51
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Inagi R. Organelle Stress and Metabolic Derangement in Kidney Disease. Int J Mol Sci 2022; 23:1723. [PMID: 35163648 PMCID: PMC8836232 DOI: 10.3390/ijms23031723] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/29/2022] [Accepted: 01/30/2022] [Indexed: 02/01/2023] Open
Abstract
Advanced multiomics analysis has revealed novel pathophysiological mechanisms in kidney disease. In particular, proteomic and metabolomic analysis shed light on mitochondrial dysfunction (mitochondrial stress) by glycation in diabetic or age-related kidney disease. Further, metabolic damage often results from organelle stress, such as mitochondrial stress and endoplasmic reticulum (ER) stress, as well as interorganelle communication, or "organelle crosstalk", in various kidney cells. These contribute to progression of the disease phenotype. Aberrant tubular mitochondrial lipid metabolism leads to tubular inflammation and fibrosis. This review article summarizes updated evidence regarding organelle stress, organelle crosstalk, and metabolic derangement in kidney disease.
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Affiliation(s)
- Reiko Inagi
- Division of Chronic Kidney Disease (CKD) Pathophysiology, The University of Tokyo Graduate School of Medicine, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-8655, Japan
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52
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Luan ZL, Zhang C, Ming WH, Huang YZ, Guan YF, Zhang XY. Nuclear receptors in renal health and disease. EBioMedicine 2022; 76:103855. [PMID: 35123268 PMCID: PMC8819107 DOI: 10.1016/j.ebiom.2022.103855] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/31/2021] [Accepted: 01/18/2022] [Indexed: 02/07/2023] Open
Abstract
As a major social and economic burden for the healthcare system, kidney diseases contribute to the constant increase of worldwide deaths. A deeper understanding of the underlying mechanisms governing the etiology, development and progression of kidney diseases may help to identify potential therapeutic targets. As a superfamily of ligand-dependent transcription factors, nuclear receptors (NRs) are critical for the maintenance of normal renal function and their dysfunction is associated with a variety of kidney diseases. Increasing evidence suggests that ligands for NRs protect patients from renal ischemia/reperfusion (I/R) injury, drug-induced acute kidney injury (AKI), diabetic nephropathy (DN), renal fibrosis and kidney cancers. In the past decade, some breakthroughs have been made for the translation of NR ligands into clinical use. This review summarizes the current understanding of several important NRs in renal physiology and pathophysiology and discusses recent findings and applications of NR ligands in the management of kidney diseases.
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Affiliation(s)
- Zhi-Lin Luan
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian 116044, China; Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China; Dalian Key Laboratory for Nuclear Receptors in Major Metabolic Diseases, Dalian, Liaoning 116044, China
| | - Cong Zhang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian 116044, China
| | - Wen-Hua Ming
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian 116044, China
| | - Ying-Zhi Huang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian 116044, China
| | - You-Fei Guan
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian 116044, China; Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Dalian Medical University, Dalian 116044, China; Dalian Key Laboratory for Nuclear Receptors in Major Metabolic Diseases, Dalian, Liaoning 116044, China.
| | - Xiao-Yan Zhang
- Health Science Center, East China Normal University, Shanghai 200241, China.
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The Therapeutic Potential of Zinc-Alpha2-Glycoprotein (AZGP1) in Fibrotic Kidney Disease. Int J Mol Sci 2022; 23:ijms23020646. [PMID: 35054830 PMCID: PMC8775758 DOI: 10.3390/ijms23020646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 11/30/2022] Open
Abstract
Chronic kidney disease (CKD) is characterized by a long-term loss of kidney function and, in most cases, by progressive fibrosis. Zinc-alpha2-glycoprotein (AZGP1) is a secreted protein, which is expressed in many different tissues and has been associated with a variety of functions. In a previous study, we have shown in cell culture and in AZGP1 deficient mice that AZGP1 has protective anti-fibrotic effects. In the present study, we tested the therapeutic potential of an experimental increase in AZGP1 using two different strategies. (1) C57Bl/6J mice were treated systemically with recombinant AZGP1, and (2) a transgenic mouse strain was generated to overexpress AZGP1 conditionally in proximal tubular cells. Mice underwent unilateral uretic obstruction as a pro-fibrotic kidney stress model, and kidneys were examined after 14 days. Recombinant AZGP1 treatment was accompanied by better preservation of tubular integrity, reduced collagen deposition, and lower expression of injury and fibrosis markers. Weaker but similar tendencies were observed in transgenic AZGP1 overexpressing mice. Higher AZGP1 levels led to a significant reduction in stress-induced accumulation of tubular lipid droplets, which was paralleled by improved expression of key players in lipid metabolism and fatty acid oxidation. Together these data show beneficial effects of elevated AZGP1 levels in fibrotic kidney disease and highlight a novel link to tubular cell lipid metabolism, which might open up new opportunities for CKD treatment.
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54
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Feng L, Chen T, Wang X, Xiong C, Chen J, Wu S, Ning J, Zou H. Metabolism Score for Visceral Fat (METS-VF): A New Predictive Surrogate for CKD Risk. Diabetes Metab Syndr Obes 2022; 15:2249-2258. [PMID: 35936056 PMCID: PMC9346409 DOI: 10.2147/dmso.s370222] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 07/13/2022] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Metabolic disorders are closely related to the occurrence and development of chronic kidney disease (CKD). We explored the prospective association between the Metabolic Score for Visceral Fat (METS-VF) and CKD in a 5-year follow-up study. PATIENTS AND METHODS In this cohort study, 631 adults not suffering from CKD from Wanzhai Town, in China in 2012 were included at baseline and followed up in 2017 and 2018. Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between METS-VF and CKD risk. Area under the receiver operating characteristic curve (AUC) analyses were used to evaluate the ability of METS-VF, waist-to-height ratio (WhtR), visceral adiposity index (VAI), homeostatic model assessment of insulin resistance (HOMA-IR), body mass index (BMI) to predict CKD risk. RESULTS We identified 103 CKD cases during follow-up. After adjustment for confounding factors, comparing the lowest quartile of METS-VF, the OR (95% CI) of CKD risk in the highest quartile was 3.04 (1.39-6.64). The per Standard deviation (SD) increase in METS-VF was positively correlated with CKD risk. The AUC of METS-VF for predicting CKD risk was, in general, higher than that for WhtR, VAI, HOMA-IR, and BMI. CONCLUSION METS-VF may be an indicator for predicting CKD risk.
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Affiliation(s)
- Ling Feng
- Department of Nephrology, The Third Affiliated Hospital, Southern Medical University, Guangzhou, People’s Republic of China
- Department of Nephrology, Shenzhen Hospital, Southern Medical University, Shenzhen, People’s Republic of China
| | - Tong Chen
- Department of Nephrology, South China Hospital of Shenzhen University, Shenzhen, People’s Republic of China
| | - Xuan Wang
- Department of Nephrology, The Third Affiliated Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Chongxiang Xiong
- Department of Nephrology, The Third Affiliated Hospital, Southern Medical University, Guangzhou, People’s Republic of China
- Department of Nephrology, The First Dongguan Affiliated Hospital of Guangdong Medical University, Dongguan, People’s Republic of China
| | - Jianhui Chen
- Department of Nephrology, The Third Affiliated Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Shiquan Wu
- Department of Nephrology, South China Hospital of Shenzhen University, Shenzhen, People’s Republic of China
| | - Jing Ning
- Department of Nephrology, South China Hospital of Shenzhen University, Shenzhen, People’s Republic of China
| | - Hequn Zou
- Department of Nephrology, The Third Affiliated Hospital, Southern Medical University, Guangzhou, People’s Republic of China
- Department of Nephrology, South China Hospital of Shenzhen University, Shenzhen, People’s Republic of China
- Correspondence: Hequn Zou, Department of Nephrology, The Third Affiliated Hospital, Southern Medical University, 183, Zhongshan West Avenue, Tianhe District, Guangzhou, 510630, People’s Republic of China, Email
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55
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Thongnak L, Pengrattanachot N, Promsan S, Phengpol N, Sutthasupha P, Chatsudthipong V, Lungkaphin A. The combination of dapagliflozin and statins ameliorates renal injury through attenuating the activation of inflammasome-mediated autophagy in insulin-resistant rats. J Biochem Mol Toxicol 2021; 36:e22978. [PMID: 34939712 DOI: 10.1002/jbt.22978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 11/25/2021] [Accepted: 12/09/2021] [Indexed: 11/07/2022]
Abstract
Long-term use of a high-fat diet with high-fructose (HFF) intake could promote insulin resistance and induce lipid accumulation leading to kidney injury possibly via impairment of the autophagy process and enhancement of the inflammasome pathway. We investigated whether dapagliflozin as a monotherapy or combined with atorvastatin could restore kidney autophagy impairment and reduce inflammasome activation associated with kidney injury induced by HFF consumption. Male Wistar rats were given an HFF for 16 weeks and then treated with dapagliflozin with or without atorvastatin for 4 weeks. Impaired glucose tolerance, dyslipidemia, renal lipid accumulation along with impaired renal autophagy and activated inflammasome pathway promoted renal injury were exhibited in HFF rats. Dapagliflozin with or without atorvastatin treatment could partially restore disrupted metabolic parameters and reduce kidney injury. In particular, the combination treatment group showed significant amelioration of inflammasome activation and autophagy impairment. In conclusion, the combination therapy of dapagliflozin and atorvastatin has a positive effect on renal injury associated with autophagy and inflammasome activation induced by HFF in insulin-resistant rats. This study is the first report demonstrating the underlying mechanism associated with a combination treatment of dapagliflozin and atorvastatin on autophagy and inflammasome pathways in an insulin-resistant condition. Therefore, dapagliflozin in combination with atorvastatin may be a further preventive or therapeutic strategy for chronic kidney disease in an insulin-resistant or diabetic condition.
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Affiliation(s)
- Laongdao Thongnak
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | - Sasivimon Promsan
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Nichakorn Phengpol
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Prempree Sutthasupha
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Varanuj Chatsudthipong
- Research Center of Transport Protein for Medical Innovation, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Anusorn Lungkaphin
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Functional Food Research Center for Well-Being, Chiang Mai University, Chiang Mai, Thailand
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56
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Zhu X, Jiang L, Long M, Wei X, Hou Y, Du Y. Metabolic Reprogramming and Renal Fibrosis. Front Med (Lausanne) 2021; 8:746920. [PMID: 34859009 PMCID: PMC8630632 DOI: 10.3389/fmed.2021.746920] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 10/20/2021] [Indexed: 12/24/2022] Open
Abstract
There are several causes of chronic kidney disease, but all of these patients have renal fibrosis. Although many studies have examined the pathogenesis of renal fibrosis, there are still no effective treatments. A healthy and balanced metabolism is necessary for normal cell growth, proliferation, and function, but metabolic abnormalities can lead to pathological changes. Normal energy metabolism is particularly important for maintaining the structure and function of the kidneys because they consume large amounts of energy. We describe the metabolic reprogramming that occurs during renal fibrosis, which includes changes in fatty acid metabolism and glucose metabolism, and the relationship of these changes with renal fibrosis. We also describe the potential role of novel drugs that disrupt this metabolic reprogramming and the development of fibrosis, and current and future challenges in the treatment of fibrosis.
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Affiliation(s)
- Xiaoyu Zhu
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
| | - Lili Jiang
- Physical Examination Center, The First Hospital of Jilin University, Changchun, China
| | - Mengtuan Long
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
| | - Xuejiao Wei
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
| | - Yue Hou
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
| | - Yujun Du
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
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57
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Castro BBA, Foresto-Neto O, Saraiva-Camara NO, Sanders-Pinheiro H. Renal lipotoxicity: Insights from experimental models. Clin Exp Pharmacol Physiol 2021; 48:1579-1588. [PMID: 34314523 DOI: 10.1111/1440-1681.13556] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 07/13/2021] [Accepted: 07/23/2021] [Indexed: 11/29/2022]
Abstract
In recent decades, there has been a progressive increase in the prevalence of obesity and chronic kidney disease. Renal lipotoxicity has been associated with obesity. Although lipids play fundamental physiological roles, the accumulation of lipids in kidney cells may cause dysfunction and/or renal fibrosis. Adipose tissue that exceeds their lipid storage capacity begins to release triglycerides into the bloodstream that can get stored in several organs, including the kidneys. The mechanisms underlying renal lipotoxicity involve intracellular lipid accumulation and organelle dysfunction, which trigger oxidative stress and inflammation that consequently result in insulin resistance and albuminuria. However, the specific pathways involved in renal lipotoxicity have not yet been fully understood. We aimed to summarize the current knowledge on the mechanisms by which lipotoxicity affects the renal morphology and function in experimental models of obesity. The accumulation of fatty acids in tubular cells has been described as the main mechanism of lipotoxicity; however, lipids and their metabolism also affect the function and the survival of podocytes. In this review, we presented indication of mitochondrial, lysosomal and endoplasmic reticulum alterations involved in kidney damage caused by obesity. The kidney is vulnerable to lipotoxicity, and studies of the mechanisms underlying renal injury caused by obesity can help identify therapeutic targets to control renal dysfunction.
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Affiliation(s)
- Barbara Bruna Abreu Castro
- Laboratory of Experimental Nephrology, Nucleus of Animal Experimentation (NIDEAL), Centre of Reproductive Biology (CBR), Federal University of Juiz de Fora (UFJF, Juiz de Fora, Minas Gerais, Brazil
- Nephrology Division and Interdisciplinary Nucleus of Studies and Research in Nephrology (NIEPEN), Federal University of Juiz de Fora (UFJF, Juiz de Fora, Minas Gerais, Brazil
| | - Orestes Foresto-Neto
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo (USP, São Paulo, São Paulo, Brazil
| | - Niels Olsen Saraiva-Camara
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo (USP, São Paulo, São Paulo, Brazil
| | - Helady Sanders-Pinheiro
- Laboratory of Experimental Nephrology, Nucleus of Animal Experimentation (NIDEAL), Centre of Reproductive Biology (CBR), Federal University of Juiz de Fora (UFJF, Juiz de Fora, Minas Gerais, Brazil
- Nephrology Division and Interdisciplinary Nucleus of Studies and Research in Nephrology (NIEPEN), Federal University of Juiz de Fora (UFJF, Juiz de Fora, Minas Gerais, Brazil
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58
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Yoshioka K, Hirakawa Y, Kurano M, Ube Y, Ono Y, Kojima K, Iwama T, Kano K, Hasegawa S, Inoue T, Shimada T, Aoki J, Yatomi Y, Nangaku M, Inagi R. Lysophosphatidylcholine mediates fast decline in kidney function in diabetic kidney disease. Kidney Int 2021; 101:510-526. [PMID: 34856312 DOI: 10.1016/j.kint.2021.10.039] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 10/15/2021] [Accepted: 10/26/2021] [Indexed: 12/30/2022]
Abstract
Some patients with diabetic kidney disease (DKD) show a fast progression of kidney dysfunction and are known as a "fast decliner" (FD). Therefore, it is critical to understand pathomechanisms specific for fast decline. Here, we performed a comprehensive metabolomic analysis of patients with stage G3 DKD and identified increased urinary lysophosphatidylcholine (LPC) in fast decline. This was confirmed by quantification of urinary LPC using mass spectrometry and identified urinary LPC containing saturated fatty acids palmitic (16:0) and stearic (18:0) acids was increased in FDs. The upsurge in urinary LPC levels was correlated with a decline in estimated glomerular filtration rate after 2.5 years. To clarify a pathogenic role of LPC in FD, we studied an accelerated rat model of DKD and observed an increase in LPC (16:0) and (18:0) levels in the urine and kidney tubulointerstitium as the disease progressed. These findings suggested that local dysregulation of lipid metabolism resulted in excessive accumulation of this LPC species in the kidney. Our in vitro studies also confirmed LPC-mediated lipotoxicity in cultured proximal tubular cells. LPC induced accumulation of lipid droplets via activation of peroxisome proliferator-activated receptor-δ followed by upregulation of the lipid droplet membrane protein perilipin 2 and decreased autophagic flux, thereby inducing organelle stress and subsequent apoptosis. Thus, LPC (16:0) and (18:0) may mediate a fast progression of DKD and may serve as a target for novel therapeutic approaches.
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Affiliation(s)
- Kentaro Yoshioka
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan; Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan; R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | - Yosuke Hirakawa
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Makoto Kurano
- Department of Clinical Laboratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yuko Ube
- R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | - Yoko Ono
- R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | | | - Taiga Iwama
- Department of Health Chemistry, The University of Tokyo Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Kuniyuki Kano
- Department of Health Chemistry, The University of Tokyo Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Sho Hasegawa
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan; Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Tsuyoshi Inoue
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan; Department of Physiology of Visceral Function and Body Fluid, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | | | - Junken Aoki
- Department of Health Chemistry, The University of Tokyo Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Yutaka Yatomi
- Department of Clinical Laboratory Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
| | - Reiko Inagi
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
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Wang H, Zhang S, Guo J. Lipotoxic Proximal Tubular Injury: A Primary Event in Diabetic Kidney Disease. Front Med (Lausanne) 2021; 8:751529. [PMID: 34760900 PMCID: PMC8573085 DOI: 10.3389/fmed.2021.751529] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 09/27/2021] [Indexed: 01/23/2023] Open
Abstract
The pathogenesis of diabetic nephropathy is a complex process that has a great relationship with lipotoxicity. Since the concept of “nephrotoxicity” was proposed, many studies have confirmed that lipotoxicity plays a significant role in the progression of diabetic nephropathy and causes various renal dysfunction. This review will make a brief summary of renal injury caused by lipotoxicity that occurs primarily and predominantly in renal tubules during diabetic progression, further leading to glomerular dysfunction. The latest research suggests that lipotoxicity-mediated tubular injury may be a major event in diabetic nephropathy.
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Affiliation(s)
- Hua Wang
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Shu Zhang
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jia Guo
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Department of Nephrology, Nephropathy Research Institutes of Zhengzhou University, Zhengzhou, China
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60
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Chen JH, Wu CH, Chiang CK. Therapeutic Approaches Targeting Proteostasis in Kidney Disease and Fibrosis. Int J Mol Sci 2021; 22:ijms22168674. [PMID: 34445377 PMCID: PMC8395452 DOI: 10.3390/ijms22168674] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 12/12/2022] Open
Abstract
Pathological insults usually disturb the folding capacity of cellular proteins and lead to the accumulation of misfolded proteins in the endoplasmic reticulum (ER), which leads to so-called “ER stress”. Increasing evidence indicates that ER stress acts as a trigger factor for the development and progression of many kidney diseases. The unfolded protein responses (UPRs), a set of molecular signals that resume proteostasis under ER stress, are thought to restore the adaptive process in chronic kidney disease (CKD) and renal fibrosis. Furthermore, the idea of targeting UPRs for CKD treatment has been well discussed in the past decade. This review summarizes the up-to-date literature regarding studies on the relationship between the UPRs, systemic fibrosis, and renal diseases. We also address the potential therapeutic possibilities of renal diseases based on the modulation of UPRs and ER proteostasis. Finally, we list some of the current UPR modulators and their therapeutic potentials.
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Affiliation(s)
- Jia-Huang Chen
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100233, Taiwan; (J.-H.C.); (C.-H.W.)
| | - Chia-Hsien Wu
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100233, Taiwan; (J.-H.C.); (C.-H.W.)
- Department of Physiology of Visceral Function and Body Fluid, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8523, Japan
| | - Chih-Kang Chiang
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100233, Taiwan; (J.-H.C.); (C.-H.W.)
- Department of Integrated Diagnostics & Therapeutics, National Taiwan University Hospital, Taipei 100225, Taiwan
- Center for Biotechnology, National Taiwan University, Taipei 10672, Taiwan
- Correspondence: ; Tel.: +886-2-2312-3456 (ext. 88347)
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Fujii R, Hasegawa S, Maekawa H, Inoue T, Yoshioka K, Uni R, Ikeda Y, Nangaku M, Inagi R. Decreased IFT88 expression with primary cilia shortening causes mitochondrial dysfunction in cisplatin-induced tubular injury. Am J Physiol Renal Physiol 2021; 321:F278-F292. [PMID: 34338030 DOI: 10.1152/ajprenal.00673.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The relevance of primary cilia shortening in kidney disease and its pathomechanism are largely unknown. Tubular damage in acute kidney injury (AKI) is strongly associated with mitochondrial dysfunction. Thus, we investigated the interaction between primary cilia and mitochondria in cisplatin-induced AKI mouse models. We observed that the expression of intraflagellar transport 88 (IFT88), a ciliary maintenance protein, was decreased in the renal cortex following tubular damage due to cisplatin-induced AKI. This result was consistent with the decreased IFT88 expression in cisplatin-treated RPTEC/TERT1 cells (human primary proximal tubular cells) parallel to the shortening of primary cilia, suggesting a causative link between tubular damage and IFT88-mediated cilia regulation. To address the effect of impaired primary cilia with decreased IFT88 expression on tubular function, RPTEC/TERT1 cells treated with cisplatin and knocked down for IFT88 using siRNA (IFT88-KD) were assessed for phenotypic changes and mitochondrial metabolic function. Both cisplatin and IFT88-KD caused primary cilia shortening, downregulated mitochondrial oxidative phosphorylation capacity, and had defective fatty acid oxidation and decreased ATP production. Furthermore, IFT88 overexpression enhanced mitochondrial respiration, which partially counteracted cisplatin-induced defective fatty acid oxidation. These results are indicative of the contribution of IFT88 to mitochondrial homeostasis. Our findings suggest that tubular mitochondrial dysfunction in cisplatin-induced AKI is mediated, at least in part, by a decrease in IFT88 expression with primary cilia shortening. That is, tubular mitochondrial damage followed by tubular injury in AKI may occur through alteration of IFT88 expression and subsequent ciliary shortening in tubular cells.NEW & NOTEWORTHY Here, we demonstrated organelle cross-talk between primary cilia and mitochondria of proximal tubular cells in cisplatin-induced acute kidney injury. The primary cilia-mitochondria interaction may open new avenues for the development of novel therapeutic approaches in the treatment of acute kidney injury.
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Affiliation(s)
- Rie Fujii
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.,Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Sho Hasegawa
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.,Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Hiroshi Maekawa
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.,Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Tsuyoshi Inoue
- Department of Physiology of Visceral Function and Body Fluid, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Kentaro Yoshioka
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.,Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.,R&D Division, Kyowa Kirin Company, Limited, Tokyo, Japan
| | - Rie Uni
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.,Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Yoichiro Ikeda
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Reiko Inagi
- Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
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62
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Noels H, Lehrke M, Vanholder R, Jankowski J. Lipoproteins and fatty acids in chronic kidney disease: molecular and metabolic alterations. Nat Rev Nephrol 2021; 17:528-542. [PMID: 33972752 DOI: 10.1038/s41581-021-00423-5] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2021] [Indexed: 02/06/2023]
Abstract
Chronic kidney disease (CKD) induces modifications in lipid and lipoprotein metabolism and homeostasis. These modifications can promote, modulate and/or accelerate CKD and secondary cardiovascular disease (CVD). Lipid and lipoprotein abnormalities - involving triglyceride-rich lipoproteins, LDL and/or HDL - not only involve changes in concentration but also changes in molecular structure, including protein composition, incorporation of small molecules and post-translational modifications. These alterations modify the function of lipoproteins and can trigger pro-inflammatory and pro-atherogenic processes, as well as oxidative stress. Serum fatty acid levels are also often altered in patients with CKD and lead to changes in fatty acid metabolism - a key process in intracellular energy production - that induce mitochondrial dysfunction and cellular damage. These fatty acid changes might not only have a negative impact on the heart, but also contribute to the progression of kidney damage. The presence of these lipoprotein alterations within a biological environment characterized by increased inflammation and oxidative stress, as well as the competing risk of non-atherosclerotic cardiovascular death as kidney function declines, has important therapeutic implications. Additional research is needed to clarify the pathophysiological link between lipid and lipoprotein modifications, and kidney dysfunction, as well as the genesis and/or progression of CVD in patients with kidney disease.
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Affiliation(s)
- Heidi Noels
- Institute for Molecular Cardiovascular Research, RWTH Aachen University, University Hospital, Aachen, Germany
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, Netherlands
| | - Michael Lehrke
- Department of Internal Medicine I, RWTH Aachen University, University Hospital, Aachen, Germany
| | - Raymond Vanholder
- Nephrology Section, Department of Internal Medicine and Pediatrics, University Hospital, Ghent, Belgium
| | - Joachim Jankowski
- Institute for Molecular Cardiovascular Research, RWTH Aachen University, University Hospital, Aachen, Germany.
- Department of Pathology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht University, Maastricht, Netherlands.
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63
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Jia Z, Wang K, Zhang Y, Duan Y, Xiao K, Liu S, Ding X. Icariin Ameliorates Diabetic Renal Tubulointerstitial Fibrosis by Restoring Autophagy via Regulation of the miR-192-5p/GLP-1R Pathway. Front Pharmacol 2021; 12:720387. [PMID: 34349660 PMCID: PMC8326523 DOI: 10.3389/fphar.2021.720387] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 07/09/2021] [Indexed: 12/24/2022] Open
Abstract
Tubulointerstitial fibrosis is one of the most common pathological features of diabetic nephropathy. Autophagy, an intracellular mechanism to remove damaged or dysfunctional cell parts and maintain metabolic homeostasis, is inhibited in diabetic neuropathy. Icariin is a traditional Chinese medicine extract known for nourishing the kidney and reinforcing Yang. In this study, we investigated the effects and mechanism of Icariin on renal function, autophagy, and fibrosis in type 2 diabetic nephropathic rats and in high-glucose-incubated human renal tubular epithelial cells and rat renal fibroblasts (in vitro). Icariin improved diabetes, renal function, restored autophagy, and alleviated fibrosis in type 2 diabetic neuropathic rats and in vitro. After we applied autophagy-related gene 5-small interfering RNA, we found that fibrosis improvement by Icariin was related to autophagy restoration. By detecting serum sex hormone levels, and using dihydrotestosterone, siRNA for androgen receptor, and the androgen receptor antagonist Apalutamide (ARN-509), we found that Icariin had an androgen-like effect and restored autophagy and reduced fibrosis by regulating the androgen receptor. In addition, miR-192-5p levels were increased under high glucose but reduced after dihydrotestosterone and Icariin treatment. Furthermore, dihydrotestosterone and Icariin inhibited miR-192-5p overexpression-induced fibrosis production and autophagy limitation. Glucagon-like peptide-1 receptor (GLP-1R) was downregulated by high glucose and overexpression of miR-192-5p and could be restored by dihydrotestosterone and Icariin. By using ARN-509, we found that Icariin increased GLP-1R expression by regulating the androgen receptor. GLP-1R-siRNA transfection weakened the effects of Icariin on autophagy and fibrosis. These findings indicate that Icariin alleviates tubulointerstitial fibrosis by restoring autophagy through the miR-192-5p/GLP-1R pathway and is a novel therapeutic option for diabetic fibrosis.
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Affiliation(s)
- Zhirong Jia
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Kaiwei Wang
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Yameng Zhang
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Yalei Duan
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Kang Xiao
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Shuo Liu
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Xuansheng Ding
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China.,Precision Medicine Laboratory, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
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64
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Fibrosis, the Bad Actor in Cardiorenal Syndromes: Mechanisms Involved. Cells 2021; 10:cells10071824. [PMID: 34359993 PMCID: PMC8307805 DOI: 10.3390/cells10071824] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/08/2021] [Accepted: 07/13/2021] [Indexed: 02/06/2023] Open
Abstract
Cardiorenal syndrome is a term that defines the complex bidirectional nature of the interaction between cardiac and renal disease. It is well established that patients with kidney disease have higher incidence of cardiovascular comorbidities and that renal dysfunction is a significant threat to the prognosis of patients with cardiac disease. Fibrosis is a common characteristic of organ injury progression that has been proposed not only as a marker but also as an important driver of the pathophysiology of cardiorenal syndromes. Due to the relevance of fibrosis, its study might give insight into the mechanisms and targets that could potentially be modulated to prevent fibrosis development. The aim of this review was to summarize some of the pathophysiological pathways involved in the fibrotic damage seen in cardiorenal syndromes, such as inflammation, oxidative stress and endoplasmic reticulum stress, which are known to be triggers and mediators of fibrosis.
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65
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Nangaku M. Founding papers of current nephrology: from acute kidney injury to diabetic kidney disease. Kidney Int 2021; 98:6-9. [PMID: 32571493 DOI: 10.1016/j.kint.2020.03.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 03/26/2020] [Indexed: 01/12/2023]
Affiliation(s)
- Masaomi Nangaku
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
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66
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Cheng N, Shi JH, Jin Y, Shi YB, Liu XD, Zhang HP, Cao SL, Yang H, Guo WZ, Zhang SJ. Pharmacological Activating Transcription Factor 6 Activation Is Beneficial for Liver Retrieval With ex vivo Normothermic Mechanical Perfusion From Cardiac Dead Donor Rats. Front Surg 2021; 8:665260. [PMID: 34222317 PMCID: PMC8249577 DOI: 10.3389/fsurg.2021.665260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 05/24/2021] [Indexed: 01/17/2023] Open
Abstract
Background: Normothermic machine perfusion (NMP) could be beneficial for organ retrieval from donors after cardiac death (DCD). Activating transcription factor 6 (ATF6) was recently shown to mitigate liver ischemia/reperfusion injury and confer protection. The aims of this study were to assess the implication of ATF6 in liver retrieval from DCD rat livers with NMP and explore the effect of pharmacologic ATF-6 activation on liver retrieval. Methods: The livers from DCD rats were exposed to 30 min of warm ischemia and 8 h cold preservation followed by 2 h NMP with or without an ATF6 activator in the perfusate. Perfusates and livers were harvested to detect ATF6 expression, liver function, and inflammation. Results: DCD livers with NMP were associated with ATF6 overexpression and activation based on IHC and WB (P < 0.05). The ATF6 activator downregulated perfusate aminotransferases, decreased the Suzuki score, downregulated CD68 and MPO based on IHC, induced the expression of cytochrome c in mitochondria and inhibited the expression of cytochrome c in cytoplasm based on WB, reduced TNFα and IL-6 levels based on ELISA, decreased levels of MDA, GSSG and ATP, and increased SOD activity and GSH levels in the perfused livers (P < 0.05). Conclusion: ATF6 is important for liver retrieval, and an exogenous ATF6 activator accelerates liver retrieval from DCD rats in an ex vivo NMP model.
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Affiliation(s)
- Nuo Cheng
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Ji-Hua Shi
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Yang Jin
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Yuan-Bin Shi
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Xu-Dong Liu
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Hua-Peng Zhang
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Sheng-Li Cao
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Han Yang
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Wen-Zhi Guo
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Shui-Jun Zhang
- Department of Hepatobiliary and Pancreatic Surgery, Zhengzhou Key Laboratory for HPB Diseases and Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
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67
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DNA demethylase Tet2 suppresses cisplatin-induced acute kidney injury. Cell Death Dis 2021; 7:167. [PMID: 34226503 PMCID: PMC8257623 DOI: 10.1038/s41420-021-00528-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/08/2021] [Accepted: 05/23/2021] [Indexed: 02/06/2023]
Abstract
Demethylase Tet2 plays a vital role in the immune response. Acute kidney injury (AKI) initiation and maintenance phases are marked by inflammatory responses and leukocyte recruitment in endothelial and tubular cell injury processes. However, the role of Tet2 in AKI is poorly defined. Our study determined the degree of renal tissue damage associated with Tet2 gene expression levels in a cisplatin-induced AKI mice model. Tet2-knockout (KO) mice with cisplatin treatment experienced severe tubular necrosis and dilatation, inflammation, and AKI markers' expression levels than the wild-type mice. In addition, the administration of Tet2 plasmid protected Tet2-KO mice from cisplatin-induced nephrotoxicity, but not Tet2-catalytic-dead mutant. Tet2 KO was associated with a change in metabolic pathways like retinol, arachidonic acid, linolenic acid metabolism, and PPAR signaling pathway in the cisplatin-induced mice model. Tet2 expression is also downregulated in other AKI mice models and clinical samples. Thus, our results indicate that Tet2 has a renal protective effect during AKI by regulating metabolic and inflammatory responses through the PPAR signaling pathway.
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68
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Gao Y, Hu JH, Liang XD, Chen J, Liu CC, Liu YY, Cheng Y, Go YY, Zhou B. Curcumin inhibits classical swine fever virus replication by interfering with lipid metabolism. Vet Microbiol 2021; 259:109152. [PMID: 34146894 DOI: 10.1016/j.vetmic.2021.109152] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 06/06/2021] [Indexed: 11/26/2022]
Abstract
Although previous reports have shown that Curcumin inhibits many viruses, including some important members of different genera of Flaviviridae family (Japanese encephalitis virus, dengue virus and hepatitis C virus), the antiviral activity of curcumin against Classical swine fever virus (CSFV), which belongs to Pestivirus genus, is still unclear. In this study, we found that curcumin inhibited CSFV replication in a dose-dependent manner, but had no effect on virus adsorption and entry. Furthermore, the results showed that curcumin inhibited the expression of FASN, one of the key enzymes of fatty acid synthesis pathway, thereby, causing the reduction of the production of LDs upon infection. To this end, we detected transcription factor 6 (ATF6), the key factor of regulating lipid metabolism along with other related molecules (CHOP and GPR78) and found that curcumin significantly impaired the gene synthesis of ATF6, while CSFV infection promoted ATF6 expression. Therefore, it is confirmed that curcumin inhibited CSFV replication by interfere lipid metabolism. In addition, our subsequent studies found that curcumin played an antiviral role by promoting the innate immune independent of NF-κB signaling pathway. Taken together, our finding highlights that curcumin is a potential candidate drug against CSFV for controlling CSF.
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Affiliation(s)
- Ya Gao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jia-Huan Hu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Xiao-Dong Liang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jing Chen
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Chun-Chun Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Ya-Yun Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Yan Cheng
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Yun Young Go
- Department of Infectious Diseases and Public Health, City University of Hong Kong, Hong Kong, China
| | - Bin Zhou
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
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69
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Varghese DS, Ali BR. Pathological Crosstalk Between Oxidized LDL and ER Stress in Human Diseases: A Comprehensive Review. Front Cell Dev Biol 2021; 9:674103. [PMID: 34124059 PMCID: PMC8187772 DOI: 10.3389/fcell.2021.674103] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/26/2021] [Indexed: 02/05/2023] Open
Abstract
The oxidative modification of the major cholesterol carrying lipoprotein, oxLDL, is a biomarker as well as a pathological factor in cardiovascular diseases (CVD), type 2 diabetes mellitus (T2DM), obesity and other metabolic diseases. Perturbed cellular homeostasis due to physiological, pathological and pharmacological factors hinder the proper functioning of the endoplasmic reticulum (ER), which is the major hub for protein folding and processing, lipid biosynthesis and calcium storage, thereby leading to ER stress. The cellular response to ER stress is marked by a defensive mechanism called unfolded protein response (UPR), wherein the cell adapts strategies that favor survival. Under conditions of excessive ER stress, when the survival mechanisms fail to restore balance, UPR switches to apoptosis and eliminates the defective cells. ER stress is a major hallmark in metabolic syndromes such as diabetes, non-alcoholic fatty liver disease (NAFLD), neurological and cardiovascular diseases. Though the pathological link between oxLDL and ER stress in cardiovascular diseases is well-documented, its involvement in other diseases is still largely unexplored. This review provides a deep insight into the common mechanisms in the pathogenicity of diseases involving oxLDL and ER stress as key players. In addition, the potential therapeutic intervention of the targets implicated in the pathogenic processes are also explored.
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Affiliation(s)
- Divya Saro Varghese
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Genetics and Genomics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Zayed Bin Sultan Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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70
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Takata T, Isomoto H. Pleiotropic Effects of Sodium-Glucose Cotransporter-2 Inhibitors: Renoprotective Mechanisms beyond Glycemic Control. Int J Mol Sci 2021; 22:ijms22094374. [PMID: 33922132 PMCID: PMC8122753 DOI: 10.3390/ijms22094374] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 04/14/2021] [Accepted: 04/20/2021] [Indexed: 12/30/2022] Open
Abstract
Diabetes mellitus is a major cause of chronic kidney disease and end-stage renal disease. However, the management of chronic kidney disease, particularly diabetes, requires vast improvements. Recently, sodium-glucose cotransporter-2 (SGLT2) inhibitors, originally developed for the treatment of diabetes, have been shown to protect against kidney injury via glycemic control, as well as various other mechanisms, including blood pressure and hemodynamic regulation, protection from lipotoxicity, and uric acid control. As such, regulation of these mechanisms is recommended as an effective multidisciplinary approach for the treatment of diabetic patients with kidney disease. Thus, SGLT2 inhibitors are expected to become key drugs for treating diabetic kidney disease. This review summarizes the recent clinical evidence pertaining to SGLT2 inhibitors as well as the mechanisms underlying their renoprotective effects. Hence, the information contained herein will advance the current understanding regarding the pleiotropic effects of SGLT2 inhibitors, while promoting future research in the field.
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71
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Li C, Chen YM. Endoplasmic Reticulum-Associated Biomarkers for Molecular Phenotyping of Rare Kidney Disease. Int J Mol Sci 2021; 22:2161. [PMID: 33671535 PMCID: PMC7926397 DOI: 10.3390/ijms22042161] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 01/31/2021] [Accepted: 02/02/2021] [Indexed: 12/20/2022] Open
Abstract
The endoplasmic reticulum (ER) is the central site for folding, post-translational modifications, and transport of secretory and membrane proteins. An imbalance between the load of misfolded proteins and the folding capacity of the ER causes ER stress and an unfolded protein response. Emerging evidence has shown that ER stress or the derangement of ER proteostasis contributes to the development and progression of a variety of glomerular and tubular diseases. This review gives a comprehensive summary of studies that have elucidated the role of the three ER stress signaling pathways, including inositol-requiring enzyme 1 (IRE1), protein kinase R-like ER kinase (PERK), and activating transcription factor 6 (ATF6) signaling in the pathogenesis of kidney disease. In addition, we highlight the recent discovery of ER-associated biomarkers, including MANF, ERdj3, ERdj4, CRELD2, PDIA3, and angiogenin. The implementation of these novel biomarkers may accelerate early diagnosis and therapeutic intervention in rare kidney disease.
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Affiliation(s)
| | - Ying Maggie Chen
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA;
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72
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Bugarski M, Ghazi S, Polesel M, Martins JR, Hall AM. Changes in NAD and Lipid Metabolism Drive Acidosis-Induced Acute Kidney Injury. J Am Soc Nephrol 2021; 32:342-356. [PMID: 33478973 PMCID: PMC8054907 DOI: 10.1681/asn.2020071003] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 10/30/2020] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The kidney plays an important role in maintaining normal blood pH. Metabolic acidosis (MA) upregulates the pathway that mitochondria in the proximal tubule (PT) use to produce ammonia and bicarbonate from glutamine, and is associated with AKI. However, the extent to which MA causes AKI, and thus whether treating MA would be beneficial, is unclear. METHODS Gavage with ammonium chloride induced acute MA. Multiphoton imaging of mitochondria (NADH/membrane potential) and transport function (dextran/albumin uptake), oxygen consumption rate (OCR) measurements in isolated tubules, histologic analysis, and electron microscopy in fixed tissue, and urinary biomarkers (KIM-1/clara cell 16) assessed tubular cell structure and function in mouse kidney cortex. RESULTS MA induces an acute change in NAD redox state (toward oxidation) in PT mitochondria, without changing the mitochondrial energization state. This change is associated with a switch toward complex I activity and decreased maximal OCR, and a major alteration in normal lipid metabolism, resulting in marked lipid accumulation in PTs and the formation of large multilamellar bodies. These changes, in turn, lead to acute tubular damage and a severe defect in solute uptake. Increasing blood pH with intravenous bicarbonate substantially improves tubular function, whereas preinjection with the NAD precursor nicotinamide (NAM) is highly protective. CONCLUSIONS MA induces AKI via changes in PT NAD and lipid metabolism, which can be reversed or prevented by treatment strategies that are viable in humans. These findings might also help to explain why MA accelerates decline in function in CKD.
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Affiliation(s)
- Milica Bugarski
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Susan Ghazi
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | | | - Joana R. Martins
- Institute of Anatomy, University of Zurich, Zurich, Switzerland,Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Andrew M. Hall
- Institute of Anatomy, University of Zurich, Zurich, Switzerland,Department of Nephrology, University Hospital Zurich, Zurich, Switzerland
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73
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Gastrin, via activation of PPARα, protects the kidney against hypertensive injury. Clin Sci (Lond) 2021; 135:409-427. [PMID: 33458737 DOI: 10.1042/cs20201340] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/05/2021] [Accepted: 01/15/2021] [Indexed: 12/16/2022]
Abstract
Hypertensive nephropathy (HN) is a common cause of end-stage renal disease with renal fibrosis; chronic kidney disease is associated with elevated serum gastrin. However, the relationship between gastrin and renal fibrosis in HN is still unknown. We, now, report that mice with angiotensin II (Ang II)-induced HN had increased renal cholecystokinin receptor B (CCKBR) expression. Knockout of CCKBR in mice aggravated, while long-term subcutaneous infusion of gastrin ameliorated the renal injury and interstitial fibrosis in HN and unilateral ureteral obstruction (UUO). The protective effects of gastrin on renal fibrosis can be independent of its regulation of blood pressure, because in UUO, gastrin decreased renal fibrosis without affecting blood pressure. Gastrin treatment decreased Ang II-induced renal tubule cell apoptosis, reversed Ang II-mediated inhibition of macrophage efferocytosis, and reduced renal inflammation. A screening of the regulatory factors of efferocytosis showed involvement of peroxisome proliferator-activated receptor α (PPAR-α). Knockdown of PPAR-α by shRNA blocked the anti-fibrotic effect of gastrin in vitro in mouse renal proximal tubule cells and macrophages. Immunofluorescence microscopy, Western blotting, luciferase reporter, and Cut&tag-qPCR analyses showed that CCKBR may be a transcription factor of PPAR-α, because gastrin treatment induced CCKBR translocation from cytosol to nucleus, binding to the PPAR-α promoter region, and increasing PPAR-α gene transcription. In conclusion, gastrin protects against HN by normalizing blood pressure, decreasing renal tubule cell apoptosis, and increasing macrophage efferocytosis. Gastrin-mediated CCKBR nuclear translocation may make it act as a transcription factor of PPAR-α, which is a novel signaling pathway. Gastrin may be a new potential drug for HN therapy.
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74
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Delgado-Valero B, de la Fuente-Chávez L, Romero-Miranda A, Visitación Bartolomé M, Ramchandani B, Islas F, Luaces M, Cachofeiro V, Martínez-Martínez E. Role of endoplasmic reticulum stress in renal damage after myocardial infarction. Clin Sci (Lond) 2021; 135:143-159. [PMID: 33355632 DOI: 10.1042/cs20201137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 12/17/2020] [Accepted: 12/23/2020] [Indexed: 02/06/2023]
Abstract
Myocardial infarction (MI) is associated with renal alterations resulting in poor outcomes in patients with MI. Renal fibrosis is a potent predictor of progression in patients and is often accompanied by inflammation and oxidative stress; however, the mechanisms involved in these alterations are not well established. Endoplasmic reticulum (ER) plays a central role in protein processing and folding. An accumulation of unfolded proteins leads to ER dysfunction, termed ER stress. Since the kidney is the organ with highest protein synthesis fractional rate, we herein investigated the effects of MI on ER stress at renal level, as well as the possible role of ER stress on renal alterations after MI. Patients and MI male Wistar rats showed an increase in the kidney injury marker neutrophil gelatinase-associated lipocalin (NGAL) at circulating level or renal level respectively. Four weeks post-MI rats presented renal fibrosis, oxidative stress and inflammation accompanied by ER stress activation characterized by enhanced immunoglobin binding protein (BiP), protein disulfide-isomerase A6 (PDIA6) and activating transcription factor 6-alpha (ATF6α) protein levels. In renal fibroblasts, palmitic acid (PA; 50-200 µM) and angiotensin II (Ang II; 10-8 to 10-6M) promoted extracellular matrix, superoxide anion production and inflammatory markers up-regulation. The presence of the ER stress inhibitor, 4-phenylbutyric acid (4-PBA; 4 µM), was able to prevent all of these modifications in renal cells. Therefore, the data show that ER stress mediates the deleterious effects of PA and Ang II in renal cells and support the potential role of ER stress on renal alterations associated with MI.
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Affiliation(s)
- Beatriz Delgado-Valero
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid-Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
| | - Lucía de la Fuente-Chávez
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid-Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
| | - Ana Romero-Miranda
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid-Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
| | - María Visitación Bartolomé
- Departmento de Inmunología, Oftalmología y Otorrinolaringología, Facultad de Psicología, Universidad Complutense Madrid, Spain
- Ciber de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
| | - Bunty Ramchandani
- Servicio de Cirugía Cardiaca Infantil, Hospital La Paz, Madrid, Spain
| | - Fabián Islas
- Servicio de Cardiología, Instituto Cardiovascular, Hospital Clínico San Carlos, Madrid, Spain
| | - María Luaces
- Servicio de Cardiología, Instituto Cardiovascular, Hospital Clínico San Carlos, Madrid, Spain
| | - Victoria Cachofeiro
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid-Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
- Ciber de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
| | - Ernesto Martínez-Martínez
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid-Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
- Ciber de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
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75
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Moncan M, Mnich K, Blomme A, Almanza A, Samali A, Gorman AM. Regulation of lipid metabolism by the unfolded protein response. J Cell Mol Med 2021; 25:1359-1370. [PMID: 33398919 PMCID: PMC7875919 DOI: 10.1111/jcmm.16255] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/17/2020] [Accepted: 12/18/2020] [Indexed: 12/17/2022] Open
Abstract
The endoplasmic reticulum (ER) is the site of protein folding and secretion, Ca2+ storage and lipid synthesis in eukaryotic cells. Disruption to protein folding or Ca2+ homeostasis in the ER leads to the accumulation of unfolded proteins, a condition known as ER stress. This leads to activation of the unfolded protein response (UPR) pathway in order to restore protein homeostasis. Three ER membrane proteins, namely inositol‐requiring enzyme 1 (IRE1), protein kinase RNA‐like ER kinase (PERK) and activating transcription factor 6 (ATF6), sense the accumulation of unfolded/misfolded proteins and are activated, initiating an integrated transcriptional programme. Recent literature demonstrates that activation of these sensors can alter lipid enzymes, thus implicating the UPR in the regulation of lipid metabolism. Given the presence of ER stress and UPR activation in several diseases including cancer and neurodegenerative diseases, as well as the growing recognition of altered lipid metabolism in disease, it is timely to consider the role of the UPR in the regulation of lipid metabolism. This review provides an overview of the current knowledge on the impact of the three arms of the UPR on the synthesis, function and regulation of fatty acids, triglycerides, phospholipids and cholesterol.
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Affiliation(s)
- Matthieu Moncan
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Katarzyna Mnich
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Arnaud Blomme
- Laboratory of Cancer Signaling, GIGA-institute, University of Liège, Liège, Belgium
| | - Aitor Almanza
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Afshin Samali
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Adrienne M Gorman
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
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76
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Libby AE, Jones B, Lopez-Santiago I, Rowland E, Levi M. Nuclear receptors in the kidney during health and disease. Mol Aspects Med 2020; 78:100935. [PMID: 33272705 DOI: 10.1016/j.mam.2020.100935] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/24/2020] [Accepted: 11/16/2020] [Indexed: 02/06/2023]
Abstract
Over the last 30 years, nuclear receptors (NRs) have been increasingly recognized as key modulators of systemic homeostasis and as contributing factors in many diseases. In the kidney, NRs play numerous important roles in maintaining homeostasis-many of which continue to be unraveled. As "master regulators", these important transcription factors integrate and coordinate many renal processes such as circadian responses, lipid metabolism, fatty acid oxidation, glucose handling, and inflammatory responses. The use of recently-developed genetic tools and small molecule modulators have allowed for detailed studies of how renal NRs contribute to kidney homeostasis. Importantly, while NRs are intimately involved in proper kidney function, they are also implicated in a variety of renal diseases such as diabetes, acute kidney injury, and other conditions such as aging. In the last 10 years, our understanding of renal disease etiology and progression has been greatly shaped by knowledge regarding how NRs are dysregulated in these conditions. Importantly, NRs have also become attractive therapeutic targets for attenuation of renal diseases, and their modulation for this purpose has been the subject of intense investigation. Here, we review the role in health and disease of six key renal NRs including the peroxisome proliferator-activated receptors (PPAR), estrogen-related receptors (ERR), the farnesoid X receptors (FXR), estrogen receptors (ER), liver X receptors (LXR), and vitamin D receptors (VDR) with an emphasis on recent findings over the last decade. These NRs have generated a wealth of data over the last 10 years that demonstrate their crucial role in maintaining normal renal homeostasis as well as their capacity to modulate disease progression.
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Affiliation(s)
- Andrew E Libby
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, 3900 Reservoir Rd, Washington, DC, 20007, USA.
| | - Bryce Jones
- Department of Pharmacology and Physiology, Georgetown University, 3900 Reservoir Rd, Washington, DC, 20007, USA.
| | - Isabel Lopez-Santiago
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, 3900 Reservoir Rd, Washington, DC, 20007, USA.
| | - Emma Rowland
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, 3900 Reservoir Rd, Washington, DC, 20007, USA.
| | - Moshe Levi
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, 3900 Reservoir Rd, Washington, DC, 20007, USA.
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77
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Hasegawa S, Inagi R. Organelle Stress and Crosstalk in Kidney Disease. KIDNEY360 2020; 1:1157-1164. [PMID: 35368784 PMCID: PMC8815491 DOI: 10.34067/kid.0002442020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/05/2020] [Indexed: 12/19/2022]
Abstract
Organelles play important roles in maintaining cellular homeostasis. Organelle stress responses, especially in mitochondria, endoplasmic reticula (ER), and primary cilia, are deeply involved in kidney disease pathophysiology. Mitochondria are the center of energy production in most eukaryotic cells. Renal proximal tubular cells are highly energy demanding and abundant in mitochondria. Mitochondrial dysfunctions in association with energy metabolism alterations produce reactive oxygen species and promote inflammation in proximal tubular cells, resulting in progression of kidney disease. The ER play critical roles in controlling protein quality. Unfolded protein response (UPR) pathways are the adaptive response to ER stress for maintaining protein homeostasis. UPR pathway dysregulation under pathogenic ER stress often occurs in glomerular and tubulointerstitial cells and promotes progression of kidney disease. The primary cilia sense extracellular signals and maintain calcium homeostasis in cells. Dysfunction of the primary cilia in autosomal dominant polycystic kidney disease reduces the calcium concentration in proximal tubular cells, leading to increased cell proliferation and retention of cyst fluid. In recent years, the direct interaction at membrane contact sites has received increased attention in association with the development of imaging technologies. The part of the ER that is directly connected to mitochondria is termed the mitochondria-associated ER membrane (MAM), which regulates calcium homeostasis and phospholipid metabolism in cells. Disruption of MAM integrity collapses cellular homeostasis and leads to diseases such as diabetes and Alzheimer disease. This review summarizes recent research on organelle stress and crosstalk, and their involvement in kidney disease pathophysiology. In addition, potential treatment options that target organelle stress responses are discussed.
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Affiliation(s)
- Sho Hasegawa
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
- Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Reiko Inagi
- Division of Chronic Kidney Disease Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
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78
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Jiang M, Bai M, Lei J, Xie Y, Xu S, Jia Z, Zhang A. Mitochondrial dysfunction and the AKI-to-CKD transition. Am J Physiol Renal Physiol 2020; 319:F1105-F1116. [PMID: 33073587 DOI: 10.1152/ajprenal.00285.2020] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Acute kidney injury (AKI) has been widely recognized as an important risk factor for the occurrence and development of chronic kidney disease (CKD). Even milder AKI has adverse consequences and could progress to renal fibrosis, which is the ultimate common pathway for various terminal kidney diseases. Thus, it is urgent to develop a strategy to hinder the transition from AKI to CKD. Some mechanisms of the AKI-to-CKD transition have been revealed, such as nephron loss, cell cycle arrest, persistent inflammation, endothelial injury with vascular rarefaction, and epigenetic changes. Previous studies have elucidated the pivotal role of mitochondria in acute injuries and demonstrated that the fitness of this organelle is a major determinant in both the pathogenesis and recovery of organ function. Recent research has suggested that damage to mitochondrial function in early AKI is a crucial factor leading to tubular injury and persistent renal insufficiency. Dysregulation of mitochondrial homeostasis, alterations in bioenergetics, and organelle stress cross talk contribute to the AKI-to-CKD transition. In this review, we focus on the pathophysiology of mitochondria in renal recovery after AKI and progression to CKD, confirming that targeting mitochondria represents a potentially effective therapeutic strategy for the progression of AKI to CKD.
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Affiliation(s)
- Mingzhu Jiang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.,Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Mi Bai
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.,Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China.,Nanjing Key Lab of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Juan Lei
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.,Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Yifan Xie
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.,Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Shuang Xu
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.,Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
| | - Zhanjun Jia
- Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China.,Nanjing Key Lab of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Aihua Zhang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.,Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing, China
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79
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Ricciardi CA, Gnudi L. The endoplasmic reticulum stress and the unfolded protein response in kidney disease: Implications for vascular growth factors. J Cell Mol Med 2020; 24:12910-12919. [PMID: 33067928 PMCID: PMC7701511 DOI: 10.1111/jcmm.15999] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/14/2020] [Accepted: 09/30/2020] [Indexed: 12/14/2022] Open
Abstract
Acute kidney injury (AKI) and chronic kidney disease (CKD) represent an important challenge for healthcare providers. The identification of new biomarkers/pharmacological targets for kidney disease is required for the development of more effective therapies. Several studies have shown the importance of the endoplasmic reticulum (ER) stress in the pathophysiology of AKI and CKD. ER is a cellular organelle devolved to protein biosynthesis and maturation, and cellular detoxification processes which are activated in response to an insult. This review aimed to dissect the cellular response to ER stress which manifests with activation of the unfolded protein response (UPR) with its major branches, namely PERK, IRE1α, ATF6 and the interplay between ER and mitochondria in the pathophysiology of kidney disease. Further, we will discuss the relationship between mediators of renal injury (with specific focus on vascular growth factors) and ER stress and UPR in the pathophysiology of both AKI and CKD with the aim to propose potential new targets for treatment for kidney disease.
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Affiliation(s)
- Carlo Alberto Ricciardi
- King's College of London, Faculty of Life Sciences & Medicine, School of Cardiovascular Medicine & Sciences, Section Vascular Biology and Inflammation, British Heart Foundation Centre for Research Excellence, London, UK
| | - Luigi Gnudi
- King's College of London, Faculty of Life Sciences & Medicine, School of Cardiovascular Medicine & Sciences, Section Vascular Biology and Inflammation, British Heart Foundation Centre for Research Excellence, London, UK
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80
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Nicolaou O, Kousios A, Sokratous K, Potamiti L, Koniali L, Neophytou G, Papacharalampous R, Zanti M, Ioannou K, Hadjisavvas A, Stingl C, Luider TM, Kyriacou K. Alport syndrome: Proteomic analysis identifies early molecular pathway alterations in Col4a3 knock out mice. Nephrology (Carlton) 2020; 25:937-949. [PMID: 32743880 PMCID: PMC7754404 DOI: 10.1111/nep.13764] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 07/06/2020] [Accepted: 07/26/2020] [Indexed: 01/02/2023]
Abstract
AIM Alport syndrome (AS) is the second most common hereditary kidney disease caused by mutations in collagen IV genes. Patients present with microhaematuria that progressively leads to proteinuria and end stage renal disease. Currently, no specific treatment exists for AS. Using mass spectrometry based proteomics, we aimed to detect early alterations in molecular pathways implicated in AS before the stage of overt proteinuria, which could be amenable to therapeutic intervention. METHODS Kidneys were harvested from male Col4a3-/- knock out and sex and age-matched Col4a3+/+ wild-type mice at 4 weeks of age. Purified peptides were separated by liquid chromatography and analysed by high resolution mass spectrometry. The Cytoscape bioinformatics tool was used for function enrichment and pathway analysis. PPARα expression levels were evaluated by immunofluorescence and immunoblotting. RESULTS Proteomic analysis identified 415 significantly differentially expressed proteins, which were mainly involved in metabolic and cellular processes, the extracellular matrix, binding and catalytic activity. Pathway enrichment analysis revealed among others, downregulation of the proteasome and PPAR pathways. PPARα protein expression levels were observed to be downregulated in Alport mice, supporting further the results of the discovery proteomics. CONCLUSION This study provides additional evidence that alterations in proteins which participate in cellular metabolism and mitochondrial homeostasis in kidney cells are early events in the development of chronic kidney disease in AS. Of note is the dysregulation of the PPAR pathway, which is amenable to therapeutic intervention and provides a new potential target for therapy in AS.
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Affiliation(s)
- Orthodoxia Nicolaou
- Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Andreas Kousios
- Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Renal and Transplant Centre, Hammersmith Hospital, Imperial College Healthcare NHS Trust, London, UK
| | - Kleitos Sokratous
- Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Louiza Potamiti
- Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Lola Koniali
- Department of Molecular Genetics Thalassemia, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - George Neophytou
- Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Revekka Papacharalampous
- Department of Neurology Clinic A, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Maria Zanti
- Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Bioinformatics Group, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Kyriakos Ioannou
- Department of Nephrology, Apollonion Private Hospital, Nicosia, Cyprus.,School of Medicine, European University, Nicosia, Cyprus
| | - Andreas Hadjisavvas
- Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Christoph Stingl
- Laboratory of Neuro-Oncology, Clinical and Cancer Proteomics, Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, CN, The Netherlands
| | - Theo M Luider
- Laboratory of Neuro-Oncology, Clinical and Cancer Proteomics, Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, CN, The Netherlands
| | - Kyriacos Kyriacou
- Cyprus School of Molecular Medicine, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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81
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Inagi R. The Implication of Organelle Cross Talk in AKI. Nephron Clin Pract 2020; 144:634-637. [PMID: 32702704 DOI: 10.1159/000508639] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 05/08/2020] [Indexed: 11/19/2022] Open
Abstract
Organelle stress, such as mitochondrial or endoplasmic reticulum damage, plays a crucial role in the pathogenesis of acute kidney injury (AKI). Further, persistent organelle stress, which causes metabolic abnormality followed by inflammation and fibrosis, is an important mediator of AKI-to-CKD transition. Organelle stress closely links to the derangement of organelle cross talk. Organelles intricately interact with each other under the physiological conditions to maintain their function each other and subsequent cell fate. Organelle stress and their cross talk are now a focus of intensive researches in the field of AKI as they are in the field of CKD.
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Affiliation(s)
- Reiko Inagi
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan, .,Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan,
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82
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Tan JH, Cao RC, Zhou L, Zhou ZT, Chen HJ, Xu J, Chen XM, Jin YC, Lin JY, Zeng JL, Li SJ, Luo M, Hu GD, Yang XB, Jin J, Zhang GW. ATF6 aggravates acinar cell apoptosis and injury by regulating p53/AIFM2 transcription in Severe Acute Pancreatitis. Theranostics 2020; 10:8298-8314. [PMID: 32724472 PMCID: PMC7381726 DOI: 10.7150/thno.46934] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 05/22/2020] [Indexed: 02/06/2023] Open
Abstract
Background: There is no curative therapy for severe acute pancreatitis (SAP) due to poor understanding of its molecular mechanisms. Endoplasmic reticulum (ER) stress is involved in SAP and increased expression of ATF6 has been detected in SAP patients. Here, we aimed to investigate the role of ATF6 in a preclinical SAP mouse model and characterize its regulatory mechanism. Methods: Pancreatic tissues of healthy and SAP patients were collected during surgery. Humanized PRSS1 transgenic mice were treated with caerulein to mimic the SAP development, which was crossed to an ATF6 knockout mouse line, and pancreatic tissues from the resulting pups were screened by proteomics. Adenovirus-mediated delivery to the pancreas of SAP mice was used for shRNA-based knockdown or overexpression. The potential functions and mechanisms of ATF6 were clarified by immunofluorescence, immunoelectron microscopy, Western blotting, qRT-PCR, ChIP-qPCR and luciferase reporter assay. Results: Increased expression of ATF6 was associated with elevated apoptosis, ER and mitochondrial disorder in pancreatic tissues from SAP patients and PRSS1 mice. Knockout of ATF6 in SAP mice attenuated acinar injury, apoptosis and ER disorder. AIFM2, known as a p53 target gene, was identified as a downstream regulatory partner of ATF6, whose expression was increased in SAP. Functionally, AIFM2 could reestablish the pathological disorder in SAP tissues in the absence of ATF6. p53 expression was also increased in SAP mice, which was downregulated by ATF6 knockout. p53 knockout significantly suppressed acinar apoptosis and injury in SAP model. Mechanistically, ATF6 promoted AIFM2 transcription by binding to p53 and AIFM2 promoters. Conclusion: These results reveal that ATF6/p53/AIFM2 pathway plays a critical role in acinar apoptosis during SAP progression, highlighting novel therapeutic target molecules for SAP.
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Affiliation(s)
- Jie-Hui Tan
- Division of Hepatobiliopancreatic Surgery, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Rong-Chang Cao
- Division of Hepatobiliopancreatic Surgery, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Lei Zhou
- Division of Hepatobiliopancreatic Surgery, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhi-Tao Zhou
- Department of the Electronic Microscope Room, Central Laboratory, Southern Medical University, Guangzhou, China
| | - Huo-Ji Chen
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Jia Xu
- Department of Pathophysiology, Southern Medical University, Guangzhou, China
| | - Xue-Mei Chen
- Department of Occupational Health and Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yang-Chen Jin
- The First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Jia-Yu Lin
- The First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Jun-Ling Zeng
- Laboratory Animal Research Center of Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Shu-Ji Li
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou, China
| | - Min Luo
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Guo-Dong Hu
- Department of Respiratory and Crit Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiao-Bing Yang
- Division of Nephrology, Nanfang Hospital, Southern Medical University, National Clinical Research Center for Kidney Disease, State Key Laboratory of Organ Failure Research, Guangdong Institute, Guangzhou, China
| | - Jin Jin
- Department of Gynaecology and Obstetrics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Guo-Wei Zhang
- Division of Hepatobiliopancreatic Surgery, Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
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83
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Uremic Sarcopenia: Clinical Evidence and Basic Experimental Approach. Nutrients 2020; 12:nu12061814. [PMID: 32570738 PMCID: PMC7353433 DOI: 10.3390/nu12061814] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/27/2020] [Accepted: 06/16/2020] [Indexed: 12/17/2022] Open
Abstract
Sustained physical activity extends healthy life years while a lower activity due to sarcopenia can reduce them. Sarcopenia is defined as a decrease in skeletal muscle mass and strength due not only to aging, but also from a variety of debilitating chronic illnesses such as cancer and heart failure. Patients with chronic kidney disease (CKD), who tend to be cachexic and in frail health, may develop uremic sarcopenia or uremic myopathy due to an imbalance between muscle protein synthesis and catabolism. Here, we review clinical evidence indicating reduced physical activity as renal function deteriorates and explore evidence-supported therapeutic options focusing on nutrition and physical training. In addition, although sarcopenia is a clinical concept and difficult to recapitulate in basic research, several in vivo approaches have been attempted, such as rodent subtotal nephrectomy representing both renal dysfunction and muscle weakness. This review highlights molecular mechanisms and promising interventions for uremic sarcopenia that were revealed through basic research. Extensive study is still needed to cast light on the many aspects of locomotive organ impairments in CKD and explore the ways that diet and exercise therapies can improve both outcomes and quality of life at every level.
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84
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Nishi H, Nangaku M. Podocyte lipotoxicity in diabetic kidney disease. Kidney Int 2020; 96:809-812. [PMID: 31543147 DOI: 10.1016/j.kint.2019.07.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 07/17/2019] [Indexed: 01/30/2023]
Affiliation(s)
- Hiroshi Nishi
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
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85
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Opazo-Ríos L, Mas S, Marín-Royo G, Mezzano S, Gómez-Guerrero C, Moreno JA, Egido J. Lipotoxicity and Diabetic Nephropathy: Novel Mechanistic Insights and Therapeutic Opportunities. Int J Mol Sci 2020; 21:E2632. [PMID: 32290082 PMCID: PMC7177360 DOI: 10.3390/ijms21072632] [Citation(s) in RCA: 170] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 02/06/2023] Open
Abstract
Lipotoxicity is characterized by the ectopic accumulation of lipids in organs different from adipose tissue. Lipotoxicity is mainly associated with dysfunctional signaling and insulin resistance response in non-adipose tissue such as myocardium, pancreas, skeletal muscle, liver, and kidney. Serum lipid abnormalities and renal ectopic lipid accumulation have been associated with the development of kidney diseases, in particular diabetic nephropathy. Chronic hyperinsulinemia, often seen in type 2 diabetes, plays a crucial role in blood and liver lipid metabolism abnormalities, thus resulting in increased non-esterified fatty acids (NEFA). Excessive lipid accumulation alters cellular homeostasis and activates lipogenic and glycogenic cell-signaling pathways. Recent evidences indicate that both quantity and quality of lipids are involved in renal damage associated to lipotoxicity by activating inflammation, oxidative stress, mitochondrial dysfunction, and cell-death. The pathological effects of lipotoxicity have been observed in renal cells, thus promoting podocyte injury, tubular damage, mesangial proliferation, endothelial activation, and formation of macrophage-derived foam cells. Therefore, this review examines the recent preclinical and clinical research about the potentially harmful effects of lipids in the kidney, metabolic markers associated with these mechanisms, major signaling pathways affected, the causes of excessive lipid accumulation, and the types of lipids involved, as well as offers a comprehensive update of therapeutic strategies targeting lipotoxicity.
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Affiliation(s)
- Lucas Opazo-Ríos
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Sebastián Mas
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Gema Marín-Royo
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Sergio Mezzano
- Laboratorio de Nefrología, Facultad de Medicina, Universidad Austral de Chile, 5090000 Valdivia, Chile;
| | - Carmen Gómez-Guerrero
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Juan Antonio Moreno
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), University of Cordoba, 14004 Cordoba, Spain
- Hospital Universitario Reina Sofía, 14004 Cordoba, Spain
| | - Jesús Egido
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
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86
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Maekawa H, Inagi R. Pathophysiological Role of Organelle Stress/Crosstalk in AKI-to-CKD Transition. Semin Nephrol 2019; 39:581-588. [DOI: 10.1016/j.semnephrol.2019.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Lipotoxicity in Kidney, Heart, and Skeletal Muscle Dysfunction. Nutrients 2019; 11:nu11071664. [PMID: 31330812 PMCID: PMC6682887 DOI: 10.3390/nu11071664] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/01/2019] [Accepted: 07/17/2019] [Indexed: 12/19/2022] Open
Abstract
Dyslipidemia is a common nutritional and metabolic disorder in patients with chronic kidney disease. Accumulating evidence supports the hypothesis that prolonged metabolic imbalance of lipids leads to ectopic fat distribution in the peripheral organs (lipotoxicity), including the kidney, heart, and skeletal muscle, which accelerates peripheral inflammation and afflictions. Thus, lipotoxicity may partly explain progression of renal dysfunction and even extrarenal complications, including renal anemia, heart failure, and sarcopenia. Additionally, endoplasmic reticulum stress activated by the unfolded protein response pathway plays a pivotal role in lipotoxicity by modulating the expression of key enzymes in lipid synthesis and oxidation. Here, we review the molecular mechanisms underlying lipid deposition and resultant tissue damage in the kidney, heart, and skeletal muscle, with the goal of illuminating the nutritional aspects of these pathologies.
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