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Koh ES, Chung S. Recent Update on Acute Kidney Injury-to-Chronic Kidney Disease Transition. Yonsei Med J 2024; 65:247-256. [PMID: 38653563 PMCID: PMC11045347 DOI: 10.3349/ymj.2023.0306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/27/2023] [Accepted: 01/23/2024] [Indexed: 04/25/2024] Open
Abstract
Acute kidney injury (AKI) is characterized by an abrupt decline of excretory kidney function. The incidence of AKI has increased in the past decades. Patients diagnosed with AKI often undergo diverse clinical trajectories, such as early or late recovery, relapses, and even a potential transition from AKI to chronic kidney disease (CKD). Although recent clinical studies have demonstrated a strong association between AKI and progression of CKD, our understanding of the complex relationship between AKI and CKD is still evolving. No cohort study has succeeded in painting a comprehensive picture of these multi-faceted pathways. To address this lack of understanding, the idea of acute kidney disease (AKD) has recently been proposed. This presents a new perspective to pinpoint a period of heightened vulnerability following AKI, during which a patient could witness a substantial decline in glomerular filtration rate, ultimately leading to CKD transition. Although AKI is included in a range of kidney conditions collectively known as AKD, spanning from mild and self-limiting to severe and persistent, AKD can also occur without a rapid onset usually seen in AKI, such as when kidney dysfunction slowly evolves. In the present review, we summarize the most recent findings about AKD, explore the current state of biomarker discovery related to AKD, discuss the latest insights into pathophysiological underpinnings of AKI to CKD transition, and reflect on therapeutic challenges and opportunities that lie ahead.
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Affiliation(s)
- Eun Sil Koh
- Division of Nephrology, Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Sungjin Chung
- Division of Nephrology, Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
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2
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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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3
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Zhang L, Chen F, Dong J, Wang R, Bi G, Xu D, Zhang Y, Deng Y, Lin W, Yang Z, Cao W. HDAC3 aberration-incurred GPX4 suppression drives renal ferroptosis and AKI-CKD progression. Redox Biol 2023; 68:102939. [PMID: 37890360 PMCID: PMC10638610 DOI: 10.1016/j.redox.2023.102939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
Acute kidney injury (AKI) progression to chronic kidney disease (CKD) represents a unique renal disease setting characterized by early renal cellular injury and regulated cell death, and later renal fibrosis, of which the critical role and nature of ferroptosis are only partially understood. Here, we report that renal tubular epithelial ferroptosis caused by HDAC3 (histone deacetylase 3) aberration and the resultant GPX4 suppression drives AKI-CKD progression. In mouse models of AKI-CKD transition induced by nephrotoxic aristolochic acid (AA) and folic acid (FA), renal tubular epithelial ferroptosis occurred early that coincided with preferential HDAC3 elevation and marked suppression of a core anti-ferroptosis enzyme GPX4 (glutathione peroxidase 4). Intriguingly, genetic Hdac3 knockout or administration of a HDAC3-selective inhibitor RGFP966 effectively mitigated the GPX4 suppression, ferroptosis and the fibrosis-associated renal functional loss. In cultured tubular epithelial cells, HDAC3 over-expression or inhibition inversely affected GPX4 abundances. Further analysis revealed that Gpx4 promoter contains a typical binding motif of transcription factor KLF5 (Kruppel-like factor 5). HDAC3 and KLF5 inducibly associated and bound to Gpx4 promoter upon AA treatment, leading to local histone hypoacetylation and GPX4 transactivation inhibition, which was blocked by RGFP966 and a KLF5 inhibitor ML264, respectively, suggesting that KLF5 co-regulated the HDAC3-incurred Gpx4 transcription inhibition. More importantly, in AKI-CKD mice receiving a GPX4 inactivator RSL3, the anti-ferroptosis and renoprotective effects of RGFP966 were largely abrogated, indicating that GPX4 is an essential downstream mediator of the HDAC3 aberration and renal ferroptosis during AKI-CKD transition. Together, our study identified a critical epigenetic pathway of ferroptosis during AKI-CKD transition and suggested that the strategies preserving GPX4 by HDAC3 inhibition are potentially effective to reduce renal ferroptosis and slow AKI-CKD progression.
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Affiliation(s)
- Lijun Zhang
- Yancheng Medical Research Center of Nanjing University Medical School, Department of Central Laboratory, Yancheng First Hospital, Affiliated Hospital of Nanjing University Medical School, The First People's Hospital of Yancheng, Yancheng, China; Nanjing University Medical School, Jiangsu Key Lab of Molecular Medicine, Nanjing, China
| | - Fang Chen
- Yancheng Medical Research Center of Nanjing University Medical School, Department of Central Laboratory, Yancheng First Hospital, Affiliated Hospital of Nanjing University Medical School, The First People's Hospital of Yancheng, Yancheng, China
| | - Jian Dong
- Nanjing University Medical School, Jiangsu Key Lab of Molecular Medicine, Nanjing, China
| | - Rong Wang
- Yangzhou Precision Research Institute of Kidney Disease, Department of Nephrology, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Guangyu Bi
- Yangzhou Precision Research Institute of Kidney Disease, Department of Nephrology, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Daoliang Xu
- Yangzhou Precision Research Institute of Kidney Disease, Department of Nephrology, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Yingwei Zhang
- Department of Respirology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China
| | - Yijun Deng
- Yancheng Medical Research Center of Nanjing University Medical School, Department of Central Laboratory, Yancheng First Hospital, Affiliated Hospital of Nanjing University Medical School, The First People's Hospital of Yancheng, Yancheng, China
| | - Wenjun Lin
- Department of Nephrology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Zhongzhou Yang
- Nanjing University Medical School, Jiangsu Key Lab of Molecular Medicine, Nanjing, China.
| | - Wangsen Cao
- Yancheng Medical Research Center of Nanjing University Medical School, Department of Central Laboratory, Yancheng First Hospital, Affiliated Hospital of Nanjing University Medical School, The First People's Hospital of Yancheng, Yancheng, China; Nanjing University Medical School, Jiangsu Key Lab of Molecular Medicine, Nanjing, China; Yangzhou Precision Research Institute of Kidney Disease, Department of Nephrology, Northern Jiangsu People's Hospital, Yangzhou, China.
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4
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André C, Bodeau S, Kamel S, Bennis Y, Caillard P. The AKI-to-CKD Transition: The Role of Uremic Toxins. Int J Mol Sci 2023; 24:16152. [PMID: 38003343 PMCID: PMC10671582 DOI: 10.3390/ijms242216152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/31/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
After acute kidney injury (AKI), renal function continues to deteriorate in some patients. In a pro-inflammatory and profibrotic environment, the proximal tubules are subject to maladaptive repair. In the AKI-to-CKD transition, impaired recovery from AKI reduces tubular and glomerular filtration and leads to chronic kidney disease (CKD). Reduced kidney secretion capacity is characterized by the plasma accumulation of biologically active molecules, referred to as uremic toxins (UTs). These toxins have a role in the development of neurological, cardiovascular, bone, and renal complications of CKD. However, UTs might also cause CKD as well as be the consequence. Recent studies have shown that these molecules accumulate early in AKI and contribute to the establishment of this pro-inflammatory and profibrotic environment in the kidney. The objective of the present work was to review the mechanisms of UT toxicity that potentially contribute to the AKI-to-CKD transition in each renal compartment.
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Affiliation(s)
- Camille André
- Department of Clinical Pharmacology, Amiens Medical Center, 80000 Amiens, France; (S.B.); (Y.B.)
- GRAP Laboratory, INSERM UMR 1247, University of Picardy Jules Verne, 80000 Amiens, France
| | - Sandra Bodeau
- Department of Clinical Pharmacology, Amiens Medical Center, 80000 Amiens, France; (S.B.); (Y.B.)
- MP3CV Laboratory, UR UPJV 7517, University of Picardy Jules Verne, 80000 Amiens, France; (S.K.); (P.C.)
| | - Saïd Kamel
- MP3CV Laboratory, UR UPJV 7517, University of Picardy Jules Verne, 80000 Amiens, France; (S.K.); (P.C.)
- Department of Clinical Biochemistry, Amiens Medical Center, 80000 Amiens, France
| | - Youssef Bennis
- Department of Clinical Pharmacology, Amiens Medical Center, 80000 Amiens, France; (S.B.); (Y.B.)
- MP3CV Laboratory, UR UPJV 7517, University of Picardy Jules Verne, 80000 Amiens, France; (S.K.); (P.C.)
| | - Pauline Caillard
- MP3CV Laboratory, UR UPJV 7517, University of Picardy Jules Verne, 80000 Amiens, France; (S.K.); (P.C.)
- Department of Nephrology, Dialysis and Transplantation, Amiens Medical Center, 80000 Amiens, France
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5
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Liu X, Hu J, Liao G, Liu D, Zhou S, Zhang J, Liao J, Guo Z, Li Y, Yang S, Li S, Chen H, Guo Y, Li M, Fan L, Li L, Zhao M, Liu Y. The role of regulatory T cells in the pathogenesis of acute kidney injury. J Cell Mol Med 2023; 27:3202-3212. [PMID: 37667551 PMCID: PMC10568672 DOI: 10.1111/jcmm.17771] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/28/2023] [Accepted: 05/04/2023] [Indexed: 09/06/2023] Open
Abstract
The incidence of acute kidney injury (AKI) is on the rise and is associated with high mortality; however, there are currently few effective treatments. Moreover, the relationship between Tregs and other components of the immune microenvironment (IME) in the pathogenesis of AKI remains unclear. We downloaded four publicly accessible AKI datasets, GSE61739, GSE67401, GSE19130, GSE81741, GSE19288 and GSE106993 from the gene expression omnibus (GEO) database. Additionally, we gathered two kidney single-cell sequencing (scRNA-seq) samples from the Department of Organ Transplantation at Zhujiang Hospital of Southern Medical University to investigate chronic kidney transplant rejection (CKTR). Moreover, we also collected three samples of normal kidney tissue from GSE131685. By analysing the differences in immune cells between the AKI and Non-AKI groups, we discovered that the Non-AKI group contained a significantly greater number of Tregs than the AKI group. Additionally, the activation of signalling pathways, such as inflammatory molecules secretion, immune response, glycolytic metabolism, NOTCH, FGF, NF-κB and TLR4, was significantly greater in the AKI group than in the Non-AKI group. Additionally, analysis of single-cell sequencing data revealed that Tregs in patients with chronic kidney rejection and in normal kidney tissue have distinct biology, including immune activation, cytokine production, and activation fractions of signalling pathways such as NOTCH and TLR4. In this study, we found significant differences in the IME between AKI and Non-AKI, including differences in Tregs cells and activation levels of biologically significant signalling pathways. Tregs were associated with lower activity of signalling pathways such as inflammatory response, inflammatory molecule secretion, immune activation, glycolysis.
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Affiliation(s)
- Xiaoyou Liu
- Department of Organ transplantationThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouChina
| | - Jianmin Hu
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Guorong Liao
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Ding Liu
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Song Zhou
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Jie Zhang
- Department of Organ transplantationThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouChina
| | - Jun Liao
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Zefeng Guo
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Yuzhu Li
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Siqiang Yang
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Shichao Li
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Hua Chen
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Ying Guo
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Min Li
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Lipei Fan
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Liuyang Li
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Ming Zhao
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
| | - Yongguang Liu
- Department of Organ transplantationZhujiang Hospital of the Southern Medical UniversityGuangzhouChina
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6
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Cheng AS, Li X. The Potential Biotherapeutic Targets of Contrast-Induced Acute Kidney Injury. Int J Mol Sci 2023; 24:8254. [PMID: 37175958 PMCID: PMC10178966 DOI: 10.3390/ijms24098254] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/27/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
Contrast-induced acute kidney injury (CI-AKI) is manifested by an abrupt decline in kidney function as a consequence of intravascular exposure to contrast media. With the increased applicability of medical imaging and interventional procedures that utilize contrast media for clinical diagnosis, CI-AKI is becoming the leading cause of renal dysfunction. The pathophysiological mechanism associated with CI-AKI involves renal medullary hypoxia, the direct toxicity of contrast agents, oxidative stress, apoptosis, inflammation, and epigenetic regulation. To date, there is no effective therapy for CI-AKI, except for the development of strategies that could reduce the toxicity profiles of contrast media. While most of these strategies have failed, evidence has shown that the proper use of personalized hydration, contrast medium, and high-dose statins may reduce the occurrence of CI-AKI. However, adequate risk predication and attempts to develop preventive strategies can be considered as the key determinants that can help eliminate CI-AKI. Additionally, a deeper understanding of the pathophysiological mechanism of CI-AKI is crucial to uncover molecular targets for the prevention of CI-AKI. This review has taken a step further to solidify the current known molecular mechanisms of CI-AKI and elaborate the biomarkers that are used to detect early-stage CI-AKI. On this foundation, this review will analyze the molecular targets relating to apoptosis, inflammation, oxidative stress, and epigenetics, and, thus, provide a strong rationale for therapeutic intervention in the prevention of CI-AKI.
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Affiliation(s)
- Alice Shasha Cheng
- Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA;
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Xiaogang Li
- Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA;
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
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7
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Nesovic Ostojic J, Zivotic M, Kovacevic S, Ivanov M, Brkic P, Mihailovic-Stanojevic N, Karanovic D, Vajic UJ, Miloradovic Z, Jovovic D, Radojevic Skodric S. Immunohistochemical Pattern of Histone H2A Variant Expression in an Experimental Model of Ischemia-Reperfusion-Induced Acute Kidney Injury. Int J Mol Sci 2023; 24:ijms24098085. [PMID: 37175793 PMCID: PMC10179385 DOI: 10.3390/ijms24098085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/20/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
Ischemia-reperfusion injury (IRI) is a frequent cause of AKI, resulting in vasoconstriction, cellular dysfunction, inflammation and the induction of oxidative stress. DNA damage, including physical DNA strand breaks, is also a potential consequence of renal IRI. The histone H2A variants, primary H2AX and H2AZ participate in DNA damage response pathways to promote genome stability. The aim of this study was to evaluate the immunohistochemical pattern of histone H2A variants' (H2AX, γH2AX(S139), H2AXY142ph and H2AZ) expression in an experimental model of ischemia-reperfusion-induced acute kidney injury in spontaneously hypertensive rats. Comparing the immunohistochemical nuclear expression of γH2AX(S139) and H2AXY142ph in AKI, we observed that there is an inverse ratio of these two histone H2AX variants. If we follow different regions from the subcapsular structures to the medulla, there is an increasing extent gradient in the nuclear expression of H2AXY142ph, accompanied by a decreasing nuclear expression of γH2AX. In addition, we observed that different structures dominated when γH2AX and H2AXY142ph expression levels were compared. γH2AX was expressed only in the proximal tubule, with the exception of when they were dilated. In the medulla, H2AXY142ph is predominantly expressed in the loop of Henle and the collecting ducts. Our results show moderate sporadic nuclear H2AZ expression mainly in the cells of the distal tubules and the collecting ducts that were surrounded by dilated tubules with PAS (periodic acid-Schiff stain)-positive casts. These findings may indicate the degree of DNA damage, followed by postischemic AKI, with potential clinical and prognostic implications regarding this condition.
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Affiliation(s)
- Jelena Nesovic Ostojic
- Department of Pathological Physiology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - Maja Zivotic
- Institute of Pathology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - Sanjin Kovacevic
- Department of Pathological Physiology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - Milan Ivanov
- Institute for Medical Research, Department of Cardiovascular Physiology, National Institute of Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia
| | - Predrag Brkic
- Department of Medical Physiology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
| | - Nevena Mihailovic-Stanojevic
- Institute for Medical Research, Department of Cardiovascular Physiology, National Institute of Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia
| | - Danijela Karanovic
- Institute for Medical Research, Department of Cardiovascular Physiology, National Institute of Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia
| | - Una Jovana Vajic
- Institute for Medical Research, Department of Cardiovascular Physiology, National Institute of Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia
| | - Zoran Miloradovic
- Institute for Medical Research, Department of Cardiovascular Physiology, National Institute of Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia
| | - Djurdjica Jovovic
- Institute for Medical Research, Department of Cardiovascular Physiology, National Institute of Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia
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Luan J, Kopp JB, Zhou H. N6-methyladenine RNA Methylation Epigenetic Modification and Kidney Diseases. Kidney Int Rep 2022; 8:36-50. [PMID: 36644366 PMCID: PMC9831943 DOI: 10.1016/j.ekir.2022.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 10/01/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
RNA methylation modification is a rapidly developing field in epigenetics. N6-methyladensine (m6A) is the most common internal modification in eukaryotic mRNA. m6A group regulates RNA splicing, stability, translocation, and translation. Enzymes catalyzing this process were termed as writers, erasers, and readers. Recent studies have focused on exploring the role of RNA methylation in human diseases. RNA methylation modifications, particularly m6A, play important roles in the pathogenesis of kidney diseases. In this review, we provide a brief description of m6A and summarize the impact of m6A on acute and chronic kidney disease (CKD) and possible future study directions for this research.
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Affiliation(s)
- Junjun Luan
- Department of Nephrology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Jeffrey B. Kopp
- Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases/National Institutes of Health, Bethesda, Maryland, USA,Jeffrey B. Kopp, Kidney Disease Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases/National Institutes of Health, 10 Center Drive, 3N116, Bethesda, Maryland 20892-1268, USA.
| | - Hua Zhou
- Department of Nephrology, Shengjing Hospital of China Medical University, Shenyang, China,Correspondence: Hua Zhou, Shengjing Hospital of China Medical University, No.36 Sanhao Street, Shenyang, Liaoning 110004, China.
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9
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Zhou W, Chen MM, Liu HL, Si ZL, Wu WH, Jiang H, Wang LX, Vaziri ND, An XF, Su K, Chen C, Tan NH, Zhang ZH. Dihydroartemisinin suppresses renal fibrosis in mice by inhibiting DNA-methyltransferase 1 and increasing Klotho. Acta Pharmacol Sin 2022; 43:2609-2623. [PMID: 35347248 PMCID: PMC9525601 DOI: 10.1038/s41401-022-00898-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 03/06/2022] [Indexed: 02/07/2023] Open
Abstract
Renal fibrosis is an unavoidable end result of all forms of progressive chronic kidney diseases (CKD). Discovery of efficacious drugs against renal fibrosis is in crucial need. In a preliminary study we found that a derivative of artemisinin, dihydroartemisinin (DHA), exerted strong renoprotection, and reversed renal fibrosis in adenine-induced CKD mouse model. In this study we investigated the anti-fibrotic mechanisms of DHA, particularly its specific target in renal cells. Renal fibrosis was induced in mice by unilateral ureteral obstruction (UUO) or oral administration of adenine (80 mg · kg-1), the mice received DHA (30 mg · kg-1 · d-1, i.g.) for 14 or 21 days, respectively. We showed that DHA administration markedly attenuated the inflammation and fibrotic responses in the kidneys and significantly improved the renal function in both the renal fibrosis mouse models. In adenine-treated mice, DHA was more effective than 5-azacytidine against renal fibrosis. The anti-fibrotic effects of DHA were also observed in TGF-β1-treated HK-2 cells. In order to determine the target protein of DHA, we conducted pull-down technology coupled with shotgun proteomics using a small-molecule probe based on the structure of DHA (biotin-DHA). As a results, DNA methyltransferase 1 (DNMT1) was identified as the anti-fibrotic target of DHA in 3 different types of renal cell lines (HK-2, HEK293 and 3T3). We demonstrated that DHA directly bound to Asn 1529 and Thr 1528 of DNMT1 with a Kd value of 8.18 μM. In primary mouse renal tubular cells, we showed that DHA (10 μM) promoted DNMT1 degradation via the ubiquitin-proteasome pathway. DHA-reduced DNMT1 expression effectively reversed Klotho promoter hypermethylation, which led to the reversal of Klotho protein loss in the kidney of UUO mice. This subsequently resulted in inhibition of the Wnt/β-catenin and TGF-β/Smad signaling pathways and consequently conferred renoprotection in the animals. Knockdown of Klotho abolished the renoprotective effect of DHA in UUO mice. Our study reveals a novel pharmacological activity for DHA, i.e., renoprotection. DHA exhibits this effect by targeting DNMT1 to reverse Klotho repression. This study provides an evidence for the possible clinical application of DHA in the treatment of renal fibrosis.
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Affiliation(s)
- Wei Zhou
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Min-Min Chen
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Hui-Ling Liu
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Zi-Lin Si
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Wen-Hui Wu
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Hong Jiang
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Lin-Xiao Wang
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Nosratola D Vaziri
- Division of Nephrology and Hypertension, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Xiao-Fei An
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Ke Su
- Department of Nephrology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Cheng Chen
- Department of Nephrology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Ning-Hua Tan
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Zhi-Hao Zhang
- State Key Laboratory of Natural Medicines, Department of TCMs Pharmaceuticals, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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10
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Murray KO, Clanton TL, Horowitz M. Epigenetic responses to heat: From adaptation to maladaptation. Exp Physiol 2022; 107:1144-1158. [PMID: 35413138 PMCID: PMC9529784 DOI: 10.1113/ep090143] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 03/25/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the topic of this review? This review outlines the history of research on epigenetic adaptations to heat exposure. The perspective taken is that adaptations reflect properties of hormesis, whereby low, repeated doses of heat induce adaptation (acclimation/acclimatization); whereas brief, life-threatening exposures can induce maladaptive responses. What advances does it highlight? The epigenetic mechanisms underlying acclimation/acclimatization comprise specific molecular programmes on histones that regulate heat shock proteins transcriptionally and protect the organism from subsequent heat exposures, even after long delays. The epigenetic signalling underlying maladaptive responses might rely, in part, on extensive changes in DNA methylation that are sustained over time and might contribute to later health challenges. ABSTRACT Epigenetics plays a strong role in molecular adaptations to heat by producing a molecular memory of past environmental exposures. Moderate heat, over long periods of time, induces an 'adaptive' epigenetic memory, resulting in a condition of 'resilience' to future heat exposures or cross-tolerance to other forms of toxic stress. In contrast, intense, life-threatening heat exposures, such as severe heat stroke, can result in a 'maladaptive' epigenetic memory that can place an organism at risk of later health complications. These cellular memories are coded by post-translational modifications of histones on the nucleosomes and/or by changes in DNA methylation. They operate by inducing changes in the level of gene transcription and therefore phenotype. The adaptive response to heat acclimation functions, in part, by facilitating transcription of essential heat shock proteins and exhibits a biphasic short programme (maintaining DNA integrity, followed by a long-term consolidation). The latter accelerates acclimation responses after de-acclimation. Although less studied, the maladaptive responses to heat stroke appear to be coded in long-lasting changes in DNA methylation near the promoter region of genes involved with basic cell function. Whether these memories are also encoded in histone modifications is not yet known. There is considerable evidence that both adaptive and maladaptive epigenetic responses to heat can be inherited, although most evidence comes from lower organisms. Future challenges include understanding the signalling mechanisms responsible and discovering new ways to promote adaptive responses while suppressing maladaptive responses to heat, as all life forms adapt to life on a warming planet.
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Affiliation(s)
- Kevin O. Murray
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Thomas L. Clanton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Michal Horowitz
- Laboratory of Environmental Physiology, Faculty of Dentistry, The Hebrew University of Jerusalem, Jerusalem, Israel
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11
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Deng J, Wu Z, He Y, Lin L, Tan W, Yang J. Interaction Between Intrinsic Renal Cells and Immune Cells in the Progression of Acute Kidney Injury. Front Med (Lausanne) 2022; 9:954574. [PMID: 35872775 PMCID: PMC9300888 DOI: 10.3389/fmed.2022.954574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 06/15/2022] [Indexed: 11/25/2022] Open
Abstract
A growing number of studies have confirmed that immune cells play various key roles in the pathophysiology of acute kidney injury (AKI) development. After the resident immune cells and intrinsic renal cells are damaged by ischemia and hypoxia, drugs and toxins, more immune cells will be recruited to infiltrate through the release of chemokines, while the intrinsic cells promote macrophage polarity conversion, and the immune cells will promote various programmed deaths, phenotypic conversion and cycle arrest of the intrinsic cells, ultimately leading to renal impairment and fibrosis. In the complex and dynamic immune microenvironment of AKI, the bidirectional interaction between immune cells and intrinsic renal cells affects the prognosis of the kidney and the progression of fibrosis, and determines the ultimate fate of the kidney.
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Affiliation(s)
- Junhui Deng
- The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhifen Wu
- The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yun He
- The Fifth People's Hospital of Chongqing, Chongqing, China
| | - Lirong Lin
- The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wei Tan
- The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jurong Yang
- The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
- *Correspondence: Jurong Yang ;
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12
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Association of severity and mortality of Covid-19 cases among acute kidney injury and sexual dimorphism. Mol Biol Rep 2022; 49:6753-6762. [PMID: 35249167 PMCID: PMC8898193 DOI: 10.1007/s11033-022-07308-1] [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: 12/28/2021] [Accepted: 02/24/2022] [Indexed: 11/26/2022]
Abstract
Introduction The outbreak of coronavirus disease 2019 (Covid-19) severely impacted global health and economic status. The native receptor-ligand interaction of Angiotensin-converting enzyme 2 (ACE2) and S protein induces host cell pathogenesis via immunosuppression. Material and Methods The emerging evidence reports the sex disparity in Covid-19 induced mortality rate which affects abundantly men population. Although the biological interaction of Covid-19 with receptor upregulates the viral genome protein interactions and initiates the predictive multiorgan failure followed by acute kidney injury (AKI) in Covid-19 infected male population. Conclusion Besides, the knowledge and lessons learned from the study depict that cellular and molecular links may explain the risk and severity of Covid-19 and AKI in the male population and lead to management of Covid-19 induced AKI. Therefore, this review explored the pathways associated with the pathogenesis of two diseased conditions with sex disparity.
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13
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Satalkar V, Swamy KV. Pathophysiology of acute kidney injury on a molecular level: A brief review. MGM JOURNAL OF MEDICAL SCIENCES 2022. [DOI: 10.4103/mgmj.mgmj_161_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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14
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Leu JG, Su WH, Chen YC, Liang YJ. Hydralazine attenuates renal inflammation in diabetic rats with ischemia/reperfusion acute kidney injury. Eur J Pharmacol 2021; 910:174468. [PMID: 34478692 DOI: 10.1016/j.ejphar.2021.174468] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/24/2021] [Accepted: 08/30/2021] [Indexed: 01/23/2023]
Abstract
Acute kidney injury (AKI) is one of the major complications with increased oxidative stress and inflammation in diabetic patients. Hyperglycemia stimulates the formation of advanced glycation end products (AGEs). However, hyperglycemia directly triggers the interaction between AGEs and transmembrane AGEs receptors (RAGE), which enhances oxidative stress and increases the production of inflammatory substances. Therefore, diabetes plays a pivotal role in kidney injury. Hydralazine, a vasodilator and antihypertensive drug, was found to have the ability to reduce ROS, oxidative stress, and inflammation. We applied Hydralazine co-culture with AGEs in rat mesangial cells (RMC) and to renal ischemia/reperfusion(I/R) injury models in streptozotocin-induced diabetic rats. Hydralazine significantly decreased AGEs-induced RAGE, iNOS, and COX-2 expressions in RMC. Compared to the diabetic with AKI group, hydralazine decreased inflammation-related protein, and JAK2, STAT3 signaling in rat kidney tissue. Our studies indicate that Hydralazine has the potential to become a beneficial drug in the treatment of diabetic acute kidney injury.
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Affiliation(s)
- Jyh-Gang Leu
- Fu-Jen Catholic University School of Medicine, New Taipei City, Taiwan, ROC; Division of Nephrology, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, ROC; Institute of Pharmacology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Wei-Hsiang Su
- Department and Institute of Life Science, Fu-Jen Catholic University, New Taipei City, Taiwan, ROC
| | - Yu-Cheng Chen
- Division of Nephrology, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, ROC; Institute of Pharmacology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yao-Jen Liang
- Department and Institute of Life Science, Fu-Jen Catholic University, New Taipei City, Taiwan, ROC.
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15
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Li Z, Li N. Epigenetic Modification Drives Acute Kidney Injury-to-Chronic Kidney Disease Progression. Nephron Clin Pract 2021; 145:737-747. [PMID: 34419948 DOI: 10.1159/000517073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/05/2021] [Indexed: 11/19/2022] Open
Abstract
Acute kidney injury (AKI) is a common clinical critical disease. Due to its high morbidity, increasing risk of complications, high mortality rate, and high medical costs, it has become a global concern for human health problems. Initially, researchers believed that kidneys have a strong ability to regenerate and repair, but studies over the past 20 years have found that kidneys damaged by AKI are often incomplete or even unable to repair. Even when serum creatinine returns to baseline levels, renal structural damage persists for a long time, leading to the development of chronic kidney disease (CKD). The mechanism of AKI-to-CKD transition has not been fully elucidated. As an important regulator of gene expression, epigenetic modifications, such as histone modification, DNA methylation, and noncoding RNAs, may play an important role in this process. Alterations in epigenetic modification are induced by hypoxia, thus promoting the expression of inflammatory factor-related genes and collagen secretion. This review elaborated the role of epigenetic modifications in AKI-to-CKD progression, the diagnostic value of epigenetic modifications biomarkers in AKI chronic outcome, and the potential role of targeting epigenetic modifications in the prevention and treatment of AKI to CKD, in order to provide ideas for the subsequent establishment of targeted therapeutic strategies to prevent the progression of renal tubular-interstitial fibrosis.
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Affiliation(s)
- Zhenzhen Li
- Medical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ningning Li
- Department of Pathology, Henan Medical College, Zhengzhou, China
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16
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Portilla D, Xavier S. Role of intracellular complement activation in kidney fibrosis. Br J Pharmacol 2021; 178:2880-2891. [PMID: 33555070 DOI: 10.1111/bph.15408] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/22/2021] [Accepted: 02/02/2021] [Indexed: 02/06/2023] Open
Abstract
Increased expression of complement C1r, C1s and C3 in kidney cells plays an important role in the pathogenesis of kidney fibrosis. Our studies suggest that activation of complement in kidney cells with increased generation of C3 and its fragments occurs by activation of classical and alternative pathways. Single nuclei RNA sequencing studies in kidney tissue from unilateral ureteral obstruction mice show that increased synthesis of complement C3 and C5 occurs primarily in renal tubular epithelial cells (proximal and distal), while increased expression of complement receptors C3ar1 and C5ar1 occurs in interstitial cells including immune cells like monocytes/macrophages suggesting compartmentalization of complement components during kidney injury. Although global deletion of C3 and macrophage ablation prevent inflammation and reduced kidney tissue scarring, the development of mice with cell-specific deletion of complement components and their regulators could bring further insights into the mechanisms by which intracellular complement activation leads to fibrosis and progressive kidney disease. LINKED ARTICLES: This article is part of a themed issue on Canonical and non-canonical functions of the complement system in health and disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.14/issuetoc.
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Affiliation(s)
- Didier Portilla
- Department of Medicine and Center for Immunity and Regenerative Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Sandhya Xavier
- Department of Medicine and Center for Immunity and Regenerative Medicine, University of Virginia, Charlottesville, Virginia, USA
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17
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Vegfa promoter gene hypermethylation at HIF1α binding site is an early contributor to CKD progression after renal ischemia. Sci Rep 2021; 11:8769. [PMID: 33888767 PMCID: PMC8062449 DOI: 10.1038/s41598-021-88000-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 04/06/2021] [Indexed: 11/08/2022] Open
Abstract
Chronic hypoxia is a major contributor to Chronic Kidney Disease (CKD) after Acute Kidney Injury (AKI). However, the temporal relation between the acute insult and maladaptive renal response to hypoxia remains unclear. In this study, we analyzed the time-course of renal hemodynamics, oxidative stress, inflammation, and fibrosis, as well as epigenetic modifications, with focus on HIF1α/VEGF signaling, in the AKI to CKD transition. Sham-operated, right nephrectomy (UNx), and UNx plus renal ischemia (IR + UNx) groups of rats were included and studied at 1, 2, 3, or 4 months. The IR + UNx group developed CKD characterized by progressive proteinuria, renal dysfunction, tubular proliferation, and fibrosis. At first month post-ischemia, there was a twofold significant increase in oxidative stress and reduction in global DNA methylation that was maintained throughout the study. Hif1α and Vegfa expression were depressed in the first and second-months post-ischemia, and then Hif1α but not Vegfa expression was recovered. Interestingly, hypermethylation of the Vegfa promoter gene at the HIF1α binding site was found, since early stages of the CKD progression. Our findings suggest that renal hypoperfusion, inefficient hypoxic response, increased oxidative stress, DNA hypomethylation, and, Vegfa promoter gene hypermethylation at HIF1α binding site, are early determinants of AKI-to-CKD transition.
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18
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Lin Y, Yin P, Zhu Z, Peng Y, Li M, Li J, Liang L, Yu X. Epigenome-wide association study and network analysis for IgA Nephropathy from CD19 + B-cell in Chinese Population. Epigenetics 2021; 16:1283-1294. [PMID: 33319642 DOI: 10.1080/15592294.2020.1861171] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
IgA nephropathy (IgAN) is the most common primary glomerular disease in China and worldwide. The proliferation of B cells is known to be associated with both risk and prognosis of IgAN, but the epigenetic mechanism underlying this association is unknown. In this study we carried out the first Epigenome-wide Association Study (EWAS) by using the latest Infinium Methylation EPIC BeadChip on 184 B cell-specific samples (92 case/control pairs) for Chinese IgAN population. After rigorous data normalization and residual batch effect correction, linear mixed effect model was used to detect methylation CpG sites associated with IgAN adjusting for age, gender and smoking. False discovery rate (FDR) less than 10% was used to account for multiple testing. Weighted gene co-methylation networks were generated to identify gene modules highly correlated with IgAN. A permutation test was performed to account for the potential effect of overfitting. After adjusting clinical covariates and potential technical batch effects, three CpGs corresponding to PCDH17, TERT, WDR82 genes and three in the intergenic regions passed the genome-wide significant threshold. Methylation network analysis identified an additional IgAN associated gene module, containing 72 significant CpGs including GALNT6, IQSEC1, CDC16 and SYS1, involved in the pathway related to tubular atrophy/interstitial fibrosis of IgAN. These results suggested important DNA methylation and gene targets in CD19+ B cells for the pathogenesis of IgAN.
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Affiliation(s)
- Yifei Lin
- Precision Medicine Center, Department of Urology, Medical Device Regulatory Research and Evaluation Center, West China Hospital, Sichuan University, Chengdu, China.,Program in Genetic Epidemiology and Statistical Genetics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Peiran Yin
- Department of Nephrology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Zhaozhong Zhu
- Program in Genetic Epidemiology and Statistical Genetics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Yuan Peng
- Department of Nephrology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Ming Li
- Department of Nephrology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Jun Li
- Program in Genetic Epidemiology and Statistical Genetics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA.,Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Liming Liang
- Program in Genetic Epidemiology and Statistical Genetics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Xueqing Yu
- Department of Nephrology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.,Department of Nephrology, Guangdong Provincial People's Hospital, Guangzhou, China
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19
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Sheng L, Zhuang S. New Insights Into the Role and Mechanism of Partial Epithelial-Mesenchymal Transition in Kidney Fibrosis. Front Physiol 2020; 11:569322. [PMID: 33041867 PMCID: PMC7522479 DOI: 10.3389/fphys.2020.569322] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/26/2020] [Indexed: 12/14/2022] Open
Abstract
Epithelial-mesenchymal transition (EMT) is described as the process in which injured renal tubular epithelial cells undergo a phenotype change, acquiring mesenchymal characteristics and morphing into fibroblasts. Initially, it was widely thought of as a critical mechanism of fibrogenesis underlying chronic kidney disease. However, evidence that renal tubular epithelial cells can cross the basement membrane and become fibroblasts in the renal interstitium is rare, leading to debate about the existence of EMT. Recent research has demonstrated that after injury, renal tubular epithelial cells acquire mesenchymal characteristics and the ability to produce a variety of profibrotic factors and cytokines, but remain attached to the basement membrane. On this basis, a new concept of “partial epithelial-mesenchymal transition (pEMT)” was proposed to explain the contribution of renal epithelial cells to renal fibrogenesis. In this review, we discuss the concept of pEMT and the most recent findings related to this process, including cell cycle arrest, metabolic alternation of epithelial cells, infiltration of immune cells, epigenetic regulation as well as the novel signaling pathways that mediate this disturbed epithelial-mesenchymal communication. A deeper understanding of the role and the mechanism of pEMT may help in developing novel therapies to prevent and halt fibrosis in kidney disease.
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Affiliation(s)
- Lili Sheng
- Department of Nephrology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shougang Zhuang
- Department of Nephrology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.,Department of Medicine, Rhode Island Hospital and Alpert Medical School, Brown University, Providence, RI, United States
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20
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Complement component C5a induces aberrant epigenetic modifications in renal tubular epithelial cells accelerating senescence by Wnt4/βcatenin signaling after ischemia/reperfusion injury. Aging (Albany NY) 2020; 11:4382-4406. [PMID: 31284268 PMCID: PMC6660044 DOI: 10.18632/aging.102059] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 06/24/2019] [Indexed: 12/30/2022]
Abstract
Epigenetic mechanisms, such as DNA methylation, affect tubular maladaptive response after Acute Kidney Injury (AKI) and accelerate renal aging. Upon ischemia/reperfusion (I/R) injury, Complement activation leads to C5a release that mediates damage; however, little is known about the effect of C5a-C5a Receptor (C5aR) interaction in Renal Tubular Epithelial Cells (RTEC). Through a whole-genome DNA methylation analysis in cultured RTEC, we found that C5a induced aberrant methylation, particularly in regions involved in cell cycle control, DNA damage and Wnt signaling. The most represented genes were BCL9, CYP1B1 and CDK6. C5a stimulation of RTEC led to up-regulation of SA-β Gal and cell cycle arrest markers such as p53 and p21. C5a increased also IL-6, MCP-1 and CTGF gene expression, consistent with SASP development. In accordance, in a swine model of renal I/R injury, we found the increased expression of Wnt4 and βcatenin correlating with SA-β Gal, p21, p16 and IL-6 positivity. Administration of Complement Inhibitor (C1-Inh), antagonized SASP by reducing SA-β Gal, p21, p16, IL-6 and abrogating Wnt4/βcatenin activation. Thus, C5a affects the DNA methylation of genes involved in tubular senescence. Targeting epigenetic programs and Complement may offer novels strategies to protect tubular cells from accelerated aging and to counteract progression to Chronic Kidney Disease
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21
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LeBleu VS, Neilson EG. Origin and functional heterogeneity of fibroblasts. FASEB J 2020; 34:3519-3536. [PMID: 32037627 DOI: 10.1096/fj.201903188r] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 01/21/2020] [Accepted: 01/23/2020] [Indexed: 12/12/2022]
Abstract
The inherent plasticity and resiliency of fibroblasts make this cell type a conventional tool for basic research. But where do they come from, are all fibroblasts the same, and how do they function in disease? The first fibroblast lineages in mammalian development emerge from the ooze of primary mesenchyme during gastrulation. They are cells that efficiently create and negotiate the extracellular matrix of the mesoderm in order to migrate and meet their developmental fate. Mature fibroblasts in epithelial tissues live in the interstitial spaces between basement membranes that spatially delimit complex organ structures. While the function of resident fibroblasts in healthy tissues is largely conjecture, the accumulation of fibroblasts in pathologic lesions offers insight into biologic mechanisms that control their function; fibroblasts are poised to coordinate fibrogenesis in tissue injury, neoplasia, and aging. Here, we examine the developmental origin and plasticity of fibroblasts, their molecular and functional definitions, the epigenetic control underlying their identity and activation, and the evolution of their immune regulatory functions. These topics are reviewed through the lens of fate mapping using genetically engineered mouse models and from the perspective of single-cell RNA sequencing. Recent observations suggest dynamic and heterogeneous functions for fibroblasts that underscore their complex molecular signatures and utility in injured tissues.
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Affiliation(s)
- Valerie S LeBleu
- Departments of Medicine and Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Eric G Neilson
- Departments of Medicine and Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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22
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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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23
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Fontecha-Barriuso M, Martin-Sanchez D, Ruiz-Andres O, Poveda J, Sanchez-Niño MD, Valiño-Rivas L, Ruiz-Ortega M, Ortiz A, Sanz AB. Targeting epigenetic DNA and histone modifications to treat kidney disease. Nephrol Dial Transplant 2019. [PMID: 29534238 DOI: 10.1093/ndt/gfy009] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Epigenetics refers to heritable changes in gene expression patterns not caused by an altered nucleotide sequence, and includes non-coding RNAs and covalent modifications of DNA and histones. This review focuses on functional evidence for the involvement of DNA and histone epigenetic modifications in the pathogenesis of kidney disease and the potential therapeutic implications. There is evidence of activation of epigenetic regulatory mechanisms in acute kidney injury (AKI), chronic kidney disease (CKD) and the AKI-to-CKD transition of diverse aetiologies, including ischaemia-reperfusion injury, nephrotoxicity, ureteral obstruction, diabetes, glomerulonephritis and polycystic kidney disease. A beneficial in vivo effect over preclinical kidney injury has been reported for drugs that decrease DNA methylation by either inhibiting DNA methylation (e.g. 5-azacytidine and decitabine) or activating DNA demethylation (e.g. hydralazine), decrease histone methylation by inhibiting histone methyltransferases, increase histone acetylation by inhibiting histone deacetylases (HDACs, e.g. valproic acid, vorinostat, entinostat), increase histone crotonylation (crotonate) or interfere with histone modification readers [e.g. inhibits of bromodomain and extra-terminal proteins (BET)]. Most preclinical studies addressed CKD or the AKI-to-CKD transition. Crotonate administration protected from nephrotoxic AKI, but evidence is conflicting on DNA methylation inhibitors for preclinical AKI. Several drugs targeting epigenetic regulators are in clinical development or use, most of them for malignancy. The BET inhibitor apabetalone is in Phase 3 trials for atherosclerosis, kidney function being a secondary endpoint, but nephrotoxicity was reported for DNA and HDAC inhibitors. While research into epigenetic modulators may provide novel therapies for kidney disease, caution should be exercised based on the clinical nephrotoxicity of some drugs.
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Affiliation(s)
- Miguel Fontecha-Barriuso
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Diego Martin-Sanchez
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Olga Ruiz-Andres
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Jonay Poveda
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Maria Dolores Sanchez-Niño
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Lara Valiño-Rivas
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Marta Ruiz-Ortega
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Alberto Ortiz
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
| | - Ana Belén Sanz
- Research Institute IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain.,IRSIN, Madrid, Spain.,REDINREN, Madrid, Spain
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24
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Xavier S, Sahu RK, Bontha SV, Mass V, Taylor RP, Megyesi J, Thielens NM, Portilla D. Complement C1r serine protease contributes to kidney fibrosis. Am J Physiol Renal Physiol 2019; 317:F1293-F1304. [PMID: 31509012 DOI: 10.1152/ajprenal.00357.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We have previously reported that complement activation precedes the development of kidney fibrosis; however, little is known about the cellular mechanisms involved in this transition. We hypothesized that increased expression of C1 complex protease C1r, the initiator of complement activation, contributes to tubulointerstitial fibrosis and tested this idea in mice with global deletion of C1r. Although expression of C1r in untreated wild-type (WT) mice was higher in the liver compared with kidney tissue, administration of folic acid (FA) led to upregulation of C1r mRNA and protein levels only in kidney tissue. Immunohistochemistry and in situ hybridization experiments localized increased expression of C1r and C1s proteases to renal tubular epithelial cells. C1r-null mice had reduced acute tubular injury and inflammation measured 2 days after FA administration compared with WT mice. C1r deletion reduced expression of C1s, C3 fragment formation, and organ fibrosis measured 14 days after FA administration. Differential gene expression performed in kidney tissue demonstrated that C1r-null mice had reduced expression of genes associated with the acute phase response, complement, proliferation of connective tissue cells (e.g., platelet-derived growth factor receptor-β), and reduced expression of genes associated with inflammation compared with FA-treated WT mice. In vitro experiments in renal epithelial cells demonstrated that C1s expression is dependent on increased C1r expression and that interferon-γ induces the expression of these two proteases. We conclude that increased expression of C1 complex proteases is associated with increased tissue inflammation and complement C3 formation and represents an important pathogenic mechanism leading to FA-mediated tubulointerstitial fibrosis.
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Affiliation(s)
- Sandhya Xavier
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia, Charlottesville, Virginia
| | - Ranjit K Sahu
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia, Charlottesville, Virginia
| | - Sai Vineela Bontha
- Methodist University of Tennessee Transplant Institute, Memphis, Tennessee
| | - Valeria Mass
- Methodist University of Tennessee Transplant Institute, Memphis, Tennessee
| | - Ronald P Taylor
- Department of Biochemistry, University of Virginia, Charlottesville, Virginia
| | - Judit Megyesi
- University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Nicole M Thielens
- University of Grenoble Alpes, Centre National de la Recherche Scientifique, Commissariat à l'énergie Atomique et aux Énergies Alternatives, L'Institut de Biologie Structurale, Grenoble, France
| | - Didier Portilla
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia, Charlottesville, Virginia.,Salem Veterans Affairs Medical Center, Salem, Virginia
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25
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Situmorang GR, Sheerin NS. Ischaemia reperfusion injury: mechanisms of progression to chronic graft dysfunction. Pediatr Nephrol 2019; 34:951-963. [PMID: 29603016 PMCID: PMC6477994 DOI: 10.1007/s00467-018-3940-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/18/2018] [Accepted: 03/02/2018] [Indexed: 12/18/2022]
Abstract
The increasing use of extended criteria organs to meet the demand for kidney transplantation raises an important question of how the severity of early ischaemic injury influences long-term outcomes. Significant acute ischaemic kidney injury is associated with delayed graft function, increased immune-associated events and, ultimately, earlier deterioration of graft function. A comprehensive understanding of immediate molecular events that ensue post-ischaemia and their potential long-term consequences are key to the discovery of novel therapeutic targets. Acute ischaemic injury primarily affects tubular structure and function. Depending on the severity and persistence of the insult, this may resolve completely, leading to restoration of normal function, or be sustained, resulting in persistent renal impairment and progressive functional loss. Long-term effects of acute renal ischaemia are mediated by several mechanisms including hypoxia, HIF-1 activation, endothelial dysfunction leading to vascular rarefaction, sustained pro-inflammatory stimuli involving innate and adaptive immune responses, failure of tubular cells to recover and epigenetic changes. This review describes the biological relevance and interaction of these mechanisms based on currently available evidence.
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Affiliation(s)
- Gerhard R Situmorang
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
- Urology Department, Faculty of Medicine Universitas Indonesia - Cipto Mangunkusumo Hospital, Jakarta, 10430, Indonesia
| | - Neil S Sheerin
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
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26
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Chou YH, Chu TS, Lin SL. Role of renin-angiotensin system in acute kidney injury-chronic kidney disease transition. Nephrology (Carlton) 2019; 23 Suppl 4:121-125. [PMID: 30298669 DOI: 10.1111/nep.13467] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2018] [Indexed: 12/23/2022]
Abstract
Acute kidney injury (AKI) can increase the risk of developing incident chronic kidney disease (CKD). The severity, frequency and duration of AKI are crucial predictors of poor renal outcome. A repair process after AKI can be adaptive and kidney recovers completely after a mild injury. However, severe injury will lead to a maladaptive repair, which frequently progresses to nephron loss, vascular rarefaction, chronic inflammation and fibrosis. Although different mechanisms underlying AKI-CKD transition have been extensively discussed, no definite intervention has been proved effective to block or to retard the transition until recently. In CKD, renin-angiotensin system (RAS) inhibitor has been proved effective to slow down disease progression. Furthermore, RAS needs to be highlighted again in AKI-CKD transition because recent animal studies have shown the activation of intra-renal RAS after AKI, and RAS blockade can reduce the ensuing CKD and mortality. In patients with the complete renal recovery after AKI, administration of RAS inhibitor is associated with reduced risk of subsequent CKD as well. In this article, we will demonstrate the role of RAS in AKI-CKD transition comprehensively. We will then emphasize the promising effect of RAS inhibitor on CKD prevention in patients recovering from AKI based on evidence from the bench to clinical research. All of these discussions will contribute to the establishment of reliable monitoring and therapeutic strategies for patients with functional recovery from AKI who can be most easily ignored.
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Affiliation(s)
- Yu-Hsiang Chou
- Renal Division, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.,Department of Internal Medicine, National Taiwan University Hospital Jin-Shan Branch, New Taipei City, Taiwan.,Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Tzong-Shinn Chu
- Renal Division, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Shuei-Liong Lin
- Renal Division, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.,Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan.,Department of Integrated Diagnostics and Therapeutics, National Taiwan University Hospital, Taipei, Taiwan.,Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
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27
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Sharifian R, Okamura DM, Denisenko O, Zager RA, Johnson A, Gharib SA, Bomsztyk K. Distinct patterns of transcriptional and epigenetic alterations characterize acute and chronic kidney injury. Sci Rep 2018; 8:17870. [PMID: 30552397 PMCID: PMC6294783 DOI: 10.1038/s41598-018-35943-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 11/12/2018] [Indexed: 02/07/2023] Open
Abstract
Acute kidney injury (AKI) and chronic kidney disease (CKD) are considered early and late phases of a pathologic continuum of interconnected disease states. Although changes in gene expression patterns have recently been elucidated for the transition of AKI to CKD, the epigenetic regulation of key kidney injury related genes remains poorly understood. We used multiplex RT-qPCR, ChIP-qPCR and integrative analysis to compare transcriptional and epigenetic changes at renal disease-associated genes across mouse AKI and CKD models. These studies showed that: (i) there are subsets of genes with distinct transcriptional and epigenetically profiles shared by AKI and CKD but also subsets that are specific to either the early or late stages of renal injury; (ii) differences in expression of a small number of genes is sufficient to distinguish AKI from CKD; (iii) transcription plays a key role in the upregulation of both AKI and CKD genes while post-transcriptional regulation appears to play a more significant role in decreased expression of both AKI and CKD genes; and (iv) subsets of transcriptionally upregulated genes share epigenetic similarities while downregulated genes do not. Collectively, our study suggests that identified common transcriptional and epigenetic profiles of kidney injury loci could be exploited for therapeutic targeting in AKI and CKD.
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Affiliation(s)
- Roya Sharifian
- UW Medicine South Lake Union, University of Washington, Seattle, WA, 98109, USA
| | - Daryl M Okamura
- Seattle Children's Research Institute, Center for Developmental Biology & Regenerative Medicine, University of Washington, Seattle, WA, 98105, USA
| | - Oleg Denisenko
- UW Medicine South Lake Union, University of Washington, Seattle, WA, 98109, USA
| | - Richard A Zager
- The Fred Hutchinson Cancer Research Center Seattle, Seattle, WA, 98109, USA
| | - Ali Johnson
- The Fred Hutchinson Cancer Research Center Seattle, Seattle, WA, 98109, USA
| | - Sina A Gharib
- UW Medicine South Lake Union, University of Washington, Seattle, WA, 98109, USA.,Computational Medicine Core, Center for Lung Biology, University of Washington, Seattle, WA, 98109, USA
| | - Karol Bomsztyk
- UW Medicine South Lake Union, University of Washington, Seattle, WA, 98109, USA.
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28
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Virzì GM, Clementi A, Brocca A, de Cal M, Ronco C. Epigenetics: a potential key mechanism involved in the pathogenesis of cardiorenal syndromes. J Nephrol 2017; 31:333-341. [PMID: 28780716 DOI: 10.1007/s40620-017-0425-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 07/26/2017] [Indexed: 12/15/2022]
Abstract
Epigenetics is defined as the heritable changes in gene expression patterns which are not directly encoded by modifications in the nucleotide DNA sequence of the genome, including higher order chromatin organization, DNA methylation, cytosine modifications, covalent histone tail modifications, and short non-coding RNA molecules. Recently, much attention has been paid to the role and the function of epigenetics and epimutations in the cellular and subcellular pathways and in the regulation of genes in the setting of both kidney and cardiovascular disease. Indeed, deregulation of histone alterations has been highlighted in a large spectrum of renal and cardiac disease, including chronic and acute renal injury, renal and cardiac fibrosis, cardiac hypertrophy and failure, kidney congenital anomalies, renal hypoxia, and diabetic renal complications. Nevertheless, the role of epigenetics in the pathogenesis and pathophysiology of cardiorenal syndromes is currently underexplored. Given the significant clinical relevance of heart-kidney crosstalk, efforts in the research for new action mechanisms concurrently operating in both pathologies are thus of maximum interest. This review focuses on epigenetic mechanisms involved in heart and kidney disease, and their possible role in the setting of cardiorenal syndromes.
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Affiliation(s)
- Grazia Maria Virzì
- Department of Nephrology, Dialysis and Transplant, San Bortolo Hospital, Via Rodolfi, 37, 36100, Vicenza, Italy. .,IRRIV-International Renal Research Institute Vicenza, Vicenza, Italy.
| | - Anna Clementi
- IRRIV-International Renal Research Institute Vicenza, Vicenza, Italy.,Department of Nephrology and Dialysis, San Giovanni di Dio Hospital, Agrigento, Italy
| | - Alessandra Brocca
- Department of Nephrology, Dialysis and Transplant, San Bortolo Hospital, Via Rodolfi, 37, 36100, Vicenza, Italy.,IRRIV-International Renal Research Institute Vicenza, Vicenza, Italy.,Department of Medicine DIMED, University of Padova Medical School, Padua, Italy
| | - Massimo de Cal
- Department of Nephrology, Dialysis and Transplant, San Bortolo Hospital, Via Rodolfi, 37, 36100, Vicenza, Italy.,IRRIV-International Renal Research Institute Vicenza, Vicenza, Italy
| | - Claudio Ronco
- Department of Nephrology, Dialysis and Transplant, San Bortolo Hospital, Via Rodolfi, 37, 36100, Vicenza, Italy.,IRRIV-International Renal Research Institute Vicenza, Vicenza, Italy
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29
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Novel insights into acute kidney injury-chronic kidney disease continuum and the role of renin-angiotensin system. J Formos Med Assoc 2017; 116:652-659. [PMID: 28615146 DOI: 10.1016/j.jfma.2017.04.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 04/25/2017] [Indexed: 12/11/2022] Open
Abstract
Acute kidney injury (AKI) is an independent risk factor for chronic kidney disease (CKD). If injury is mild, a repair process can be adaptive and lead to complete renal recovery. However, severe injury will be accompanied by a maladaptive repair which usually leads to nephron loss, fibrosis, vascular rarefaction, and chronic inflammation. Although various mechanisms underlying AKI-CKD transition have been explored, no intervention has been proved effective to block the transition until very recently. A lack of consensus for monitoring renal function and defining renal recovery after AKI should be the reasons for the slow advance in the discovery of a timely pharmacologic treatment to block AKI-CKD transition. Recently, animal studies have shown the activation of renin-angiotensin system (RAS) after AKI. In patients with complete renal recovery after AKI defined as the decrease of serum creatinine level to within 0.3 mg/dL above the baseline, administration of RAS inhibitor can prevent the ensuing CKD. In this review, we will discuss the renal recovery after AKI and the mechanisms underlying AKI-CKD transition. We will then highlight the promising effect of RAS inhibitor on CKD prevention in patients with complete renal recovery from AKI based on the recent clinical evidence.
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30
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Tang PMK, Tang PCT, Chung JYF, Lan HY. TGF-β1 signaling in kidney disease: From Smads to long non-coding RNAs. Noncoding RNA Res 2017; 2:68-73. [PMID: 30159422 PMCID: PMC6096420 DOI: 10.1016/j.ncrna.2017.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/14/2017] [Accepted: 04/06/2017] [Indexed: 01/07/2023] Open
Abstract
Transforming growth factor-β1 (TGF-β1) has an essential role in the development of kidney diseases. However, targeting TGF-β1 is not a good strategy for fibrotic diseases due to its multifunctional characteristic in physiology. A precise therapeutic target maybe identified by further resolving the underlying TGF-β1 driven mechanisms in renal inflammation and fibrosis. Smad signaling is uncovered as a key pathway of TGF-β1-mediated renal injury, where Smad3 is hyper-activated but Smad7 is suppressed. Mechanistic studies revealed that TGF-β1/Smad3 is capable of promoting renal inflammation and fibrosis via regulating non-coding RNAs. More importantly, involvement of disease- and tissue-specific TGF-β1-dependent long non-coding RNAs (lncRNA) have been recently recognized in a number of kidney diseases. In this review, current understanding of TGF-β1 driven lncRNAs in the pathogenesis of kidney injury, diabetic nephropathy and renal cell carcinoma will be intensively discussed.
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Affiliation(s)
- Patrick Ming-Kuen Tang
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong SAR, China
- Li Ka Shing Institute of Health Sciences, CUHK-Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Philip Chiu-Tsun Tang
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Jeff Yat-Fai Chung
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Hui-Yao Lan
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong SAR, China
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong SAR, China
- Li Ka Shing Institute of Health Sciences, CUHK-Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong SAR, China
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31
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Zhou B, Mu J, Gong Y, Lu C, Zhao Y, He T, Qin Z. Brd4 inhibition attenuates unilateral ureteral obstruction-induced fibrosis by blocking TGF-β-mediated Nox4 expression. Redox Biol 2016; 11:390-402. [PMID: 28063381 PMCID: PMC5219604 DOI: 10.1016/j.redox.2016.12.031] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 12/20/2016] [Accepted: 12/29/2016] [Indexed: 01/09/2023] Open
Abstract
Uncovering new therapeutic targets for renal fibrosis holds promise for the treatment of chronic kidney diseases. Bromodomain and extra-terminal (BET) protein inhibitors have been shown to effectively ameliorate pathological fibrotic responses. However, the pharmacological effects and underlying mechanisms of these inhibitors in renal fibrosis remain elusive. In this study, we determined that the inhibition of Brd4, a BET family member, with a selective potent chemical inhibitor, JQ1, could prevent the development of renal fibrosis and block the progression of fibrosis in rats that have undergone unilateral ureteral obstruction (UUO). Inhibiting Brd4 with either JQ1 or genetic knockdown resulted in decreased expression of fibrotic genes such as α-smooth muscle actin, collagen IV and fibronectin both in UUO-induced fibrosis and upon TGF-β1 stimulation in HK-2 cells. Brd4 inhibition also suppressed the oxidative stress induced by UUO in vivo or by TGF-β1 in HK-2 cells. Moreover, Nox4, which is constitutively active in renal cells and is involved in the generation of hydrogen peroxide, was up-regulated during UUO-mediated fibrosis and induced by TGF-β1 in HK-2 cells, and this up-regulation could be blunted by Brd4 inhibition. Consistently, Nox4-mediated ROS generation and fibrotic gene expression were attenuated upon Brd4 inhibition. Further, the transcriptional activity of Nox4 was suppressed by JQ1 or siRNA against Brd4. Additionally, Smad3 and ERK1/2 phosphorylation, which are upstream signals of Nox4 expression, were inhibited both in JQ1-administered UUO rats and Brd4-inhibited HK-2 cells. In conclusion, these results indicated that the inhibition of Brd4 might protect against renal fibrosis by blocking the TGF-β-Nox4-ROS-fibrosis axis, suggesting that Brd4 could be a promising therapeutic target. Brd4 was up-regulated in the progression of renal fibrosis. Brd4 inhibitor JQ1 prevented renal fibrosis and delayed the fibrotic progression. Brd4 inhibition blocked TGF-β1-induced oxidative stress and fibrosis through Nox4. Brd4 regulated Nox4 expression via Smad and ERK pathways.
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Affiliation(s)
- Baoshang Zhou
- Department of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Jiao Mu
- Department of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Yi Gong
- Department of Nephrology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
| | - Caibao Lu
- Department of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Youguang Zhao
- Department of Urology, Chengdu Military General Hospital, Chengdu 610083, China
| | - Ting He
- Department of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Zhexue Qin
- Department of Cardiology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China.
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32
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Chen Z, Li Y, Xu H, Ma F, Li J, Zhao L, Xu Y. Elevated ischaemia-associated lysyl oxidase activity in delayed graft failure 6-12 months after renal transplantation. Exp Physiol 2016; 102:282-287. [PMID: 28024102 DOI: 10.1113/ep085444] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 11/02/2016] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? What potential biochemical changes are associated with renal parenchyma 6-12 months after renal transplantation and delayed graft failure? What is the main finding and its importance? Tissue fibrosis, mediated by tissue ischaemia-induced induction of hypoxia-inducible factor-1α and fibronectin and consequent activation of lysyl oxidase, is a major underlying pathophysiological mechanism that contributes to delayed graft failure several months after renal transplantation. The present investigation was undertaken to evaluate the potential biochemical changes associated with renal parenchyma 6-12 months after renal transplantation and delayed graft failure. Serum concentrations of transforming growth factor-β in these subjects always remained elevated. In addition, examination of tissue from needle biopsies confirmed that there were consistent changes in the enzyme lysyl oxidase, which functions as an amine oxidase, modifies lysine residues on collagen and cross-links in a process of modulation of the extracellular matrix. Parenchymal levels of hypoxia-inducible factor-1α and fibronectin were elevated, as detected by Western blotting. These findings indicate an ongoing ischaemic insult, which might result from increased tissue fibrosis or, in some cases, might be additive with pre-existing pathophysiological factors that constrain proper renal haemodynamics. Thus, increased lysyl oxidase activity, which we assayed, is a potential unfavourable mechanism occurring in these kidneys that are undergoing failure and probably causes increased fibrosis within the organ and causes ischaemia, renovascular hypertension and a cascade leading to renal dysfunction and failure.
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Affiliation(s)
- Zhi Chen
- Department of Nephrology, The First Hospital of the Jilin University, Changchun, 130021, Jilin, China
| | - Yiyang Li
- Department of Gynecology, The First Hospital of the Jilin University, Changchun, 130021, Jilin, China
| | - Hongmei Xu
- Department of Obstetrics, The First Hospital of the Jilin University, Changchun, 130021, Jilin, China
| | - Fuzhe Ma
- Department of Nephrology, The First Hospital of the Jilin University, Changchun, 130021, Jilin, China
| | - Jia Li
- Department of Nephrology, The First Hospital of the Jilin University, Changchun, 130021, Jilin, China
| | - Lei Zhao
- Department of Molecular Physiology and Biophysics, Holden Comprehensive Cancer Center, University of Iowa Carver College of Medicine, Iowa city, IA, 52242, USA
| | - Ying Xu
- Department of Nephrology, The First Hospital of the Jilin University, Changchun, 130021, Jilin, China
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33
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Zhang Q, Yin S, Liu L, Liu Z, Cao W. Rhein reversal of DNA hypermethylation-associated Klotho suppression ameliorates renal fibrosis in mice. Sci Rep 2016; 6:34597. [PMID: 27703201 PMCID: PMC5050540 DOI: 10.1038/srep34597] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 09/15/2016] [Indexed: 11/15/2022] Open
Abstract
Renal fibrosis is the hallmark of chronic kidney diseases (CKD) and its development and progression are significantly affected by epigenetic modifications. Rhein, a plant-derived anthraquinone, displays strong anti-fibrosis properties, but its protective mode of action remains incompletely understood. Here we explore the mechanism of Rhein anti-renal fibrosis by investigating its regulation of Klotho, a known renal anti-fibrotic protein whose suppression after renal injury reportedly involves aberrant DNA methylation. We report that Rhein is an impressive up-regulator of Klotho and it markedly reversed Klotho down-regulation in unilateral ureteral occlusion-induced fibrotic kidney. Further examinations revealed that Klotho loss in fibrotic kidney is associated with Klotho promoter hypermethylation due to aberrant methyltransferase 1 and 3a expressions. However, Rhein significantly corrected all these epigenetic alterations and subsequently alleviated pro-fibrotic protein expression and renal fibrosis, whereas Klotho knockdown via RNA interferences largely abrogated the anti-renal fibrotic effects of Rhein, suggesting that Rhein epigenetic reversal of Klotho loss represents a critical mode of action that confers Rhein’s anti- renal fibrotic functions. Altogether our studies uncover a novel hypomethylating character of Rhein in preventing Klotho loss and renal fibrosis, and demonstrate the efficacy of Klotho-targeted epigenetic intervention in potential treatment of renal fibrosis-associated kidney diseases.
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Affiliation(s)
- Qin Zhang
- Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, 210016, China.,National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Shasha Yin
- The Key lab of Jiangsu molecular Medicine, Nanjing University School of Medicine, Nanjing, 210093, China
| | - Lin Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Zhihong Liu
- Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, 210016, China.,National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China
| | - Wangsen Cao
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210016, China.,The Key lab of Jiangsu molecular Medicine, Nanjing University School of Medicine, Nanjing, 210093, China
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34
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Zhang Q, Liu L, Lin W, Yin S, Duan A, Liu Z, Cao W. Rhein reverses Klotho repression via promoter demethylation and protects against kidney and bone injuries in mice with chronic kidney disease. Kidney Int 2016; 91:144-156. [PMID: 27692562 DOI: 10.1016/j.kint.2016.07.040] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 07/19/2016] [Accepted: 07/28/2016] [Indexed: 12/26/2022]
Abstract
Rhein is an anthraquinone compound isolated from the medicinal plant rhubarb and mainly used in the clinical treatment of diabetic nephropathy. Rhein exhibits various renoprotective functions, but the underlying mechanisms are not fully determined. However, its renoprotective properties recapitulate the role of Klotho, a renal-specific antiaging protein critical for maintaining kidney homeostasis. Here we explored the connections between rhein renoprotection and Klotho in a mouse model of adenine-induced chronic kidney disease. In addition to being an impressive Klotho upregulator, rhein remarkably reversed renal Klotho deficiency in adenine-treated mice. This effect was associated with significant improvement in disturbed serum biochemistry, profibrogenic protein expression, and kidney and bone damage. Further investigation of the molecular basis of Klotho loss revealed that these kidneys displayed marked inductions of DNA methyltransferase DNMT1/DNMT3a and Klotho promoter hypermethylation, whereas rhein treatment effectively corrected these alterations. The renal protective effects of rhein were largely abolished when Klotho was knocked-down by RNA interferences, suggesting that rhein reversal of Klotho deficiency is essential for its renoprotective actions. Thus, our study clarifies how rhein regulation of Klotho expression contributes to its renoprotection and brings new insights into Klotho-targeted strategy for the treatment of kidney diseases of various etiologies.
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Affiliation(s)
- Qin Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China; The Key Lab of Jiangsu Molecular Medicine, Nanjing University School of Medicine, Nanjing, China; Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, China
| | - Lin Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Wenjun Lin
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Shasha Yin
- The Key Lab of Jiangsu Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Aiping Duan
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China; Division of Nephrology, Jinling Hospital, Southern Medical University, Nanjing, China.
| | - Wangsen Cao
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China; The Key Lab of Jiangsu Molecular Medicine, Nanjing University School of Medicine, Nanjing, China.
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35
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Ravindran S, Kuruvilla V, Wilbur K, Munusamy S. Nephroprotective Effects of Metformin in Diabetic Nephropathy. J Cell Physiol 2016; 232:731-742. [DOI: 10.1002/jcp.25598] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 12/22/2022]
Affiliation(s)
| | | | - Kerry Wilbur
- College of Pharmacy; Qatar University; Doha Qatar
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36
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Guo J, Guan Q, Liu X, Wang H, Gleave ME, Nguan CYC, Du C. Relationship of clusterin with renal inflammation and fibrosis after the recovery phase of ischemia-reperfusion injury. BMC Nephrol 2016; 17:133. [PMID: 27649757 PMCID: PMC5028988 DOI: 10.1186/s12882-016-0348-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 09/12/2016] [Indexed: 01/10/2023] Open
Abstract
Background Long-term outcomes after acute kidney injury (AKI) include incremental loss of function and progression towards chronic kidney disease (CKD); however, the pathogenesis of AKI to CKD remains largely unknown. Clusterin (CLU) is a chaperone-like protein that reduces ischemia-reperfusion injury (IRI) and enhances tissue repair after IRI in the kidney. This study investigated the role of CLU in the transition of IRI to renal fibrosis. Methods IRI was induced in the left kidneys of wild type (WT) C57BL/6J (B6) versus CLU knockout (KO) B6 mice by clamping the renal pedicles for 28 min at the body temperature of 32 °C. Tissue damage was examined by histology, infiltrate phenotypes by flow cytometry analysis, and fibrosis-related gene expression by PCR array. Results Reduction of kidney weight was induced by IRI, but was not affected by CLU KO. Both WT and KO kidneys had similar function with minimal cellular infiltration and fibrosis at day 14 of reperfusion. After 30 days, KO kidneys had greater loss in function than WT, indicated by the higher levels of both serum creatinine and BUN in KO mice, and exhibited more cellular infiltration (CD8 cells and macrophages), more tubular damage and more severe tissue fibrosis (glomerulopathy, interstitial fibrosis and vascular fibrosis). PCR array showed the association of CLU deficiency with up-regulation of CCL12, Col3a1, MMP9 and TIMP1 and down-regulation of EGF in these kidneys. Conclusion Our data suggest that CLU deficiency worsens renal inflammation and tissue fibrosis after IRI in the kidney, which may be mediated through multiple pathways. Electronic supplementary material The online version of this article (doi:10.1186/s12882-016-0348-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jia Guo
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.,Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Qiunong Guan
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Xiuheng Liu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Hao Wang
- Department of General Surgery, Tianjin Medical University General Hospital, Tianjin, China
| | - Martin E Gleave
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.,Vancouver Prostate Centre, Vancouver, BC, Canada
| | - Christopher Y C Nguan
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Caigan Du
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada. .,Department of Urologic Sciences, The University of British Columbia, VGH-Jack Bell Research Centre, 2660 Oak St, Vancouver, BC, V6H 3Z6, Canada.
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Virzì GM, Clementi A, Brocca A, de Cal M, Ronco C. Molecular and Genetic Mechanisms Involved in the Pathogenesis of Cardiorenal Cross Talk. Pathobiology 2016; 83:201-10. [DOI: 10.1159/000444502] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/04/2016] [Indexed: 11/19/2022] Open
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Abstract
Despite marked improvements in the survival of patients with severe lupus nephritis over the past 50 years, the rate of complete clinical remission after immune suppression therapy is <50% and renal impairment still occurs in 40% of affected patients. An appreciation of the factors that lead to the development of chronic kidney disease following acute or subacute renal injury in patients with systemic lupus erythematosus is beginning to emerge. Processes that contribute to end-stage renal injury include continuing inflammation, activation of intrinsic renal cells, cell stress and hypoxia, metabolic abnormalities, aberrant tissue repair and tissue fibrosis. A deeper understanding of these processes is leading to the development of novel or adjunctive therapies that could protect the kidney from the secondary non-immune consequences of acute injury. Approaches based on a molecular-proteomic-lipidomic classification of disease should yield new information about the functional basis of disease heterogeneity so that the most effective and least toxic treatment regimens can be formulated for individual patients.
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