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Cao C, Han Y, Hu H, He Y, Luo J. Non-linear relationship between pulse pressure and the risk of pre-diabetes: a secondary retrospective Chinese cohort study. BMJ Open 2024; 14:e080018. [PMID: 38521517 PMCID: PMC10961532 DOI: 10.1136/bmjopen-2023-080018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 03/01/2024] [Indexed: 03/25/2024] Open
Abstract
OBJECTIVE Previous research has shown that pulse pressure (PP) has a significant role in the start and development of type 2 diabetes mellitus. However, there is little proof that PP and pre-diabetes mellitus (Pre-DM) are related. Our study aimed to investigate the relationship between PP and incident pre-DM in a substantial cohort of Chinese participants. DESIGN The 'DATADRYAD' database (www.Datadryad.org) was used to retrieve the data for this secondary retrospective cohort analysis. PARTICIPANTS Data from 182 672 Chinese individuals who participated in the medical examination programme were recorded in this retrospective cohort study between 2010 and 2016 across 32 sites and 11 cities in China. SETTING PP assessed at baseline and incident pre-DM during follow-up were the target-independent and dependent variables. The association between PP and pre-DM was investigated using Cox proportional hazards regression. PRIMARY OUTCOME MEASURES The outcome was incident pre-DM. Impaired fasting glucose levels (fasting blood glucose between 5.6 and 6.9 mmol/L) were used to define pre-DM. RESULTS After controlling for confounding variables, PP was positively correlated with incident pre-DM among Chinese adults (HR 1.009, 95% CI 1.007 to 1.010). Additionally, at a PP inflection point of 29 mm Hg, a non-linear connection between the PP and incident pre-DM was discovered. Increased PP was an independent risk factor for developing pre-DM when PP was greater than 29 mm Hg. However, their association was not significant when PP was less than 29 mm Hg. According to subgroup analyses, females, never-smokers and non-obesity correlated more significantly with PP and pre-DM. CONCLUSION We discovered that higher PP independently correlated with pre-DM risk in this study of Chinese participants. The connection between PP and incident pre-DM was also non-linear. High PP levels were related to a higher risk of pre-DM when PP was above 29 mm Hg. ARTICLE FOCUS Our study investigated the relationship between PP and incident pre-DM in a secondary retrospective cohort of Chinese participants.
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Affiliation(s)
- Changchun Cao
- Department of Rehabilitation, Shenzhen Dapeng New District Nan'ao People's Hospital, Shenzhen, Guangdong, China
| | - Yong Han
- Department of Emergency, Shenzhen Second People's Hospital, Shenzhen, Guangdong Province, China
| | - Haofei Hu
- Department of Nephrology, Shenzhen University First Affiliated Hospital, Shenzhen, Guangdong, China
| | - Yongcheng He
- Department of Nephrology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan Province, China
- Department of Nephrology, Shenzhen Hengsheng Hospital, Shenzhen, Guangdong Province, China
| | - Jiao Luo
- Department of Rehabilitation, Shenzhen Dapeng New District Nan'ao People's Hospital, Dapeng New District, Guangdong Province, China
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Wang W, Li G, Ma J, Fan X, Lu J, Sun Q, Yao J, He Q. Microvascular rarefaction caused by the NOTCH signaling pathway is a key cause of TKI-apatinib-induced hypertension and cardiac damage. Front Pharmacol 2024; 15:1346905. [PMID: 38405666 PMCID: PMC10885812 DOI: 10.3389/fphar.2024.1346905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 01/30/2024] [Indexed: 02/27/2024] Open
Abstract
With the advancement of tumour-targeted therapy technology, the survival of cancer patients has continued to increase, and cardiovascular events have gradually become an important cause of death in cancer patients. This phenomenon occurs due to adverse cardiovascular reactions caused by the cardiovascular toxicity of antitumour therapy. Moreover, the increase in the proportion of elderly patients with cancer and cardiovascular diseases is due to the extension of life expectancy. Hypertension is the most common cardiovascular side effect of small molecule tyrosine kinase inhibitors (TKIs). The increase in blood pressure induced by TKIs and subsequent cardiovascular complications and events affect the survival and quality of life of patients and partly offset the benefits of antitumour therapy. Many studies have confirmed that in the pathogenesis of hypertension, arterioles and capillary thinness are involved in its occurrence and development. Our previous findings showing that apatinib causes microcirculation rarefaction of the superior mesenteric artery and impaired microvascular growth may inspire new therapeutic strategies for treating hypertension. Thus, by restoring microvascular development and branching patterns, total peripheral resistance and blood pressure are reduced. Therefore, exploring the key molecular targets of TKIs that inhibit the expression of angiogenic factors and elucidating the specific molecular mechanism involved are key scientific avenues for effectively promoting endothelial cell angiogenesis and achieving accurate repair of microcirculation injury in hypertension patients.
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Affiliation(s)
- WenJuan Wang
- Department of Cardiovascular Center, The First People’s Hospital of Huzhou City, Huzhou, China
| | - Guodong Li
- Department of Cardiovascular Center, The First People’s Hospital of Huzhou City, Huzhou, China
| | - Jie Ma
- Department of Hypertension Center, Lanzhou University Second Hospital, Lanzhou, China
| | - Xin Fan
- Department of Hypertension Center, Lanzhou University Second Hospital, Lanzhou, China
| | - Jianzhong Lu
- Department of Cardiovascular Center, The First People’s Hospital of Huzhou City, Huzhou, China
| | - Qiyin Sun
- Department of Cardiovascular Center, The First People’s Hospital of Huzhou City, Huzhou, China
| | - Jiafang Yao
- Department of Cardiovascular Center, The First People’s Hospital of Huzhou City, Huzhou, China
| | - Qingjian He
- Department of Breast and Thyroid Surgery, The First People’s Hospital of Huzhou City, Huzhou, China
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Oxidative Stress, Vascular Endothelium, and the Pathology of Neurodegeneration in Retina. Antioxidants (Basel) 2022; 11:antiox11030543. [PMID: 35326193 PMCID: PMC8944517 DOI: 10.3390/antiox11030543] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/07/2022] [Accepted: 03/10/2022] [Indexed: 02/06/2023] Open
Abstract
Oxidative stress (OS) is an imbalance between free radicals/ROS and antioxidants, which evokes a biological response and is an important risk factor for diseases, in both the cardiovascular system and central nervous system (CNS). The underlying mechanisms driving pathophysiological complications that arise from OS remain largely unclear. The vascular endothelium is emerging as a primary target of excessive glucocorticoid and catecholamine action. Endothelial dysfunction (ED) has been implicated to play a crucial role in the development of neurodegeneration in the CNS. The retina is known as an extension of the CNS. Stress and endothelium dysfunction are suspected to be interlinked and associated with neurodegenerative diseases in the retina as well. In this narrative review, we explore the role of OS-led ED in the retina by focusing on mechanistic links between OS and ED, ED in the pathophysiology of different retinal neurodegenerative conditions, and how a better understanding of the role of endothelial function could lead to new therapeutic approaches for neurodegenerative diseases in the retina.
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Astley C, Houacine C, Zaabalawi A, Wilkinson F, Lightfoot AP, Alexander Y, Whitehead D, Singh KK, Azzawi M. Nanostructured Lipid Carriers Deliver Resveratrol, Restoring Attenuated Dilation in Small Coronary Arteries, via the AMPK Pathway. Biomedicines 2021; 9:biomedicines9121852. [PMID: 34944670 PMCID: PMC8699041 DOI: 10.3390/biomedicines9121852] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 12/02/2021] [Indexed: 11/21/2022] Open
Abstract
Nanostructured lipid carriers (NLCs) are an emerging drug delivery platform for improved drug stability and the bioavailability of antihypertensive drugs and vasoprotective nutraceutical compounds, such as resveratrol (RV). The objective of this study was to ascertain NLCs’ potential to deliver RV and restore attenuated dilator function, using an ex vivo model of acute hypertension. Trimyristin–triolein NLCs were synthesized and loaded with RV. The uptake of RV-NLCs by human coronary artery endothelial cells (HCAECs) maintained their viability and reduced both mitochondrial and cytosolic superoxide levels. Acute pressure elevation in isolated coronary arteries significantly attenuated endothelial-dependent dilator responses, which were reversed following incubation in RV-NLCs, superoxide dismutase or apocynin (p < 0.0001). RV-NLCs demonstrated a five-fold increase in potency in comparison to RV solution. At elevated pressure, in the presence of RV-NLCs, incubation with Nω-nitro-l-arginine (L-NNA) or indomethacin resulted in a significant reduction in the restored dilator component (p < 0.0001), whereas apamin and TRAM-34 had no overall effect. Incubation with the adenosine monophosphate-activated protein kinase (AMPK) inhibitor dorsomorphin significantly attenuated dilator responses (p < 0.001), whereas the SIRT-1 inhibitor EX-527 had no effect. RV-NLCs improved the impaired endothelial-dependent dilation of small coronary arteries, following acute pressure elevation, via NO and downstream COX elements, mediated by AMPK. We suggest that RV-NLCs are an effective delivery modality for improved potency and sustained drug release into the vasculature. Our findings have important implications for the future design and implementation of antihypertensive treatment strategies.
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Affiliation(s)
- Cai Astley
- Centre for Bioscience, Department of Life Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK; (C.A.); (A.Z.); (F.W.); (A.P.L.); (Y.A.)
| | - Chahinez Houacine
- School of Pharmacy and Biomedical Sciences, Faculty of Clinical and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, UK;
| | - Azziza Zaabalawi
- Centre for Bioscience, Department of Life Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK; (C.A.); (A.Z.); (F.W.); (A.P.L.); (Y.A.)
| | - Fiona Wilkinson
- Centre for Bioscience, Department of Life Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK; (C.A.); (A.Z.); (F.W.); (A.P.L.); (Y.A.)
| | - Adam P. Lightfoot
- Centre for Bioscience, Department of Life Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK; (C.A.); (A.Z.); (F.W.); (A.P.L.); (Y.A.)
| | - Yvonne Alexander
- Centre for Bioscience, Department of Life Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK; (C.A.); (A.Z.); (F.W.); (A.P.L.); (Y.A.)
| | - Debra Whitehead
- Department of Natural Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK;
| | - Kamalinder K. Singh
- School of Pharmacy and Biomedical Sciences, Faculty of Clinical and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, UK;
- Correspondence: (K.K.S.); (M.A.)
| | - May Azzawi
- Centre for Bioscience, Department of Life Sciences, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK; (C.A.); (A.Z.); (F.W.); (A.P.L.); (Y.A.)
- Correspondence: (K.K.S.); (M.A.)
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Ungvari Z, Toth P, Tarantini S, Prodan CI, Sorond F, Merkely B, Csiszar A. Hypertension-induced cognitive impairment: from pathophysiology to public health. Nat Rev Nephrol 2021; 17:639-654. [PMID: 34127835 PMCID: PMC8202227 DOI: 10.1038/s41581-021-00430-6] [Citation(s) in RCA: 169] [Impact Index Per Article: 56.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2021] [Indexed: 02/06/2023]
Abstract
Hypertension affects two-thirds of people aged >60 years and significantly increases the risk of both vascular cognitive impairment and Alzheimer's disease. Hypertension compromises the structural and functional integrity of the cerebral microcirculation, promoting microvascular rarefaction, cerebromicrovascular endothelial dysfunction and neurovascular uncoupling, which impair cerebral blood supply. In addition, hypertension disrupts the blood-brain barrier, promoting neuroinflammation and exacerbation of amyloid pathologies. Ageing is characterized by multifaceted homeostatic dysfunction and impaired cellular stress resilience, which exacerbate the deleterious cerebromicrovascular effects of hypertension. Neuroradiological markers of hypertension-induced cerebral small vessel disease include white matter hyperintensities, lacunar infarcts and microhaemorrhages, all of which are associated with cognitive decline. Use of pharmaceutical and lifestyle interventions that reduce blood pressure, in combination with treatments that promote microvascular health, have the potential to prevent or delay the pathogenesis of vascular cognitive impairment and Alzheimer's disease in patients with hypertension.
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Affiliation(s)
- Zoltan Ungvari
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- Department of Health Promotion Sciences, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Peter Toth
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- Department of Neurosurgery, Medical School, University of Pecs, Pecs, Hungary
| | - Stefano Tarantini
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- Department of Health Promotion Sciences, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Calin I Prodan
- Department of Neurology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Veterans Affairs Medical Center, Oklahoma City, OK, USA
| | - Farzaneh Sorond
- Department of Neurology, Division of Stroke and Neurocritical Care, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Bela Merkely
- Heart and Vascular Center, Semmelweis University, Budapest, Hungary
| | - Anna Csiszar
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Institute of Clinical Experimental Research, Semmelweis University, Budapest, Hungary.
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Tickle PG, Hendrickse PW, Weightman A, Nazir MH, Degens H, Egginton S. Impaired skeletal muscle fatigue resistance during cardiac hypertrophy is prevented by functional overload- or exercise-induced functional capillarity. J Physiol 2021; 599:3715-3733. [PMID: 34107075 DOI: 10.1113/jp281377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 06/04/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Capillary rarefaction is hypothesized to contribute to impaired exercise tolerance in cardiovascular disease, but it remains a poorly exploited therapeutic target for improving skeletal muscle performance. Using an abdominal aortic coarctation rat model of compensatory cardiac hypertrophy, we determine the efficacy of aerobic exercise for the prevention of, and mechanical overload for, restoration of hindlimb muscle fatigue resistance and microvascular impairment in the early stages of heart disease. Impaired muscle fatigue resistance was found after development of cardiac hypertrophy, but this impairment was prevented by low-intensity aerobic exercise and recovered after mechanical stretch due to muscle overload. Changes in muscle fatigue resistance were closely related to functional (i.e. perfused) microvascular density, independent of arterial blood flow, emphasizing the critical importance of optimal capillary diffusion for skeletal muscle function. Pro-angiogenic therapies are an important tool for improving skeletal muscle function in the incipient stages of heart disease. ABSTRACT Microvascular rarefaction may contribute to declining skeletal muscle performance in cardiac and vascular diseases. It remains uncertain to what extent microvascular rarefaction occurs in the earliest stages of these conditions, if impaired blood flow is an aggravating factor and whether angiogenesis restores muscle performance. To investigate this, the effects of aerobic exercise (voluntary wheel running) and functional muscle overload on the performance, femoral blood flow (FBF) and microvascular perfusion of the extensor digitorum longus (EDL) were determined in a chronic rat model of compensatory cardiac hypertrophy (CCH, induced by surgically imposed abdominal aortic coarctation). CCH was associated with hypertension (P = 0.001 vs. Control) and increased relative heart mass (P < 0.001). Immediately upon placing the aortic band (i.e. before development of CCH), post-fatigue test FBF was reduced (P < 0.003), coinciding with attenuated fatigue resistance (P = 0.039) indicating an acute arterial perfusion constraint on muscle performance. While FBF was normalized during CCH in chronic groups (P > 0.05) fatigue resistance remained reduced (P = 0.039) and was associated with reduced (P = 0.009) functional capillarity after development of CCH without intervention, indicating a microvascular limitation to muscle performance. Normalization of functional capillarity after aerobic exercise (P = 0.065) and overload (P = 0.329) in CCH coincided with restoration to control levels of muscle fatigue resistance (P > 0.999), although overload-induced EDL hypertrophy (P = 0.027) and wheel-running velocity and duration (both P < 0.05) were attenuated after aortic banding. These data show that reductions in skeletal muscle performance during CCH can be countered by improving functional capillarity, providing a therapeutic target to improve skeletal muscle function in chronic diseases.
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Affiliation(s)
- Peter G Tickle
- School of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Paul W Hendrickse
- Department of Life Sciences, Research Centre for Musculoskeletal Science & Sports Medicine, Manchester Metropolitan University, Manchester, UK.,Institute of Sport Science and Innovations, Lithuanian Sports University, Kaunas, Lithuania
| | - Andrew Weightman
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester, UK
| | - M Hakam Nazir
- School of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Hans Degens
- Department of Life Sciences, Research Centre for Musculoskeletal Science & Sports Medicine, Manchester Metropolitan University, Manchester, UK.,Institute of Sport Science and Innovations, Lithuanian Sports University, Kaunas, Lithuania
| | - Stuart Egginton
- School of Biomedical Sciences, University of Leeds, Leeds, UK
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Wu Y, Han X, Gao J, Wang Y, Zhu C, Huang Z, Xing A, Chen S, Ma Y, Zheng M, Liu Q, Tian Y, Wu S. Individual and combined contributions of age-specific and sex-specific pulse pressure and brachial-ankle pulse wave velocity to the risk of new-onset diabetes mellitus. BMJ Open Diabetes Res Care 2021; 9:9/1/e001942. [PMID: 34155045 PMCID: PMC8217932 DOI: 10.1136/bmjdrc-2020-001942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 04/19/2021] [Accepted: 04/25/2021] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION We aimed to investigate the individual and combined effects of age-specific and sex-specific pulse pressure (PP) and brachial-ankle pulse wave velocity (baPWV) on the incidence of new-onset diabetes mellitus. RESEARCH DESIGN AND METHODS Participants in the Kailuan study cohort who were ≥20 years old, participated in follow-up assessments and underwent baPWV measurements in 2010-2011, 2012-2013, and 2014-2015 were studied. The participants were allocated to four groups according to their PP and baPWV status, each categorized as high or normal, according to age-specific and sex-specific median values. Cox proportional hazards models were used to explore the individual and combined effects of PP and baPWV on the incidence of diabetes mellitus. RESULTS There were 18 619 participants who were followed for 4.27±1.91 years. A total of 877 new cases of diabetes were identified, and the incidence density was 11.03/1000 per year. Using the normal PP and normal baPWV group as the reference group, the multivariable-adjusted HRs and 95% CIs for diabetes mellitus in the high PP and high baPWV groups were 1.08 (0.93 to 1.25) and 1.64 (1.41 to 1.90), respectively. Compared with the normal PP/baPWV group, the HR and 95% CI for diabetes in the normal PP/high baPWV, the high PP/normal baPWV, and high PP/baPWV groups were 1.66 (1.35 to 2.05), 1.09 (0.86 to 1.37), and 1.74 (1.43 to 2.13), respectively. CONCLUSIONS High baPWV was independently associated with a higher risk of diabetes mellitus, and individuals with both high baPWV and high PP were at a still higher risk of diabetes mellitus.
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Affiliation(s)
- Yuntao Wu
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Xu Han
- Graduate School, North China University of Science and Technology, Tangshan, China
| | - Jingli Gao
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Yanxiu Wang
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Chenrui Zhu
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Zhe Huang
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Aijun Xing
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Shuohua Chen
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Yihan Ma
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Mengyi Zheng
- Graduate School, North China University of Science and Technology, Tangshan, China
| | - Qian Liu
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
| | - Yaohua Tian
- Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shouling Wu
- Department of Cardiology, Kailuan General Hospital, North China University of Science and Technology, Tangshan, China
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Abstract
The microcirculation maintains tissue homeostasis through local regulation of blood flow and oxygen delivery. Perturbations in microvascular function are characteristic of several diseases and may be early indicators of pathological changes in the cardiovascular system and in parenchymal tissue function. These changes are often mediated by various reactive oxygen species and linked to disruptions in pathways such as vasodilation or angiogenesis. This overview compiles recent advances relating to redox regulation of the microcirculation by adopting both cellular and functional perspectives. Findings from a variety of vascular beds and models are integrated to describe common effects of different reactive species on microvascular function. Gaps in understanding and areas for further research are outlined. © 2020 American Physiological Society. Compr Physiol 10:229-260, 2020.
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Affiliation(s)
- Andrew O Kadlec
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Medical Scientist Training Program, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - David D Gutterman
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Department of Medicine-Division of Cardiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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Lipecz A, Miller L, Kovacs I, Czakó C, Csipo T, Baffi J, Csiszar A, Tarantini S, Ungvari Z, Yabluchanskiy A, Conley S. Microvascular contributions to age-related macular degeneration (AMD): from mechanisms of choriocapillaris aging to novel interventions. GeroScience 2019; 41:813-845. [PMID: 31797238 PMCID: PMC6925092 DOI: 10.1007/s11357-019-00138-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 11/12/2019] [Indexed: 12/13/2022] Open
Abstract
Aging of the microcirculatory network plays a central role in the pathogenesis of a wide range of age-related diseases, from heart failure to Alzheimer's disease. In the eye, changes in the choroid and choroidal microcirculation (choriocapillaris) also occur with age, and these changes can play a critical role in the pathogenesis of age-related macular degeneration (AMD). In order to develop novel treatments for amelioration of choriocapillaris aging and prevention of AMD, it is essential to understand the cellular and functional changes that occur in the choroid and choriocapillaris during aging. In this review, recent advances in in vivo analysis of choroidal structure and function in AMD patients and patients at risk for AMD are discussed. The pathophysiological roles of fundamental cellular and molecular mechanisms of aging including oxidative stress, mitochondrial dysfunction, and impaired resistance to molecular stressors in the choriocapillaris are also considered in terms of their contribution to the pathogenesis of AMD. The pathogenic roles of cardiovascular risk factors that exacerbate microvascular aging processes, such as smoking, hypertension, and obesity as they relate to AMD and choroid and choriocapillaris changes in patients with these cardiovascular risk factors, are also discussed. Finally, future directions and opportunities to develop novel interventions to prevent/delay AMD by targeting fundamental cellular and molecular aging processes are presented.
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Affiliation(s)
- Agnes Lipecz
- Translational Geroscience Laboratory, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Ophthalmology, Josa Andras Hospital, Nyiregyhaza, Hungary
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Lauren Miller
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 940 Stanton L. Young Blvd. BMSB553, Oklahoma City, OK, 73104, USA
| | - Illes Kovacs
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
- Department of Ophthalmology, Weill Cornell Medical College, New York City, NY, USA
| | - Cecília Czakó
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Tamas Csipo
- Translational Geroscience Laboratory, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- International Training Program in Geroscience, Division of Clinical Physiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Judit Baffi
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Anna Csiszar
- Translational Geroscience Laboratory, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- International Training Program in Geroscience, Theoretical Medicine Doctoral School, University of Szeged, Szeged, Hungary
| | - Stefano Tarantini
- Translational Geroscience Laboratory, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- International Training Program in Geroscience, Theoretical Medicine Doctoral School, University of Szeged, Szeged, Hungary
| | - Zoltan Ungvari
- Translational Geroscience Laboratory, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine/Department of Public Health, Semmelweis University, Budapest, Hungary
- International Training Program in Geroscience, Theoretical Medicine Doctoral School, University of Szeged, Szeged, Hungary
- Department of Health Promotion Sciences, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Andriy Yabluchanskiy
- Translational Geroscience Laboratory, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Shannon Conley
- Vascular Cognitive Impairment and Neurodegeneration Program, Center for Geroscience and Healthy Brain Aging/Reynolds Oklahoma Center on Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 940 Stanton L. Young Blvd. BMSB553, Oklahoma City, OK, 73104, USA.
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10
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Ran K, Yang Z, Zhao Y, Wang X. Transmural pressure drives proliferation of human arterial smooth muscle cells via mechanism associated with NADPH oxidase and Survivin. Microvasc Res 2019; 126:103905. [DOI: 10.1016/j.mvr.2019.103905] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/12/2019] [Accepted: 07/05/2019] [Indexed: 10/26/2022]
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11
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A Prior High-Intensity Exercise Bout Attenuates the Vascular Dysfunction Resulting From a Prolonged Sedentary Bout. J Phys Act Health 2019; 16:916-924. [DOI: 10.1123/jpah.2018-0568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 06/04/2019] [Accepted: 07/14/2019] [Indexed: 11/18/2022]
Abstract
Background: This study sought to determine the impact of an acute prior bout of high-intensity interval aerobic exercise on attenuating the vascular dysfunction associated with a prolonged sedentary bout. Methods: Ten young (24 ± 1 y) healthy males completed two 3-hour sessions of prolonged sitting with (SIT-EX) and without (SIT) a high-intensity interval aerobic exercise session performed immediately prior. Prior to and 3 hours into the sitting bout, leg vascular function was assessed with the passive leg movement technique, and blood samples were obtained from the lower limb to evaluate changes in oxidative stress (malondialdehyde and superoxide dismutase) and inflammation (interleukin-6). Results: No presitting differences in leg vascular function (assessed via passive leg movement technique-induced hyperemia) were revealed between conditions. After 3 hours of prolonged sitting, leg vascular function was significantly reduced in the SIT condition, but unchanged in the SIT-EX. Lower limb blood samples revealed no alterations in oxidative stress, antioxidant capacity, or inflammation in either condition. Conclusions: This study revealed that lower limb vascular dysfunction was significantly attenuated by an acute presitting bout of high-intensity interval aerobic exercise. Further analysis of lower limb blood samples revealed no changes in circulating oxidative stress or inflammation in either condition.
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12
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Garten RS, Hogwood AC, Weggen JB, Fralin RC, LaRosa K, Lee D, Michael A, Scott M. Aerobic training status does not attenuate prolonged sitting-induced lower limb vascular dysfunction. Appl Physiol Nutr Metab 2018; 44:425-433. [PMID: 30257099 DOI: 10.1139/apnm-2018-0420] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This study examined if the degree of aerobic training protects against the lower limb vascular dysfunction associated with a prolonged sitting bout. Ten young, aerobically trained (AT) and 10 young, untrained (UT) individuals completed a prolonged (3 h) sitting bout. Leg vascular function was measured prior to and at 1.5 and 3 h into the prolonged sitting bout using the passive leg movement (PLM) technique. PLM-induced hyperemia was significantly reduced from baseline at 1.5 and 3 h into the prolonged sitting bout in both groups when evaluated as peak change in leg blood flow from baseline (Δ LBF) (UT: 956 ± 140, 586 ± 80, and 599 ± 96 mL·min-1 at baseline, 1.5 h, and 3 h, respectively; AT: 955 ± 183, 789 ± 193, and 712 ± 131 mL·min-1 at baseline, 1.5 h, and 3 h, respectively) and LBF area under the curve (UT: 283 ± 73, 134 ± 31, and 164 ± 42 mL·min-1 at baseline, 1.5 h, and 3 h, respectively; AT: 336 ± 86, 242 ± 86, and 245 ± 73 mL·min-1 at baseline, 1.5 h, and 3 h, respectively), but no significant differences between groups were revealed. No significant correlations were observed when examining the relationship between maximal oxygen uptake (relative and absolute) and reductions in leg vascular function at 1.5 and 3 h into the prolonged sitting bout. This study revealed that aerobic training did not provide a protective effect against prolonged sitting-induced lower limb vascular dysfunction and further highlights the importance of reducing excessive sitting in all populations.
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Affiliation(s)
- Ryan S Garten
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Austin C Hogwood
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Jennifer B Weggen
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - R Carson Fralin
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Kathryn LaRosa
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - David Lee
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Austin Michael
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Matthew Scott
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
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13
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Junqueira CLC, Magalhães MEC, Brandão AA, Ferreira E, Cyrino FZGA, Maranhão PA, Souza MDGC, Bottino DA, Bouskela E. Microcirculation and biomarkers in patients with resistant or mild-to-moderate hypertension: a cross-sectional study. Hypertens Res 2018; 41:515-523. [DOI: 10.1038/s41440-018-0043-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 11/06/2017] [Accepted: 11/30/2017] [Indexed: 01/04/2023]
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14
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Togliatto G, Lombardo G, Brizzi MF. The Future Challenge of Reactive Oxygen Species (ROS) in Hypertension: From Bench to Bed Side. Int J Mol Sci 2017; 18:ijms18091988. [PMID: 28914782 PMCID: PMC5618637 DOI: 10.3390/ijms18091988] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 09/07/2017] [Accepted: 09/13/2017] [Indexed: 02/07/2023] Open
Abstract
Reactive oxygen species (ROS) act as signaling molecules that control physiological processes, including cell adaptation to stress. Redox signaling via ROS has quite recently become the focus of much attention in numerous pathological contexts, including neurodegenerative diseases, kidney and cardiovascular disease. Imbalance in ROS formation and degradation has also been implicated in essential hypertension. Essential hypertension is characterized by multiple genetic and environmental factors which do not completely explain its associated risk factors. Thereby, even if advances in therapy have led to a significant reduction in hypertension-associated complications, to interfere with the unbalance of redox signals might represent an additional therapeutic challenge. The decrease of nitric oxide (NO) levels, the antioxidant activity commonly found in preclinical models of hypertension and the ability of antioxidant approaches to reduce ROS levels have spurred clinicians to investigate the contribution of ROS in humans. Indeed, particular effort has recently been devoted to understanding how redox signaling may contribute to vascular pathobiology in human hypertension. However, although biomarkers of oxidative stress have been found to positively correlate with blood pressure in preclinical model of hypertension, human data are less convincing. We herein provide an overview of the most relevant mechanisms via which oxidative stress might contribute to the pathophysiology of essential hypertension. Moreover, alternative approaches, which are directed towards improving antioxidant machinery and/or interfering with ROS production, are also discussed.
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Affiliation(s)
- Gabriele Togliatto
- Department of Medical Sciences, University of Torino, 10126 Torino, Italy.
| | - Giusy Lombardo
- Department of Medical Sciences, University of Torino, 10126 Torino, Italy.
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15
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Ungvari Z, Tarantini S, Kirkpatrick AC, Csiszar A, Prodan CI. Cerebral microhemorrhages: mechanisms, consequences, and prevention. Am J Physiol Heart Circ Physiol 2017; 312:H1128-H1143. [PMID: 28314762 PMCID: PMC5495931 DOI: 10.1152/ajpheart.00780.2016] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/22/2017] [Accepted: 03/09/2017] [Indexed: 12/20/2022]
Abstract
The increasing prevalence of multifocal cerebral microhemorrhages (CMHs, also known as "cerebral microbleeds") is a significant, newly recognized problem in the aging population of the Western world. CMHs are associated with rupture of small intracerebral vessels and are thought to progressively impair neuronal function, potentially contributing to cognitive decline, geriatric psychiatric syndromes, and gait disorders. Clinical studies show that aging and hypertension significantly increase prevalence of CMHs. CMHs are also now recognized by the National Institutes of Health as a major factor in Alzheimer's disease pathology. Moreover, the presence of CMHs is an independent risk factor for subsequent larger intracerebral hemorrhages. In this article, we review the epidemiology, detection, risk factors, clinical significance, and pathogenesis of CMHs. The potential age-related cellular mechanisms underlying the development of CMHs are discussed, with a focus on the structural determinants of microvascular fragility, age-related alterations in cerebrovascular adaptation to hypertension, the role of oxidative stress and matrix metalloproteinase activation, and the deleterious effects of arterial stiffening, increased pulse pressure, and impaired myogenic autoregulatory protection on the brain microvasculature. Finally, we examine potential treatments for the prevention of CMHs based on the proposed model of aging- and hypertension-dependent activation of the reactive oxygen species-matrix metalloproteinases axis, and we discuss critical questions to be addressed by future studies.
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Affiliation(s)
- Zoltan Ungvari
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; .,Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Stefano Tarantini
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.,Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Angelia C Kirkpatrick
- Veterans Affairs Medical Center, Oklahoma City, Oklahoma.,Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and
| | - Anna Csiszar
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.,Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Calin I Prodan
- Department of Neurology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
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16
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Varga ZV, Matyas C, Paloczi J, Pacher P. Alcohol Misuse and Kidney Injury: Epidemiological Evidence and Potential Mechanisms. Alcohol Res 2017; 38:283-288. [PMID: 28988579 PMCID: PMC5513691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Chronic alcohol consumption is a well-known risk factor for tissue injury. The link between alcohol use disorder (AUD) and kidney injury is intriguing but controversial, and the molecular mechanisms by which alcohol may damage the kidneys are poorly understood. Epidemiological studies attempting to link AUD and kidney disease are, to date, inconclusive, and there is little experimental evidence directly linking alcohol consumption to kidney injury. However, studies conducted primarily in other organs and tissues suggest several possible mechanisms by which alcohol may promote kidney dysfunction. One possible mechanism is oxidative stress resulting from increased production of reactive oxygen species, which leads to an excessive amount of free radicals, which in turn trigger tissue injury and increase inflammation. In addition, AUD's effect on other major organs (liver, heart, intestines, and skeletal muscle) appears to promote unfavorable pathological processes that are harmful to the kidneys. Notably, these mechanisms have not yet been validated experimentally in the kidney. Additional research is needed to clarify if alcohol does indeed promote kidney injury and the mechanisms by which alcohol-induced kidney injury may occur.
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17
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BERNÁTOVÁ I, BALIŠ P, GOGA R, BEHULIAK M, ZICHA J, SEKAJ I. Lack of Reactive Oxygen Species Deteriorates Blood Pressure Regulation in Acute Stress. Physiol Res 2016; 65:S381-S390. [DOI: 10.33549/physiolres.933433] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
This study investigated the contribution of reactive oxygen species (ROS) to blood pressure regulation in conscious adult male Wistar rats exposed to acute stress. Role of ROS was investigated in rats with temporally impaired principal blood pressure regulation systems using ganglionic blocker pentolinium (P, 5 mg/kg), angiotensin converting enzyme inhibitor captopril (C, 10 mg/kg), nitric oxide synthase inhibitor L-NAME (L, 30 mg/kg) and superoxide dismutase mimeticum tempol (T, 25 mg/kg). Mean arterial pressure (MAP) was measured by the carotid artery catheter and inhibitors were administered intravenously. MAP was disturbed by a 3-s air jet, which increased MAP by 35.2±3.0 % vs. basal MAP after the first exposure. Air jet increased MAP in captopril- and tempol-treated rats similarly as observed in saline-treated rats. In pentolinium-treated rats stress significantly decreased MAP vs. pre-stress value. In L-NAME-treated rats stress failed to affect MAP significantly. Treatment of rats with P+L+C resulted in stress-induced MAP decrease by 17.3±1.3 % vs. pre-stress value and settling time (20.1±4.2 s). In P+L+C+T-treated rats stress led to maximal MAP decrease by 26.4±2.2 % (p<0.005 vs. P+L+C) and prolongation of settling time to 32.6±3.3 s (p<0.05 vs. P+L+C). Area under the MAP curve was significantly smaller in P+L+C-treated rats compared to P+L+C+T-treated ones (167±43 vs. 433±69 a.u., p<0.008). In conclusion, in rats with temporally impaired blood pressure regulation, the lack of ROS resulted in greater stress-induced MAP alterations and prolongation of time required to reach new post-stress steady state.
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Affiliation(s)
- I. BERNÁTOVÁ
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovak Republic
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18
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Rugale C, Cordaillat M, Mimran A, Jover B. Prevention and Reversal by Enalapril of Target Organ Damage in Angiotensin II Hypertension. J Renin Angiotensin Aldosterone Syst 2016; 6:154-60. [PMID: 16525947 DOI: 10.3317/jraas.2005.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Angiotensin-converting enzyme inhibitors (ACE-Is) prevent target organ damage in several models of hypertension. The aim of this study was to assess the influence of the ACE-I enalapril (10 mg/kg-1per day, gavage) on the cardiovascular alterations and production of free radicals induced by chronic infusion of angiotensin II (Ang II, 200 ng/kg-1per minute, SC) in Sprague-Dawley rats. Enalapril was given concomitantly for the 10 days of Ang II infusion (prevention) or from day 10 to 17 of Ang II infusion (intervention). The influence of the NADPH oxidase inhibitor apocynin (600 mg/L-1in drinking water) was evaluated. mg/L-lin drinking water) was evaluated. Enalapril and apocynin had no effect on hypertension in the prevention and intervention studies. Enalapril prevented the increase in heart weight index (HWI), carotid cross-sectional area (CSA) and albuminuria induced by Ang II. Enalapril reduced HWI and albuminuria whereas CSA I was not affected in the intervention study. Apocynin had effects comparable to enalapril. Both enalapril and apocynin reduced the overproduction of superoxide anion by the left ventricle and rise in advanced oxidation protein products induced by C Ang II. Therefore, the antioxidant but not the antihypertensive effect of enalapril may participate in the prevention and treatment of the Ang II-induced cardiovascular and renal alterations.
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Affiliation(s)
- Caroline Rugale
- Groupe Rein et Hypertension, Université Montpellier I, Montpellier, France
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19
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Springo Z, Tarantini S, Toth P, Tucsek Z, Koller A, Sonntag WE, Csiszar A, Ungvari Z. Aging Exacerbates Pressure-Induced Mitochondrial Oxidative Stress in Mouse Cerebral Arteries. J Gerontol A Biol Sci Med Sci 2015; 70:1355-9. [PMID: 25631392 PMCID: PMC4612385 DOI: 10.1093/gerona/glu244] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 12/08/2014] [Indexed: 12/21/2022] Open
Abstract
Epidemiological studies demonstrate that in addition to the increased prevalence of hypertension in old patients, the deleterious cerebrovascular effects of hypertension (including atherosclerosis, stroke, and vascular cognitive impairment) are also exacerbated in elderly individuals. The cellular mechanisms by which aging and hypertension interact to promote cerebrovascular pathologies are not well understood. To test the hypothesis that aging exacerbates high pressure-induced mitochondrial oxidative stress, we exposed isolated segments of the middle cerebral arteries of young (3 months) and aged (24 months) C57BL/6 mice to 60 or 140 mmHg intraluminal pressure and assessed changes in mitochondrial reactive oxygen species production using a mitochondria-targeted redox-sensitive fluorescent indicator dye (MitoSox) by confocal microscopy. Perinuclear MitoSox fluorescence was significantly stronger in high pressure-exposed middle cerebral arteries compared with middle cerebral arteries of the same animals exposed to 60 mmHg, indicating that high pressure increases mitochondrial reactive oxygen species production in the smooth muscle cells of cerebral arteries. Comparison of young and aged middle cerebral arteries showed that aging exacerbates high pressure-induced mitochondrial reactive oxygen species production in cerebral arteries. We propose that increased mechanosensitive mitochondrial oxidative stress may potentially exacerbate cerebrovascular injury and vascular inflammation in aging.
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Affiliation(s)
- Zsolt Springo
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. Department of Pathophysiology and Gerontology, Medical School and Szentágothai Research Center, University of Pecs, Hungary
| | - Stefano Tarantini
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center
| | - Peter Toth
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center
| | - Zsuzsanna Tucsek
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center
| | - Akos Koller
- Department of Pathophysiology and Gerontology, Medical School and Szentágothai Research Center, University of Pecs, Hungary
| | - William E Sonntag
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. The Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center
| | - Anna Csiszar
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. Department of Pathophysiology and Gerontology, Medical School and Szentágothai Research Center, University of Pecs, Hungary. The Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center
| | - Zoltan Ungvari
- Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center. Department of Pathophysiology and Gerontology, Medical School and Szentágothai Research Center, University of Pecs, Hungary. The Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center.
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20
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Effect of Selenium Supplementation on Redox Status of the Aortic Wall in Young Spontaneously Hypertensive Rats. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:609053. [PMID: 26473024 PMCID: PMC4592724 DOI: 10.1155/2015/609053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/23/2015] [Accepted: 03/10/2015] [Indexed: 01/18/2023]
Abstract
Selenium (Se) is an exogenous antioxidant that performs its function via the expression of selenoproteins. The aim of this study was to explore the effect of varying Se intake on the redox status of the aortic wall in young spontaneously hypertensive rats (SHR). Sixteen male Wistar Kyoto (WKY) rats and nineteen male SHR, 16-week-old, were tested after being given diets with different Se content for eight weeks. They were divided into 4 groups: control groups of WKY NSe and SHR NSe on an adequate Se diet and groups of WKY HSe and SHR HSe that received Se supplementation. The Se nutritional status was assessed by measuring whole blood glutathione peroxidase-1 (GPx-1) activity. Serum concentration of lipid hydroperoxides and serum level of antibodies against advanced glycation end products (anti-AGEs abs) were determined. Expression of GPx-1 and endothelial nitric oxide synthase (eNOS) were examined in aortic wall. Se supplementation significantly increased GPx-1 activity of whole blood and in the aortas of WKY and SHR. Decreased lipid peroxidation level, eNOS-3 expression in the aortic wall, and serum level of anti-AGEs abs were found in SHR HSe compared with SHR NSe.
In conclusion, Se supplementation improved the redox status of the aortic wall in young SHR.
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21
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Husain K, Hernandez W, Ansari RA, Ferder L. Inflammation, oxidative stress and renin angiotensin system in atherosclerosis. World J Biol Chem 2015; 6:209-217. [PMID: 26322175 PMCID: PMC4549761 DOI: 10.4331/wjbc.v6.i3.209] [Citation(s) in RCA: 225] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 05/15/2015] [Accepted: 06/19/2015] [Indexed: 02/05/2023] Open
Abstract
Atherosclerosis is a chronic inflammatory disease associated with cardiovascular dysfunction including myocardial infarction, unstable angina, sudden cardiac death, stroke and peripheral thromboses. It has been predicted that atherosclerosis will be the primary cause of death in the world by 2020. Atherogenesis is initiated by endothelial injury due to oxidative stress associated with cardiovascular risk factors including diabetes mellitus, hypertension, cigarette smoking, dyslipidemia, obesity, and metabolic syndrome. The impairment of the endothelium associated with cardiovascular risk factors creates an imbalance between vasodilating and vasoconstricting factors, in particular, an increase in angiotensin II (Ang II) and a decrease in nitric oxide. The renin-angiotensin system (RAS), and its primary mediator Ang II, also have a direct influence on the progression of the atherosclerotic process via effects on endothelial function, inflammation, fibrinolytic balance, and plaque stability. Anti-inflammatory agents [statins, secretory phospholipase A2 inhibitor, lipoprotein-associated phospholipase A2 inhibitor, 5-lipoxygenase activating protein, chemokine motif ligand-2, C-C chemokine motif receptor 2 pathway inhibitors, methotrexate, IL-1 pathway inhibitor and RAS inhibitors (angiotensin-converting enzyme inhibitors)], Ang II receptor blockers and ranin inhibitors may slow inflammatory processes and disease progression. Several studies in human using anti-inflammatory agents and RAS inhibitors revealed vascular benefits and reduced progression of coronary atherosclerosis in patients with stable angina pectoris; decreased vascular inflammatory markers, improved common carotid intima-media thickness and plaque volume in patients with diagnosed atherosclerosis. Recent preclinical studies have demonstrated therapeutic efficacy of vitamin D analogs paricalcitol in ApoE-deficient atherosclerotic mice.
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Husain K, Suarez E, Isidro A, Hernandez W, Ferder L. Effect of paricalcitol and enalapril on renal inflammation/oxidative stress in atherosclerosis. World J Biol Chem 2015; 6:240-248. [PMID: 26322179 PMCID: PMC4549765 DOI: 10.4331/wjbc.v6.i3.240] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 03/25/2015] [Accepted: 06/11/2015] [Indexed: 02/05/2023] Open
Abstract
AIM: To investigate the protective effect of paricalcitol and enalapril on renal inflammation and oxidative stress in ApoE-knock out mice.
METHODS: Animals treated for 4 mo as group (1) ApoE-knock out plus vehicle, group (2) ApoE-knock out plus paricalcitol (200 ng thrice a week), (3) ApoE-knock out plus enalapril (30 mg/L), (4) ApoE-knock out plus paricalcitol plus enalapril and (5) normal. Blood pressure (BP) was recorded using tail cuff method. The kidneys were isolated for biochemical assays using spectrophotometer and Western blot analyses.
RESULTS: ApoE-deficient mice developed high BP (127 ± 3 mmHg) and it was ameliorated by enalapril and enalapril plus paricalcitol treatments but not with paricalcitol alone. Renal malondialdehyde concentrations, p22phox, manganese-superoxide dismutase, inducible nitric oxide synthase (NOS), monocyte chemoattractant protein-1, tumor necrosis factor-alpha and transforming growth factor-β1 levels significantly elevated but reduced glutathione, CuZn-SOD and eNOS levels significantly depleted in ApoE-knock out animals compared to normal. Administration of paricalcitol, enalapril and combined together ameliorated the renal inflammation and oxidative stress in ApoE-knock out animals.
CONCLUSION: Paricalcitol and enalapril combo treatment ameliorates renal inflammation as well as oxidative stress in atherosclerotic animals.
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23
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Toth P, Csiszar A, Sosnowska D, Tucsek Z, Cseplo P, Springo Z, Tarantini S, Sonntag WE, Ungvari Z, Koller A. Treatment with the cytochrome P450 ω-hydroxylase inhibitor HET0016 attenuates cerebrovascular inflammation, oxidative stress and improves vasomotor function in spontaneously hypertensive rats. Br J Pharmacol 2015. [PMID: 23194285 DOI: 10.1111/bph.12079] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Hypertension increases cerebrovascular oxidative stress and inflammation and impairs vasomotor function. These pathological alterations lead to dysregulation of cerebral blood flow and exacerbate atherogenesis, increasing the morbidity of ischaemic cerebrovascular diseases and promoting vascular cognitive impairment. We aimed to test the hypothesis that increased production of the arachidonic acid metabolite 20-hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE) contributes to hypertension-induced cerebrovascular alterations. EXPERIMENTAL APPROACH We treated male spontaneously hypertensive rats (SHR) with HET0016 (N-hydroxy-N'-(4-butyl-2-methylphenyl)-formamidine), an inhibitor of 20-HETE synthesis. In middle cerebral arteries (MCAs) of SHRs, we focused on vasomotor responses and end points that are highly relevant for cellular reactive oxygen species (ROS) production, inflammatory cytokine expression and NF-κB activation. KEY RESULTS SHRs treated with HET0016 remained hypertensive (SHR + HET0016: 149 ± 8 mmHg, Wistar-Kyoto rat: 115 ± 4 mmHg; P < 0.05.), although their systolic blood pressure was decreased compared to untreated SHRs (191 ± 6 mmHg). In MCAs of SHRs, flow-induced constriction was increased, whereas ACh- and ATP-induced dilations were impaired. This functional impairment was reversed by treatment with HET0016. Treatment with HET0016 also significantly decreased oxidative stress in MCAs of SHRs (as shown by dihydroethidium staining and analysis of vascular 5-nitrotyrosine, 4-hydroxynonenal and carbonyl content) and inhibited cerebrovascular inflammation (shown by the reduced mRNA expression of TNFα, IL-1β and IL-6). Treatment of SHRs with HET0016 also attenuated vascular NF-κB activation. In vitro treatment with 20-HETE significantly increased vascular production of ROS and promoted NF-κB activation in cultured cerebromicrovascular endothelial cells. CONCLUSIONS AND IMPLICATIONS Taken together, treatment with HET0016 confers anti-oxidative and anti-inflammatory effects in the cerebral arteries of SHRs by disrupting 20-HETE-mediated autocrine/paracrine signalling pathways in the vascular wall. It is likely that HET0016-induced decreases in blood pressure also potentiate the cerebrovascular protective effects of the drug.
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Affiliation(s)
- Peter Toth
- Reynolds Oklahoma Center on Aging, Department of Geriatric Medicine, University of Oklahoma, Oklahoma City, OK 73104, USA
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Pikilidou M, Yavropoulou M, Antoniou M, Yovos J. The Contribution of Osteoprogenitor Cells to Arterial Stiffness and Hypertension. J Vasc Res 2015; 52:32-40. [DOI: 10.1159/000381098] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 02/15/2015] [Indexed: 11/19/2022] Open
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Nitric oxide and reactive oxygen species in the pathogenesis of preeclampsia. Int J Mol Sci 2015; 16:4600-14. [PMID: 25739077 PMCID: PMC4394437 DOI: 10.3390/ijms16034600] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 01/13/2015] [Accepted: 02/15/2015] [Indexed: 01/08/2023] Open
Abstract
Preeclampsia (PE) is characterized by disturbed extravillous trophoblast migration toward uterine spiral arteries leading to increased uteroplacental vascular resistance and by vascular dysfunction resulting in reduced systemic vasodilatory properties. Its pathogenesis is mediated by an altered bioavailability of nitric oxide (NO) and tissue damage caused by increased levels of reactive oxygen species (ROS). Furthermore, superoxide (O2−) rapidly inactivates NO and forms peroxynitrite (ONOO−). It is known that ONOO− accumulates in the placental tissues and injures the placental function in PE. In addition, ROS could stimulate platelet adhesion and aggregation leading to intravascular coagulopathy. ROS-induced coagulopathy causes placental infarction and impairs the uteroplacental blood flow in PE. The disorders could lead to the reduction of oxygen and nutrients required for normal fetal development resulting in fetal growth restriction. On the other hand, several antioxidants scavenge ROS and protect tissues against oxidative damage. Placental antioxidants including catalase, superoxide dismutase (SOD), and glutathione peroxidase (GPx) protect the vasculature from ROS and maintain the vascular function. However, placental ischemia in PE decreases the antioxidant activity resulting in further elevated oxidative stress, which leads to the appearance of the pathological conditions of PE including hypertension and proteinuria. Oxidative stress is defined as an imbalance between ROS and antioxidant activity. This review provides new insights about roles of oxidative stress in the pathophysiology of PE.
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Enhanced vascular PI3K/Akt-NOX signaling underlies the peripheral NMDAR-mediated pressor response in conscious rats. J Cardiovasc Pharmacol 2014; 63:395-405. [PMID: 24336015 DOI: 10.1097/fjc.0000000000000059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The molecular mechanisms for peripheral N-methyl-D-aspartate receptor (NMDAR)-mediated vascular oxidative stress and pressor response are not known. We conducted integrative (in vivo) and ex vivo biochemical studies to test the hypothesis that reactive oxygen species (ROS)-dependent calcium influx, triggered by the activation of vascular kinases, underlies the NMDAR-mediated pressor response. Pharmacological inhibition of phosphoinositide 3-kinase (PI3K)/Akt (wortmannin, 15 μg/kg), protein kinase C (chelerythrine: 5 mg/kg, intravenous), Ca²⁺ influx (nifedipine, 0.35 or 0.75 mg/kg), or NADPH oxidase (NOX: apocynin, 5 mg/kg) attenuated the peripheral NMDAR-mediated pressor response in conscious male Sprague-Dawley rats. NMDAR activation enhanced the phosphorylation of Akt, ERK1, JNK and p38 (Western blot), and NOX activity in vascular tissues collected during the pressor response caused by NMDA infusion (180 μg·kg⁻¹·min⁻¹, 30 minutes). Furthermore, ex vivo studies showed that wortmannin, chelerythrine, or apocynin abrogated the NMDAR-mediated vascular nitric oxide (NO) and ROS generation and NOX activation in the vasculature. These findings implicate vascular PI3K/Akt-protein kinase C signaling in the peripheral NMDAR-mediated increases in vascular NO and NOX activation (ROS), which ultimately lead to calcium influx and pressor response in conscious rats.
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Lewandowski AJ, Davis EF, Yu G, Digby JE, Boardman H, Whitworth P, Singhal A, Lucas A, McCormick K, Shore AC, Leeson P. Elevated blood pressure in preterm-born offspring associates with a distinct antiangiogenic state and microvascular abnormalities in adult life. Hypertension 2014; 65:607-14. [PMID: 25534704 DOI: 10.1161/hypertensionaha.114.04662] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Preterm-born individuals have elevated blood pressure. We tested the hypothesis that this associates with an enhanced antiangiogenic circulating profile and that this association is mediated by variations in capillary density. We studied 204 adults aged 25 years (range, 20-30 years), of which 102 had been followed up prospectively since very preterm birth (mean gestational age, 30.3±2.5 weeks) and 102 were born term to uncomplicated pregnancies. A panel of circulating biomarkers, including soluble endoglin and soluble fms-like tyrosine kinase-1, were compared between groups and related to perinatal history and adult cardiovascular risk. Associations with cardiovascular phenotype were studied in 90 individuals who had undergone detailed assessment of microvascular, macrovascular, and cardiac structure and function. Preterm-born individuals had elevations in soluble endoglin (5.64±1.03 versus 4.06±0.85 ng/mL; P<0.001) and soluble fms-like tyrosine kinase-1 (88.1±19.0 versus 73.0±15.3 pg/mL; P<0.001) compared with term-born individuals, proportional to elevations in resting and ambulatory blood pressure, as well as degree of prematurity (P<0.05). Maternal hypertensive pregnancy disorder was associated with additional increases in soluble fms-like tyrosine kinase-1 (P=0.002). Other circulating biomarkers, including those of inflammation and endothelial activation, were not related to blood pressure. There was a specific graded association between soluble endoglin and degree of functional and structural capillary rarefaction (P=0.002 and P<0.001), and in multivariable analysis, there were capillary density-mediated associations between soluble endoglin and blood pressure. Preterm-born individuals exhibit an enhanced antiangiogenic state in adult life that is specifically related to elevations in blood pressure. The association seems to be mediated through capillary rarefaction and is independent of other cardiovascular structural and functional differences in the offspring.
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Affiliation(s)
- Adam J Lewandowski
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Esther F Davis
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Grace Yu
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Janet E Digby
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Henry Boardman
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Polly Whitworth
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Atul Singhal
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Alan Lucas
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Kenny McCormick
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Angela C Shore
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.)
| | - Paul Leeson
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom (A.J.L., E.F.D., G.Y., J.E.D., H.B., P.W., P.L.); Department of Clinical Epidemiology, Nutrition and Biostatistics, Institute of Child Health, University College London, London, United Kingdom (A.S., A.L.); Department of Paediatrics, John Radcliffe Hospital, Oxford, United Kingdom (K.M.); and Department of Vascular Medicine, NIHR Exeter Clinical Research Facility, University of Exeter Medical School, Exeter, United Kingdom (A.C.S.).
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Staiculescu MC, Foote C, Meininger GA, Martinez-Lemus LA. The role of reactive oxygen species in microvascular remodeling. Int J Mol Sci 2014; 15:23792-835. [PMID: 25535075 PMCID: PMC4284792 DOI: 10.3390/ijms151223792] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/05/2014] [Accepted: 12/10/2014] [Indexed: 02/07/2023] Open
Abstract
The microcirculation is a portion of the vascular circulatory system that consists of resistance arteries, arterioles, capillaries and venules. It is the place where gases and nutrients are exchanged between blood and tissues. In addition the microcirculation is the major contributor to blood flow resistance and consequently to regulation of blood pressure. Therefore, structural remodeling of this section of the vascular tree has profound implications on cardiovascular pathophysiology. This review is focused on the role that reactive oxygen species (ROS) play on changing the structural characteristics of vessels within the microcirculation. Particular attention is given to the resistance arteries and the functional pathways that are affected by ROS in these vessels and subsequently induce vascular remodeling. The primary sources of ROS in the microcirculation are identified and the effects of ROS on other microcirculatory remodeling phenomena such as rarefaction and collateralization are briefly reviewed.
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Affiliation(s)
- Marius C Staiculescu
- Dalton Cardiovascular Research Center, and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211, USA.
| | - Christopher Foote
- Dalton Cardiovascular Research Center, and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211, USA.
| | - Gerald A Meininger
- Dalton Cardiovascular Research Center, and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211, USA.
| | - Luis A Martinez-Lemus
- Dalton Cardiovascular Research Center, and Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65211, USA.
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29
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Endothelial dysfunction in experimental models of arterial hypertension: cause or consequence? BIOMED RESEARCH INTERNATIONAL 2014. [PMID: 24738065 DOI: 10.1155/2014/598271.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hypertension is a risk factor for other cardiovascular diseases and endothelial dysfunction was found in humans as well as in various commonly employed animal experimental models of arterial hypertension. Data from the literature indicate that, in general, endothelial dysfunction would not be the cause of experimental hypertension and may rather be secondary, that is, resulting from high blood pressure (BP). The initial mechanism of endothelial dysfunction itself may be associated with a lack of endothelium-derived relaxing factors (mainly nitric oxide) and/or accentuation of various endothelium-derived constricting factors. The involvement and role of endothelium-derived factors in the development of endothelial dysfunction in individual experimental models of hypertension may vary, depending on the triggering stimulus, strain, age, and vascular bed investigated. This brief review was focused on the participation of endothelial dysfunction, individual endothelium-derived factors, and their mechanisms of action in the development of high BP in the most frequently used rodent experimental models of arterial hypertension, including nitric oxide deficient models, spontaneous (pre)hypertension, stress-induced hypertension, and selected pharmacological and diet-induced models.
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Szijártó IA, Molnár GA, Mikolás E, Fisi V, Laczy B, Gollasch M, Koller A, Wittmann I. Increase in insulin-induced relaxation of consecutive arterial segments toward the periphery: Role of vascular oxidative state. Free Radic Res 2014; 48:749-57. [PMID: 24628420 DOI: 10.3109/10715762.2014.904507] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
RATIONALE The oxidative state has been implicated in the signaling of various vasomotor functions, yet its role regarding the vasomotor action of insulin is less known. OBJECTIVE To investigate the insulin-evoked relaxations of consecutive arterial segments of different oxidative state and the role of extracellular signal-regulated kinase (ERK) pathway. METHODS AND RESULTS The oxidative state, as assessed by the level of ortho-tyrosine, was higher in the thoracic aorta of rats than in the abdominal aorta, and was the lowest in the femoral artery. The vasomotor function of vessels of same origin was studied using a small-vessel myograph. Insulin-induced relaxations increased toward the periphery (i.e., thoracic < abdominal < femoral). Aortic banding and hydrogen peroxide/aminotriazole increased the oxidative state of the thoracic aorta that was accompanied by ERK activation and decreased relaxation to insulin, and vice versa, acutely lowered oxidative state by superoxide dismutase/catalase improved relaxation. In contrast, insulin-induced relaxation of the femoral artery could be enhanced with a higher oxidative state, and reduced with a lower state. CONCLUSIONS Oxidative state of vessels modulates the magnitude of vasomotor responses to insulin, which appears to be mediated via the ERK signaling pathway.
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Affiliation(s)
- I A Szijártó
- 2nd Department of Medicine and Nephrological Center, University of Pécs , Pécs , Hungary
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31
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Endothelial dysfunction in experimental models of arterial hypertension: cause or consequence? BIOMED RESEARCH INTERNATIONAL 2014; 2014:598271. [PMID: 24738065 PMCID: PMC3971506 DOI: 10.1155/2014/598271] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Accepted: 01/31/2014] [Indexed: 02/07/2023]
Abstract
Hypertension is a risk factor for other cardiovascular diseases and endothelial dysfunction was found in humans as well as in various commonly employed animal experimental models of arterial hypertension. Data from the literature indicate that, in general, endothelial dysfunction would not be the cause of experimental hypertension and may rather be secondary, that is, resulting from high blood pressure (BP). The initial mechanism of endothelial dysfunction itself may be associated with a lack of endothelium-derived relaxing factors (mainly nitric oxide) and/or accentuation of various endothelium-derived constricting factors. The involvement and role of endothelium-derived factors in the development of endothelial dysfunction in individual experimental models of hypertension may vary, depending on the triggering stimulus, strain, age, and vascular bed investigated. This brief review was focused on the participation of endothelial dysfunction, individual endothelium-derived factors, and their mechanisms of action in the development of high BP in the most frequently used rodent experimental models of arterial hypertension, including nitric oxide deficient models, spontaneous (pre)hypertension, stress-induced hypertension, and selected pharmacological and diet-induced models.
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32
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Brandes RP, Weissmann N, Schröder K. Nox family NADPH oxidases in mechano-transduction: mechanisms and consequences. Antioxid Redox Signal 2014; 20:887-98. [PMID: 23682993 PMCID: PMC3924808 DOI: 10.1089/ars.2013.5414] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SIGNIFICANCE The majority of cells in a multi-cellular organism are continuously exposed to ever-changing physical forces. Mechano-transduction links these events to appropriate reactions of the cells involving stimulation of signaling cascades, reorganization of the cytoskeleton and alteration of gene expression. RECENT ADVANCES Mechano-transduction alters the cellular redox balance and the formation of reactive oxygen species (ROS). Nicotine amide adenine dinucleotide reduced form (NADPH) oxidases of the Nox family are prominent ROS generators and thus, contribute to this stress-induced ROS formation. CRITICAL ISSUES Different types and patterns of mechano-stress lead to Nox-dependent ROS formation and Nox-mediated ROS formation contributes to cellular responses and adaptation to physical forces. Thereby, Nox enzymes can mediate vascular protection during physiological mechano-stress. Despite this, over-activation and induction of Nox enzymes and a subsequent substantial increase in ROS formation also promotes oxidative stress in pathological situations like disturbed blood flow or extensive stretch. FUTURE DIRECTIONS Individual protein targets of Nox-mediated redox-signaling will be identified to better understand the specificity of Nox-dependent ROS signaling in mechano-transduction. Nox-inhibitors will be tested to reduce cellular activation in response to mechano-stimuli.
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Affiliation(s)
- Ralf P Brandes
- 1 Institut für Kardiovaskuläre Physiologie, Goethe-Universität Frankfurt , Frankfurt am Main, Germany
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Monturiol-Gross L, Flores-Díaz M, Pineda-Padilla MJ, Castro-Castro AC, Alape-Giron A. Clostridium perfringens phospholipase C induced ROS production and cytotoxicity require PKC, MEK1 and NFκB activation. PLoS One 2014; 9:e86475. [PMID: 24466113 PMCID: PMC3900566 DOI: 10.1371/journal.pone.0086475] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 12/11/2013] [Indexed: 02/07/2023] Open
Abstract
Clostridium perfringens phospholipase C (CpPLC), also called α-toxin, is the most toxic extracellular enzyme produced by this bacteria and is essential for virulence in gas gangrene. At lytic concentrations, CpPLC causes membrane disruption, whereas at sublytic concentrations this toxin causes oxidative stress and activates the MEK/ERK pathway, which contributes to its cytotoxic and myotoxic effects. In the present work, the role of PKC, ERK 1/2 and NFκB signalling pathways in ROS generation induced by CpPLC and their contribution to CpPLC-induced cytotoxicity was evaluated. The results demonstrate that CpPLC induces ROS production through PKC, MEK/ERK and NFκB pathways, the latter being activated by the MEK/ERK signalling cascade. Inhibition of either of these signalling pathways prevents CpPLC's cytotoxic effect. In addition, it was demonstrated that NFκB inhibition leads to a significant reduction in the myotoxicity induced by intramuscular injection of CpPLC in mice. Understanding the role of these signalling pathways could lead towards developing rational therapeutic strategies aimed to reduce cell death during a clostridialmyonecrosis.
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Affiliation(s)
- Laura Monturiol-Gross
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Marietta Flores-Díaz
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Maria Jose Pineda-Padilla
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | | | - Alberto Alape-Giron
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
- Departamento de Bioquímica, Escuela de Medicina, Universidad de Costa Rica, San José, Costa Rica
- Centro de investigación en estructuras microscópicas, Universidad de Costa Rica, San José, Costa Rica
- * E-mail:
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Abstract
Based on mosaic theory, hypertension is a multifactorial disorder that develops because of genetic, environmental, anatomical, adaptive neural, endocrine, humoral, and hemodynamic factors. It has been recently proposed that oxidative stress may contribute to all of these factors and production of reactive oxygen species (ROS) play an important role in the development of hypertension. Previous studies focusing on the role of vascular NADPH oxidases provided strong support of this concept. Although mitochondria represent one of the most significant sources of cellular ROS generation, the regulation of mitochondrial ROS generation in the cardiovascular system and its pathophysiological role in hypertension are much less understood. In this review, the role of mitochondrial oxidative stress in the pathophysiology of hypertension and cross talk between angiotensin II signaling, pathways involved in mechanotransduction, NADPH oxidases, and mitochondria-derived ROS are considered. The possible benefits of therapeutic strategies that have the potential to attenuate mitochondrial oxidative stress for the prevention/treatment of hypertension are also discussed.
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Affiliation(s)
- Sergey I Dikalov
- Division of Clinical Pharmacology, Free Radicals in Medicine Core, Vanderbilt University Medical Center, Nashville, Tennessee; and
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35
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Endothelial dysfunction in diabetes and hypertension: cross talk in RAS, BMP4, and ROS-dependent COX-2-derived prostanoids. J Cardiovasc Pharmacol 2013; 61:204-14. [PMID: 23232839 DOI: 10.1097/fjc.0b013e31827fe46e] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Vascular endothelium regulates cardiovascular function, and endothelial dysfunction is the key initiator for arteriosclerosis and thrombosis and their complications. The endothelium is a dynamic interface that responds to various stimuli and synthesizes and liberates vasoactive molecules such as nitric oxide, prostaglandins, hyperpolarizing factor, and endothelin. Risk factors such as hypertension, hypercholesterolemia, smoking, and hyperglycemia impair the ability of the endothelium to respond to physical or chemical stimulation appropriately, and increased oxidative stress is believed to be a major culprit. This brief article reviews the interplay among several oxidative stress regulators in the vascular wall and highlights therapeutic relevance through deeper understanding of the interplay between the renin-angiotensin system, nicotinamide adenine dinucleotide phosphate, reduced oxidase, bone morphogenic protein 4, and cyclooxygenase 2-derived prostaglandins as a concerted pathogenic cascade in inducing and maintaining endothelial dysfunction in hypertension and diabetes.
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de Queiroz TM, Monteiro MMO, Braga VA. Angiotensin-II-derived reactive oxygen species on baroreflex sensitivity during hypertension: new perspectives. Front Physiol 2013; 4:105. [PMID: 23717285 PMCID: PMC3651964 DOI: 10.3389/fphys.2013.00105] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 04/24/2013] [Indexed: 12/12/2022] Open
Abstract
Hypertension is a multifactorial disorder, which has been associated with the reduction in baroreflex sensitivity (BRS) and autonomic dysfunction. Several studies have revealed that increased reactive oxygen species (ROS) generated by nicotinamide adenine dinucleotide phosphate [NAD(P)H] oxidase, following activation of type 1 receptor (AT1R) by Angiotensin-(Ang) II, the main peptide of the Renin–Angiotensin–Aldosterone System (RAAS), is the central mechanism involved in Ang-II-derived hypertension. In the present review, we will discuss the role of Ang II and oxidative stress in hypertension, the relationship between the BRS and the genesis of hypertension and how the oxidative stress triggers baroreflex dysfunction in several models of hypertension. Finally, we will describe some novel therapeutic drugs for improving the BRS during hypertension.
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Affiliation(s)
- Thyago M de Queiroz
- Department of Biotechnology, Biotechnology Center, Federal University of Paraiba João Pessoa, Brazil
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Marín C, Yubero-Serrano EM, López-Miranda J, Pérez-Jiménez F. Endothelial aging associated with oxidative stress can be modulated by a healthy mediterranean diet. Int J Mol Sci 2013; 14:8869-89. [PMID: 23615475 PMCID: PMC3676761 DOI: 10.3390/ijms14058869] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 03/28/2013] [Accepted: 04/02/2013] [Indexed: 12/12/2022] Open
Abstract
Aging is a condition which favors the development of atherosclerosis, which has been associated with a breakdown in repair processes that occurs in response to cell damage. The dysregulation of the biological systems associated with aging are produced partly through damage which accumulates over time. One major source of this injury is oxidative stress, which can impair biological structures and the mechanisms by which they are repaired. These mechanisms are based on the pathogenesis of endothelial dysfunction, which in turn is associated with cardiovascular disease, carcinogenesis and aging. The dependent dysfunction of aging has been correlated with a reduction in the number and/or functional activity of endothelial progenitor cells, which could hinder the repair and regeneration of the endothelium. In addition, aging, inflammation and oxidative stress are endogenous factors that cause telomere shortening, which is dependent on oxidative cell damage. Moreover, telomere length correlates with lifestyle and the consumption of a healthy diet. Thus, diseases associated with aging and age may be caused by the long-term effects of oxidative damage, which are modified by genetic and environmental factors. Considering that diet is a very important source of antioxidants, in this review we will analyze the relationship between oxidative stress, aging, and the mechanisms which may be involved in a higher survival rate and a lower incidence of the diseases associated with aging in populations which follow a healthy diet.
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Affiliation(s)
- Carmen Marín
- Lipids and Atherosclerosis Unit, Maimonides Institute for Research in Biomedicina at Cordoba (IMIBIC)/Reina Sofia University Hospital/University of Cordoba and CIBER Fisiopatologia Obesidad y Nutricion (CIBERobn), Instituto de Salud Carlos III, Cordoba, 14004, Spain.
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Schutte R, Huisman HW, Malan L, van Rooyen JM, Smith W, Glyn MCP, Mels CMC, Fourie CMT, Malan NT, Schutte AE. Alkaline phosphatase and arterial structure and function in hypertensive African men: the SABPA study. Int J Cardiol 2012; 167:1995-2001. [PMID: 22656046 DOI: 10.1016/j.ijcard.2012.05.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 03/23/2012] [Accepted: 05/05/2012] [Indexed: 01/22/2023]
Abstract
BACKGROUND Vascular calcification is believed to be due to the conversion of vascular smooth muscle cells into osteoblast-like cells and is associated with mortality. Since hypertension and related mortality in Africans is a concern, we investigated associations between a marker of osteoblastic activity, alkaline phosphatase (ALP), and measures of arterial structure and function in hypertensive African men. METHODS This study included 79 participants. We conducted 24h ambulatory blood pressure and carotid intima-media thickness (cIMT) measurements. cIMT was obtained with an intra-observer variability of 0.04 mm and the cross-sectional wall area (CSWA) was calculated. ALP was measured in serum. RESULTS ALP was within its reference range (101.6 vs. 30.0-120.0 U/L), however cIMT was higher when this group was stratified and compared to gender and age-specific reference values. In univariate and partial regressions, and confirmed with multiple regression analyses, 24h systolic blood pressure (β=0.289, p=0.018), 24h pulse pressure (β=0.387, p=0.002), but not 24h diastolic blood pressure (β=0.073, p=0.58), were positively associated with ALP. In addition, mean cIMT (β=0.322, p=0.006) and CSWA (β=0.285, p=0.013) also correlated positively with ALP after adjusting for significant covariates, and after excluding participants with diabetes, renal dysfunction or a HIV positive status. CONCLUSION Serum alkaline phosphatase is adversely associated with measures of arterial structure and function in hypertensive African men.
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Affiliation(s)
- R Schutte
- Hypertension in Africa Research Team, School for Physiology, Nutrition, Consumer Sciences, North-West University, Potchefstroom Campus, Potchefstroom, South Africa.
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Ruseva B, Atanasova M, Georgieva M, Shumkov N, Laleva P. Effects of selenium on the vessel walls and anti-elastin antibodies in spontaneously hypertensive rats. Exp Biol Med (Maywood) 2012; 237:160-6. [PMID: 22312058 DOI: 10.1258/ebm.2011.011212] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Selenium (Se) is an exogenous antioxidant that performs its role via expression of selenoproteins. Pathological changes of the structure of the vessel wall, elastin turnover and collagen production may lead to increased stiffness of the vessels with decreased blood flow to the peripheries. The level of anti-elastin antibodies (AEABs) may give information for elastin metabolism. The aim of the study is to investigate the influence of Se intake on the vessel wall changes and production of AEABs in spontaneously hypertensive rats (SHR). Twenty-four male, 32-week-old SHR were used, divided into three groups, G1, G2 and G3. Before blood and morphological testing, G1 received a low-Se diet for eight weeks, G2 received a diet with adequate Se content and G3 received a diet with Se supplementation. The Se nutritional status was assessed by determination of glutathione peroxidase-1 (GPx-1) activity in whole blood, using the 'Ransel' kit. The rats from group G3 showed higher GPx-1 activity and lower level of AEABs than the other groups (P = 0.021), and the aortic wall histology showed slight degenerative changes compared with other rats. A low-Se diet caused severe changes to the aortic wall's ultrastructure, whereas Se supplementation slowed the changes down. The morphometry revealed a thicker abdominal aortic wall in rats of G1 compared with the other groups, and reduced thickness of the wall of the left coronary artery in G3 compared with the other groups (P < 0.05). Our results have shown that low Se intake leads to severe changes in the vessel walls in SHR, whereas selenium supplementation slows down the elastin degradation and degenerative changes of the vessel walls.
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Affiliation(s)
- Boryana Ruseva
- Department of Physiology, Medical University-Pleven, 1 Kliment Ohridski Street, Pleven, Bulgaria.
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Microvascular brain damage with aging and hypertension: pathophysiological consideration and clinical implications. J Hypertens 2012; 29:1469-77. [PMID: 21577138 DOI: 10.1097/hjh.0b013e328347cc17] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Loss of cognitive function and hypertension are two common conditions in the elderly and both significantly contribute to loss of personal independency. Microvascular brain damage - the result of age-associated alteration in large arteries and the progressive mismatch of their cross-talk with small cerebral arteries - represents a potent risk factor for cognitive decline and for the onset of dementia in older individuals. The present review discusses the complexity of factors linking large artery to microvascular brain disease and to cognitive decline and the evidence for possible clinical markers useful for prevention of this phenomenon. The possibility of dementia prevention by cardiovascular risk factors control has not been demonstrated. In the absence of research clinical trials specifically and primarily designed to demonstrate the antihypertensive treatment efficacy for reducing the risk of dementia, further evidence demonstrating that it is possible to limit the progression of microvascular brain damage is needed.
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Lau YS, Machha A, Achike FI, Murugan D, Mustafa MR. The aporphine alkaloid boldine improves endothelial function in spontaneously hypertensive rats. Exp Biol Med (Maywood) 2012; 237:93-8. [DOI: 10.1258/ebm.2011.011145] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Boldine, a major aporphine alkaloid found in Chilean boldo tree, is a potent antioxidant. Oxidative stress plays a detrimental role in the pathogenesis of endothelial dysfunction in hypertension. In the present study, we investigated the effects of boldine on endothelial dysfunction in hypertension using spontaneously hypertensive rats (SHR), the most studied animal model of hypertension. SHR and their age-matched normotensive Wistar-Kyoto (WKY) rats were treated with boldine (20 mg/kg per day) or its vehicle, which served as control, for seven days. Control SHR displayed higher systolic blood pressure (SBP), reduced endothelium-dependent aortic relaxation to acetylcholine (ACh), marginally attenuated endothelium-independent aortic relaxation to sodium nitroprusside (SNP), increased aortic superoxide and peroxynitrite production, and enhanced p47phox protein expression as compared with control WKY rats. Boldine treatment significantly lowered SBP in SHR but not in WKY. Boldine treatment enhanced the maximal relaxation to ACh in SHR, but had no effect in WKY, whereas the sensitivity to ACh was increased in both SHR and WKY aortas. Boldine treatment enhanced sensitivity, but was without effect on maximal aortic relaxation responses, to SNP in both WKY and SHR aortas. In addition, boldine treatment lowered aortic superoxide and peroxynitrite production and downregulated p47phox protein expression in SHR aortas, but had no effect in the WKY control. These results show that boldine treatment exerts endothelial protective effects in hypertension, achieved, at least in part, through the inhibition of NADPH-mediated superoxide production.
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Affiliation(s)
- Yeh-Siang Lau
- Department of Pharmacology, Faculty of Medicine, Centre of Natural Products and Drug Discovery (CENAR), University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Ajay Machha
- Molecular Medicine Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Francis I Achike
- Clinical Sciences Section, International Medical University, Bukit Jalil, Kuala Lumpur 57000, Malaysia
| | - Dharmani Murugan
- Department of Pharmacology, Faculty of Medicine, Centre of Natural Products and Drug Discovery (CENAR), University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Mohd Rais Mustafa
- Department of Pharmacology, Faculty of Medicine, Centre of Natural Products and Drug Discovery (CENAR), University of Malaya, Kuala Lumpur 50603, Malaysia
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Perivascular Fat and the Microcirculation: Relevance to Insulin Resistance, Diabetes, and Cardiovascular Disease. CURRENT CARDIOVASCULAR RISK REPORTS 2011; 6:80-90. [PMID: 22247785 PMCID: PMC3251783 DOI: 10.1007/s12170-011-0214-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Type 2 diabetes and its major risk factor, obesity, are a growing burden for public health. The mechanisms that connect obesity and its related disorders, such as insulin resistance, type 2 diabetes, and hypertension, are still undefined. Microvascular dysfunction may be a pathophysiologic link between insulin resistance and hypertension in obesity. Many studies have shown that adipose tissue-derived substances (adipokines) interact with (micro)vascular function and influence insulin sensitivity. In the past, research focused on adipokines from perivascular adipose tissue (PVAT). In this review, we focus on the interactions between adipokines, predominantly from PVAT, and microvascular function in relation to the development of insulin resistance, diabetes, and cardiovascular disease.
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Bagi Z, Feher A, Cassuto J, Akula K, Labinskyy N, Kaley G, Koller A. Increased availability of angiotensin AT 1 receptors leads to sustained arterial constriction to angiotensin II in diabetes - role for Rho-kinase activation. Br J Pharmacol 2011; 163:1059-68. [PMID: 21385178 DOI: 10.1111/j.1476-5381.2011.01307.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Antagonists of angiotensin AT(1) receptors elicit beneficial vascular effects in diabetes mellitus. We hypothesized that diabetes induces sustained availability of AT(1) receptors, causing enhanced arterial constriction to angiotensin II. EXPERIMENTAL APPROACH To assess functional availability of AT(1) receptors, constrictions to successive applications of angiotensin II were measured in isolated skeletal muscle resistance arteries (∼150 µm) of Zucker diabetic fatty (ZDF) rats and of their controls (+/Fa), exposed acutely to high glucose concentrations (HG, 25 mM, 1 h). AT(1) receptors on cell membrane surface were measured by immunofluorescence. KEY RESULTS Angiotensin II-induced constrictions to first applications were greater in arteries of ZDF rats (maximum: 82 ± 3% original diameter) than in those from +/Fa rats (61 ± 5%). Constrictions to repeated angiotensin II administration were decreased in +/Fa arteries (20 ± 6%), but were maintained in ZDF arteries (67 ± 4%) and in +/Fa arteries vessels exposed to HG (65 ± 6%). In ZDF arteries and in HG-exposed +/Fa arteries, Rho-kinase activities were enhanced. The Rho-kinase inhibitor, Y27632 inhibited sustained constrictions to angiotensin II in ZDF arteries and in +/Fa arteries exposed to HG. Levels of surface AT(1) receptors on cultured vascular smooth muscle cells (VSMCs) were decreased by angiotensin II but were maintained in VSMCs exposed to HG. In VSMCs exposed to HG and treated with Y27632, angiotensin II decreased surface AT(1) receptors. CONCLUSIONS AND IMPLICATIONS In diabetes, elevated glucose concentrations activate Rho-kinase which inhibits internalization or facilitates recycling of AT(1) receptors, leading to increased functional availability of AT(1) receptors and sustained angiotensin II-induced arterial constriction.
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Affiliation(s)
- Zsolt Bagi
- Department of Physiology, New York Medical College, Valhalla, NY, USA.
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Arterial stiffness, pulse pressure, and cardiovascular disease—Is it possible to break the vicious circle? Atherosclerosis 2011; 218:263-71. [DOI: 10.1016/j.atherosclerosis.2011.04.039] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Revised: 04/26/2011] [Accepted: 04/27/2011] [Indexed: 01/02/2023]
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Endothelium-derived vasoactive agents, AT1 receptors and inflammation. Pharmacol Ther 2011; 131:187-203. [DOI: 10.1016/j.pharmthera.2010.11.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 11/03/2010] [Indexed: 12/25/2022]
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Demarco VG, Whaley-Connell AT, Sowers JR, Habibi J, Dellsperger KC. Contribution of oxidative stress to pulmonary arterial hypertension. World J Cardiol 2010; 2:316-24. [PMID: 21160609 PMCID: PMC2999041 DOI: 10.4330/wjc.v2.i10.316] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 08/18/2010] [Accepted: 08/25/2010] [Indexed: 02/06/2023] Open
Abstract
Recent data implicate oxidative stress as a mediator of pulmonary hypertension (PH) and of the associated pathological changes to the pulmonary vasculature and right ventricle (RV). Increases in reactive oxygen species (ROS), altered redox state, and elevated oxidant stress have been demonstrated in the lungs and RV of several animal models of PH, including chronic hypoxia, monocrotaline toxicity, caveolin-1 knock-out mouse, and the transgenic Ren2 rat which overexpresses the mouse renin gene. Generation of ROS in these models is derived mostly from the activities of the nicotinamide adenine dinucleotide phosphate oxidases, xanthine oxidase, and uncoupled endothelial nitric oxide synthase. As disease progresses circulating monocytes and bone marrow-derived monocytic progenitor cells are attracted to and accumulate in the pulmonary vasculature. Once established, these inflammatory cells generate ROS and secrete mitogenic and fibrogenic cytokines that induce cell proliferation and fibrosis in the vascular wall resulting in progressive vascular remodeling. Deficiencies in antioxidant enzymes also contribute to pulmonary hypertensive states. Current therapies were developed to improve endothelial function, reduce pulmonary artery pressure, and slow the progression of vascular remodeling in the pulmonary vasculature by targeting deficiencies in either NO (PDE-type 5 inhibition) or PGI(2) (prostacyclin analogs), or excessive synthesis of ET-1 (ET receptor blockers) with the intent to improve patient clinical status and survival. New therapies may slow disease progression to some extent, but long term management has not been achieved and mortality is still high. Although little is known concerning the effects of current pulmonary arterial hypertension treatments on RV structure and function, interest in this area is increasing. Development of therapeutic strategies that simultaneously target pathology in the pulmonary vasculature and RV may be beneficial in reducing mortality associated with RV failure.
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Affiliation(s)
- Vincent G Demarco
- Vincent G DeMarco, Adam T Whaley-Connell, James R Sowers, Javad Habibi, Kevin C Dellsperger, Department of Internal Medicine, University of Missouri School of Medicine, Columbia, MO 65212, United States
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Matsubara K, Matsubara Y, Hyodo S, Katayama T, Ito M. Role of nitric oxide and reactive oxygen species in the pathogenesis of preeclampsia. J Obstet Gynaecol Res 2010; 36:239-47. [PMID: 20492372 DOI: 10.1111/j.1447-0756.2009.01128.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
AIM Preeclampsia is characterized by a disruption of general vascular dilatation, which is mainly mediated by nitric oxide (NO) and disturbed by reactive oxygen species (ROS). The present study investigated the roles of NO and ROS in the pathogenesis of preeclampsia. METHODS Serum samples were obtained prospectively. Serum levels of NO(2)/NO(3) (NOx) and creatol (CTL), the oxidized metabolite of creatine, and flow-mediated dilatation (FMD) of brachial artery were measured in normal pregnant women and preeclamptic patients. To evaluate the effect of circulating factors that control vascular function NO synthase (NOS) and NAD(P)H oxidase mRNA expression was evaluated in cultured human umbilical vein endothelial cells using reverse transcriptase polymerase chain reaction. RESULTS Serum NOx concentration was decreased and CTL concentration was increased in preeclamptic patients relative to healthy controls during the first trimester of pregnancy. Further, preeclamptic patients exhibited disrupted FMD, which was regulated in part by NO. Immunohistochemistry demonstrated strong expression of nitrotyrosine in the vasculature of preeclamptic placentas. Treatment with sera derived from preeclamptic patients increased endothelial expression of inducible NOS (iNOS) mRNA, and this increase was inhibited by angiotensin II (Ang II) receptor type 2 (AT2) blocker. Endothelial NAD(P)H oxidase subunit gp91(phox) expression was increased by treatment with sera from preeclamptic patients and this increase was attenuated by Ang II receptor type 1 (AT1) blocker. CONCLUSION The present findings suggest that NO and ROS play important roles in the pathogenesis of preeclampsia and that these roles involve Ang II.
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Affiliation(s)
- Keiichi Matsubara
- Department of Obstetrics and Gynecology, Ehime University School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
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Wang W, Pang L, Palade P. Angiotensin II upregulates Ca(V)1.2 protein expression in cultured arteries via endothelial H(2)O(2) production. J Vasc Res 2010; 48:67-78. [PMID: 20639649 DOI: 10.1159/000318776] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2009] [Accepted: 03/15/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND We previously reported that angiotensin II caused an endothelial-dependent increase in L-type voltage-dependent Ca(2+) channel (Ca(V)1.2) in cultured arteries, but the signaling pathways are not clear. METHODS Endothelial damage was generated by brief intra-arterial perfusion with 0.3% CHAPS. Ca(V)1.2 expression, function and H(2)O(2) were measured by Western blot, tension recording and Amplex Red H(2)O(2) assay kit, respectively. RESULTS Angiotensin II dose-dependently upregulated Ca(V)1.2 expression in endothelium-intact arteries. The angiotensin II upregulation of Ca(V)1.2 expression in endothelium-intact arteries was blocked by NAD(P)H oxidase inhibitor diphenyleneiodonium (DPI), apocynin, a more specific NAD(P)H oxidase inhibitor gp91ds-tat and also by catalase. H(2)O(2) similarly upregulated Ca(V)1.2 expression in endothelium-intact and endothelium-damaged arteries, and the latter effect was also blocked by DPI and apocynin. Angiotensin II increased H(2)O(2) production by endothelium-intact but not by endothelium-damaged arteries, and this effect was blocked by apocynin, catalase and gp91ds-tat. The upregulation of Ca(V)1.2 by angiotensin II and H(2)O(2) is accompanied by an increased tension response to KCl and the Ca(2+) channel activator FPL 64176, and this effect was also attenuated by gp91ds-tat. CONCLUSION These results suggest that angiotensin II stimulates endothelial NAD(P)H oxidase-produced H(2)O(2,) which may additionally act through vascular smooth muscle NAD(P)H oxidase, to upregulate vascular Ca(V)1.2 protein.
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Affiliation(s)
- Wenze Wang
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Ark 72205, USA. wwang @ uams.edu
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Ungvari Z, Bagi Z, Feher A, Recchia FA, Sonntag WE, Pearson K, de Cabo R, Csiszar A. Resveratrol confers endothelial protection via activation of the antioxidant transcription factor Nrf2. Am J Physiol Heart Circ Physiol 2010; 299:H18-24. [PMID: 20418481 DOI: 10.1152/ajpheart.00260.2010] [Citation(s) in RCA: 402] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epidemiological studies suggest that Mediterranean diets rich in resveratrol are associated with reduced risk of coronary artery disease. Resveratrol was also shown to confer vasoprotection in animal models of type 2 diabetes and aging. However, the mechanisms by which resveratrol exerts its antioxidative vasculoprotective effects are not completely understood. Using a nuclear factor-E(2)-related factor-2 (Nrf2)/antioxidant response element-driven luciferase reporter gene assay, we found that in cultured coronary arterial endothelial cells, resveratrol, in a dose-dependent manner, significantly increases transcriptional activity of Nrf2. Accordingly, resveratrol significantly upregulates the expression of the Nrf2 target genes NAD(P)H:quinone oxidoreductase 1, gamma-glutamylcysteine synthetase, and heme oxygenase-1. Resveratrol treatment also significantly attenuated high glucose (30 mM)-induced mitochondrial and cellular oxidative stress (assessed by flow cytometry using MitoSox and dihydroethidine staining). The aforementioned effects of resveratrol were significantly attenuated by the small interfering RNA downregulation of Nrf2 or the overexpression of Kelch-like erythroid cell-derived protein 1, which inactivates Nrf2. To test the effects of resveratrol in vivo, we used mice fed a high-fat diet (HFD), which exhibit increased vascular oxidative stress associated with an impaired endothelial function. In HFD-fed Nrf2(+/+) mice, resveratrol treatment attenuates oxidative stress (assessed by the Amplex red assay), improves acetylcholine-induced vasodilation, and inhibits apoptosis (assessed by measuring caspase-3 activity and DNA fragmentation) in branches of the femoral artery. In contrast, the aforementioned endothelial protective effects of resveratrol were diminished in HFD-fed Nrf2(-/-) mice. Taken together, our results indicate that resveratrol both in vitro and in vivo confers endothelial protective effects which are mediated by the activation of Nrf2.
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Affiliation(s)
- Zoltan Ungvari
- Dept. of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th St., Oklahoma City, OK 73104, USA.
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Zhang YF, Wang YXJ, Griffith JF, Kwong WKM, Ma HT, Qin L, Kwok TCY. Proximal femur bone marrow blood perfusion indices are reduced in hypertensive rats: a dynamic contrast-enhanced MRI study. J Magn Reson Imaging 2010; 30:1139-44. [PMID: 19780185 DOI: 10.1002/jmri.21954] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To investigate the differences in proximal femoral bone marrow blood perfusion indices between hypertensive and normotensive rats using perfusion magnetic resonance imaging (MRI). MATERIALS AND METHODS Six-month-old male spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) were used (12 of each). Dynamic contrast-enhanced MRI of the right hip was performed after bolus injection of Gd-DOTA administered through a tail vein cannula. In all, 800 images were acquired at 0.6 sec/image. Regions of interest (ROIs) were drawn comprising the medullary component of proximal femoral shaft and femoral head. MRI maximum enhancement (E(max)) and enhancement slope (E(slope)) were analyzed. RESULTS The E(max) and E(slope) of proximal femoral shaft and femoral head of SHR were significantly lower than those of WKY (E(max): 107.4 +/- 18.2% vs. 130.6 +/- 21.5%, P = 0.009, and 76.0 +/- 12.5% vs. 97.9 +/- 6.9%, P < 0.001, respectively; E(slope): 3.01 +/- 0.63%/sec vs. 3.75 +/- 0.74%/sec, P = 0.016, and 1.95 +/- 0.33%/sec vs. 2.28 +/- 0.28%/sec, P = 0.012, respectively). The E(max) and E(slope) of femoral head were significantly lower than those of proximal femoral shaft in both SHR and WKY (P < 0.001). In both SHR and WKY, proximal femoral shaft and femoral head had a rather different contrast enhancement pattern. CONCLUSION Proximal femoral shaft and femoral head bone marrow blood perfusion indices were significantly lower in hypertensive rats than in normotensive rats. Femoral head bone marrow was less perfused than proximal femoral shaft in both rats.
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Affiliation(s)
- Ya-Feng Zhang
- Department of Medicine and Therapeutics, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
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