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Hu J, Tan Y, Chen Y, Mo S, Hekking B, Su J, Pu M, Lu A, Symons JD, Yang T. Role of (Pro)Renin Receptor in Cyclosporin A-Induced Nephropathy. Am J Physiol Renal Physiol 2022; 322:F437-F448. [PMID: 35073210 PMCID: PMC9662808 DOI: 10.1152/ajprenal.00332.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Calcineurin inhibitors (CNIs) such as cyclosporin A (CsA) have been widely used to improve graft survival following solid-organ transplantation. However, the clinical use of CsA is often limited by its nephrotoxicity. The present study tested the hypothesis that activation of (pro)renin receptor (PRR) contributes to CsA-induced nephropathy by activating the renin-angiotensin system (RAS). Renal injury in male Sprague-Dawley rats was induced by a low-salt diet combined with CsA as evidenced by elevated plasma creatinine and BUN levels, decreased creatinine clearance and induced renal inflammation, apoptosis as well as interstitial fibrosis, elevated urinary N-acetyl-β-D-glucosaminidase activity and urinary kidney injury molecular 1 content. Each index of renal injury was attenuated following a 2-wk treatment with a PRR decoy inhibitor PRO20. While CsA rats with kidney injury displayed increased renal sPRR abundance, plasma sPRR, renin activity, Ang II, and heightened urinary total prorenin/renin content; RAS activation was attenuated by PRO20. Exposure of cultured human renal proximal tubular HK-2 cells to CsA induced expression of fibronectin and sPRR production, but the fibrotic response was attenuated by PRO20 and siRNA-mediated PRR knockdown. These findings support the hypothesis that activation of PRR contributes to CsA-induced nephropathy by activating the RAS in rats. Of importance, we provide strong proof of concept that targeting PRR offers a novel therapeutic strategy to limit nephotoxic effects of immunosuppressant drugs.
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Affiliation(s)
- Jiajia Hu
- Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Yandan Tan
- Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Yanting Chen
- Department of Internal Medicine, University of Utah School of Medicine and Veterans Affairs Medical Center, Salt Lake City, Utah, United States
| | - Shiqi Mo
- Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Brittin Hekking
- Department of Internal Medicine, University of Utah School of Medicine and Veterans Affairs Medical Center, Salt Lake City, Utah, United States
| | - Jiahui Su
- Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Min Pu
- Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Aihua Lu
- Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - J. David Symons
- Department of Nutrition and Integrative Physiology; Division of Endocrinology, Metabolism, and Diabetes, Molecular Medicine Program, University of Utah School of Medicine, Salt Lake City, Utah
| | - Tianxin Yang
- Department of Internal Medicine, University of Utah School of Medicine and Veterans Affairs Medical Center, Salt Lake City, Utah, United States
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Justina VD, Giachini FR, Sullivan JC, Webb RC. Toll-Like Receptors Contribute to Sex Differences in Blood Pressure Regulation. J Cardiovasc Pharmacol 2020; 76:255-266. [PMID: 32902942 PMCID: PMC7751064 DOI: 10.1097/fjc.0000000000000869] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Toll-like receptors (TLRs) play an important role in the innate immune system, and recently, they have been shown to be involved in the regulation of blood pressure. The incidence of hypertension is higher in men, and it increases in postmenopausal women. In fact, premenopausal women are protected from cardiovascular disease compared with age-matched men, and it is well established that this protective effect is lost with menopause. However, the molecular mechanisms underlying this protection in women are unknown. Whether or not it could be related to differential activation of the innate immune system remains to be elucidated. This review focuses on (1) the differences between men and women in TLR activation and (2) whether TLR activation may influence the regulation of blood pressure in a sex-dependent manner.
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Affiliation(s)
- Vanessa Dela Justina
- Graduate Program in Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Fernanda R. Giachini
- Graduate Program in Biological Sciences, Federal University of Goiás, Goiânia, Brazil
- Institute of Health Sciences and Health, Universidad Federal De Mato Grosso, Barra Do Garcas, Brazil
| | - Jennifer C. Sullivan
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA
| | - R. Clinton Webb
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA
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3
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Cockfield SM, Wilson S, Campbell PM, Cantarovich M, Gangji A, Houde I, Jevnikar AM, Keough‐Ryan TM, Monroy‐Cuadros F, Nickerson PW, Pâquet MR, Ramesh Prasad GV, Senécal L, Shoker A, Wolff J, Howell J, Schwartz JJ, Rush DN. Comparison of the effects of standard vs low-dose prolonged-release tacrolimus with or without ACEi/ARB on the histology and function of renal allografts. Am J Transplant 2019; 19:1730-1744. [PMID: 30582281 PMCID: PMC6590452 DOI: 10.1111/ajt.15225] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 01/25/2023]
Abstract
Targeting the renin-angiotensin system and optimizing tacrolimus exposure are both postulated to improve outcomes in renal transplant recipients (RTRs) by preventing interstitial fibrosis/tubular atrophy (IF/TA). In this multicenter, prospective, open-label controlled trial, adult de novo RTRs were randomized in a 2 × 2 design to low- vs standard-dose (LOW vs STD) prolonged-release tacrolimus and to angiotensin-converting enzyme inhibitors/angiotensin II receptor 1 blockers (ACEi/ARBs) vs other antihypertensive therapy (OAHT). There were 2 coprimary endpoints: the prevalence of IF/TA at month 6 and at month 24. IF/TA prevalence was similar for LOW vs STD tacrolimus at month 6 (36.8% vs 39.5%; P = .80) and ACEi/ARBs vs OAHT at month 24 (54.8% vs 58.2%; P = .33). IF/TA progression decreased significantly with LOW vs STD tacrolimus at month 24 (mean [SD] change, +0.42 [1.477] vs +1.10 [1.577]; P = .0039). Across the 4 treatment groups, LOW + ACEi/ARB patients exhibited the lowest mean IF/TA change and, compared with LOW + OAHT patients, experienced significantly delayed time to first T cell-mediated rejection. Renal function was stable from month 1 to month 24 in all treatment groups. No unexpected safety findings were detected. Coupled with LOW tacrolimus dosing, ACEi/ARBs appear to reduce IF/TA progression and delay rejection relative to reduced tacrolimus exposure without renin-angiotensin system blockade. ClinicalTrials.gov identifier: NCT00933231.
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Affiliation(s)
| | - Sam Wilson
- Astellas Pharma Global DevelopmentNorthbrookIllinois
| | | | | | - Azim Gangji
- St. Joseph's Healthcare HamiltonHamiltonOntarioCanada
| | | | | | | | | | | | | | | | | | | | | | - John Howell
- Astellas Pharma Global Development, Inc.MarkhamOntarioCanada
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Bomfim GF, Cau SBA, Bruno AS, Fedoce AG, Carneiro FS. Hypertension: a new treatment for an old disease? Targeting the immune system. Br J Pharmacol 2019; 176:2028-2048. [PMID: 29969833 PMCID: PMC6534786 DOI: 10.1111/bph.14436] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/14/2018] [Accepted: 06/24/2018] [Indexed: 12/22/2022] Open
Abstract
Arterial hypertension represents a serious public health problem, being a major cause of morbidity and mortality worldwide. The availability of many antihypertensive therapeutic strategies still fails to adequately treat around 20% of hypertensive patients, who are considered resistant to conventional treatment. In the pathogenesis of hypertension, immune system mechanisms are activated and both the innate and adaptive immune responses play a crucial role. However, what, when and how the immune system is triggered during hypertension development is still largely undefined. In this context, this review highlights scientific advances in the manipulation of the immune system in order to attenuate hypertension and end-organ damage. Here, we discuss the potential use of immunosuppressants and immunomodulators as pharmacological tools to control the activation of the immune system, by non-specific and specific mechanisms, to treat hypertension and improve end-organ damage. Nevertheless, more clinical trials should be performed with these drugs to establish their therapeutic efficacy, safety and risk-benefit ratio in hypertensive conditions. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.
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Affiliation(s)
| | - Stefany Bruno Assis Cau
- Department of Pharmacology, Institute of Biological ScienceFederal University of Minas GeraisBelo HorizonteMGBrazil
| | - Alexandre Santos Bruno
- Department of Pharmacology, Institute of Biological ScienceFederal University of Minas GeraisBelo HorizonteMGBrazil
| | - Aline Garcia Fedoce
- Department of Pharmacology, Ribeirão Preto Medical SchoolUniversity of São PauloSão PauloBrazil
| | - Fernando S Carneiro
- Department of Pharmacology, Ribeirão Preto Medical SchoolUniversity of São PauloSão PauloBrazil
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Zhang J, Diao B, Lin X, Xu J, Tang F. TLR2 and TLR4 mediate an activation of adipose tissue renin-angiotensin system induced by uric acid. Biochimie 2019; 162:125-133. [PMID: 31002842 DOI: 10.1016/j.biochi.2019.04.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 04/12/2019] [Indexed: 02/04/2023]
Abstract
Both hyperuricemia and adipose tissue renin-angiotensin system (RAS) are closely associated with multiple metabolic and cardiovascular diseases. We previously reported that uric acid could upregulate tissue RAS in adipocytes. In the present study, we aimed to reveal the involvement of toll-like receptors (TLRs) in uric acid-induced RAS activation in adipose tissue. A hyperuricemia rat model fed with a high-fructose diet and rat primary adipocytes were used in this study. Here, we inhibited TLR2 and TLR4 expression in adipose tissue and cultured adipocytes using small interfering RNA (siRNA). We found that high fructose-fed rats had hyperuricemia, higher body weight and greater adipose tissue content. We also found that hyperuricemia rats had raising blood pressure, higher expression levels of inflammatory cytokines and RAS components in adipose tissue, which could be prevented by TLR2/4-siRNA infection. In vitro study, uric acid caused a dose- and time-dependent increase in the mRNA expression of TLR2 and TLR4 in rat adipocytes. Uric acid could increase inflammatory cytokines and upregulate tissue RAS in rat adipocytes, which were both blocked with TLR2/4-siRNA infection. TNF-α and IL-6 could also result in an activation of tissue RAS expression in adipocytes. In conclusion, TLR2/4 mediated adipose inflammation plays a key role in RAS activation induced by uric acid in adipose tissue.
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Affiliation(s)
- Junxia Zhang
- Department of Endocrinology, Central War Zone General Hospital of the Chinese People's Liberation Army, Wuhan, China.
| | - Bo Diao
- Department of Clinical Experiment, Central War Zone General Hospital of the Chinese People's Liberation Army, Wuhan, China
| | - Xue Lin
- Department of Endocrinology, Central War Zone General Hospital of the Chinese People's Liberation Army, Wuhan, China
| | - Jinxiu Xu
- Department of Endocrinology, Central War Zone General Hospital of the Chinese People's Liberation Army, Wuhan, China
| | - Feng Tang
- Department of Endocrinology, Central War Zone General Hospital of the Chinese People's Liberation Army, Wuhan, China
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6
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Elkahloun AG, Rodriguez Y, Alaiyed S, Wenzel E, Saavedra JM. Telmisartan Protects a Microglia Cell Line from LPS Injury Beyond AT1 Receptor Blockade or PPARγ Activation. Mol Neurobiol 2018; 56:3193-3210. [PMID: 30105672 DOI: 10.1007/s12035-018-1300-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/02/2018] [Indexed: 01/12/2023]
Abstract
The Angiotensin II Receptor Blocker (ARB) Telmisartan reduces inflammation through Angiotensin II AT1 receptor blockade and peroxisome proliferator-activated receptor gamma (PPARγ) activation. However, in a mouse microglia-like BV2 cell line, imitating primary microglia responses with high fidelity and devoid of AT1 receptor gene expression or PPARγ activation, Telmisartan reduced gene expression of pro-injury factors, enhanced that of anti-inflammatory genes, and prevented LPS-induced increase in inflammatory markers. Using global gene expression profiling and pathways analysis, we revealed that Telmisartan normalized the expression of hundreds of genes upregulated by LPS and linked with inflammation, apoptosis and neurodegenerative disorders, while downregulating the expression of genes associated with oncological, neurodegenerative and viral diseases. The PPARγ full agonist Pioglitazone had no neuroprotective effects. Surprisingly, the PPARγ antagonists GW9662 and T0070907 were neuroprotective and enhanced Telmisartan effects. GW9226 alone significantly reduced LPS toxic effects and enhanced Telmisartan neuroprotection, including downregulation of pro-inflammatory TLR2 gene expression. Telmisartan and GW9662 effects on LPS injury negatively correlated with pro-inflammatory factors and upstream regulators, including TLR2, and positively with known neuroprotective factors and upstream regulators. Gene Set Enrichment Analysis (GSEA) of the Telmisartan and GW9662 data revealed negative correlations with sets of genes associated with neurodegenerative and metabolic disorders and toxic treatments in cultured systems, while demonstrating positive correlations with gene sets associated with neuroprotection and kinase inhibition. Our results strongly suggest that novel neuroprotective effects of Telmisartan and GW9662, beyond AT1 receptor blockade or PPARγ activation, include downregulation of the TLR2 signaling pathway, findings that may have translational relevance.
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Affiliation(s)
- Abdel G Elkahloun
- Microarray Core, Cancer Genetics and Comparative Genomics Branch, National Human Genome Research Institute, National Institutes of Health, 50 South Dr, MSC 4435, Bethesda, MD, 20892-4435, USA
| | - Yara Rodriguez
- Laboratory of Neuroprotection, Department of Pharmacology and Physiology, Georgetown University Medical Center, SE402 Med/Dent, 3900 Reservoir Road, Washington, DC, 20057, USA
| | - Seham Alaiyed
- Laboratory of Neuroprotection, Department of Pharmacology and Physiology, Georgetown University Medical Center, SE402 Med/Dent, 3900 Reservoir Road, Washington, DC, 20057, USA
| | - Erin Wenzel
- Laboratory of Neuroprotection, Department of Pharmacology and Physiology, Georgetown University Medical Center, SE402 Med/Dent, 3900 Reservoir Road, Washington, DC, 20057, USA
| | - Juan M Saavedra
- Laboratory of Neuroprotection, Department of Pharmacology and Physiology, Georgetown University Medical Center, SE402 Med/Dent, 3900 Reservoir Road, Washington, DC, 20057, USA.
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7
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Bomfim GF, Rodrigues FL, Carneiro FS. Are the innate and adaptive immune systems setting hypertension on fire? Pharmacol Res 2017; 117:377-393. [PMID: 28093357 DOI: 10.1016/j.phrs.2017.01.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 12/06/2016] [Accepted: 01/09/2017] [Indexed: 02/08/2023]
Abstract
Hypertension is the most common chronic cardiovascular disease and is associated with several pathological states, being an important cause of morbidity and mortality around the world. Low-grade inflammation plays a key role in hypertension and the innate and adaptive immune systems seem to contribute to hypertension development and maintenance. Hypertension is associated with vascular inflammation, increased vascular cytokines levels and infiltration of immune cells in the vasculature, kidneys and heart. However, the mechanisms that trigger inflammation and immune system activation in hypertension are completely unknown. Cells from the innate immune system express pattern recognition receptors (PRR), which detect conserved pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) that induce innate effector mechanisms to produce endogenous signals, such as inflammatory cytokines and chemokines, to alert the host about danger. Additionally, antigen-presenting cells (APC) act as sentinels that are activated by PAMPs and DAMPs to sense the presence of the antigen/neoantigen, which ensues the adaptive immune system activation. In this context, different lymphocyte types are activated and contribute to inflammation and end-organ damage in hypertension. This review will focus on experimental and clinical evidence demonstrating the contribution of the innate and adaptive immune systems to the development of hypertension.
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Affiliation(s)
- Gisele F Bomfim
- Institute of Health Sciences, Federal University of Mato Grosso, Sinop, MT, Brazil
| | - Fernanda Luciano Rodrigues
- Department of Physiology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Fernando S Carneiro
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av Bandeirantes, 3900, 14049-900 Ribeirao Preto, SP, Brazil.
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8
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Diehl R, Ferrara F, Müller C, Dreyer AY, McLeod DD, Fricke S, Boltze J. Immunosuppression for in vivo research: state-of-the-art protocols and experimental approaches. Cell Mol Immunol 2016; 14:146-179. [PMID: 27721455 PMCID: PMC5301156 DOI: 10.1038/cmi.2016.39] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 05/30/2016] [Accepted: 05/30/2016] [Indexed: 02/06/2023] Open
Abstract
Almost every experimental treatment strategy using non-autologous cell, tissue or organ transplantation is tested in small and large animal models before clinical translation. Because these strategies require immunosuppression in most cases, immunosuppressive protocols are a key element in transplantation experiments. However, standard immunosuppressive protocols are often applied without detailed knowledge regarding their efficacy within the particular experimental setting and in the chosen model species. Optimization of such protocols is pertinent to the translation of experimental results to human patients and thus warrants further investigation. This review summarizes current knowledge regarding immunosuppressive drug classes as well as their dosages and application regimens with consideration of species-specific drug metabolization and side effects. It also summarizes contemporary knowledge of novel immunomodulatory strategies, such as the use of mesenchymal stem cells or antibodies. Thus, this review is intended to serve as a state-of-the-art compendium for researchers to refine applied experimental immunosuppression and immunomodulation strategies to enhance the predictive value of preclinical transplantation studies.
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Affiliation(s)
- Rita Diehl
- Fraunhofer-Institute for Cell Therapy and Immunology, Leipzig 04103, Germany
| | - Fabienne Ferrara
- Fraunhofer-Institute for Cell Therapy and Immunology, Leipzig 04103, Germany.,Institute of Vegetative Physiology, Charite University Medicine and Center for Cardiovascular Research, Berlin 10115, Germany
| | - Claudia Müller
- Fraunhofer-Institute for Cell Therapy and Immunology, Leipzig 04103, Germany
| | - Antje Y Dreyer
- Fraunhofer-Institute for Cell Therapy and Immunology, Leipzig 04103, Germany
| | | | - Stephan Fricke
- Fraunhofer-Institute for Cell Therapy and Immunology, Leipzig 04103, Germany
| | - Johannes Boltze
- Fraunhofer-Institute for Cell Therapy and Immunology, Leipzig 04103, Germany.,Fraunhofer Research Institution for Marine Biotechnology and Institute for Medical and Marine Biotechnology, University of Lübeck, Lübeck 23562, Germany
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9
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Bletilla striata polysaccharide inhibits angiotensin II-induced ROS and inflammation via NOX4 and TLR2 pathways. Int J Biol Macromol 2016; 89:376-88. [DOI: 10.1016/j.ijbiomac.2016.05.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 04/26/2016] [Accepted: 05/01/2016] [Indexed: 11/24/2022]
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10
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Chung S, Jeong JY, Chang YK, Choi DE, Na KR, Lim BJ, Lee KW. Concomitant inhibition of renin angiotensin system and Toll-like receptor 2 attenuates renal injury in unilateral ureteral obstructed mice. Korean J Intern Med 2016; 31:323-34. [PMID: 26932402 PMCID: PMC4773720 DOI: 10.3904/kjim.2015.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 03/20/2015] [Accepted: 06/02/2015] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND/AIMS There has been controversy about the role of Toll-like receptor 2 (TLR2) in renal injury following ureteric obstruction. Although inhibition of the renin angiotensin system (RAS) reduces TLR2 expression in mice, the exact relationship between TLR2 and RAS is not known. The aim of this study was to determine whether the RAS modulates TLR2. METHODS We used 8-week-old male wild type (WT) and TLR2-knockout (KO) mice on a C57Bl/6 background. Unilateral ureteral obstruction (UUO) was induced by complete ligation of the left ureter. Angiotensin (Ang) II (1,000 ng/kg/min) and the direct renin inhibitor aliskiren (25 mg/kg/day) were administrated to mice using an osmotic minipump. Molecular and histologic evaluations were performed. RESULTS Ang II infusion increased mRNA expression of TLR2 in WT mouse kidneys (p < 0.05). The expression of renin mRNA in TLR2-KO UUO kidneys was significantly higher than that in WT UUO kidneys (p < 0.05). There were no differences in tissue injury score or mRNA expression of monocyte chemotactic protein 1 (MCP-1), osteopontin (OPN), or transforming growth factor β (TGF-β) between TLR2-KO UUO and WT UUO kidneys. However, aliskiren decreased the tissue injury score and mRNA expression of TLR2, MCP-1, OPN, and TGF-β in WT UUO kidneys (p < 0.05). Aliskiren-treated TLR2-KO UUO kidneys showed less kidney injury than aliskiren-treated WT UUO kidneys. CONCLUSIONS TLR2 deletion induced activation of the RAS in UUO kidneys. Moreover, inhibition of both RAS and TLR2 had an additive ameliorative effect on UUO injury of the kidney.
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Affiliation(s)
- Sarah Chung
- Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea
| | - Jin Young Jeong
- Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea
| | - Yoon Kyung Chang
- Department of Internal Medicine, College of Medicine, Daejeon St. Mary’s Hospital, The Catholic University of Korea, Daejeon, Korea
| | - Dae Eun Choi
- Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea
| | - Ki Ryang Na
- Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea
| | - Beom Jin Lim
- Department of Pathology, Yonsei University College of Medicine, Seoul, Korea
| | - Kang Wook Lee
- Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea
- Correspondence to Kang Wook Lee Department of Internal Medicine, Chungnam National University Hospital, 282 Munhwa-ro, Junggu, Daejeon 35015, Korea Tel: +82-42-280-7246 Fax: +82-42-280-7995 E-mail:
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11
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Park HS, Kim EN, Kim MY, Lim JH, Kim HW, Park CW, Yang CW, Jin DC, Choi BS. The protective effect of neutralizing high-mobility group box1 against chronic cyclosporine nephrotoxicity in mice. Transpl Immunol 2015; 34:42-9. [PMID: 26603313 DOI: 10.1016/j.trim.2015.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 11/11/2015] [Accepted: 11/17/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND High-mobility group box1 (HMGB1) is known to be involved in innate immune response through interaction with receptor for advanced glycation end products (RAGE) and toll-like receptors (TLRs), besides its proper role within the nucleus. Immunological pathways, including TLR signaling, are also involved in chronic cyclosporine (CsA) nephrotoxicity. This study was designed to determine whether neutralizing HMGB1 prevents chronic CsA nephrotoxicity. METHODS Chronic CsA nephrotoxicity was induced by CsA subcutaneous injection daily for 4weeks under salt-depletion in mice. Anti-HMGB1 neutralizing antibody for HMGB1 blockade (600mcg/mouse) was administered weekly to mice in the anti-HMGB1 treatment group. The effects of HMGB1 neutralization were evaluated in terms of renal function as well as histological and immunopathological examination. RESULTS Anti-HMGB1 administration prevented the increases in serum creatinine and 24h albuminuria and the decrease in creatinine clearance associated with CsA treatment. Increased tubulointerstitial fibrosis and transforming growth factor (TGF)-β immunohistochemical staining associated with CsA treatment were also prevented by anti-HMGB1 administration. Anti-HMGB1 administration prevented the activation of the TLR4 signaling pathway, which resulted in the reduction of nuclear factor kappa B (NF-κB) expression. In cultured tubular cells, anti-HMGB1 pretreatment also prevented the increases in fibronectin and collagen IV levels associated with CsA treatment. CONCLUSIONS Neutralizing HMGB1 with an anti-HMGB1 antibody ameliorated chronic CsA nephrotoxicity via inhibition of the TLR4 signaling pathway. Our study suggests that HMGB1 blockade can be beneficial for increasing allograft survival in renal transplant recipients by protecting against calcineurin inhibitor-induced nephrotoxicity.
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Affiliation(s)
- Hoon Suk Park
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Eun Nim Kim
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Min Young Kim
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ji Hee Lim
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Hyung Wook Kim
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Cheol Whee Park
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Chul Woo Yang
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Dong Chan Jin
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Bum Soon Choi
- Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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12
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Silva-Filho JL, Souza MC, Henriques MG, Morrot A, Savino W, Caruso-Neves C, Pinheiro AAS. Renin-angiotensin system contributes to naive T-cell migration in vivo. Arch Biochem Biophys 2015; 573:1-13. [PMID: 25752953 DOI: 10.1016/j.abb.2015.02.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/04/2015] [Accepted: 02/28/2015] [Indexed: 01/11/2023]
Abstract
Angiotensin II (Ang II) plays an important role in the regulation of the T-cell response during inflammation. However, the cellular mechanisms underlying the regulation of lymphocytes under physiologic conditions have not yet been studied. Here, we tested the influence of Ang II on T-cell migration using T cells from BALB/c mice. The results obtained in vivo showed that when Ang II production or the AT1 receptor were blocked, T-cell counts were enhanced in blood but decreased in the spleen. The significance of these effects was confirmed by observing that these cells migrate, through fibronectin to Ang II via the AT1 receptor. We also observed a gradient of Ang II from peripheral blood to the spleen, which explains its chemotactic effect on this organ. The following cellular mechanisms were identified to mediate the Ang II effect: upregulation of the chemokine receptor CCR9; upregulation of the adhesion molecule CD62L; increased production of the chemokines CCL19 and CCL25 in the spleen. These results indicate that the higher levels of Ang II in the spleen and AT1 receptor activation contribute to migration of naive T cells to the spleen, which expands our understanding on how the Ang II/AT1 receptor axis contributes to adaptive immunity.
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Affiliation(s)
- J L Silva-Filho
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - M C Souza
- Instituto de Tecnologia em Fármacos, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - M G Henriques
- Instituto de Tecnologia em Fármacos, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - A Morrot
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - W Savino
- Departamento de Imunologia, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - C Caruso-Neves
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia e Bioimagem, Conselho Nacional de Desenvolvimento Científico e Tecnológico/MCT, Brazil
| | - A A S Pinheiro
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Instituto Nacional para Pesquisa Translacional em Saúde e Ambiente na Região Amazônica, Conselho Nacional de Desenvolvimento Científico e Tecnológico/MCT, Brazil.
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Rogers NM, Ferenbach DA, Isenberg JS, Thomson AW, Hughes J. Dendritic cells and macrophages in the kidney: a spectrum of good and evil. Nat Rev Nephrol 2014; 10:625-43. [PMID: 25266210 PMCID: PMC4922410 DOI: 10.1038/nrneph.2014.170] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Renal dendritic cells (DCs) and macrophages represent a constitutive, extensive and contiguous network of innate immune cells that provide sentinel and immune-intelligence activity; they induce and regulate inflammatory responses to freely filtered antigenic material and protect the kidney from infection. Tissue-resident or infiltrating DCs and macrophages are key factors in the initiation and propagation of renal disease, as well as essential contributors to subsequent tissue regeneration, regardless of the aetiological and pathogenetic mechanisms. The identification, and functional and phenotypic distinction of these cell types is complex and incompletely understood, and the same is true of their interplay and relationships with effector and regulatory cells of the adaptive immune system. In this Review, we discuss the common and distinct characteristics of DCs and macrophages, as well as key advances that have identified the renal-specific functions of these important phagocytic, antigen-presenting cells, and their roles in potentiating or mitigating intrinsic kidney disease. We also identify remaining issues that are of priority for further investigation, and highlight the prospects for translational and therapeutic application of the knowledge acquired.
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Affiliation(s)
- Natasha M Rogers
- Vascular Medicine Institute and Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, W1544 Biomedical Science Tower, 200 Lothrop Street, Pittsburgh, PA 15261, USA
| | - David A Ferenbach
- MRC Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Jeffrey S Isenberg
- Vascular Medicine Institute and Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, W1544 Biomedical Science Tower, 200 Lothrop Street, Pittsburgh, PA 15261, USA
| | - Angus W Thomson
- Vascular Medicine Institute and Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, W1544 Biomedical Science Tower, 200 Lothrop Street, Pittsburgh, PA 15261, USA
| | - Jeremy Hughes
- MRC Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
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Wu H, Cheng XW, Hu L, Hao CN, Hayashi M, Takeshita K, Hamrah MS, Shi GP, Kuzuya M, Murohara T. Renin inhibition reduces atherosclerotic plaque neovessel formation and regresses advanced atherosclerotic plaques. Atherosclerosis 2014; 237:739-47. [PMID: 25463114 DOI: 10.1016/j.atherosclerosis.2014.10.098] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 10/20/2014] [Accepted: 10/27/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The interaction between the renin-angiotensin system and toll-like receptors (TLRs) in the pathogenesis of advanced atherosclerotic plaques is not well understood. We studied the effects of the renin inhibitor aliskiren on the progression of advanced atherosclerotic plaque in apolipoprotein E-deficient (ApoE(-/-)) mice with a special focus on plaque neovessel formation. METHODS AND RESULTS Four-wk-old ApoE(-/-) mice were fed a high-fat diet for 8 wks, and the mice were randomly assigned to one of three groups and administered a vehicle, hydralazine, or aliskiren for an additional 12 wks. Aliskiren reduced the atherosclerotic plaque area and plaque neovessel density. It increased the plaque collagen and elastin contents, and reduced plasma angiotensin II levels and plaque macrophage infiltration and cathepsin S (CatS) protein. Aliskiren also decreased the levels of AT1R, gp91phox, TLR2, monocyte chemotactic protein-1, and CatS mRNAs in the aortic roots. Hydralazine had no beneficial vascular effects, although its administration resulted in the same degree of blood pressure reduction as aliskiren. CatS deficiency mimicked the aliskiren-mediated vasculoprotective effect in the ApoE(-/-) mice, but aliskiren showed no further benefits in ApoE(-/-) CatS(-/-) mice. In vitro, TLR2 silencing reduced CatS expression induced by angiotensin II. Moreover, aliskiren or the inhibition of CatS impaired the endothelial cell angiogenic action in vitro or/and ex vivo. CONCLUSION Renin inhibition appears to inhibit advanced plaque neovessel formation in ApoE(-/-) mice and to decrease the vascular inflammatory action and extracellular matrix degradation, partly by reducing AT1R/TLR2-mediated CatS activation and activity, thus regressing advanced atherosclerosis.
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Affiliation(s)
- Hongxian Wu
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Xian Wu Cheng
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan; Department of Community Healthcare & Geriatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan; Department of Cardiology, Yanbian University Hospital, Yanji, China.
| | - Lina Hu
- Department of Community Healthcare & Geriatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Chang-Ning Hao
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Mutsuharu Hayashi
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kyosuke Takeshita
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | | | - Guo-Ping Shi
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States
| | - Masafumi Kuzuya
- Department of Community Healthcare & Geriatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Toyoaki Murohara
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
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15
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Li Y, Wu Y, Zhang C, Li P, Cui W, Hao J, Ma X, Yin Z, Du J. γδT Cell-derived interleukin-17A via an interleukin-1β-dependent mechanism mediates cardiac injury and fibrosis in hypertension. Hypertension 2014; 64:305-14. [PMID: 24866139 DOI: 10.1161/hypertensionaha.113.02604] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Inflammation is implicated in the initiation of hypertension and end-organ injury. Interleukin-17A (IL-17A) is a key pathogenic factor in a variety of inflammatory diseases and hypertension. However, the mechanisms underlying IL-17A production, and its role in mediating inflammation and early cardiovascular injury in hypertensive heart, remain unknown. Angiotensin II (Ang II) infusion increased cardiac IL-17A mRNA expression and IL-17A+CD3+ cell infiltration in a time-dependent manner. IL-17A in the hypertensive heart was derived mostly from infiltrating γδT cells rather than from CD4 T cells. Genetic knockdown of γδT cells or specific anti-γδT antibody abolished IL-17A production in Ang II–infused heart. Moreover, monocyte-secreted IL-1β, not cardiac fibroblast–secreted IL-6 or transforming growth factor-β, was required for IL-17A production from γδT cell. IL-17A accelerated differentiation of myofibroblast through promoting IL-6 production from cardiac fibroblast. Finally, inflammatory cell infiltration, proinflammatory or profibrotic cytokine expression, and fibrotic lesion induced by Ang II were attenuated in IL-17A–deficient mice. Moreover, the deletion of γδT cell was protected from Ang II–induced cardiac injury. Thus, a triangular positive feedback loop exists among monocytic-secreted IL-1β, γδT-cell–derived IL-17A, and cardiac fibroblast–produced IL-6, which triggers the cardiac injury in hypertension.
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16
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Abstract
Hypertension and associated inflammatory processes that accelerate cardiovascular damage are regulated by the innate immune system. Toll-like receptors (TLR) are major components of the innate immune system that recognize endogenous damage-associated molecular patterns to activate prominent inflammatory signaling including activation of nuclear factor-κB (NF-κB). However, the role of TLR in the etiology of hypertension is not well understood. TLR signaling is dependent on adaptor proteins that, along with the TLR expression patterns, confer specificity of the inflammatory response and its pathological targets. Here we review the conceptual framework of how TLR and their adaptor proteins may differentially affect hypertension and cardiac hypertrophy by different stimuli.
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Affiliation(s)
- Madhu V Singh
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - François M Abboud
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa
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17
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Cole JE, Mitra AT, Monaco C. Treating atherosclerosis: the potential of Toll-like receptors as therapeutic targets. Expert Rev Cardiovasc Ther 2014; 8:1619-35. [DOI: 10.1586/erc.10.149] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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18
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Huang D, Lu H, Liu H, Yao K, Sun A, Zou Y, Ge J. Losartan attenuates human monocyte-derived dendritic cell immune maturation via downregulation of lectin-like oxidized low-density lipoprotein receptor-1. J Cardiovasc Pharmacol 2012; 60:133-9. [PMID: 22549450 DOI: 10.1097/fjc.0b013e318258f336] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The angiotensin II receptor-1 blockers have generally been shown to have antiatherogenic effects, and dendritic cells (DCs) are the most efficient antigen presenting cells that play an active role in the development of atherosclerosis through inflammatory-immune responses. Here, we tested the hypothesis that the antiatherogenic effect of losartan, the first angiotensin II receptor-1 blockers, might partly be mediated by attenuating DCs maturation. In this study, we showed that oxidized low-density lipoprotein (oxLDL) and angiotensin II (Ang II) could induce the maturation of human monocyte-derived DCs, stimulate CD83, HLA-DR expressions and IL-12, interferon-gamma secretions and increase the capacity of DCs to stimulate T-cell proliferation, which were suppressed by losartan. OxLDL could promote the autocrine secretion of Ang II by DCs and upregulate the expressions of 3 scavenger receptors SR-A, CD36, and LOX-1. Losartan reduced oxLDL-induced LOX-1 expression but not SR-A and CD36 expressions. Ang II could only upregulate the LOX-1 expression, which was reduced by losartan. OxLDL- and Ang II-induced upregulation of CD83 and secretion of IL-12 were all attenuated by LOX-1 neutralizing antibody. In conclusion, losartan could attenuate the oxLDL- and Ang II-induced immune maturation of human monocyte-derived DCs partly through downregulation of the LOX-1 expression.
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Affiliation(s)
- Dong Huang
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
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19
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Yoon HE, Ghee JY, Piao S, Song JH, Han DH, Kim S, Ohashi N, Kobori H, Kuro-o M, Yang CW. Angiotensin II blockade upregulates the expression of Klotho, the anti-ageing gene, in an experimental model of chronic cyclosporine nephropathy. Nephrol Dial Transplant 2010; 26:800-13. [PMID: 20813770 DOI: 10.1093/ndt/gfq537] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The Klotho gene plays a role in suppressing ageing-related disorders. It is suggested that activation of renin-angiotensin system (RAS) or oxidative stress suppresses Klotho in the kidney. This study evaluated the association between Klotho expression and RAS in cyclosporine (CsA)-induced renal injury. METHODS Chronic CsA nephropathy was induced by administering CsA (30 mg/kg) to mice on a low-salt diet (LSD) for 4 weeks. A normal-salt diet (NSD) was used as the control. Reverse transcription-polymerase chain reaction, western blot and immunohistochemistry were performed for Klotho and intrarenal RAS activity was measured using immunohistochemistry for angiotensinogen and renin. Oxidative stress was measured with urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG). RESULTS CsA treatment decreased Klotho mRNA and protein in mouse kidney in a dose-dependent and time-dependent manner, but a concurrent treatment with losartan, an angiotensin II type 1 (AT1) receptor blocker, reversed the decrease in Klotho expression with histological improvement. This finding was more marked in the LSD than the NSD. Klotho expression was correlated with angiotensinogen and renin expression, tubulointerstitial fibrosis score and urinary 8-OHdG excretion. CONCLUSIONS Angiotensin II may play a pivotal role in regulating Klotho expression in CsA-induced renal injury. AT1 receptor blocker may inhibit the ageing process by decreasing oxidative stress caused by CsA.
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Affiliation(s)
- Hye Eun Yoon
- Division of Nephrology, Department of Internal Medicine, Incheon St Mary’s Hospital, College of Medicine, The Catholic University of Korea, Incheon, South Korea
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20
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Good DW, George T, Watts BA. Toll-like receptor 2 mediates inhibition of HCO(3)(-) absorption by bacterial lipoprotein in medullary thick ascending limb. Am J Physiol Renal Physiol 2010; 299:F536-44. [PMID: 20554644 DOI: 10.1152/ajprenal.00108.2010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bacterial infection and sepsis are associated with renal tubule dysfunction and dysregulation of systemic electrolyte balance but the underlying mechanisms are incompletely understood. Recently, we demonstrated that HCO(3)(-) absorption by the medullary thick ascending limb (MTAL) is inhibited by gram-negative bacterial LPS through activation of Toll-like receptor 4 (TLR4). Here, we examined whether MTAL transport is altered by activation of TLR2, the receptor predominantly responsible for recognizing gram-positive bacteria. Confocal immunofluorescence showed expression of TLR2 in the basolateral membrane domain of rat and mouse MTALs. The functional role of TLR2 was examined in perfused MTALs using Pam(3)CSK(4), a bacterial lipoprotein analog that specifically activates TLR2. Adding Pam(3)CSK(4) to the bath decreased HCO(3)(-) absorption by 25%. The inhibition by Pam(3)CSK(4) was eliminated in MTALs from TLR2(-/-) mice. HCO(3)(-) absorption was also inhibited by the TLR2 agonists lipoteichoic acid and peptidoglycan, two cell wall components of gram-positive bacteria. The MEK/ERK inhibitor U0126 eliminated inhibition of HCO(3)(-) absorption by bath LPS but had no effect on inhibition by Pam(3)CSK(4). The inhibition by Pam(3)CSK(4) was eliminated by the protein kinase C inhibitors chelerythrine Cl and bisindolylmaleimide. Moreover, the inhibition by Pam(3)CSK(4), lipoteichoic acid, and peptidoglycan was additive to inhibition by LPS. Thus, agonists of basolateral TLR2 and TLR4 inhibit HCO(3)(-) absorption independently through distinct signaling pathways. We conclude that bacterial components act directly through TLRs to modify the transport function of renal tubules. During polymicrobial sepsis, gram-positive bacterial molecules acting through TLR2 and gram-negative LPS acting through TLR4 can function through parallel signaling pathways to impair MTAL transport. The inhibition of luminal acidification may impair the ability of the kidneys to correct systemic acidosis that contributes to sepsis pathogenesis.
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Affiliation(s)
- David W Good
- Department of Internal Medicine, The University of Texas Medical Branch, Galveston, 77555-0562, USA.
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21
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Arslan F, Keogh B, McGuirk P, Parker AE. TLR2 and TLR4 in ischemia reperfusion injury. Mediators Inflamm 2010; 2010:704202. [PMID: 20628516 PMCID: PMC2902053 DOI: 10.1155/2010/704202] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Accepted: 04/07/2010] [Indexed: 12/15/2022] Open
Abstract
Ischemia reperfusion (I/R) injury refers to the tissue damage which occurs when blood supply returns to tissue after a period of ischemia and is associated with trauma, stroke, myocardial infarction, and solid organ transplantation. Although the cause of this injury is multifactorial, increasing experimental evidence suggests an important role for the innate immune system in initiating the inflammatory cascade leading to detrimental/deleterious changes. The Toll-like Receptors (TLRs) play a central role in innate immunity recognising both pathogen- and damage-associated molecular patterns and have been implicated in a range of inflammatory and autoimmune diseases. In this paper, we summarise the current state of knowledge linking TLR2 and TLR4 to I/R injury, including recent studies which demonstrate that therapeutic inhibition of TLR2 has beneficial effects on I/R injury in a murine model of myocardial infarction.
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Affiliation(s)
- F. Arslan
- Laboratory of Experimental Cardiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - B. Keogh
- Opsona Therapeutics Ltd., Institute of Molecular Medicine, Trinity Centre for Health Sciences, St. James' Hospital, Dublin 8, Ireland
| | - P. McGuirk
- Opsona Therapeutics Ltd., Institute of Molecular Medicine, Trinity Centre for Health Sciences, St. James' Hospital, Dublin 8, Ireland
| | - A. E. Parker
- Opsona Therapeutics Ltd., Institute of Molecular Medicine, Trinity Centre for Health Sciences, St. James' Hospital, Dublin 8, Ireland
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22
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Kuwahata S, Fujita S, Orihara K, Hamasaki S, Oba R, Hirai H, Nagata K, Ishida S, Kataoka T, Oketani N, Ichiki H, Iriki Y, Saihara K, Okui H, Ninomiya Y, Tei C. High expression level of Toll-like receptor 2 on monocytes is an important risk factor for arteriosclerotic disease. Atherosclerosis 2010; 209:248-54. [DOI: 10.1016/j.atherosclerosis.2009.08.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 08/07/2009] [Accepted: 08/24/2009] [Indexed: 01/04/2023]
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Abstract
Toll-like receptors (TLRs) have a key role in innate immunity. These receptors recognize both pathogen-associated molecular patterns and molecules that are released from damaged tissue. TLRs mediate signal transduction pathways through the activation of transcription factors that regulate the expression of proinflammatory cytokines and chemokines and are required for the development of adaptive immune responses. TLRs might have an important role in the pathogenesis of renal diseases: their exaggerated activation is associated with ischemic kidney damage, acute kidney injury, end-stage renal failure, acute tubulointerstitial nephritis, acute renal transplant rejection and delayed allograft function. As the results of previous studies concerning the role of TLRs in renal diseases are conflicting, further work is needed to determine the exact role of these receptors and to evaluate strategies to prevent TLR-mediated local inflammation. This Review discusses the evidence supporting a role for TLRs in contrasting bacterial infections and in causing or aggravating renal conditions when TLR activation leads to a harmful inflammatory response.
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Abstract
Despite improvements in immunosuppressive therapy, long-term allograft survival after kidney transplantation remains as low as 50%. Chronic allograft nephropathy (CAN) is a major cause of late graft loss in renal transplant recipients. The histopathologic signs of CAN-interstitial fibrosis, tubular atrophy, glomerulopathy and vasculopathy-are nonspecific; therefore, the 2007 Banff classification dispensed with the term CAN in favor of 'interstitial fibrosis and tubular atrophy without evidence of any specific etiology'. In this Review, however, the term CAN is used to describe a clinical syndrome that is characterized by progressive decline in renal function from 3 months after transplantation, accompanied by the development of proteinuria and hypertension. The pathogenesis of CAN is complex and incompletely understood, and involves several immunological and non-immunological factors. We discuss the contributory roles of acute rejection, donor age, anti-human-leukocyte-antigen antibodies, calcineurin inhibitor nephrotoxic effects, viral infection, hypertension and hyperlipidemia. The prevention and treatment of CAN needs multidisciplinary strategies. Early detection by means of protocol biopsy and calculation of glomerular filtration rate is the first step, followed by management of modifiable risk factors.
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Abstract
Cyclosporine (CsA) has improved patient and graft survival rates following solid-organ transplantation and has shown significant clinical benefits in the management of autoimmune diseases. However, the clinical use of CsA is often limited by acute or chronic nephropathy, which remains a major problem. Acute nephropathy depends on the dosage of CsA and appears to be caused by a reduction in renal blood flow related to afferent arteriolar vasoconstriction. However, the mechanisms underlying chronic CsA nephropathy are not completely understood. Activation of the intrarenal renin-angiotensin system (RAS), increased release of endothelin-1, dysregulation of nitric oxide (NO) and NO synthase, up-regulation of transforming growth factor-beta1 (TGF-beta1), inappropriate apoptosis, stimulation of inflammatory mediators, enhanced innate immunity, endoplasmic reticulum stress, and autophagy have all been implicated in the pathogenesis of chronic CsA nephropathy. Reducing the CsA dosage or using other renoprotective drugs (angiotensin II receptor antagonist, mycophenolate mofetil, and statins, etc.) may ameliorate chronic CsA-induced renal injury. This review discusses old and new concepts in CsA nephropathy and preventive strategies for this clinical dilemma.
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Affiliation(s)
- Hye Eun Yoon
- Division of Nephrology, Transplantation research center, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea
| | - Chul Woo Yang
- Division of Nephrology, Transplantation research center, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea
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The role of infection in the development of non-valvular atrial fibrillation: up-regulation of Toll-like receptor 2 expression levels on monocytes. J Cardiol 2008; 53:127-35. [PMID: 19167648 DOI: 10.1016/j.jjcc.2008.09.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 09/25/2008] [Accepted: 09/30/2008] [Indexed: 01/20/2023]
Abstract
Many studies have suggested that inflammation may participate in the pathogenesis of non-valvular atrial fibrillation (AF). However, it has been unknown by exposure to what the inflammation is caused. Recently, we reported that Toll-like receptor 2 (TLR2) level on monocytes was significantly up-regulated in viral and bacterial infections, but not in non-infectious inflammatory states. Our purpose was to test the hypothesis that expression of TLR2 levels may be up-regulated in patients with non-valvular AF. A total of 48 consecutive patients with non-valvular AF who were hospitalized for catheter ablation were enrolled in this study. TLR2 levels were assayed by using flow-cytometric analysis and compared with volunteers in sinus rhythm (control group, n = 24). Additionally, C-reactive protein (CRP) and interleukin-6 (IL-6) levels were assayed, and the left atrial volume indexes (LAVI) in the non-valvular AF group were measured. The results demonstrated that TLR2 levels in the non-valvular AF group were significantly higher than in the control group (median, 4682 vs. 3866 sites/cell; P < 0.01). Moreover, non-valvular AF patients had significantly higher IL-6 levels than controls. However, there was no significant difference in CRP levels between the two groups. It was observed in 44 AF patients, in whom pulmonary vein isolation was confirmed to be successful, that the LAVI significantly diminished 1 month after ablation (median, 33.6 vs. 29.5 ml/m²; P < 0.001), but not the TLR2 and IL-6 levels. Our results implied that an infectious inflammation may participate in the pathogenesis of non-valvular AF.
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