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Chen Y, Pei C, Chen Y, Xiao X, Zhang X, Cai K, Deng S, Liang R, Xie Z, Li P, Liao Q. Kidney tea ameliorates hyperuricemia in mice via altering gut microbiota and restoring metabolic profile. Chem Biol Interact 2023; 376:110449. [PMID: 36921834 DOI: 10.1016/j.cbi.2023.110449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 03/02/2023] [Accepted: 03/08/2023] [Indexed: 03/17/2023]
Abstract
Clerodendranthus spicatus (Thunb.) C. Y. Wu, also known as kidney tea (KT), has been widely employed in kidney protection in Chinese Medicine. It has been reported that KT can lower uric acid (UA) and mitigate gout, while the mechanism remains to be elucidated. Given the close relationship between hyperuricemia (HUA), intestinal flora and host metabolism, this study aimed to explore the mechanism by which KT lowers UA from the perspective of the fecal microbiome and metabolome. Initially, mice were intraperitoneally injected with potassium oxonate to induce the HUA model. The results showed that KT markedly reduced the serum level of UA and impaired renal damage in HUA mice. Subsequently, the result of 16S rRNA gene sequencing analysis indicated that KT administration appeared a significant improvement in the structure of the intestinal flora, especially increased the abundances of Roseburia and Enterorhabdus, while decreased the abundances of Ileibacterium and UBA1819. Moreover, the levels of differential metabolites (including twenty-five in feces and eight in serum) identified by untargeted metabolomics returned to normal after KT intervention. Taken together, the mechanism of KT in alleviating HUA is related to the regulation of the intestinal flora and the remodeling of metabolic disorders, which will lay a theoretical foundation for KT as a UA-lowering drug.
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Affiliation(s)
- Ye Chen
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Chaoying Pei
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Ying Chen
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Xiaoyi Xiao
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Xingyuan Zhang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Kaiwei Cai
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Song Deng
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Rongyao Liang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China
| | - Zhiyong Xie
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangming District, Gongchang Road, Shenzhen, Guangdong Province, 518106, China
| | - Pei Li
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China.
| | - Qiongfeng Liao
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Panyu District, No. 232, Waihuan East Road, Guangzhou, Guangdong Province, 510006, China.
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Stasi A, Franzin R, Caggiano G, Losapio R, Fiorentino M, Alfieri C, Gesualdo L, Stallone G, Castellano G. New Frontiers in Sepsis-Induced Acute Kidney Injury and Blood Purification Therapies: The Role of Polymethylmethacrylate Membrane Hemofilter. Blood Purif 2023; 52:1-14. [PMID: 36693337 PMCID: PMC10210082 DOI: 10.1159/000528685] [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: 04/10/2022] [Accepted: 11/17/2022] [Indexed: 01/25/2023]
Abstract
Acute kidney injury (AKI) is a common consequence of sepsis with a mortality rate of up to 40%. The pathogenesis of septic AKI is complex and involves several mechanisms leading to exacerbated inflammatory response associated with renal injury. A large body of evidence suggests that inflammation is tightly linked to AKI through bidirectional interaction between renal and immune cells. Preclinical data from our and other laboratories have identified in complement system activation a crucial mediator of AKI. Partial recovery following AKI could lead to long-term consequences that predispose to chronic dysfunction and may also accelerate the progression of preexisting chronic kidney disease. Recent findings have revealed striking morphological and functional changes in renal parenchymal cells induced by mitochondrial dysfunction, cell cycle arrest via the activation of signaling pathways involved in aging process, microvascular rarefaction, and early fibrosis. Although major advances have been made in our understanding of the pathophysiology of AKI, there are no available preventive and therapeutic strategies in this field. The identification of ideal clinical biomarkers for AKI enables prompt and effective therapeutic strategy that could prevent the progression of renal injury and promote repair process. Therefore, the use of novel biomarkers associated with clinical and functional criteria could provide early interventions and better outcome. Several new drugs for AKI are currently being investigated; however, the complexity of this disease might explain the failure of pharmacological intervention targeting just one of the many systems involved. The hypothesis that blood purification could improve the outcome of septic AKI has attracted much attention. New relevant findings on the role of polymethylmethacrylate-based continuous veno-venous hemofiltration in septic AKI have been reported. Herein, we provide a comprehensive literature review on advances in the pathophysiology of septic AKI and potential therapeutic approaches in this field.
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Affiliation(s)
- Alessandra Stasi
- Renal, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DIMEPRE-J), University of Bari, Bari, Italy
| | - Rossana Franzin
- Renal, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DIMEPRE-J), University of Bari, Bari, Italy
| | - Gianvito Caggiano
- Renal, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DIMEPRE-J), University of Bari, Bari, Italy
| | - Rosa Losapio
- Renal, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DIMEPRE-J), University of Bari, Bari, Italy
| | - Marco Fiorentino
- Renal, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DIMEPRE-J), University of Bari, Bari, Italy
| | - Carlo Alfieri
- Nephrology, Dialysis and Renal Transplant Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Loreto Gesualdo
- Renal, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DIMEPRE-J), University of Bari, Bari, Italy
| | - Giovanni Stallone
- Nephrology Dialysis and Transplantation Unit, Department of Medical and Surgical Sciences, Advanced Research Center on Kidney Aging (A.R.K.A.), University of Foggia, Foggia, Italy
| | - Giuseppe Castellano
- Nephrology, Dialysis and Renal Transplant Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
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McLarnon SR, Wilson K, Patel B, Sun J, Sartain CL, Mejias CD, Musall JB, Sullivan JC, Wei Q, Chen JK, Hyndman KA, Marshall B, Yang H, Fogo AB, O’Connor PM. Lipopolysaccharide Pretreatment Prevents Medullary Vascular Congestion following Renal Ischemia by Limiting Early Reperfusion of the Medullary Circulation. J Am Soc Nephrol 2022; 33:769-785. [PMID: 35115326 PMCID: PMC8970460 DOI: 10.1681/asn.2021081089] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/16/2022] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Vascular congestion of the renal medulla-trapped red blood cells in the medullary microvasculature-is a hallmark finding at autopsy in patients with ischemic acute tubular necrosis. Despite this, the pathogenesis of vascular congestion is not well defined. METHODS In this study, to investigate the pathogenesis of vascular congestion and its role in promoting renal injury, we assessed renal vascular congestion and tubular injury after ischemia reperfusion in rats pretreated with low-dose LPS or saline (control). We used laser Doppler flowmetry to determine whether pretreatment with low-dose LPS prevented vascular congestion by altering renal hemodynamics during reperfusion. RESULTS We found that vascular congestion originated during the ischemic period in the renal venous circulation. In control animals, the return of blood flow was followed by the development of congestion in the capillary plexus of the outer medulla and severe tubular injury early in reperfusion. Laser Doppler flowmetry indicated that blood flow returned rapidly to the medulla, several minutes before recovery of full cortical perfusion. In contrast, LPS pretreatment prevented both the formation of medullary congestion and its associated tubular injury. Laser Doppler flowmetry in LPS-pretreated rats suggested that limiting early reperfusion of the medulla facilitated this protective effect, because it allowed cortical perfusion to recover and clear congestion from the large cortical veins, which also drain the medulla. CONCLUSIONS Blockage of the renal venous vessels and a mismatch in the timing of cortical and medullary reperfusion results in congestion of the outer medulla's capillary plexus and promotes early tubular injury after renal ischemia. These findings indicate that hemodynamics during reperfusion contribute to the renal medulla's susceptibility to ischemic injury.
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Affiliation(s)
- Sarah R. McLarnon
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Katie Wilson
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Bansari Patel
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Jingping Sun
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Christina L. Sartain
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Christopher D. Mejias
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Jacqueline B. Musall
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Jennifer C. Sullivan
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Qingqing Wei
- Department of Cell Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Jian-Kang Chen
- Department of Cell Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Kelly A. Hyndman
- Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Brendan Marshall
- Department of Cell Biology and Anatomy, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Haichun Yang
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Agnes B. Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Paul M. O’Connor
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, Georgia
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Abstract
Sepsis is a major cause of acute kidney injury (AKI) among patients in the intensive care unit. However, the numbers of basic science papers for septic AKI account for only 1% of all publications on AKI. This may be partially attributable to the specific pathophysiology of septic AKI as compared to that of the other types of AKI because it shows only modest histological changes despite functional decline and often requires real-time functional analysis. To increase the scope of research in this field, this article reviews the basic research information that has been reported thus far on the subject of septic AKI, mainly from the viewpoint of functional dysregulation, including some knowledge acquired with multiphoton intravital imaging. Moreover, the efficacy and limitation of the potential novel therapies are discussed. Finally, the author proposes several points that should be considered when designing the study, such as monitoring the long-term effects of the intervention and reflecting the clinical settings for identifying the molecular mechanisms and for challenging the intervention effects.
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Affiliation(s)
- Daisuke Nakano
- Department of Pharmacology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa, 761-0793, Japan.
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Del Vecchio L, Locatelli F. Hypoxia response and acute lung and kidney injury: possible implications for therapy of COVID-19. Clin Kidney J 2020; 13:494-499. [PMID: 32905208 PMCID: PMC7467604 DOI: 10.1093/ckj/sfaa149] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 10/09/2020] [Indexed: 12/11/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) is a pandemic of unprecedented severity affecting millions of people around the world and causing several hundred thousands of deaths. The presentation of the disease ranges from asymptomatic manifestations through to acute respiratory distress syndrome with the necessity of mechanical ventilation. Cytokine storm and maladaptive responses to the viral spread in the body could be responsible for the severity of disease. Many patients develop acute kidney injury (AKI) during the course of their disease, especially in more severe cases. Many factors could cause kidney damage during infection from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. It is still unclear whether direct viral damage or the overexpression of cytokines and inflammatory factors are preeminent. According to autoptic studies, in most of the cases, AKI is due proximal tubular damage. However, cases of collapsing focal segmental glomerulosclerosis were reported as well in the absence of signs of direct viral infection of the kidney. Considering that severe hypoxia is a hallmark of severe SARS-CoV-2 infection, the involvement of the hypoxia-inducible factor (HIF) system is very likely, possibly influencing the inflammatory response and outcome in both the lungs and kidneys. Several bodies of evidence have shown a possible role of the HIF pathway during AKI in various kidney disease models. Similar observations were made in the setting of acute lung injury. In both organs, HIF activation by means of inhibition of the prolyl-hydroxylases domain (PHD) could be protective. Considering these promising experimental data, we hypothesize that PHD inhibitors could be considered as a possible new therapy against severe SARS-CoV-2 infection.
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Affiliation(s)
| | - Francesco Locatelli
- Past Director, Department of Nephrology and Dialysis, Alessandro Manzoni Hospital, ASST Lecco, Lecco, Italy
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Negre-Salvayre A, Guerby P, Gayral S, Laffargue M, Salvayre R. Role of reactive oxygen species in atherosclerosis: Lessons from murine genetic models. Free Radic Biol Med 2020; 149:8-22. [PMID: 31669759 DOI: 10.1016/j.freeradbiomed.2019.10.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 12/19/2022]
Abstract
Atherosclerosis is a multifactorial chronic and inflammatory disease of medium and large arteries, and the major cause of cardiovascular morbidity and mortality worldwide. The pathogenesis of atherosclerosis involves a number of risk factors and complex events including hypercholesterolemia, endothelial dysfunction, increased permeability to low density lipoproteins (LDL) and their sequestration on extracellular matrix in the intima of lesion-prone areas. These events promote LDL modifications, particularly by oxidation, which generates acute and chronic inflammatory responses implicated in atherogenesis and lesion progression. Reactive oxygen species (ROS) (which include both free radical and non-free radical oxygen intermediates), play a key-role at each step of atherogenesis, in endothelial dysfunction, LDL oxidation, and inflammatory events involved in the initiation and development of atherosclerosis lesions. Most advanced knowledge supporting the "oxidative theory of atherosclerosis" i.e. the nature and the cellular sources of ROS and antioxidant defences, as well as the mechanisms involved in the redox balance, is based on the use of genetically engineered animals, i.e. transgenic, genetically modified, or altered for systems producing or neutralizing ROS in the vessels. This review summarizes the results obtained from animals genetically manipulated for various sources of ROS or antioxidant defences in the vascular wall, and their relevance (advance or limitation), for understanding the place and role of ROS in atherosclerosis.
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Affiliation(s)
| | - Paul Guerby
- Inserm U-1048, Université de Toulouse, France; Pôle de gynécologie obstétrique, Hôpital Paule-de-Viguier, CHU de Toulouse, France
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7
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Xanthine Oxidase Inhibitor Febuxostat Exerts an Anti-Inflammatory Action and Protects against Diabetic Nephropathy Development in KK-Ay Obese Diabetic Mice. Int J Mol Sci 2019; 20:ijms20194680. [PMID: 31546603 PMCID: PMC6801943 DOI: 10.3390/ijms20194680] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/14/2019] [Accepted: 09/17/2019] [Indexed: 12/13/2022] Open
Abstract
Hyperuricemia has been recognized as a risk factor for insulin resistance as well as one of the factors leading to diabetic kidney disease (DKD). Since DKD is the most common cause of end-stage renal disease, we investigated whether febuxostat, a xanthine oxidase (XO) inhibitor, exerts a protective effect against the development of DKD. We used KK-Ay mice, an established obese diabetic rodent model. Eight-week-old KK-Ay mice were provided drinking water with or without febuxostat (15 μg/mL) for 12 weeks and then subjected to experimentation. Urine albumin secretion and degrees of glomerular injury judged by microscopic observations were markedly higher in KK-Ay than in control lean mice. These elevations were significantly normalized by febuxostat treatment. On the other hand, body weights and high serum glucose concentrations and glycated albumin levels of KK-Ay mice were not affected by febuxostat treatment, despite glucose tolerance and insulin tolerance tests having revealed febuxostat significantly improved insulin sensitivity and glucose tolerance. Interestingly, the IL-1β, IL-6, MCP-1, and ICAM-1 mRNA levels, which were increased in KK-Ay mouse kidneys as compared with normal controls, were suppressed by febuxostat administration. These data indicate a protective effect of XO inhibitors against the development of DKD, and the underlying mechanism likely involves inflammation suppression which is independent of hyperglycemia amelioration.
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Rempel LCT, Faustino VD, Foresto-Neto O, Fanelli C, Arias SCA, Moreira GCDS, Nascimento TF, Ávila VF, Malheiros DMAC, Câmara NOS, Fujihara CK, Zatz R. Chronic exposure to hypoxia attenuates renal injury and innate immunity activation in the remnant kidney model. Am J Physiol Renal Physiol 2019; 317:F1285-F1292. [PMID: 31461352 DOI: 10.1152/ajprenal.00367.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Hypoxia is thought to influence the pathogenesis of chronic kidney disease, but direct evidence that prolonged exposure to tissue hypoxia initiates or aggravates chronic kidney disease is lacking. We tested this hypothesis by chronically exposing normal rats and rats with 5/6 nephrectomy (Nx) to hypoxia. In addition, we investigated whether such effect of hypoxia would involve activation of innate immunity. Adult male Munich-Wistar rats underwent Nx (n = 54) or sham surgery (sham; n = 52). Twenty-six sham rats and 26 Nx rats remained in normoxia, whereas 26 sham rats and 28 Nx rats were kept in a normobaric hypoxia chamber (12% O2) for 8 wk. Hypoxia was confirmed by immunohistochemistry for pimonidazole. Hypoxia was confined to the medullary area in sham + normoxia rats and spread to the cortical area in sham + hypoxia rats, without changing the peritubular capillary density. Exposure to hypoxia promoted no renal injury or elevation of the content of IL-1β or Toll-like receptor 4 in sham rats. In Nx, hypoxia also extended to the cortical area without ameliorating the peritubular capillary rarefaction but, unexpectedly, attenuated hypertension, inflammation, innate immunity activation, renal injury, and oxidative stress. The present study, in disagreement with current concepts, shows evidence that hypoxia exerts a renoprotective effect in the Nx model instead of acting as a factor of renal injury. The mechanisms for this unexpected beneficial effect are unclear and may involve NF-κB inhibition, amelioration of oxidative stress, and limitation of angiotensin II production by the renal tissue.
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Affiliation(s)
- Lisienny Campoli Tono Rempel
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Viviane Dias Faustino
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Orestes Foresto-Neto
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Camilla Fanelli
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Simone Costa Alarcon Arias
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | | | - Thalita Fabiana Nascimento
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Victor Ferreira Ávila
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | | | - Niels Olsen Saraiva Câmara
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil.,Laboratory of Transplantation Immunobiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Clarice Kazue Fujihara
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Roberto Zatz
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
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9
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Hypoxia and Hypoxia-Inducible Factors in Kidney Injury and Repair. Cells 2019; 8:cells8030207. [PMID: 30823476 PMCID: PMC6468851 DOI: 10.3390/cells8030207] [Citation(s) in RCA: 155] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 02/21/2019] [Accepted: 02/25/2019] [Indexed: 02/07/2023] Open
Abstract
Acute kidney injury (AKI) is a major kidney disease characterized by an abrupt loss of renal function. Accumulating evidence indicates that incomplete or maladaptive repair after AKI can result in kidney fibrosis and the development and progression of chronic kidney disease (CKD). Hypoxia, a condition of insufficient supply of oxygen to cells and tissues, occurs in both acute and chronic kidney diseases under a variety of clinical and experimental conditions. Hypoxia-inducible factors (HIFs) are the "master" transcription factors responsible for gene expression in hypoxia. Recent researches demonstrate that HIFs play an important role in kidney injury and repair by regulating HIF target genes, including microRNAs. However, there are controversies regarding the pathological roles of HIFs in kidney injury and repair. In this review, we describe the regulation, expression, and functions of HIFs, and their target genes and related functions. We also discuss the involvement of HIFs in AKI and kidney repair, presenting HIFs as effective therapeutic targets.
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10
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Inoue MK, Yamamotoya T, Nakatsu Y, Ueda K, Inoue Y, Matsunaga Y, Sakoda H, Fujishiro M, Ono H, Morii K, Sasaki K, Masaki T, Suzuki Y, Asano T, Kushiyama A. The Xanthine Oxidase Inhibitor Febuxostat Suppresses the Progression of IgA Nephropathy, Possibly via Its Anti-Inflammatory and Anti-Fibrotic Effects in the gddY Mouse Model. Int J Mol Sci 2018; 19:E3967. [PMID: 30544662 PMCID: PMC6320819 DOI: 10.3390/ijms19123967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 11/28/2018] [Accepted: 12/05/2018] [Indexed: 12/29/2022] Open
Abstract
Recent clinical studies have demonstrated the protective effect of xanthine oxidase (XO) inhibitors against chronic kidney diseases, although the underlying molecular mechanisms remain unclear. However, to date, neither clinical nor basic research has been carried out to elucidate the efficacy of XO inhibitor administration for IgA nephropathy. We thus investigated whether febuxostat, an XO inhibitor, exerts a protective effect against the development of IgA nephropathy, using gddY mice as an IgA nephropathy rodent model. Eight-week-old gddY mice were provided drinking water with (15 μg/mL) or without febuxostat for nine weeks and then subjected to experimentation. Elevated serum creatinine and degrees of glomerular sclerosis and fibrosis, judged by microscopic observations, were significantly milder in the febuxostat-treated than in the untreated gddY mice, while body weights and serum IgA concentrations did not differ between the two groups. In addition, elevated mRNA levels of inflammatory cytokines such as TNFα, MCP-1, IL-1β, and IL-6, collagen isoforms and chemokines in the gddY mouse kidneys were clearly normalized by the administration of febuxostat. These data suggest a protective effect of XO inhibitors against the development of IgA nephropathy, possibly via suppression of inflammation and its resultant fibrotic changes, without affecting the serum IgA concentration.
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Affiliation(s)
- Masa-Ki Inoue
- Department of Medical Science, Graduate School of Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Takeshi Yamamotoya
- Department of Medical Science, Graduate School of Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Yusuke Nakatsu
- Department of Medical Science, Graduate School of Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Koji Ueda
- Department of Medical Science, Graduate School of Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Yuki Inoue
- Department of Medical Science, Graduate School of Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Yasuka Matsunaga
- Center for Translational Research in Infection & Inflammation, School of Medicine, Tulane University, 6823 St. Charles Avenue, New Orleans, LA 70118, USA.
| | - Hideyuki Sakoda
- Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
| | - Midori Fujishiro
- Division of Diabetes and Metabolic Diseases, Nihon University School of Medicine, Itabashi, Tokyo 173-8610, Japan.
| | - Hiraku Ono
- Department of Clinical Cell Biology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba 260-8670, Japan.
| | - Kenichi Morii
- Department of Nephrology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Kensuke Sasaki
- Department of Nephrology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Takao Masaki
- Department of Nephrology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Yusuke Suzuki
- Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Tomoichiro Asano
- Department of Medical Science, Graduate School of Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8551, Japan.
| | - Akifumi Kushiyama
- Division of Diabetes and Metabolism, The Institute for Adult Diseases, Asahi Life Foundation, Chuo-ku, Tokyo 103-0002, Japan.
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11
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Plotnikov EY, Pavlenko TA, Pevzner IB, Zorova LD, Manskikh VN, Silachev DN, Sukhikh GT, Zorov DB. The role of oxidative stress in acute renal injury of newborn rats exposed to hypoxia and endotoxin. FEBS J 2017; 284:3069-3078. [DOI: 10.1111/febs.14177] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/05/2017] [Accepted: 07/13/2017] [Indexed: 01/24/2023]
Affiliation(s)
- Egor Y. Plotnikov
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
- V. I. Kulakov Research Center of Obstetrics, Gynecology and Perinatology; Ministry of Health of the Russian Federation; Moscow Russia
| | - Tatiana A. Pavlenko
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
- Russian Cardiology Research and Production Center; Moscow Russia
| | - Irina B. Pevzner
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
- V. I. Kulakov Research Center of Obstetrics, Gynecology and Perinatology; Ministry of Health of the Russian Federation; Moscow Russia
| | - Ljubava D. Zorova
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
- V. I. Kulakov Research Center of Obstetrics, Gynecology and Perinatology; Ministry of Health of the Russian Federation; Moscow Russia
- International Laser Center; M.V. Lomonosov Moscow State University; Russia
| | - Vasily N. Manskikh
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
| | - Denis N. Silachev
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
- V. I. Kulakov Research Center of Obstetrics, Gynecology and Perinatology; Ministry of Health of the Russian Federation; Moscow Russia
| | - Gennady T. Sukhikh
- V. I. Kulakov Research Center of Obstetrics, Gynecology and Perinatology; Ministry of Health of the Russian Federation; Moscow Russia
| | - Dmitry B. Zorov
- A.N. Belozersky Institute of Physico-Chemical Biology; M.V. Lomonosov Moscow State University; Russia
- V. I. Kulakov Research Center of Obstetrics, Gynecology and Perinatology; Ministry of Health of the Russian Federation; Moscow Russia
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Role of Uric Acid Metabolism-Related Inflammation in the Pathogenesis of Metabolic Syndrome Components Such as Atherosclerosis and Nonalcoholic Steatohepatitis. Mediators Inflamm 2016; 2016:8603164. [PMID: 28070145 PMCID: PMC5192336 DOI: 10.1155/2016/8603164] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 11/03/2016] [Accepted: 11/15/2016] [Indexed: 02/07/2023] Open
Abstract
Uric acid (UA) is the end product of purine metabolism and can reportedly act as an antioxidant. However, recently, numerous clinical and basic research approaches have revealed close associations of hyperuricemia with several disorders, particularly those comprising the metabolic syndrome. In this review, we first outline the two molecular mechanisms underlying inflammation occurrence in relation to UA metabolism; one is inflammasome activation by UA crystallization and the other involves superoxide free radicals generated by xanthine oxidase (XO). Importantly, recent studies have demonstrated the therapeutic or preventive effects of XO inhibitors against atherosclerosis and nonalcoholic steatohepatitis, which were not previously considered to be related, at least not directly, to hyperuricemia. Such beneficial effects of XO inhibitors have been reported for other organs including the kidneys and the heart. Thus, a major portion of this review focuses on the relationships between UA metabolism and the development of atherosclerosis, nonalcoholic steatohepatitis, and related disorders. Although further studies are necessary, XO inhibitors are a potentially novel strategy for reducing the risk of many forms of organ failure characteristic of the metabolic syndrome.
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BQ123 Stimulates Skeletal Muscle Antioxidant Defense via Nrf2 Activation in LPS-Treated Rats. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2016:2356853. [PMID: 26823945 PMCID: PMC4707360 DOI: 10.1155/2016/2356853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/24/2015] [Accepted: 10/11/2015] [Indexed: 01/02/2023]
Abstract
Little is understood of skeletal muscle tissue in terms of oxidative stress and inflammation. Endothelin-1 is an endogenous, vasoconstrictive peptide which can induce overproduction of reactive oxygen species and proinflammatory cytokines. The aim of this study was to evaluate whether BQ123, an endothelin-A receptor antagonist, influences the level of TNF-α, IL-6, SOD-1, HO-1, Nrf2 mRNA, and NF-κB subunit RelA/p65 mRNA in the femoral muscle obtained from endotoxemic rats. Male Wistar rats were divided into 4 groups (n = 6) and received iv (1) saline (control), (2) LPS (15 mg/kg), (3) BQ123 (1 mg/kg), (4) BQ123 (1 mg/kg), and LPS (15 mg/kg, resp.) 30 min later. Injection of LPS led to significant increase in levels of RelA/p65 mRNA, TNF-α, and IL-6, while content of SOD-1, HO-1, and Nrf2 mRNA was unchanged. Administration of BQ123 prior to LPS challenge resulted in a significant reduction in RelA/p65 mRNA, TNF-α, and IL-6 levels, as well as markedly elevated concentrations of SOD-1, HO-1, and Nrf2 mRNA. BQ123 appears to enhance antioxidant defense and prevent production of TNF-α and IL-6 in skeletal muscle of LPS-treated rat. In conclusion, endothelin-A receptor antagonism exerts significant impact on the skeletal muscle favouring anti-inflammatory effects and protection against oxidative stress.
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Cimolai MC, Vanasco V, Marchini T, Magnani ND, Evelson P, Alvarez S. α-Lipoic acid protects kidney from oxidative stress and mitochondrial dysfunction associated to inflammatory conditions. Food Funct 2015; 5:3143-50. [PMID: 25272049 DOI: 10.1039/c4fo00489b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An adequate redox status is important for maintaining mitochondrial function in inflammatory conditions. The aim of this work was to evaluate the effects of α-lipoic acid (LA) in kidney oxidative metabolism and mitochondrial function in lipopolysaccharide (LPS) treated rats. Sprague-Dawley rats (female, 45 ± 5 days old) were treated with LPS (10 mg kg(-1)) and/or LA (100 mg kg(-1)). It was observed in LPS-treated animals that the LA prevented the increase in 1.2 fold of NO production, decreased (30-40%) mitochondrial complex I-III and IV activities, and decreased (26%) membrane potential and cardiolipin oxidation (76%). No differences were observed in mitochondrial O2 consumption, mitochondrial complex II-III activity, and ATP production when LPS group was compared to LA + LPS group. Based on the improvement of mitochondrial function, the decreased production of mitochondrial NO and restoration of cardiolipin levels, this work provides a new evidence that α-lipoic acid protects kidney from oxidative stress and mitochondrial dysfunction.
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Affiliation(s)
- Maria Cecilia Cimolai
- Institute of Biochemistry and Molecular Medicine, School of Pharmacy and Biochemistry, University of Buenos Aires-CONICET, Junín 956, C1113AAD Buenos Aires, Argentina.
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15
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Blockade of the N-Methyl-D-Aspartate Glutamate Receptor Ameliorates Lipopolysaccharide-Induced Renal Insufficiency. PLoS One 2015; 10:e0132204. [PMID: 26133372 PMCID: PMC4489897 DOI: 10.1371/journal.pone.0132204] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 06/12/2015] [Indexed: 11/28/2022] Open
Abstract
N-methyl-D-aspartate (NMDA) receptor activation in rat kidney reduces renal perfusion and ultrafiltration. Hypoperfusion-induced ischemia is the most frequent cause of functional insufficiency in the endotoxemic kidney. Here, we used non-hypotensive rat model of lipopolysaccharide-induced endotoxemia to examine whether NMDA receptor hyperfunction contributes to acute kidney injury. Lipopolysaccharide-induced renal damage via increased enzymuria and hemodynamic impairments were ameliorated by co-treatment with the NMDA receptor blocker, MK-801. The NMDA receptor NR1 subunit in the rat kidney mainly co-localized with serine racemase, an enzyme responsible for synthesizing the NMDA receptor co-agonist, D-serine. The NMDA receptor hyperfunction in lipopolysaccharide-treated kidneys was demonstrated by NR1 and serine racemase upregulation, particularly in renal tubules, and by increased D-serine levels. Lipopolysaccharide also induced cell damage in cultured tubular cell lines and primary rat proximal tubular cells. This damage was mitigated by MK-801 and by small interfering RNA targeting NR1. Lipopolysaccharide increased cytokine release in tubular cell lines via toll-like receptor 4. The release of interleukin-1β from these cells are the most abundant. An interleukin-1 receptor antagonist not only attenuated cell death but also abolished lipopolysaccharide-induced NR1 and serine racemase upregulation and increases in D-serine secretion, suggesting that interleukin-1β-mediated NMDA receptor hyperfunction participates in lipopolysaccharide-induced tubular damage. The results of this study indicate NMDA receptor hyperfunction via cytokine effect participates in lipopolysaccharide-induced renal insufficiency. Blockade of NMDA receptors may represent a promising therapeutic strategy for the treatment of sepsis-associated renal failure.
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Yang CC, Yao CA, Yang JC, Chien CT. Sialic acid rescues repurified lipopolysaccharide-induced acute renal failure via inhibiting TLR4/PKC/gp91-mediated endoplasmic reticulum stress, apoptosis, autophagy, and pyroptosis signaling. Toxicol Sci 2014; 141:155-65. [PMID: 24973090 DOI: 10.1093/toxsci/kfu121] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Lipopolysaccharides (LPS) through Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) activation induce systemic inflammation where oxidative damage plays a key role in multiple organ failure. Because of the neutralization of LPS toxicity by sialic acid (SA), we determined its effect and mechanisms on repurified LPS (rLPS)-evoked acute renal failure. We assessed the effect of intravenous SA (10 mg/kg body weight) on rLPS-induced renal injury in female Wistar rats by evaluating blood and kidney reactive oxygen species (ROS) responses, renal and systemic hemodynamics, renal function, histopathology, and molecular mechanisms. SA can interact with rLPS through a high binding affinity. rLPS dose- and time-dependently reduced arterial blood pressure, renal microcirculation and blood flow, and increased vascular resistance in the rats. rLPS enhanced monocyte/macrophage (ED-1) infiltration and ROS production and impaired kidneys by triggering p-IRE1α/p-JNK/CHOP/GRP78/ATF4-mediated endoplasmic reticulum (ER) stress, Bax/PARP-mediated apoptosis, Beclin-1/Atg5-Atg12/LC3-II-mediated autophagy, and caspase 1/IL-1β-mediated pyroptosis in the kidneys. SA treatment at 30 min, but not 60 min after rLPS stimulation, gp91 siRNA and protein kinase C-α (PKC) inhibitor efficiently rescued rLPS-induced acute renal failure via inhibition of TLR4/PKC/NADPH oxidase gp91-mediated ER stress, apoptosis, autophagy and pyroptosis in renal proximal tubular cells, and rat kidneys. In response to rLPS or IFNγ, the enhanced Atg5, FADD, LC3-II, and PARP expression can be inhibited by Atg5 siRNA. Albumin (10 mg/kg body weight) did not rescue rLPS-induced injury. In conclusion, early treatment (within 30 min) of SA attenuates rLPS-induced renal failure via the reduction in LPS toxicity and subsequently inhibiting rLPS-activated TLR4/PKC/gp91/ER stress/apoptosis/autophagy/pyroptosis signaling.
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Affiliation(s)
- Chih-Ching Yang
- Department of Internal Medicine, National Yang-Ming University, Taipei 11221, Taiwan Department of Family Medicine, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Chien-An Yao
- National Taiwan University Hospital and College of Medicine, Taipei 10016, Taiwan
| | - Jyh-Chin Yang
- Department of Life Science, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Chiang-Ting Chien
- Department of Planning, Ministry of Health and Welfare, Executive Yuan, Taipei 11558, Taiwan
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Augmented renal prostacyclin by intrarenal bicistronic cyclo-oxygenase-1/prostacyclin synthase gene transfer attenuates renal ischemia-reperfusion injury. Transplantation 2014; 96:1043-51. [PMID: 24092384 DOI: 10.1097/tp.0b013e3182a77e52] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND We elucidated the protective mechanism of increased prostacyclin (PGI2) derived from adenoviral cyclo-oxygenase (COX)-1/prostacyclin synthase (PGIS) (Adv-COPI) gene transfer in rat kidneys with ischemia-reperfusion (I/R) injury. METHODS We tended to augment PGI2 production by intrarenal arterial Adv-COPI administration with renal venous clamping in female Wistar rats. After Adv-COPI transfection, we evaluated the renal COX-1 and PGIS protein expression and PGI2 and prostaglandin E2 (PGE2) levels in the kidney and renal venous plasma. We evaluated the protective effect of PGI2 on hypoxia/reoxygenation-induced tubular cells injury or I/R kidneys by measuring oxidative stress, necrosis, apoptosis, and autophagy in tubules and kidneys and determining renal function, microcirculation, and accumulation of tubular 4-hydroxynonenal in the kidney in vivo. RESULTS Adv-COPI treatment selectively augmented COX-1 and PGIS protein expression in the renal proximal and distal tubules and significantly increased PGI2, not PGE2, production in the renal venous plasma and kidney at the baseline level. I/R markedly depressed renal blood flow and increased the production in O2, PGE2, the expression in P47 and Rac-1 expression of two nicotinamide adenine dinucleotide phosphate oxidase subunits, cytosolic cytochrome C release, proapoptotic marker lamin expression, the pathologic appearance of necrosis, apoptosis, and autophagy, and blood urea nitrogen and creatinine levels in the damaged kidneys. Adv-COPI protected distal and proximal tubules against hypoxia/reoxygenation-enhanced oxidative stress and autophagic, apoptotic, and necrotic cell death. Adv-COPI significantly improved renal function by restoring renal blood flow, reducing nicotinamide adenine dinucleotide phosphate oxidase-derived and mitochondria-derived oxidative stress, and necrosis, apoptosis, and autophagy. CONCLUSIONS Increased PGI2 by Adv-COPI protects the kidney against I/R-induced oxidative stress, necrosis, apoptosis and autophagy.
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18
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Patil NK, Parajuli N, MacMillan-Crow LA, Mayeux PR. Inactivation of renal mitochondrial respiratory complexes and manganese superoxide dismutase during sepsis: mitochondria-targeted antioxidant mitigates injury. Am J Physiol Renal Physiol 2014; 306:F734-43. [PMID: 24500690 DOI: 10.1152/ajprenal.00643.2013] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Acute kidney injury (AKI) is a complication of sepsis and leads to a high mortality rate. Human and animal studies suggest that mitochondrial dysfunction plays an important role in sepsis-induced multi-organ failure; however, the specific mitochondrial targets damaged during sepsis remain elusive. We used a clinically relevant cecal ligation and puncture (CLP) murine model of sepsis and assessed renal mitochondrial function using high-resolution respirometry, renal microcirculation using intravital microscopy, and renal function. CLP caused a time-dependent decrease in mitochondrial complex I and II/III respiration and reduced ATP. By 4 h after CLP, activity of manganese superoxide dismutase (MnSOD) was decreased by 50% and inhibition was sustained through 36 h. These events were associated with increased mitochondrial superoxide generation. We then evaluated whether the mitochondria-targeted antioxidant Mito-TEMPO could reverse renal mitochondrial dysfunction and attenuate sepsis-induced AKI. Mito-TEMPO (10 mg/kg) given at 6 h post-CLP decreased mitochondrial superoxide levels, protected complex I and II/III respiration, and restored MnSOD activity by 18 h. Mito-TEMPO also improved renal microcirculation and glomerular filtration rate. Importantly, even delayed therapy with a single dose of Mito-TEMPO significantly increased 96-h survival rate from 40% in untreated septic mice to 80%. Thus, sepsis causes sustained inactivation of three mitochondrial targets that can lead to increased mitochondrial superoxide. Importantly, even delayed therapy with Mito-TEMPO alleviated kidney injury, suggesting that it may be a promising approach to treat septic AKI.
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Affiliation(s)
- Naeem K Patil
- Dept. of Pharmacology and Toxicology, Univ. of Arkansas for Medical Sciences, 325 Jack Stephens Dr., Biomedical Bldg. I, 323D, Little Rock, AR 72205.
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Boesen EI. Chronic elevation of IL-1β induces diuresis via a cyclooxygenase 2-mediated mechanism. Am J Physiol Renal Physiol 2013; 305:F189-98. [PMID: 23657858 DOI: 10.1152/ajprenal.00075.2013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Chronic renal inflammation is an increasingly recognized phenomenon in multiple disease states, but the impact of specific cytokines on renal function is unclear. Previously, we found that 14-day interleukin-1β (IL-1β) infusion increased urine flow in mice. To determine the mechanism by which this occurs, the current study tested the possible involvement of three classical prodiuretic pathways. Chronic IL-1β infusion significantly increased urine flow (6.5 ± 1 ml/day at day 14 vs. 2.3 ± 0.3 ml/day in vehicle group; P < 0.05) and expression of cyclooxygenase (COX)-2, all three nitric oxide synthase (NOS) isoforms, and endothelin (ET)-1 in the kidney (P < 0.05 in all cases). Urinary prostaglandin E metabolite (PGEM) excretion was also significantly increased at day 14 of IL-1β infusion (1.21 ± 0.26 vs. 0.29 ± 0.06 ng/day in vehicle-infused mice; P = 0.001). The selective COX-2 inhibitor celecoxib markedly attenuated urinary PGEM excretion and abolished the diuretic response to chronic IL-1β infusion. In contrast, deletion of NOS3, or inhibition of NOS1 with L-VNIO, did not blunt the diuretic effect of IL-1β, nor did pharmacological blockade of endothelin ETA and ETB receptors with A-182086. Consistent with a primary effect on water transport, IL-1β infusion markedly reduced inner medullary aquaporin-2 expression (P < 0.05) and did not alter urinary Na⁺ or K⁺ excretion. These data indicate a critical role for COX-2 in mediating the effects of chronic IL-1β elevation on the kidney.
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Affiliation(s)
- E I Boesen
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA.
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20
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Nicaragua revisited: evidence of lower prevalence of chronic kidney disease in a high-altitude, coffee-growing village. J Nephrol 2012; 25:533-40. [PMID: 21956767 DOI: 10.5301/jn.5000028] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2011] [Indexed: 12/19/2022]
Abstract
BACKGROUND Chronic kidney disease (CKD) is found at epidemic levels in certain populations of the Pacific Coast in northwestern Nicaragua especially in younger men. There are knowledge gaps concerning CKD's prevalence in regions at higher altitudes. METHODS A cross-sectional study of adults between the ages of 20 and 60 years in 1 coffee-growing village in Nicaragua located at 1,000 m above sea level (MASL) altitude was performed. Predictors included participant sex, age, occupation, conventional CKD risk factors and other factors associated with CKD suggested by previous surveys in Central America. Outcomes included serum creatinine (SCr) values >1.2 mg/dL for men and >0.9 mg/dL for women, estimated glomerular filtration rate (GFR) <60 ml/min per 1.73 m2, dipstick proteinuria stratified as microalbuminuria (30-300 mg/dL) and macroalbuminuria (>300 mg/dL), hypertension and body mass index. RESULTS Of 324 eligible participants, 293 were interviewed (90.4%), and 267 of those received the physical exam (82.4% overall). Of the sample, 45% were men. Prevalence rate of estimated GFR <60 ml/min per 1.73 m2 was 0 for men (0%) and 2 for women (1.4%). The prevalence of at least microalbuminuria was significantly higher among men compared with women (27.5% vs. 21.4%, respectively; p=0.02). CONCLUSIONS The CKD prevalence in this village is comparable to a previously studied Nicaraguan coffee-farming region and much lower than previously screened portions of northwestern Nicaragua. There is heterogeneity in CKD prevalence across Nicaragua. At this time, screenings should target individuals living in previously identified, higher risk regions. More work is needed to understand determinants of CKD in this resource-poor nation.
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Neutrophil priming by hypoxic preconditioning protects against epithelial barrier damage and enteric bacterial translocation in intestinal ischemia/reperfusion. J Transl Med 2012; 92:783-96. [PMID: 22370946 DOI: 10.1038/labinvest.2012.11] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intestinal ischemia/reperfusion (I/R) induces mucosal barrier dysfunction and bacterial translocation (BT). Neutrophil-derived oxidative free radicals have been incriminated in the pathogenesis of ischemic injury in various organs, but their role in the bacteria-containing intestinal tract is debatable. Primed neutrophils are characterized by a faster and higher respiratory burst activity associated with more robust bactericidal effects on exposure to a second stimulus. Hypoxic preconditioning (HPC) attenuates ischemic injury in brain, heart, lung and kidney; no reports were found in the gut. Our aim is to investigate whether neutrophil priming by HPC protects against intestinal I/R-induced barrier damage and bacterial influx. Rats were raised in normoxia (NM) or kept in a hypobaric hypoxic chamber (380 Torr) 17 h/day for 3 weeks for HPC, followed by sham operation or intestinal I/R. Gut permeability was determined by using an ex vivo macromolecular flux assay and an in vivo magnetic resonance imaging-based method. Liver and spleen homogenates were plated for bacterial culturing. Rats raised in HPC showed diminished levels of BT, and partially improved mucosal histopathology and epithelial barrier function compared with the NM groups after intestinal I/R. Augmented cytokine-induced neutrophil chemoattractant (CINC)-1 and -3 levels and myeloperoxidase activity correlated with enhanced infiltration of neutrophils in intestines of HPC-I/R compared with NM-I/R rats. HPC alone caused blood neutrophil priming, as shown by elevated production of superoxide and hydrogen peroxide on stimulation, increased membrane translocation of cytosolic p47(phox) and p67(phox), as well as augmented bacterial-killing and phagocytotic activities. Neutrophil depletion reversed the mucosal protection by HPC, and aggravated intestinal leakiness and BT following I/R. In conclusion, neutrophil priming by HPC protects against I/R-induced BT via direct antimicrobial activity by oxidative respiratory bursts and through promotion of epithelial barrier integrity for luminal confinement of enteric bacteria.
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Efrati S, Berman S, Hamad RA, Siman-Tov Y, Ilgiyaev E, Maslyakov I, Weissgarten J. Effect of captopril treatment on recuperation from ischemia/reperfusion-induced acute renal injury. Nephrol Dial Transplant 2011; 27:136-45. [PMID: 21680852 DOI: 10.1093/ndt/gfr256] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Ischemia/reperfusion triggers acute kidney injury (AKI), mainly via aggravating hypoxia, oxidative stress, inflammation and renin-angiotensin system (RAS) activation. We investigated the role of angiotensin-converting enzyme (ACE) inhibition on the progression of AKI in a rat model of ischemia/reperfusion. METHODS Ninety-nine Sprague-Dawley rats were subjected to 1 h ischemia/reperfusion and/or left unilateral nephrectomy, with concurrent intraperitoneal implantation of Alzet pump. Via this pump, they were continuously infused with captopril 0.5 mg/kg/day, captopril 2 mg/kg/day or saline. The rats were sacrificed following 24, 48 or 168 h. Blood samples, 24-h urine collections and kidneys were allocated, to evaluate renal function, angiotensin-II, nitric oxide (NO), apoptosis, hypoxia, oxidative stress and inflammation. RESULTS Serum creatinine and cystatin-C significantly increased in ischemic rats, coinciding with histopathologic intrarenal damage, decreased NO, augmented angiotensin-II, interleukin (IL)-6, IL-10, transforming growth factor-beta. At the acute reperfusion stage, captopril prevented excessive angiotensin-II synthesis, ameliorated renal dysfunction, inhibited intrarenal inflammation and improved histopathologic findings. Most of the renoprotective effects of captopril were limited predominantly to acute reperfusion stage. Concurrently, captopril significantly decreased NO availability, exacerbated intrarenal hypoxia and augmented oxidative stress. CONCLUSIONS At the acute stage of renal ischemia/reperfusion-induced AKI, ACE inhibition substantially contributed to the amelioration of acute injury by improving renal function, inhibiting systemic and intrarenal angiotensin-II, attenuating intrarenal inflammation and preserving renal tissue structure. Later on, at the post-reperfusion stage, most of the beneficial effects of captopril administration on the recuperating post-ischemic kidney were no longer evident. Concurrently, ACE inhibition exacerbated intrarenal hypoxia and accelerated oxidative stress, indicating that renal adaptation to some consequences of ischemia does require bioavailability of RAS components.
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Affiliation(s)
- Shai Efrati
- Research & Development Unit, Assaf Harofeh Medical Center, Zerifin 70300, Tel Aviv University, Israel.
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Mitazaki S, Honma S, Suto M, Kato N, Hiraiwa K, Yoshida M, Abe S. Interleukin-6 plays a protective role in development of cisplatin-induced acute renal failure through upregulation of anti-oxidative stress factors. Life Sci 2011; 88:1142-8. [PMID: 21570986 DOI: 10.1016/j.lfs.2011.04.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 04/20/2011] [Indexed: 11/28/2022]
Abstract
AIMS Cisplatin, a major chemotherapeutic agent, accumulates in proximal tubules of the kidneys and causes acute renal failure dose-dependently. We previously reported that cisplatin induced more severe renal dysfunction in interleukin-6 (IL-6) knockout (IL-6(-/-)) mice than in wild-type (WT) mice. Expression of a pro-apoptotic protein was significantly increased with cisplatin in IL-6(-/-) mice compared to that in WT mice. IL-6, locally expressed in renal tubular cells after cisplatin administration, prevents the development of renal dysfunction at an early stage. In the present study, we focused on downstream signals of IL-6 and oxidative stress induced by cisplatin in order to evaluate the protective role of IL-6 in the development of acute renal failure. MAIN METHODS WT and IL-6(-/-) mice were given either cisplatin (30 mg/kg) or saline intraperitoneally. Blood and kidney samples were collected at 24h and 72 h after cisplatin administration. The changes in expression of 4-hydroxy-2-nonenal protein (4-HNE, oxidative stress marker) and cyclooxygenase-2 (cox-2), activities of superoxide dismutases and caspase-3, and phosphorylation of extracellular signal-regulated kinase (ERK) were examined. KEY FINDINGS Cisplatin increased the expression of 4-HNE and cox-2, and phosphorylation of ERK in IL-6(-/-) mice than in WT mice. On the other hand, activity of superoxide dismutase, an anti-oxidative enzyme, was significantly decreased in the kidney obtained from IL-6(-/-) mice after cisplatin administration. SIGNIFICANCE Our findings suggest that IL-6 plays a protective role in the development of cisplatin-induced acute renal failure through upregulation of anti-oxidative stress factors.
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Affiliation(s)
- Satoru Mitazaki
- Laboratory of Forensic Toxicology, Faculty of Pharmacy, Takasaki University of Health and Welfare, 60 Nakaorui-machi, Takasaki 370-0033, Japan
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Ferro CDO, Chagas VLA, de Oliveira MF, de Oliveira PL, Schanaider A. [Catalase activity in lung, kidney and small bowel non-ischemic in rats after intestinal reperfusion]. Rev Col Bras Cir 2010; 37:31-8. [PMID: 20414575 DOI: 10.1590/s0100-69912010000100008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Accepted: 03/09/2009] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE This study aimed to assess the catalase activity after ischemia and reperfusion and to study the changes of this antioxidant in organs located far from the initial insult. METHODS Eighteen Wistar rats were randomly divided into three groups. 1-Control, 2-Simulation and 3-Ischemia and Reperfusion. In the latter it was done an ischemia of the ileum for 60 minutes followed by reperfusion for 30 minutes. In group 2 only laparotomy was performed. From all animals it was taken segments of the reperfused and non reperfused intestine, as well of the right kidney and lung to be evaluated under light microscopy. Catalase activity was measured in spectrophotometer with a wavelength set to 240 nm. It was used Mann Whitney and Kruskal Wallis statistical tests. RESULTS There was a significant increase (p <0.05) in the catalase activity not only at small bowel ischemic and non-ischemic segments but also at lungs. However the enzymatic activity decreases in the kidney. In all organs studied at reperfusion group it was found a slight villi derangement, mild congestion and infiltration with inflammatory cells, and areas of pulmonary atelectasis. CONCLUSION The intestinal oxidative stress in rats causes biochemical changes at distance, with mobilization of antioxidant defense mechanisms in lung, non-ischemic intestinal segment and kidney, with early decrease in this last organ, however, with no relevant cellular damage.
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Affiliation(s)
- Camila de Oliveira Ferro
- Departamento de Cirurgia, Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, BR.
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Abstract
Endotoxemia caused by LPS is a life-threatening and inflammatory condition contributing to multiple organ failure. Viruses or bacteria require sialic acid (SA) for target-cell binding. We suggest that exogenous SA through masking or mediating the binding of LPS to the target cells may attenuate LPS-induced liver dysfunction and cecal ligation and puncture-induced shock. We found that SA can directly scavenge O2-, H2O2, and NO activity by a chemiluminescence analyzer and bind to LPS with high affinity using surface plasmon resonance. Intravenous SA significantly increased plasma SA concentration within 4 h. We then assessed the potential effect of SA on LPS-induced acute endotoxemia in the rat. Intravenous LPS (10-50 mg/kg) dose-dependently increased plasma endotoxin and reactive oxygen species in the blood, bile, and liver and increased plasma alanine aminotransferase and aspartate aminotransferase levels as well as TNF-alpha, monocyte chemoattractant protein 1, tissue inhibitor of metalloproteinase 1, IL-1beta, and IL-6 levels in the rats. Thirty minutes after LPS stimulation, SA decreased LPS-enhanced endotoxin level, oxidative stress, alanine aminotransferase and aspartate aminotransferase levels, and cytokine concentration and ameliorated histopathologic alteration in the liver. We found that SA increased LPS-depressed Mn-superoxide dismutase, CuZn-superoxide dismutase, and heat shock protein 70 and decreased LPS-enhanced iNOS and proapoptotic Bax protein expression in the liver by Western blot. Sialic acid was given after treatment to rats subjected to cecal ligation and puncture, and the hypotensive effect was blunted for 6 h. In conclusion, SA treatment can counteract LPS-enhanced acute endotoxemia and oxidative injury via a direct scavenging reactive oxygen species activity and neutralization potential.
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Asghar M, Chugh G, Lokhandwala MF. Inflammation compromises renal dopamine D1 receptor function in rats. Am J Physiol Renal Physiol 2009; 297:F1543-9. [PMID: 19794106 DOI: 10.1152/ajprenal.00366.2009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We tested the effects of inflammation on renal dopamine D1 receptor signaling cascade, a key pathway that maintains sodium homeostasis and blood pressure during increased salt intake. Inflammation was produced by administering lipopolysaccharide (LPS; 4 mg/kg ip) to rats provided without (normal salt) and with 1% NaCl in drinking water for 2 wk (high salt). Control rats had saline injection and received tap water. We found that LPS increased the levels of inflammatory cytokines, interleukin-6, and tumor necrosis factor-alpha in the rats given either normal- or high-salt intake. Also, these rats had higher levels of oxidative stress markers, malondialdehyde and nitrotyrosine, and lower levels of antioxidant enzyme superoxide dismutase in the renal proximal tubules (RPTs). The nuclear levels of transcription factors NF-kappaB increased and Nrf2 decreased in the RPTs in response to LPS in rats given normal and high salt. Furthermore, D1 receptor numbers, D1 receptor proteins, and D1 receptor agonist (SKF38393)-mediated (35)S-GTPgammaS binding decreased in the RPTs in these rats. The basal activities of Na-K-ATPase in the RPTs were similar in control and LPS-treated rats given normal and high salt. SKF38393 caused inhibition of Na-K-ATPase activity in the primary cultures of RPTs treated with vehicle but not in the cultures treated with LPS. Furthermore, LPS caused an increase in blood pressure in the rats given high salt but not in the rats given normal salt. These results suggest that LPS differentially regulates NF-kappaB and Nrf2, produces inflammation, decreases antioxidant enzyme, increases oxidative stress, and causes D1 receptor dysfunction in the RPTs. The LPS-induced dysfunction of renal D1 receptors alters salt handling and causes hypertension in rats during salt overload.
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Affiliation(s)
- Mohammad Asghar
- Heart and Kidney Institute, College of Pharmacy, Univeristy of Houston, Houston, TX 77204, USA.
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Sampath V, Radish AC, Eis AL, Broniowska K, Hogg N, Konduri GG. Attenuation of lipopolysaccharide-induced oxidative stress and apoptosis in fetal pulmonary artery endothelial cells by hypoxia. Free Radic Biol Med 2009; 46:663-71. [PMID: 19135525 PMCID: PMC2646363 DOI: 10.1016/j.freeradbiomed.2008.12.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 12/03/2008] [Accepted: 12/03/2008] [Indexed: 01/27/2023]
Abstract
Pulmonary vascular endothelial injury resulting from lipopolysaccharide (LPS) and oxygen toxicity contributes to vascular simplification seen in the lungs of premature infants with bronchopulmonary dysplasia. Whether the severity of endotoxin-induced endothelial injury is modulated by ambient oxygen tension (hypoxic intrauterine environment vs. hyperoxic postnatal environment) remains unknown. We posited that ovine fetal pulmonary artery endothelial cells (FPAEC) will be more resistant to LPS toxicity under hypoxic conditions (20-25 Torr) mimicking the fetal milieu. LPS (10 microg/ml) inhibited FPAEC proliferation and induced apoptosis under normoxic conditions (21% O(2)) in vitro. LPS-induced FPAEC apoptosis was attenuated in hypoxia (5% O(2)) and exacerbated by hyperoxia (55% O(2)). LPS increased intracellular superoxide formation, as measured by 2-hydroxyethidium (2-HE) formation, in FPAEC in normoxia and hypoxia. 2-HE formation in LPS-treated FPAEC increased in parallel with the severity of LPS-induced apoptosis in FPAEC, increasing from hypoxia to normoxia to hyperoxia. Differences in LPS-induced apoptosis between hypoxia and normoxia were abolished when LPS-treated FPAEC incubated in hypoxia were pretreated with menadione to increase superoxide production. Apocynin decreased 2-HE formation, and attenuated LPS-induced FPAEC apoptosis under normoxic conditions. We conclude that ambient oxygen concentration modulates the severity of LPS-mediated injury in FPAEC by regulating superoxide levels produced in response to LPS.
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Affiliation(s)
- Venkatesh Sampath
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, USA.
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Peng PH, Huang HS, Lee YJ, Chen YS, Ma MC. Novel role for the δ-opioid receptor in hypoxic preconditioning in rat retinas. J Neurochem 2009; 108:741-54. [DOI: 10.1111/j.1471-4159.2008.05807.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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29
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Current World Literature. Curr Opin Nephrol Hypertens 2009; 18:91-3. [DOI: 10.1097/mnh.0b013e32831fd875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yang CC, Chien CT, Wu MH, Ma MC, Chen CF. NMDA receptor blocker ameliorates ischemia-reperfusion-induced renal dysfunction in rat kidneys. Am J Physiol Renal Physiol 2008; 294:F1433-40. [DOI: 10.1152/ajprenal.00481.2007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
N-methyl-d-aspartate (NMDA) receptor activated by glutamate/glycine is located in the kidneys. The NMDA receptor subunit NR1 is increased in damaged renal tissue. This study explored the role of NMDA receptors in ischemia-reperfusion-induced renal dysfunction in rats. With Western blot analysis and renal functional assay, NMDA receptor expression was evaluated, as well as its functional role in female Wistar rat kidneys after 45 min of unilateral ischemia followed by 24 h of reperfusion. The effects of intrarenal NMDA receptor agonist and antagonist on renal blood flow (RBF), glomerular filtration rate (GFR), urine volume (UV), sodium (UNaV), and potassium (UKV) excretion were determined. NMDA NR1 was present in the glomeruli, brush-border membrane, and outer medulla but not in the cortex and inner medulla. Homogenous distribution of non-NMDA GluR2/3, sparse kainate KA1, and undetectable group I of metabotropic glutamate receptor were noted in the control kidneys. Ischemia-reperfusion kidneys showed enhanced renal NR1, but not NR2C and GluR2/3 expression, and were associated with decreased GFR/RBF and natriuretic/diuretic responses. Intrarenal NMDA agonists significantly reduced GFR, UV, UNaV, and UKV but had no effect on blood pressure and RBF in sham control and ischemia-reperfusion kidneys. NMDA antagonist d-2-amino-5-phosphonopentanoic acid (D-AP-5) treatment completely abolished NMDA-induced renal dysfunction. D-AP-5 treatment significantly ameliorated ischemia-reperfusion-induced glomerular and tubular dysfunction by restoring decreased GFR, UV, and UNaV levels. Ischemia-reperfusion upregulates renal NMDA NR1 receptor expression, leading to reduced glomerular and tubular function in the kidneys. The NMDA antagonist can ameliorate ischemia-reperfusion-induced renal dysfunction.
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Lund DD, Brooks RM, Faraci FM, Heistad DD. Role of angiotensin II in endothelial dysfunction induced by lipopolysaccharide in mice. Am J Physiol Heart Circ Physiol 2007; 293:H3726-31. [PMID: 17965276 DOI: 10.1152/ajpheart.01116.2007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Endotoxin [or lipopolysaccharide (LPS)] increases levels of superoxide in blood vessels and impairs vasomotor function. Angiotensin II plays an important role in the generation of superoxide in several disease states, including hypertension and heart failure. The goal of this study was to determine whether the activation of the renin-angiotensin system contributes to oxidative stress and endothelial dysfunction after endotoxin. We examined the effects of enalapril (an angiotensin-converting enzyme inhibitor) or L-158809 (an angiotensin receptor blocker) on increases of superoxide and vasomotor dysfunction in mice treated with LPS. C57BL/6 mice were treated with either enalapril (60 mg.kg(-1).day(-1)) or L-158809 (30 mg.kg(-1).day(-1)) for 4 days. After the third day, LPS (10-20 mg/kg) or vehicle was injected intraperitoneally, and one day later, vasomotor function of the aorta was examined in vitro. After precontraction with PGF(2alpha), the maximal responses to sodium nitroprusside were similar in the aorta from normal and LPS-treated mice. In contrast, the relaxation to acetylcholine was impaired after LPS (54 +/- 5% at 10(-5), mean +/- SE) compared with vessels treated with vehicle (88 +/- 1%; P < 0.05). Enalapril improved (P < 0.05) relaxation in response to acetylcholine to 81 +/- 6% after LPS. L-158809 also improved relaxation in response to acetylcholine to 77 +/- 4% after LPS. Superoxide (measured with lucigenin and hydroethidine) was increased (P < 0.05) in aorta after LPS, and levels were reduced (P < 0.05) following enalapril and L-158809. Thus, after LPS, enalapril and L-158809 reduce superoxide levels and improve relaxation to acetylcholine in the aorta. The findings suggest that activation of the renin-angiotensin system contributes importantly to oxidative stress and endothelial dysfunction after endotoxin.
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Affiliation(s)
- Donald D Lund
- Department of Internal Medicine, University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA
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Persson PB. The magic mountain or death in Venice: chronic hypoxia may alleviate oxidative stress in the kidney. J Physiol 2007; 582:1. [PMID: 17347261 PMCID: PMC2075278 DOI: 10.1113/jphysiol.2007.131219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Pontus B Persson
- Johannes-Müller-Institut für Physiologie, Universitätsmedizin, Berlin (Charité), Tucholskystr. 2, D-10117 Berlin, Germany.
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