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De Chiara L, Conte C, Semeraro R, Diaz-Bulnes P, Angelotti ML, Mazzinghi B, Molli A, Antonelli G, Landini S, Melica ME, Peired AJ, Maggi L, Donati M, La Regina G, Allinovi M, Ravaglia F, Guasti D, Bani D, Cirillo L, Becherucci F, Guzzi F, Magi A, Annunziato F, Lasagni L, Anders HJ, Lazzeri E, Romagnani P. Tubular cell polyploidy protects from lethal acute kidney injury but promotes consequent chronic kidney disease. Nat Commun 2022; 13:5805. [PMID: 36195583 PMCID: PMC9532438 DOI: 10.1038/s41467-022-33110-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 09/02/2022] [Indexed: 11/09/2022] Open
Abstract
Acute kidney injury (AKI) is frequent, often fatal and, for lack of specific therapies, can leave survivors with chronic kidney disease (CKD). We characterize the distribution of tubular cells (TC) undergoing polyploidy along AKI by DNA content analysis and single cell RNA-sequencing. Furthermore, we study the functional roles of polyploidization using transgenic models and drug interventions. We identify YAP1-driven TC polyploidization outside the site of injury as a rapid way to sustain residual kidney function early during AKI. This survival mechanism comes at the cost of senescence of polyploid TC promoting interstitial fibrosis and CKD in AKI survivors. However, targeting TC polyploidization after the early AKI phase can prevent AKI-CKD transition without influencing AKI lethality. Senolytic treatment prevents CKD by blocking repeated TC polyploidization cycles. These results revise the current pathophysiological concept of how the kidney responds to acute injury and identify a novel druggable target to improve prognosis in AKI survivors. Acute kidney injury is frequent, often fatal and can leave survivors with chronic kidney disease. Here the authors show that tubular cell polyploidy reduces early fatality sustaining residual function but promotes chronic kidney disease, which can be prevented by blocking YAP1
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Affiliation(s)
- Letizia De Chiara
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Carolina Conte
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Roberto Semeraro
- Department of Experimental and Clinical Medicine, University of Florence, Florence, 50139, Italy
| | - Paula Diaz-Bulnes
- Translational immunology, Instituto de Investigación Sanitaria del Principado de Asturias ISPA, 33011, Oviedo, Asturias, España
| | - Maria Lucia Angelotti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Benedetta Mazzinghi
- Nephrology and Dialysis Unit, Meyer Children's University Hospital, Florence, 50139, Italy
| | - Alice Molli
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy.,Nephrology and Dialysis Unit, Meyer Children's University Hospital, Florence, 50139, Italy
| | - Giulia Antonelli
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Samuela Landini
- Medical Genetics Unit, Meyer Children's University Hospital, Florence, 50139, Italy
| | - Maria Elena Melica
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Anna Julie Peired
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Laura Maggi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, 50139, Italy
| | - Marta Donati
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Gilda La Regina
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Marco Allinovi
- Nephrology, Dialysis and Transplantation Unit, Careggi University Hospital, Florence, 50134, Italy
| | - Fiammetta Ravaglia
- Nephrology and Dialysis Unit, Santo Stefano Hospital, Prato, 59100, Italy
| | - Daniele Guasti
- Department of Experimental & Clinical Medicine, Imaging Platform, University of Florence, Florence, 50139, Italy
| | - Daniele Bani
- Department of Experimental & Clinical Medicine, Imaging Platform, University of Florence, Florence, 50139, Italy
| | - Luigi Cirillo
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy.,Nephrology and Dialysis Unit, Meyer Children's University Hospital, Florence, 50139, Italy
| | - Francesca Becherucci
- Nephrology and Dialysis Unit, Meyer Children's University Hospital, Florence, 50139, Italy
| | - Francesco Guzzi
- Nephrology and Dialysis Unit, Santo Stefano Hospital, Prato, 59100, Italy
| | - Alberto Magi
- Department of Information Engineering, University of Florence, Florence, 50139, Italy
| | - Francesco Annunziato
- Department of Experimental and Clinical Medicine, University of Florence, Florence, 50139, Italy.,Flow Cytometry Diagnostic Center and Immunotherapy (CDCI), Careggi University Hospital, Florence, 50134, Italy
| | - Laura Lasagni
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy
| | - Hans-Joachim Anders
- Division of Nephrology, Department of Internal Medicine IV, LMU Hospital, Munich, 80336, Germany
| | - Elena Lazzeri
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy.
| | - Paola Romagnani
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, 50139, Italy. .,Nephrology and Dialysis Unit, Meyer Children's University Hospital, Florence, 50139, Italy.
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2
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Plants with Therapeutic Potential for Ischemic Acute Kidney Injury: A Systematic Review. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:6807700. [PMID: 35656467 PMCID: PMC9152371 DOI: 10.1155/2022/6807700] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 03/30/2022] [Indexed: 11/18/2022]
Abstract
Acute kidney injury (AKI) is a complex condition which has an intricate pathology mostly involving hemodynamic, inflammatory, and direct toxic effects at the cellular level with high morbidity and mortality ratios. Renal ischemic reperfusion injury (RIRI) is the main factor responsible for AKI, most often observed in different types of shock, kidney transplantation, sepsis, and postoperative procedures. The RIRI-induced AKI is accompanied by increased reactive oxygen species generation together with the activation of various inflammatory pathways. In this context, plant-derived medicines have shown encouraging nephroprotective properties. Evidence provided in this systemic review leads to the conclusion that plant-derived extracts and compounds exhibit nephroprotective action against renal ischemic reperfusion induced-AKI by increasing endogenous antioxidants and decreasing anti-inflammatory cytokines. However, there is no defined biomarker or target which can be used for treating AKI completely. These plant-derived extracts and compounds are only tested in selected transgenic animal models. To develop the results obtained into a therapeutic entity, one should apply them in proper vertebrate multitransgenic animal models prior to further validation in humans.
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3
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Amini S, Robabi HN, Tashnizi MA, Vakili V. Selenium, Vitamin C and N-Acetylcysteine do not Reduce the Risk of Acute Kidney Injury after Off-Pump CABG: a Randomized Clinical Trial. Braz J Cardiovasc Surg 2019; 33:129-134. [PMID: 29898141 PMCID: PMC5985838 DOI: 10.21470/1678-9741-2017-0071] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 07/04/2017] [Indexed: 11/15/2022] Open
Abstract
Objective The aim of this study was to investigate the impact of perioperative
administration of N-acetylcysteine, selenium and vitamin C on the incidence
and outcomes of acute kidney injury after off-pump coronary bypass graft
surgery. Methods 291 patients requiring elective off-pump coronary bypass graft surgery were
randomized to receive either N-acetylcysteine, vitamin C and selenium 600
mg, 1500 mg, 0.5 mg, and nothing orally twice a day, respectively, from the
day before to 2 days after surgery. They were assessed for the development
of acute kidney injury using Acute Kidney Injury Network criteria, time of
onset, its severity and duration, duration of mechanical ventilation,
intensive care unit and hospital length of stay, and in-hospital
mortality. Results 272 patients completed the study. The total incidence of acute kidney injury
was 22.1% (n=60) with 14 (20.9%), 15 (22.1%), 21 (31.8%), and 10 (14.1%)
patients in the vitamin C, NAC, selenium, and control groups, respectively
(P=0.096). We did not register significant differences
in the incidence, the time of occurrence, the severity and the duration of
acute kidney injury, as well as the duration of mechanical ventilation, the
intensive care unit and hospital length of stay, and the in-hospital
mortality among the four groups. Conclusion We found that perioperative administration of N-acetylcysteine, vitamin C and
selenium were not effective in preventing acute kidney injury and associated
morbidity and mortality after off-pump coronary bypass graft surgery.
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Affiliation(s)
- Shahram Amini
- Department of Anesthesia, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hojat Naghavi Robabi
- Department of Anesthesiology and Critical Care, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Vida Vakili
- Department of Community Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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4
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Weisenthal SJ, Quill C, Farooq S, Kautz H, Zand MS. Predicting acute kidney injury at hospital re-entry using high-dimensional electronic health record data. PLoS One 2018; 13:e0204920. [PMID: 30458044 PMCID: PMC6245516 DOI: 10.1371/journal.pone.0204920] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 09/17/2018] [Indexed: 01/16/2023] Open
Abstract
Acute Kidney Injury (AKI), a sudden decline in kidney function, is associated with increased mortality, morbidity, length of stay, and hospital cost. Since AKI is sometimes preventable, there is great interest in prediction. Most existing studies consider all patients and therefore restrict to features available in the first hours of hospitalization. Here, the focus is instead on rehospitalized patients, a cohort in which rich longitudinal features from prior hospitalizations can be analyzed. Our objective is to provide a risk score directly at hospital re-entry. Gradient boosting, penalized logistic regression (with and without stability selection), and a recurrent neural network are trained on two years of adult inpatient EHR data (3,387 attributes for 34,505 patients who generated 90,013 training samples with 5,618 cases and 84,395 controls). Predictions are internally evaluated with 50 iterations of 5-fold grouped cross-validation with special emphasis on calibration, an analysis of which is performed at the patient as well as hospitalization level. Error is assessed with respect to diagnosis, race, age, gender, AKI identification method, and hospital utilization. In an additional experiment, the regularization penalty is severely increased to induce parsimony and interpretability. Predictors identified for rehospitalized patients are also reported with a special analysis of medications that might be modifiable risk factors. Insights from this study might be used to construct a predictive tool for AKI in rehospitalized patients. An accurate estimate of AKI risk at hospital entry might serve as a prior for an admitting provider or another predictive algorithm.
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Affiliation(s)
- Samuel J. Weisenthal
- Rochester Center for Health Informatics, University of Rochester Medical Center, Rochester, NY, United States of America
- Clinical Translational Science Institute, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Caroline Quill
- Rochester Center for Health Informatics, University of Rochester Medical Center, Rochester, NY, United States of America
- Clinical Translational Science Institute, University of Rochester Medical Center, Rochester, NY, United States of America
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Samir Farooq
- Rochester Center for Health Informatics, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Henry Kautz
- Department of Computer Science, University of Rochester, Rochester, NY, United States of America
- Goergen Institute for Data Science, University of Rochester, Rochester, NY, United States of America
| | - Martin S. Zand
- Rochester Center for Health Informatics, University of Rochester Medical Center, Rochester, NY, United States of America
- Clinical Translational Science Institute, University of Rochester Medical Center, Rochester, NY, United States of America
- Department of Medicine, Division of Nephrology, University of Rochester Medical Center, Rochester, NY, United States of America
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5
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Collett JA, Corridon PR, Mehrotra P, Kolb AL, Rhodes GJ, Miller CA, Molitoris BA, Pennington JG, Sandoval RM, Atkinson SJ, Campos-Bilderback SB, Basile DP, Bacallao RL. Hydrodynamic Isotonic Fluid Delivery Ameliorates Moderate-to-Severe Ischemia-Reperfusion Injury in Rat Kidneys. J Am Soc Nephrol 2017; 28:2081-2092. [PMID: 28122967 DOI: 10.1681/asn.2016040404] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 12/17/2016] [Indexed: 01/03/2023] Open
Abstract
Highly aerobic organs like the kidney are innately susceptible to ischemia-reperfusion (I/R) injury, which can originate from sources including myocardial infarction, renal trauma, and transplant. Therapy is mainly supportive and depends on the cause(s) of damage. In the absence of hypervolemia, intravenous fluid delivery is frequently the first course of treatment but does not reverse established AKI. Evidence suggests that disrupting leukocyte adhesion may prevent the impairment of renal microvascular perfusion and the heightened inflammatory response that exacerbate ischemic renal injury. We investigated the therapeutic potential of hydrodynamic isotonic fluid delivery (HIFD) to the left renal vein 24 hours after inducing moderate-to-severe unilateral IRI in rats. HIFD significantly increased hydrostatic pressure within the renal vein. When conducted after established AKI, 24 hours after I/R injury, HIFD produced substantial and statistically significant decreases in serum creatinine levels compared with levels in animals given an equivalent volume of saline via peripheral infusion (P<0.05). Intravital confocal microscopy performed immediately after HIFD showed improved microvascular perfusion. Notably, HIFD also resulted in immediate enhancement of parenchymal labeling with the fluorescent dye Hoechst 33342. HIFD also associated with a significant reduction in the accumulation of renal leukocytes, including proinflammatory T cells. Additionally, HIFD significantly reduced peritubular capillary erythrocyte congestion and improved histologic scores of tubular injury 4 days after IRI. Taken together, these results indicate that HIFD performed after establishment of AKI rapidly restores microvascular perfusion and small molecule accessibility, with improvement in overall renal function.
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Affiliation(s)
| | - Peter R Corridon
- Department of Craniofacial Biology, University of Colorado Denver, Anschutz Campus, Aurora, Colorado
| | | | - Alexander L Kolb
- Department of Biology, Indiana University-Purdue University, Indianapolis, Indiana; and
| | | | | | - Bruce A Molitoris
- Division of Nephrology, Department of Medicine.,Indiana Center for Biological Microscopy, Indiana University School of Medicine, Indianapolis, Indiana
| | | | | | - Simon J Atkinson
- Department of Biology, Indiana University-Purdue University, Indianapolis, Indiana; and
| | | | - David P Basile
- Department of Cellular and Integrative Physiology.,Division of Nephrology, Department of Medicine
| | - Robert L Bacallao
- Division of Nephrology, Department of Medicine, .,Department of Medicine, Division of Nephrology, Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana
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6
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Vafapour M, Nematbakhsh M, Monajemi R, Mazaheri S, Talebi A, Talebi N, Shirdavani S. Effect of Γ-aminobutyric acid on kidney injury induced by renal ischemia-reperfusion in male and female rats: Gender-related difference. Adv Biomed Res 2015; 4:158. [PMID: 26380243 PMCID: PMC4550949 DOI: 10.4103/2277-9175.161585] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 01/17/2015] [Indexed: 11/25/2022] Open
Abstract
Background: The most important cause of kidney injury is renal ischemia/reperfusion injury (IRI), which is gender-related. This study was designed to investigate the protective role of Γ-aminobutyric acid (GABA (against IRI in male and female rats. Materials and Methods: Thirty-six female and male wistar rats were assigned to six experimental groups. The IRI was induced by clamping renal vessels for 45 min then was performed reperfusion for 24 h. The group sex posed to IRI were pretreated with GABA and were compared with the control groups. Results: Serum levels of creatinine and blood urea nitrogen, kidney weight, and kidney tissue damage score increased in the IRI alone groups, (P < 0.05), while GABA decreased these parameters in female significantly (P < 0.05), but not in male rats. Uterus weight decreased significantly in female rats treated with GABA. Testis weight did not alter in male rats. Serum level of nitrite and kidney level of malondialdehyde (MDA) had no significant change in both female and male rats. Kidney level of nitrite increased significantly in female rats experienced IRI and serum level of MDA increased significantly in males that were exposed to IRI (P < 0.05). Conclusion: GABA could ameliorate kidney injury induced by renal IRI in a gender dependent manner.
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Affiliation(s)
- Marzieh Vafapour
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran ; Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
| | - Mehdi Nematbakhsh
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran ; Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran ; Isfahan-MN Institute of Basic and Applied Sciences Research, Isfahan, Iran
| | - Ramesh Monajemi
- Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
| | - Safoora Mazaheri
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ardeshir Talebi
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran ; Department of Clinical Pathology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Nahid Talebi
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran ; Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
| | - Soheyla Shirdavani
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
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7
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N-acetylcysteine Prevents Kidney and Lung Disturbances in Renal Ischemia/Reperfusion Injury in Rat. Int J Prev Med 2013; 4:1139-46. [PMID: 24319553 PMCID: PMC3843300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 08/08/2013] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND One of the most common causes of acute kidney injury (AKI) is kidney ischemia/reperfusion injury (IRI). The distant organ injury such as acute lung injury is one of the side effects of AKI or kidney IRI. In this study, we performed bilateral renal IRI in rats and the protective role of N-acetylcysteine (NAC) in kidney and lung was investigated. METHODS Rats (n = 30) were randomly assigned to four experiment groups. The group 1 was assigned as sham-operated group. Before kidney IRI performance, the others groups were treated with saline (group 2), 150 mg/kg (group 3) or 500 mg/kg (group 4) of NAC, and the treatment were continued daily after IRI for next 3 days. At day 3, the all groups' animals were subjected for the measurements. RESULTS The serum level of blood urea nitrogen (BUN) and creatinine (Cr) in the control group increased significantly (P < 0.05), and administration of NAC (150 mg/kg) decreased the serum levels of Cr and BUN. However, only the serum level of Cr decreased significantly (P < 0.05). NAC did not improve kidney weight and damage; however, its low dose (150 mg/kg) attenuated the lung injury score (P < 0.05) when compared with the control group. No significant differences were observed in lung water content and endothelial permeability, serum levels of malondialdehyde and nitrite between the groups. CONCLUSIONS Low dose of NAC as a protectant agent may protect the kidney function and lung tissue damage after kidney IRI.
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8
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Abstract
Acute kidney injury (AKI) is a serious complication for the critically ill patient. The term has been increasingly adopted over recent years as efforts have been made to capture and better define mild to severe renal dysfunction. Persistent AKI can lead to the subsequent development of renal failure recognized as an important determinant of morbidity and mortality in the critically ill patient. This article explores the clinical implications of AKI for the critically ill patient and how this can have a profound influence on the principal presenting disease and expected outcome.
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9
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Abstract
Postoperative acute renal failure (ARF) is a serious complication which can result in a prolonged hospital stay and a high mortality and morbidity. Underlying renal disease, cardiac diseases, nephrotoxin exposure and renal hypoperfusion are the possible predisposing risk factors which can create a high probability for the development of ARF. The incidence of ARF is highest after major vascular, cardiac and high-risk thoraco-abdominal surgery. Among the various renal protection strategies, adequate peri-operative volume expansion and avoidance of hypovolemia is the most accepted and practiced strategy. Numerous bio-markers of renal injury are used to estimate the presence and extent of renal insult and various new are currently under trial. Traditional pharmacological interventions like dopamine, diuretics and calcium antagonists are not currently the first line of reno-protective agents. The new non-pharmacological and pharmacological methods may improve outcome in renal transplantation, contrast-induced nephropathy and in various other settings of ARF. The current review is an attempt to refresh the knowledge and put forth the various renal protection strategies during the peri-operative period.
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Affiliation(s)
- Sukhminder Jit Singh Bajwa
- Department of Anesthesiology and Intensive Care, Gian Sagar Medical College and Hospital, Ram Nagar, Banur, Punjab, India
| | - Veenita Sharma
- Department of Anesthesiology and Intensive Care, Gian Sagar Medical College and Hospital, Ram Nagar, Banur, Punjab, India
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10
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Bipat R, Steels P, Cuypers Y, Toelsie JR. Mannitol Reduces the Hydrostatic Pressure in the Proximal Tubule of the Isolated Blood-Perfused Rabbit Kidney during Hypoxic Stress and Improves Its Function. NEPHRON EXTRA 2011; 1:201-11. [PMID: 22470393 PMCID: PMC3290862 DOI: 10.1159/000333478] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS Hypoxia may play a role in the development of renal failure in donated kidneys. In the present study, the effects of hypoxia on isolated blood-perfused rabbit kidneys were investigated and the effects of mannitol were explored, giving special attention to intratubular pressure. METHODS Kidneys were perfused with their autologous blood during four 30-min periods (P1-P4). P1 was considered baseline function. In P2, hypoxia was induced either alone or with an infusion of mannitol (15 mg/min) during P2-P4. Reoxygenation was applied after P2. Proximal intratubular pressure was measured in all conditions. RESULTS During hypoxia, renal blood flow doubled and restored immediately in P3. Urine flow stopped in P2, except in the series with mannitol, but gradually resumed in P3 and P4. Likewise, creatinine clearance recovered slightly (<25%) in P4, except for the series with mannitol, where it still could be measured in P2 and reached a value >50% of P1. Proximal intratubular pressure (mean ± SD) increased from 12 ± 5 in P1 to 24 ± 11 mm Hg during hypoxia and returned to 10 ± 6 mm Hg in P3. This increase was not observed with mannitol. CONCLUSION Cellular swelling might be responsible for the suppressed filtration during hypoxia and can be prevented by mannitol.
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Affiliation(s)
- Robbert Bipat
- Department of Physiology, Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname
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