, 2Nx rats demonstrated a further decrease in PBro2 (15.0 ± 6.3 mmHg, P = 0.022). Hemodiluted 2Nx rats did not demonstrate a comparable increase in CO after hemodilution compared with Sham 2Nx (74.8 ± 22.4 vs. 108.9 ± 18.8 mL/min, P = 0.003) that likely contributed to the observed reduction in PBro2. This impaired CO response was associated with reduced fractional shortening (33 ± 9 vs. 51 ± 5%) and increased left ventricular end-systolic volume (156 ± 51 vs. 72 ± 15 µL, P < 0.001) suggestive of systolic dysfunction. By contrast, hemodiluted Sham 2Nx animals demonstrated a robust increase in CO and preserved PBro2. These data support the hypothesis that the kidney plays a central role in maintaining cerebral perfusion and initiating the adaptive increase in CO required to optimize PBro2 during acute anemia.NEW & NOTEWORTHY This study has demonstrated that bilateral nephrectomy acutely impaired cardiac output (CO) and microvascular brain Po2 (PBro2), at baseline. Following acute hemodilution, nephrectomy prevented the adaptive increase in CO associated with acute hemodilution leading to a further reduction in PBro2, accentuating the degree of cerebral tissue hypoxia. These data support a role for the kidney in maintaining PBro2 and initiating the increase in CO that optimized brain perfusion during acute anemia.
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Affiliation(s)
- Kyle Chin
- Department of Anesthesiology and Pain Medicine, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Helen Jiang
- Department of Anesthesiology and Pain Medicine, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Benjamin E Steinberg
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, The University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Neil M Goldenberg
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, The University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Jean-Francois Desjardins
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Cardiology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Golam Kabir
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Cardiology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Elaine Liu
- Department of Anesthesiology and Pain Medicine, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Ramesh Vanama
- Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, The University of Toronto, Toronto, Ontario, Canada
| | - Andrew J Baker
- Department of Anesthesiology and Pain Medicine, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Alain Deschamps
- Institut de Cardiologie de Montréal, Université de Montréal, Montreal Quebec, Canada
| | - Jeremy A Simpson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
- IMPART investigator team Canada (https://impart.team/), Saint John, New Brunswick, Canada
| | - Jason T Maynes
- Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, The University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada
- Program in Molecular Medicine, Hospital for Sick Children's Research Institute, Toronto, Ontario, Canada
| | - Sergei A Vinogradov
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Kim A Connelly
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Division of Cardiology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - C David Mazer
- Department of Anesthesiology and Pain Medicine, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Gregory M T Hare
- Department of Anesthesiology and Pain Medicine, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
- IMPART investigator team Canada (https://impart.team/), Saint John, New Brunswick, Canada
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Hencz A, Magony A, Thomas C, Kovacs K, Szilagyi G, Pal J, Sik A. Mild hypoxia-induced structural and functional changes of the hippocampal network. Front Cell Neurosci 2023; 17:1277375. [PMID: 37841285 PMCID: PMC10576450 DOI: 10.3389/fncel.2023.1277375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/15/2023] [Indexed: 10/17/2023] Open
Abstract
Hypoxia causes structural and functional changes in several brain regions, including the oxygen-concentration-sensitive hippocampus. We investigated the consequences of mild short-term hypoxia on rat hippocampus in vivo. The hypoxic group was treated with 16% O2 for 1 h, and the control group with 21% O2. Using a combination of Gallyas silver impregnation histochemistry revealing damaged neurons and interneuron-specific immunohistochemistry, we found that somatostatin-expressing inhibitory neurons in the hilus were injured. We used 32-channel silicon probe arrays to record network oscillations and unit activity from the hippocampal layers under anaesthesia. There were no changes in the frequency power of slow, theta, beta, or gamma bands, but we found a significant increase in the frequency of slow oscillation (2.1-2.2 Hz) at 16% O2 compared to 21% O2. In the hilus region, the firing frequency of unidentified interneurons decreased. In the CA3 region, the firing frequency of some unidentified interneurons decreased while the activity of other interneurons increased. The activity of pyramidal cells increased both in the CA1 and CA3 regions. In addition, the regularity of CA1, CA3 pyramidal cells' and CA3 type II and hilar interneuron activity has significantly changed in hypoxic conditions. In summary, a low O2 environment caused profound changes in the state of hippocampal excitatory and inhibitory neurons and network activity, indicating potential changes in information processing caused by mild short-term hypoxia.
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Affiliation(s)
- Alexandra Hencz
- Institute of Physiology, Medical School, University of Pecs, Pecs, Hungary
| | - Andor Magony
- Institute of Physiology, Medical School, University of Pecs, Pecs, Hungary
- Institute of Transdisciplinary Discoveries, Medical School, University of Pecs, Pecs, Hungary
| | - Chloe Thomas
- Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Krisztina Kovacs
- Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Gabor Szilagyi
- Institute of Biochemistry and Medical Chemistry, Medical School, University of Pecs, Pecs, Hungary
| | - Jozsef Pal
- Institute of Physiology, Medical School, University of Pecs, Pecs, Hungary
| | - Attila Sik
- Institute of Physiology, Medical School, University of Pecs, Pecs, Hungary
- Institute of Transdisciplinary Discoveries, Medical School, University of Pecs, Pecs, Hungary
- Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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3
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Mistry N, Hare GM, Shehata N, Kramer RS, Fawzy HF, Baker RA, Carmona P, Saczkowski R, Filipescu D, Alphonsus CS, Rochon A, Gregory AJ, Khanykin B, Leff JD, Mateo E, Karangelis D, Tellez JC, Saha T, Ko DT, Wijeysundera DN, Verma S, Mazer CD. Methemoglobin as a marker of acute anemic stress in cardiac surgery. iScience 2023; 26:107429. [PMID: 37575193 PMCID: PMC10415918 DOI: 10.1016/j.isci.2023.107429] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 05/01/2023] [Accepted: 07/17/2023] [Indexed: 08/15/2023] Open
Abstract
Biological evidence supports plasma methemoglobin as a biomarker for anemia-induced tissue hypoxia. In this translational planned substudy of the multinational randomized controlled transfusion thresholds in cardiac surgery (TRICS-III) trial, which included adults undergoing cardiac surgery requiring cardiopulmonary bypass with a moderate-to-high risk of death, we investigated the relationship between perioperative hemoglobin concentration (Hb) and methemoglobin; and evaluated its association with postoperative outcomes. The primary endpoint was a composite of death, myocardial infarction, stroke, and severe acute kidney injury at 28 days. We observe weak non-linear associations between decreasing Hb and increasing methemoglobin, which were strongest in magnitude at the post-surgical time point. Increased levels of post-surgical methemoglobin were associated with a trend toward an elevated risk for stroke and exploratory neurological outcomes. Our generalizable study demonstrates post-surgical methemoglobin may be a marker of anemia-induced organ injury/dysfunction, and may have utility for guiding personalized approaches to anemia management. Clinicaltrials.gov registration NCT02042898.
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Affiliation(s)
- Nikhil Mistry
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
| | - Gregory M.T. Hare
- Department of Anesthesia, St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Li Ka Shing Knowledge Institute of St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
| | - Nadine Shehata
- Division of Hematology, Sinai Health System, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Robert S. Kramer
- Maine Medical Center Cardiovascular Institute, Portland, ME, USA
| | - Hosam F. Fawzy
- Department of Cardiothoracic Surgery, Faculty of Medicine, University of Tanta, Tanta, Egypt
| | - Robert A. Baker
- Cardiac Surgery Research and Perfusion, Flinders University and Flinders Medical Centre, Adelaide, SA, Australia
| | - Paula Carmona
- Cardiovascular-Anesthesia and Intensive Care. University Hospital La Fe, Valencia, Spain
| | - Richard Saczkowski
- Department of Cardiac Sciences, Perfusion Services, Kelowna General Hospital, Kelowna, BC, Canada
| | - Daniela Filipescu
- University of Medicine and Pharmacy Carol Davila, Emergency Institute for Cardiovascular Diseases “Prof. Dr. C.C. Iliescu”, Bucharest, Romania
| | - Christella S. Alphonsus
- Department of Anaesthesia and Perioperative Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
| | | | - Alexander J. Gregory
- Department of Anesthesiology, Perioperative and Pain Medicine and Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Boris Khanykin
- Cardiothoracic Anesthesiology Department, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Jonathan D. Leff
- Montefiore-Einstein Center for Heart and Vascular Care, New York City, NY, USA
| | - Eva Mateo
- Hospital General Universitario de València, València, Spain
| | - Dimos Karangelis
- Department of Cardiothoracic Surgery, Democritus University of Thrace, Alexandroupolis, Greece
| | | | - Tarit Saha
- Department of Anesthesiology and Perioperative Medicine, Kingston General Hospital, Kingston, ON, Canada
| | - Dennis T. Ko
- Schulich Heart Program, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
- Institute of Health Policy Management, and Evaluation, University of Toronto, Toronto, ON, Canada
- ICES, Toronto, ON, Canada
| | - Duminda N. Wijeysundera
- Department of Anesthesia, St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada
- Li Ka Shing Knowledge Institute of St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
- Institute of Health Policy Management, and Evaluation, University of Toronto, Toronto, ON, Canada
- ICES, Toronto, ON, Canada
| | - Subodh Verma
- Li Ka Shing Knowledge Institute of St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
- Division of Cardiac Surgery, St. Michael’s Hospital, Department of Surgery, University of Toronto, Toronto, ON, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - C. David Mazer
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia, St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Li Ka Shing Knowledge Institute of St. Michael’s Hospital, Unity Health Toronto, Toronto, ON, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
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Chin K, Joo H, Jiang H, Lin C, Savinova I, Joo S, Alli A, Sklar MC, Papa F, Simpson J, Baker AJ, Mazer CD, Darrah W, Hare GMT. Importance of assessing biomarkers and physiological parameters of anemia-induced tissue hypoxia in the perioperative period. BRAZILIAN JOURNAL OF ANESTHESIOLOGY (ELSEVIER) 2023; 73:186-197. [PMID: 36377057 PMCID: PMC10068554 DOI: 10.1016/j.bjane.2022.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022]
Abstract
Anemia is associated with increased risk of Acute Kidney Injury (AKI), stroke and mortality in perioperative patients. We sought to understand the mechanism(s) by assessing the integrative physiological responses to anemia (kidney, brain), the degrees of anemia-induced tissue hypoxia, and associated biomarkers and physiological parameters. Experimental measurements demonstrate a linear relationship between blood Oxygen Content (CaO2) and renal microvascular PO2 (y = 0.30x + 6.9, r2 = 0.75), demonstrating that renal hypoxia is proportional to the degree of anemia. This defines the kidney as a potential oxygen sensor during anemia. Further evidence of renal oxygen sensing is demonstrated by proportional increase in serum Erythropoietin (EPO) during anemia (y = 93.806*10-0.02, r2 = 0.82). This data implicates systemic EPO levels as a biomarker of anemia-induced renal tissue hypoxia. By contrast, cerebral Oxygen Delivery (DO2) is defended by a profound proportional increase in Cerebral Blood Flow (CBF), minimizing tissue hypoxia in the brain, until more severe levels of anemia occur. We hypothesize that the kidney experiences profound early anemia-induced tissue hypoxia which contributes to adaptive mechanisms to preserve cerebral perfusion. At severe levels of anemia, renal hypoxia intensifies, and cerebral hypoxia occurs, possibly contributing to the mechanism(s) of AKI and stroke when adaptive mechanisms to preserve organ perfusion are overwhelmed. Clinical methods to detect renal tissue hypoxia (an early warning signal) and cerebral hypoxia (a later consequence of severe anemia) may inform clinical practice and support the assessment of clinical biomarkers (i.e., EPO) and physiological parameters (i.e., urinary PO2) of anemia-induced tissue hypoxia. This information may direct targeted treatment strategies to prevent adverse outcomes associated with anemia.
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Affiliation(s)
- Kyle Chin
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; University of Toronto, Department of Physiology, Toronto, Canada
| | - Hannah Joo
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Helen Jiang
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Chloe Lin
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Iryna Savinova
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Canada
| | - Sarah Joo
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Ahmad Alli
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Michael C Sklar
- St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; University of Toronto, Temerty Faculty of Medicine, Interdepartmental Division of Critical Care Medicine, Toronto, Canada; University of Toronto, St. Michael's Hospital, Department of Critical Care, Toronto, Canada
| | - Fabio Papa
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Jeremy Simpson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Canada
| | - Andrew J Baker
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; University of Toronto, Temerty Faculty of Medicine, Interdepartmental Division of Critical Care Medicine, Toronto, Canada; University of Toronto, St. Michael's Hospital, Department of Critical Care, Toronto, Canada
| | - C David Mazer
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; University of Toronto, Department of Physiology, Toronto, Canada; St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; University of Toronto, Temerty Faculty of Medicine, Interdepartmental Division of Critical Care Medicine, Toronto, Canada; University of Toronto, St. Michael's Hospital, Department of Critical Care, Toronto, Canada
| | - William Darrah
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Gregory M T Hare
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; University of Toronto, Department of Physiology, Toronto, Canada; St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; St. Michael's Hospital Center of Excellence for Patient Blood Management, 30 Bond Street, Toronto, Canada.
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5
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González-Zacarías C, Choi S, Vu C, Xu B, Shen J, Joshi AA, Leahy RM, Wood JC. Chronic anemia: The effects on the connectivity of white matter. Front Neurol 2022; 13:894742. [PMID: 35959402 PMCID: PMC9362738 DOI: 10.3389/fneur.2022.894742] [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: 03/12/2022] [Accepted: 06/29/2022] [Indexed: 01/26/2023] Open
Abstract
Chronic anemia is commonly observed in patients with hemoglobinopathies, mainly represented by disorders of altered hemoglobin (Hb) structure (sickle cell disease, SCD) and impaired Hb synthesis (e.g. thalassemia syndromes, non-SCD anemia). Both hemoglobinopathies have been associated with white matter (WM) alterations. Novel structural MRI research in our laboratory demonstrated that WM volume was diffusely lower in deep, watershed areas proportional to anemia severity. Furthermore, diffusion tensor imaging analysis has provided evidence that WM microstructure is disrupted proportionally to Hb level and oxygen saturation. SCD patients have been widely studied and demonstrate lower fractional anisotropy (FA) in the corticospinal tract and cerebellum across the internal capsule and corpus callosum. In the present study, we compared 19 SCD and 15 non-SCD anemia patients with a wide range of Hb values allowing the characterization of the effects of chronic anemia in isolation of sickle Hb. We performed a tensor analysis to quantify FA changes in WM connectivity in chronic anemic patients. We calculated the volumetric mean of FA along the pathway of tracks connecting two regions of interest defined by BrainSuite's BCI-DNI atlas. In general, we found lower FA values in anemic patients; indicating the loss of coherence in the main diffusion direction that potentially indicates WM injury. We saw a positive correlation between FA and hemoglobin in these same regions, suggesting that decreased WM microstructural integrity FA is highly driven by chronic hypoxia. The only connection that did not follow this pattern was the connectivity within the left middle-inferior temporal gyrus. Interestingly, more reductions in FA were observed in non-SCD patients (mainly along with intrahemispheric WM bundles and watershed areas) than the SCD patients (mainly interhemispheric).
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Affiliation(s)
- Clio González-Zacarías
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, United States,Signal and Image Processing Institute, University of Southern California, Los Angeles, CA, United States,Department of Pediatrics and Radiology, Children's Hospital Los Angeles, Los Angeles, CA, United States
| | - Soyoung Choi
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, United States,Signal and Image Processing Institute, University of Southern California, Los Angeles, CA, United States,Department of Pediatrics and Radiology, Children's Hospital Los Angeles, Los Angeles, CA, United States
| | - Chau Vu
- Department of Pediatrics and Radiology, Children's Hospital Los Angeles, Los Angeles, CA, United States,Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Botian Xu
- Department of Pediatrics and Radiology, Children's Hospital Los Angeles, Los Angeles, CA, United States,Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Jian Shen
- Department of Pediatrics and Radiology, Children's Hospital Los Angeles, Los Angeles, CA, United States,Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Anand A. Joshi
- Signal and Image Processing Institute, University of Southern California, Los Angeles, CA, United States
| | - Richard M. Leahy
- Signal and Image Processing Institute, University of Southern California, Los Angeles, CA, United States,Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - John C. Wood
- Department of Pediatrics and Radiology, Children's Hospital Los Angeles, Los Angeles, CA, United States,Biomedical Engineering, University of Southern California, Los Angeles, CA, United States,*Correspondence: John C. Wood
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6
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Enhanced oxidative phosphorylation of IgG plasma cells can contribute to hypoxia in the mucosa of active ulcerative colitis. Histochem Cell Biol 2022; 158:335-344. [PMID: 35716204 DOI: 10.1007/s00418-022-02122-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 11/04/2022]
Abstract
Mucosal hypoxia is detected in the mucosa of ulcerative colitis (UC), however the mechanism and the cause of hypoxia is not fully understood, while a dense infiltration of plasma cells is observed in the inflamed mucosa of UC. When differentiating from a B cell to a plasma cell, the energy metabolism dramatically shifts from glycolysis to oxidative phosphorylation, which results in a large amount of oxygen consumption of the plasma cell. We hypothesized that the plasma cell infiltration into the inflamed mucosa contributes to the mucosal hypoxia in UC in part. We examined the association between mucosal hypoxia and plasma cell infiltration in UC. More IgG plasma cells (but not IgA plasma cells) were distributed, and the nuclear and cell sizes were enlarged in hypoxic mucosa compared to normoxic mucosa in UC. Oxidative phosphorylation signature genes of these IgG plasma cells were markedly upregulated compared to those of other lymphoid cells infiltrating the lamina propria of inflamed mucosa of UC. Enlarged IgG plasma cells, which increase in number in the inflamed mucosa of UC, can be related to the hypoxic state of the inflamed mucosa of UC.
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7
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Li QY, Liu F, Tang X, Fu H, Mao J. Renoprotective Role of Hypoxia-Inducible Factors and the Mechanism. KIDNEY DISEASES (BASEL, SWITZERLAND) 2022; 8:44-56. [PMID: 35224006 PMCID: PMC8820168 DOI: 10.1159/000520141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 10/09/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND The kidney requires abundant blood supply, and oxygen is transmitted by diffusion through blood vessels. Most physiological metabolism of the kidney depends on oxygen, so it is very sensitive to oxygen. An increasing pool of evidence suggests that hypoxia is involved in almost all acute and chronic kidney diseases (CKDs). Vascular damage, tubular injury, and fibrosis are the main pathologies associated during hypoxia. Hypoxia-inducible factors (HIFs) are the main mediators during hypoxia, but their functions remain controversial. This article reviewed recent studies and described its mechanisms on renoprotection. SUMMARY HIF is degraded rapidly during under normal oxygen. But under hypoxia, HIFs accumulate and many target genes are regulated by HIFs. Homeostasis during injury is maintained through these genes. Pretreatment of HIF can protect the kidney from acute hypoxia and can improve repair, but HIF's role in CKD and in renal tumor is still controversial. Due to its mechanism in kidney disease, many drugs toward HIFs are widely researched, even some of which have been used in clinical or in clinical research. KEY MESSAGES In this review, we described the known physiological mechanisms, target genes, and renal protective roles of HIFs, and we discussed several drugs that are researched due to such renal protective roles.
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9
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Lankadeva YR, May CN, Cochrane AD, Marino B, Hood SG, McCall PR, Okazaki N, Bellomo R, Evans RG. Influence of blood haemoglobin concentration on renal haemodynamics and oxygenation during experimental cardiopulmonary bypass in sheep. Acta Physiol (Oxf) 2021; 231:e13583. [PMID: 33222404 DOI: 10.1111/apha.13583] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/28/2020] [Accepted: 11/17/2020] [Indexed: 12/29/2022]
Abstract
AIM Blood transfusion may improve renal oxygenation during cardiopulmonary bypass (CPB). In an ovine model of experimental CPB, we tested whether increasing blood haemoglobin concentration [Hb] from ~7 g dL-1 to ~9 g dL-1 improves renal tissue oxygenation. METHODS Ten sheep were studied while conscious, under stable isoflurane anaesthesia, and during 3 hours of CPB. In a randomized cross-over design, 5 sheep commenced bypass at a high target [Hb], achieved by adding 600 mL donor blood to the priming solution. After 90 minutes of CPB, PlasmaLyte® was added to the blood reservoir to achieve low target [Hb]. For the other 5 sheep, no blood was added to the prime, but after 90 minutes of CPB, 800-900 mL of donor blood was given to achieve a high target [Hb]. RESULTS Overall, CPB was associated with marked reductions in renal oxygen delivery (-50 ± 12%, mean ± 95% confidence interval) and medullary tissue oxygen tension (PO2 , -54 ± 29%). Renal fractional oxygen extraction was 17 ± 10% less during CPB at high [Hb] than low [Hb] (P = .04). Nevertheless, no increase in tissue PO2 in either the renal medulla (0 ± 6 mmHg change, P > .99) or cortex (-19 ± 13 mmHg change, P = .08) was detected with high [Hb]. CONCLUSIONS In experimental CPB blood transfusion to increase Hb concentration from ~7 g dL-1 to ~9 g dL-1 did not improve renal cortical or medullary tissue PO2 even though it decreased whole kidney oxygen extraction.
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Affiliation(s)
- Yugeesh R Lankadeva
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
- Centre for Integrated Critical Care, Department of Medicine and Radiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Clive N May
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
- Centre for Integrated Critical Care, Department of Medicine and Radiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Andrew D Cochrane
- Department of Cardiothoracic Surgery, Monash Health and Department of Surgery (School of Clinical Sciences at Monash Health), Monash University, Melbourne, VIC, Australia
| | - Bruno Marino
- Cellsaving and Perfusion Resources, Melbourne, VIC, Australia
| | - Sally G Hood
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
| | - Peter R McCall
- Department of Anaesthesia, Austin Health, Heidelberg, VIC, Australia
| | - Nobuki Okazaki
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
- Department of Anesthesiology and Resuscitology, Okayama University, Okayama, Japan
| | - Rinaldo Bellomo
- Centre for Integrated Critical Care, Department of Medicine and Radiology, The University of Melbourne, Melbourne, VIC, Australia
- Department of Intensive Care, Austin Health, Heidelberg, VIC, Australia
| | - Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
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10
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Chin K, Cazorla-Bak MP, Liu E, Nghiem L, Zhang Y, Yu J, Wilson DF, Vinogradov SA, Gilbert RE, Connelly KA, Evans RG, Baker AJ, David Mazer C, Hare GMT. Renal microvascular oxygen tension during hyperoxia and acute hemodilution assessed by phosphorescence quenching and excitation with blue and red light. Can J Anaesth 2020; 68:214-225. [PMID: 33174162 DOI: 10.1007/s12630-020-01848-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/05/2020] [Accepted: 08/14/2020] [Indexed: 12/13/2022] Open
Abstract
PURPOSE The kidney plays a central physiologic role as an oxygen sensor. Nevertheless, the direct mechanism by which this occurs is incompletely understood. We measured renal microvascular partial pressure of oxygen (PkO2) to determine the impact of clinically relevant conditions that acutely change PkO2 including hyperoxia and hemodilution. METHODS We utilized two-wavelength excitation (red and blue spectrum) of the intravascular phosphorescent oxygen sensitive probe Oxyphor PdG4 to measure renal tissue PO2 in anesthetized rats (2% isoflurane, n = 6) under two conditions of altered arterial blood oxygen content (CaO2): 1) hyperoxia (fractional inspired oxygen 21%, 30%, and 50%) and 2) acute hemodilutional anemia (baseline, 25% and 50% acute hemodilution). The mean arterial blood pressure (MAP), rectal temperature, arterial blood gases (ABGs), and chemistry (radiometer) were measured under each condition. Blue and red light enabled measurement of PkO2 in the superficial renal cortex and deeper cortical and medullary tissue, respectively. RESULTS PkO2 was higher in the superficial renal cortex (~ 60 mmHg, blue light) relative to the deeper renal cortex and outer medulla (~ 45 mmHg, red light). Hyperoxia resulted in a proportional increase in PkO2 values while hemodilution decreased microvascular PkO2 in a linear manner in both superficial and deeper regions of the kidney. In both cases (blue and red light), PkO2 correlated with CaO2 but not with MAP. CONCLUSION The observed linear relationship between CaO2 and PkO2 shows the biological function of the kidney as a quantitative sensor of anemic hypoxia and hyperoxia. A better understanding of the impact of changes in PkO2 may inform clinical practices to improve renal oxygen delivery and prevent acute kidney injury.
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Affiliation(s)
- Kyle Chin
- Department of Anesthesia, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada
| | - Melina P Cazorla-Bak
- Department of Anesthesia, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Elaine Liu
- Department of Anesthesia, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada
| | - Linda Nghiem
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | - Yanling Zhang
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | - Julie Yu
- Deaprtment of Anesthesia and Perioperative Medicine, Western University, London, ON, Canada
| | - David F Wilson
- Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sergei A Vinogradov
- Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Richard E Gilbert
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada.,Division of Endocrinology, Department of Medicine, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada
| | - Kim A Connelly
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada.,Division of Cardiology, Department of Medicine, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada
| | - Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Andrew J Baker
- Department of Anesthesia, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada.,Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - C David Mazer
- Department of Anesthesia, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Gregory M T Hare
- Department of Anesthesia, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. .,Department of Physiology, University of Toronto, Toronto, ON, Canada. .,Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada.
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11
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The Effect of MicroRNA-101 on Angiogenesis of Human Umbilical Vein Endothelial Cells during Hypoxia and in Mice with Myocardial Infarction. BIOMED RESEARCH INTERNATIONAL 2020; 2020:5426971. [PMID: 32953883 PMCID: PMC7487113 DOI: 10.1155/2020/5426971] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/10/2020] [Accepted: 08/05/2020] [Indexed: 12/15/2022]
Abstract
Background Previous studies showed that recanalization and angiogenesis within the infarct region are of vital importance to the survival of myocardial cells during the treatment of acute myocardial infarction (AMI). Methods In this study, EdU cell proliferation assay, Transwell assay, scratch wound assay, and tube formation assay were used. Twelve bioinformatics analysis packages were used to predict the target genes of miR-101. Target genes were verified by luciferase reporter generation and assay, fluorescent quantitative PCR, and western blotting. Animal model and treatments were detected by M-mode echocardiography and immunofluorescent staining of CD31, Ki67, and α-SMA. Results AgomiR-101 significantly enhanced HUVEC proliferation, migration, and tube formation. A double-luciferase reporter assay revealed that the hsa-miR-101 mimic attenuated the activity of the EIF4E3′-UTR-wt type plasmid by 36%. The expression levels of HIF-1α and VEGF-A in the scrambled RNA group were significantly lower than those in the EIF4E3 siRNA and agomiR-101 groups. The left ventricular ejection fraction of the AMI+Adv-miR-101 group was significantly higher than that of the AMI+Adv-null and Sham+Adv-null groups. The proliferation of vessel cells in the peripheral infarcted myocardium was higher in the AMI+Adv-miR-101 group than that in the AMI+Adv-null and Sham+Adv-null groups. Conclusion MiR-101 can promote angiogenesis in the region surrounding the myocardial infarction.
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12
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When to transfuse your acute care patient? A narrative review of the risk of anemia and red blood cell transfusion based on clinical trial outcomes. Can J Anaesth 2020; 67:1576-1594. [DOI: 10.1007/s12630-020-01763-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/07/2020] [Accepted: 05/07/2020] [Indexed: 12/14/2022] Open
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13
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Abrahamson JR, Read A, Chin K, Mistry N, Joo H, Desjardins JF, Liu E, Thai K, Wilson DF, Vinogradov SA, Maynes JT, Gilbert RE, Connelly KA, Baker AJ, Mazer CD, Hare GMT. Renal tissue Po2sensing during acute hemodilution is dependent on the diluent. Am J Physiol Regul Integr Comp Physiol 2020; 318:R799-R812. [DOI: 10.1152/ajpregu.00323.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Sensing changes in blood oxygen content ([Formula: see text]) is an important physiological role of the kidney; however, the mechanism(s) by which the kidneys sense and respond to changes in [Formula: see text] are incompletely understood. Accurate measurements of kidney tissue oxygen tension ([Formula: see text]) may increase our understanding of renal oxygen-sensing mechanisms and could inform decisions regarding the optimal fluid for intravascular volume resuscitation to maintain renal perfusion. In some clinical settings, starch solution may be nephrotoxic, possibly due to inadequacy of tissue oxygen delivery. We hypothesized that hemodilution with starch colloid solutions would reduce [Formula: see text] to a more severe degree than other diluents. Anesthetized Sprague-Dawley rats ( n = 77) were randomized to undergo hemodilution with either colloid (6% hydroxyethyl starch or 5% albumin), crystalloid (0.9% saline), or a sham procedure (control) ( n = 13–18 rats/group). Data were analyzed by ANOVA with significance assigned at P < 0.05. After hemodilution, mean arterial pressure (MAP) decreased marginally in all groups, while hemoglobin (Hb) and [Formula: see text] decreased in proportion to the degree of hemodilution. Cardiac output was maintained in all groups after hemodilution. [Formula: see text] decreased in proportion to the reduction in Hb in all treatment groups. At comparably reduced Hb, and maintained arterial oxygen values, hemodilution with starch resulted in larger decreases in [Formula: see text] relative to animals hemodiluted with albumin or saline ( P < 0.008). Renal medullary erythropoietin (EPO) mRNA levels increased more prominently, relative to other hypoxia-regulated molecules (GLUT-1, GAPDH, and VEGF). Our data demonstrate that the kidney acts as a biosensor of reduced [Formula: see text] following hemodilution and that [Formula: see text] may provide a quantitative signal for renal cellular responsiveness to acute anemia. Evidence of a more severe reduction in [Formula: see text] following hemodilution with starch colloid solution suggests that tissue hypoxia may contribute to starch induced renal toxicity.
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Affiliation(s)
- Jessica R. Abrahamson
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Austin Read
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Kyle Chin
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Nikhil Mistry
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Ontario, Canada
| | - Hannah Joo
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Jean-Francois Desjardins
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
| | - Elaine Liu
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Kerri Thai
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
| | - David F. Wilson
- Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Sergei A. Vinogradov
- Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jason T. Maynes
- Department of Anesthesia and Pain Medicine, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Richard E. Gilbert
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
- Department of Medicine, Division of Endocrinology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Kim A. Connelly
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
- Department of Medicine, Division of Cardiology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Andrew J. Baker
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Ontario, Canada
| | - C. David Mazer
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Ontario, Canada
| | - Gregory M. T. Hare
- Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada
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14
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Duffin J, Hare GM, Fisher JA. A mathematical model of cerebral blood flow control in anaemia and hypoxia. J Physiol 2020; 598:717-730. [DOI: 10.1113/jp279237] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/02/2019] [Indexed: 12/21/2022] Open
Affiliation(s)
- James Duffin
- Departments of Anaesthesia and PhysiologyUniversity of Toronto Toronto Ontario Canada
- Thornhill Research Inc. Toronto Ontario Canada
| | - Gregory M.T Hare
- Departments of Anaesthesia and PhysiologyUniversity of Toronto Toronto Ontario Canada
- Department of AnesthesiaKeenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St Michael's HospitalUnity Health Toronto Toronto Ontario Canada
| | - Joseph A. Fisher
- Departments of Anaesthesia and PhysiologyUniversity of Toronto Toronto Ontario Canada
- Thornhill Research Inc. Toronto Ontario Canada
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15
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Tezcan B, Bölükbaşı D, Şaylan A, Turan S, Yakın SS, Kazancı D, Özgök A, Yazıcıoğlu H. Effect of dilutional anemia that can be treated with only one unit of red blood cell transfusion on tissue oxygenation in cardiac surgery patients. Turk J Med Sci 2019; 49:1102-1108. [PMID: 31408294 PMCID: PMC7018202 DOI: 10.3906/sag-1901-213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Background/aim Cardiac surgery, especially in the presence of cardiopulmonary bypass (CPB), is associated with an inflammatory reaction that may promote microcirculatory alterations, in addition to the general impact on system hemodynamics. Anemia and transfusion make patients more susceptible to the deleterious effects of CPB. In this study, it was aimed to evaluate the effect of dilutional anemia, which is caused by CPB and can be treated with 1–2 units of red blood cell (RBC) transfusion, on global tissue oxygenation parameters in cardiac surgery patients. Materials and methods This prospective observational study comprised 127 patients who had a relatively stable operation period without any major anesthetic or surgical complications (e.g., operation duration >5 h, bleeding or hemodilution requiring more than 1–2 units of RBCs, or unstable hemodynamics, requiring inotropic support of more than 5 µg/kg/min dopamine). Patients were observationally divided into two groups: minimally transfused (Group Tr) and nontransfused (Group NTr). Global tissue oxygenation parameters were evaluated after anesthesia induction (T1) and at the end of the operation (T3) and compared between the groups. Results Group Tr consisted of patients who had significantly lower preoperative hemoglobin values than Group NTr patients. The dilutional anemia of all Group Tr patients could be corrected with 1 unit of RBCs. The lactate levels at T3, increment rates of lactate, and venoarterial carbon dioxide pressure difference (ΔpCO2) levels [(T3 – T1) : T1] in Group Tr were significantly higher than those in Group NTr. Conclusion Dilutional anemia as a result of CPB mostly occurs in patients with borderline preoperative hemoglobin concentrations and its correction with RBC transfusion does not normalize the degree of microcirculatory and oxygenation problems, which the patients are already prone to because of the nature of CPB. Preventing dilutional anemia and transfusion, especially in patients with preoperative borderline hemoglobin levels, may therefore reduce the burden of impaired microcirculation-associated organ failure in on-pump cardiac surgery.
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Affiliation(s)
- Büşra Tezcan
- Department of Intensive Care, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - Demet Bölükbaşı
- Department of Intensive Care, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - Alev Şaylan
- Department of Anesthesiology and Reanimation, İstanbul Lütfi Kırdar Education and Research Hospital, İstanbul, Turkey
| | - Sema Turan
- Department of Intensive Care, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - Sultan Sevim Yakın
- Department of Intensive Care, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - Dilek Kazancı
- Department of Intensive Care, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - Ayşegül Özgök
- Department of Anesthesiology and Reanimation, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - Hija Yazıcıoğlu
- Department of Anesthesiology and Reanimation, Ministry of Health Ankara City Hospital, Ankara, Turkey
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16
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Lactate Clearance Predicts Good Neurological Outcomes in Cardiac Arrest Patients Treated with Extracorporeal Cardiopulmonary Resuscitation. J Clin Med 2019; 8:jcm8030374. [PMID: 30889788 PMCID: PMC6462911 DOI: 10.3390/jcm8030374] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/09/2019] [Accepted: 03/11/2019] [Indexed: 12/14/2022] Open
Abstract
Background: We evaluated critically ill patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) due to cardiac arrest (CA) with respect to baseline characteristics and laboratory assessments, including lactate and lactate clearance for prognostic relevance. Methods: The primary endpoint was 30-day mortality. The impact on 30-day mortality was assessed by uni- and multivariable Cox regression analyses. Neurological outcome assessed by Glasgow Outcome Scale (GOS) was pooled into two groups: scores of 1–3 (bad GOS score) and scores of 4–5 (good GOS score). Results: A total of 93 patients were included in the study. Serum lactate concentration (hazard ratio (HR) 1.09; 95% confidence interval (CI) 1.04–1.13; p < 0.001), hemoglobin, (Hb; HR 0.87; 95% CI 0.79–0.96; p = 0.004), and catecholamine use were associated with 30-day-mortality. In a multivariable model, only lactate clearance (after 6 h; OR 0.97; 95% CI 0.94–0.997; p = 0.03) was associated with a good GOS score. The optimal cut-off of lactate clearance at 6 h for the prediction of a bad GOS score was at ≤13%. Patients with a lactate clearance at 6 h ≤13% evidenced higher rates of bad GOS scores (97% vs. 73%; p = 0.01). Conclusions: Whereas lactate clearance does not predict mortality, it was the sole predictor of good neurological outcomes and might therefore guide clinicians when to stop ECPR.
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17
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Saroha V, Josephson CD, Patel RM. Epidemiology of Necrotizing Enterocolitis: New Considerations Regarding the Influence of Red Blood Cell Transfusions and Anemia. Clin Perinatol 2019; 46:101-117. [PMID: 30771812 PMCID: PMC6383803 DOI: 10.1016/j.clp.2018.09.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
This article summarizes available evidence on the relationship between red blood cell transfusion and anemia, and necrotizing enterocolitis (NEC). We review recent studies that highlight the uncertainty of the effect of red blood cell transfusion on NEC and the potential role of anemia. We also discuss potential pathophysiologic effects of both red blood cell transfusion and anemia and highlight strategies to prevent anemia and red blood cell transfusion. We also discuss ongoing randomized trials that are likely to provide important new evidence to guide red blood cell transfusion practices.
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Affiliation(s)
- Vivek Saroha
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, 2015 Uppergate Dr. NE, 3 floor, Atlanta, GA 30322. Tel 404-727-3236.
| | - Cassandra D. Josephson
- Center for Transfusion and Cellular Therapies, Departments of Pathology and Laboratory Medicine and Pediatrics, Emory University School of Medicine, 101 Woodruff Cir, Atlanta, GA 30322. Tel 404-785-4553.
| | - Ravi Mangal Patel
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, 2015 Uppergate Dr. NE, 3 floor, Atlanta, GA 30322. Tel 404-727-3236.
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18
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Dhir A, Tempe DK. Anemia and Patient Blood Management in Cardiac Surgery—Literature Review and Current Evidence. J Cardiothorac Vasc Anesth 2018; 32:2726-2742. [DOI: 10.1053/j.jvca.2017.11.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Indexed: 12/24/2022]
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19
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Madeddu C, Gramignano G, Astara G, Demontis R, Sanna E, Atzeni V, Macciò A. Pathogenesis and Treatment Options of Cancer Related Anemia: Perspective for a Targeted Mechanism-Based Approach. Front Physiol 2018; 9:1294. [PMID: 30294279 PMCID: PMC6159745 DOI: 10.3389/fphys.2018.01294] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 08/28/2018] [Indexed: 01/28/2023] Open
Abstract
Cancer-related anemia (CRA) is a common sign occurring in more than 30% of cancer patients at diagnosis before the initiation of antineoplastic therapy. CRA has a relevant influence on survival, disease progression, treatment efficacy, and the patients' quality of life. It is more often detected in patients with advanced stage disease, where it represents a specific symptom of the neoplastic disease, as a consequence of chronic inflammation. In fact, CRA is characterized by biological and hematologic features that resemble those described in anemia associated to chronic inflammatory disease. Proinflammatory cytokine, mainly IL-6, which are released by both tumor and immune cells, play a pivotal action in CRA etiopathogenesis: they promote alterations in erythroid progenitor proliferation, erythropoietin (EPO) production, survival of circulating erythrocytes, iron balance, redox status, and energy metabolism, all of which can lead to anemia. The discovery of hepcidin allowed a greater knowledge of the relationships between immune cells, iron metabolism, and anemia in chronic inflammatory diseases. Additionally, chronic inflammation influences a compromised nutritional status, which in turn might induce or contribute to CRA. In the present review we examine the multifactorial pathogenesis of CRA discussing the main and novel mechanisms by which immune, nutritional, and metabolic components affect its onset and severity. Moreover, we analyze the status of the art and the perspective for the treatment of CRA. Notably, despite the high incidence and clinical relevance of CRA, controlled clinical studies testing the most appropriate treatment for CRA are scarce, and its management in clinical practice remains challenging. The present review may be useful to indicate the development of an effective approach based on a detailed assessment of all factors potentially involved in the pathogenesis of CRA. This mechanism-based approach is essential for clinicians to plan a safe, targeted, and successful therapy, thereby promoting a relevant amelioration of patients' quality of life.
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Affiliation(s)
- Clelia Madeddu
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | | | - Giorgio Astara
- Department of Medical Oncology, Azienda Ospedaliero Universitaria Cagliari, Cagliari, Italy
| | - Roberto Demontis
- Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
| | - Elisabetta Sanna
- Department of Gynecologic Oncology, Azienda Ospedaliera Brotzu, Cagliari, Italy
| | - Vinicio Atzeni
- Hospital Medical Management, Azienda Ospedaliera Brotzu, Cagliari, Italy
| | - Antonio Macciò
- Department of Gynecologic Oncology, Azienda Ospedaliera Brotzu, Cagliari, Italy
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20
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Restoration of cardiac function after anaemia-induced heart failure in zebrafish. J Mol Cell Cardiol 2018; 121:223-232. [PMID: 30009777 DOI: 10.1016/j.yjmcc.2018.07.128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 06/28/2018] [Accepted: 07/11/2018] [Indexed: 01/22/2023]
Abstract
AIMS New therapeutic approaches are needed to fight against the growing epidemic of heart failure. Unlike mammals, zebrafish possess the incredible ability to regenerate cardiac tissue after acute trauma such as apical resection. Yet, the ability of zebrafish to recover after a chronic stress leading to heart failure has not been reported. The aim of this study was to test whether zebrafish can recover a normal cardiac function after anaemia-induced heart failure. METHODS AND RESULTS Eight- to ten-month-old zebrafish were treated with phenylhydrazine hydrochloride, an anaemia inducer, to generate heart failure. Treatment was stopped after 5 weeks and fish were followed-up for 3 weeks. Assessment of ventricular function by ultrasound at the end of the treatment revealed an increase in ventricle diameter (+47%) and a decrease in heart rate (-36%) and fractional shortening (-30%). A decrease in swim capacity was also observed (-31%). Tissue staining showed a thickening of the ventricular wall (5-fold), cell apoptosis and proliferation but no fibrosis. Expression of foetal genes, angiogenic factor and inflammation markers was increased, and β-adrenergic receptor-1 was decreased. Three weeks after phenylhydrazine hydrochloride withdrawal, all parameters returned to baseline and the fish recovered a normal cardiac function, tissue morphology and gene expression. CONCLUSIONS Zebrafish are able to completely recover from anaemia-induced heart failure. This model represents a unique opportunity to investigate the mechanisms of cardiac repair and may lead to the discovery of novel therapeutic targets of heart failure.
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21
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Saito T, Okamura A, Inoue J, Makiura D, Doi H, Yakushijin K, Matsuoka H, Sakai Y, Ono R. Anemia Is a Novel Predictive Factor for the Onset of Severe Chemotherapy-Induced Peripheral Neuropathy in Lymphoma Patients Receiving Rituximab Plus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisolone Therapy. Oncol Res 2018; 27:469-474. [PMID: 30126466 PMCID: PMC7848272 DOI: 10.3727/096504018x15267574931782] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) frequently occurs in lymphoma patients receiving R-CHOP, a drug combination therapy. Although severe CIPN may lead to reduction and/or discontinuation of the medication, predictive factors of CIPN have not been investigated sufficiently to date. We performed a retrospective exploratory research to determine associations between prevalence of severe CIPN and sociodemographic data, health characteristics, and medical conditions such as anemia at initial diagnosis. Forty patients (indolent lymphoma, n = 9; diffuse large B-cell lymphoma; n = 31) received R-CHOP therapy from September 2009 to July 2014. The median age of patients was 58 years (range = 27–76 years). Statistical analyses were applied to the patients, who were divided into two groups: mild CIPN (no symptoms or grade 1 according to the CTCAE version 3.0 program) and severe CIPN patients (grade 2 or higher). Forward stepwise logistic regression analyses were performed using the following variables: sex, BMI, BSA, hyperglycemia, malnutrition, and anemia. Severe CIPN occurred in seven patients (17.5%). Gender and anemia remained following the stepwise procedure, and anemia predicted severe CIPN significantly (OR = 19.45, 95% confidence interval = 1.52–171.12). Our study suggests that anemia at initial diagnosis could be a predictive factor of R-CHOP-induced CIPN.
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Affiliation(s)
- Takashi Saito
- Department of Community Health Sciences, Kobe University Graduate School of Health Sciences, Kobe, Japan
| | - Atsuo Okamura
- Department of Medical Oncology and Hematology, Kakogawa Central City Hospital, Kakogawa, Japan
| | - Junichiro Inoue
- Division of Rehabilitation Medicine, Kobe University Hospital, Kobe, Japan
| | - Daisuke Makiura
- Division of Rehabilitation Medicine, Kobe University Hospital, Kobe, Japan
| | - Hisayo Doi
- Division of Nursing, Kobe University Hospital, Kobe, Japan
| | | | - Hiroshi Matsuoka
- Division of Medical Oncology and Hematology, Kobe University, Kobe, Japan
| | - Yoshitada Sakai
- Division of Rehabilitation Medicine, Kobe University Hospital, Kobe, Japan
| | - Rei Ono
- Department of Community Health Sciences, Kobe University Graduate School of Health Sciences, Kobe, Japan
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22
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Allwood MA, Edgett BA, Eadie AL, Huber JS, Romanova N, Millar PJ, Brunt KR, Simpson JA. Moderate and severe hypoxia elicit divergent effects on cardiovascular function and physiological rhythms. J Physiol 2018; 596:3391-3410. [PMID: 29604069 DOI: 10.1113/jp275945] [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: 02/05/2018] [Accepted: 03/29/2018] [Indexed: 12/26/2022] Open
Abstract
KEY POINTS In the present study, we provide evidence for divergent physiological responses to moderate compared to severe hypoxia, addressing an important knowledge gap related to severity, duration and after-effects of hypoxia encountered in cardiopulmonary situations. The physiological responses to moderate and severe hypoxia were not proportional, linear or concurrent with the time-of-day. Hypoxia elicited severity-dependent physiological responses that either persisted or fluctuated throughout normoxic recovery. The physiological basis for these distinct cardiovascular responses implicates a shift in the sympathovagal set point and probably not molecular changes at the artery resulting from hypoxic stress. ABSTRACT Hypoxia is both a consequence and cause of many acute and chronic diseases. Severe hypoxia causes hypertension with cardiovascular sequelae; however, the rare studies using moderate severities of hypoxia indicate that it can be beneficial, suggesting that hypoxia may not always be detrimental. Comparisons between studies are difficult because of the varied classifications of hypoxic severities, methods of delivery and use of anaesthetics. Thus, to investigate the long-term effects of moderate hypoxia on cardiovascular health, radiotelemetry was used to obtain in vivo physiological measurements in unanaesthetized mice during 24 h of either moderate (FIO2=0.15) or severe (FIO2=0.09) hypoxia, followed by 72 h of normoxic recovery. Systolic blood pressure was decreased during recovery following moderate hypoxia but increased following severe hypoxia. Moderate and severe hypoxia increased haeme oxygenase-1 expression during recovery, suggesting parity in hypoxic stress at the level of the artery. Severe but not moderate hypoxia increased the low/high frequency ratio of heart rate variability 72 h post-hypoxia, indicating a shift in sympathovagal balance. Moderate hypoxia dampened the amplitude of circadian rhythm, whereas severe disrupted rhythm during the entire insult, with perturbations persisting throughout normoxic recovery. Thus, hypoxic severity differentially regulates circadian blood pressure.
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Affiliation(s)
- Melissa A Allwood
- Department of Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, Canada
| | - Brittany A Edgett
- Department of Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, Canada
| | - Ashley L Eadie
- Department of Pharmacology, Dalhousie Medicine New Brunswick, 100 Tucker Park Road, Saint John, New Brunswick, Canada
| | - Jason S Huber
- Department of Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, Canada
| | - Nadya Romanova
- Department of Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, Canada
| | - Philip J Millar
- Department of Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, Canada
| | - Keith R Brunt
- Department of Pharmacology, Dalhousie Medicine New Brunswick, 100 Tucker Park Road, Saint John, New Brunswick, Canada
| | - Jeremy A Simpson
- Department of Human Health and Nutritional Sciences, University of Guelph, 50 Stone Road East, Guelph, ON, Canada
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23
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Potential biomarkers of tissue hypoxia during acute hemodilutional anemia in cardiac surgery: A prospective study to assess tissue hypoxia as a mechanism of organ injury. Can J Anaesth 2018; 65:901-913. [DOI: 10.1007/s12630-018-1140-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 03/15/2018] [Accepted: 03/16/2018] [Indexed: 02/08/2023] Open
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24
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Ngo JP, Evans RG. Multitasking: a challenge for the kidney. Am J Physiol Regul Integr Comp Physiol 2018; 314:R540-R541. [DOI: 10.1152/ajpregu.00011.2018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Jennifer P. Ngo
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Roger G. Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
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25
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Mistry N, Mazer CD, Sled JG, Lazarus AH, Cahill LS, Solish M, Zhou YQ, Romanova N, Hare AGM, Doctor A, Fisher JA, Brunt KR, Simpson JA, Hare GMT. Red blood cell antibody-induced anemia causes differential degrees of tissue hypoxia in kidney and brain. Am J Physiol Regul Integr Comp Physiol 2018; 314:R611-R622. [PMID: 29351418 DOI: 10.1152/ajpregu.00182.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Moderate anemia is associated with increased mortality and morbidity, including acute kidney injury (AKI), in surgical patients. A red blood cell (RBC)-specific antibody model was utilized to determine whether moderate subacute anemia could result in tissue hypoxia as a potential mechanism of injury. Cardiovascular and hypoxic cellular responses were measured in transgenic mice capable of expressing hypoxia-inducible factor-1α (HIF-1α)/luciferase activity in vivo. Antibody-mediated anemia was associated with mild intravascular hemolysis (6 h) and splenic RBC sequestration ( day 4), resulting in a nadir hemoglobin concentration of 89 ± 13 g/l on day 4. At this time point, renal tissue oxygen tension (PtO2) was decreased in anemic mice relative to controls (13.1 ± 4.3 vs. 20.8 ± 3.7 mmHg, P < 0.001). Renal tissue hypoxia was associated with an increase in HIF/luciferase expression in vivo ( P = 0.04) and a 20-fold relative increase in renal erythropoietin mRNA transcription ( P < 0.001) but no increase in renal blood flow ( P = 0.67). By contrast, brain PtO2 was maintained in anemic mice relative to controls (22.7 ± 5.2 vs. 23.4 ± 9.8 mmHg, P = 0.59) in part because of an increase in internal carotid artery blood flow (80%, P < 0.001) and preserved cerebrovascular reactivity. Despite these adaptive changes, an increase in brain HIF-dependent mRNA levels was observed (erythropoietin: P < 0.001; heme oxygenase-1: P = 0.01), providing evidence for subtle cerebral tissue hypoxia in anemic mice. These data demonstrate that moderate subacute anemia causes significant renal tissue hypoxia, whereas adaptive cerebrovascular responses limit the degree of cerebral tissue hypoxia. Further studies are required to assess whether hypoxia is a mechanism for acute kidney injury associated with anemia.
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Affiliation(s)
- Nikhil Mistry
- Department of Anesthesia, St. Michael's Hospital, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada
| | - C David Mazer
- Department of Anesthesia, St. Michael's Hospital, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada.,Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - John G Sled
- Mouse Imaging Centre, The Hospital for Sick Children , Toronto, Ontario , Canada.,Department of Medical Biophysics, University of Toronto , Toronto, Ontario , Canada
| | - Alan H Lazarus
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada.,Canadian Blood Services Centre for Innovation , Ottawa, Ontario , Canada
| | - Lindsay S Cahill
- Mouse Imaging Centre, The Hospital for Sick Children , Toronto, Ontario , Canada
| | - Max Solish
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Yu-Qing Zhou
- Mouse Imaging Centre, The Hospital for Sick Children , Toronto, Ontario , Canada
| | - Nadya Romanova
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph , Guelph, Ontario , Canada
| | - Alexander G M Hare
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Allan Doctor
- Department of Pediatrics, Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis , St. Louis, Missouri
| | - Joseph A Fisher
- Department of Physiology, University of Toronto , Toronto, Ontario , Canada.,Department of Anesthesia, Toronto General Hospital, University of Toronto , Toronto, Ontario , Canada
| | - Keith R Brunt
- Department of Pharmacology, Dalhousie University , Saint John, New Brunswick , Canada
| | - Jeremy A Simpson
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph , Guelph, Ontario , Canada
| | - Gregory M T Hare
- Department of Anesthesia, St. Michael's Hospital, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada.,Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada.,St. Michael's Hospital Center of Excellence in Patient Blood Management, University of Toronto, Toronto, Ontario, Canada
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26
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Brocherie F, Millet GP, D'Hulst G, Van Thienen R, Deldicque L, Girard O. Repeated maximal-intensity hypoxic exercise superimposed to hypoxic residence boosts skeletal muscle transcriptional responses in elite team-sport athletes. Acta Physiol (Oxf) 2018; 222. [PMID: 28103427 DOI: 10.1111/apha.12851] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 06/30/2016] [Accepted: 01/16/2017] [Indexed: 12/31/2022]
Abstract
AIM To determine whether repeated maximal-intensity hypoxic exercise induces larger beneficial adaptations on the hypoxia-inducible factor-1α pathway and its target genes than similar normoxic exercise, when combined with chronic hypoxic exposure. METHODS Lowland elite male team-sport athletes underwent 14 days of passive normobaric hypoxic exposure [≥14 h·day-1 at inspired oxygen fraction (Fi O2 ) 14.5-14.2%] with the addition of six maximal-intensity exercise sessions either in normobaric hypoxia (Fi O2 ~14.2%; LHTLH; n = 9) or in normoxia (Fi O2 20.9%; LHTL; n = 11). A group living in normoxia with no additional maximal-intensity exercise (LLTL; n = 10) served as control. Before (Pre), immediately after (Post-1) and 3 weeks after (Post-2) the intervention, muscle biopsies were obtained from the vastus lateralis. RESULTS Hypoxia-inducible factor-1α subunit, vascular endothelial growth factor, myoglobin, peroxisome proliferator-activated receptor-gamma coactivator 1-α and mitochondrial transcription factor A mRNA levels increased at Post-1 (all P ≤ 0.05) in LHTLH, but not in LHTL or LLTL, and returned near baseline levels at Post-2. The protein expression of citrate synthase increased in LHTLH (P < 0.001 and P < 0.01 at Post-1 and Post-2, respectively) and LLTL (P < 0.01 and P < 0.05 at Post-1 and Post-2, respectively), whereas it decreased in LHTL at Post-1 and Post-2 (both P < 0.001). CONCLUSION Combined with residence in normobaric hypoxia, repeated maximal-intensity hypoxic exercise induces short-term post-intervention beneficial changes in muscle transcriptional factors that are of larger magnitude (or not observed) than with similar normoxic exercise. The decay of molecular adaptations was relatively fast, with most of benefits already absent 3 weeks post-intervention.
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Affiliation(s)
- F. Brocherie
- ISSUL, Institute of Sports Sciences; University of Lausanne; Lausanne Switzerland
| | - G. P. Millet
- ISSUL, Institute of Sports Sciences; University of Lausanne; Lausanne Switzerland
| | - G. D'Hulst
- Institute of Neuroscience; Université catholique de Louvain; Louvain-la-Neuve Belgium
| | - R. Van Thienen
- Exercise Physiology Research Group; Department of Kinesiology; KU Leuven; Leuven Belgium
| | - L. Deldicque
- Exercise Physiology Research Group; Department of Kinesiology; KU Leuven; Leuven Belgium
- Institute of Neuroscience; Université catholique de Louvain; Louvain-la-Neuve Belgium
| | - O. Girard
- ISSUL, Institute of Sports Sciences; University of Lausanne; Lausanne Switzerland
- ASPETAR, Orthopaedic and Sports Medicine Hospital; Athlete Health and Performance Research Centre; Doha Qatar
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27
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Allali S, Brousse V, Sacri AS, Chalumeau M, de Montalembert M. Anemia in children: prevalence, causes, diagnostic work-up, and long-term consequences. Expert Rev Hematol 2017; 10:1023-1028. [PMID: 29023171 DOI: 10.1080/17474086.2017.1354696] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Anemia in children is a major public health problem throughout the world. It is often multifactorial, iron deficiency being the most frequent etiology. Consequences are diverse and largely under evaluated. Areas covered: This paper briefly reviews the main causes and focus on the potential consequences of acute and chronic anemia in children. Expert commentary: Anemia in children should never be trivialized. Even if iron deficiency is frequently involved, other potentially life-threatening causes are possible and should be looked for. The exact contribution of anemia to child mortality and morbidity is difficult to assess because of overlapping comorbidities. Chronic anemia may impair growth, cardiac function and cognitive development in infants but other consequences are rather poorly described and should be explored more thoroughly.
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Affiliation(s)
- Slimane Allali
- a Department of General Pediatrics and Pediatric Infectious Diseases , Hôpital Necker-Enfants malades , Paris , France
| | - Valentine Brousse
- a Department of General Pediatrics and Pediatric Infectious Diseases , Hôpital Necker-Enfants malades , Paris , France
| | - Anne-Sylvia Sacri
- a Department of General Pediatrics and Pediatric Infectious Diseases , Hôpital Necker-Enfants malades , Paris , France
| | - Martin Chalumeau
- a Department of General Pediatrics and Pediatric Infectious Diseases , Hôpital Necker-Enfants malades , Paris , France
| | - Mariane de Montalembert
- a Department of General Pediatrics and Pediatric Infectious Diseases , Hôpital Necker-Enfants malades , Paris , France.,b Laboratory of Excellence GR-Ex , Paris , France
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28
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Cahill LS, Gazdzinski LM, Tsui AK, Zhou YQ, Portnoy S, Liu E, Mazer CD, Hare GM, Kassner A, Sled JG. Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice. J Cereb Blood Flow Metab 2017; 37:994-1005. [PMID: 27165012 PMCID: PMC5363475 DOI: 10.1177/0271678x16649194] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia.
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Affiliation(s)
- Lindsay S Cahill
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Lisa M Gazdzinski
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Albert Ky Tsui
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Yu-Qing Zhou
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Sharon Portnoy
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Elaine Liu
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - C David Mazer
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,3 Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Gregory Mt Hare
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,3 Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Andrea Kassner
- 4 Department of Medical Imaging, University of Toronto and The Hospital for Sick Children, Toronto, Ontario, Canada
| | - John G Sled
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.,5 Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
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29
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Oxygen imaging of living cells and tissues using luminescent molecular probes. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2017. [DOI: 10.1016/j.jphotochemrev.2017.01.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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30
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Experimental assessment of oxygen homeostasis during acute hemodilution: the integrated role of hemoglobin concentration and blood pressure. Intensive Care Med Exp 2017; 5:12. [PMID: 28251580 PMCID: PMC5332316 DOI: 10.1186/s40635-017-0125-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 02/21/2017] [Indexed: 11/12/2022] Open
Abstract
Background Low hemoglobin concentration (Hb) and low mean arterial blood pressure (MAP) impact outcomes in critically ill patients. We utilized an experimental model of “normotensive” vs. “hypotensive” acute hemodilutional anemia to test whether optimal tissue perfusion is dependent on both Hb and MAP during acute blood loss and fluid resuscitation, and to assess the value of direct measurements of the partial pressure of oxygen in tissue (PtO2). Methods Twenty-nine anesthetized rats underwent 40% isovolemic hemodilution (1:1) (or sham-hemodilution control, n = 4) with either hydroxyethyl starch (HES) (n = 14, normotensive anemia) or saline (n = 11, hypotensive anemia) to reach a target Hb value near 70 g/L. The partial pressure of oxygen in the brain and skeletal muscle tissue (PtO2) were measured by phosphorescence quenching of oxygen using G4 Oxyphor. Mean arterial pressure (MAP), heart rate, temperature, arterial and venous co-oximetry, blood gases, and lactate were assessed at baseline and for 60 min after hemodilution. Cardiac output (CO) was measured at baseline and immediately after hemodilution. Data were analyzed by repeated measures two-way ANOVA. Results Following “normotensive” hemodilution with HES, Hb was reduced to 66 ± 6 g/L, CO increased (p < 0.05), and MAP was maintained. These conditions resulted in a reduction in brain PtO2 (22.1 ± 5.6 mmHg to 17.5 ± 4.4 mmHg, p < 0.05), unchanged muscle PO2, and an increase in venous oxygen extraction. Following “hypotensive” hemodilution with saline, Hb was reduced to 79 ± 5 g/L and both CO and MAP were decreased (P < 0.05). These conditions resulted in a more severe reduction in brain PtO2 (23.2 ± 8.2 to 10.7 ± 3.6 mmHg (p < 0.05), a reduction in muscle PtO2 (44.5 ± 11.0 to 19.9 ± 12.4 mmHg, p < 0.05), a further increase in venous oxygen extraction, and a threefold increase in systemic lactate levels (p < 0.05). Conclusions Acute normotensive anemia (HES hemodilution) was associated with a subtle decrease in brain tissue PtO2 without clear evidence of global tissue hypoperfusion. By contrast, acute hypotensive anemia (saline hemodilution) resulted in a profound decrease in both brain and muscle tissue PtO2 and evidence of inadequate global perfusion (lactic acidosis). These data emphasize the importance of maintaining CO and MAP to ensure adequacy of vital organ oxygen delivery during acute anemia. Improved methods of assessing PtO2 may provide an earlier warning signal of vital organ hypoperfusion.
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31
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Krömker M, Lauscher P, Kertscho H, Zacharowski K, Rosenberger P, Meier J. Anemia tolerance during normo-, hypo-, and hypervolemia. Transfusion 2016; 57:613-621. [PMID: 27990642 DOI: 10.1111/trf.13942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/23/2016] [Accepted: 10/24/2016] [Indexed: 01/10/2023]
Abstract
BACKGROUND Restrictive intraoperative fluid management has been demonstrated to improve outcome of visceral and lung surgery in several studies. However, subsequent hypovolemia (HOV) may be accompanied by a decrease of anemia tolerance, resulting in increased transfusion needs. We therefore investigated the effect of volume status on anemia tolerance. STUDY DESIGN AND METHODS Eighteen domestic pigs of either sex (mean weight, 23.5 ± 4.8 kg) were anesthetized, ventilated, and randomized into three experimental groups: normovolemia (no intervention), HOV (blood loss of 40% of blood volume), and hypervolemia (HEV; volume infusion of 40% of blood volume). The animals were then hemodiluted until their individual critical hemoglobin concentrations (Hbcrit ) were reached by the exchange of whole blood for hydroxyethyl starch (HES; 130:0.4). Subsequently, organ-specific hypoxia was assessed using pimonidazole tissue staining in relevant organs. Hemodynamic and metabolic variables were also investigated. RESULTS Despite significant differences in exchangeable blood volume, Hbcrit was the same in all groups (2.3 g/dL, NS). During HOV, tissue hypoxia was aggravated in the myocardium, brain, and kidneys, whereas tissue oxygenation of the liver and intestine was not influenced by volume status. HEV increased tissue hypoxia in the lungs, but did not impact tissue oxygenation of other organs. CONCLUSIONS The combination of hemorrhagic HOV with subsequent anemia leads to accentuated tissue hypoxia, revealed by a significant increase in pimonidazole binding at Hbcrit , in heart, lungs, brain, and kidney. The lungs were the only organ that showed increased tissue hypoxia after pretreatment of HES infusion and subsequent anemia by normovolemic hemodilution.
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Affiliation(s)
- Malte Krömker
- Clinic of Anesthesiology, Intensive Care Medicine and Pain Therapy, Sana Klinikum Offenbach, Offenbach, Germany
| | - Patrick Lauscher
- Clinic of Anesthesiology, Intensive Care Medicine and Pain Therapy, Sana Klinikum Offenbach, Offenbach, Germany
| | - Harry Kertscho
- Department of Anesthesiology and Critical Care Medicine, University Hospital Mannheim, Faculty of Medicine, University of Heidelberg, Heidelberg, Germany
| | - Kai Zacharowski
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Peter Rosenberger
- Clinic for Anesthesiology and Intensive Care Medicine, Eberhard Karls University, Tübingen, Germany
| | - Jens Meier
- Department of Anesthesiology and Critical Care Medicine, Faculty of Medicine of the Kepler University, Linz, Austria
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32
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Kosinski PD, Croal PL, Leung J, Williams S, Odame I, Hare GMT, Shroff M, Kassner A. The severity of anaemia depletes cerebrovascular dilatory reserve in children with sickle cell disease: a quantitative magnetic resonance imaging study. Br J Haematol 2016; 176:280-287. [DOI: 10.1111/bjh.14424] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/30/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Przemyslaw D. Kosinski
- Institute of Medical Science; University of Toronto; Toronto ON Canada
- Physiology and Experimental Medicine; The Hospital for Sick Children; Toronto ON Canada
| | - Paula L. Croal
- Physiology and Experimental Medicine; The Hospital for Sick Children; Toronto ON Canada
| | - Jackie Leung
- Physiology and Experimental Medicine; The Hospital for Sick Children; Toronto ON Canada
| | - Suzan Williams
- Division of Haematology/Oncology; The Hospital for Sick Children; Toronto ON Canada
| | - Isaac Odame
- Division of Haematology/Oncology; The Hospital for Sick Children; Toronto ON Canada
| | | | - Manohar Shroff
- Department of Diagnostic Imaging; The Hospital for Sick Children; Toronto ON Canada
| | - Andrea Kassner
- Physiology and Experimental Medicine; The Hospital for Sick Children; Toronto ON Canada
- Department of Diagnostic Imaging; The Hospital for Sick Children; Toronto ON Canada
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Erythropoietin improves hypoxic-ischemic encephalopathy in neonatal rats after short-term anoxia by enhancing angiogenesis. Brain Res 2016; 1651:104-113. [DOI: 10.1016/j.brainres.2016.09.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 09/09/2016] [Accepted: 09/17/2016] [Indexed: 01/05/2023]
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34
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Ferrara G, Kanoore Edul VS, Martins E, Canales HS, Canullán C, Murias G, Pozo MO, Estenssoro E, Ince C, Dubin A. Intestinal and sublingual microcirculation are more severely compromised in hemodilution than in hemorrhage. J Appl Physiol (1985) 2016; 120:1132-40. [DOI: 10.1152/japplphysiol.00007.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/10/2016] [Indexed: 11/22/2022] Open
Abstract
The alterations in O2 extraction in hemodilution have been linked to fast red blood cell (RBC) velocity, which might affect the complete release of O2 from Hb. Fast RBC velocity might also explain the normal mucosal-arterial Pco2 (ΔPco2). Yet sublingual and intestinal microcirculation have not been completely characterized in extreme hemodilution. Our hypothesis was that the unchanged ΔPco2 in hemodilution depends on the preservation of villi microcirculation. For this purpose, pentobarbital-anesthetized and mechanically ventilated sheep were submitted to stepwise hemodilution ( n = 8), hemorrhage ( n = 8), or no intervention (sham, n = 8). In both hypoxic groups, equivalent reductions in O2 consumption (V̇o2) were targeted. Microcirculation was assessed by videomicroscopy, intestinal ΔPco2 by air tonometry, and V̇o2 by expired gases analysis. Although cardiac output and superior mesenteric flow increased in hemodilution, from the very first step (Hb = 5.0 g/dl), villi functional vascular density and RBC velocity decreased (21.7 ± 0.9 vs. 15.9 ± 1.0 mm/mm2 and 1,033 ± 75 vs. 850 ± 79 μm/s, P < 0.01). In the last stage (Hb = 1.2 g/dl), these variables were lower in hemodiution than in hemorrhage (11.1 ± 0.5 vs. 15.4 ± 0.9 mm/mm2 and 544 ± 26 vs. 686 ± 70 μm/s, P < 0.01), and were associated with lower intestinal fractional O2 extraction (0.61 ± 0.04 vs. 0.79 ± 0.02, P < 0.01) but preserved ΔPco2 (5 ± 2 vs. 25 ± 4 mmHg, P < 0.01). Therefore, alterations in O2 extraction in hemodilution seemed related to microvascular shunting, not to fast RBC velocity. The severe microvascular abnormalities suggest that normal ΔPco2 was not dependent on CO2 washout by the villi microcirculation. Increased perfusion in deeper intestinal layers might be an alternative explanation.
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Affiliation(s)
- Gonzalo Ferrara
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Vanina Siham Kanoore Edul
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Enrique Martins
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Héctor Saúl Canales
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Carlos Canullán
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Gastón Murias
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Mario Omar Pozo
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Elisa Estenssoro
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
| | - Can Ince
- Academic Medical Center, Department of Translational Physiology, University of Amsterdam, Amsterdam, The Netherlands
| | - Arnaldo Dubin
- Cátedra de Farmacología Aplicada, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina; and
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35
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Evans RG. Oxygen regulation in biological systems. Am J Physiol Regul Integr Comp Physiol 2016; 310:R673-8. [PMID: 26911461 DOI: 10.1152/ajpregu.00004.2016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 02/17/2016] [Indexed: 01/25/2023]
Affiliation(s)
- Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Melbourne, Australia
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Favier FB, Britto FA, Freyssenet DG, Bigard XA, Benoit H. HIF-1-driven skeletal muscle adaptations to chronic hypoxia: molecular insights into muscle physiology. Cell Mol Life Sci 2015; 72:4681-96. [PMID: 26298291 PMCID: PMC11113128 DOI: 10.1007/s00018-015-2025-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 08/14/2015] [Accepted: 08/18/2015] [Indexed: 12/12/2022]
Abstract
Skeletal muscle is a metabolically active tissue and the major body protein reservoir. Drop in ambient oxygen pressure likely results in a decrease in muscle cells oxygenation, reactive oxygen species (ROS) overproduction and stabilization of the oxygen-sensitive hypoxia-inducible factor (HIF)-1α. However, skeletal muscle seems to be quite resistant to hypoxia compared to other organs, probably because it is accustomed to hypoxic episodes during physical exercise. Few studies have observed HIF-1α accumulation in skeletal muscle during ambient hypoxia probably because of its transient stabilization. Nevertheless, skeletal muscle presents adaptations to hypoxia that fit with HIF-1 activation, although the exact contribution of HIF-2, I kappa B kinase and activating transcription factors, all potentially activated by hypoxia, needs to be determined. Metabolic alterations result in the inhibition of fatty acid oxidation, while activation of anaerobic glycolysis is less evident. Hypoxia causes mitochondrial remodeling and enhanced mitophagy that ultimately lead to a decrease in ROS production, and this acclimatization in turn contributes to HIF-1α destabilization. Likewise, hypoxia has structural consequences with muscle fiber atrophy due to mTOR-dependent inhibition of protein synthesis and transient activation of proteolysis. The decrease in muscle fiber area improves oxygen diffusion into muscle cells, while inhibition of protein synthesis, an ATP-consuming process, and reduction in muscle mass decreases energy demand. Amino acids released from muscle cells may also have protective and metabolic effects. Collectively, these results demonstrate that skeletal muscle copes with the energetic challenge imposed by O2 rarefaction via metabolic optimization.
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Affiliation(s)
- F B Favier
- INRA, UMR 866 Dynamique Musculaire et Métabolisme, 34060, Montpellier, France.
- Université de Montpellier, 34090, Montpellier, France.
| | - F A Britto
- INRA, UMR 866 Dynamique Musculaire et Métabolisme, 34060, Montpellier, France
- Université de Montpellier, 34090, Montpellier, France
| | - D G Freyssenet
- Laboratoire de Physiologie de l'Exercice EA 4338, Université de Lyon, Université Jean Monnet, 42000, Saint Etienne, France
| | - X A Bigard
- Agence Française de Lutte contre le Dopage, 75007, Paris, France
| | - H Benoit
- INSERM, U1042 Hypoxie Physio-Pathologie, 38000, Grenoble, France
- Université Joseph Fourier, 38000, Grenoble, France
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Li G, Zhao Y, Li Y, Lu J. Up-Regulation of Neuronal Nitric Oxide Synthase Expression by Cobalt Chloride Through a HIF-1α Mechanism in Neuroblastoma Cells. Neuromolecular Med 2015; 17:443-53. [PMID: 26458913 DOI: 10.1007/s12017-015-8373-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/03/2015] [Indexed: 10/22/2022]
Abstract
Nitric oxide (NO) plays a dual role in response to neural hypoxia. NO is synthesized by three isoforms of nitric oxide synthase (NOS), among which the neuronal NOS (nNOS) is predominant in the nervous system. Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that is induced under hypoxic conditions, but its correlation with nNOS remains unclear. In the present study, we aimed at clarifying the regulation pattern of the nNOS expression in response to cobalt chloride (CoCl2), a widely used chemical mimic of hypoxia, and the role of HIF-1α in this process in neuroblastoma cells. We found CoCl2 evidently increased the nNOS expression and NO production in human neuroblastoma SK-N-SH cells, but the effect of CoCl2 on NO was partially abrogated by 7-nitroindazole, a selective inhibitor for nNOS. Importantly, we identified a hypoxia response element (HRE) within the nNOS promoter, to which HIF-1α may bind, and CoCl2 greatly enhanced the HIF-1α expression and its binding to the HRE. Meanwhile, we demonstrated that this HRE was functionally important for the activation of the nNOS transcription, and CoCl2 increased the transcriptional activity of the nNOS promoter through this HRE. Taken together, our study shows that CoCl2 may induce the nNOS expression and NO production through a HIF-1α mechanism in neuroblastoma cells, which may provide a potential target for the treatment of neurological hypoxic disorders caused by NO dysregulation.
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Affiliation(s)
- Guangyu Li
- Department of Neurosurgery, The First Affiliated Hospital, China Medical University, No. 155, Nanjing Street, Heping District, Shenyang, 110001, People's Republic of China.
| | - Yanyan Zhao
- Department of Medical Genetics, College of Basic Medical Science, China Medical University, No. 92, Bei Er Road, Heping District, Shenyang, 110001, People's Republic of China.
| | - Yinghui Li
- Department of Medical Genetics, College of Basic Medical Science, China Medical University, No. 92, Bei Er Road, Heping District, Shenyang, 110001, People's Republic of China
| | - Jingyu Lu
- Department of Medical Genetics, College of Basic Medical Science, China Medical University, No. 92, Bei Er Road, Heping District, Shenyang, 110001, People's Republic of China
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Fago A, Jensen FB. Hypoxia tolerance, nitric oxide, and nitrite: lessons from extreme animals. Physiology (Bethesda) 2015; 30:116-26. [PMID: 25729057 DOI: 10.1152/physiol.00051.2014] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Among vertebrates able to tolerate periods of oxygen deprivation, the painted and red-eared slider turtles (Chrysemys picta and Trachemys scripta) and the crucian carp (Carassius carassius) are the most extreme and can survive even months of total lack of oxygen during winter. The key to hypoxia survival resides in concerted physiological responses, including strong metabolic depression, protection against oxidative damage and-in air-breathing animals-redistribution of blood flow. Each of these responses is known to be tightly regulated by nitric oxide (NO) and during hypoxia by its metabolite nitrite. The aim of this review is to highlight recent work illustrating the widespread roles of NO and nitrite in the tolerance to extreme oxygen deprivation, in particular in the red-eared slider turtle and crucian carp, but also in diving marine mammals. The emerging picture underscores the importance of NO and nitrite signaling in the adaptive response to hypoxia in vertebrate animals.
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Affiliation(s)
- Angela Fago
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark; and
| | - Frank B Jensen
- Department of Biology, University of Southern Denmark, Odense, Denmark
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Yang F, Zhou L, Wang D, Wang Z, Huang QY. Minocycline ameliorates hypoxia-induced blood-brain barrier damage by inhibition of HIF-1α through SIRT-3/PHD-2 degradation pathway. Neuroscience 2015. [PMID: 26211444 DOI: 10.1016/j.neuroscience.2015.07.051] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Minocycline, a second-generation tetracycline alleviates neuro-inflammation and protects the blood-brain barrier (BBB) in ischemia stroke. However, the effect of minocycline in hypoxia-induced BBB damage is unclear. Here, we have investigated the effect of minocycline under hypoxia and explored its possible underlying mechanisms. METHODS The effect of minocycline was examined in vitro in Human Brain Microvascular Endothelial Cells (HBMECs) using Trans Epithelial Electric Resistance (TEER). Protein and mRNA expression of Hypoxia-Inducible Factors-1α (HIF-1α), matrix metalloproteinases (MMP-2 and MMP-9) and tight junction proteins (TJs) were detected by using Western blot and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The translocation and transcription of HIF-1α were detected by using immunocytochemistry and luciferase reporter assay. In vivo, to adult male Sprague Dawley (SD) rats under hypobaric hypoxia were administered minocycline for 1h and BBB permeability was tested by using Evans Blue and Transmission Electron Microscopy (TEM). Also, reduction of NAD-dependent deacetylase sirtuin-3 (SIRT-3)/proline hydroxylase-2 (PHD-2) signaling pathway was evaluated. RESULTS Minocycline increased TEER in HBMECs after hypoxia (P<0.05), and reduced the extravasation of Evans Blue (P<0.05) and colloidal gold nanoparticles in rats. Minocycline administration significantly reduced HIF-1α expression, protein and mRNA expression of MMP-2, MMP-9 and Vascular Endothelial Growth Factor (VEGF) (P<0.05), and increased TJs (ZO-1, claudin-5 and occluding) (P<0.05) in HBMECs after hypoxia. Furthermore, minocycline reversed the hypoxia-induced reduction of PHD-2 (P<0.05) and SIRT-3 (P<0.05). Effects of minocycline were abolished by siRNA-mediated knockdown of SIRT-3 in the brain. CONCLUSIONS Minocycline inhibits HIF-1α-mediated cellular responses and protects BBB integrity through SIRT-3/PHD-2 pathway, proving to be a potential drug for the prevention and treatment of hypoxic brain injuries.
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Affiliation(s)
- F Yang
- Department of Pathophysiology and High Altitude Pathology, College of High Altitude Military Medicine, Third Military Medical University, 30 Gaotanyan, Shapingba, Chongqing 400038, China; Key Laboratory of High Altitude Medicine (Third Military Medical University), Ministry of Education, China; Key Laboratory of High Altitude Medicine, PLA, China
| | - L Zhou
- Department of Pharmacology, Xinqiao Hospital & The Second Affiliated Hospital, The Third Military Medical University, Chongqing, China
| | - D Wang
- Department of Pathophysiology and High Altitude Pathology, College of High Altitude Military Medicine, Third Military Medical University, 30 Gaotanyan, Shapingba, Chongqing 400038, China; Key Laboratory of High Altitude Medicine (Third Military Medical University), Ministry of Education, China; Key Laboratory of High Altitude Medicine, PLA, China
| | - Z Wang
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
| | - Q-Y Huang
- Department of Pathophysiology and High Altitude Pathology, College of High Altitude Military Medicine, Third Military Medical University, 30 Gaotanyan, Shapingba, Chongqing 400038, China; Key Laboratory of High Altitude Medicine (Third Military Medical University), Ministry of Education, China; Key Laboratory of High Altitude Medicine, PLA, China.
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Ashmore T, Fernandez BO, Evans CE, Huang Y, Branco-Price C, Griffin JL, Johnson RS, Feelisch M, Murray AJ. Suppression of erythropoiesis by dietary nitrate. FASEB J 2014; 29:1102-12. [PMID: 25422368 PMCID: PMC4422362 DOI: 10.1096/fj.14-263004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In mammals, hypoxia-triggered erythropoietin release increases red blood cell mass to meet tissue oxygen demands. Using male Wistar rats, we unmask a previously unrecognized regulatory pathway of erythropoiesis involving suppressor control by the NO metabolite and ubiquitous dietary component nitrate. We find that circulating hemoglobin levels are modulated by nitrate at concentrations achievable by dietary intervention under normoxic and hypoxic conditions; a moderate dose of nitrate administered via the drinking water (7 mg NaNO3/kg body weight/d) lowered hemoglobin concentration and hematocrit after 6 d compared with nonsupplemented/NaCl-supplemented controls. The underlying mechanism is suppression of hepatic erythropoietin expression associated with the downregulation of tissue hypoxia markers, suggesting increased pO2. At higher nitrate doses, however, a partial reversal of this effect occurred; this was accompanied by increased renal erythropoietin expression and stabilization of hypoxia-inducible factors, likely brought about by the relative anemia. Thus, hepatic and renal hypoxia-sensing pathways act in concert to modulate hemoglobin in response to nitrate, converging at an optimal minimal hemoglobin concentration appropriate to the environmental/physiologic situation. Suppression of hepatic erythropoietin expression by nitrate may thus act to decrease blood viscosity while matching oxygen supply to demand, whereas renal oxygen sensing could act as a brake, averting a potentially detrimental fall in hematocrit.—Ashmore, T., Fernandez, B. O., Evans, C. E., Huang, Y., Branco-Price, C., Griffin, J. L., Johnson, R. S., Feelisch, M., Murray, A. J. Suppression of erythropoiesis by dietary nitrate.
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Affiliation(s)
- Tom Ashmore
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Bernadette O Fernandez
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Colin E Evans
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Yun Huang
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Cristina Branco-Price
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Julian L Griffin
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Randall S Johnson
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Martin Feelisch
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
| | - Andrew J Murray
- *Department of Physiology, Development, and Neuroscience and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; and Faculty of Medicine, Clinical and Experimental Sciences, University of Southampton, Southampton, United Kingdom
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Tufro A. Tubular vascular endothelial growth factor-a, erythropoietin, and medullary vessels: a trio linked by hypoxia. J Am Soc Nephrol 2014; 26:997-8. [PMID: 25385850 DOI: 10.1681/asn.2014101004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- Alda Tufro
- Section of Nephrology, Department of Pediatrics, Yale School of Medicine, New Haven, Connecticut
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Evans RG. Hypoxic signaling: some organs are more equal than others. Focus on "Differential HIF and NOS responses to acute anemia: defining organ-specific hemoglobin thresholds for tissue hypoxia". Am J Physiol Regul Integr Comp Physiol 2014; 307:R11-2. [PMID: 24760993 DOI: 10.1152/ajpregu.00524.2013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Roger G Evans
- Department of Physiology, Monash University, Melbourne, Australia
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