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Budzyń M, Gryszczyńska B, Begier-Krasińska B, Kaja E, Mikołajczak P, Kujawski R, Grupińska J, Iskra M, Tykarski A, Kaczmarek M. Decreased toll-like receptor 4 and CD11b/CD18 expression on peripheral monocytes of hypertensive patients correlates with a lesser extent of endothelial damage: a preliminary study. J Hypertens 2024; 42:471-483. [PMID: 37937521 DOI: 10.1097/hjh.0000000000003617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
BACKGROUND Low-grade chronic inflammation is recognized to contribute to the physiopathology of arterial hypertension. Therefore, this study aimed to assess the pro-inflammatory phenotype of peripheral monocytes of hypertensive patients by analyzing Toll-like receptor 4 (TLR4) and CD11b/CD18 surface expression. In the second part, the influence of phenotypic alterations of monocytes on the endothelial status reflected by circulating endothelial cells (CECs) was evaluated. PATIENTS The study included 60 patients with arterial hypertension, who were divided into two subgroups based on the disease severity according to the applicable criteria. The mild hypertension and resistant hypertension groups included 30 patients each. The control group consisted of 33 normotensive volunteers matched for age and sex. RESULTS Both in the entire group of patients and individual subgroups, reduced surface expression of TLR4 and CD11b/CD18 was found compared to normotensive volunteers. A reduced percentage of monocytes with the CD14 + TLR4 + immunophenotype was correlated with a lower MFI level of CD18 and CD11b in the entire group of patients and after division only in the mild hypertension group. Reduced surface expression of TLR4 in hypertensive patients correlated with a lower number of CECs. This relationship was not observed in the resistant hypertension group; instead, an independent effect of reduced CD11b/CD18 expression on the reduction of CEC number was demonstrated. CONCLUSION Our preliminary study showed for the first time that hypertension of varying severity is accompanied by phenotypic changes in monocytes, manifested by reduced surface expression of both TLR4 and CD11b/CD18. These phenotypic changes were associated with a reduced degree of endothelial injury. Our study opens a new, unexplored area of research on the protective features of peripheral monocytes in hypertension.
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Affiliation(s)
- Magdalena Budzyń
- Chair and Department of Medical Chemistry and Laboratory Medicine
| | | | | | - Elżbieta Kaja
- Chair and Department of Medical Chemistry and Laboratory Medicine
| | | | | | - Joanna Grupińska
- Chair and Department of Medical Chemistry and Laboratory Medicine
| | - Maria Iskra
- Chair and Department of Medical Chemistry and Laboratory Medicine
| | | | - Mariusz Kaczmarek
- Department of Cancer Immunology, Poznan University of Medical Sciences
- Gene Therapy Unit, Department of Diagnostics and Cancer Immunology, Greater Poland Cancer Center, Poznan, Poland
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Copur S, Peltek IB, Mutlu A, Tanriover C, Kanbay M. A new immune disease: systemic hypertension. Clin Kidney J 2023; 16:1403-1419. [PMID: 37664577 PMCID: PMC10469084 DOI: 10.1093/ckj/sfad059] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Indexed: 09/05/2023] Open
Abstract
Systemic hypertension is the most common medical comorbidity affecting the adult population globally, with multiple associated outcomes including cerebrovascular diseases, cardiovascular diseases, vascular calcification, chronic kidney disease, metabolic syndrome and mortality. Despite advancements in the therapeutic field approximately one in every five adult patients with hypertension is classified as having treatment-resistant hypertension, indicating the need for studies to provide better understanding of the underlying pathophysiology and the need for more therapeutic targets. Recent pre-clinical studies have demonstrated the role of the innate and adaptive immune system including various cell types and cytokines in the pathophysiology of hypertension. Moreover, pre-clinical studies have indicated the potential beneficial effects of immunosuppressant medications in the control of hypertension. Nevertheless, it is unclear whether such pathophysiological mechanisms and therapeutic alternatives are applicable to human subjects, while this area of research is undoubtedly a rapidly growing field.
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Affiliation(s)
- Sidar Copur
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Ibrahim B Peltek
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Ali Mutlu
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Cem Tanriover
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Mehmet Kanbay
- Department of Medicine, Section of Nephrology, Koc University School of Medicine, Istanbul, Turkey
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Ma J, Li Y, Yang X, Liu K, Zhang X, Zuo X, Ye R, Wang Z, Shi R, Meng Q, Chen X. Signaling pathways in vascular function and hypertension: molecular mechanisms and therapeutic interventions. Signal Transduct Target Ther 2023; 8:168. [PMID: 37080965 PMCID: PMC10119183 DOI: 10.1038/s41392-023-01430-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 03/03/2023] [Accepted: 03/31/2023] [Indexed: 04/22/2023] Open
Abstract
Hypertension is a global public health issue and the leading cause of premature death in humans. Despite more than a century of research, hypertension remains difficult to cure due to its complex mechanisms involving multiple interactive factors and our limited understanding of it. Hypertension is a condition that is named after its clinical features. Vascular function is a factor that affects blood pressure directly, and it is a main strategy for clinically controlling BP to regulate constriction/relaxation function of blood vessels. Vascular elasticity, caliber, and reactivity are all characteristic indicators reflecting vascular function. Blood vessels are composed of three distinct layers, out of which the endothelial cells in intima and the smooth muscle cells in media are the main performers of vascular function. The alterations in signaling pathways in these cells are the key molecular mechanisms underlying vascular dysfunction and hypertension development. In this manuscript, we will comprehensively review the signaling pathways involved in vascular function regulation and hypertension progression, including calcium pathway, NO-NOsGC-cGMP pathway, various vascular remodeling pathways and some important upstream pathways such as renin-angiotensin-aldosterone system, oxidative stress-related signaling pathway, immunity/inflammation pathway, etc. Meanwhile, we will also summarize the treatment methods of hypertension that targets vascular function regulation and discuss the possibility of these signaling pathways being applied to clinical work.
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Affiliation(s)
- Jun Ma
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Yanan Li
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Xiangyu Yang
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Kai Liu
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Xin Zhang
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Xianghao Zuo
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Runyu Ye
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Ziqiong Wang
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Rufeng Shi
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China
| | - Qingtao Meng
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China.
| | - Xiaoping Chen
- Department of Cardiology, West China Hospital, Sichuan University, No. 37, Guo Xue District, Chengdu, Sichuan, 610041, People's Republic of China.
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4
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Benson LN, Guo Y, Deck K, Mora C, Liu Y, Mu S. The link between immunity and hypertension in the kidney and heart. Front Cardiovasc Med 2023; 10:1129384. [PMID: 36970367 PMCID: PMC10034415 DOI: 10.3389/fcvm.2023.1129384] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/20/2023] [Indexed: 03/11/2023] Open
Abstract
Hypertension is the primary cause of cardiovascular disease, which is a leading killer worldwide. Despite the prevalence of this non-communicable disease, still between 90% and 95% of cases are of unknown or multivariate cause ("essential hypertension"). Current therapeutic options focus primarily on lowering blood pressure through decreasing peripheral resistance or reducing fluid volume, but fewer than half of hypertensive patients can reach blood pressure control. Hence, identifying unknown mechanisms causing essential hypertension and designing new treatment accordingly are critically needed for improving public health. In recent years, the immune system has been increasingly implicated in contributing to a plethora of cardiovascular diseases. Many studies have demonstrated the critical role of the immune system in the pathogenesis of hypertension, particularly through pro-inflammatory mechanisms within the kidney and heart, which, eventually, drive a myriad of renal and cardiovascular diseases. However, the precise mechanisms and potential therapeutic targets remain largely unknown. Therefore, identifying which immune players are contributing to local inflammation and characterizing pro-inflammatory molecules and mechanisms involved will provide promising new therapeutic targets that could lower blood pressure and prevent progression from hypertension into renal or cardiac dysfunction.
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Affiliation(s)
- Lance N. Benson
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, United States
| | | | | | | | | | - Shengyu Mu
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, United States
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Murray EC, Nosalski R, MacRitchie N, Tomaszewski M, Maffia P, Harrison DG, Guzik TJ. Therapeutic targeting of inflammation in hypertension: from novel mechanisms to translational perspective. Cardiovasc Res 2021; 117:2589-2609. [PMID: 34698811 PMCID: PMC9825256 DOI: 10.1093/cvr/cvab330] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 10/14/2021] [Accepted: 10/21/2021] [Indexed: 01/18/2023] Open
Abstract
Both animal models and human observational and genetic studies have shown that immune and inflammatory mechanisms play a key role in hypertension and its complications. We review the effects of immunomodulatory interventions on blood pressure, target organ damage, and cardiovascular risk in humans. In experimental and small clinical studies, both non-specific immunomodulatory approaches, such as mycophenolate mofetil and methotrexate, and medications targeting T and B lymphocytes, such as tacrolimus, cyclosporine, everolimus, and rituximab, lower blood pressure and reduce organ damage. Mechanistically targeted immune interventions include isolevuglandin scavengers to prevent neo-antigen formation, co-stimulation blockade (abatacept, belatacept), and anti-cytokine therapies (e.g. secukinumab, tocilizumab, canakinumab, TNF-α inhibitors). In many studies, trial designs have been complicated by a lack of blood pressure-related endpoints, inclusion of largely normotensive study populations, polypharmacy, and established comorbidities. Among a wide range of interventions reviewed, TNF-α inhibitors have provided the most robust evidence of blood pressure lowering. Treatment of periodontitis also appears to deliver non-pharmacological anti-hypertensive effects. Evidence of immunomodulatory drugs influencing hypertension-mediated organ damage are also discussed. The reviewed animal models, observational studies, and trial data in humans, support the therapeutic potential of immune-targeted therapies in blood pressure lowering and in hypertension-mediated organ damage. Targeted studies are now needed to address their effects on blood pressure in hypertensive individuals.
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Affiliation(s)
- Eleanor C Murray
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA Glasgow, UK
| | - Ryszard Nosalski
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA Glasgow, UK,Department of Internal Medicine, Collegium Medicum, Jagiellonian University, 31-008 Kraków, Poland
| | - Neil MacRitchie
- Centre for Immunobiology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA Glasgow, UK
| | - Maciej Tomaszewski
- Division of Cardiovascular Sciences, Faculty of Medicine, Biology and Health, University of Manchester, M13 9PL Manchester, UK,Manchester Heart Centre and Manchester Academic Health Science Centre, Manchester University NHS Foundation Trust, M13 9WL Manchester, UK
| | - Pasquale Maffia
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA Glasgow, UK,Centre for Immunobiology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8TA Glasgow, UK,Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy
| | - David G Harrison
- Division of Clinical Pharmacology, Department of Medicine, Vanderbildt University Medical Centre, Nashville, 37232 TN, USA
| | - Tomasz J Guzik
- Corresponding author. Tel: +44 141 3307590; fax: +44 141 3307590, E-mail:
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Li T, Jing J, Dong N, Liu X, Ma C, Yang J. TLR4 rs1927914 polymorphism contributes to serum TLR4 levels in patients with aortic aneurysm. Exp Mol Pathol 2021; 119:104609. [PMID: 33516663 DOI: 10.1016/j.yexmp.2021.104609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/09/2020] [Accepted: 01/20/2021] [Indexed: 12/25/2022]
Abstract
Toll-like receptor 4 (TLR4) is a crucial regulator of inflammatory reactions and vascular remodeling. Elevated TLR4 expression has been proved to be correlated with an increased risk of aortic aneurysm (AA). This study aimed to explore the influence of TLR4 gene polymorphisms on TLR4 expression levels and its probable functional significance in AA disease. A total of 294 AA patients and 285 controls were enrolled in the study and serum TLR4 levels were detected by ELISA. All the participants were genotyped for two tag-SNPs in TLR4 (rs1927914 in the promoter region and rs11536889 in the 3'-untranslated region) using the KASP method. Relative luciferase activity was measured by the dual-luciferase reporter assay system. The rs1927914 TC, TC/CC genotypes and C allele showed associations with increased serum TLR4 levels in the total population and AA patients (all P<0.05). Further stratified analysis demonstrated that AA subjects with TC or TC/CC genotype of rs1927914 had significantly higher serum levels of TLR4 than those with TT genotype in male, age>60y, hypertension, diabetes, TAA type and size>5.0 cm subgroups (all P<0.05). In binary logistic analysis, rs1927914 TC genotype and dominant model presented significant associations with high TLR4 levels (OR = 1.579 and 1.431, P = 0.020 and 0.049, respectively) after adjusting age, hypertension and diabetes. However, rs11536889 polymorphism had no significant influence on serum TLR4 levels. Regarding rs1927914, luciferase activity of the C allele construct was significantly increased in comparison with the T allele construct (0.589 ± 0.004 vs. 0.340 ± 0.014, P<0.001). Our results provided evidence that rs1927914 polymorphism contributed to serum TLR4 levels, possibly by influencing promoter activity of TLR4, and could be a novel genetic factor in the formation of AA.
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Affiliation(s)
- Tan Li
- Department of Cardiovascular Ultrasound, the First Hospital of China Medical University, Shenyang 110001, China
| | - Jingjing Jing
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Hospital of China Medical University, Shenyang 110001, China
| | - Nannan Dong
- Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Hospital of China Medical University, Shenyang 110001, China
| | - Xiaozheng Liu
- Department of Cardiovascular Ultrasound, the First Hospital of China Medical University, Shenyang 110001, China
| | - Chunyan Ma
- Department of Cardiovascular Ultrasound, the First Hospital of China Medical University, Shenyang 110001, China.
| | - Jun Yang
- Department of Cardiovascular Ultrasound, the First Hospital of China Medical University, Shenyang 110001, China.
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7
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Zhang RM, McNerney KP, Riek AE, Bernal‐Mizrachi C. Immunity and Hypertension. Acta Physiol (Oxf) 2021; 231:e13487. [PMID: 32359222 DOI: 10.1111/apha.13487] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/24/2020] [Accepted: 04/25/2020] [Indexed: 12/15/2022]
Abstract
Hypertension is the primary cause of cardiovascular mortality. Despite multiple existing treatments, only half of those with the disease achieve adequate control. Therefore, understanding the mechanisms causing hypertension is essential for the development of novel therapies. Many studies demonstrate that immune cell infiltration of the vessel wall, kidney and central nervous system, as well as their counterparts of oxidative stress, the renal renin-angiotensin system (RAS) and sympathetic tone play a critical role in the development of hypertension. Genetically modified mice lacking components of innate and/or adaptive immunity confirm the importance of chronic inflammation in hypertension and its complications. Depletion of immune cells improves endothelial function, decreases oxidative stress, reduces vascular tone and prevents renal interstitial infiltrates, sodium retention and kidney damage. Moreover, the ablation of microglia or central nervous system perivascular macrophages reduces RAS-induced inflammation and prevents sympathetic nervous system activation and hypertension. Therefore, understanding immune cell functioning and their interactions with tissues that regulate hypertensive responses may be the future of novel antihypertensive therapies.
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Affiliation(s)
- Rong M. Zhang
- Department of Medicine Division of Endocrinology, Metabolism, and Lipid Research Washington University School of Medicine St. Louis MO USA
| | - Kyle P. McNerney
- Department of Pediatrics Washington University School of Medicine St. Louis MO USA
| | - Amy E. Riek
- Department of Medicine Division of Endocrinology, Metabolism, and Lipid Research Washington University School of Medicine St. Louis MO USA
| | - Carlos Bernal‐Mizrachi
- Department of Medicine Division of Endocrinology, Metabolism, and Lipid Research Washington University School of Medicine St. Louis MO USA
- Department of Cell Biology and Physiology Washington University School of Medicine St. Louis MO USA
- Department of Medicine VA Medical Center St. Louis MO USA
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8
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Wong SK, Chin KY, Ima-Nirwana S. Toll-like Receptor as a Molecular Link between Metabolic Syndrome and Inflammation: A Review. Curr Drug Targets 2020; 20:1264-1280. [PMID: 30961493 DOI: 10.2174/1389450120666190405172524] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 03/29/2019] [Accepted: 04/01/2019] [Indexed: 02/07/2023]
Abstract
Metabolic Syndrome (MetS) involves a cluster of five conditions, i.e. obesity, hyperglycaemia, hypertension, hypertriglyceridemia and low High-Density Lipoprotein (HDL) cholesterol. All components of MetS share an underlying chronic inflammatory aetiology, manifested by increased levels of pro-inflammatory cytokines. The pathogenic role of inflammation in the development of MetS suggested that toll-like receptor (TLR) activation may trigger MetS. This review summarises the supporting evidence on the interactions between MetS and TLR activation, bridged by the elevation of TLR ligands during MetS. The regulatory circuits mediated by TLR activation, which modulates signal propagation, leading to the state of chronic inflammation, are also discussed. Taken together, TLR activation could be the molecular basis in the development of MetS-induced inflammation.
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Affiliation(s)
- Sok Kuan Wong
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Kok-Yong Chin
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Soelaiman Ima-Nirwana
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Malaysia
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The Association of rs1898830 in Toll-Like Receptor 2 with Lipids and Blood Pressure. J Cardiovasc Dev Dis 2020; 7:jcdd7030024. [PMID: 32650372 PMCID: PMC7569770 DOI: 10.3390/jcdd7030024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/29/2020] [Accepted: 07/06/2020] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Toll-like receptors (TLRs) are important components of the innate immune system, involved in establishing immunity to infections. Apart from being implicated in immunity, numerous studies have reported that many TLRs, including TLR2, are involved in the pathogenesis of cardiovascular diseases and their risk factors. Since rs1898830 is associated with TLR2-mediated cellular activation, we aimed to study its association with CVD risk factors, such as lipid levels and hypertension. METHODS A cross-sectional study was conducted on 460 individuals free from chronic diseases. Clinical and biological data were collected and DNA was extracted and genotyped using Kompetitive allele specific PCR (KASP™). Multiple logistic regression models, adjusted for six covariates, were used. A power calculation analysis was also performed. RESULTS We found that rs1898830 in TLR2 was positively associated with hypertension (OR = 2.18, p = 0.03) and negatively associated with high-density lipoprotein cholesterol (OR = 0.66, p = 0.05). In contrast, no relation was found with total cholesterol and low-density lipoprotein cholesterol. CONCLUSION The present results provide additional evidence supporting the implication of TLR2 in CVD risk factors.
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Drummond GR, Vinh A, Guzik TJ, Sobey CG. Immune mechanisms of hypertension. Nat Rev Immunol 2020; 19:517-532. [PMID: 30992524 DOI: 10.1038/s41577-019-0160-5] [Citation(s) in RCA: 239] [Impact Index Per Article: 59.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hypertension affects 30% of adults and is the leading risk factor for heart attack and stroke. Traditionally, hypertension has been regarded as a disorder of two systems that are involved in the regulation of salt-water balance and cardiovascular function: the renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system (SNS). However, current treatments that aim to limit the influence of the RAAS or SNS on blood pressure fail in ~40% of cases, which suggests that other mechanisms must be involved. This Review summarizes the clinical and experimental evidence supporting a contribution of immune mechanisms to the development of hypertension. In this context, we highlight the immune cell subsets that are postulated to either promote or protect against hypertension through modulation of cardiac output and/or peripheral vascular resistance. We conclude with an appraisal of knowledge gaps still to be addressed before immunomodulatory therapies might be applied to at least a subset of patients with hypertension.
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Affiliation(s)
- Grant R Drummond
- Centre for Cardiovascular Biology and Disease Research, Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Victoria, Australia.
| | - Antony Vinh
- Centre for Cardiovascular Biology and Disease Research, Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Victoria, Australia
| | - Tomasz J Guzik
- Department of Medicine, Jagiellonian University, Collegium Medicum, Krakow, Poland.,BHF Centre of Research Excellence, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| | - Christopher G Sobey
- Centre for Cardiovascular Biology and Disease Research, Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Victoria, Australia
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La participación de la inmunidad en la patogenia de la hipertensión arterial. Nefrologia 2020; 40:1-3. [DOI: 10.1016/j.nefro.2019.04.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 04/17/2019] [Accepted: 04/28/2019] [Indexed: 01/08/2023] Open
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12
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High Mobility Group Box 1 Mediates TMAO-Induced Endothelial Dysfunction. Int J Mol Sci 2019; 20:ijms20143570. [PMID: 31336567 PMCID: PMC6678463 DOI: 10.3390/ijms20143570] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/12/2019] [Accepted: 07/15/2019] [Indexed: 12/22/2022] Open
Abstract
The intestinal microbe-derived metabolite trimethylamine N-oxide (TMAO) is implicated in the pathogenesis of cardiovascular diseases (CVDs). The molecular mechanisms of how TMAO induces atherosclerosis and CVDs’ progression are still unclear. In this regard, high-mobility group box protein 1 (HMGB1), an inflammatory mediator, has been reported to disrupt cell–cell junctions, resulting in vascular endothelial hyper permeability leading to endothelial dysfunction. The present study tested whether TMAO associated endothelial dysfunction results via HMGB1 activation. Biochemical and RT-PCR analysis showed that TMAO increased the HMGB1 expression in a dose-dependent manner in endothelial cells. However, prior treatment with glycyrrhizin, an HMGB1 binder, abolished the TMAO-induced HMGB1 production in endothelial cells. Furthermore, Western blot and immunofluorescent analysis showed significant decrease in the expression of cell–cell junction proteins ZO-2, Occludin, and VE-cadherin in TMAO treated endothelial cells compared with control cells. However, prior treatment with glycyrrhizin attenuated the TMAO-induced cell–cell junction proteins’ disruption. TMAO increased toll-like receptor 4 (TLR4) expression in endothelial cells. Inhibition of TLR4 expression by TLR4 siRNA protected the endothelial cells from TMAO associated tight junction protein disruption via HMGB1. In conclusion, our results demonstrate that HMGB1 is one of the important mediators of TMAO-induced endothelial dysfunction.
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13
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Gogulamudi VR, Mani I, Subramanian U, Pandey KN. Genetic disruption of Npr1 depletes regulatory T cells and provokes high levels of proinflammatory cytokines and fibrosis in the kidneys of female mutant mice. Am J Physiol Renal Physiol 2019; 316:F1254-F1272. [PMID: 30943067 DOI: 10.1152/ajprenal.00621.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The present study was designed to determine the effects of gene knockout of guanylyl cyclase/natriuretic peptide receptor-A (GC-A/NPRA) on immunogenic responses affecting kidney function and blood pressure (BP) in Npr1 (coding for GC-A/NPRA)-null mutant mice. We used female Npr1 gene-disrupted (Npr1-/-, 0 copy), heterozygous (Npr1+/-, 1 copy), wild-type (Npr1+/+, 2 copy), and gene-duplicated (Npr1++/++, 4 copy) mice. Expression levels of Toll-like receptor (TLR)2/TLR4 mRNA were increased 4- to 5-fold in 1-copy mice and 6- to 10-fold in 0-copy mice; protein levels were increased 2.5- to 3-fold in 1-copy mice and 4- to 5-fold in 0-copy mice. Expression of proinflammatory cytokines and BP was significantly elevated in 1-copy and 0-copy mice compared with 2-copy and 4-copy mice. In addition, 0-copy and 1-copy mice exhibited drastic reductions in regulatory T cells (Tregs). After rapamycin treatment, Tregs were increased by 17% (P < 0.001) in 0-copy mice and 8% (P < 0.001) in 1-copy mice. Renal mRNA and protein levels of TLR2 and TLR4 were decreased by 70% in 0-copy mice and 50% in 1-copy mice. There were significantly higher levels of Tregs and very low levels of TLR2/TLR4 expression in 4-copy mice (P < 0.001). These findings indicate that the disruption of Npr1 in female mice triggers renal immunogenic pathways, which transactivate the expression of proinflammatory cytokines and renal fibrosis with elevated BP in mutant animals. The data suggest that rapamycin treatment attenuates proinflammatory cytokine expression, dramatically increases anti-inflammatory cytokines, and substantially reduces BP and renal fibrosis in mutant animals.
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Affiliation(s)
| | - Indra Mani
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine , New Orleans, Louisiana
| | - Umadevi Subramanian
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine , New Orleans, Louisiana
| | - Kailash N Pandey
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine , New Orleans, Louisiana
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Li J, Xiao X, Wei W, Ding H, Yue Y, Tian Y, Nabar NR, Liu Z, Yang Z, Wang M. Inhibition of angiotensin II receptor I prevents inflammation and bone loss in periodontitis. J Periodontol 2018; 90:208-216. [PMID: 30066953 DOI: 10.1002/jper.17-0753] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 02/21/2018] [Accepted: 02/28/2018] [Indexed: 02/05/2023]
Abstract
BACKGROUND Periodontal disease is characterized by alveolar bone destruction and degenerative lesions of the periodontal ligament (PDL); it is initiated by bacterial infection of the oral cavity, but the clinical effects are secondary to an aberrant host immune response. Primary hypertension (PH), which causes significant morbidity and mortality worldwide, has also been shown to be an inflammatory disease characterized by aberrant immune cell infiltration and activation. Clinical retrospective studies have shown a link between PH and periodontitis with PH exacerbating periodontitis and vice versa, but the pathophysiologic mechanisms responsible for this remain unknown. METHODS In this study, we investigate the underlying mechanisms behind PH exacerbation of periodontitis by using a bacteria-induced periodontitis model in normotensive and hypertensive (Nos3-/- ) mice treated with or without an Angiotensin II (Ang II) specific receptor 1 (AT1) antagonist, losartan. The histologic analyses including immunohistochemistry, immunofluorescence were carried out. The qRT-PCR and ELISAs were applied for the target gene and protein detection. RESULTS We find that PH worsens bone resorption and PDL destruction in periodontitis and that treatment with losartan, rescues this. We also show that PH increases dendritic cell (DC) and osteoclast (OC) infiltration in periodontitis, which is also dependent on Ang II. Finally, we show that PH augments the pro-inflammatory state in periodontitis infiltrating DCs in an Ang II-dependent manner and use in vitro studies to show that Ang II directly augments DC Toll-like receptor 4 (TLR4) signaling. CONCLUSION Our studies show a central role for Ang II as a pro-inflammatory Toll-like receptor mediator in the pathogenesis of PH-exacerbated periodontitis, indicating that Ang II may be a reasonable target in patients with PH and periodontitis comorbidity.
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Affiliation(s)
- Jinle Li
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Xun Xiao
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Wei Wei
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Handong Ding
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Yuan Yue
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Ye Tian
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Neel R Nabar
- Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA
| | - Zhaohui Liu
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Zheng Yang
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Min Wang
- The State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, People's Republic of China
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15
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Li T, Jing JJ, Sun LP, Gong YH, Dong NN, Yang J, Yuan Y. Serum Toll-like receptor 4: A novel and promising biomarker for identification of aortic aneurysmal diseases. Clin Chim Acta 2018; 483:69-75. [DOI: 10.1016/j.cca.2018.04.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 01/16/2023]
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16
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Rodriguez-Iturbe B, Pons H, Johnson RJ. Role of the Immune System in Hypertension. Physiol Rev 2017; 97:1127-1164. [PMID: 28566539 PMCID: PMC6151499 DOI: 10.1152/physrev.00031.2016] [Citation(s) in RCA: 256] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 03/02/2017] [Accepted: 03/02/2017] [Indexed: 02/07/2023] Open
Abstract
High blood pressure is present in more than one billion adults worldwide and is the most important modifiable risk factor of death resulting from cardiovascular disease. While many factors contribute to the pathogenesis of hypertension, a role of the immune system has been firmly established by a large number of investigations from many laboratories around the world. Immunosuppressive drugs and inhibition of individual cytokines prevent or ameliorate experimental hypertension, and studies in genetically-modified mouse strains have demonstrated that lymphocytes are necessary participants in the development of hypertension and in hypertensive organ injury. Furthermore, immune reactivity may be the driving force of hypertension in autoimmune diseases. Infiltration of immune cells, oxidative stress, and stimulation of the intrarenal angiotensin system are induced by activation of the innate and adaptive immunity. High blood pressure results from the combined effects of inflammation-induced impairment in the pressure natriuresis relationship, dysfunctional vascular relaxation, and overactivity of the sympathetic nervous system. Imbalances between proinflammatory effector responses and anti-inflammatory responses of regulatory T cells to a large extent determine the severity of inflammation. Experimental and human studies have uncovered autoantigens (isoketal-modified proteins and heat shock protein 70) of potential clinical relevance. Further investigations on the immune reactivity in hypertension may result in the identification of new strategies for the treatment of the disease.
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Affiliation(s)
- Bernardo Rodriguez-Iturbe
- Renal Service, Hospital Universitario, Universidad del Zulia, and Instituto Venezolano de Investigaciones Científicas (IVIC)-Zulia, Maracaibo, Venezuela; and Division of Renal Diseases and Hypertension, University of Colorado, Anschutz Campus, Aurora, Colorado
| | - Hector Pons
- Renal Service, Hospital Universitario, Universidad del Zulia, and Instituto Venezolano de Investigaciones Científicas (IVIC)-Zulia, Maracaibo, Venezuela; and Division of Renal Diseases and Hypertension, University of Colorado, Anschutz Campus, Aurora, Colorado
| | - Richard J Johnson
- Renal Service, Hospital Universitario, Universidad del Zulia, and Instituto Venezolano de Investigaciones Científicas (IVIC)-Zulia, Maracaibo, Venezuela; and Division of Renal Diseases and Hypertension, University of Colorado, Anschutz Campus, Aurora, Colorado
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17
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Mao S, Gu T, Zhong F, Fan R, Zhu F, Ren P, Yin F, Zhang L. Hypomethylation of the Toll-like receptor-2 gene increases the risk of essential hypertension. Mol Med Rep 2017; 16:964-970. [PMID: 28560381 DOI: 10.3892/mmr.2017.6653] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 03/13/2017] [Indexed: 11/06/2022] Open
Abstract
Studies on the etiology of essential hypertension (EH) have demonstrated that chronic inflammation contributes to the onset and development of elevated blood pressure. Toll‑like receptors (TLRs), important immune receptors, serve a role in chronic inflammation and are associated with EH. In the present study, 96 patients with EH, and 96 age‑ and sex‑matched healthy controls were recruited, and eight cytosine‑phosphate‑guanine (CpG) dinucleotides (CpG1‑8) were analyzed using bisulfite pyrosequencing technology. It was observed that the methylation levels of all of the eight CpG dinucleotides were decreased in the EH group compared with the control group; however, only CpG1 (2.83±1.34 vs. 3.44±1.75; P=0.009), CpG6 (3.58±3.64 vs. 8.30±4.13; P<0.001) and CpG8 (8.91±5.32 vs. 11.33±3.87; P<0.001) were significantly different, as demonstrated by paired t‑test analysis. In addition, logistic regression analysis demonstrated that CpG6 hypomethylation was a risk factor of EH (odds ratio=1.10; adjusted P=0.009), and CpG6 methylation level was observed to be negatively correlated with systolic blood pressure (r=‑0.304; P<0.001) and diastolic blood pressure (r=‑0.329; P<0.001). Additionally, receiver operating characteristic curve analysis demonstrated that a methylation level of 7.5% for CpG6 (area under the curve, 0.834; P<0.001) was an appropriate threshold value to predict the risk of EH. With generalized multifactor dimensionality reduction, a potential gene‑gene interaction between CpG6 and CpG8 (P=0.001), and gene‑environment interactions between smoking, alcohol consumption, CpG6, CpG7 and CpG8 (P=0.011), were observed. In conclusion, the results of the present study demonstrated that hypomethylation of the TLR2 promoter, particularly CpG6, was associated with the risk of EH in this population. Additionally, a gene‑gene interaction between CpG6 and CpG8, and interactions between environmental factors, including smoking and alcohol consumption, and CpG6, CpG7 and CpG8, may be associated with the risk of EH.
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Affiliation(s)
- Shuqi Mao
- Department of Preventive Medicine, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang 315211, P.R. China
| | - Tianlun Gu
- Department of Preventive Medicine, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang 315211, P.R. China
| | - Fade Zhong
- The Central Blood Station of Ningbo, Ningbo, Zhejiang 315211, P.R. China
| | - Rui Fan
- Department of Preventive Medicine, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang 315211, P.R. China
| | - Fubao Zhu
- Health and Family Planning Commission of Zhenhai, Ningbo, Zhejiang 315211, P.R. China
| | - Peipei Ren
- Clinical Laboratory, Baizhang Street Community Health Service Center of JiangDong, Ningbo, Zhejiang 315211, P.R. China
| | - Fengying Yin
- Clinical Laboratory, The First Hospital of Ningbo, Ningbo, Zhejiang 315010, P.R. China
| | - Lina Zhang
- Department of Preventive Medicine, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang 315211, P.R. China
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Simundic T, Jelakovic B, Dzumhur A, Turk T, Sahinovic I, Dobrosevic B, Takac B, Barbic J. Interleukin 17A and Toll-like Receptor 4 in Patients with Arterial Hypertension. Kidney Blood Press Res 2017; 42:99-108. [DOI: 10.1159/000471900] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 01/17/2017] [Indexed: 11/19/2022] Open
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19
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Abais-Battad JM, Dasinger JH, Fehrenbach DJ, Mattson DL. Novel adaptive and innate immunity targets in hypertension. Pharmacol Res 2017; 120:109-115. [PMID: 28336371 DOI: 10.1016/j.phrs.2017.03.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 02/03/2017] [Accepted: 03/17/2017] [Indexed: 01/11/2023]
Abstract
Hypertension is a worldwide epidemic and global health concern as it is a major risk factor for the development of cardiovascular diseases. A relationship between the immune system and its contributing role to the pathogenesis of hypertension has been long established, but substantial advancements within the last few years have dissected specific causal molecular mechanisms. This review will briefly examine these recent studies exploring the involvement of either innate or adaptive immunity pathways. Such pathways to be discussed include innate immunity factors such as antigen presenting cells and pattern recognition receptors, adaptive immune elements including T and B lymphocytes, and more specifically, the emerging role of T regulatory cells, as well as the potential of cytokines and chemokines to serve as signaling messengers connecting innate and adaptive immunity. Together, we summarize these studies to provide new perspective for what will hopefully lead to more targeted approaches to manipulate the immune system as hypertensive therapy.
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Affiliation(s)
| | | | | | - David L Mattson
- Department of Physiology, Medical College of Wisconsin, United States
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20
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Odashiro K, Saito K, Arita T, Maruyama T, Fujino T, Akashi K. Impaired deformability of circulating erythrocytes obtained from nondiabetic hypertensive patients: investigation by a nickel mesh filtration technique. Clin Hypertens 2015; 21:17. [PMID: 26893927 PMCID: PMC4750801 DOI: 10.1186/s40885-015-0030-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 07/10/2015] [Indexed: 11/10/2022] Open
Abstract
Introduction Hypertension is associated with microcirculatory disturbance, and erythrocyte deformability is a major determinant of the microcirculation. However, impairment of erythrocyte deformability in hypertensive patients in relation to antihypertensive treatment is unclear. The present study aimed to investigate this impairment in hypertensive patients under treatment using a highly sensitive and quantitative nickel mesh filtration technique. Methods Deformability was evaluated by filterability, defined as the flow rate of a hematocrit-adjusted erythrocyte suspension relative to that of saline under a specific filtration pressure in a pressure-flow curve obtained by continuous filtration. Baseline characteristics of hypertensive patients (n = 101) and age-matched normotensive subjects (n = 14) were obtained from medical records, and diabetic patients were excluded. Results Erythrocyte deformability in the hypertensive group was significantly (p = 0.010) lower (87.8 ± 2.2 %) than that of the normotensive group (89.4 ± 1.7 %) and inversely proportional (r = −0.303, p = 0.002) to the mean blood pressure (BP) measured on blood sampling for the filtration study. Stepwise multiple regression analysis demonstrated that this impairment was mostly attributable to the mean BP (p = 0.001), whereas current smoking and episodes of stroke or coronary artery disease were not contributors. Discussion These findings indicate that erythrocyte deformability is impaired in the hypertensive patients, which depends on the current BP control rather than target organ damage.
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Affiliation(s)
- Keita Odashiro
- Department of Medicine, Kyushu University, Fukuoka, 812-8582 Japan
| | | | - Takeshi Arita
- Department of Medicine, Kyushu University, Fukuoka, 812-8582 Japan
| | - Toru Maruyama
- Faculty of Art and Science, Kyushu University, Kasuga Kohen 6-1, Kasuga, 816-8580 Japan
| | - Takehiko Fujino
- Institute of Rheological Function of Foods Co., Ltd, Hisayama, 811-2501 Japan
| | - Koichi Akashi
- Department of Medicine, Kyushu University, Fukuoka, 812-8582 Japan
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21
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Hernanz R, Martínez-Revelles S, Palacios R, Martín A, Cachofeiro V, Aguado A, García-Redondo L, Barrús MT, de Batista PR, Briones AM, Salaices M, Alonso MJ. Toll-like receptor 4 contributes to vascular remodelling and endothelial dysfunction in angiotensin II-induced hypertension. Br J Pharmacol 2015; 172:3159-76. [PMID: 25712370 DOI: 10.1111/bph.13117] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 02/17/2015] [Accepted: 02/17/2015] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Toll-like receptor 4 (TLR4) signalling contributes to inflammatory cardiovascular diseases, but its role in hypertension and the associated vascular damage is not known. We investigated whether TLR4 activation contributed to angiotensin II (AngII)-induced hypertension and the associated vascular structural, mechanical and functional alterations. EXPERIMENTAL APPROACH AngII was infused (1.44 mg · kg(-1) · day(-1), s.c.) for 2 weeks in C57BL6 mice, treated with a neutralizing anti-TLR4 antibody or IgG (1 μg · day(-1); systolic BP (SBP) and aortic cytokine levels were measured. Structural, mechanical and contractile properties of aortic and mesenteric arterial segments were measured with myography and histology. RT-PCR and Western blotting were used to analyse these tissues and cultured vascular smooth muscle cells (VSMC) from hypertensive rats (SHR). KEY RESULTS Aortic TLR4 mRNA levels were raised by AngII infusion. Anti-TLR4 antibody treatment of AngII-treated mice normalised: (i) increased SBP and TNF-α, IL-6 and CCL2 levels; (ii) vascular structural and mechanical changes; (iii) altered aortic phenylephrine- and ACh-induced responses; (iv) increased NOX-1 mRNA levels, superoxide anion production and NAD(P)H oxidase activity and effects of catalase, apocynin, ML-171 and Mito-TEMPO on vascular responses; and (v) reduced NO release and effects of L-NAME on phenylephrine-induced contraction. In VSMC, the MyD88 inhibitor ST-2825 reduced AngII-induced NAD(P)H oxidase activity. The TLR4 inhibitor CLI-095 reduced AngII-induced increased phospho-JNK1/2 and p65 NF-κB subunit nuclear protein expression. CONCLUSIONS AND IMPLICATIONS TLR4 up-regulation by AngII contributed to the inflammation, endothelial dysfunction, vascular remodelling and stiffness associated with hypertension by mechanisms involving oxidative stress. MyD88-dependent activation and JNK/NF-κB signalling pathways participated in these alterations.
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Affiliation(s)
- R Hernanz
- Dept. of Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain
| | - S Martínez-Revelles
- Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain.,Dept. of Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
| | - R Palacios
- Dept. of Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain
| | - A Martín
- Dept. of Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain.,Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain
| | - V Cachofeiro
- Dept. of Fisiología, Universidad Complutense de Madrid, Madrid, Spain
| | - A Aguado
- Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain.,Dept. of Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
| | - L García-Redondo
- Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain.,Dept. of Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
| | - M T Barrús
- Dept. of Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - P R de Batista
- Dept. of Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - A M Briones
- Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain.,Dept. of Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
| | - M Salaices
- Instituto de Investigación Hospital Universitario La Paz (IdiPaz), Madrid, Spain.,Dept. of Farmacología, Universidad Autónoma de Madrid, Madrid, Spain
| | - M J Alonso
- Dept. of Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
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22
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Abstract
A large number of investigations have demonstrated the participation of the immune system in the pathogenesis of hypertension. Studies focusing on macrophages and Toll-like receptors have documented involvement of the innate immunity. The requirements of antigen presentation and co-stimulation, the critical importance of T cell-driven inflammation, and the demonstration, in specific conditions, of agonistic antibodies directed to angiotensin II type 1 receptors and adrenergic receptors support the role of acquired immunity. Experimental findings support the concept that the balance between T cell-induced inflammation and T cell suppressor responses is critical for the regulation of blood pressure levels. Expression of neoantigens in response to inflammation, as well as surfacing of intracellular immunogenic proteins, such as heat shock proteins, could be responsible for autoimmune reactivity in the kidney, arteries, and central nervous system. Persisting, low-grade inflammation in these target organs may lead to impaired pressure natriuresis, an increase in sympathetic activity, and vascular endothelial dysfunction that may be the cause of chronic elevation of blood pressure in essential hypertension.
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Affiliation(s)
- Bernardo Rodríguez-Iturbe
- Hospital Universitario y Universidad del Zulia, Maracaibo, Venezuela; Instituto Venezolano de Investigaciones Científicas-Zulia, Maracaibo, Venezuela;
| | - Héctor Pons
- Hospital Universitario y Universidad del Zulia, Maracaibo, Venezuela
| | - Yasmir Quiroz
- Instituto Venezolano de Investigaciones Científicas-Zulia, Maracaibo, Venezuela
| | - Richard J Johnson
- Division of Renal Diseases and Hypertension, University of Colorado, Denver, Colorado
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23
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Dhande I, Ma W, Hussain T. Angiotensin AT2 receptor stimulation is anti-inflammatory in lipopolysaccharide-activated THP-1 macrophages via increased interleukin-10 production. Hypertens Res 2014; 38:21-9. [PMID: 25209104 DOI: 10.1038/hr.2014.132] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 06/19/2014] [Accepted: 07/06/2014] [Indexed: 12/31/2022]
Abstract
Macrophages have an important role in the pathogenesis of hypertension and associated end-organ damage via the activation of the Toll-like receptors, such as Toll-like receptor-4 (TLR4). Accumulating evidence suggests that the angiotensin AT2 receptor (AT2R) has a protective role in pathological conditions involving inflammation and tissue injury. We have recently shown that AT(2)R stimulation is renoprotective, which occurs in part via increased levels of anti-inflammatory interleukin-10 (IL-10) production in renal epithelial cells; however, the role of AT(2)R in the inflammatory activity of macrophages is not known. The present study was designed to investigate whether AT(2)R activation stimulates an anti-inflammatory response in TLR4-induced inflammation. The effects of the anti-inflammatory mechanisms that occurred following pre-treatment with the AT(2)R agonist Compound 21 (C21) (1 μmol ml(-1)) on the cytokine profiles of THP-1 macrophages after activation by lipopolysaccharide (LPS) (1 μg ml(-1)) were studied. The AT(2)R agonist dose-dependently attenuated LPS-induced tumor necrosis factor-α (TNF-α) and IL-6 production but increased IL-10 production. IL-10 was critical for the anti-inflammatory effects of AT(2)R stimulation because the IL-10-neutralizing antibody dose-dependently abolished the AT(2)R-mediated decrease in TNF-α levels. Further, enhanced IL-10 levels were associated with a sustained, selective increase in the phosphorylation of extracellular signal-regulated kinase (ERK1/2) but not p38 mitogen-activated protein kinase (MAPK). Blocking the activation of ERK1/2 before C21 pre-treatment completely abrogated this increased IL-10 production in response to the AT(2)R agonist C21, while there was a partial reduction in IL-10 levels following the inhibition of p38. We conclude that AT(2)R stimulation exerts a novel anti-inflammatory response in THP-1 macrophages via enhanced IL-10 production as a result of sustained, selective ERK1/2 phosphorylation, which may have protective roles in hypertension and associated tissue injury.
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Affiliation(s)
- Isha Dhande
- 1] Department of Pharmacological and Pharmaceutical Sciences, Heart and Kidney Institute, University of Houston, Houston, TX, USA [2] Department of Pharmacal Sciences, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Wanshu Ma
- Department of Pharmacal Sciences, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Tahir Hussain
- 1] Department of Pharmacological and Pharmaceutical Sciences, Heart and Kidney Institute, University of Houston, Houston, TX, USA [2] Department of Pharmacal Sciences, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
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Abstract
Despite intensive research, the exact cause of hypertension remains unknown. Low-grade inflammation has been proposed to play a key role in the pathogenesis of hypertension. Both innate and adaptive immune responses may participate in this process. Several studies have addressed the contribution of adaptive immunity to the pathophysiology of high blood pressure; however, the role of innate immunity is less clear. Innate immunity may be an important mediator of chronic inflammation in hypertension. Slight elevation of blood pressure due to increased sympathetic and/or decreased parasympathetic outflow, or low-grade infections may generate neoantigens and damage-activated molecular patterns (DAMPs) or pathogen-activated molecular patterns (PAMPs), which can trigger Toll-like receptors on innate effector cells. Innate responses, mediated by monocytes, macrophages, dendritic cells and natural killer cells, may contribute to inflammation either directly or by activating adaptive immune responses mediated by T lymphocytes. In this review, we discuss the recent evidence regarding the contribution of different innate effector cells, their response and their mechanisms of activation in hypertension.
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25
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De Batista PR, Palacios R, Martín A, Hernanz R, Médici CT, Silva MASC, Rossi EM, Aguado A, Vassallo DV, Salaices M, Alonso MJ. Toll-like receptor 4 upregulation by angiotensin II contributes to hypertension and vascular dysfunction through reactive oxygen species production. PLoS One 2014; 9:e104020. [PMID: 25093580 PMCID: PMC4122400 DOI: 10.1371/journal.pone.0104020] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 07/06/2014] [Indexed: 12/16/2022] Open
Abstract
Hypertension is considered as a low-grade inflammatory disease, with adaptive immunity being an important mediator of this pathology. TLR4 may have a role in the development of several cardiovascular diseases; however, little is known about its participation in hypertension. We aimed to investigate whether TLR4 activation due to increased activity of the renin-angiotensin system (RAS) contributes to hypertension and its associated endothelial dysfunction. For this, we used aortic segments from Wistar rats treated with a non-specific IgG (1 µg/day) and SHRs treated with losartan (15 mg/kg·day), the non-specific IgG or the neutralizing antibody anti-TLR4 (1 µg/day), as well as cultured vascular smooth muscle cells (VSMC) from Wistar and SHRs. TLR4 mRNA levels were greater in the VSMC and aortas from SHRs compared with Wistar rats; losartan treatment reduced those levels in the SHRs. Treatment of the SHRs with the anti-TLR4 antibody: 1) reduced the increased blood pressure, heart rate and phenylephrine-induced contraction while it improved the impaired acetylcholine-induced relaxation; 2) increased the potentiation of phenylephrine contraction after endothelium removal; and 3) abolished the inhibitory effects of tiron, apocynin and catalase on the phenylephrine-induced response as well as its enhancing effect of acetylcholine-induced relaxation. In SHR VSMCs, angiotensin II increased TLR4 mRNA levels, and losartan reduced that increase. CLI-095, a TLR4 inhibitor, mitigated the increases in NAD(P)H oxidase activity, superoxide anion production, migration and proliferation that were induced by angiotensin II. In conclusion, TLR4 pathway activation due to increased RAS activity is involved in hypertension, and by inducing oxidative stress, this pathway contributes to the endothelial dysfunction associated with this pathology. These results suggest that TLR4 and innate immunity may play a role in hypertension and its associated end-organ damage.
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Affiliation(s)
- Priscila R. De Batista
- Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón, Spain
- Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
| | - Roberto Palacios
- Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - Angela Martín
- Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - Raquel Hernanz
- Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - Cindy T. Médici
- Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
| | - Marito A. S. C. Silva
- Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
| | - Emilly M. Rossi
- Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
| | - Andrea Aguado
- Dept. of Pharmacology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Dalton V. Vassallo
- Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
| | - Mercedes Salaices
- Dept. of Pharmacology, Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail: (MJA); (MS)
| | - María J. Alonso
- Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón, Spain
- * E-mail: (MJA); (MS)
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Houston M. The role of nutrition and nutraceutical supplements in the treatment of hypertension. World J Cardiol 2014; 6:38-66. [PMID: 24575172 PMCID: PMC3935060 DOI: 10.4330/wjc.v6.i2.38] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 10/22/2013] [Accepted: 12/17/2013] [Indexed: 02/06/2023] Open
Abstract
Vascular biology, endothelial and vascular smooth muscle and cardiac dysfunction play a primary role in the initiation and perpetuation of hypertension, cardiovascular disease and target organ damage. Nutrient-gene interactions and epigenetics are predominant factors in promoting beneficial or detrimental effects in cardiovascular health and hypertension. Macronutrients and micronutrients can prevent, control and treat hypertension through numerous mechanisms related to vascular biology. Oxidative stress, inflammation and autoimmune dysfunction initiate and propagate hypertension and cardiovascular disease. There is a role for the selected use of single and component nutraceutical supplements, vitamins, antioxidants and minerals in the treatment of hypertension based on scientifically controlled studies which complement optimal nutrition, coupled with other lifestyle modifications.
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Affiliation(s)
- Mark Houston
- Mark Houston, Hypertension Institute, Saint Thomas Medical Plaza, Nashville, TN 37205, United States
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Houston M. Nutrition and nutraceutical supplements for the treatment of hypertension: part I. J Clin Hypertens (Greenwich) 2013; 15:752-7. [PMID: 24088285 PMCID: PMC8033896 DOI: 10.1111/jch.12188] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/19/2013] [Accepted: 07/21/2013] [Indexed: 12/16/2022]
Abstract
Vascular biology, endothelial and vascular smooth muscle, and cardiac dysfunction play a primary role in the initiation and perpetuation of hypertension, cardiovascular disease, and target organ damage. Nutrient-gene interactions and epigenetics are predominant factors in promoting beneficial or detrimental effects in cardiovascular health and hypertension. Macronutrients and micronutrients may be able to prevent, control, or treat hypertension through numerous mechanisms related to vascular biology or other mechanisms. Oxidative stress, inflammation, and autoimmune dysfunction are some of the primary factors that initiate and propagate hypertension and cardiovascular disease. The literature suggests that there may be a complementary role of single and component nutraceutical supplements, vitamins, antioxidants, and minerals in the treatment of hypertension when combined with optimal nutrition and other lifestyle modifications. However, many of these studies are small and do not have long-term follow-up for efficacy and safety. The role of these nutrition and nutraceutical supplements will require careful review and additional studies to determine their exact role in the management of hypertension.
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Affiliation(s)
- Mark Houston
- Department of Medicine, Vanderbilt University School of Medicine, Hypertension Institute of Nashville, Saint Thomas Medical Group and Health ServicesSaint Thomas HospitalNashvilleTN
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Maiwald S, Zwetsloot PP, Sivapalaratnam S, Dallinga-Thie GM. Monocyte gene expression and coronary artery disease. Curr Opin Clin Nutr Metab Care 2013; 16:411-7. [PMID: 23739627 DOI: 10.1097/mco.0b013e32836236f9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE OF REVIEW Despite current therapy, coronary artery disease (CAD) remains the major cause of morbidity and mortality worldwide. CAD is the consequence of a complex array of deranged metabolic processes including the immune system. In this context, monocytes and macrophages are indisputable players. Thus, monocyte gene expression analysis could be a powerful tool to provide new insights in the pathophysiology of CAD and improve identification of individuals at risk. We discuss current literature assessing monocyte gene expression and its association with CAD. RECENT FINDINGS Monocyte surface markers CD14 ⁺⁺and CD16⁺ have been established as biomarkers for increased cardiovascular disease risk in a large number of studies. More in-depth gene expression analysis identified several interesting genes, such as ABCA1, CD36 and MSR1 with an increased expression in circulating monocytes from patients with CAD. The results for CD36 were replicated in one other study. For ABCA1 and MSR1 conflicting data are published. SUMMARY Recent findings indicate that genetic differences exist in circulating monocytes of patients suffering from CAD, giving us more insights into the underlying mechanisms. However, larger studies are required to prove that monocytes' expression signature could serve as a marker for diagnostic purposes in the future.
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Affiliation(s)
- Stephanie Maiwald
- Department of Vascular Medicine, Academic Medical Center, Amsterdam, The Netherlands
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Bellavia A, Urch B, Speck M, Brook RD, Scott JA, Albetti B, Behbod B, North M, Valeri L, Bertazzi PA, Silverman F, Gold D, Baccarelli AA. DNA hypomethylation, ambient particulate matter, and increased blood pressure: findings from controlled human exposure experiments. J Am Heart Assoc 2013; 2:e000212. [PMID: 23782920 PMCID: PMC3698788 DOI: 10.1161/jaha.113.000212] [Citation(s) in RCA: 163] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Short-term exposures to fine (<2.5 μm aerodynamic diameter) ambient particulate-matter (PM) have been related with increased blood pressure (BP) in controlled-human exposure and community-based studies. However, whether coarse (2.5 to 10 μm) PM exposure increases BP is uncertain. Recent observational studies have linked PM exposures with blood DNA hypomethylation, an epigenetic alteration that activates inflammatory and vascular responses. No experimental evidence is available to confirm those observational data and demonstrate the relations between PM, hypomethylation, and BP. METHODS AND RESULTS We conducted a cross-over trial of controlled-human exposure to concentrated ambient particles (CAPs). Fifteen healthy adult participants were exposed for 130 minutes to fine CAPs, coarse CAPs, or HEPA-filtered medical air (control) in randomized order with ≥2-week washout. Repetitive-element (Alu, long interspersed nuclear element-1 [LINE-1]) and candidate-gene (TLR4, IL-12, IL-6, iNOS) blood methylation, systolic and diastolic BP were measured pre- and postexposure. After adjustment for multiple comparisons, fine CAPs exposure lowered Alu methylation (β-standardized=-0.74, adjusted-P=0.03); coarse CAPs exposure lowered TLR4 methylation (β-standardized=-0.27, adjusted-P=0.04). Both fine and coarse CAPs determined significantly increased systolic BP (β=2.53 mm Hg, P=0.001; β=1.56 mm Hg, P=0.03, respectively) and nonsignificantly increased diastolic BP (β=0.98 mm Hg, P=0.12; β=0.82 mm Hg, P=0.11, respectively). Decreased Alu and TLR4 methylation was associated with higher postexposure DBP (β-standardized=0.41, P=0.04; and β-standardized=0.84, P=0.02; respectively). Decreased TLR4 methylation was associated with higher postexposure SBP (β-standardized=1.45, P=0.01). CONCLUSIONS Our findings provide novel evidence of effects of coarse PM on BP and confirm effects of fine PM. Our results provide the first experimental evidence of PM-induced DNA hypomethylation and its correlation to BP.
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Affiliation(s)
- Andrea Bellavia
- Department of Environmental Health, Harvard School of Public Health, Boston, MA 02215, USA
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Bellavia A, Urch B, Speck M, Brook RD, Scott JA, Albetti B, Behbod B, North M, Valeri L, Bertazzi PA, Silverman F, Gold D, A. Baccarelli A. DNA Hypomethylation, Ambient Particulate Matter, and Increased Blood Pressure: Findings From Controlled Human Exposure Experiments. J Am Heart Assoc 2013. [DOI: 10.1161/jaha.113.000212 10.1161/jaha.115.001981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Andrea Bellavia
- Department of Environmental Health, Harvard School of Public Health, Boston, MA
| | - Bruce Urch
- Gage Occupational and Environmental Health Unit, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Occupational and Environmental Health, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Mary Speck
- Gage Occupational and Environmental Health Unit, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Occupational and Environmental Health, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Robert D. Brook
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, MI
| | - Jeremy A. Scott
- Gage Occupational and Environmental Health Unit, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Occupational and Environmental Health, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Benedetta Albetti
- Department of Occupational and Environmental Health, Universita' degli Studi di Milano and Fondazione Ca' Granda Policlinico, Milan, Italy
| | - Behrooz Behbod
- Department of Environmental Health, Harvard School of Public Health, Boston, MA
| | - Michelle North
- Gage Occupational and Environmental Health Unit, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Occupational and Environmental Health, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Linda Valeri
- Department of Biostatistics, Harvard School of Public Health, Boston, MA
| | - Pier Alberto Bertazzi
- Department of Occupational and Environmental Health, Universita' degli Studi di Milano and Fondazione Ca' Granda Policlinico, Milan, Italy
| | - Frances Silverman
- Gage Occupational and Environmental Health Unit, St. Michael's Hospital, Toronto, Ontario, Canada
- Division of Occupational and Environmental Health, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Diane Gold
- Department of Environmental Health, Harvard School of Public Health, Boston, MA
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
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