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Dutta P, Layton AT. Sex and circadian regulation of metabolic demands in the rat kidney: A modeling analysis. PLoS One 2024; 19:e0293419. [PMID: 39018272 PMCID: PMC11253979 DOI: 10.1371/journal.pone.0293419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 10/12/2023] [Indexed: 07/19/2024] Open
Abstract
Renal hemodynamics, renal transporter expression levels, and urine excretion exhibit circadian variations. Disruption of these diurnal patterns is associated with the pathophysiology of hypertension and chronic kidney disease. Renal hemodynamics determines oxygen delivery, whereas renal transport and metabolism determines oxygen consumption; the balance between them yields renal oxygenation which also demonstrates 24-h periodicity. Another notable modulator of kidney function is sex, which has impacts on renal hemodynamics and transport function that are regulated by as well as independent of the circadian clock. The goal of this study was to investigate the diurnal and sexual variations in renal oxygen consumption and oxygenation. For this purpose, we developed computational models of rat kidney function that represent sexual dimorphism and circadian variation in renal hemodynamics and transporter activities. Model simulations predicted substantial differences in tubular Na+ transport and oxygen consumption among different nephron segments. We also simulated the effect of loop diuretics, which are used in the treatment of renal hypoxia, on medullary oxygen tension. Our model predicted a significantly higher effect of loop diuretics on medullary oxygenation in female rats compared to male rats and when administered during the active phase.
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Affiliation(s)
- Pritha Dutta
- Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario, Canada
| | - Anita T. Layton
- Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario, Canada
- Cheriton School of Computer Science, University of Waterloo, Waterloo, Ontario, Canada
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
- School of Pharmacy, University of Waterloo, Waterloo, Ontario, Canada
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Chang LY, Chao YL, Chiu CC, Chen PL, Lin HYH. Mitochondrial Signaling, the Mechanisms of AKI-to-CKD Transition and Potential Treatment Targets. Int J Mol Sci 2024; 25:1518. [PMID: 38338797 PMCID: PMC10855342 DOI: 10.3390/ijms25031518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/14/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
Acute kidney injury (AKI) is increasing in prevalence and causes a global health burden. AKI is associated with significant mortality and can subsequently develop into chronic kidney disease (CKD). The kidney is one of the most energy-demanding organs in the human body and has a role in active solute transport, maintenance of electrochemical gradients, and regulation of fluid balance. Renal proximal tubular cells (PTCs) are the primary segment to reabsorb and secrete various solutes and take part in AKI initiation. Mitochondria, which are enriched in PTCs, are the main source of adenosine triphosphate (ATP) in cells as generated through oxidative phosphorylation. Mitochondrial dysfunction may result in reactive oxygen species (ROS) production, impaired biogenesis, oxidative stress multiplication, and ultimately leading to cell death. Even though mitochondrial damage and malfunction have been observed in both human kidney disease and animal models of AKI and CKD, the mechanism of mitochondrial signaling in PTC for AKI-to-CKD transition remains unknown. We review the recent findings of the development of AKI-to-CKD transition with a focus on mitochondrial disorders in PTCs. We propose that mitochondrial signaling is a key mechanism of the progression of AKI to CKD and potential targeting for treatment.
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Affiliation(s)
- Li-Yun Chang
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (L.-Y.C.); (Y.-L.C.)
| | - Yu-Lin Chao
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (L.-Y.C.); (Y.-L.C.)
| | - Chien-Chih Chiu
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Phang-Lang Chen
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, CA 92697, USA;
| | - Hugo Y.-H. Lin
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (L.-Y.C.); (Y.-L.C.)
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
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Zhang J, Hu Z, Tan Y, Ye J. Causal relationship from heart failure to kidney function and CKD: A bidirectional two-sample mendelian randomization study. PLoS One 2023; 18:e0295532. [PMID: 38079381 PMCID: PMC10712866 DOI: 10.1371/journal.pone.0295532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Heart Failure (HF) is a widespread condition that affects millions of people, and it is caused by issues with the heart and blood vessels. Even though we know hypertension, coronary artery disease, obesity, diabetes, and genetics can increase the risk of HF and Chronic Kidney Disease (CKD), the exact cause of these conditions remains a mystery. To bridge this gap, we adopted Mendelian Randomization (MR), which relies on genetic variants as proxies. METHODS We used data from European populations for our Bidirectional Two-Sample MR Study, which included 930,014 controls and 47,309 cases of HF from the HERMES consortium, as well as 736,396 controls and 51,256 cases of CKD. We also employed several MR variations, including MR-Egger, Inverse Variance Weighted (IVW), and Weighted Median Estimator (WME), to guarantee the results were accurate and comprehensive.). RESULTS In this study, the MR analysis found that individuals with a genetic predisposition for HF have an elevated risk of CKD. Our study revealed a significant association between the genetic prediction of HF and the risk of CKD, as evidenced by the IVW method [with an odds ratio (OR) of 1.12 (95% CI, 1.03-1.21), p = 0.009] and the WME [with an OR of 1.14 (95% CI, 1.03-1.26), p = 0.008]. This causal relationship remained robust even after conducting MR analysis while adjusting for the effects of diabetes and hypertension, yielding ORs of 1.13 (IVW:95% CI, 1.03-1.23), 1.12 (MR-Egger: 95% CI, 0.85-1.48), and 1.15 (WME:95% CI, 1.04-1.27) (p = 0.008). However, in the reverse analysis aiming to explore CKD and renal function as exposures and HF as the outcome, we did not observe a statistically significant causal link between CKD and HF. CONCLUSION Our study demonstrates the significance of HF in CKD progression, thus having meaningful implications for treatment and the potential for discovering new therapies. To better understand the relationship between HF and CKD, we need to conduct research in a variety of populations.
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Affiliation(s)
- Junyu Zhang
- Institute of Traditional Chinese Medicine Diagnostics, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Zhixi Hu
- Institute of Traditional Chinese Medicine Diagnostics, Hunan University of Chinese Medicine, Changsha, Hunan, China
- Hunan Provincial Key Laboratory of Diagnostic Research in Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Yuquan Tan
- Institute of Traditional Chinese Medicine Diagnostics, Hunan University of Chinese Medicine, Changsha, Hunan, China
- Hunan Provincial Key Laboratory of Diagnostic Research in Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Jiahao Ye
- Institute of Traditional Chinese Medicine Diagnostics, Hunan University of Chinese Medicine, Changsha, Hunan, China
- Hunan Provincial Key Laboratory of Diagnostic Research in Chinese Medicine, Hunan University of Chinese Medicine, Changsha, Hunan, China
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Zhang K, Wang MD, Jiang SS, Tang L, Wang YF, Meng Y, Cai Z, Sun XY, Cui FQ, Zhao WJ. Is serum hemoglobin level an independent prognostic factor for IgA nephropathy?: a systematic review and meta-analysis of observational cohort studies. Ren Fail 2023; 45:2171885. [PMID: 36715437 PMCID: PMC9888460 DOI: 10.1080/0886022x.2023.2171885] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Decreased serum hemoglobin (Hb) level is associated with Immunoglobulin A nephropathy (IgAN) progression. However, whether serum Hb level is an independent prognostic factor of IgAN remains controversial. Herein, we aimed to investigate the prognostic value of serum Hb level in IgAN. METHODS The Cochrane Library, Embase, PubMed and Open Grey databases were systematically searched and reviewed. Kidney disease progression of IgAN was defined as a doubling of serum creatinine (SCr), a 30% reduction in estimated glomerular filtration rate (eGFR), end-stage renal disease (ESRD), or death. We evaluated the hazard ratio (HR) between serum Hb level and the incidence of kidney disease progression in IgAN before and after adjusting for relevant covariates. RESULTS We included nine studies with 10006 patients in the meta-analysis. As a continuous variable, we found that serum Hb was an independent prognostic factor of IgAN [unadjusted HR = 0.89, 95% confidence interval (CI) = 0.84-0.95, I2 = 98%; adjusted HR = 0.85, 95% CI = 0.79-0.91, I2 = 0%]. The sensitivity analysis confirmed the stability of these results. Consistently, as a dichotomous variable defined as the below/above cutoff for anemia, we observed a positive correlation between serum Hb and kidney disease progression in IgAN (unadjusted HR = 2.12, 95% CI = 1.44-3.12, I2 = 79%; adjusted HR = 1.65, 95% CI = 1.20-2.27, I2 = 0%). CONCLUSION Serum Hb level was independently correlated with the incidence of kidney disease progression in IgAN.
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Affiliation(s)
- Kang Zhang
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Meng-di Wang
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Shang-shang Jiang
- Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Long Tang
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Yue-fen Wang
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Yuan Meng
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Zhen Cai
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Xue-yan Sun
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Fang-qiang Cui
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
| | - Wen-jing Zhao
- Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China,CONTACT Wen-jing Zhao Department of Nephrology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China
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Mapuskar KA, Pulliam CF, Zepeda-Orozco D, Griffin BR, Furqan M, Spitz DR, Allen BG. Redox Regulation of Nrf2 in Cisplatin-Induced Kidney Injury. Antioxidants (Basel) 2023; 12:1728. [PMID: 37760031 PMCID: PMC10525889 DOI: 10.3390/antiox12091728] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/30/2023] [Accepted: 09/03/2023] [Indexed: 09/29/2023] Open
Abstract
Cisplatin, a potent chemotherapeutic agent, is marred by severe nephrotoxicity that is governed by mechanisms involving oxidative stress, inflammation, and apoptosis pathways. The transcription factor Nrf2, pivotal in cellular defense against oxidative stress and inflammation, is the master regulator of the antioxidant response, upregulating antioxidants and cytoprotective genes under oxidative stress. This review discusses the mechanisms underlying chemotherapy-induced kidney injury, focusing on the role of Nrf2 in cancer therapy and its redox regulation in cisplatin-induced kidney injury. We also explore Nrf2's signaling pathways, post-translational modifications, and its involvement in autophagy, as well as examine redox-based strategies for modulating Nrf2 in cisplatin-induced kidney injury while considering the limitations and potential off-target effects of Nrf2 modulation. Understanding the redox regulation of Nrf2 in cisplatin-induced kidney injury holds significant promise for developing novel therapeutic interventions. This knowledge could provide valuable insights into potential strategies for mitigating the nephrotoxicity associated with cisplatin, ultimately enhancing the safety and efficacy of cancer treatment.
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Affiliation(s)
- Kranti A. Mapuskar
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA
| | - Casey F. Pulliam
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA
| | - Diana Zepeda-Orozco
- Pediatric Nephrology and Hypertension at Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Kidney and Urinary Tract Center, Abigail Wexner Research Institute, Nationwide Children’s Hospital, Columbus, OH 43205, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Benjamin R. Griffin
- Division of Nephrology, The University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA
- Department of Internal Medicine, The University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA
| | - Muhammad Furqan
- Department of Internal Medicine, The University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA
| | - Douglas R. Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA
| | - Bryan G. Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA
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Tholén M, Kolsrud O, Dellgren G, Karason K, Lannemyr L, Ricksten SE. Atrial natriuretic peptide in the prevention of acute renal dysfunction after heart transplantation-a randomized placebo-controlled double-blind trial. Acta Anaesthesiol Scand 2023; 67:738-745. [PMID: 36941798 DOI: 10.1111/aas.14241] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/10/2023] [Accepted: 03/15/2023] [Indexed: 03/23/2023]
Abstract
BACKGROUND Acute kidney injury (AKI) and renal dysfunction after heart transplantation are common and serious complications. Atrial natriuretic peptide (ANP) has been shown to increase glomerular filtration rate (GFR) and exert renoprotective effects when used for the prevention/treatment of AKI in cardiac surgery. We tested the hypothesis that intraoperative and postoperative administration of ANP could prevent a postoperative decrease in renal function early after heart transplantation. METHODS Seventy patients were randomized to receive either ANP (50 ng/kg/min) (n = 33) or placebo (n = 37) starting after induction of anesthesia and continued for 4 days after heart transplantation or until treatment with dialysis was started. The primary end-point of the present study was measured GFR (mGFR) at day 4, assessed by plasma clearance of a renal filtration marker. Also, the incidence of postoperative AKI and dialysis were assessed. RESULTS Median (IQR) mGFR at day 4 postoperatively was 60.0 (57.0) and 50.1 (36.3) ml/min/1.72 m2 for the placebo and ANP groups, respectively (p = .705). During ongoing ANP infusion, the need for dialysis was 21.6% and 9.1% for the placebo and ANP groups, respectively (p = .197). The incidences of AKI for the placebo and the ANP groups were 76.5% and 63.6%, respectively (p = .616). The incidences of AKI stage 1 were 32.4% and 21.2% for the placebo and ANP groups, respectively (p = .420) and for AKI stage 2 or 3, 37.8% and 42.4%, respectively (p = .808). CONCLUSION The study failed to detect that ANP infusion attenuates renal dysfunction or decreases the incidence of AKI after heart transplantation.
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Affiliation(s)
- Maria Tholén
- Department of Anesthesiology and Intensive Care Medicine, Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Oscar Kolsrud
- Department of Cardiothoracic Surgery, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Göran Dellgren
- Department of Cardiothoracic Surgery, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
- Deparment of Transplantation Surgery, Institute of Transplantation, University of Gothenburg, Gothenburg, Sweden
| | - Kristjan Karason
- Deparment of Transplantation Surgery, Institute of Transplantation, University of Gothenburg, Gothenburg, Sweden
- Department of Cardiology, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Lukas Lannemyr
- Department of Anesthesiology and Intensive Care Medicine, Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Sven-Erik Ricksten
- Department of Anesthesiology and Intensive Care Medicine, Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden
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Wu JC, Wang XJ, Zhu JH, Huang XY, Liu M, Qiao Z, Zhang Y, Sun Y, Wang ZY, Zhan P, Zhang T, Hu HL, Liu H, Tang W, Yi F. GPR97 deficiency ameliorates renal interstitial fibrosis in mouse hypertensive nephropathy. Acta Pharmacol Sin 2023; 44:1206-1216. [PMID: 36635422 PMCID: PMC10203364 DOI: 10.1038/s41401-022-01041-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/12/2022] [Indexed: 01/13/2023] Open
Abstract
Hypertensive nephropathy (HTN) ranks as the second-leading cause of end-stage renal disease (ESRD). Accumulating evidence suggests that persistent hypertension injures tubular cells, leading to tubulointerstitial fibrosis (TIF), which is involved in the pathogenesis of HTN. G protein-coupled receptors (GPCRs) are implicated in many important pathological and physiological processes and act as important drug targets. In this study, we explored the intrarenal mechanisms underlying hypertension-associated TIF, and particularly, the potential role of GPR97, a member of the adhesion GPCR subfamily, in TIF. A deoxycorticosterone acetate (DOCA)/salt-induced hypertensive mouse model was used. We revealed a significantly upregulated expression of GPR97 in the kidneys, especially in renal tubules, of the hypertensive mice and 10 patients with biopsy-proven hypertensive kidney injury. GPR97-/- mice showed markedly elevated blood pressure, which was comparable to that of wild-type mice following DOCA/salt treatment, but dramatically ameliorated renal injury and TIF. In NRK-52E cells, we demonstrated that knockdown of GPR97 suppressed the activation of TGF-β signaling by disturbing small GTPase RhoA-mediated cytoskeletal reorganization, thus inhibiting clathrin-mediated endocytosis of TGF-β receptors and subsequent Smad activation. Collectively, this study demonstrates that GPR97 contributes to hypertension-associated TIF at least in part by facilitating TGF-β signaling, suggesting that GPR97 is a pivotal intrarenal factor for TIF progression under hypertensive conditions, and therapeutic strategies targeting GPR97 may improve the outcomes of patients with HTN.
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Affiliation(s)
- Ji-Chao Wu
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Xiao-Jie Wang
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Jing-Han Zhu
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Xue-Ying Huang
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Min Liu
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Zhe Qiao
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Yan Zhang
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Yu Sun
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Zi-Ying Wang
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Tao Zhang
- Department of Biostatistics, School of Public Health, Shandong University, Jinan, 250012, China
| | - Hui-Li Hu
- Department of Systems Biomedicine and Research Center of Stem Cell and Regenerative Medicine, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China
| | - Hong Liu
- State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250012, China
| | - Wei Tang
- Department of Pathogenic Biology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China.
| | - Fan Yi
- The Key Laboratory of Infection and Immunity of Shandong Province, Department of Pharmacology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, China.
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Bentley C, Williams TL, Constantino-Casas F, Genain MA. The ultrasonographic appearance of renal medullary striations and their association with renal disease and renal histopathology in domestic cats. Vet Radiol Ultrasound 2023; 64:314-321. [PMID: 36281213 DOI: 10.1111/vru.13177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 08/14/2022] [Accepted: 08/16/2022] [Indexed: 11/29/2022] Open
Abstract
Medullary striations (MS) have been anecdotally observed on ultrasound of feline kidneys; however, their significance is unknown. Aims of this retrospective, case control, pilot study were to describe the appearance, prevalence, and clinicopathological correlates of MS in a referral feline population. Still images from 1247 feline abdominal ultrasound studies performed between 2011 and 2021 were reviewed. Cats with MS were identified and compared with age-matched controls. Serum urea, creatinine, calcium, phosphate, and calcium-phosphate-product, plus urine specific gravity, urine protein: creatinine ratio (UPC), prevalence of active sediment (defined as > 5 red (RBC) or white blood cells (WBC) per high-power field) and prevalence of positive urine culture were compared between MS and control groups using the Mann-Whitney U test or Fisher's Exact test. Data are presented as median [range]. 27 cats were identified as having MS, giving a prevalence of 2.2% with a significantly higher proportion being seen in males (P = 0.018). Medullary striation cats had significantly higher UPC values than controls (0.46 [0.16-7.57] vs. 0.16 [0.07-2.27]; P = 0.006). Cats with MS were more likely to have active urinary sediments (39% vs 8%, P = 0.023), but no difference in prevalence of positive urinary cultures was observed between groups. There was no significant difference in other parameters between MS and control cats. Renal histopathology performed in three MS cats revealed focal regions of linear medullary fibrosis. Medullary striations are associated with proteinuria and urinary tract inflammation in cats, which may reflect renal tubular dysfunction and/or inflammation. Hence identification might allow for earlier detection of renal pathology.
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Affiliation(s)
- Carli Bentley
- The Queen's Veterinary School Hospital. Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Tim L Williams
- The Queen's Veterinary School Hospital. Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Fernando Constantino-Casas
- The Queen's Veterinary School Hospital. Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Marie-Aude Genain
- The Queen's Veterinary School Hospital. Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
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9
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Mkolo NM, Olaokun OO, King PH, Janse van Rensburg I, Eloff JN, Naidoo V. Verification of the folkloric and anecdotal antidiabetic effects of Hypoxis hemerocallidea (Fisch., C.A. Mey. & Avé-Lall) and isolated, β-sitosterol using early-stage type II spontaneous diabetic mutant BKS-Leprdb mice. BMC Complement Med Ther 2022; 22:163. [PMID: 35725532 PMCID: PMC9208228 DOI: 10.1186/s12906-022-03640-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 06/09/2022] [Indexed: 11/25/2022] Open
Abstract
Background Previous studies in our laboratory in ex vivo assays have demonstrated H. hemerocallidea extract as potential antidiabetic agent through increased insulin release from pancreatic beta cells. Thus, for this study the early stage type II spontaneous diabetic mutant mice model was used to evaluate and determine the degree of the antidiabetic efficacy of H. hemerocallidea. Methods Eight-weeks-old type II spontaneous pre-diabetic mutant BKS-Leprdb mice were fed with feed supplemented with either H. hemerocallidea extract, isolated compound (β-sitosterol) or chlorpropamide (positive control) for 4 weeks. The haematological parameters, clinical chemistry, glucose tolerance, feed intake, faecal output and body weights were measured. Results The blood glucose concentrations of all the animals treated with plant extract, β-sitosterol compound and non-treated pre-diabetic animals did not return to baseline levels. Only the β-sitosterol treatment and positive control groups resulted in a respective small decrease of 5.8 and 5.2% in the mouse weights over the study period, with no significant changes (p > 0.05) in food intake. However, there was a general trend for decrease in faecal output for all the groups. Albumin, triglycerides, and total cholesterol levels in β-sitosterol and chlorpropamide-treated animals were lower, relative to untreated-animals. Animals fed with plant extract showed large amounts of internal fat. There were no significant changes (p > 0.05) in total serum protein, globulin, alanine aminotransferase, alkaline phosphatase, urea nitrogen and creatinine attributed to administration of treatments. In all groups, some animals showed lesions associated with cardiac puncture. Few animals except animals treated with plant extract, showed presence of a left-ventricular hypertrophic cardiomyopathy. The liver and kidneys for all groups appeared macroscopically normal and the thymuses were small (±2 mg). There were pathological signs in some of the animals particularly in myocardial fibres, renal tubular, glomerular, hepatocyte granularity and pancreas islets. However, there was no significance trend between the groups. Conclusion Based on the results, none of the treatments could be considered highly effective for the management of type II pre-diabetes as sole therapeutic intervention. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03640-y.
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10
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Liao L, Duan L, Guo Y, Zhou B, Xu Q, Zhang C, Liu W, Liu W, Liu Z, Hu J, Chen J, Lu J. TRIM46 upregulates Wnt/β-catenin signaling by inhibiting Axin1 to mediate hypoxia-induced epithelial-mesenchymal transition in HK2 cells. Mol Cell Biochem 2022; 477:2829-2839. [PMID: 35670901 DOI: 10.1007/s11010-022-04467-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 05/02/2022] [Indexed: 10/18/2022]
Abstract
Hypoxia can cause Epithelial-mesenchymal transition (EMT) in renal tubular cells, and in turn, renal fibrosis. We tested the expression of TRIM46, a member of tripartite motif-containing (TRIM) family proteins, and mesenchymal markers under hypoxia. Our results showed that hypoxia significantly enhanced expression of TRIM46 in HK2 human renal proximal tubular epithelial cells. Our data further showed that hypoxia led to upregulated expression of mesenchymal markers including α-smooth muscle actin, vimentin, and Snail, and downregulated expression of epithelial marker E-cadherin, coupled with an increased abundance of nuclear β-catenin. However, such effects were reversed when TRIM46 expression was knocked down. TRIM46 overexpression had similar effects as hypoxia exposure, and such effects were reversed when cells were treated with XAV-939, a selective inhibitor for β-catenin. Furthermore, we found that TRIM46 promoted ubiquitination and proteasomal degradation of Axin1 protein, a robust negative regulator of Wnt/β-catenin signaling activity. Finally, increased TRIM46 coupled with decreased Axin1 was observed in a rat renal fibrosis model. These data suggest a novel mechanism contributing to EMT that mediates hypoxia-induced renal fibrosis. Our results suggest that selectively inhibiting this pathway that activates fibrosis in human kidney may lead to development of a novel therapeutic approach for managing this disease.
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Affiliation(s)
- Lin Liao
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Lianxiang Duan
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Yue Guo
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Baojuan Zhou
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Qiming Xu
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Chuanfu Zhang
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Weiwei Liu
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Wenrui Liu
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Ziyang Liu
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Jing Hu
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China
| | - Jie Chen
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China.
| | - Jianrao Lu
- Department of Nephrology, Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, No.358 Datong Road in Pudong New District, Shanghai, 200137, China.
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11
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Kobayashi H, Davidoff O, Pujari‐Palmer S, Drevin M, Haase VH. EPO synthesis induced by HIF-PHD inhibition is dependent on myofibroblast transdifferentiation and colocalizes with non-injured nephron segments in murine kidney fibrosis. Acta Physiol (Oxf) 2022; 235:e13826. [PMID: 35491502 PMCID: PMC9329237 DOI: 10.1111/apha.13826] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 04/14/2022] [Accepted: 04/28/2022] [Indexed: 12/22/2022]
Abstract
AIM Erythropoietin (EPO) is regulated by hypoxia-inducible factor (HIF)-2. In the kidney, it is produced by cortico-medullary perivascular interstitial cells, which transdifferentiate into collagen-producing myofibroblasts in response to injury. Inhibitors of prolyl hydroxylase domain (PHD) dioxygenases (HIF-PHIs) activate HIF-2 and stimulate kidney and liver EPO synthesis in patients with anemia of chronic kidney disease (CKD). We examined whether HIF-PHIs can reactivate EPO synthesis in interstitial cells that have undergone myofibroblast transdifferentiation in established kidney fibrosis. METHODS We investigated Epo transcription in myofibroblasts and characterized the histological distribution of kidney Epo transcripts by RNA in situ hybridization combined with immunofluorescence in mice with adenine nephropathy (AN) treated with HIF-PHI molidustat. Lectin absorption chromatography was used to assess liver-derived EPO. In addition, we examined kidney Epo transcription in Phd2 knockout mice with obstructive nephropathy. RESULTS In AN, molidustat-induced Epo transcripts were not found in areas of fibrosis and did not colocalize with interstitial cells that expressed α-smooth muscle actin, a marker of myofibroblast transdifferentiation. Epo transcription was associated with megalin-expressing, kidney injury molecule 1-negative nephron segments and contingent on residual renal function. Liver-derived EPO did not contribute to serum EPO in molidustat-treated mice. Epo transcription was not associated with myofibroblasts in Phd2 knockout mice with obstructive nephropathy. CONCLUSIONS Our studies suggest that HIF-PHIs do not reactivate Epo transcription in interstitial myofibroblasts and that their efficacy in inducing kidney EPO in CKD is dependent on the degree of myofibroblast formation, the preservation of renal parenchyma and the level of residual renal function.
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Affiliation(s)
- Hanako Kobayashi
- Department of Medicine Vanderbilt University Medical Center and Vanderbilt University School of Medicine Nashville Tennessee USA
- Medical and Research Services Department of Veterans Affairs Hospital Tennessee Valley Healthcare System Nashville Tennessee USA
| | - Olena Davidoff
- Department of Medicine Vanderbilt University Medical Center and Vanderbilt University School of Medicine Nashville Tennessee USA
- Medical and Research Services Department of Veterans Affairs Hospital Tennessee Valley Healthcare System Nashville Tennessee USA
| | | | | | - Volker H. Haase
- Department of Medicine Vanderbilt University Medical Center and Vanderbilt University School of Medicine Nashville Tennessee USA
- Medical and Research Services Department of Veterans Affairs Hospital Tennessee Valley Healthcare System Nashville Tennessee USA
- Department of Molecular Physiology & Biophysics and Program in Cancer Biology Vanderbilt University School of Medicine Nashville Tennessee USA
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12
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Sivertsson E, Friederich-Persson M, Persson P, Nangaku M, Hansell P, Palm F. Thyroid hormone increases oxygen metabolism causing intrarenal tissue hypoxia; a pathway to kidney disease. PLoS One 2022; 17:e0264524. [PMID: 35239685 PMCID: PMC8893624 DOI: 10.1371/journal.pone.0264524] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 02/11/2022] [Indexed: 01/10/2023] Open
Abstract
The proposed mechanisms for the development of nephropathy are many, complex and often overlapping. Although recent literature strongly supports a role of kidney hypoxia as an independent pathway to nephropathy, the evidence remains inconclusive since the role of hypoxia is difficult to differentiate from confounding factors such as hyperglycemia, hypertension and oxidative stress. By increasing kidney oxygen consumption using triiodothyronine (T3) and, thus, avoiding these confounding factors, the aim of the present study was to investigate renal hypoxia per se as a causal pathway for the development of nephropathy. Healthy Sprague-Dawley rats were treated with T3 (10 μg/kg/day) and the angiotensin II AT1-receptor antagonist candesartan (1 mg/kg in drinking water) to eliminate effects of T3-induced renin release; and compared to a candesartan treated control group. After 7 weeks of treatment in vivo kidney function, oxygen metabolism and mitochondrial function were evaluated. T3 did not affect glomerular filtration rate or renal blood flow, but increased total kidney oxygen consumption resulting in cortical hypoxia. Nephropathy, demonstrated as albuminuria and tubulointerstitial fibrosis, developed in T3-treated animals. Mitochondria uncoupling mediated by uncoupling protein 2 and the adenosine nucleotide transporter was demonstrated as a mechanism causing the increased kidney oxygen consumption. Importantly, blood glucose levels, mean arterial blood pressure and oxidative stress levels were not affected by T3. In conclusion, the present study provides further evidence for increased kidney oxygen consumption causing intrarenal tissue hypoxia, as a causal pathway for development of nephropathy.
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Affiliation(s)
- Ebba Sivertsson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | - Patrik Persson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | - Peter Hansell
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Fredrik Palm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- * E-mail:
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13
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Early post-operative P V-ACO 2/C A-VO 2 predicts subsequent acute kidney injury after complete repair of tetralogy of Fallot. Cardiol Young 2022; 32:558-563. [PMID: 34210376 DOI: 10.1017/s1047951121002559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Acute kidney injury is a severe complication following complete repair of tetralogy of Fallot. Anaerobic metabolism is believed to contribute to the development of acute kidney injury. The ratio of central venous to arterial carbon dioxide tension to arterio-venous oxygen content (PV-ACO2/CA-VO2) has been proposed as a surrogate for respiratory quotient and an indicator of tissue oxygenation. We hypothesised that a small increase of PV-ACO2/CA-VO2 might have superior discrimination ability in subsequent acute kidney injury prediction. METHODS This study is retrospective and single-centre design study. The study population consisted of 61 children with tetralogy of Fallot that underwent a complete surgical repair between July 2017 and January 2021. Baseline characteristics and intra-operative parameters were collected through a retrospective chart review. PV-ACO2/CA-VO2 was collected within 12 hours of surgical completion. Acute kidney injury was defined according to the criteria established by the Kidney Disease: Improving Global Outcomes group. Univariate and logistic regression analyses were performed to determine risk factors for acute kidney injury. RESULTS Of the 61 patients, 20 (32.8%) developed acute kidney injury. Multivariate logistic analyses showed that age, height, haematocrit, and Pv-aCO2/Ca-vO2 were independently associated with the development of acute kidney injury. The addition of Pv-aCO2/Ca-vO2 to the model significantly increased model discrimination [AUROC 0.939 (95% CI 0.894-0.984) and AUROC 0.922 (95% CI 0.869-0.975), respectively]. CONCLUSIONS The increase of PV-ACO2/CA-VO2 could improve the predictive ability for subsequent development of acute kidney injury in children with tetralogy of Fallot.
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14
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Wang R, Wang S, Zhang J, He M, Xu J. Serum Lactate Level in Early Stage Is Associated With Acute Kidney Injury in Traumatic Brain Injury Patients. Front Surg 2022; 8:761166. [PMID: 35174203 PMCID: PMC8841417 DOI: 10.3389/fsurg.2021.761166] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/24/2021] [Indexed: 01/27/2023] Open
Abstract
Background Acute kidney injury (AKI) is a common complication in the clinical practice of managing patients with traumatic brain injury (TBI). Avoiding the development of AKI is beneficial for the prognosis of patients with TBI. We designed this study to testify whether serum lactate could be used as a predictive marker of AKI in patients with TBI. Materials and Methods In total, 243 patients with TBI admitted to our hospital were included in this study. Univariate and multivariate logistic regression analyses were utilized to analyze the association between lactate and AKI. The receiver operating characteristic (ROC) curves were drawn to verify the predictive value of lactate and the logistic model. Results Acute kidney injury group had higher age (p = 0.016), serum creatinine (p < 0.001), lactate (p < 0.001), and lower Glasgow Coma Scale (GCS; p = 0.021) than non-AKI group. Multivariate logistic regression showed that age [odds ratio (OR) = 1.026, p = 0.022], serum creatinine (OR = 1.020, p = 0.010), lactate (OR = 1.227, p = 0.031), fresh frozen plasma (FFP) transfusion (OR = 2.421, p = 0.045), and platelet transfusion (OR = 5.502, p = 0.044) were risk factors of AKI in patients with TBI. The area under the ROC curve (AUC) values of single lactate and predictive model were 0.740 and 0.807, respectively. Conclusion Serum lactate level in the early phase is associated with AKI in patients with TBI. Lactate is valuable for clinicians to evaluate the probability of AKI in patients with TBI.
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Affiliation(s)
- Ruoran Wang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
| | - Shaobo Wang
- Department of Infectious Diseases, Xi'an Hospital of Traditional Chinese Medicine, Xi'an, China
| | - Jing Zhang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
| | - Min He
- Department of Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Min He
| | - Jianguo Xu
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
- Jianguo Xu
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15
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Minutolo R, Provenzano M, Chiodini P, Borrelli S, Garofalo C, Andreucci M, Liberti ME, Bellizzi V, Conte G, De Nicola L, De Nicola L, Minutolo R, Zamboli P, Iodice FC, Borrelli S, Chiodini P, Signoriello S, Gallo C, Conte G, Cianciaruso B, Pota A, Nappi F, Avella F, Di Iorio BR, Bellizzi V, Cestaro R, Martignetti V, Morrone L, Lupo A, Abaterusso C, Donadio C, Bonomini M, Sirolli V, Casino F, Lopez T, Detomaso F, Giannattasio M, Virgilio M, Tarantino G, Cristofano C, Tuccillo S, Chimienti S, Petrarulo F, Giancaspro V, Strippoli M, Laraia E, Gallucci M, Gigante B, Lodeserto C, Santese D, Montanaro A, Giordano R, Caglioti A, Fuiano G, Zoccali C, Caridi G, Postorino M, Savica V, Monardo P, Bellinghieri G, Santoro D, Castellino P, Rapisarda F, Fatuzzo P, Messina A, Dal Canton A, Esposito V, Formica M, Segoloni G, Gallieni M, Locatelli F, Tarchini R, Meneghel G, Oldrizzi L, Cossu M, Di Giulio S, Malaguti M, Pizzarelli F, Quintaliani G, Cianciaruso B, Pisani A, Conte G, De Nicola L, Minutolo R, Bonofiglio R, Fuiano G, Grandaliano G, Bellinghieri G, Santoro D, Cianciaruso B, Russo D, Pota A, Di Micco L, Torraca S, Sabbatini M, Pisani A, Bellizzi V. New-Onset Anemia and Associated Risk of ESKD and Death in Non-Dialysis CKD Patients: A Multi-Cohort Observational Study. Clin Kidney J 2022; 15:1120-1128. [PMID: 35664282 PMCID: PMC9155211 DOI: 10.1093/ckj/sfac004] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Indexed: 12/03/2022] Open
Abstract
Background Anemia is a common complication of chronic kidney disease (CKD), but its incidence in nephrology settings is poorly investigated. Similarly, the risks of adverse outcomes associated with new-onset anemia are not known. Methods We performed a pooled analysis of three observational cohort studies including 1031 non-anemic CKD patients with eGFR <60 mL/min/1.73 m2 regularly followed in renal clinics. We estimated the incidence of mild anemia (hemoglobin 11–12 g/dL in women and 11–13 g/dL in men) and severe anemia (hemoglobin <11 g/dL or use of erythropoiesis-stimulating agents) during a 3-year follow-up period. Thereafter we estimated the risk of end-stage kidney disease (ESKD) and all-cause death associated with new-onset mild and severe anemia. Results The mean age was 63 ± 14 years, 60% were men and 20% had diabetes. The mean estimated glomerular filtration rate (eGFR) was 37 ± 13 mL/min/1.73 m2 and the median proteinuria was 0.4 g/day [interquartile range (IQR) 0.1–1.1]. The incidence of mild and severe anemia was 13.7/100 patients-year and 6.2/100 patients-year, respectively. Basal predictors of either mild or severe anemia were diabetes, lower hemoglobin, higher serum phosphate, eGFR <30 mL/min/1.73 m2 and proteinuria >0.50 g/day. Male sex, moderate CKD (eGFR 30–44 mL/min/1.73 m2) and moderate proteinuria (0.15–0.50 g/day) predicted only mild anemia. The incidence of anemia increased progressively with CKD stages (from 8.77 to 76.59/100 patients-year) and the proteinuria category (from 13.99 to 25.02/100 patients-year). During a median follow-up of 3.1 years, 232 patients reached ESKD and 135 died. Compared with non-anemic patients, mild anemia was associated with a higher adjusted risk of ESKD {hazard ratio [HR] 1.42 [95% confidence interval (CI) 1.02–1.98]} and all-cause death [HR 1.55 (95% CI 1.04–2.32)]. Severe anemia was associated with an even higher risk of ESKD [HR 1.73 (95% CI 1.20–2.51)] and death [HR 1.83 (95% CI 1.05–3.19)]. Conclusions New-onset anemia is frequent, particularly in patients with more severe renal damage and in those with diabetes mellitus. The occurrence of anemia, even of a mild degree, is associated with mortality risk and faster progression towards ESKD.
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Affiliation(s)
- Roberto Minutolo
- Nephrology Unit at University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Michele Provenzano
- Nephrology Unit, “Magna Graecia”, Department of Health Sciences, “Magna Graecia”, University of Catanzaro, Italy, Catanzaro, Italy
| | - Paolo Chiodini
- Medical Statistics Unit, University of Campania “Luigi Vanvitelli” Naples
| | - Silvio Borrelli
- Nephrology Unit at University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Carlo Garofalo
- Nephrology Unit at University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Michele Andreucci
- Nephrology Unit, “Magna Graecia”, Department of Health Sciences, “Magna Graecia”, University of Catanzaro, Italy, Catanzaro, Italy
| | | | - Vincenzo Bellizzi
- Nephrology Unit, University Hospital “San Giovanni di Dio e Ruggi d'Aragona” in Salerno, Italy
| | - Giuseppe Conte
- Nephrology Unit at University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Luca De Nicola
- Nephrology Unit at University of Campania “Luigi Vanvitelli”, Naples, Italy
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Burmakin M, Fasching A, Kobayashi H, Urrutia AA, Damdimopoulos A, Palm F, Haase VH. Pharmacological HIF-PHD inhibition reduces renovascular resistance and increases glomerular filtration by stimulating nitric oxide generation. Acta Physiol (Oxf) 2021; 233:e13668. [PMID: 33900001 DOI: 10.1111/apha.13668] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 04/14/2021] [Accepted: 04/19/2021] [Indexed: 12/11/2022]
Abstract
AIM Hypoxia-inducible factors (HIFs) are O2 -sensitive transcription factors that regulate multiple biological processes which are essential for cellular adaptation to hypoxia. Small molecule inhibitors of HIF-prolyl hydroxylase domain (PHD) dioxygenases (HIF-PHIs) activate HIF-dependent transcriptional programs and have broad clinical potential. HIF-PHIs are currently in global late-stage clinical development for the treatment of anaemia associated with chronic kidney disease. Although the effects of hypoxia on renal haemodynamics and function have been studied in animal models and in humans living at high altitude, the effects of pharmacological HIF activation on renal haemodynamics, O2 metabolism and metabolic efficiency are not well understood. METHODS Using a cross-sectional study design, we investigated renal haemodynamics, O2 metabolism, gene expression and NO production in healthy rats treated with different doses of HIF-PHIs roxadustat or molidustat compared to vehicle control. RESULTS Systemic administration of roxadustat or molidustat resulted in a dose-dependent reduction in renovascular resistance (RVR). This was associated with increased glomerular filtration rate (GFR), urine flow and tubular sodium transport rate (TNa ). Although both total O2 delivery and TNa were increased, more O2 was extracted per transported sodium in rats treated with high-doses of HIF-PHIs, suggesting a reduction in metabolic efficiency. Changes in RVR and GFR were associated with increased nitric oxide (NO) generation and substantially suppressed by pharmacological inhibition of NO synthesis. CONCLUSIONS Our data provide mechanistic insights into dose-dependent effects of short-term pharmacological HIF activation on renal haemodynamics, glomerular filtration and O2 metabolism and identify NO as a major mediator of these effects.
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Affiliation(s)
- Mikhail Burmakin
- Section of Integrative Physiology Department of Medical Cell Biology Uppsala University Uppsala Sweden
| | - Angelica Fasching
- Section of Integrative Physiology Department of Medical Cell Biology Uppsala University Uppsala Sweden
| | - Hanako Kobayashi
- Department of Medicine Vanderbilt University Medical Center and Vanderbilt University School of Medicine Nashville TN USA
| | - Andrés A. Urrutia
- Unidad de Investigación Hospital de Santa CristinaInstituto de Investigación del Hospital Universitario La PrincesaUniversidad Autónoma de Madrid Madrid Spain
| | - Anastasios Damdimopoulos
- Bioinformatics and Expression Analysis Core Facility Department of Biosciences and Nutrition Karolinska Institute Stockholm Sweden
| | - Fredrik Palm
- Section of Integrative Physiology Department of Medical Cell Biology Uppsala University Uppsala Sweden
| | - Volker H. Haase
- Section of Integrative Physiology Department of Medical Cell Biology Uppsala University Uppsala Sweden
- Department of Medicine Vanderbilt University Medical Center and Vanderbilt University School of Medicine Nashville TN USA
- Department of Molecular Physiology and Biophysics Vanderbilt University School of Medicine Nashville TN USA
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17
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Spencer S, Wheeler-Jones C, Elliott J. Hypoxia and chronic kidney disease: Possible mechanisms, therapeutic targets, and relevance to cats. Vet J 2021; 274:105714. [PMID: 34252550 DOI: 10.1016/j.tvjl.2021.105714] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 07/01/2021] [Accepted: 07/06/2021] [Indexed: 10/20/2022]
Abstract
There is mounting evidence that kidney ischaemia/hypoxia plays an important role in feline chronic kidney disease (CKD) development and progression, as well as in human disease and laboratory animal models. Ischaemic acute kidney injury is widely accepted as a cause of CKD in people and data from laboratory species has identified some of the pathways underlying this continuum. Experimental kidney ischaemia in cats results in morphological changes, namely chronic tubulointerstitial inflammation, tubulointerstitial fibrosis, and tubular atrophy, akin to those observed in naturally-occurring CKD. Multiple situations are envisaged that could result in acute or chronic episodes of kidney hypoxia in cats, while risk factors identified in epidemiological studies provide further support that kidney hypoxia contributes to spontaneously occurring feline CKD. This review evaluates the evidence for the role of kidney ischaemia/hypoxia in feline CKD and the proposed mechanisms and consequences of kidney hypoxia. As no effective treatments exist that substantially slow or prevent feline CKD progression, there is a need for novel therapeutic strategies. Targeting kidney hypoxia is one such promising approach, with therapies including those that attenuate the hypoxia-inducible factor (HIF) pathway already being utilised in human CKD.
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Affiliation(s)
- Sarah Spencer
- Comparative Biomedical Sciences, The Royal Veterinary College, Royal College Street, London NW1 0TU, UK.
| | - Caroline Wheeler-Jones
- Comparative Biomedical Sciences, The Royal Veterinary College, Royal College Street, London NW1 0TU, UK
| | - Jonathan Elliott
- Comparative Biomedical Sciences, The Royal Veterinary College, Royal College Street, London NW1 0TU, UK
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18
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Lourenço BN, Schmiedt CW, Alabady MS, Stanton JB, Coleman AE, Brown CA, Rissi DR, Brown SA, Tarigo JL. Analysis of genes associated with proinflammatory and profibrotic pathways upregulated in ischemia-induced chronic kidney disease in cats. Am J Vet Res 2021; 82:589-597. [PMID: 34166083 DOI: 10.2460/ajvr.82.7.589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To use RNA sequencing (RNAseq) to characterize renal transcriptional activities of genes associated with proinflammatory and profibrotic pathways in ischemia-induced chronic kidney disease (CKD) in cats. SAMPLES Banked renal tissues from 6 cats with experimentally induced CKD (renal ischemia [RI] group) and 9 healthy cats (control group). PROCEDURES Transcriptome analysis with RNAseq, followed by gene ontology and cluster analyses, were performed on banked tissue samples of the right kidneys (control kidneys) from cats in the control group and of both kidneys from cats in the RI group, in which unilateral (right) RI had been induced 6 months before the cats were euthanized and the ischemic kidneys (IKs) and contralateral nonischemic kidneys (CNIKs) were harvested. Results for the IKs, CNIKs, and control kidneys were compared to identify potential differentially expressed genes and overrepresented proinflammatory and profibrotic pathways. RESULTS Genes from the gene ontology pathways of collagen binding (eg, transforming growth factor-β1), metalloendopeptidase activity (eg, metalloproteinase [MMP]-7, MMP-9, MMP-11, MMP-13, MMP-16, MMP-23B, and MMP-28), chemokine activity, and T-cell migration were overrepresented as upregulated in tissue samples of the IKs versus control kidneys. Genes associated with the extracellular matrix (eg, TIMP-1, fibulin-1, secreted phosphoprotein-1, matrix Gla protein, and connective tissue growth factor) were upregulated in tissue samples from both the IKs and CNIKs, compared with tissues from the control kidneys. CONCLUSIONS AND CLINICAL RELEVANCE Unilateral ischemic injury differentially altered gene expression in both kidneys, compared with control kidneys. Fibulin-1, secreted phosphoprotein-1, and matrix Gla protein may be candidate biomarkers of active kidney injury in cats.
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Affiliation(s)
- Bianca N Lourenço
- From the Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Chad W Schmiedt
- From the Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Magdy S Alabady
- From the Department of Plant Biology, Franklin College of Arts and Sciences, and Georgia Genomics and Bioinformatics Core, University of Georgia, Athens, GA 30602
| | - James B Stanton
- From the Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Amanda E Coleman
- From the Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Cathy A Brown
- From the Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Daniel R Rissi
- From the Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Scott A Brown
- From the Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
- From the Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
| | - Jaime L Tarigo
- From the Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602
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19
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Chen F, Yan H, Yang F, Cheng L, Zhang S, Li S, Liu C, Xu K, Sun D. Evaluation of Renal Tissue Oxygenation Using Blood Oxygen Level-Dependent Magnetic Resonance Imaging in Chronic Kidney Disease. Kidney Blood Press Res 2021; 46:441-451. [PMID: 34091454 DOI: 10.1159/000515709] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/08/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) has been widely used to assess renal oxygenation changes in different kidney diseases in recent years. This study was designed to evaluate and compare renal tissue oxygenation using 2 BOLD-MRI analysis methods, namely, the regional and whole-kidney region of interest (ROI) selection methods. METHODS The study ended up with 10 healthy controls and 40 chronic kidney disease (CKD) patients without dialysis. Their renal BOLD-MRI data were analyzed using whole-kidney ROI selection method and compared with regional ROI selection method. RESULTS We found the cortical, medullary, and whole-kidney R2* values were significantly higher in CKD patients than those in controls. Compared with the regional ROI selection method, the whole-kidney ROI selection method yielded higher cortical R2* values in both controls and CKD patients. The whole-kidney R2* values of deteriorating renal function group were significantly higher than those in stable renal function group. CONCLUSIONS Cortical and medullary oxygenation was decreased significantly in CKD patients compared with the healthy controls, particularly in the medulla. The whole-kidney R2* values were positively correlated with kidney function and inversely correlated with the estimated glomerular filtration rate and effective renal plasma flow. Whole-Kidney R2* value might effectively predict the progression of renal function in patients with CKD.
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Affiliation(s)
- Fen Chen
- Department of Nephrology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.,Department of Internal Medicine and Diagnostics, Xuzhou Medical University, Xuzhou, China
| | - Han Yan
- Department of Nephrology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.,Department of Internal Medicine and Diagnostics, Xuzhou Medical University, Xuzhou, China
| | - Fan Yang
- Department of Nephrology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.,Department of Internal Medicine and Diagnostics, Xuzhou Medical University, Xuzhou, China
| | - Li Cheng
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Siwei Zhang
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Shulin Li
- Department of Nephrology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Caixia Liu
- Department of Nephrology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Kai Xu
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Dong Sun
- Department of Nephrology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.,Department of Internal Medicine and Diagnostics, Xuzhou Medical University, Xuzhou, China
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20
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Singh AK, Kolligundla LP, Francis J, Pasupulati AK. Detrimental effects of hypoxia on glomerular podocytes. J Physiol Biochem 2021; 77:193-203. [PMID: 33835424 DOI: 10.1007/s13105-021-00788-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 01/11/2021] [Indexed: 12/19/2022]
Abstract
Hypoxia-inducible factor1 (HIF1) plays a pivotal role in ensuring cells adapt to low-oxygen conditions. Depletion of oxygen, a co-substrate during hydroxylation of prolyl (P402 and P564) residues of HIF1⍺, evades HIF1⍺ ubiquitination and enables its dimerization with HIF1β to mediate global transcriptional response to hypoxia. Though HIF1 is largely considered eliciting a protective role during physiological or pathological hypoxia or ischemia, elevated HIF1 during chronic hypoxia contributes to glomerular diseases' pathology and proteinuria. The glomerulus is responsible for renal permselectivity and excretion of ultra-filtrated urine. Podocytes are the glomerulus' major cell types and are instrumental for glomerular filtration, permselectivity, and glomerular basement membrane maintenance. Podocyte injury is expected to impair the efficiency of glomerular filtration and manifestation of glomerulosclerosis and proteinuria. Accumulated evidence suggests that podocytes are susceptible to various insults during chronic hypoxia, including podocyte EMT, slit-diaphragm dysfunction, foot process effacement, and cytoskeletal derangement due to accumulation of HIF1. This review discusses how hypoxia/HIF1 signaling regulates various features and function of podocytes during exposure to chronic hypoxia or inducing HIF1 by various chemical modulators.
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Affiliation(s)
- Ashish K Singh
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Lakshmi P Kolligundla
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Justus Francis
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Anil K Pasupulati
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India.
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21
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Liu L, Ma F, Hao Y, Yi Z, Yu X, Xu B, Wei C, Hu J. Integrative Informatics Analysis of Transcriptome and Identification of Interacted Genes in the Glomeruli and Tubules in CKD. Front Med (Lausanne) 2021; 7:615306. [PMID: 33644086 PMCID: PMC7906987 DOI: 10.3389/fmed.2020.615306] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 12/23/2020] [Indexed: 11/16/2022] Open
Abstract
Chronic kidney disease (CKD) is a complex disease in which the renal function is compromised chronically. Many studies have indicated the crosstalk between the tubule and the glomerulus in CKD progression. However, our understanding of the interaction of tubular and glomerular injury remains incomplete. In this study, we applied a meta-analysis approach on the transcriptome of the tubules and glomeruli of CKD patients to identify differentially expressed genes (DEGs) signature. Functional analysis of pathways and Gene Ontology found that tubular DEGs were mainly involved in cell assembly and remodeling, glomerular DEGs in cell proliferation and apoptosis, and overlapping DEGs mainly in immune response. Correlation analysis was performed to identify the associated DEGs in the tubules and glomeruli. Secreted protein comparison and verification experiments indicated that WFDC2 from the tubule could downregulate PEX19 mRNA and protein levels at the glomeruli in diabetic kidney disease (DKD). This study revealed the distinctive pathways of the tubules and glomeruli and identified interacted genes during CKD progression.
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Affiliation(s)
- Lingyun Liu
- Department of Andrology, The First Hospital of Jilin University, Jilin, China
| | - Fuzhe Ma
- Department of Nephrology, The First Hospital of Jilin University, Jilin, China
| | - Yuanyuan Hao
- Department of Urology, The First Hospital of Jilin University, Jilin, China
| | - Zhengzi Yi
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Xiaoxia Yu
- Division of Nephrology, Affiliated Zhongshan Hospital of Dalian University, Dalian, China
| | - Bo Xu
- Department of Urology, The First Hospital of Jilin University, Jilin, China
| | - Chengguo Wei
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Jinghai Hu
- Department of Urology, The First Hospital of Jilin University, Jilin, China
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22
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Cordella A, Pey P, Dondi F, Dunn M, Caramazza C, Cipone M, Diana A. The ultrasonographic medullary "rim sign" versus medullary "band sign" in cats and their association with renal disease. J Vet Intern Med 2020; 34:1932-1939. [PMID: 32888347 PMCID: PMC7517514 DOI: 10.1111/jvim.15878] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 08/04/2020] [Accepted: 08/12/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Medullary rim sign (MRS) refers to a hyperechoic line in the renal medulla, reported on ultrasound examination (US) in both dogs and cats with and without kidney disease (KD). OBJECTIVE To describe the different aspects of MRS in cats and to assess its association with KD. ANIMALS Cats that underwent US examination, with MRS (study group) with and without KD and without MRS with and without KD (control groups). METHODS Retrospective case-control study: cats with MRS, with or without KD (rim sign groups) and cats without MRS, with or without KD (control groups). Ultrasonographic images were blindly reviewed with attention given to the thickness and margins of the MRS recorded. RESULTS Eighty-four cats with MRS were included and 60 cats recruited for each control group. The MRS had 2 distinct aspects: a thin hyperechoic line with well-defined margins (MRS-line) in 50/84 cats (59%) and a thick hyperechoic band with ill-defined margins (MRS-band) in 34/84 cats (41%). Twenty of 50 (40%) cats with MRS-line and 25/34 (74%) of cats with MRS-band had KD. The frequency of MRS-line was higher in cats without KD, whereas the presence of MRS-band was more frequent in cats with KD (P = .003). CONCLUSIONS AND CLINICAL IMPORTANCE A thick hyperechoic ill-defined band (for which the term medullary band sign is proposed) was more frequently associated with KD, whereas a thin hyperechoic well-defined line (true MRS) may be seen in cats with or without KD.
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Affiliation(s)
- Alessia Cordella
- Department of Veterinary Medical Science, Alma Mater Studiorum, University of Bologna, Ozzano Emilia (BO), Italy
| | - Pascaline Pey
- Department of Veterinary Medical Science, Alma Mater Studiorum, University of Bologna, Ozzano Emilia (BO), Italy
| | - Francesco Dondi
- Department of Veterinary Medical Science, Alma Mater Studiorum, University of Bologna, Ozzano Emilia (BO), Italy
| | - Marilyn Dunn
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Montréal, Saint-Hyacinthe, QC, Canada
| | - Chiara Caramazza
- Department of Veterinary Medical Science, Alma Mater Studiorum, University of Bologna, Ozzano Emilia (BO), Italy
| | - Mario Cipone
- Department of Veterinary Medical Science, Alma Mater Studiorum, University of Bologna, Ozzano Emilia (BO), Italy
| | - Alessia Diana
- Department of Veterinary Medical Science, Alma Mater Studiorum, University of Bologna, Ozzano Emilia (BO), Italy
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23
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Lourenço BN, Coleman AE, Schmiedt CW, Brown CA, Rissi DR, Stanton JB, Giguère S, Berghaus RD, Brown SA, Tarigo JL. Profibrotic gene transcription in renal tissues from cats with ischemia-induced chronic kidney disease. Am J Vet Res 2020; 81:180-189. [PMID: 31985291 DOI: 10.2460/ajvr.81.2.180] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To characterize transcription of profibrotic mediators in renal tissues of cats with ischemia-induced chronic kidney disease (CKD). SAMPLE Banked renal tissues from 6 cats with experimentally induced CKD (RI group) and 8 healthy control cats. PROCEDURES For cats of the RI group, both kidneys were harvested 6 months after ischemia was induced for 90 minutes in 1 kidney. For control cats, the right kidney was evaluated. All kidney specimens were histologically examined for fibrosis, inflammation, and tubular atrophy. Renal tissue homogenates underwent reverse transcription quantitative PCR assay evaluation to characterize gene transcription of hypoxia-inducible factor-1α (HIF-1α), matrix metalloproteinase (MMP)-2, MMP-7, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), transforming growth factor-β1, and vascular endothelial growth factor A. Gene transcription and histologic lesions were compared among ischemic and contralateral kidneys of the RI group and control kidneys. RESULTS Ischemic kidneys had greater transcript levels of MMP-7, MMP-9, and transforming growth factor-β1 relative to control kidneys and of MMP-2 relative to contralateral kidneys. Transcription of TIMP-1 was upregulated and that of vascular endothelial growth factor A was downregulated in ischemic and contralateral kidneys relative to control kidneys. Transcription of HIF-1α did not differ among kidney groups. For ischemic kidneys, there were strong positive correlations between transcription of HIF-1α, MMP-2, MMP-7, and TIMP-1 and severity of fibrosis. CONCLUSIONS AND CLINICAL RELEVANCE Transcription of genes involved in profibrotic pathways remained altered in both kidneys 6 months after transient renal ischemia. This suggested that a single unilateral renal insult can have lasting effects on both kidneys.
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24
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Zhou S, Ai Z, Li W, You P, Wu C, Li L, Hu Y, Ba Y. Deciphering the Pharmacological Mechanisms of Taohe-Chengqi Decoction Extract Against Renal Fibrosis Through Integrating Network Pharmacology and Experimental Validation In Vitro and In Vivo. Front Pharmacol 2020; 11:425. [PMID: 32372953 PMCID: PMC7176980 DOI: 10.3389/fphar.2020.00425] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 03/19/2020] [Indexed: 12/28/2022] Open
Abstract
Taohe-Chengqi decoction (THCQ), a classical traditional Chinese medicinal (TCM) formula, has been extensively used for treating chronic kidney disease (CKD). However, the biological activity and mechanisms of action of its constituents against renal fibrosis have not yet been investigated thoroughly. This study was aimed at devising an integrated strategy for investigating the bioactivity constituents and possible pharmacological mechanisms of the n-butanol extract of THCQ (NE-THCQ) against renal fibrosis. The n-butanol extract of THCQ was prepared by the solvent extraction method. The components of NE-THCQ were analyzed using UPLC-Q/TOF-MS/MS techniques and applied for screening the active components of NE-THCQ according to their oral bioavailability and drug-likeness index. Then, we speculated the potential molecular mechanisms of NE-THCQ against renal fibrosis through pharmacological network analysis. Based on data mining techniques and topological parameters, gene ontology, and pathway enrichment, we established compound-target (C-T), protein-protein interaction (PPI) and compound-target-pathway (C-T-P) networks by Cytoscape to identify the hub targets and pathways. Finally, the potential molecular mechanisms of NE-THCQ against renal fibrosis, as predicted by the network pharmacology analyses, were validated experimentally in renal tubular epithelial cells (HK-2) in vitro and against unilateral ureteral obstruction models in the rat in vivo. We identified 26 components in NE-THCQ and screened seven bioactive ingredients. A total of 118 consensus potential targets associated with renal fibrosis were identified by the network pharmacology approach. The experimental validation results demonstrated that NE-THCQ might inhibit the inflammatory processes, reduce ECM deposition and reverse EMT via PI3K/AKT/mTOR and HIF-1α/VEGF signaling pathways to exert its effect against renal fibrosis. This study identified the potential ingredients of the NE-THCQ by UPLC-Q/TOF-MS/MS and explained the possible mechanisms of NE-THCQ against renal fibrosis by integrating network pharmacology and experimental validation.
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Affiliation(s)
- Shanshan Zhou
- Clinical College of TCM, Hubei University of Chinese Medicine, Wuhan, China
| | - Zhongzhu Ai
- Faculty of Pharmacy, Hubei University of Chinese Medicine, Wuhan, China
| | - Weinan Li
- Nephrology Department, Hubei Provincial Hospital of TCM, Wuhan, China.,Hubei Provincial Academy of Traditional Chinese Medicine, Hubei Provincial Hospital of TCM, Wuhan, China
| | - Pengtao You
- Faculty of Pharmacy, Hubei University of Chinese Medicine, Wuhan, China
| | - Chaoyan Wu
- Traditional Chinese Medicine Department, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Liang Li
- Clinical College of TCM, Hubei University of Chinese Medicine, Wuhan, China
| | - Yuanyang Hu
- Faculty of Pharmacy, Hubei University of Chinese Medicine, Wuhan, China
| | - Yuanming Ba
- Nephrology Department, Hubei Provincial Hospital of TCM, Wuhan, China.,Hubei Provincial Academy of Traditional Chinese Medicine, Hubei Provincial Hospital of TCM, Wuhan, China
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25
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Zhang L, Chen S, Liu Y, Xu X, Zhang Q, Shao S, Wang W, Li X. P-selectin blockade ameliorates lupus nephritis in MRL/lpr mice through improving renal hypoxia and evaluation using BOLD-MRI. J Transl Med 2020; 18:116. [PMID: 32138730 PMCID: PMC7059679 DOI: 10.1186/s12967-020-02284-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/27/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Lupus nephritis is one of the most common and severe complications of systemic lupus erythematosus, of which poor prognosis is indicated by aggravated renal hypoxia and tubulointerstitial fibrosis. Cell adhesion molecules play a key role in the progression of lupus nephritis tubulointerstitial lesion, including P-selectin, which mediates the rolling of leukocytes and subsequent adhesion and infiltration and then initiates the inflammatory immune response and ischemia and hypoxia injury. However, the effects and mechanisms of P-selectin in lupus nephritis remain to be investigated, and a noninvasive measurement of lupus nephritis tubulointerstitial hypoxia and fibrosis remains to be explored. METHODS Thirty-four MRL/lpr mice were randomly divided into the following three groups: MRL/lpr, saline, and anti-P-selectin, which consisted of no treatment, treatment with normal saline, and treatment with anti-P-selectin monoclonal antibody (mAb) from 12 to 16 weeks of age, respectively. Ten male C57BL/6 mice of the same age served as normal controls. 24-h urinary protein, urinary albumin-creatinine ratio, and periodic acid-Schiff were used to assess kidney damage; Western blot or immunohistochemical staining of the hypoxia probe Hypoxyprobe™-1, hypoxia-inducible factor 1α (HIF-1α), and CD31 were used to evaluate hypoxia in renal tissue; and NADPH oxidase subunit gp91phox and p22phox were used to examine renal oxidative stress. The correlation between kidney injury and blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) was calculated to assess the clinical value of BOLD-MRI. RESULTS P-selectin is upregulated in lupus nephritis. Blocking P-selectin with mAb alleviated renal tubulointerstitial fibrosis, renal hypoxia, and peritubular capillary loss, without alteration of the levels of lupus activity indicators, anti-dsDNA antibody, or complement C3. BOLD-MRI showed that the reduced R2* values in the renal cortex and medulla of lupus mice were increased when treated with anti-P-selectin mAb as compared with those treated with normal saline, which were negatively correlated with Hypoxyprobe™-1 hypoxia probe and the expression of HIF-1α. CONCLUSIONS Early intervention of lupus nephritis with anti-P-selectin mAb can significantly improve the hypoxic state of the kidney and reduce the severity of tubulointerstitial lesions. BOLD-MRI techniques are noninvasive and can dynamically evaluate the changes in renal lesions and intrarenal oxygenation levels before and after treatment in lupus nephritis.
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Affiliation(s)
- Liwen Zhang
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Er Road, Shanghai, 200025, People's Republic of China
| | - Sheng Chen
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Yan Liu
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Er Road, Shanghai, 200025, People's Republic of China
| | - Xueqin Xu
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People's Republic of China
| | - Qianying Zhang
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Er Road, Shanghai, 200025, People's Republic of China
| | - Shuxin Shao
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Er Road, Shanghai, 200025, People's Republic of China
| | - Weiming Wang
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Er Road, Shanghai, 200025, People's Republic of China
| | - Xiao Li
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Er Road, Shanghai, 200025, People's Republic of China.
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26
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Edwards A, Palm F, Layton AT. A model of mitochondrial O 2 consumption and ATP generation in rat proximal tubule cells. Am J Physiol Renal Physiol 2020; 318:F248-F259. [PMID: 31790302 PMCID: PMC6985826 DOI: 10.1152/ajprenal.00330.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 11/18/2019] [Accepted: 11/25/2019] [Indexed: 11/22/2022] Open
Abstract
Oxygen tension in the kidney is mostly determined by O2 consumption (Qo2), which is, in turn, closely linked to tubular Na+ reabsorption. The objective of the present study was to develop a model of mitochondrial function in the proximal tubule (PT) cells of the rat renal cortex to gain more insight into the coupling between Qo2, ATP formation (GATP), ATP hydrolysis (QATP), and Na+ transport in the PT. The present model correctly predicts in vitro and in vivo measurements of Qo2, GATP, and ATP and Pi concentrations in PT cells. Our simulations suggest that O2 levels are not rate limiting in the proximal convoluted tubule, absent large metabolic perturbations. The model predicts that the rate of ATP hydrolysis and cytoplasmic pH each substantially regulate the GATP-to-Qo2 ratio, a key determinant of the number of Na+ moles actively reabsorbed per mole of O2 consumed. An isolated increase in QATP or in cytoplasmic pH raises the GATP-to-Qo2 ratio. Thus, variations in Na+ reabsorption and pH along the PT may, per se, generate axial heterogeneities in the efficiency of mitochondrial metabolism and Na+ transport. Our results also indicate that the GATP-to-Qo2 ratio is strongly impacted not only by H+ leak permeability, which reflects mitochondrial uncoupling, but also by K+ leak pathways. Simulations suggest that the negative impact of increased uncoupling in the diabetic kidney on mitochondrial metabolic efficiency is partly counterbalanced by increased rates of Na+ transport and ATP consumption. This model provides a framework to investigate the role of mitochondrial dysfunction in acute and chronic renal diseases.
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Affiliation(s)
- Aurélie Edwards
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Fredrik Palm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Anita T Layton
- Departments of Mathematics, Biomedical Engineering, and Medicine, Duke University, Durham, North Carolina
- Departments of Applied Mathematics and Biology, School of Pharmacy, University of Waterloo, Waterloo, Ontario, Canada
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27
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Aubert V, Kaminski J, Guillaud F, Hauet T, Hannaert P. A Computer Model of Oxygen Dynamics in the Cortex of the Rat Kidney at the Cell-Tissue Level. Int J Mol Sci 2019; 20:E6246. [PMID: 31835730 PMCID: PMC6941061 DOI: 10.3390/ijms20246246] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 12/02/2019] [Accepted: 12/05/2019] [Indexed: 02/06/2023] Open
Abstract
The renal cortex drives renal function. Hypoxia/reoxygenation are primary factors in ischemia-reperfusion (IR) injuries, but renal oxygenation per se is complex and awaits full elucidation. Few mathematical models address this issue: none captures cortical tissue heterogeneity. Using agent-based modeling, we develop the first model of cortical oxygenation at the cell-tissue level (RCM), based on first principles and careful bibliographical analysis. Entirely parameterized with Rat data, RCM is a morphometrically equivalent 2D-slice of cortical tissue, featuring peritubular capillaries (PTC), tubules and interstitium. It implements hemoglobin/O2 binding-release, oxygen diffusion, and consumption, as well as capillary and tubular flows. Inputs are renal blood flow RBF and PO2 feeds; output is average tissue PO2 (tPO2). After verification and sensitivity analysis, RCM was validated at steady-state (tPO2 37.7 ± 2.2 vs. 36.9 ± 6 mmHg) and under transients (ischemic oxygen half-time: 4.5 ± 2.5 vs. 2.3 ± 0.5 s in situ). Simulations confirm that PO2 is largely independent of RBF, except at low values. They suggest that, at least in the proximal tubule, the luminal flow dominantly contributes to oxygen delivery, while the contribution of capillaries increases under partial ischemia. Before addressing IR-induced injuries, upcoming developments include ATP production, adaptation to minutes-hours scale, and segmental and regional specification.
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Affiliation(s)
| | | | | | | | - Patrick Hannaert
- INSERM U1082-IRTOMIT, 86000 Poitiers, France; (V.A.); (J.K.); (F.G.); (T.H.)
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28
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Ogbadu J, Singh G, Aggarwal D. Factors affecting the transition of acute kidney injury to chronic kidney disease: Potential mechanisms and future perspectives. Eur J Pharmacol 2019; 865:172711. [DOI: 10.1016/j.ejphar.2019.172711] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 09/22/2019] [Accepted: 09/30/2019] [Indexed: 12/12/2022]
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29
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Nakuluri K, Nishad R, Mukhi D, Kumar S, Nakka VP, Kolligundla LP, Narne P, Natuva SSK, Phanithi PB, Pasupulati AK. Cerebral ischemia induces TRPC6 via HIF1α/ZEB2 axis in the glomerular podocytes and contributes to proteinuria. Sci Rep 2019; 9:17897. [PMID: 31784544 PMCID: PMC6884642 DOI: 10.1038/s41598-019-52872-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 10/24/2019] [Indexed: 12/14/2022] Open
Abstract
Podocytes are specialized cells of the glomerulus and key component of the glomerular filtration apparatus (GFA). GFA regulates the permselectivity and ultrafiltration of blood. The mechanism by which the integrity of the GFA is compromised and manifest in proteinuria during ischemic stroke remains enigmatic. We investigated the mechanism of ischemic hypoxia-induced proteinuria in a middle cerebral artery occlusion (MCAO) model. Ischemic hypoxia resulted in the accumulation of HIF1α in the podocytes that resulted in the increased expression of ZEB2 (Zinc finger E-box-binding homeobox 2). ZEB2, in turn, induced TRPC6 (transient receptor potential cation channel, subfamily C, member 6), which has increased selectivity for calcium. Elevated expression of TRPC6 elicited increased calcium influx and aberrant activation of focal adhesion kinase (FAK) in podocytes. FAK activation resulted in the stress fibers reorganization and podocyte foot process effacement. Our study suggests overactive HIF1α/ZEB2 axis during ischemic-hypoxia raises intracellular calcium levels via TRPC6 and consequently altered podocyte structure and function thus contributes to proteinuria.
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Affiliation(s)
| | - Rajkishor Nishad
- Department of Biochemistry, University of Hyderabad, Hyderabad, 500046, India
| | - Dhanunjay Mukhi
- Department of Biochemistry, University of Hyderabad, Hyderabad, 500046, India
| | - Sireesh Kumar
- Department of Biotechnology & Bioinformatics, University of Hyderabad, Hyderabad, 500046, India
| | - Venkata P Nakka
- Department of Biochemistry, Acharya Nagarjuna University, Guntur, 522510, India
| | | | - Parimala Narne
- Department of Biotechnology & Bioinformatics, University of Hyderabad, Hyderabad, 500046, India
| | | | - Prakash Babu Phanithi
- Department of Biotechnology & Bioinformatics, University of Hyderabad, Hyderabad, 500046, India.
| | - Anil K Pasupulati
- Department of Biochemistry, University of Hyderabad, Hyderabad, 500046, India.
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30
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Armutcu F, Demircan K, Yildirim U, Namuslu M, Yagmurca M, Celik HT. Hypoxia causes important changes of extracellular matrix biomarkers and ADAMTS proteinases in the adriamycin-induced renal fibrosis model. Nephrology (Carlton) 2019; 24:863-875. [PMID: 30719800 DOI: 10.1111/nep.13572] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2019] [Indexed: 12/12/2022]
Abstract
AIM Renal fibrosis is a common cause of renal dysfunction with chronic kidney diseases. This process is characterized by excessive production of extracellular matrix (ECM) or inhibition of ECM degradation. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) proteinases, which are widely presented in mammals, have very critical roles in ECM remodelling. We aimed to study the role of ADAMTS proteinases and some of the ECM markers in the pathogenesis of renal fibrosis and to investigate the effects of hypoxia on these biomarkers. METHODS In addition to the control group, Adriamycin (ADR) treated rats were divided into four groups as ADR, sham and two hypoxia groups. Renal nephropathy was assessed biochemical assays, pathological and immunohistochemical staining methods. The expression of ADAMTSs and mRNA were determined using Western blotting and real-time PCR, respectively. RESULTS Renal dysfuntion and tissue damage in favour of ECM accumulation and renal fibrosis were observed in the ADR group. This was approved by remarkable changes in the expression of ADAMTS such as increased ADAMTS-1, -12 and -15. In addition, it was found that hypoxia and duration of hypoxia enhanced markers of tubulointerstitial fibrosis in the rat kidney tissues. Also, expression differences especially in ADAMTS-1, -6 and -15 were observed in the hypoxia groups. The variable and different expression patterns of ADAMTS proteinases in the ADR-induced renal fibrosis suggest that ADAMTS family members are involved in the development and progression of fibrosis. CONCLUSION The expression changes of ADAMTS proteinases in kidney and association with hypoxia have potential clues to contribute to the early diagnosis and treatment options of renal fibrosis.
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Affiliation(s)
- Ferah Armutcu
- Department of Biochemistry, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey
| | - Kadir Demircan
- Department of Medical Biology, Turgut Ozal University, Faculty of Medicine, Ankara, Turkey
| | - Umran Yildirim
- Department of Pathology, Turgut Ozal University, Faculty of Medicine, Ankara, Turkey
| | - Mehmet Namuslu
- Department of Biochemistry, Turgut Ozal University, Faculty of Medicine, Ankara, Turkey
| | - Murat Yagmurca
- Health Sciences University, Higher Specialization Training and Research Hospital, Histology and Embryology Clinic, Bursa, Turkey
| | - Hüseyin T Celik
- Department of Biochemistry, Turgut Ozal University, Faculty of Medicine, Ankara, Turkey
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31
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Wewers TM, Mayer AB, Pfleiderer A, Beul K, Schmidt R, Heitplatz B, Van Marck V, Nolte I, Pavenstädt H, Reuter S, Brand M, Di Marco GS. Increased soluble fms-like tyrosine kinase 1 after ischemia reperfusion contributes to adverse clinical outcomes following kidney transplantation. Kidney Int 2019; 95:1091-1102. [PMID: 30824181 DOI: 10.1016/j.kint.2018.11.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 10/05/2018] [Accepted: 11/02/2018] [Indexed: 12/20/2022]
Abstract
Renal ischemia reperfusion injury (IRI) adversely affects clinical outcomes following kidney transplantation. Understanding the cellular mechanisms and the changes in gene/protein expression following IRI may help to improve these outcomes. Serum soluble fms-like tyrosine kinase 1 (sFlt-1), a circulating antiangiogenic protein, is increased in the first week following kidney transplantation. We evaluated the casual relationship of elevated sFlt-1 levels with renal microvascular dysfunction following IRI in a longitudinal study of 93 kidney transplant recipients and in several animal models. Transplant recipients with higher sFlt-1 levels had higher odds of delayed graft function, graft rejection, impaired graft function, and death. In a subgroup of 25 participants who underwent kidney biopsy within 4 months of kidney transplantation, peritubular capillary area was lower in those with elevated serum sFtl-1 levels. The administration of recombinant sFlt-1 into rodents resulted in significant structural and functional changes of the renal microvasculature, including reduced peritubular capillary density and intracapillary blood volume, and lead to increased expression of inflammatory genes and increased fibrosis. In a murine model of IRI, the kidney was a site of sFlt-1 production, and systemic neutralization of sFlt-1 preserved peritubular capillary density and alleviated renal fibrosis. Our data indicate that high sFlt-1 levels after IRI play an important role in the pathogenesis of microvascular dysfunction, thereby contributing to adverse clinical outcomes following kidney transplantation.
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Affiliation(s)
- Theresa M Wewers
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany; Small Animal Hospital, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Anna B Mayer
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany
| | - Alexander Pfleiderer
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany
| | - Katrin Beul
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany
| | - Rene Schmidt
- Institute for Biostatistics and Clinical Research, University Hospital Münster, Münster, Germany
| | - Barbara Heitplatz
- Department of Pathology, University Hospital Münster, Münster, Germany
| | - Veerle Van Marck
- Department of Pathology, University Hospital Münster, Münster, Germany
| | - Ingo Nolte
- Small Animal Hospital, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Hermann Pavenstädt
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany
| | - Stefan Reuter
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany
| | - Marcus Brand
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany
| | - Giovana S Di Marco
- Department of Internal Medicine D, University Hospital Münster, Münster, Germany.
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Application of BOLD-MRI in the classification of renal function in chronic kidney disease. Abdom Radiol (NY) 2019; 44:604-611. [PMID: 30151714 DOI: 10.1007/s00261-018-1750-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PURPOSE The purpose of the study was to explore the application of blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-MRI) in classification of chronic kidney disease (CKD). METHODS Twenty-nine cases with CKD and 27 healthy volunteers underwent renal BOLD-MRI. Cases of CKD were divided into two groups according to the estimated glomerular filtration rate (eGFR). The R2* values were measured in renal cortex and medulla, respectively. The difference of R2* between renal cortex and medulla was compared, and the correlations of R2* value in renal cortex and medulla with eGFR were analyzed. RESULTS Twenty-nine cases of CKD were divided into two groups, with 13 cases of mild renal impairment and 16 cases of moderate to severe renal impairment. In the control and mild renal impairment group, the R2* of renal cortex was significantly lower than that of medulla (P < 0.001). In the control group, mild renal impairment and moderate to severe renal impairment group, the R2* value of cortex increased, while the R2* value of medulla gradually decreased. The eGFR of patients was positively correlated with R2* of medulla (r = 0.81, P < 0.001), while displayed no correlation with R2* of cortex (r = - 0.32, P > 0.05). When the threshold of R2* of medulla was set at 28.4 Hz, the sensitivity and specificity to distinguish normal and mild renal impairment group were 92.31% and 85.19%, respectively. CONCLUSION The change of blood oxygen in renal cortex and medulla could be detected with BOLD-MRI, so as to evaluate the renal function and anoxic injury of CKD.
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Christensen M, Schiffer TA, Gustafsson H, Krag SP, Nørregaard R, Palm F. Metformin attenuates renal medullary hypoxia in diabetic nephropathy through inhibition uncoupling protein-2. Diabetes Metab Res Rev 2019; 35:e3091. [PMID: 30345618 DOI: 10.1002/dmrr.3091] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 10/03/2018] [Accepted: 10/16/2018] [Indexed: 11/09/2022]
Abstract
BACKGROUND The purpose of the study is to examine the effect of metformin on oxygen metabolism and mitochondrial function in the kidney of an animal model of insulinopenic diabetes in order to isolate any renoprotective effect from any concomitant effect on blood glucose homeostasis. METHODS Sprague-Dawley rats were injected with streptozotocin (STZ) (50 mg kg-1 ) and when stable started on metformin treatment (250 mg kg-1 ) in the drinking water. Rats were prepared for in vivo measurements 25 to 30 days after STZ injection, where renal function, including glomerular filtration rate and sodium transport, was estimated in anesthetized rats. Intrarenal oxygen tension was measured using oxygen sensors. Furthermore, mitochondrial function was assessed in mitochondria isolated from kidney cortex and medulla analysed by high-resolution respirometry, and superoxide production was evaluated using electron paramagnetic resonance. RESULTS Insulinopenic rats chronically treated with metformin for 4 weeks displayed improved medullary tissue oxygen tension despite of no effect of metformin on blood glucose homeostasis. Metformin reduced UCP2-dependent LEAK and differentially affected medullary mitochondrial superoxide radical production in control and diabetic rats. CONCLUSIONS Metformin attenuates diabetes-induced renal medullary tissue hypoxia in an animal model of insulinopenic type 1 diabetes. The results suggest that the mechanistic pathway to attenuate the diabetes-induced medullary hypoxia is independent of blood glucose homeostasis and includes reduced UCP2-mediated mitochondrial proton LEAK.
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Affiliation(s)
| | - Tomas A Schiffer
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Håkan Gustafsson
- Department of Radiology Norrköping and Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | | | - Rikke Nørregaard
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Fredrik Palm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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Pletz J, Enoch SJ, Jais DM, Mellor CL, Pawar G, Firman JW, Madden JC, Webb SD, Tagliati CA, Cronin MTD. A critical review of adverse effects to the kidney: mechanisms, data sources, and in silico tools to assist prediction. Expert Opin Drug Metab Toxicol 2018; 14:1225-1253. [PMID: 30345815 DOI: 10.1080/17425255.2018.1539076] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION The kidney is a major target for toxicity elicited by pharmaceuticals and environmental pollutants. Standard testing which often does not investigate underlying mechanisms has proven not to be an adequate hazard assessment approach. As such, there is an opportunity for the application of computational approaches that utilize multiscale data based on the Adverse Outcome Pathway (AOP) paradigm, coupled with an understanding of the chemistry underpinning the molecular initiating event (MIE) to provide a deep understanding of how structural fragments of molecules relate to specific mechanisms of nephrotoxicity. Aims covered: The aim of this investigation was to review the current scientific landscape related to computational methods, including mechanistic data, AOPs, publicly available knowledge bases and current in silico models, for the assessment of pharmaceuticals and other chemicals with regard to their potential to elicit nephrotoxicity. A list of over 250 nephrotoxicants enriched with, where possible, mechanistic and AOP-derived understanding was compiled. Expert opinion: Whilst little mechanistic evidence has been translated into AOPs, this review identified a number of data sources of in vitro, in vivo, and human data that may assist in the development of in silico models which in turn may shed light on the interrelationships between nephrotoxicity mechanisms.
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Affiliation(s)
- Julia Pletz
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - Steven J Enoch
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - Diviya M Jais
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - Claire L Mellor
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - Gopal Pawar
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - James W Firman
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - Judith C Madden
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
| | - Steven D Webb
- b Department of Applied Mathematics , Liverpool John Moores University , Liverpool , UK
| | - Carlos A Tagliati
- c Departamento de Análises Clínicas e Toxicológicas , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Mark T D Cronin
- a School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
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Nakuluri K, Mukhi D, Nishad R, Saleem MA, Mungamuri SK, Menon RK, Pasupulati AK. Hypoxia induces ZEB2 in podocytes: Implications in the pathogenesis of proteinuria. J Cell Physiol 2018; 234:6503-6518. [DOI: 10.1002/jcp.27387] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 08/17/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Krishnamurthy Nakuluri
- Department of Biochemistry School of Life Sciences, University of Hyderabad Hyderabad India
| | - Dhanunjay Mukhi
- Department of Biochemistry School of Life Sciences, University of Hyderabad Hyderabad India
| | - Rajkishor Nishad
- Department of Biochemistry School of Life Sciences, University of Hyderabad Hyderabad India
| | | | - Sathish Kumar Mungamuri
- Institute of Basic Sciences and Translational Research, Asian Health Care Foundation, Asian Institute of Gastroenterology Hyderabad India
| | - Ram K. Menon
- Department of Pediatrics University of Michigan Ann Arbor Michigan
- Department of Molecular and Integrative Physiology University of Michigan Ann Arbor Michigan
| | - Anil Kumar Pasupulati
- Department of Biochemistry School of Life Sciences, University of Hyderabad Hyderabad India
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Lannemyr L, Ricksten S, Rundqvist B, Andersson B, Bartfay S, Ljungman C, Dahlberg P, Bergh N, Hjalmarsson C, Gilljam T, Bollano E, Karason K. Differential Effects of Levosimendan and Dobutamine on Glomerular Filtration Rate in Patients With Heart Failure and Renal Impairment:A Randomized Double-Blind Controlled Trial. J Am Heart Assoc 2018; 7:e008455. [PMID: 30369310 PMCID: PMC6201411 DOI: 10.1161/jaha.117.008455] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 07/02/2018] [Indexed: 01/07/2023]
Abstract
Background The management of the cardiorenal syndrome in advanced heart failure is challenging, and the role of inotropic drugs has not been fully defined. Our aim was to compare the renal effects of levosimendan versus dobutamine in patients with heart failure and renal impairment. Methods and Results In a randomized double-blind study, we assigned patients with chronic heart failure (left ventricular ejection fraction <40%) and impaired renal function (glomerular filtration rate <80 mL/min per 1.73 m2) to receive either levosimendan (loading dose 12 μg/kg+0.1 μg/kg per minute) or dobutamine (7.5 μg/kg per minute) for 75 minutes. A pulmonary artery catheter was used for measurements of systemic hemodynamics, and a renal vein catheter was used to measure renal plasma flow by the infusion clearance technique for PAH (para-aminohippurate) corrected by renal extraction of PAH . Filtration fraction was measured by renal extraction of chromium ethylenediamine tetraacetic acid. A total of 32 patients completed the study. Following treatment, the levosimendan and dobutamine groups displayed similar increases in renal blood flow (22% and 26%, respectively) with no significant differences between groups. Glomerular filtration rate increased by 22% in the levosimendan group but remained unchanged in the dobutamine group ( P=0.012). Filtration fraction was not affected by levosimendan but decreased by 17% with dobutamine ( P=0.045). Conclusions In patients with chronic heart failure and renal impairment, levosimendan increases glomerular filtration rate to a greater extent than dobutamine and thus may be the preferred inotropic agent for treating patients with the cardiorenal syndrome. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT 02133105.
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Affiliation(s)
- Lukas Lannemyr
- Department of Anesthesiology and Intensive Care MedicineUniversity of GothenburgSahlgrenska UniversityGothenburgSweden
| | - Sven‐Erik Ricksten
- Department of Anesthesiology and Intensive Care MedicineUniversity of GothenburgSahlgrenska UniversityGothenburgSweden
| | - Bengt Rundqvist
- Department of TransplantationSahlgrenska University HospitalGothenburgSweden
| | - Bert Andersson
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Sven‐Erik Bartfay
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | | | - Pia Dahlberg
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Niklas Bergh
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Clara Hjalmarsson
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Thomas Gilljam
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Entela Bollano
- Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Kristjan Karason
- Department of TransplantationSahlgrenska University HospitalGothenburgSweden
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Chhabra V, Anand AS, Baidya AK, Malik SM, Kohli E, Reddy MPK. Hypobaric hypoxia induced renal damage is mediated by altering redox pathway. PLoS One 2018; 13:e0195701. [PMID: 30005088 PMCID: PMC6044529 DOI: 10.1371/journal.pone.0195701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 03/28/2018] [Indexed: 12/29/2022] Open
Abstract
Systemic hypobaric hypoxia is reported to cause renal damage; nevertheless the exact pathophysiological mechanisms are not completely understood. Therefore, the present study aims to explore renal pathophysiology by using proteomics approach under hypobaric hypoxia. Six to eight week old male Sprague Dawley rats were exposed to hypobaric hypoxia equivalent to altitude of 7628 metres (pO2-282mmhg) at 28°C and 55% humidity in decompression chamber for different time intervals; 1, 3, and7 days. Various physiological, proteomic and bioinformatic studies were carried out to examine the effect of chronic hypobaric hypoxia on kidney. Our data demonstrated mild to moderate degenerative tubular changes, altered renal function, injury biomarkers and systolic blood pressure with increase in duration of hypobaric hypoxia exposure. Renal proteomic analysis showed 38 differential expressed spots, out of which 25 spots were down regulated and 13 were up regulated in 7 dayhypobarichypoxic exposure group of rats as compared to normoxia control. Identified proteins were involved in specific molecular changes pertinent to endogenous redox pathways, cellular integrity and energy metabolism. The study provides an empirical evidence of renal homeostasis under hypobaric hypoxia by investigating both physiological and proteomics changes. The identification of explicit key proteins provides a valuable clue about redox signalling mediated renal damage under hypobaric hypoxia.
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Affiliation(s)
- Varun Chhabra
- Cardio-Respiratory Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organisation (DRDO), Ministry of Defence, Timarpur, Delhi, India
| | - Avnika Singh Anand
- Neurobiology Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organisation (DRDO), Ministry of Defence, Timarpur, Delhi, India
| | - Amit Kumar Baidya
- Cardio-Respiratory Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organisation (DRDO), Ministry of Defence, Timarpur, Delhi, India
| | - Shajer Manzoor Malik
- Cardio-Respiratory Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organisation (DRDO), Ministry of Defence, Timarpur, Delhi, India
| | - Ekta Kohli
- Neurobiology Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organisation (DRDO), Ministry of Defence, Timarpur, Delhi, India
| | - Maramreddy Prasanna Kumar Reddy
- Cardio-Respiratory Division, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organisation (DRDO), Ministry of Defence, Timarpur, Delhi, India
- * E-mail: ,
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Liu H, Zhou Z, Li X, Li C, Wang R, Zhang Y, Niu G. Diffusion-weighted imaging for staging chronic kidney disease: a meta-analysis. Br J Radiol 2018; 91:20170952. [PMID: 29888970 PMCID: PMC6475960 DOI: 10.1259/bjr.20170952] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Objective: To evaluate stages of chronic kidney disease (CKD) by apparent diffusion coefficient (ADC) obtained from diffusion weighted imaging (DWI) using a meta-analysis. Methods: Literature databases were searched from PubMed, Web of Science, Cochrane and Embase to identify relevant articles about DWI in CKD between 1999 and 2017. ADC values were extracted from the healthy group and CKD patients with different stages. Meta-analysis was conducted using STATA v. 12.0. A random-effects model was performed to acquire the effect estimate, which was expressed as a pooled weighted mean difference (WMD) with 95% confidence interval (CI). We performed comparisons of ADC values between the following groups: (1) the ADC values of the normal kidneys vs earlier Stage 1–2 of CKD; (2) Stage 3 vs the Stage 1–2 of CKD; (3) the Stage 4–5 vs the Stage 3. Results: Six studies were included in this meta-analysis. The CKD patients with earlier Stage 1–2 showed lower ADC values than the healthy subjects [WMD = −0.09, 95% CI(−0.12 to −0.06), p < 0.001]. However, no obvious difference in ADC values was found between the Stage 3 and Stage1–2 of CKD [WMD = −0.09, 95% CI (−0.18 to 0.01), p = 0.08]. The CKD Stage3 had higher ADC values than those of Stage4–5 [WMD = −0.21, 95% CI (−0.32 to −0.11), p = 0.01]. Conclusion: DWI is an accurate and non-invasive imaging technique for early diagnosis and staging of CKD. Quantitative DWI may potentially play a role in making clinical decisions in the follow-up of CKD. Advances in knowledge DWI can be a valuable tool for staging of CKD.
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Affiliation(s)
- Haitian Liu
- 1 Department of Diagnostic Radiology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
| | - Zhangjian Zhou
- 2 Department of Surgical Oncology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
| | - Xiang Li
- 1 Department of Diagnostic Radiology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
| | - Chenxia Li
- 1 Department of Diagnostic Radiology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
| | - Rong Wang
- 1 Department of Diagnostic Radiology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
| | - Yuelang Zhang
- 1 Department of Diagnostic Radiology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
| | - Gang Niu
- 1 Department of Diagnostic Radiology, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi Province , China
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Renal Blood Flow, Glomerular Filtration Rate, and Renal Oxygenation in Early Clinical Septic Shock*. Crit Care Med 2018. [DOI: 10.1097/ccm.0000000000003088] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Gong L, Jiang L, Qin Y, Jiang X, Song K, Yu X. Protective effect of retinoic acid receptor α on hypoxia-induced epithelial to mesenchymal transition of renal tubular epithelial cells associated with TGF-β/MMP-9 pathway. Cell Biol Int 2018; 42:1050-1059. [PMID: 29719094 DOI: 10.1002/cbin.10982] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 04/28/2018] [Indexed: 12/12/2022]
Abstract
Retinoic acid receptor α (RARα), a member of family of the nuclear retinoic acid receptors (RARs), plays an essential role in various chronic kidney diseases (CKD). Renal tubular epithelial to mesenchymal transition (EMT) is a common mechanism of progression of renal interstitial fibrosis (RIF). Hypoxia has been extensively considered as one of major inducers of renal tubular EMT. However, the effects of RARα on hypoxia-induced EMT have not yet been described so far. The aim of the present study was to explore the roles and potential mechanisms of RARα in hypoxia-induced EMT of renal tubular epithelial cells (RTECs). Our results showed that expression of RARα in RTECs subjected to hypoxia significantly was reduced, accompanied by decreased expression level of the epithelial marker E-cadherin, and increased expression levels of the mesenchymal markers α-smooth muscle actin (α-SMA) and vimentin, in accord with EMT. Meanwhile, hypoxia could cause RTECs to obviously express TGF-β and matrix metalloproteinase-9 (MMP-9). Furthermore, using lentivirus-based delivery vectors to overexpress RARα in RTECs, we demonstrated that RARα alleviated hypoxia-induced EMT of RTECs and downregulated the expression levels of TGF-β and MMP-9. In a word, RARα protects RTECs against EMT induced by hypoxia associated with TGF-β/MMP-9 pathway.
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Affiliation(s)
- Ling Gong
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China
| | - Ling Jiang
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China
| | - Yuanhan Qin
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China
| | - Xingbo Jiang
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China
| | - Kunling Song
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China
| | - Xueyun Yu
- Department of Pediatrics, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China
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Changes in Renal Peritubular Capillaries in Canine and Feline Chronic Kidney Disease. J Comp Pathol 2018; 160:79-83. [DOI: 10.1016/j.jcpa.2018.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 03/19/2018] [Accepted: 03/24/2018] [Indexed: 02/01/2023]
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Abuyassin B, Badran M, Ayas NT, Laher I. Intermittent hypoxia causes histological kidney damage and increases growth factor expression in a mouse model of obstructive sleep apnea. PLoS One 2018; 13:e0192084. [PMID: 29389945 PMCID: PMC5794148 DOI: 10.1371/journal.pone.0192084] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 01/16/2018] [Indexed: 01/01/2023] Open
Abstract
Epidemiological studies demonstrate an association between obstructive sleep apnea (OSA) and accelerated loss of kidney function. It is unclear whether the decline in function is due to OSA per se or to other confounding factors such as obesity. In addition, the structural kidney abnormalities associated with OSA are unclear. The objective of this study was to determine whether intermittent hypoxia (IH), a key pathological feature of OSA, induces renal histopathological damage using a mouse model. Ten 8-week old wild-type male CB57BL/6 mice were randomly assigned to receive either IH or intermittent air (IA) for 60 days. After euthanasia, one kidney per animal was paraformaldehyde-fixed and then sectioned for histopathological and immunohistochemical analysis. Measurements of glomerular hypertrophy and mesangial matrix expansion were made in periodic acid–Schiff stained kidney sections, while glomerular transforming growth factor-β1 (TGF-β1), connective tissue growth factor (CTGF) and vascular endothelial growth factor-A (VEGF-A) proteins were semi-quantified by immunohistochemistry. The antigen-antibody reaction was detected by 3,3′-diaminobenzidine chromogen where the color intensity semi-quantified glomerular protein expression. To enhance the accuracy of protein semi-quantification, the percentage of only highly-positive staining was used for analysis. Levels of TGF-β, CTGF and VEGF-A proteins in the kidney cortex were further quantified by western blotting. Cellular apoptosis was also investigated by measuring cortical antiapoptotic B-cell lymphoma 2 (Bcl-2) and apoptotic Bcl-2-associated X (Bax) proteins by western blotting. Further investigation of cellular apoptosis was carried out by fluorometric terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) staining. Finally, the levels of serum creatinine and 24-hour urinary albumin were measured as a general index of renal function. Our results indicate that mice exposed to IH have an increased glomerular area (by 1.13 fold, p< 0.001) and expansion of mesangial matrix (by 1.8 fold, p< 0.01). Moreover, the glomerular expressions of TGF-β1, CTGF and VEGF-A proteins were 2.7, 2.2 and 3.8-fold higher in mice exposed to IH (p< 0.05 for all). Furthermore, western blotting protein analysis demonstrates that IH-exposed mice express higher levels of TGF-β1, CTGF and VEGF-A proteins by 1.9, 4.0 and 1.6-fold (p< 0.05 for all) respectively. Renal cellular apoptosis was greater in the IH group as shown by an increased cortical Bax/Bcl-2 protein ratio (p< 0.01) and higher fluorometric TUNEL staining (p< 0.001). Finally, 24-hr urinary albumin levels were higher in mice exposed to IH (43.4 μg vs 9.7 μg, p< 0.01), while there were no differences in serum creatinine levels between the two groups. We conclude that IH causes kidney injury that is accompanied by glomerular hypertrophy, mesangial matrix expansion, increased expression of glomerular growth factors and an increased cellular apoptosis.
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Affiliation(s)
- Bisher Abuyassin
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Mohammad Badran
- Departments of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Najib T. Ayas
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Ismail Laher
- Departments of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
- * E-mail:
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Conway BN, Badders AN, Costacou T, Arthur JM, Innes KE. Perfluoroalkyl substances and kidney function in chronic kidney disease, anemia, and diabetes. Diabetes Metab Syndr Obes 2018; 11:707-716. [PMID: 30532572 PMCID: PMC6244585 DOI: 10.2147/dmso.s173809] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Anemia often complicates chronic kidney disease (CKD), leading to insufficient tissue oxygenation and hypoxic injury, the factor thought to underlie progression from CKD to renal failure. Perfluorocarbons are potent oxygen transporters used in organ preservation and synthetic blood development. Data are scarce on their relationship with kidney function, especially in diabetes where anemia and hypoxia are more prevalent. We investigated the relationship of perfluoroalkyl acids (PFAS) with kidney function and variation by diabetes and anemia status. METHODS Data on 53,650 adults (5,210 with diabetes) were obtained from the C8 Health Project. CKD was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Four PFAS were investigated: perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid, perfluorooctane sulfonate, and perfluorononanoic acid. FINDINGS Each PFAS was positively associated with eGFR among those with CKD or anemia; this was the strongest among those with both CKD and anemia, followed by those with CKD uncomplicated by anemia. These relationships were more pronounced among those with diabetes (all P<0.01). In the absence of both CKD and anemia, PFAS was inversely associated with eGFR. Among persons with both anemia and diabetes, when further stratified by CKD stage, compared to an eGFR <30, ORs (95% CI) for being in the eGFR ≥ 90, 60-89, 45-59, and 30-45 range, respectively, were 3.20 (2.00-5.13), 2.64 (1.83-3.80), 3.18 (2.17-4.67), and 1.99 (1.38-2.86) for each ng/dL increase in PFHxS. Results were similar for each PFAS. INTERPRETATION PFAS are inversely associated with kidney function in CKD and diabetes, with a stronger relation observed when anemia is present.
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Affiliation(s)
- Baqiyyah N Conway
- Department of Epidemiology, School of Public Health, West Virginia University, Morgantown, WV, USA,
- Department of Community Health, School of Rural and Community Health, University of Texas Health Science Center at Tyler, Tyler, TX, USA,
| | - Ashley N Badders
- Department of Epidemiology, School of Public Health, West Virginia University, Morgantown, WV, USA,
- Department of Biostatistics, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tina Costacou
- Department of Epidemiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - John M Arthur
- Department of Internal Medicine, Division of Nephrology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Kim E Innes
- Department of Epidemiology, School of Public Health, West Virginia University, Morgantown, WV, USA,
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Hultström M, Becirovic-Agic M, Jönsson S. Comparison of acute kidney injury of different etiology reveals in-common mechanisms of tissue damage. Physiol Genomics 2017; 50:127-141. [PMID: 29341864 DOI: 10.1152/physiolgenomics.00037.2017] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Acute kidney injury (AKI) is a syndrome of reduced glomerular filtration rate and urine production caused by a number of different diseases. It is associated with renal tissue damage. This tissue damage can cause tubular atrophy and interstitial fibrosis that leads to nephron loss and progression of chronic kidney disease (CKD). This review describes the in-common mechanisms behind tissue damage in AKI caused by different underlying diseases. Comparing six high-quality microarray studies of renal gene expression after AKI in disease models (gram-negative sepsis, gram-positive sepsis, ischemia-reperfusion, malignant hypertension, rhabdomyolysis, and cisplatin toxicity) identified 5,254 differentially expressed genes in at least one of the AKI models; 66% of genes were found only in one model, showing that there are unique features to AKI depending on the underlying disease. There were in-common features in the form of four genes that were differentially expressed in all six models, 49 in at least five, and 215 were found in common between at least four models. Gene ontology enrichment analysis could be broadly categorized into the injurious processes hypoxia, oxidative stress, and inflammation, as well as the cellular outcomes of cell death and tissue remodeling in the form of epithelial-to-mesenchymal transition. Pathway analysis showed that MYC is a central connection in the network of activated genes in-common to AKI, which suggests that it may be a central regulator of renal gene expression in tissue injury during AKI. The outlining of this molecular network may be useful for understanding progression from AKI to CKD.
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Affiliation(s)
- Michael Hultström
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University , Uppsala , Sweden.,Anaesthesia and Intensive Care Medicine, Department of Surgical Sciences, Uppsala University , Uppsala , Sweden
| | - Mediha Becirovic-Agic
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University , Uppsala , Sweden
| | - Sofia Jönsson
- Integrative Physiology, Department of Medical Cell Biology, Uppsala University , Uppsala , Sweden
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45
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Lee CJ, Ngo JP, Kar S, Gardiner BS, Evans RG, Smith DW. A pseudo-three-dimensional model for quantification of oxygen diffusion from preglomerular arteries to renal tissue and renal venous blood. Am J Physiol Renal Physiol 2017; 313:F237-F253. [DOI: 10.1152/ajprenal.00659.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/24/2017] [Accepted: 04/02/2017] [Indexed: 01/13/2023] Open
Abstract
To assess the physiological significance of arterial-to-venous (AV) oxygen shunting, we generated a new pseudo-three-dimensional computational model of oxygen diffusion from intrarenal arteries to cortical tissue and veins. The model combines the 11 branching levels (known as “Strahler” orders) of the preglomerular renal vasculature in the rat, with an analysis of an extensive data set obtained using light microscopy to estimate oxygen mass transfer coefficients for each Strahler order. Furthermore, the AV shunting model is now set within a global oxygen transport model that includes transport from arteries, glomeruli, peritubular capillaries, and veins to tissue. While a number of lines of evidence suggest AV shunting is significant, most importantly, our AV oxygen shunting model predicts AV shunting is small under normal physiological conditions (~0.9% of total renal oxygen delivery; range 0.4–1.4%), but increases during renal ischemia, glomerular hyperfiltration (~2.1% of total renal oxygen delivery; range 0.84–3.36%), and some cardiovascular disease states (~3.0% of total renal oxygen delivery; range 1.2–4.8%). Under normal physiological conditions, blood Po2 is predicted to fall by ~16 mmHg from the root of the renal artery to glomerular entry, with AV oxygen shunting contributing ~40% and oxygen diffusion from arteries to tissue contributing ~60% of this decline. Arterial Po2 is predicted to fall most rapidly from Strahler order 4, under normal physiological conditions. We conclude that AV oxygen shunting normally has only a small impact on renal oxygenation, but may exacerbate renal hypoxia during renal ischemia, hyperfiltration, and some cardiovascular disease states.
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Affiliation(s)
- Chang-Joon Lee
- Faculty of Engineering and Mathematical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Jennifer P. Ngo
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Sydney, Australia; and
| | - Saptarshi Kar
- Faculty of Engineering and Mathematical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Bruce S. Gardiner
- School of Engineering and Information Technology, Murdoch University, Perth, Western Australia, Australia
| | - Roger G. Evans
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Sydney, Australia; and
| | - David W. Smith
- Faculty of Engineering and Mathematical Sciences, The University of Western Australia, Perth, Western Australia, Australia
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46
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Lee CJ, Gardiner BS, Ngo JP, Kar S, Evans RG, Smith DW. Accounting for oxygen in the renal cortex: a computational study of factors that predispose the cortex to hypoxia. Am J Physiol Renal Physiol 2017; 313:F218-F236. [DOI: 10.1152/ajprenal.00657.2016] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/24/2017] [Accepted: 04/05/2017] [Indexed: 12/21/2022] Open
Abstract
We develop a pseudo-three-dimensional model of oxygen transport for the renal cortex of the rat, incorporating both the axial and radial geometry of the preglomerular circulation and quantitative information regarding the surface areas and transport from the vasculature and renal corpuscles. The computational model was validated by simulating four sets of published experimental studies of renal oxygenation in rats. Under the control conditions, the predicted cortical tissue oxygen tension ([Formula: see text]) or microvascular oxygen tension (µPo2) were within ±1 SE of the mean value observed experimentally. The predicted [Formula: see text] or µPo2 in response to ischemia-reperfusion injury, acute hemodilution, blockade of nitric oxide synthase, or uncoupling mitochondrial respiration, were within ±2 SE observed experimentally. We performed a sensitivity analysis of the key model parameters to assess their individual or combined impact on the predicted [Formula: see text] and µPo2. The model parameters analyzed were as follows: 1) the major determinants of renal oxygen delivery ([Formula: see text]) (arterial blood Po2, hemoglobin concentration, and renal blood flow); 2) the major determinants of renal oxygen consumption (V̇o2) [glomerular filtration rate (GFR) and the efficiency of oxygen utilization for sodium reabsorption (β)]; and 3) peritubular capillary surface area (PCSA). Reductions in PCSA by 50% were found to profoundly increase the sensitivity of [Formula: see text] and µPo2 to the major the determinants of [Formula: see text] and V̇o2. The increasing likelihood of hypoxia with decreasing PCSA provides a potential explanation for the increased risk of acute kidney injury in some experimental animals and for patients with chronic kidney disease.
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Affiliation(s)
- Chang-Joon Lee
- Faculty of Engineering and Mathematical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Bruce S. Gardiner
- School of Engineering and Information Technology, Murdoch University, Perth, Western Australia, Australia; and
| | - Jennifer P. Ngo
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Sydney, Australia
| | - Saptarshi Kar
- Faculty of Engineering and Mathematical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Roger G. Evans
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Sydney, Australia
| | - David W. Smith
- Faculty of Engineering and Mathematical Sciences, The University of Western Australia, Perth, Western Australia, Australia
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47
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Tubulointerstitial fibrosis can sensitize the kidney to subsequent glomerular injury. Kidney Int 2017; 92:1395-1403. [PMID: 28709637 DOI: 10.1016/j.kint.2017.04.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 03/21/2017] [Accepted: 04/06/2017] [Indexed: 01/24/2023]
Abstract
Chronic glomerular injury is associated with eventual development of tubulointerstitial fibrosis. Here we aimed to assess whether, and how, mild chronic tubulointerstitial injury affects glomeruli. For this, we generated mice expressing different toxin receptors, one on their proximal tubular epithelial cells (diphtheria toxin receptor [DTR]) and the other only on podocytes (human CD25 [IL-2R] driven by the nephrin promoter [Nep25]), allowing serial induction of tubule-specific and glomerular (podocyte)-specific injury, respectively. Six weeks after diphtheria toxin injection, mild interstitial fibrosis was found in Nep25+/DTR+, but not in Nep25+/DTR- mice. However, atubular glomeruli and neuronal nitric oxide synthase, a mediator of tubuloglomerular feedback, were higher in Nep25+/DTR+ than in DTR- mice and these atubular glomeruli had less podocyte density as assessed by WT-1 biomarker expression. Peritubular capillary density, hypoxia-inducible factor-1 and -2, and cyclooxygenase 2 expression were similar at week six in the two groups. At week seven, all mice were given the immunotoxin LMB-2, which binds to CD25 to induce podocyte injury. Ten days later, proteinuria, podocyte injury, and glomerulosclerosis were more severe in Nep25+/DTR+ than Nep25+/DTR- mice with more severe sclerosis in the tubule-connected glomeruli. This supports the concept that even mild preexisting tubulointerstitial injury sensitizes glomeruli to subsequent podocyte-specific injury. Thus, increased atubular glomeruli and abnormal tubuloglomerular feedback significantly contribute to the crosstalk between the tubulointerstitium and glomeruli.
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48
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Liu ZZ, Bullen A, Li Y, Singh P. Renal Oxygenation in the Pathophysiology of Chronic Kidney Disease. Front Physiol 2017; 8:385. [PMID: 28701959 PMCID: PMC5487476 DOI: 10.3389/fphys.2017.00385] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 05/23/2017] [Indexed: 12/19/2022] Open
Abstract
Chronic kidney disease (CKD) is a significant health problem associated with high morbidity and mortality. Despite significant research into various pathways involved in the pathophysiology of CKD, the therapeutic options are limited in diabetes and hypertension induced CKD to blood pressure control, hyperglycemia management (in diabetic nephropathy) and reduction of proteinuria, mainly with renin-angiotensin blockade therapy. Recently, renal oxygenation in pathophysiology of CKD progression has received a lot of interest. Several advances have been made in our understanding of the determinants and regulators of renal oxygenation in normal and diseased kidneys. The goal of this review is to discuss the alterations in renal oxygenation (delivery, consumption and tissue oxygen tension) in pre-clinical and clinical studies in diabetic and hypertensive CKD along with the underlying mechanisms and potential therapeutic options.
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Affiliation(s)
- Zhi Zhao Liu
- Division of Nephrology-Hypertension, University of California San Diego School of Medicine, VA San Diego Healthcare SystemSan Diego, CA, United States
| | - Alexander Bullen
- Division of Nephrology-Hypertension, University of California San Diego School of Medicine, VA San Diego Healthcare SystemSan Diego, CA, United States
| | - Ying Li
- Division of Nephrology-Hypertension, University of California San Diego School of Medicine, VA San Diego Healthcare SystemSan Diego, CA, United States
| | - Prabhleen Singh
- Division of Nephrology-Hypertension, University of California San Diego School of Medicine, VA San Diego Healthcare SystemSan Diego, CA, United States
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49
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Williams AN, Conway BN. Effect of high density lipoprotein cholesterol on the relationship of serum iron and hemoglobin with kidney function in diabetes. J Diabetes Complications 2017; 31:958-963. [PMID: 28410926 PMCID: PMC5560583 DOI: 10.1016/j.jdiacomp.2017.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/20/2017] [Accepted: 03/25/2017] [Indexed: 01/09/2023]
Abstract
Findings of increased hemoglobin inside the HDL proteome among persons with diabetes who have haptoglobin 2-2 genotype suggest that iron-induced lipid peroxidation may be involved in diabetic kidney disease. We investigated the relationships of serum hemoglobin and iron with kidney function, and whether this varied by level of HDLc, in 5296 adults with and 49,161 without diabetes. Estimated eGFR was our marker of kidney function. Hemoglobin was positively associated with eGFR among those with diabetes and inversely among those without diabetes (interaction p-value <0.0001). Iron was inversely associated with eGFR regardless of diabetes status. When stratified by median HDLc and median hemoglobin, among persons with diabetes mean eGFR was highest in those with high hemoglobin and low HDLc and lowest in those with both low hemoglobin and low HDLc. This divergent relationship was not observed in the non-diabetic population. In contrast to hemoglobin, high iron and low HDLc were associated with a lower mean eGFR regardless of diabetes status. Our data suggest that among persons with diabetes, both hemoglobin and iron are harmful to kidney function at high levels. Our data also suggest that HDLc may play a role in the relationship of high hemoglobin in kidney function in diabetes.
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Affiliation(s)
- Ashley N Williams
- Department of Epidemiology, West Virginia University, Morgantown, WV
| | - Baqiyyah N Conway
- Department of Epidemiology, West Virginia University, Morgantown, WV.
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50
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Schiffer TA, Friederich-Persson M. Mitochondrial Reactive Oxygen Species and Kidney Hypoxia in the Development of Diabetic Nephropathy. Front Physiol 2017; 8:211. [PMID: 28443030 PMCID: PMC5386984 DOI: 10.3389/fphys.2017.00211] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/23/2017] [Indexed: 12/21/2022] Open
Abstract
The underlying mechanisms in the development of diabetic nephropathy are currently unclear and likely consist of a series of dynamic events from the early to late stages of the disease. Diabetic nephropathy is currently without curative treatments and it is acknowledged that even the earliest clinical manifestation of nephropathy is preceded by an established morphological renal injury that is in turn preceded by functional and metabolic alterations. An early manifestation of the diabetic kidney is the development of kidney hypoxia that has been acknowledged as a common pathway to nephropathy. There have been reports of altered mitochondrial function in the diabetic kidney such as altered mitophagy, mitochondrial dynamics, uncoupling, and cellular signaling through hypoxia inducible factors and AMP-kinase. These factors are also likely to be intertwined in a complex manner. In this review, we discuss how these pathways are connected to mitochondrial production of reactive oxygen species (ROS) and how they may relate to the development of kidney hypoxia in diabetic nephropathy. From available literature, it is evident that early correction and/or prevention of mitochondrial dysfunction may be pivotal in the prevention and treatment of diabetic nephropathy.
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Affiliation(s)
- Tomas A Schiffer
- Department of Medical Cell Biology, Uppsala UniversityUppsala, Sweden.,Department of Medical and Health Sciences, Linköping UniversityLinköping, Sweden
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