1
|
Ren L, Cui H, Wang Y, Ju F, Cai Y, Gang X, Wang G. The role of lipotoxicity in kidney disease: From molecular mechanisms to therapeutic prospects. Biomed Pharmacother 2023; 161:114465. [PMID: 36870280 DOI: 10.1016/j.biopha.2023.114465] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/20/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
Lipotoxicity is the dysregulation of the lipid environment and/or intracellular composition that leads to accumulation of harmful lipids and ultimately to organelle dysfunction, abnormal activation of intracellular signaling pathways, chronic inflammation and cell death. It plays an important role in the development of acute kidney injury and chronic kidney disease, including diabetic nephropathy, obesity-related glomerulopathy, age-related kidney disease, polycystic kidney disease, and the like. However, the mechanisms of lipid overload and kidney injury remain poorly understood. Herein, we discuss two pivotal aspects of lipotoxic kidney injury. First, we analyzed the mechanism of lipid accumulation in the kidney. Accumulating data indicate that the mechanisms of lipid overload in different kidney diseases are inconsistent. Second, we summarize the multiple mechanisms by which lipotoxic species affect the kidney cell behavior, including oxidative stress, endoplasmic reticulum stress, mitochondrial dysfunction, dysregulated autophagy, and inflammation, highlighting the central role of oxidative stress. Blocking the molecular pathways of lipid accumulation in the kidney and the damage of the kidney by lipid overload may be potential therapeutic targets for kidney disease, and antioxidant drugs may play a pivotal role in the treatment of kidney disease in the future.
Collapse
Affiliation(s)
- Linan Ren
- Department of Endocrinology and Metabolism, First Hospital of Jilin University, Changchun 130021, Jilin, China; Institute of Translational Medicine, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Haiying Cui
- Department of Endocrinology and Metabolism, First Hospital of Jilin University, Changchun 130021, Jilin, China; Institute of Translational Medicine, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Yao Wang
- Department of Orthopedics, The Second Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Feng Ju
- Department of Orthopedics, Yuci District People's Hospital, Yuci 030600, Shanxi, China
| | - Yunjia Cai
- Department of Endocrinology and Metabolism, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Xiaokun Gang
- Department of Endocrinology and Metabolism, First Hospital of Jilin University, Changchun 130021, Jilin, China.
| | - Guixia Wang
- Department of Endocrinology and Metabolism, First Hospital of Jilin University, Changchun 130021, Jilin, China.
| |
Collapse
|
2
|
Zhao YB, Wei W, Lin XX, Chai YF, Jin H. The Role of Histone H3 Methylation in Acute Kidney Injury. Drug Des Devel Ther 2022; 16:2453-2461. [PMID: 35941926 PMCID: PMC9356748 DOI: 10.2147/dddt.s376673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/27/2022] [Indexed: 12/28/2022] Open
Abstract
Acute kidney injury (AKI) is a clinical syndrome in which kidney function declines sharply due to various reasons. Although the morbidity and mortality of AKI are high, the mechanism of occurrence and development of AKI has not been fully elucidated, and precise prevention and treatment measures are lacking. Epigenetics is a branch of genetics that provides a new perspective to explore the pathophysiology of AKI and renal repair. A large amount of literature shows that the methylation mechanism of H3 in histones is closely related to the development of kidney diseases. The sorting out of histone H3 methylation mechanism in AKI and kidney repair can help understand the pathophysiological process of the disease more deeply. It may also provide new ideas for diagnosing and treating of the disease.
Collapse
Affiliation(s)
- Yi-Bo Zhao
- Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, 300000, People’s Republic of China
| | - Wei Wei
- Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, 300000, People’s Republic of China
| | - Xiao-Xi Lin
- Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, 300000, People’s Republic of China
| | - Yan-Fen Chai
- Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, 300000, People’s Republic of China
| | - Heng Jin
- Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, 300000, People’s Republic of China
- Correspondence: Heng Jin; Yan-Fen Chai, Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, 300000, People’s Republic of China, Email ;
| |
Collapse
|
3
|
Cheng Y, Chen Y, Wang G, Liu P, Xie G, Jing H, Chen H, Fan Y, Wang M, Zhou J. Protein Methylation in Diabetic Kidney Disease. Front Med (Lausanne) 2022; 9:736006. [PMID: 35647002 PMCID: PMC9133329 DOI: 10.3389/fmed.2022.736006] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 03/07/2022] [Indexed: 11/13/2022] Open
Abstract
Chronic kidney disease (CKD) is defined by persistent urine aberrations, structural abnormalities, or impaired excretory renal function. Diabetes is the leading cause of CKD. Their common pathological manifestation is renal fibrosis. Approximately half of all patients with type 2 diabetes and one-third with type 1 diabetes will develop CKD. However, renal fibrosis mechanisms are still poorly understood, especially post-transcriptional and epigenetic regulation. And an unmet need remains for innovative treatment strategies for preventing, arresting, treating, and reversing diabetic kidney disease (DKD). People believe that protein methylation, including histone and non-histone, is an essential type of post-translational modification (PTM). However, prevalent reviews mainly focus on the causes such as DNA methylation. This review will take insights into the protein part. Furthermore, by emphasizing the close relationship between protein methylation and DKD, we will summarize the clinical research status and foresee the application prospect of protein methyltransferase (PMT) inhibitors in DKD treatment. In a nutshell, our review will contribute to a more profound understanding of DKD’s molecular mechanism and inspire people to dig into this field.
Collapse
Affiliation(s)
- Ye Cheng
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Yanna Chen
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Guodong Wang
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Pei Liu
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Guiling Xie
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Huan Jing
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Hongtao Chen
- Department of Anesthesiology, The Eighth People’s Hospital of Guangzhou, Guangzhou, China
| | - Youlin Fan
- Department of Anesthesiology, Guangzhou Panyu Central Hospital of Panyu District, Guangzhou, China
| | - Min Wang
- Department of Anesthesiology, The Gaoming People’s Hospital, Foshan, China
| | - Jun Zhou
- Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
- *Correspondence: Jun Zhou,
| |
Collapse
|
4
|
Xiang X, Zhu J, Dong G, Dong Z. Epigenetic Regulation in Kidney Transplantation. Front Immunol 2022; 13:861498. [PMID: 35464484 PMCID: PMC9024296 DOI: 10.3389/fimmu.2022.861498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/17/2022] [Indexed: 12/29/2022] Open
Abstract
Kidney transplantation is a standard care for end stage renal disease, but it is also associated with a complex pathogenesis including ischemia-reperfusion injury, inflammation, and development of fibrosis. Over the past decade, accumulating evidence has suggested a role of epigenetic regulation in kidney transplantation, involving DNA methylation, histone modification, and various kinds of non-coding RNAs. Here, we analyze these recent studies supporting the role of epigenetic regulation in different pathological processes of kidney transplantation, i.e., ischemia-reperfusion injury, acute rejection, and chronic graft pathologies including renal interstitial fibrosis. Further investigation of epigenetic alterations, their pathological roles and underlying mechanisms in kidney transplantation may lead to new strategies for the discovery of novel diagnostic biomarkers and therapeutic interventions.
Collapse
Affiliation(s)
- Xiaohong Xiang
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital of Central South University, Changsha, China.,Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood Veteran Affairs (VA) Medical Center, Augusta, GA, United States.,Department of Critical Care Medicine, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Jiefu Zhu
- Center of Nephrology and Dialysis, Transplantation, Renmin Hospital of Wuhan University, Wuhan, China
| | - Guie Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood Veteran Affairs (VA) Medical Center, Augusta, GA, United States
| | - Zheng Dong
- Department of Nephrology, Hunan Key Laboratory of Kidney Disease and Blood Purification, The Second Xiangya Hospital of Central South University, Changsha, China.,Department of Cellular Biology and Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood Veteran Affairs (VA) Medical Center, Augusta, GA, United States
| |
Collapse
|
5
|
Tanemoto F, Mimura I. Therapies Targeting Epigenetic Alterations in Acute Kidney Injury-to-Chronic Kidney Disease Transition. Pharmaceuticals (Basel) 2022; 15:ph15020123. [PMID: 35215236 PMCID: PMC8877070 DOI: 10.3390/ph15020123] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/15/2022] [Accepted: 01/18/2022] [Indexed: 12/04/2022] Open
Abstract
Acute kidney injury (AKI) was previously thought to be a merely transient event; however, recent epidemiological evidence supports the existence of a causal relationship between AKI episodes and subsequent progression to chronic kidney disease (CKD). Although the pathophysiology of this AKI-to-CKD transition is not fully understood, it is mediated by the interplay among multiple components of the kidney including tubular epithelial cells, endothelial cells, pericytes, inflammatory cells, and myofibroblasts. Epigenetic alterations including histone modification, DNA methylation, non-coding RNAs, and chromatin conformational changes, are also expected to be largely involved in the pathophysiology as a “memory” of the initial injury that can persist and predispose to chronic progression of fibrosis. Each epigenetic modification has a great potential as a therapeutic target of AKI-to-CKD transition; timely and target-specific epigenetic interventions to the various temporal stages of AKI-to-CKD transition will be the key to future therapeutic applications in clinical practice. This review elaborates on the latest knowledge of each mechanism and the currently available therapeutic agents that target epigenetic modification in the context of AKI-to-CKD transition. Further studies will elucidate more detailed mechanisms and novel therapeutic targets of AKI-to-CKD transition.
Collapse
|
6
|
Sánchez OF, Lin LF, Xie J, Freeman JL, Yuan C. Lead exposure induces dysregulation of constitutive heterochromatin hallmarks in live cells. Curr Res Toxicol 2021; 3:100061. [PMID: 35005634 PMCID: PMC8717252 DOI: 10.1016/j.crtox.2021.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/03/2021] [Accepted: 12/07/2021] [Indexed: 11/28/2022] Open
Abstract
Lead (Pb) is a heavy metal contaminant commonly found in air, soil, and drinking water due to legacy uses. Excretion of ingested Pb can result in extensive kidney damages due to elevated oxidative stress. Epigenetic alterations induced by exposure to Pb have also been implied but remain poorly understood. In this work, we assessed changes in repressive epigenetic marks, namely DNA methylation (meCpG) and histone 3 lysine 9 tri-methylation (H3K9me3) after exposure to Pb. Live cell epigenetic probes coupled to bimolecular fluorescence complementation (BiFC) were used to monitor changes in the selected epigenetic marks. Exposure to Pb significantly lowered meCpG and H3K9me3 levels in HEK293T cells suggesting global changes in constitutive heterochromatin. A heterodimeric pair of probes that tags chromatin regions enriched in both meCpG and H3K9me3 further confirmed our findings. The observed epigenetic changes can be partially attributed to aberrant transcriptional changes induced by Pb, such as overexpression of TET1 after Pb exposure. Lastly, we monitored changes in selected heterochromatin marks after removal of Pb and found that changes in these markers do not immediately recover to their original level suggesting potential long-term damages to chromatin structure.
Collapse
Affiliation(s)
- Oscar F. Sánchez
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Li F. Lin
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Junkai Xie
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Jennifer L. Freeman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA
- Purdue Center of Cancer Research, Purdue University, West Lafayette, IN 47907, USA
| | - Chongli Yuan
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA
- Purdue Center of Cancer Research, Purdue University, West Lafayette, IN 47907, USA
| |
Collapse
|
7
|
Rademaker MT, Pilbrow AP, Ellmers LJ, Palmer SC, Davidson T, Mbikou P, Scott NJA, Permina E, Charles CJ, Endre ZH, Richards AM. Acute Decompensated Heart Failure and the Kidney: Physiological, Histological and Transcriptomic Responses to Development and Recovery. J Am Heart Assoc 2021; 10:e021312. [PMID: 34533033 PMCID: PMC8649508 DOI: 10.1161/jaha.121.021312] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Acute decompensated heart failure (ADHF) is associated with deterioration in renal function-an important risk factor for poor outcomes. Whether ADHF results in permanent kidney damage/dysfunction is unknown. METHODS AND RESULTS We investigated for the first time the renal responses to the development of, and recovery from, ADHF using an ovine model. ADHF development induced pronounced hemodynamic changes, neurohormonal activation, and decline in renal function, including decreased urine, sodium and urea excretion, and creatinine clearance. Following ADHF recovery (25 days), creatinine clearance reductions persisted. Kidney biopsies taken during ADHF and following recovery showed widespread mesangial cell prominence, early mild acute tubular injury, and medullary/interstitial fibrosis. Renal transcriptomes identified altered expression of 270 genes following ADHF development and 631 genes following recovery. A total of 47 genes remained altered post-recovery. Pathway analysis suggested gene expression changes, driven by a network of inflammatory cytokines centered on IL-1β (interleukin 1β), lead to repression of reno-protective eNOS (endothelial nitric oxide synthase) signaling during ADHF development, and following recovery, activation of glomerulosclerosis and reno-protective pathways and repression of proinflammatory/fibrotic pathways. A total of 31 dysregulated genes encoding proteins detectable in urine, serum, and plasma identified potential candidate markers for kidney repair (including CNGA3 [cyclic nucleotide gated channel subunit alpha 3] and OIT3 [oncoprotein induced transcript 3]) or long-term renal impairment in ADHF (including ACTG2 [actin gamma 2, smooth muscle] and ANGPTL4 [angiopoietin like 4]). CONCLUSIONS In an ovine model, we provide the first direct evidence that an episode of ADHF leads to an immediate decline in kidney function that failed to fully resolve after ≈4 weeks and is associated with persistent functional/structural kidney injury. We identified molecular pathways underlying kidney injury and repair in ADHF and highlighted 31 novel candidate biomarkers for acute kidney injury in this setting.
Collapse
Affiliation(s)
- Miriam T Rademaker
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand
| | - Anna P Pilbrow
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand
| | - Leigh J Ellmers
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand
| | - Suetonia C Palmer
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand
| | - Trent Davidson
- Department of Anatomical Pathology Prince of Wales Hospital Sydney New South Wales Australia
| | - Prisca Mbikou
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand
| | - Nicola J A Scott
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand
| | - Elizabeth Permina
- Otago Genomics Facility Division of Health Sciences University of Otago Dunedin New Zealand
| | | | - Zoltán H Endre
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand.,Department of Nephrology Prince of Wales Hospital Sydney New South Wales Australia
| | - A Mark Richards
- Department of Medicine University of OtagoChristchurch Christchurch New Zealand.,Cardiovascular Research Institute National University of Singapore Singapore
| |
Collapse
|
8
|
Abstract
Epigenetics examines heritable changes in DNA and its associated proteins except mutations in gene sequence. Epigenetic regulation plays fundamental roles in kidney cell biology through the action of DNA methylation, chromatin modification via epigenetic regulators and non-coding RNA species. Kidney diseases, including acute kidney injury, chronic kidney disease, diabetic kidney disease and renal fibrosis are multistep processes associated with numerous molecular alterations even in individual kidney cells. Epigenetic alterations, including anomalous DNA methylation, aberrant histone alterations and changes of microRNA expression all contribute to kidney pathogenesis. These changes alter the genome-wide epigenetic signatures and disrupt essential pathways that protect renal cells from uncontrolled growth, apoptosis and development of other renal associated syndromes. Molecular changes impact cellular function within kidney cells and its microenvironment to drive and maintain disease phenotype. In this chapter, we briefly summarize epigenetic mechanisms in four kidney diseases including acute kidney injury, chronic kidney disease, diabetic kidney disease and renal fibrosis. We primarily focus on current knowledge about the genome-wide profiling of DNA methylation and histone modification, and epigenetic regulation on specific gene(s) in the pathophysiology of these diseases and the translational potential of identifying new biomarkers and treatment for prevention and therapy. Incorporating epigenomic testing into clinical research is essential to elucidate novel epigenetic biomarkers and develop precision medicine using emerging therapies.
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
Song T, Wang P, Li C, Jia L, Liang Q, Cao Y, Dong P, Shi H, Jiang M. Salidroside simultaneously reduces de novo lipogenesis and cholesterol biosynthesis to attenuate atherosclerosis in mice. Biomed Pharmacother 2021; 134:111137. [PMID: 33341055 DOI: 10.1016/j.biopha.2020.111137] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 12/07/2020] [Accepted: 12/10/2020] [Indexed: 12/12/2022] Open
Abstract
Salidroside is a kind of phenylethanoid glycoside and widespread in the plants from Rhodiola and Ligustrum species. Our previous study has reported that salidroside can prevent atherosclerosis progression by ameliorating glyerolipid and glycerophospholipid metabolism in apoE-deficient (apoE-/-) mice. However, its effect on neutral lipids and underlying mechanism remains largely unclear. Here we investigated the molecular mechanism of salidroside action from the perspective of metabolic regulation by integrating metabonomics and transcriptomics pattern. The results showed that salidroside significantly reduced cholesterols, esterified cholesterols, fatty acids, unsaturated fatty acids and triacylclycerols biosynthesis in liver through down-regulating the genes expressions of sterol regulatory element-binding proteins (Srebf1 and Srebf2). The expressions of SREBPs targeted and downstream genes, such as the encoding genes of fatty acid synthase (Fasn), glycerol-3-phosphate acyltransferase (Gpam), stearoyl-CoA desaturase (Scd), 3-hydroxy-3-methylglutaryl-CoA reductase (Hmgcr), and proprotein convertase subtilisin/kexin type 9 (Pcsk9), were also inhibited after salidroside administration. ATP citrate lyase gene (Acly) that encodes an important enzyme producing acetyl-CoA for cholesterol and fatty acid biosynthesis significantly decreased after treatment as well. Moreover, one of ketone body products, 3-hydroxybutyrate, was significantly up-regulated in drug-treated group, indicating that fatty acid degradation was accelerated by salidroside at the same time. Our findings identify salidroside as a regulator of lipid homeostasis in atherosclerotic mice, suggesting its potential to be an alternative medicine for lowering the risks of atherosclerosis-related diseases.
Collapse
Affiliation(s)
- Tongxin Song
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Pengli Wang
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Chenyang Li
- Department of Pharmacy, School of Medicine, Shenzhen University, Shenzhen 518060, China
| | - Li Jia
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Qianqian Liang
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Yuanlin Cao
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Pengzhi Dong
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Hong Shi
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Miaomiao Jiang
- State Key Laboratory of Component-based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China.
| |
Collapse
|
11
|
Martinez-Moreno JM, Fontecha-Barriuso M, Martín-Sánchez D, Sánchez-Niño MD, Ruiz-Ortega M, Sanz AB, Ortiz A. The Contribution of Histone Crotonylation to Tissue Health and Disease: Focus on Kidney Health. Front Pharmacol 2020; 11:393. [PMID: 32308622 PMCID: PMC7145939 DOI: 10.3389/fphar.2020.00393] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 03/16/2020] [Indexed: 12/12/2022] Open
Abstract
Acute kidney injury (AKI) and chronic kidney disease (CKD) are the most severe consequences of kidney injury. They are interconnected syndromes as CKD predisposes to AKI and AKI may accelerate CKD progression. Despite their growing impact on the global burden of disease, there is no satisfactory treatment for AKI and current therapeutic approaches to CKD remain suboptimal. Recent research has focused on the therapeutic target potential of epigenetic regulation of gene expression, including non-coding RNAs and the covalent modifications of histones and DNA. Indeed, several drugs targeting histone modifications are in clinical use or undergoing clinical trials. Acyl-lysine histone modifications (e.g. methylation, acetylation, and crotonylation) have modulated experimental kidney injury. Most recently, increased histone lysine crotonylation (Kcr) was observed during experimental AKI and could be reproduced in cultured tubular cells exposed to inflammatory stress triggered by the cytokine TWEAK. The degree of kidney histone crotonylation was modulated by crotonate availability and crotonate supplementation protected from nephrotoxic AKI. We now review the functional relevance of histone crotonylation in kidney disease and other pathophysiological contexts, as well as the implications for the development of novel therapeutic approaches. These studies provide insights into the overall role of histone crotonylation in health and disease.
Collapse
Affiliation(s)
- Julio M Martinez-Moreno
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain
| | - Miguel Fontecha-Barriuso
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain.,Red de Investigación Renal (REDinREN), Madrid, Spain
| | - Diego Martín-Sánchez
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain.,Red de Investigación Renal (REDinREN), Madrid, Spain
| | - Maria D Sánchez-Niño
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain.,Red de Investigación Renal (REDinREN), Madrid, Spain
| | - Marta Ruiz-Ortega
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain.,Red de Investigación Renal (REDinREN), Madrid, Spain.,School of Medicine, Autonomous University of Madrid (UAM), Madrid, Spain
| | - Ana B Sanz
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain.,Red de Investigación Renal (REDinREN), Madrid, Spain
| | - Alberto Ortiz
- Research Institute-Fundacion Jimenez Diaz, Autonomous University of Madrid (UAM), Madrid, Spain.,Red de Investigación Renal (REDinREN), Madrid, Spain.,School of Medicine, Autonomous University of Madrid (UAM), Madrid, Spain.,IRSIN, Madrid, Spain
| |
Collapse
|
12
|
Epigenetic regulation in AKI and kidney repair: mechanisms and therapeutic implications. Nat Rev Nephrol 2019; 15:220-239. [PMID: 30651611 DOI: 10.1038/s41581-018-0103-6] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Acute kidney injury (AKI) is a major public health concern associated with high morbidity and mortality. Despite decades of research, the pathogenesis of AKI remains incompletely understood and effective therapies are lacking. An increasing body of evidence suggests a role for epigenetic regulation in the process of AKI and kidney repair, involving remarkable changes in histone modifications, DNA methylation and the expression of various non-coding RNAs. For instance, increases in levels of histone acetylation seem to protect kidneys from AKI and promote kidney repair. AKI is also associated with changes in genome-wide and gene-specific DNA methylation; however, the role and regulation of DNA methylation in kidney injury and repair remains largely elusive. MicroRNAs have been studied quite extensively in AKI, and a plethora of specific microRNAs have been implicated in the pathogenesis of AKI. Emerging research suggests potential for microRNAs as novel diagnostic biomarkers of AKI. Further investigation into these epigenetic mechanisms will not only generate novel insights into the mechanisms of AKI and kidney repair but also might lead to new strategies for the diagnosis and therapy of this disease.
Collapse
|
13
|
Abdelzaher WY, Rofaeil RR, Ali DME, Attya ME. Protective effect of dipeptidyl peptidase-4 inhibitors in testicular torsion/detorsion in rats: a possible role of HIF-1α and nitric oxide. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2019; 393:603-614. [PMID: 31773182 DOI: 10.1007/s00210-019-01765-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 11/08/2019] [Indexed: 11/30/2022]
Abstract
Spermatic cord torsion is a serious and common urologic emergency. It requires early diagnosis for prevention of subfertility and testicular necrosis. Vildagliptin and sitagliptin are anti-diabetic drugs of the dipeptidyl peptidase-4 (DPP-4) inhibitors that have a protective role against cerebral ischemic stroke and cardiac ischemia reperfusion. This study aimed to investigate the role and mechanism of action of vildagliptin and sitagliptin in a model of testicular ischemia/reperfusion injury by testicular torsion/detorsion (T/D). Testicular T/D was done and vildagliptin and sitagliptin were administered either alone or in combination with nitric oxide synthase (NOS) inhibitor. Serum total cholesterol and testosterone were measured, while in testicular tissue testosterone, malondialdehyde (MDA) level, total antioxidant capacity (TAC), nitric oxide level, caspase-3, superoxide dismutase (SOD), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-α (TNF-α) and endothelial NOS (eNOS), and inducible NOS (iNOS) and neuronal NOS (nNOS) were measured. Histopathology of testicular tissue was done. Vildagliptin and sitagliptin increased serum testosterone, expression, and activity of SOD and testicular TAC. It also reduced total serum cholesterol, testicular MDA, caspase-3, HIF-1α, TNF-α, and expression of eNOS, iNOS, and nNOS. Vildagliptin and sitagliptin also improved histopathological picture of testicular tissue. NOS inhibitor produced similar result to DDP-4 inhibitors; however, its co-administration augmented the effect of vildagliptin and sitagliptin on these parameters. DPP-4 inhibitors, vildagliptin, and sitagliptin were protective against testicular T/D-induced injury mostly by anti-oxidative stress, and anti-apoptotic and anti-inflammatory actions that was augmented by NOS inhibition with a possible role for HIF-1α expression.
Collapse
Affiliation(s)
| | - Remon Roshdy Rofaeil
- Department of Pharmacology, Minia University, Minia, 61111, Egypt. .,Department of Pharmacology, Deraya University, New Minia City, Egypt.
| | | | | |
Collapse
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
Ferrè S, Igarashi P. New insights into the role of HNF-1β in kidney (patho)physiology. Pediatr Nephrol 2019; 34:1325-1335. [PMID: 29961928 PMCID: PMC6312759 DOI: 10.1007/s00467-018-3990-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/24/2018] [Accepted: 05/25/2018] [Indexed: 12/14/2022]
Abstract
Hepatocyte nuclear factor-1β (HNF-1β) is an essential transcription factor that regulates the development and function of epithelia in the kidney, liver, pancreas, and genitourinary tract. Humans who carry HNF1B mutations develop heterogeneous renal abnormalities, including multicystic dysplastic kidneys, glomerulocystic kidney disease, renal agenesis, renal hypoplasia, and renal interstitial fibrosis. In the embryonic kidney, HNF-1β is required for ureteric bud branching, initiation of nephrogenesis, and nephron segmentation. Ablation of mouse Hnf1b in nephron progenitors causes defective tubulogenesis, whereas later inactivation in elongating tubules leads to cyst formation due to downregulation of cystic disease genes, including Umod, Pkhd1, and Pkd2. In the adult kidney, HNF-1β controls the expression of genes required for intrarenal metabolism and solute transport by tubular epithelial cells. Tubular abnormalities observed in HNF-1β nephropathy include hyperuricemia with or without gout, hypokalemia, hypomagnesemia, and polyuria. Recent studies have identified novel post-transcriptional and post-translational regulatory mechanisms that control HNF-1β expression and activity, including the miRNA cluster miR17 ∼ 92 and the interacting proteins PCBD1 and zyxin. Further understanding of the molecular mechanisms upstream and downstream of HNF-1β may lead to the development of new therapeutic approaches in cystic kidney disease and other HNF1B-related renal diseases.
Collapse
Affiliation(s)
- Silvia Ferrè
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, Texas, USA,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Peter Igarashi
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA. .,Department of Medicine, University of Minnesota Medical School, 420 Delaware St. SE, MMC 194, Minneapolis, MN, 55455, USA.
| |
Collapse
|
16
|
Jia Y, Reddy MA, Das S, Oh HJ, Abdollahi M, Yuan H, Zhang E, Lanting L, Wang M, Natarajan R. Dysregulation of histone H3 lysine 27 trimethylation in transforming growth factor-β1-induced gene expression in mesangial cells and diabetic kidney. J Biol Chem 2019; 294:12695-12707. [PMID: 31266808 DOI: 10.1074/jbc.ra119.007575] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 06/13/2019] [Indexed: 12/20/2022] Open
Abstract
Transforming growth factor-β1 (TGF-β)-induced fibrotic and inflammatory genes in renal mesangial cells (MCs) play important roles in glomerular dysfunction associated with diabetic nephropathy (DN). TGF-β regulates gene expression in MCs by altering key chromatin histone modifications at target gene promoters. However, the role of the repressive histone H3 lysine 27 trimethylation (H3K27me3) modification is unclear. Here we show that TGF-β reduces H3K27me3 at the Ctgf, Serpine1, and Ccl2 gene promoters in rat MCs (RMCs) and reciprocally up-regulates the expression of these pro-fibrotic and inflammatory genes. In parallel, TGF-β down-regulates Enhancer of Zeste homolog 2 (Ezh2), an H3K27me3 methyltransferase, and decreases its recruitment at Ctgf and Ccl2 but not Serpine1 promoters. Ezh2 knockdown with siRNAs enhances TGF-β-induced expression of these genes, supporting its repressive function. Mechanistically, Ezh2 down-regulation is mediated by TGF-β-induced microRNA, miR-101b, which targets Ezh2 3'-UTR. TGF-β also up-regulates Jmjd3 and Utx in RMCs, suggesting a key role for these H3K27me3 demethylases in H3K27me3 inhibition. In RMCs, Utx knockdown inhibits hypertrophy, a key event in glomerular dysfunction. The H3K27me3 regulators are similarly altered in human and mouse MCs. High glucose inhibits Ezh2 and increases miR-101b in a TGF-β-dependent manner. Furthermore, in kidneys from rodent models of DN, fibrotic genes, miR-101b, and H3K27me3 demethylases are up-regulated, whereas Ezh2 protein levels as well as enrichment of Ezh2 and H3K27me3 at target genes are decreased, demonstrating in vivo relevance. These results suggest that H3K27me3 inhibition by TGF-β via dysregulation of related histone-modifying enzymes and miRNAs augments pathological genes mediating glomerular mesangial dysfunction and DN.
Collapse
Affiliation(s)
- Ye Jia
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010.,Division of Nephrology, First Hospital of Jilin University, Changchun 130021, China
| | - Marpadga A Reddy
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010
| | - Sadhan Das
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010
| | - Hyung Jung Oh
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010.,Ewha Institute of Convergence Medicine, Ewha Womans University Mokdong Hospital, Seoul 07985, South Korea
| | - Maryam Abdollahi
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010
| | - Hang Yuan
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010.,Division of Nephrology, First Hospital of Jilin University, Changchun 130021, China
| | - Erli Zhang
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010.,Department of Cardiology, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China
| | - Linda Lanting
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010
| | - Mei Wang
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010
| | - Rama Natarajan
- Department of Diabetes Complications and Metabolism, Beckman Research Institute of City of Hope, Duarte, California 91010
| |
Collapse
|
17
|
Gonsalez SR, Cortês AL, Silva RCD, Lowe J, Prieto MC, Silva Lara LD. Acute kidney injury overview: From basic findings to new prevention and therapy strategies. Pharmacol Ther 2019; 200:1-12. [PMID: 30959059 PMCID: PMC10134404 DOI: 10.1016/j.pharmthera.2019.04.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/27/2019] [Indexed: 01/24/2023]
Abstract
Acute kidney injury (AKI) is defined as a decrease in kidney function within hours, which encompasses both injury and impairment of renal function. AKI is not considered a pathological condition of single organ failure, but a syndrome in which the kidney plays an active role in the progression of multi-organ dysfunction. The incidence rate of AKI is increasing and becoming a common (8-16% of hospital admissions) and serious disease (four-fold increased hospital mortality) affecting public health costs worldwide. AKI also affects the young and previously healthy individuals affected by infectious diseases in Latin America. Because of the multifactorial pathophysiological mechanisms, there is no effective pharmacological therapy that prevents the evolution or reverses the injury once established; therefore, renal replacement therapy is the only current alternative available for renal patients. The awareness of an accurate and prompt recognition of AKI underlying the various clinical phenotypes is an urgent need for more effective therapeutic interventions to diminish mortality and socio-economic impacts of AKI. The use of biomarkers as an indicator of the initial stage of the disease is critical and the cornerstone to fulfill the gaps in the field. This review discusses emerging strategies from basic science toward the anticipation of features, treatment of AKI, and new treatments using pharmacological and stem cell therapies. We will also highlight bioartificial kidney studies, addressing the limitations of the development of this innovative technology.
Collapse
Affiliation(s)
- Sabrina Ribeiro Gonsalez
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho 373, Bloco J, sala 26, Rio de Janeiro, RJ 21941-902, Brazil
| | - Aline Leal Cortês
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho 373, Bloco J, sala 26, Rio de Janeiro, RJ 21941-902, Brazil
| | - Raquel Costa da Silva
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho 373, Bloco J, sala 26, Rio de Janeiro, RJ 21941-902, Brazil
| | - Jennifer Lowe
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho 373, sala I2-035, Rio de Janeiro, RJ 21941-902, Brazil
| | - Minolfa C Prieto
- Department of Physiology & Tulane Renal and Hypertension Center of Excellence, School of Medicine, Tulane University, New Orleans, LA 70112, USA
| | - Lucienne da Silva Lara
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho 373, Bloco J, sala 26, Rio de Janeiro, RJ 21941-902, Brazil.
| |
Collapse
|
18
|
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.
Collapse
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.
| |
Collapse
|
19
|
Mechanism mediating the protective effect of diacerein in ischemia-reperfusion-induced testicular injury in rats. Life Sci 2018; 209:57-62. [DOI: 10.1016/j.lfs.2018.07.060] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 07/28/2018] [Accepted: 07/31/2018] [Indexed: 01/14/2023]
|
20
|
Chakraborty A, Viswanathan P. Methylation-Demethylation Dynamics: Implications of Changes in Acute Kidney Injury. Anal Cell Pathol (Amst) 2018. [DOI: https://doi.org/10.1155/2018/8764384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Over the years, the epigenetic landscape has grown increasingly complex. Until recently, methylation of DNA and histones was considered one of the most important epigenetic modifications. However, with the discovery of enzymes involved in the demethylation process, several exciting prospects have emerged that focus on the dynamic regulation of methylation and its crucial role in development and disease. An interplay of the methylation-demethylation machinery controls the process of gene expression. Since acute kidney injury (AKI), a major risk factor for chronic kidney disease and death, is characterised by aberrant expression of genes, understanding the dynamics of methylation and demethylation will provide new insights into the intricacies of the disease. Research on epigenetics in AKI has only made its mark in the recent years but has provided compelling evidence that implicates the involvement of methylation and demethylation changes in its pathophysiology. In this review, we explore the role of methylation and demethylation machinery in cellular epigenetic control and further discuss the contribution of methylomic changes and histone modifications to the pathophysiology of AKI.
Collapse
Affiliation(s)
- Anubhav Chakraborty
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| | - Pragasam Viswanathan
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| |
Collapse
|
21
|
Solati Z, Edel AL, Shang Y, O K, Ravandi A. Oxidized phosphatidylcholines are produced in renal ischemia reperfusion injury. PLoS One 2018; 13:e0195172. [PMID: 29684044 PMCID: PMC5912739 DOI: 10.1371/journal.pone.0195172] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 03/16/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The aim of this study was to determine the individual oxidized phosphatidylcholine (OxPC) molecules generated during renal ischemia/ reperfusion (I/R) injury. METHODS Kidney ischemia was induced in male Sprague-Dawley rats by clamping the left renal pedicle for 45 min followed by reperfusion for either 6h or 24h. Kidney tissue was subjected to lipid extraction. Phospholipids and OxPC species were identified and quantitated using liquid chromatography coupled to electrospray ionization tandem mass spectrometry using internal standards. RESULT We identified fifty-five distinct OxPC in rat kidney following I/R injury. These included a variety of fragmented (aldehyde and carboxylic acid containing species) and non-fragmented products. 1-stearoyl-2-linoleoyl-phosphatidylcholine (SLPC-OH), which is a non-fragmented OxPC and 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PAzPC), which is a fragmented OxPC, were the most abundant OxPC species after 6h and 24 h I/R respectively. Total fragmented aldehyde OxPC were significantly higher in 6h and 24h I/R groups compared to sham operated groups (P = 0.03, 0.001 respectively). Moreover, levels of aldehyde OxPC at 24h I/R were significantly greater than those in 6h I/R (P = 0.007). Fragmented carboxylic acid increased significantly in 24h I/R group compared with sham and 6h I/R groups (P = 0.001, 0.001). Moreover, levels of fragmented OxPC were significantly correlated with creatinine levels (r = 0.885, P = 0.001). Among non-fragmented OxPC, only isoprostanes were elevated significantly in 6h I/R group compared with sham group but not in 24h I/R group (P = 0.01). No significant changes were observed in other non-fragmented OxPC including long chain products and terminal furans. CONCLUSION We have shown for the first time that bioactive OxPC species are produced in renal I/R and their levels increase with increasing time of reperfusion in a kidney model of I/R and correlate with severity of I/R injury. Given the pathological activity of fragmented OxPCs, therapies focused on their reduction may be a mechanism to attenuate renal I/R injury.
Collapse
Affiliation(s)
- Zahra Solati
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Andrea L. Edel
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Yue Shang
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Karmin O
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Amir Ravandi
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada
- * E-mail:
| |
Collapse
|
22
|
Chakraborty A, Viswanathan P. Methylation-Demethylation Dynamics: Implications of Changes in Acute Kidney Injury. Anal Cell Pathol (Amst) 2018; 2018:8764384. [PMID: 30073137 PMCID: PMC6057397 DOI: 10.1155/2018/8764384] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 06/05/2018] [Accepted: 06/14/2018] [Indexed: 02/05/2023] Open
Abstract
Over the years, the epigenetic landscape has grown increasingly complex. Until recently, methylation of DNA and histones was considered one of the most important epigenetic modifications. However, with the discovery of enzymes involved in the demethylation process, several exciting prospects have emerged that focus on the dynamic regulation of methylation and its crucial role in development and disease. An interplay of the methylation-demethylation machinery controls the process of gene expression. Since acute kidney injury (AKI), a major risk factor for chronic kidney disease and death, is characterised by aberrant expression of genes, understanding the dynamics of methylation and demethylation will provide new insights into the intricacies of the disease. Research on epigenetics in AKI has only made its mark in the recent years but has provided compelling evidence that implicates the involvement of methylation and demethylation changes in its pathophysiology. In this review, we explore the role of methylation and demethylation machinery in cellular epigenetic control and further discuss the contribution of methylomic changes and histone modifications to the pathophysiology of AKI.
Collapse
Affiliation(s)
- Anubhav Chakraborty
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| | - Pragasam Viswanathan
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| |
Collapse
|
23
|
Jouret F, Leenders J, Poma L, Defraigne JO, Krzesinski JM, de Tullio P. Nuclear Magnetic Resonance Metabolomic Profiling of Mouse Kidney, Urine and Serum Following Renal Ischemia/Reperfusion Injury. PLoS One 2016; 11:e0163021. [PMID: 27657885 PMCID: PMC5033333 DOI: 10.1371/journal.pone.0163021] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 09/01/2016] [Indexed: 12/29/2022] Open
Abstract
Background Ischemia/reperfusion (I/R) is the most common cause of acute kidney injury (AKI). Its pathophysiology remains unclear. Metabolomics is dedicated to identify metabolites involved in (patho)physiological changes of integrated living systems. Here, we performed 1H-Nuclear Magnetic Resonance metabolomics using urine, serum and kidney samples from a mouse model of renal I/R. Methods Renal 30-min ischemia was induced in 12-week-old C57BL/6J male mice by bilaterally clamping vascular pedicles, and was followed by 6, 24 or 48-hour reperfusion (n = 12/group). Sham-operated mice were used as controls. Statistical discriminant analyses, i.e. principal component analysis and orthogonal projections to latent structures (OPLS-DA), were performed on urine, serum and kidney lysates at each time-point. Multivariate receiver operating characteristic (ROC) curves were drawn, and sensitivity and specificity were calculated from ROC confusion matrix (with averaged class probabilities across 100 cross-validations). Results Urine OPLS-DA analysis showed a net separation between I/R and sham groups, with significant variations in levels of taurine, di- and tri-methylamine, creatine and lactate. Such changes were observed as early as 6 hours post reperfusion. Major metabolome modifications occurred at 24h post reperfusion. At this time-point, correlation coefficients between urine spectra and conventional AKI biomarkers, i.e. serum creatinine and urea levels, reached 0.94 and 0.95, respectively. The area under ROC curve at 6h, 24h and 48h post surgery were 0.73, 0.98 and 0.97, respectively. Similar discriminations were found in kidney samples, with changes in levels of lactate, fatty acids, choline and taurine. By contrast, serum OPLS-DA analysis could not discriminate sham-operated from I/R-exposed animals. Conclusions Our study demonstrates that renal I/R in mouse causes early and sustained metabolomic changes in urine and kidney composition. The most implicated pathways at 6h and 24h post reperfusion include gluconeogenesis, taurine and hypotaurine metabolism, whereas protein biosynthesis, glycolysis, and galactose and arginine metabolism are key at 48h post reperfusion.
Collapse
Affiliation(s)
- François Jouret
- Division of Nephrology, University of Liège Hospital (ULg CHU), Liège, Belgium
- Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA), Cardiovascular Sciences, University of Liège, Liège, Belgium
- * E-mail:
| | - Justine Leenders
- Centre for Interdisciplinary Research on Medicines (CIRM), University of Liège, Liège, Belgium
| | - Laurence Poma
- Division of Nephrology, University of Liège Hospital (ULg CHU), Liège, Belgium
- Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA), Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Jean-Olivier Defraigne
- Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA), Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Jean-Marie Krzesinski
- Division of Nephrology, University of Liège Hospital (ULg CHU), Liège, Belgium
- Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA), Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Pascal de Tullio
- Centre for Interdisciplinary Research on Medicines (CIRM), University of Liège, Liège, Belgium
| |
Collapse
|
24
|
Rao S, Walters KB, Wilson L, Chen B, Bolisetty S, Graves D, Barnes S, Agarwal A, Kabarowski JH. Early lipid changes in acute kidney injury using SWATH lipidomics coupled with MALDI tissue imaging. Am J Physiol Renal Physiol 2016; 310:F1136-47. [PMID: 26911846 DOI: 10.1152/ajprenal.00100.2016] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 02/23/2016] [Indexed: 11/22/2022] Open
Abstract
Acute kidney injury (AKI) is one of the leading causes of in-hospital morbidity and mortality, particularly in critically ill patients. Although our understanding of AKI at the molecular level remains limited due to its complex pathophysiology, recent advances in both quantitative and spatial mass spectrometric approaches offer new opportunities to assess the significance of renal metabolomic changes in AKI models. In this study, we evaluated lipid changes in early ischemia-reperfusion (IR)-related AKI in mice by using sequential window acquisition of all theoretical spectra (SWATH)-mass spectrometry (MS) lipidomics. We found a significant increase in two abundant ether-linked phospholipids following IR at 6 h postinjury, a plasmanyl choline, phosphatidylcholine (PC) O-38:1 (O-18:0, 20:1), and a plasmalogen, phosphatidylethanolamine (PE) O-42:3 (O-20:1, 22:2). Both of these lipids correlated with the severity of AKI as measured by plasma creatinine. In addition to many more renal lipid changes associated with more severe AKI, PC O-38:1 elevations were maintained at 24 h post-IR, while renal PE O-42:3 levels decreased, as were all ether PEs detected by SWATH-MS at this later time point. To further assess the significance of this early increase in PC O-38:1, we used matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) to determine that it occurred in proximal tubules, a region of the kidney that is most prone to IR injury and also rich in the rate-limiting enzymes involved in ether-linked phospholipid biosynthesis. Use of SWATH-MS lipidomics in conjunction with MALDI-IMS for lipid localization will help in elucidating the role of lipids in the pathobiology of AKI.
Collapse
Affiliation(s)
- Sangeetha Rao
- Division of Pediatric Critical Care, Children's Hospital of Alabama, Birmingham, Alabama
| | - Kelly B Walters
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama; Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Landon Wilson
- Targeted Metabolomics and Proteomics Laboratory, Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Bo Chen
- Division of Nephrology and Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Subhashini Bolisetty
- Division of Nephrology and Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - David Graves
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama
| | - Stephen Barnes
- Targeted Metabolomics and Proteomics Laboratory, Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Anupam Agarwal
- Division of Nephrology and Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Janusz H Kabarowski
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama;
| |
Collapse
|
25
|
Hu HJ, Luo XG, Dong QQ, Mu A, Shi GL, Wang QT, Chen XY, Zhou H, Zhang TC, Pan LW. Ethanol extract of Zhongtian hawthorn lowers serum cholesterol in mice by inhibiting transcription of 3-hydroxy-3-methylglutaryl-CoA reductase via nuclear factor-kappa B signal pathway. Exp Biol Med (Maywood) 2016; 241:667-74. [PMID: 26825354 DOI: 10.1177/1535370215627032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 12/15/2015] [Indexed: 12/26/2022] Open
Abstract
Hawthorn is a berry-like fruit from the species of Crataegus. In China, it has another more famous name, Shan-Zha, which has been used to improve digestion as a traditional Chinese medicine or food for thousands of years. Moreover, during the last decades, hawthorn has received more attention because of its potential to treat cardiovascular diseases. However, currently, only fruits of C. pinnatifida and C. pinnatifida var. major are included as Shan-Zha in the Chinese Pharmacopoeia. In this study, our results showed that the ethanol extract of Zhongtian hawthorn, a novel grafted cultivar of C. cuneata (wild Shan-Zha), could markedly reduce body weight and levels of serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, and liver cholesterol of hyperlipidemia mice. It could suppress the stimulation effect of high-fat diet on the transcription of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and p65, and counteract the downregulation of CYP7A1 and LDLR. In addition, the results of luciferase reporter assay and Western blot showed that the transcriptional activity of HMGCR promoter was inhibited by Zhongtian hawthorn ethanol extract in a dose-dependent manner, while overexpression of p65 could reverse this transcriptional repression effect. These results suggested that Zhongtian hawthorn could provide health benefits by counteracting the high-fat diet-induced hypercholesteolemic and hyperlipidemic effects in vivo, and the mechanism underlying this event was mainly dependent on the suppressive effect of Zhongtian hawthorn ethanol extract on the transcription of HMGCR via nuclear factor-kappa B (NF-κB) signal pathway. Therefore, this novel cultivar of hawthorn cultivar which has much bigger fruits, early bearing, high yield, cold resistance, and drought resistance, might be considered as a good alternative to Shan-Zha and has great value in the food and medicine industry. In addition, to our best knowledge, this is also the first report that the extract of Crataegus could suppress the transcription of HMGCR via NF-κB signal pathway.
Collapse
Affiliation(s)
- Hai-Jie Hu
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Xue-Gang Luo
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Qing-Qing Dong
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Ai Mu
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Guo-Long Shi
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Qiu-Tong Wang
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Xiao-Ying Chen
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Hao Zhou
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Tong-Cun Zhang
- Key Lab of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, P. R. China Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, P. R. China
| | - Li-Wen Pan
- Hezhou University, Hezhou 542800, P. R. China
| |
Collapse
|
26
|
Aboudehen K, Kim MS, Mitsche M, Garland K, Anderson N, Noureddine L, Pontoglio M, Patel V, Xie Y, DeBose-Boyd R, Igarashi P. Transcription Factor Hepatocyte Nuclear Factor-1β Regulates Renal Cholesterol Metabolism. J Am Soc Nephrol 2015; 27:2408-21. [PMID: 26712526 DOI: 10.1681/asn.2015060607] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 11/11/2015] [Indexed: 12/16/2022] Open
Abstract
HNF-1β is a tissue-specific transcription factor that is expressed in the kidney and other epithelial organs. Humans with mutations in HNF-1β develop kidney cysts, and HNF-1β regulates the transcription of several cystic disease genes. However, the complete spectrum of HNF-1β-regulated genes and pathways is not known. Here, using chromatin immunoprecipitation/next generation sequencing and gene expression profiling, we identified 1545 protein-coding genes that are directly regulated by HNF-1β in murine kidney epithelial cells. Pathway analysis predicted that HNF-1β regulates cholesterol metabolism. Expression of dominant negative mutant HNF-1β or kidney-specific inactivation of HNF-1β decreased the expression of genes that are essential for cholesterol synthesis, including sterol regulatory element binding factor 2 (Srebf2) and 3-hydroxy-3-methylglutaryl-CoA reductase (Hmgcr). HNF-1β mutant cells also expressed lower levels of cholesterol biosynthetic intermediates and had a lower rate of cholesterol synthesis than control cells. Additionally, depletion of cholesterol in the culture medium mitigated the inhibitory effects of mutant HNF-1β on the proteins encoded by Srebf2 and Hmgcr, and HNF-1β directly controlled the renal epithelial expression of proprotein convertase subtilisin-like kexin type 9, a key regulator of cholesterol uptake. These findings reveal a novel role of HNF-1β in a transcriptional network that regulates intrarenal cholesterol metabolism.
Collapse
Affiliation(s)
- Karam Aboudehen
- Departments of Internal Medicine, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota; and
| | | | | | | | | | | | - Marco Pontoglio
- Department of Development, Reproduction and Cancer, National Institute of Health and Medical Research (INSERM) U1016, The National Center for Scientific Research (CNRS) Joint Research Unit (UMR) 8104, University of Paris Descartes, Institut Cochin, Paris, France
| | | | | | - Russell DeBose-Boyd
- Molecular Genetics, and Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Peter Igarashi
- Departments of Internal Medicine, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota; and Pediatrics and
| |
Collapse
|
27
|
Rodríguez-Romo R, Berman N, Gómez A, Bobadilla NA. Epigenetic regulation in the acute kidney injury to chronic kidney disease transition. Nephrology (Carlton) 2015; 20:736-743. [DOI: 10.1111/nep.12521] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2015] [Indexed: 02/06/2023]
Affiliation(s)
- Roxana Rodríguez-Romo
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| | - Nathan Berman
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| | - Arturo Gómez
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| | - Norma A Bobadilla
- Molecular Physiology Unit; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
- Department of Nephrology; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Mexico City Mexico
| |
Collapse
|
28
|
Recent developments in epigenetics of acute and chronic kidney diseases. Kidney Int 2015; 88:250-61. [PMID: 25993323 PMCID: PMC4522401 DOI: 10.1038/ki.2015.148] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/22/2015] [Accepted: 03/30/2015] [Indexed: 12/25/2022]
Abstract
The growing epidemic of obesity and diabetes, the aging population as well as prevalence of drug abuse has led to significant increases in the rates of the closely associated acute and chronic kidney diseases, including diabetic nephropathy. Furthermore, evidence shows that parental behavior and diet can affect the phenotype of subsequent generations via epigenetic transmission mechanisms. These data suggest a strong influence of the environment on disease susceptibility and that, apart from genetic susceptibility, epigenetic mechanisms need to be evaluated to gain critical new information about kidney diseases. Epigenetics is the study of processes that control gene expression and phenotype without alterations in the underlying DNA sequence. Epigenetic modifications, including cytosine DNA methylation and covalent post translational modifications of histones in chromatin are part of the epigenome, the interface between the stable genome and the variable environment. This dynamic epigenetic layer responds to external environmental cues to influence the expression of genes associated with disease states. The field of epigenetics has seen remarkable growth in the past few years with significant advances in basic biology, contributions to human disease, as well as epigenomics technologies. Further understanding of how the renal cell epigenome is altered by metabolic and other stimuli can yield novel new insights into the pathogenesis of kidney diseases. In this review, we have discussed the current knowledge on the role of epigenetic mechanisms (primarily DNA me and histone modifications) in acute and chronic kidney diseases, and their translational potential to identify much needed new therapies.
Collapse
|
29
|
Abstract
Acute kidney injury (AKI) is a risk factor for chronic kidney disease and death. Despite progress made in understanding the cellular and molecular basis of AKI pathogenesis there has been no improvement in the high mortality rate from this disease in decades. Epigenetics is one of the most intensively studied fields of biology today and represents a new paradigm for understanding the pathophysiology of disease. Although epigenetics of AKI is a nascent field, the available information already is providing compelling evidence that chromatin biology plays a critical role in this disease. In this article we explore what is known about the contribution of epigenetic mechanisms to the pathophysiology of AKI and how this knowledge already is guiding the development of new diagnostic tools and epigenetic therapies.
Collapse
|
30
|
SREBP-1 has a prognostic role and contributes to invasion and metastasis in human hepatocellular carcinoma. Int J Mol Sci 2014; 15:7124-38. [PMID: 24776759 PMCID: PMC4057663 DOI: 10.3390/ijms15057124] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 03/16/2014] [Accepted: 04/10/2014] [Indexed: 01/18/2023] Open
Abstract
Sterol regulatory element-binding protein 1 (SREBP-1) is a well-known nuclear transcription factor involved in lipid synthesis. Recent studies have focused on its functions in tumor cell proliferation and apoptosis, but its role in cell migration and invasion, especially in hepatocellular carcinoma (HCC), is still unclear. In this study, we found that the expression of SREBP-1 in HCC tissues was significantly higher than those in matched tumor-adjacent tissues (p < 0.05). SREBP-1 was expressed at significantly higher levels in patients with large tumor size, high histological grade and advanced tumor-node-metastasis (TNM) stage (p < 0.05). The positive expression of SREBP-1 correlated with a worse 3-year overall and disease-free survival of HCC patients (p < 0.05). Additionally, SREBP-1 was an independent factor for predicting both 3-year overall and disease-free survival of HCC patients (p < 0.05). In vitro studies revealed that downregulation of SREBP-1 inhibited cell proliferation and induced apoptosis in both HepG2 and MHCC97L cells (p < 0.05). Furthermore, wound healing and transwell assays showed that SREBP-1 knockdown prominently inhibited cell migration and invasion in both HepG2 and MHCC97L cells (p < 0.05). These results suggest that SREBP-1 may serve as a prognostic marker in HCC and may promote tumor progression by promoting cell growth and metastasis.
Collapse
|
31
|
Losartan reverses permissive epigenetic changes in renal glomeruli of diabetic db/db mice. Kidney Int 2013; 85:362-73. [PMID: 24088954 PMCID: PMC3946617 DOI: 10.1038/ki.2013.387] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 08/05/2013] [Accepted: 08/08/2013] [Indexed: 02/07/2023]
Abstract
Epigenetic mechanisms such as chromatin histone H3 lysine methylation and acetylation have been implicated in diabetic vascular complications. However, histone modification profiles at pathologic genes associated with diabetic nephropathy in vivo and their regulation by the angiotensin II type 1 receptor (AT1R) are not clear. Here we tested whether treatment of type 2 diabetic db/db mice with the AT1R blocker Losartan not only ameliorates diabetic nephropathy, but also reverses epigenetic changes. As expected, the db/db mice had increased blood pressure, mesangial hypertrophy, proteinuria and glomerular expression of RAGE and PAI-1 versus control db/+ mice. This was associated with increased RNA Polymerase II recruitment and permissive histone marks as well as decreased repressive histone marks at these genes, and altered expression of relevant histone modification enzymes. Increased MCP-1 mRNA levels were not associated with such epigenetic changes, suggesting post-transcriptional regulation. Losartan attenuated key parameters of diabetic nephropathy and gene expression, and reversed some but not all the epigenetic changes in db/db mice. Losartan also attenuated increased H3K9/14Ac at RAGE, PAI-1 and MCP-1 promoters in mesangial cells cultured under diabetic conditions. Our results provide novel information about the chromatin state at key pathologic genes in vivo in diabetic nephropathy mediated in part by AT1R. Thus combination therapies targeting epigenetic regulators and AT1R could be evaluated for more effective treatment of diabetic nephropathy.
Collapse
|
32
|
Zager RA. 'Biologic memory' in response to acute kidney injury: cytoresistance, toll-like receptor hyper-responsiveness and the onset of progressive renal disease. Nephrol Dial Transplant 2013; 28:1985-93. [PMID: 23761460 PMCID: PMC3765022 DOI: 10.1093/ndt/gft101] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 03/29/2013] [Indexed: 11/14/2022] Open
Abstract
Following the induction of ischemic or toxin-mediated acute kidney injury (AKI), cellular adaptations occur that 're-program' how the kidney responds to future superimposed insults. This re-programming is not simply a short-lived phenomenon; rather it can persist for many weeks, implying that a state of 'biologic memory' has emerged. These changes can be both adaptive and maladaptive in nature and they can co-exist in time. A beneficial adaptation is the emergence of acquired cytoresistance, whereby a number of physiologic responses develop that serve to protect the kidney against further ischemic or nephrotoxic attack. Conversely, some changes are maladaptive, such as a predisposition to Gram-negative or Gram-positive bacteremia due to a renal tubular up-regulation of toll-like receptor responses. This latter change culminates in exaggerated cytokine production, and with efflux into the systemic circulation, extra-renal tissue injury can result (so-called 'organ cross talk'). Another maladaptive response is a persistent up-regulation of pro-inflammatory, pro-fibrotic and vasoconstrictive genes, culminating in progressive renal injury and ultimately end-stage renal failure. The mechanisms by which this biologic re-programming, or biologic memory, is imparted remain subjects for considerable debate. However, injury-induced, and stable, epigenetic remodeling at pro-inflammatory/pro-fibrotic genes seems likely to be involved. The goal of this editorial is to highlight that the so-called 'maintenance phase' of acute renal failure is not a static one, somewhere between injury induction and the onset of repair. Rather, this period is one in which the induction of 'biologic memory' can ultimately impact renal functional recovery, extra-renal injury and the possible transition of AKI into chronic, progressive renal disease.
Collapse
Affiliation(s)
- Richard A. Zager
- The Fred Hutchinson Cancer Research Center, and the University of Washington, Seattle, WA, USA
| |
Collapse
|
33
|
Zager RA, Johnson ACM, Andress D, Becker K. Progressive endothelin-1 gene activation initiates chronic/end-stage renal disease following experimental ischemic/reperfusion injury. Kidney Int 2013; 84:703-12. [PMID: 23698233 PMCID: PMC3788861 DOI: 10.1038/ki.2013.157] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 02/25/2013] [Accepted: 03/01/2013] [Indexed: 02/06/2023]
Abstract
This study assessed whether endothelin-1 (ET-1) helps mediate postischemic acute kidney injury (AKI) progression to chronic kidney disease (CKD). The impact(s) of potent ETA or ETB receptor-specific antagonists (Atrasentan and BQ-788, respectively) on disease progression were assessed 24 h or 2 weeks following 30 min of unilateral ischemia in CD-1 mice. Unilateral ischemia caused progressive renal ET-1 protein/mRNA increases with concomitant ETA, but not ETB, mRNA elevations. Extensive histone remodeling consistent with gene activation and increased RNA polymerase II (Pol II) binding occurred at the ET-1 gene. Unilateral ischemia produced progressive renal injury as indicated by severe histologic injury and a 40% loss of renal mass. Pre- and post-ischemia or just postischemic treatment with Atrasentan conferred dramatic protective effects such as decreased tubule/microvascular injury, normalized tissue lactate, and total preservation of renal mass. Nuclear KI-67 staining was not increased by Atrasentan, implying that increased tubule proliferation was not involved. Conversely, ETB blockade had no protective effect. Thus, our findings provide the first evidence that ET-1 operating through ETA can have a critical role in ischemic AKI progression to CKD. Blockade of ETA provided dramatic protection, indicating the functional significance of these results.
Collapse
Affiliation(s)
- Richard A Zager
- 1] The Department of Medicine, University of Washington, Seattle, Washington, USA [2] Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | | | | |
Collapse
|
34
|
Komers R, Mar D, Denisenko O, Xu B, Oyama TT, Bomsztyk K. Epigenetic changes in renal genes dysregulated in mouse and rat models of type 1 diabetes. J Transl Med 2013; 93:543-52. [PMID: 23508046 DOI: 10.1038/labinvest.2013.47] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Epigenetic processes are increasingly being recognized as factors in the pathophysiology of diabetes complications, but few chromatin studies have been done in diabetic nephropathy (DN). We hypothesized that changes in mRNA expression of DN-related genes are associated with epigenetic alterations and aberrant expression of histone-modifying enzymes. RT-PCR and a matrix-chromatin immunoprecipitation platform were used to examine renal mRNA expression, RNA polymerase II (Pol II) recruitment, and epigenetic marks at DN-related genes in the mouse (OVE26) and streptozotocin-induced rat models of type 1 diabetes. Diabetes induced renal expression of Cox2, S100A4/FSP-1, and vimentin genes in both the mouse and the rat models of DN. Mcp-1 and laminin γ1 (Lamc1) expression were increased in diabetic mice but not in rats. Comparison of mRNA and Pol II levels suggested that the diabetes-induced expression of these transcripts is mediated by transcriptional and posttranscriptional processes. Decreases in histone H3 lysine 27 tri-methylation (H3K27m3, silencing mark) and increases in H3 lysine 4 di-methylation (H3K4m2, activating mark) levels were the most consistent epigenetic alterations in the tested genes. In agreement with these results, immunoblot analysis showed increased protein abundance of renal H3K27m2/3 demethylase KDM6A, but no changes in cognate methyltransferase Ezh2 in kidneys of the OVE26 mice compared with controls. In diabetic rats, Ezh2 expression was higher without changes in KDM6A, demonstrating that mechanisms of DN-induced H3K27m3 loss could be species specific. In summary, we show that altered mRNA expression of some DN-related genes is associated with changes in Pol II recruitment and a corresponding decrease in repressive H3K27m3 at the selected loci, and at least in mice with equivalent changes in renal expression of cognate histone-modifying enzymes. This pattern could contribute to diabetes-mediated transitions in chromatin that facilitate transcriptional changes in the diabetic kidney.
Collapse
Affiliation(s)
- Radko Komers
- Division of Nephrology and Hypertension, Oregon Health and Science University, Portland, OR, USA
| | | | | | | | | | | |
Collapse
|
35
|
Heyman SN, Evans RG, Rosen S, Rosenberger C. Cellular adaptive changes in AKI: mitigating renal hypoxic injury. Nephrol Dial Transplant 2012; 27:1721-8. [DOI: 10.1093/ndt/gfs100] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
36
|
Zager RA, Johnson ACM, Becker K. Plasma and urinary heme oxygenase-1 in AKI. J Am Soc Nephrol 2012; 23:1048-57. [PMID: 22440905 DOI: 10.1681/asn.2011121147] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
AKI induces upregulation of heme oxygenase 1 (HO-1), which exerts cytoprotective effects and modulates the renal response to injury, suggesting that a biomarker of intrarenal HO-1 activity may be useful. Because HO-1 largely localizes to the endoplasmic reticulum and has no known secretory pathway, it is unclear whether plasma or urinary levels of HO-1 reflect intrarenal HO-1 expression. We measured plasma and urinary levels of HO-1 by ELISA during the induction and/or maintenance phases of four mouse models of AKI: ischemia/reperfusion, glycerol-induced rhabdomyolysis, cisplatin nephrotoxicity, and bilateral ureteral obstruction. In addition, we measured levels of HO-1 mRNA and protein in the renal cortex. Each AKI model increased renal HO-1 gene expression, which corresponded with release of HO-1 into plasma and urine by 4 hours. Over time, the magnitudes of plasma and urinary HO-1 paralleled renal cortical gene expression. AKI and the associated uremia did not seem to affect extrarenal HO-1 gene activity assessed in the liver, lung, and spleen. In iron-challenged, cultured proximal tubule cells, we observed a positive correlation between HO-1 mRNA level and HO-1 release. In humans, 10 patients with AKI demonstrated markedly higher levels of plasma and urine HO-1 levels than 10 critically ill patients without AKI or 20 patients with CKD or ESRD. In summary, these data suggest that plasma and urinary HO-1 levels may serve as biomarkers of AKI and intrarenal HO-1 gene activity.
Collapse
Affiliation(s)
- Richard A Zager
- Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N., Seattle, WA 98109, USA.
| | | | | |
Collapse
|
37
|
Zhao HL, Sui Y, He L, Guan J, Xiao SJ, Zhong DR, Xu Q, Zeng SE. Lipid partitioning after uninephrectomy. Acta Diabetol 2011; 48:317-328. [PMID: 21528432 DOI: 10.1007/s00592-011-0286-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 04/13/2011] [Indexed: 11/28/2022]
Abstract
This longitudinal study addressed the sequential events and metabolic consequences of lipid partitioning following uninephrectomy. Adult male Sprague-Dawley rats were randomized into sham operation (n = 15) or left uninephrectomy (UNX, n = 18). At 1 and 3 months post nephrectomy, three rats from each group were killed for histopathological examination of adipocyte differentiation and lipid accumulation. Renal protein expression of the lipogenic peroxisome proliferator-activated receptor-γ (PPAR-γ), HMG-CoA reductase (HMGCR), and adiponectin receptor was detected by Western blot and immunofluorescence microscopy. Blood lipids, glucose, insulin, and renal functions were longitudinally measured up to 10 months after operation. The UNX rats progressively developed lipodystrophy of subcutaneous and visceral adipose depots with failure of adipocyte differentiation and lipid storage, followed by blood lipid elevation and ectopic lipid deposition with cellular lipid peroxidation, and renal adipogenesis with chronic inflammatory infiltration. Despite having standard diet, normal food consumption and normal body weight, the uninephrectomized rats with defective lipid partitioning manifested a myriad of homeostatic disturbances including insulin resistance, hyperglycemia, adiponectin resistance, and upregulation of PPAR-γ and HMGCR. Abnormal lipid partitioning from adipose depots to circulation and non-adipose tissues and non-adipocytic cells contributes to homeostatic disturbances and lipogenic activation.
Collapse
Affiliation(s)
- Hai-Lu Zhao
- Faculty of Basic Medicine, Guilin Medical University, North 2nd Huan Cheng Road, 541004, Guilin, China.
| | - Yi Sui
- Department of Medicine and Therapeutics, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China
| | - Lan He
- Department of Medicine and Therapeutics, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China
| | - Jing Guan
- Department of Medicine and Therapeutics, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China
| | - Sheng-Jun Xiao
- Faculty of Basic Medicine, Guilin Medical University, North 2nd Huan Cheng Road, 541004, Guilin, China
| | - Ding-Rong Zhong
- Department of Pathology, Peking Union Medical College Hospital, 100730, Beijing, China
| | - Qing Xu
- Faculty of Basic Medicine, Guilin Medical University, North 2nd Huan Cheng Road, 541004, Guilin, China
| | - Si-En Zeng
- Faculty of Basic Medicine, Guilin Medical University, North 2nd Huan Cheng Road, 541004, Guilin, China
| |
Collapse
|
38
|
Zager RA, Johnson ACM, Becker K. Acute unilateral ischemic renal injury induces progressive renal inflammation, lipid accumulation, histone modification, and "end-stage" kidney disease. Am J Physiol Renal Physiol 2011; 301:F1334-45. [PMID: 21921025 PMCID: PMC3233867 DOI: 10.1152/ajprenal.00431.2011] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 09/08/2011] [Indexed: 01/04/2023] Open
Abstract
There is an emerging concept in clinical nephrology that acute kidney injury (AKI) can initiate chronic kidney disease (CKD). However, potential mechanisms by which this may occur remain elusive. Hence, this study tested the hypotheses that 1) AKI triggers progressive activation of selected proinflammatory genes, 2) there is a relative failure of compensatory anti-inflammatory gene expression, 3) proinflammatory lipid accumulation occurs, 4) these changes correspond with "gene-activating" histone acetylation, and 5) in concert, progressive renal disease results. CD-1 mice were subjected to 30 min of unilateral renal ischemia. Assessments were made 1 day, 1 wk, or 3 wk later. Results were contrasted to those observed in uninjured contralateral kidneys or in kidneys from normal mice. Progressive renal injury occurred throughout the 3-wk postischemic period, as denoted by stepwise increases in neutrophil gelatinase-associated lipocalin gene induction and ongoing histologic damage. By 3 wk postischemia, progressive renal disease was observed (massive tubular dropout; 2/3rds reduction in renal weight). These changes corresponded with progressive increases in proinflammatory cytokine/chemokine gene expression (MCP-1, TNF-α, TGF-β1), a relative failure of anti-inflammatory enzyme/cytokine (heme oxygenase-1; IL-10) upregulation, and progressive renal lipid (cholesterol/triglyceride) loading. Stepwise increases in collagen III mRNA and collagen deposition (Sirius red staining) indicated a progressive profibrotic response. Postischemic dexamethasone treatment significantly preserved renal mass, indicating functional significance of the observed proinflammatory state. Progressive gene-activating H3 acetylation was observed by ELISA, rising from 5% at baseline to 75% at 3 wk. This was confirmed by chromatin immunoprecipitation assay of target genes. In sum, these results provide experimental support for the clinical concept that AKI can trigger CKD, this is partially mediated by progressive postischemic inflammation, ongoing lipid accumulation results (potentially evoking "lipotoxicity"), and increasing histone acetylation at proinflammatory/profibrotic genes may contribute to this self-sustaining injury-promoting state.
Collapse
Affiliation(s)
- Richard A Zager
- Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N., Seattle, WA 98109, USA.
| | | | | |
Collapse
|
39
|
Johnson AC, Ware LB, Himmelfarb J, Zager RA. HMG-CoA reductase activation and urinary pellet cholesterol elevations in acute kidney injury. Clin J Am Soc Nephrol 2011; 6:2108-13. [PMID: 21799150 DOI: 10.2215/cjn.02440311] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND OBJECTIVES Experimental acute kidney injury (AKI) activates the HMG-CoA reductase (HMGCR) gene, producing proximal tubule cholesterol loading. AKI also causes sloughing of proximal tubular cell debris into tubular lumina. This study tested whether these two processes culminate in increased urinary pellet cholesterol content, and whether the latter has potential AKI biomarker utility. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Urine samples were collected from 29 critically ill patients with (n = 14) or without (n= 15) AKI, 15 patients with chronic kidney disease, and 15 healthy volunteers. Centrifuged urinary pellets underwent lipid extraction, and the extracts were assayed for cholesterol content (factored by membrane phospholipid phosphate content). In vivo HMGCR activation was sought by measuring levels of RNA polymerase II (Pol II), and of a gene activating histone mark (H3K4m3) at exon 1 of the HMGCR gene (chromatin immunoprecipitation assay of urine chromatin samples). RESULTS AKI+ patients had an approximate doubling of urinary pellet cholesterol content compared with control urine samples (versus normal; P < 0.001). The values significantly correlated (r, 0.5; P < 0.01) with serum, but not urine, creatinine concentrations. Conversely, neither critical illness without AKI nor chronic kidney disease raised pellet cholesterol levels. Increased HMGCR activity in the AKI+ patients was supported by three- to fourfold increased levels of Pol II, and of H3K4m3, at the HMGCR gene (versus controls or AKI- patients). CONCLUSIONS (1) Clinical AKI, like experimental AKI, induces HMGCR gene activation; (2) increased urinary pellet cholesterol levels result; and (3) urine pellet cholesterol levels may have potential AKI biomarker utility. The latter will require future testing in a large prospective trial.
Collapse
Affiliation(s)
- Ali Cm Johnson
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | | | | |
Collapse
|
40
|
Gokey NG, Lopez-Anido C, Gillian-Daniel AL, Svaren J. Early growth response 1 (Egr1) regulates cholesterol biosynthetic gene expression. J Biol Chem 2011; 286:29501-10. [PMID: 21712389 DOI: 10.1074/jbc.m111.263509] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The early growth response (EGR) family of transcription factors has been implicated in control of lipid biosynthetic genes. Egr1 is induced by insulin both in vitro and in vivo and is the most highly expressed family member in liver. In this study, we investigated whether Egr1 regulates cholesterol biosynthetic genes in liver. Using an insulin-sensitive liver cell line, we show that localization of Egr1 to cholesterol biosynthetic genes is induced by insulin treatment and that this localization precedes the induction of the genes. Reduction in Egr1 expression using targeted siRNA blunted the insulin-dependent induction of cholesterol genes. A similar reduction in squalene epoxidase expression was also observed in Egr1 null mice. In addition, application of chromatin immunoprecipitation (ChIP) samples to tiled gene microarrays revealed localization of Egr1 in promoter regions of many cholesterol gene loci. In vivo ChIP assays using liver tissue show that Egr1 localization to several cholesterol biosynthetic gene promoters is induced by feeding. Finally, analysis of plasma cholesterol in Egr1(-/-) mice indicated a significant decrease in serum cholesterol when compared with wild-type mice. Together these data point to Egr1 as a modulator of the cholesterol biosynthetic gene family in liver.
Collapse
Affiliation(s)
- Nolan G Gokey
- Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin 53705, USA
| | | | | | | |
Collapse
|
41
|
Sonawane PJ, Sahu BS, Sasi BK, Geedi P, Lenka G, Mahapatra NR. Functional promoter polymorphisms govern differential expression of HMG-CoA reductase gene in mouse models of essential hypertension. PLoS One 2011; 6:e16661. [PMID: 21304971 PMCID: PMC3031630 DOI: 10.1371/journal.pone.0016661] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 01/10/2011] [Indexed: 11/18/2022] Open
Abstract
3-Hydroxy-3-methylglutaryl-coenzyme A [HMG-CoA] reductase gene (Hmgcr) is a susceptibility gene for essential hypertension. Sequencing of the Hmgcr locus in genetically hypertensive BPH (blood pressure high), genetically hypotensive BPL (blood pressure low) and genetically normotensive BPN (blood pressure normal) mice yielded a number of single nucleotide polymorphisms (SNPs). BPH/BPL/BPN Hmgcr promoter-luciferase reporter constructs were generated and transfected into liver HepG2, ovarian CHO, kidney HEK-293 and neuronal N2A cells for functional characterization of the promoter SNPs. The BPH-Hmgcr promoter showed significantly less activity than the BPL-Hmgcr promoter under basal as well as nicotine/cholesterol-treated conditions. This finding was consistent with lower endogenous Hmgcr expression in liver and lower plasma cholesterol in BPH mice. Transfection experiments using 5′-promoter deletion constructs (strategically made to assess the functional significance of each promoter SNP) and computational analysis predicted lower binding affinities of transcription factors c-Fos, n-Myc and Max with the BPH-promoter as compared to the BPL-promoter. Corroboratively, the BPH promoter-luciferase reporter construct co-transfected with expression plasmids of these transcription factors displayed less pronounced augmentation of luciferase activity than the BPL construct, particularly at lower amounts of transcription factor plasmids. Electrophoretic mobility shift assays also showed diminished interactions of the BPH promoter with HepG2 nuclear proteins. Taken together, this study provides mechanistic basis for the differential Hmgcr expression in these mouse models of human essential hypertension and have implications for better understanding the role of this gene in regulation of blood pressure.
Collapse
Affiliation(s)
- Parshuram J. Sonawane
- Cardiovascular Genetics Laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, India
| | - Bhavani S. Sahu
- Cardiovascular Genetics Laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, India
| | - Binu K. Sasi
- Cardiovascular Genetics Laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, India
| | - Parimala Geedi
- Cardiovascular Genetics Laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, India
| | - Govinda Lenka
- Cardiovascular Genetics Laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, India
| | - Nitish R. Mahapatra
- Cardiovascular Genetics Laboratory, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, India
- * E-mail:
| |
Collapse
|
42
|
Zager RA, Johnson ACM. Progressive histone alterations and proinflammatory gene activation: consequences of heme protein/iron-mediated proximal tubule injury. Am J Physiol Renal Physiol 2009; 298:F827-37. [PMID: 20032114 DOI: 10.1152/ajprenal.00683.2009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Rhabdomyolysis (Fe)-induced acute renal failure (ARF) causes renal inflammation, and, with repetitive insults, progressive renal failure can result. To gain insights into these phenomena, we assessed the impact of a single episode of glycerol-induced rhabdomyolysis on proinflammatory/profibrotic [TNF-alpha, monocyte chemoattractant protein-1 (MCP-1), and transforming growth factor-beta1 (TGF-beta1)] gene expression and the time course of these changes. CD-1 mice were studied 1-7 days after glycerol injection. Normal mice served as controls. RNA polymerase II (Pol II) binding to the TNF-alpha, MCP-1, and TGF-beta1 genes, "gene-activating" histone modifications [histone 3 lysine 4 (H3K4) trimethylation (H3K4m3) and histone 2 variant H2A.Z], and cognate mRNA levels were assessed. Results were contrasted to changes in anti-inflammatory heme oxygenase-1 (HO-1). Glycerol produced severe ARF (blood urea nitrogen approximately 150-180 mg/dl) followed by marked improvement by day 7 (blood urea nitrogen approximately 40 mg/dl). Early increases in TNF-alpha, MCP-1, and TGF-beta1 mRNAs, Pol II gene binding, and H3K4m3/H2A.Z levels were observed. These progressed with time, despite resolution of azotemia. Comparable early HO-1 changes were observed. However, HO-1 mRNA normalized by day 7, and progressive Pol II binding/histone alterations did not occur. Fe-mediated injury to cultured proximal tubule (HK-2) cells recapitulated these in vivo results. Hence, this in vitro model was used for mechanistic assessments. On the basis of these studies, it was determined that 1) the H3K4m3/H2A.Z increases are early events (i.e., they precede mRNA increases), 2) subsequent mRNA elevations reflect transcription, not mRNA stabilization (actinomycin D assessments), and 3) increased transcription, per se, helps sustain elevated H2A.Z levels. We conclude that 1) Fe/glycerol-induced tubular injury causes sustained proinflammatory gene activation, 2) decreasing HO-1 expression, as reflected by mRNA levels, may facilitate this proinflammatory state, and 3) gene-activating histone modifications are early injury events and progressively increase at selected proinflammatory genes. Thus they may help sustain a proinflammatory state, despite resolving ARF.
Collapse
Affiliation(s)
- Richard A Zager
- Fred Hutchinson Cancer Research Center and Department of Medicine, University of Washington, Seattle, Washington 98109, USA.
| | | |
Collapse
|
43
|
Tissot van Patot MC, Murray AJ, Beckey V, Cindrova-Davies T, Johns J, Zwerdlinger L, Jauniaux E, Burton GJ, Serkova NJ. Human placental metabolic adaptation to chronic hypoxia, high altitude: hypoxic preconditioning. Am J Physiol Regul Integr Comp Physiol 2009; 298:R166-72. [PMID: 19864339 PMCID: PMC2806207 DOI: 10.1152/ajpregu.00383.2009] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have previously demonstrated placentas from laboring deliveries at high altitude have lower binding of hypoxia-inducible transcription factor (HIF) to DNA than those from low altitude. It has recently been reported that labor causes oxidative stress in placentas, likely due to ischemic hypoxic insult. We hypothesized that placentas of high-altitude residents acquired resistance, in the course of their development, to oxidative stress during labor. Full-thickness placental tissue biopsies were collected from laboring vaginal and nonlaboring cesarean-section term (37–41 wk) deliveries from healthy pregnancies at sea level and at 3,100 m. After freezing in liquid nitrogen within 5 min of delivery, we quantified hydrophilic and lipid metabolites using 31P and 1H NMR metabolomics. Metabolic markers of oxidative stress, increased glycolysis, and free amino acids were present in placentas following labor at sea level, but not at 3,100 m. In contrast, at 3,100 m, the placentas were characterized by the presence of concentrations of stored energy potential (phosphocreatine), antioxidants, and low free amino acid concentrations. Placentas from pregnancies at sea level subjected to labor display evidence of oxidative stress. However, laboring placentas at 3,100 m have little or no oxidative stress at the time of delivery, suggesting greater resistance to ischemia-reperfusion. We postulate that hypoxic preconditioning might occur in placentas that develop at high altitude.
Collapse
Affiliation(s)
- Martha C Tissot van Patot
- Department of Anesthesiology, University of Colorado Denver Health Sciences Center, Aurora, Colorado, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Zager RA, Johnson ACM, Lund S. Uremia impacts renal inflammatory cytokine gene expression in the setting of experimental acute kidney injury. Am J Physiol Renal Physiol 2009; 297:F961-70. [PMID: 19656911 DOI: 10.1152/ajprenal.00381.2009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Inflammatory cytokines are evoked by acute kidney injury (AKI) and may contribute to evolving renal disease. However, the impact of AKI-induced uremia on proinflammatory (e.g., TNF-alpha, MCP-1, TGF-beta1) and anti-inflammatory (e.g., IL-10) cytokine gene expression remains unknown. This study was undertaken to gain some initial insights into this issue. CD-1 mice were subjected to left renal ischemia-reperfusion (I/R) in the absence or presence of uremia (+/- right ureteral transection). TNF-alpha, MCP-1, TGF-beta1, and IL-10 mRNAs, cytokine protein levels, and RNA polymerase II (Pol II) recruitment to these genes were assessed. Renal cytokine mRNA levels were also contrasted with unilateral vs. bilateral renal parenchymal damage (I/R or ureteral obstruction). Potential effects of uremia on cytokine mRNAs in the absence of parenchymal renal damage [bilateral ureteral transection (BUTx)] were sought. Finally, the impact of simulated in vitro uremia (HK-2 tubular cells exposed to peritoneal dialysate from uremic vs. normal mice) on cytokine mRNA and microRNA profiles was assessed. Uremia blunted TNF-alpha, MCP-1, and TGF-beta1 mRNA increases in all three in vivo parenchymal acute renal failure models. These results were paralleled by reductions in cytokine protein levels and Pol II recruitment to their respective genes. Conversely, uremia increased IL-10 mRNA, both in the presence and absence (BUTx) of parenchymal renal damage. The uremic milieu also suppressed HK-2 cell proinflammatory cytokine mRNA levels and altered the expression of least 69 microRNAs (P < 0.0001). We conclude that both pro- and anti-inflammatory cytokine gene expressions are influenced by uremia, with a potential predilection toward an anti-inflammatory state. Changes in gene transcription (as reflected by Pol II recruitment), and possible posttranscriptional modifications (known to be induced by microRNAs), are likely involved.
Collapse
Affiliation(s)
- Richard A Zager
- Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N, Rm. D2-190, Seattle, WA 98109, USA.
| | | | | |
Collapse
|
45
|
Naito M, Zager RA, Bomsztyk K. BRG1 increases transcription of proinflammatory genes in renal ischemia. J Am Soc Nephrol 2009; 20:1787-96. [PMID: 19556365 DOI: 10.1681/asn.2009010118] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Acute kidney injury stimulates renal production of inflammatory mediators, including TNF-alpha and monocyte chemoattractant protein 1 (MCP-1). These responses reflect, in part, injury-induced transcription of proinflammatory genes by proximal tubule cells. Because of the compact structure of chromatin, a series of events at specified loci remodel chromatin to provide access for transcription factors and RNA polymerase II (Pol II). Here, we examined the role of Brahma-related gene-1 (BRG1), a chromatin remodeling enzyme, in the transcription of TNF-alpha and MCP-1 in response to renal ischemia. Two hours after renal ischemic injury in mice, renal TNF-alpha and MCP-1 mRNA increased and remained elevated for at least 1 wk. Matrix chromatin immunoprecipitation assays revealed sustained increases in Pol II at these genes, suggesting that the elevated mRNA levels were, at least in part, transcriptionally mediated. The profile of BGR1 binding to the genes encoding TNF-alpha and MCP-1 resembled Pol II recruitment. Knockdown of BRG1 by small interfering RNA blocked an ATP depletion-induced increase in TNF-alpha and MCP-1 transcription in a human proximal tubule cell line; this effect was associated with decreased recruitment of BRG1 and Pol II to these genes. In conclusion, BRG1 promotes increased transcription of TNF-alpha and MCP-1 by the proximal tubule in response to renal ischemia.
Collapse
Affiliation(s)
- Masayo Naito
- Department of Medicine, University of Washington, Seattle, WA 98109, USA
| | | | | |
Collapse
|
46
|
Journal Club. Kidney Int 2009. [DOI: 10.1038/ki.2009.56] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
47
|
Zager RA, Johnson ACM. Renal ischemia-reperfusion injury upregulates histone-modifying enzyme systems and alters histone expression at proinflammatory/profibrotic genes. Am J Physiol Renal Physiol 2009; 296:F1032-41. [PMID: 19261745 DOI: 10.1152/ajprenal.00061.2009] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Ischemic renal injury can produce chronic renal inflammation and fibrosis. This study tested whether ischemia-reperfusion (I/R) activates histone-modifying enzyme systems and alters histone expression at selected proinflammatory/profibrotic genes. CD-1 mice were subjected to 30 min of unilateral I/R. Contralateral kidneys served as controls. At 1, 3, or 7 days of reflow, bilateral nephrectomy was performed. Renal cortices were probed for monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-beta1 (TGF-beta1), and collagen III mRNAs and cytokine levels. RNA polymerase II (Pol II) binding, which initiates transcription, was quantified at exon 1 of the MCP-1, TGF-beta1, collagen III genes (chromatin immunoprecipitation assay). Two representative gene-activating histone modifications [histone 3 lysine 4 (H3K4) trimethylation (m3) (H3K4m3); histone 2 variant H2A.Z] were sought. Degrees of binding of two relevant histone-modifying enzymes (Set1, BRG1) to target genes were assessed. Renal cortical Set1, BRG1, and H2A.Z mRNAs were measured. Finally, the potential utility of urinary mRNA concentrations as noninvasive markers of these in vivo processes was tested. I/R caused progressive increases in Pol II binding to MCP-1, TGF-beta1, and collagen III genes. Parallel increases in cognate mRNAs also were expressed. Progressive increases in renal cortical Set1, BRG1, H2A.Z mRNAs, and increased Set1/BRG1 binding to target genes occurred. These changes corresponded with: 1) progressive elevations of H3K4m3 and H2A.Z at each test gene; 2) increases in renal cortical TGF-beta1/MCP-1 cytokines; and 3) renal collagen deposition (assessed by histomorphology). Postischemic increases in urinary TGF-beta1, MCP-1, Set1, and BRG1 mRNAs were also observed. We conclude that: 1) I/R upregulates histone-modifying enzyme systems, 2) histone modifications at proinflammatory/profibrotic genes can result, and 3) urinary mRNA assessments may have utility for noninvasive monitoring of these in vivo events.
Collapse
Affiliation(s)
- Richard A Zager
- Department of Medicine, University of Washington, and the Clinical Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, WA 98109, USA.
| | | |
Collapse
|
48
|
Zager RA. Uremia induces proximal tubular cytoresistance and heme oxygenase-1 expression in the absence of acute kidney injury. Am J Physiol Renal Physiol 2008; 296:F362-8. [PMID: 19036845 DOI: 10.1152/ajprenal.90645.2008] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Acute kidney injury (AKI) induces adaptive responses within proximal tubular (PT) cells that serve to protect them from further ischemic or toxic damage. However, it is not known whether uremia, a potential consequence of AKI, independently alters susceptibility to tubular injury. To address this issue, we subjected CD-1 mice to bilateral ureteral transection (BUTx), which produces uremia (blood urea nitrogen approximately 150 mg/dl) in the absence of direct renal damage. PT segments were then isolated from BUTx and control mice and subjected to in vitro hypoxic injury. Additionally, "in vitro uremia" was modeled in isolated tubules or in cultured PT (HK-2) cells by addition of 1) peritoneal dialysate (obtained from mice with bilateral ureteral obstruction), 2) peritoneal fluid (from BUTx mice), or 3) normal human urine (pH 7.4, with and without boiling). Effects on injury severity (lactate dehydrogenase release) were assessed. Finally, because uremia is a prooxidant state, it was hypothesized that BUTx would increase renal lipid peroxidation (malondialdehyde) and induce heme oxygenase-1 (HO-1), a redox-sensitive cytoprotective protein. BUTx conferred striking protection against hypoxic damage. This could be partially modeled in tubules and HK-2 cells by induction of in vitro uremia. Urine's protective action was heat labile (largely destroyed by boiling). BUTx caused a tripling of renal malondialdehyde and HO-1 protein levels. Increased HO-1 transcription was likely involved, as indicated by a tripling of HO-1 mRNA and RNA polymerase II binding along the HO-1 gene (chromatin immunoprecipitation assay). "Gene-activating" histone modifications [H3K4 trimethylation (H3K4m3) and histone 2 variant (H2A.Z)] at HO-1 gene loci were also observed. Uremia, per se, can contribute to the AKI-induced cytoresistance. Low-molecular-weight, heat-labile, cytoprotective factor(s) and uremia-induced renal stress responses (e.g., HO-1 gene activation) are likely involved. Finally, renal HO-1 induction following AKI may reflect direct cell injury effects and adaptations to uremia.
Collapse
Affiliation(s)
- Richard A Zager
- Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N, Rm. D2-190, Seattle, WA 98109, USA.
| |
Collapse
|