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Østergaard AM, Vrist MH, Rosenbæk JB, Ejlersen JA, Mose FH, Bech JN. The effect of orally administered nitrate on renal function and blood pressure in a randomized, placebo-controlled, crossover study in healthy subjects. Nitric Oxide 2023; 134-135:1-9. [PMID: 36906115 DOI: 10.1016/j.niox.2023.03.001] [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: 01/16/2023] [Revised: 03/05/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023]
Abstract
BACKGROUND Several studies have shown inorganic nitrate/nitrite to reduce blood pressure in both healthy subjects and hypertensive patients. An effect presumably caused through bioconversion to nitric oxide. However, studies on inorganic nitrate/nitrite have shown inconsistent results on renal functions such as GFR and sodium excretion. The current study investigated whether orally administered nitrate would decrease blood pressure and increase GFR and urinary sodium excretion. METHODS In a randomized, placebo-controlled, double-blinded, crossover study, 18 healthy subjects received a daily dose of 24 mmol potassium nitrate and placebo (potassium chloride) during 4 days in a randomized order. Subjects also ingested a standardized diet and completed a 24-h urine collection. GFR was determined by the constant infusion technique and during GFR measurement, brachial blood pressure (BP) and central blood pressure (cBP), heart rate, and arterial stiffness were measured every half hour using the Mobil-O-Graph®. Blood samples was analyzed for nitrate, nitrite, cGMP, vasoactive hormones and electrolytes. Urine was analyzed for nitrate, nitrite, cGMP, electrolytes, ENaCγ, NCC, CrCl, CH2O and UO. RESULTS No differences in GFR, blood pressure or sodium excretion were found between the treatments with potassium nitrate and placebo. However, both nitrate and nitrite levels in plasma and urine were significantly increased by potassium nitrate intake and the 24-h urinary excretion of sodium and potassium were stable, showing adherence to the standardized diet and the study medication. CONCLUSION We found no decrease in blood pressure or increase in GFR and sodium excretion of 24 mmol potassium nitrate capsules as compared to placebo after 4 days of treatment. Healthy subjects may be able to compensate the effects of nitrate supplementation during steady state conditions. Future research should focus on long-term studies on the difference in response between healthy subjects and patients with cardiac or renal disease.
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Affiliation(s)
- A M Østergaard
- University Clinic in Nephrology and Hypertension, and Aarhus University, Denmark.
| | - M H Vrist
- University Clinic in Nephrology and Hypertension, and Aarhus University, Denmark
| | - J B Rosenbæk
- University Clinic in Nephrology and Hypertension, and Aarhus University, Denmark
| | - J A Ejlersen
- Department of Nuclear Medicine, Gødstrup Hospital, Denmark; Department of Nuclear Medicine, Viborg Hospital, Denmark
| | - F H Mose
- University Clinic in Nephrology and Hypertension, and Aarhus University, Denmark
| | - J N Bech
- University Clinic in Nephrology and Hypertension, and Aarhus University, Denmark
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2
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Villar M, Godwin I, Hegarty R, Erler D, Farid H, Nolan J. Nitrate and nitrite absorption, recycling and retention in tissues of sheep. Small Rumin Res 2021. [DOI: 10.1016/j.smallrumres.2021.106392] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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3
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Wang H, Zhang X, Wang S, Ma H, Shen Y, Wang X. A Multifunctional Electrochemical Sensor for the Simultaneous Detection of Ascorbic Acid, Dopamine, Uric Acid, and Nitrite. J AOAC Int 2021; 104:860-866. [PMID: 33201187 DOI: 10.1093/jaoacint/qsaa157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 11/01/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Ascorbic acid (AA), dopamine (DA), uric acid (UA), and nitrite (NO2-) are essential biomarkers for human metabolism and can be used to indicate some chronic diseases and metabolic disorders, including scurvy, Parkinson's disease, hyperuricemia, and kidney disease. OBJECTIVE A multifunctional electrochemical sensor that can integrate the detection of these species was constructed using nanoporous gold (NPG) as a recognition element to modify glassy carbon electrode (GCE). METHODS The electrochemical performance of the multifunctional electrochemical sensor was investigated toward AA, DA, UA, and NO2- in citrate buffer solution (CBS, 100 mM, pH 4.0) and human serum using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. RESULTS In the quaternary mixture detection, the resulting NPG/GCE electrode displayed four independent oxidation peaks with wide peak separations. Further, the NPG/GCE electrode showed good linear responses with the sensitivities of 32, 1103, 71, and 147 μA/mM/cm2 and the detection limits of 1.58, 0.17, 0.37, and 0.36 μM for AA, DA UA, and NO2-, respectively. Additionally, the NPG/GCE electrode exhibited great anti-interference and was successfully applied in human serum samples. CONCLUSIONS These results indicate that the NPG/GCE electrode can simultaneously and selectively detect AA, DA, UA, and NO2-, which has the potential for application and diagnosis in the screening and diagnosis of chronic diseases and metabolic disorders. HIGHLIGHTS A multianalyte electrochemical sensor was fabricated for human metabolites detection. The sensor displayed good performance in the simultaneous detection of AA, DA, UA, and NO2- and applied to human serum samples.
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Affiliation(s)
- Huimin Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P.R. China
| | - Xueli Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P.R. China
| | - Shuangjue Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P.R. China
| | - Hanyue Ma
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P.R. China
| | - Yaling Shen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, P.R. China
| | - Xia Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P.R. China
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4
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Paulo M, Costa DEFR, Bonaventura D, Lunardi CN, Bendhack LM. Nitric Oxide Donors as Potential Drugs for the Treatment of Vascular Diseases Due to Endothelium Dysfunction. Curr Pharm Des 2021; 26:3748-3759. [PMID: 32427079 DOI: 10.2174/1381612826666200519114442] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/07/2020] [Indexed: 11/22/2022]
Abstract
Endothelial dysfunction and consequent vasoconstriction are a common condition in patients with hypertension and other cardiovascular diseases. Endothelial cells produce and release vasodilator substances that play a pivotal role in normal vascular tone. The mechanisms underlying endothelial dysfunction are multifactorial. However, enhanced reactive oxygen species (ROS) production and consequent vasoconstriction instead of endothelium-derived relaxant generation and consequent vasodilatation contribute to this dysfunction considerably. The main targets of the drugs that are currently used to treat vascular diseases concerning enzyme activities and protein functions that are impaired by endothelial nitric oxide synthase (eNOS) uncoupling and ROS production. Nitric oxide (NO) bioavailability can decrease due to deficient NO production by eNOS and/or NO release to vascular smooth muscle cells, which impairs endothelial function. Considering the NO cellular mechanisms, tackling the issue of eNOS uncoupling could avoid endothelial dysfunction: provision of the enzyme cofactor tetrahydrobiopterin (BH4) should elicit NO release from NO donors, to activate soluble guanylyl cyclase. This should increase cyclic guanosine-monophosphate (cGMP) generation and inhibit phosphodiesterases (especially PDE5) that selectively degrade cGMP. Consequently, protein kinase-G should be activated, and K+ channels should be phosphorylated and activated, which is crucial for cell membrane hyperpolarization and vasodilation and/or inhibition of ROS production. The present review summarizes the current concepts about the vascular cellular mechanisms that underlie endothelial dysfunction and which could be the target of drugs for the treatment of patients with cardiovascular disease.
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Affiliation(s)
- Michele Paulo
- Department Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirao Preto- University of Sao Paulo Av. Do Cafe SN, Brazil
| | - Daniela E F R Costa
- Department of Pharmacology, Biological Sciences Institute, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Daniella Bonaventura
- Department of Pharmacology, Biological Sciences Institute, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Claure N Lunardi
- Laboratory of Photochemistry and Nanobiotechnology, University of Brasilia, Brasilia, Brazil
| | - Lusiane M Bendhack
- Department Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirao Preto- University of Sao Paulo Av. Do Cafe SN, Brazil
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5
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Abstract
The prevalence of cardiovascular and metabolic disease coupled with kidney dysfunction is increasing worldwide. This triad of disorders is associated with considerable morbidity and mortality as well as a substantial economic burden. Further understanding of the underlying pathophysiological mechanisms is important to develop novel preventive or therapeutic approaches. Among the proposed mechanisms, compromised nitric oxide (NO) bioactivity associated with oxidative stress is considered to be important. NO is a short-lived diatomic signalling molecule that exerts numerous effects on the kidneys, heart and vasculature as well as on peripheral metabolically active organs. The enzymatic L-arginine-dependent NO synthase (NOS) pathway is classically viewed as the main source of endogenous NO formation. However, the function of the NOS system is often compromised in various pathologies including kidney, cardiovascular and metabolic diseases. An alternative pathway, the nitrate-nitrite-NO pathway, enables endogenous or dietary-derived inorganic nitrate and nitrite to be recycled via serial reduction to form bioactive nitrogen species, including NO, independent of the NOS system. Signalling via these nitrogen species is linked with cGMP-dependent and independent mechanisms. Novel approaches to restoring NO homeostasis during NOS deficiency and oxidative stress have potential therapeutic applications in kidney, cardiovascular and metabolic disorders.
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6
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Beet on Alps: Time-course changes of plasma nitrate and nitrite concentrations during acclimatization to high-altitude. Nitric Oxide 2020; 107:66-72. [PMID: 33346127 DOI: 10.1016/j.niox.2020.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 12/03/2020] [Accepted: 12/14/2020] [Indexed: 11/21/2022]
Abstract
Nitric oxide seems to be involved in the altitude acclimatization process due to its ability to regulate pulmonary, cardiovascular and muscular responses to hypoxia. In this study, we investigated the plasma nitrate (NO3-) and nitrite (NO2-) response to hypobaric hypoxia in two groups of lowlanders exposed at different altitudes. For seven days, fourteen subjects were evaluated at Casati Hut (3269 m a.s.l. M.CEVEDALE) and eleven individuals were studied at Capanna Regina Margherita (4554 m a.s.l. M.ROSA). Before expeditions and at different time points during high-altitude sojourn, plasma NO3- and NO2- concentrations were measured by chemiluminescence. Resting peripheral arterial oxygen saturation (SpO2), heart rate (HR) and mean arterial blood pressure (MAP) were monitored during the experimental period. Possible confounding factors such as dietary NO3- intake, physical activity and altitude changes were controlled. Sea level plasma NO3- and NO2- concentrations significantly increased at altitude in both M.CEVEDALE group (+26.2 μM, p ≤ 0.0001, 95% CI [+17.6, +34.8] and +559.2 nM, p ≤ 0.0001, [+332.8, +785.6]) and M.ROSA group (+18.7 μM, p ≤ 0.0001, [+10.8, +26.5] and +463.7 nM, p ≤ 0.0001, [+314.3, +613.0]). Average peak value in NO metabolites concentration occurred earlier in M.CEVEDALE group vs M.ROSA group (NO3-, day 3 vs day 5, p = 0.007; NO2-, day 3 vs day 5, p = 0.019). In both groups, resting SpO2, HR and MAP values changed according to altitude levels. This study shows that exposure to hypobaric hypoxia affects nitric oxide metabolites, resulting in a significant increase in plasma NO3- and NO2- concentrations from sea level values. Interestingly, the higher the altitude reached, the longer the time taken to reach a peak in plasma concentrations of nitric oxide metabolites.
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7
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Adewale OO, Bakare MI, Adetunji JB. Mechanism underlying nephroprotective property of curcumin against sodium nitrite-induced nephrotoxicity in male Wistar rat. J Food Biochem 2020; 45:e13341. [PMID: 32648259 DOI: 10.1111/jfbc.13341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/10/2020] [Accepted: 05/15/2020] [Indexed: 12/27/2022]
Abstract
The current work examined the outcome of curcumin (20 mg/kg body weight/day) administration on arginase and adenosine deaminase (ADA) activities and other kidney markers, as well as markers of oxidative stress, in Wistar rats exposed to sodium nitrite (NaNO2 ) (60 mg/kg of body weight, single dose) for 28 days. The results revealed that the NaNO2 exposed rats had significantly altered the ADA activities, arginase activities alongside other biomarkers of kidney function, and oxidative stress. However, pretreatment with curcumin significantly mitigated the altered activities ADA and arginase as well as other parameters. This was supported by the histopathological examination of the kidney tissues. Our findings suggest that the alteration in the activities of ADA and arginase could be involved in the mechanism of action employed by NaNO2 and curcumin in the respective induction and prevention of nephrotoxicity. PRACTICAL APPLICATIONS: These results suggest that moderate exposure to the acceptable daily dose of curcumin can improve food-related kidney damage through regulations of ADA and arginase activities, enhancement in the antioxidant system, and suppression of lipid peroxidation.
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Affiliation(s)
- Omowumi Oyeronke Adewale
- Department of Biochemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria
| | - Matthew Idowu Bakare
- Department of Biochemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria
| | - Juliana Bunmi Adetunji
- Department of Biochemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria
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8
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Cheng HM, Chuang SY, Wang TD, Kario K, Buranakitjaroen P, Chia YC, Divinagracia R, Hoshide S, Minh HV, Nailes J, Park S, Shin J, Siddique S, Sison J, Soenarta AA, Sogunuru GP, Sukonthasarn A, Tay JC, Teo BW, Turana Y, Verma N, Zhang Y, Wang JG, Chen CH. Central blood pressure for the management of hypertension: Is it a practical clinical tool in current practice? J Clin Hypertens (Greenwich) 2019; 22:391-406. [PMID: 31841279 DOI: 10.1111/jch.13758] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 11/12/2019] [Accepted: 11/17/2019] [Indexed: 12/31/2022]
Abstract
Since noninvasive central blood pressure (BP) measuring devices are readily available, central BP has gained growing attention regarding its clinical application in the management of hypertension. The disagreement between central and peripheral BP has long been recognized. Some previous studies showed that noninvasive central BP may be better than the conventional brachial BP in association with target organ damages and long-term cardiovascular outcomes. Recent studies further suggest that the central BP strategy for confirming a diagnosis of hypertension may be more cost-effective than the conventional strategy, and guidance of hypertension management with central BP may result in less use of medications to achieve BP control. Despite the use of central BP being promising, more randomized controlled studies comparing central BP-guided therapeutic strategies with conventional care for cardiovascular events reduction are required because noninvasive central and brachial BP measures are conveniently available. In this brief review, the rationale supporting the utility of central BP in clinical practice and relating challenges are summarized.
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Affiliation(s)
- Hao-Min Cheng
- Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Center for Evidence-Based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Public Health, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Shao-Yuan Chuang
- Institute of Population Health Science, National Health Research Institutes, Miaoli, Taiwan
| | - Tzung-Dau Wang
- Department of Internal Medicine, National Taiwan University College of Medicine, Taipei City, Taiwan
| | - Kazuomi Kario
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Peera Buranakitjaroen
- Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Yook-Chin Chia
- Department of Medical Sciences, School of Healthcare and Medical Sciences, Sunway University, Bandar Sunway, Malaysia.,Department of Primary Care Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Romeo Divinagracia
- University of the East Ramon Magsaysay Memorial Medical Center Inc, Quezon City, Philippines
| | - Satoshi Hoshide
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Huynh Van Minh
- Department of Internal Medicine, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
| | - Jennifer Nailes
- University of the East Ramon Magsaysay Memorial Medical Center Inc, Quezon City, Philippines
| | - Sungha Park
- Division of Cardiology, Cardiovascular Hospital, Yonsei Health System, Seoul, Korea
| | - Jinho Shin
- Faculty of Cardiology Service, Hanyang University Medical Center, Seoul, Korea
| | | | - Jorge Sison
- Section of Cardiology, Department of Medicine, Medical Center Manila, Manila, Philippines
| | - Arieska Ann Soenarta
- Department of Cardiology and Vascular Medicine, Faculty of Medicine, University of Indonesia-National Cardiovascular Center, Jakarta, Indonesia
| | - Guru Prasad Sogunuru
- MIOT International Hospital, Chennai, India.,College of Medical Sciences, Kathmandu University, Bharatpur, Nepal
| | - Apichard Sukonthasarn
- Cardiology Division, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Jam Chin Tay
- Department of General Medicine, Tan Tock Seng Hospital, Singapore, Singapore
| | - Boon Wee Teo
- Division of Nephrology, Department of Medicine, Yong Loo Lin School of Medicine, Singapore, Singapore
| | - Yuda Turana
- Faculty of Medicine and Health Sciences, Atma Jaya Catholic University of Indonesia, Jakarta, Indonesia
| | - Narsingh Verma
- Indian Society of Hypertension, King George's Medical University, Lucknow, India
| | - Yuqing Zhang
- Divisions of Hypertension and Heart Failure, Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ji-Guang Wang
- Department of Hypertension, Centre for Epidemiological Studies and Clinical Trials, the Shanghai Institute of Hypertension, Shanghai Key Laboratory of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Chen-Huan Chen
- Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Center for Evidence-Based Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
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9
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Abstract
Nitrite, an anion produced from the oxidative breakdown of nitric oxide (NO), has traditionally been viewed as an inert molecule. However, this dogma has been challenged with the findings that nitrite can be readily reduced to NO under pathological conditions, hence representing a physiologically relevant storage reservoir of NO either in the blood or tissues. Nitrite administration has been demonstrated to improve myocardial function in subjects with heart failure and to lower the blood pressure in hypertensive subjects. Thus, extensive amount of work has since been carried out to investigate the therapeutic potential of nitrite in treating cardiovascular diseases, especially hypertension. Studies done on several animal models of hypertension have demonstrated the efficacy of nitrite in preventing and ameliorating the pathological changes associated with the disease. This brief review of the current findings aims to re-evaluate the use of nitrite for the treatment of hypertension and in particular to highlight its role in improving endothelial function.
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Affiliation(s)
- Wei Chih Ling
- Department of Pre-clinical Sciences, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Kajang, Selangor; and
| | - Mohd Rais Mustafa
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Dharmani Devi Murugan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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10
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Cumpstey AF, Hennis PJ, Gilbert-Kawai ET, Fernandez BO, Grant D, Jenner W, Poudevigne M, Moyses H, Levett DZ, Cobb A, Meale P, Mitchell K, Pöhnl H, Mythen MG, Grocott MP, Martin DS, Feelisch M. Effects of dietary nitrate supplementation on microvascular physiology at 4559 m altitude - A randomised controlled trial (Xtreme Alps). Nitric Oxide 2019; 94:27-35. [PMID: 31604146 PMCID: PMC6970220 DOI: 10.1016/j.niox.2019.10.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 08/28/2019] [Accepted: 10/07/2019] [Indexed: 12/17/2022]
Abstract
Native highlanders (e.g. Sherpa) demonstrate remarkable hypoxic tolerance, possibly secondary to higher levels of circulating nitric oxide (NO) and increased microcirculatory blood flow. As part of the Xtreme Alps study (a randomised placebo-controlled trial of dietary nitrate supplementation under field conditions of hypobaric hypoxia), we investigated whether dietary supplementation with nitrate could improve NO availability and microvascular blood flow in lowlanders. Plasma measurements of nitrate, nitrite and nitroso species were performed together with measurements of sublingual (sidestream dark-field camera) and forearm blood flow (venous occlusion plethysmography) in 28 healthy adult volunteers resident at 4559 m for 1 week; half receiving a beetroot-based high-nitrate supplement and half receiving an identically-tasting low nitrate ‘placebo’. Dietary supplementation increased plasma nitrate concentrations 4-fold compared to the placebo group, both at sea level (SL; 19.2 vs 76.9 μM) and at day 5 (D5) of high altitude (22.9 vs 84.3 μM, p < 0.001). Dietary nitrate supplementation also significantly increased both plasma nitrite (0.78 vs. 0.86 μM SL, 0.31 vs. 0.41 μM D5, p = 0.03) and total nitroso product (11.3 vs. 19.7 nM SL, 9.7 vs. 12.3 nM D5, p < 0.001) levels both at sea level and at 4559 m. However, plasma nitrite concentrations were more than 50% lower at 4559 m compared to sea level in both treatment groups. Despite these significant changes, dietary nitrate supplementation had no effect on any measured read-outs of sublingual or forearm blood flow, even when environmental hypoxia was experimentally reversed using supplemental oxygen. In conclusion, dietary nitrate supplementation does not improve microcirculatory function at 4559 m. Xtreme Alps is a randomised controlled field study of dietary nitrate at altitude. Dietary nitrate significantly increased plasma nitrate, nitrite & nitroso species. No changes in sublingual blood flow were seen in response to high dietary nitrate. Dietary nitrate did not alter forearm blood flow under any experimental condition. Dietary nitrate supplementation did not improve microcirculatory function at 4559 m
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Affiliation(s)
- Andrew F Cumpstey
- Critical Care Research Area, Southampton, NIHR Southampton Biomedical Research Centre, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK; Anaesthesia and Critical Care Research Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK; Integrative Physiology and Critical Illness Group, Clinical and Experimental Sciences, University of Southampton, Tremona Road, Southampton, SO16 6YD, UK
| | - Philip J Hennis
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - Edward T Gilbert-Kawai
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - Bernadette O Fernandez
- Clinical & Experimental Sciences, Faculty of Medicine, NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK; Warwick Medical School, Division of Metabolic and Vascular Health, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Daniel Grant
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - William Jenner
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - Matthieu Poudevigne
- Clinical & Experimental Sciences, Faculty of Medicine, NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK
| | - Helen Moyses
- Clinical & Experimental Sciences, Faculty of Medicine, NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK
| | - Denny Zh Levett
- Critical Care Research Area, Southampton, NIHR Southampton Biomedical Research Centre, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK; Anaesthesia and Critical Care Research Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK; Integrative Physiology and Critical Illness Group, Clinical and Experimental Sciences, University of Southampton, Tremona Road, Southampton, SO16 6YD, UK
| | - Alexandra Cobb
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - Paula Meale
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - Kay Mitchell
- Critical Care Research Area, Southampton, NIHR Southampton Biomedical Research Centre, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK; Anaesthesia and Critical Care Research Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK; Integrative Physiology and Critical Illness Group, Clinical and Experimental Sciences, University of Southampton, Tremona Road, Southampton, SO16 6YD, UK
| | - Helmut Pöhnl
- AURAPA, Paul-Heidelbauer-Straße 26, 74321, Bietigheim-Bissingen, Germany
| | - Monty G Mythen
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK
| | - Michael Pw Grocott
- Critical Care Research Area, Southampton, NIHR Southampton Biomedical Research Centre, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK; Anaesthesia and Critical Care Research Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK; Integrative Physiology and Critical Illness Group, Clinical and Experimental Sciences, University of Southampton, Tremona Road, Southampton, SO16 6YD, UK
| | - Daniel S Martin
- UCL Centre for Altitude, Space and Extreme Environment (CASE) Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise & Health, 170 Tottenham Court Road, London, W1T 7HA, UK.
| | - Martin Feelisch
- Critical Care Research Area, Southampton, NIHR Southampton Biomedical Research Centre, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK; Integrative Physiology and Critical Illness Group, Clinical and Experimental Sciences, University of Southampton, Tremona Road, Southampton, SO16 6YD, UK; Clinical & Experimental Sciences, Faculty of Medicine, NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK; Warwick Medical School, Division of Metabolic and Vascular Health, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
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11
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Neto-Neves EM, Pinheiro LC, Nogueira RC, Portella RL, Batista RI, Tanus-Santos JE. Sodium nitrite improves hypertension-induced myocardial dysfunction by mechanisms involving cardiac S-nitrosylation. J Mol Cell Cardiol 2019; 134:40-50. [DOI: 10.1016/j.yjmcc.2019.06.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 12/15/2022]
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12
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Carlstrom M, Montenegro MF. Therapeutic value of stimulating the nitrate-nitrite-nitric oxide pathway to attenuate oxidative stress and restore nitric oxide bioavailability in cardiorenal disease. J Intern Med 2019; 285:2-18. [PMID: 30039620 DOI: 10.1111/joim.12818] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cardiovascular disorders including hypertension and associated renal disease are major health problems affecting more than 1.5 billion people worldwide. Apart from nonmodifiable factors such as ageing, family history and gender, both sedentary lifestyle and unhealthy dietary habits are considered as major risk factors. The disorders are interrelated suggesting common pathological pathways. Mechanistically, oxidative stress and compromised function of the nitric oxide synthase (NOS) system leading to endothelial dysfunction and reduction in nitric oxide (NO) bioavailability have been widely implicated and associated with development and progression of disease. New strategies that correct this redox imbalance and increase NO bioactivity may have major clinical implications. The inorganic anions, nitrate and nitrite, are endogenously formed by oxidization of NOS-derived NO, but there are also high amounts of nitrate in our daily diet. In this regard, accumulated evidence over the past two decades demonstrates that these anions can be recycled back to NO and other bioactive nitrogen oxides, thus offering an attractive alternative strategy for therapeutic exploitation. In this review, we describe how dietary stimulation of the nitrate-nitrite-NO pathway affects cardiovascular and renal functions in health and disease via modulation of oxidative stress and NO bioavailability. Clinical studies addressing potential effects on the renal system are still limited, but blood pressure-lowering effects of nitrate supplementation have been demonstrated in healthy and hypertensive subjects as well as in patients with chronic kidney disease. However, larger clinical studies are warranted to reveal whether chronic nitrate treatment can slow-down the progression of cardiorenal disease and associated complications.
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Affiliation(s)
- M Carlstrom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - M F Montenegro
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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Kumar S, Gupta E, Srivastava VK, Kaushik S, Saxena J, Goyal LK, Mehta S, Jyoti A. Nitrosative stress and cytokines are linked with the severity of sepsis and organ dysfunction. Br J Biomed Sci 2018; 76:29-34. [DOI: 10.1080/09674845.2018.1543160] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- S Kumar
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - E Gupta
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - VK Srivastava
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - S Kaushik
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - J Saxena
- Department of Biotechnology, Dr. B. Lal Institute of Biotechnology, Jaipur, India
| | - LK Goyal
- Department of Geriatric Medicine, SMS Medical College & Attached Hospitals, Jaipur, India
| | - S Mehta
- Department of General Medicine, SMS Medical College & Attached Hospitals, Jaipur, India
| | - A Jyoti
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
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14
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Rosenbaek JB, Pedersen EB, Bech JN. The effect of sodium nitrite infusion on renal function, brachial and central blood pressure during enzyme inhibition by allopurinol, enalapril or acetazolamide in healthy subjects: a randomized, double-blinded, placebo-controlled, crossover study. BMC Nephrol 2018; 19:244. [PMID: 30241504 PMCID: PMC6150994 DOI: 10.1186/s12882-018-1035-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 09/03/2018] [Indexed: 12/25/2022] Open
Abstract
Background Sodium nitrite (NaNO2) causes vasodilation, presumably by enzymatic conversion to nitric oxide (NO). Several enzymes with nitrite reducing capabilities have been discovered in vitro, but their relative importance in vivo has not been investigated. We aimed to examine the effects of NaNO2 on blood pressure, fractional sodium excretion (FENa), free water clearance (CH2O) and GFR, after pre-inhibition of xanthine oxidase, carbonic anhydrase, and angiotensin-converting enzyme. The latter as an approach to upregulate endothelial NO synthase activity. Methods In a double-blinded, placebo-controlled, crossover study, 16 healthy subjects were treated, in a randomized order, with placebo, allopurinol 150 mg twice daily (TD), enalapril 5 mg TD, or acetazolamide 250 mg TD. After 4 days of treatment and standardized diet, the subjects were examined at our lab. During intravenous infusion of 240 μg NaNO2/kg/hour for 2 h, we measured changes in brachial and central blood pressure (BP), plasma cyclic guanosine monophosphate (P-cGMP), plasma and urine osmolality, GFR by 51Cr-EDTA clearance, FENa and urinary excretion rate of cGMP (U-cGMP) and nitrite and nitrate (U-NOx). Subjects were supine and orally water-loaded throughout the examination day. Results Irrespective of pretreatment, we observed an increase in FENa, heart rate, U-NOx, and a decrease in CH2O and brachial systolic BP during NaNO2 infusion. P-cGMP and U-cGMP did not change during infusion. We observed a consistent trend towards a reduction in central systolic BP, which was only significant after allopurinol. Conclusion This study showed a robust BP lowering, natriuretic and anti-aquaretic effect of intravenous NaNO2 regardless of preceding enzyme inhibition. None of the three enzyme inhibitors used convincingly modified the pharmacological effects of NaNO2. The steady cGMP indicates little or no conversion of nitrite to NO. Thus the effect of NaNO2 may not be mediated by NO generation. Trial registration EU Clinical Trials Register, 2013-003404-39. Registered December 3 2013.
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Affiliation(s)
- Jeppe B Rosenbaek
- University Clinic in Nephrology and Hypertension, Regional Hospital West Jutland and Aarhus University, Laegaardvej 12J, DK-7500, Holstebro, Denmark.
| | - Erling B Pedersen
- University Clinic in Nephrology and Hypertension, Regional Hospital West Jutland and Aarhus University, Laegaardvej 12J, DK-7500, Holstebro, Denmark
| | - Jesper N Bech
- University Clinic in Nephrology and Hypertension, Regional Hospital West Jutland and Aarhus University, Laegaardvej 12J, DK-7500, Holstebro, Denmark
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15
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Carlström M, Lundberg JO, Weitzberg E. Mechanisms underlying blood pressure reduction by dietary inorganic nitrate. Acta Physiol (Oxf) 2018; 224:e13080. [PMID: 29694703 DOI: 10.1111/apha.13080] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/28/2018] [Accepted: 04/18/2018] [Indexed: 12/20/2022]
Abstract
Nitric oxide (NO) importantly contributes to cardiovascular homeostasis by regulating blood flow and maintaining endothelial integrity. Conversely, reduced NO bioavailability is a central feature during natural ageing and in many cardiovascular disorders, including hypertension. The inorganic anions nitrate and nitrite are endogenously formed after oxidation of NO synthase (NOS)-derived NO and are also present in our daily diet. Knowledge accumulated over the past two decades has demonstrated that these anions can be recycled back to NO and other bioactive nitrogen oxides via serial reductions that involve oral commensal bacteria and various enzymatic systems. Intake of inorganic nitrate, which is predominantly found in green leafy vegetables and beets, has a variety of favourable cardiovascular effects. As hypertension is a major risk factor of morbidity and mortality worldwide, much attention has been paid to the blood pressure reducing effect of inorganic nitrate. Here, we describe how dietary nitrate, via stimulation of the nitrate-nitrite-NO pathway, affects various organ systems and discuss underlying mechanisms that may contribute to the observed blood pressure-lowering effect.
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Affiliation(s)
- M. Carlström
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - J. O. Lundberg
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - E. Weitzberg
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
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16
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Effects of sodium nitrite on renal function and blood pressure in hypertensive vs. healthy study participants. J Hypertens 2018; 36:666-679. [DOI: 10.1097/hjh.0000000000001598] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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17
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Buerk DG, Liu Y, Zaccheo KA, Barbee KA, Jaron D. Nitrite-Mediated Hypoxic Vasodilation Predicted from Mathematical Modeling and Quantified from in Vivo Studies in Rat Mesentery. Front Physiol 2017; 8:1053. [PMID: 29321744 PMCID: PMC5733546 DOI: 10.3389/fphys.2017.01053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/01/2017] [Indexed: 12/26/2022] Open
Abstract
Nitric oxide (NO) generated from nitrite through nitrite reductase activity in red blood cells has been proposed to play a major role in hypoxic vasodilation. However, we have previously predicted from mathematical modeling that much more NO can be derived from tissue nitrite reductase activity than from red blood cell nitrite reductase activity. Evidence in the literature suggests that tissue nitrite reductase activity is associated with xanthine oxidoreductase (XOR) and/or aldehyde oxidoreductase (AOR). We investigated the role of XOR and AOR in nitrite-mediated vasodilation from computer simulations and from in vivo exteriorized rat mesentery experiments. Vasodilation responses to nitrite in the superfusion medium bathing the mesentery equilibrated with 5% O2 (normoxia) or zero O2 (hypoxia) at either normal or acidic pH were quantified. Experiments were also conducted following intraperitoneal (IP) injection of nitrite before and after inhibiting XOR with allopurinol or inhibiting AOR with raloxifene. Computer simulations for NO and O2 transport using reaction parameters reported in the literature were also conducted to predict nitrite-dependent NO production from XOR and AOR activity as a function of nitrite concentration, PO2 and pH. Experimentally, the largest arteriolar responses were found with nitrite >10 mM in the superfusate, but no statistically significant differences were found with hypoxic and acidic conditions in the superfusate. Nitrite-mediated vasodilation with IP nitrite injections was reduced or abolished after inhibiting XOR with allopurinol (p < 0.001). Responses to IP nitrite before and after inhibiting AOR with raloxifene were not as consistent. Our mathematical model predicts that under certain conditions, XOR and AOR nitrite reductase activity in tissue can significantly elevate smooth muscle cell NO and can serve as a compensatory pathway when endothelial NO production is limited by hypoxic conditions. Our theoretical and experimental results provide further evidence for a role of tissue nitrite reductases to contribute additional NO to compensate for reduced NO production by endothelial nitric oxide synthase during hypoxia. Our mathematical model demonstrates that under extreme hypoxic conditions with acidic pH, endogenous nitrite levels alone can be sufficient for a functionally significant increase in NO bioavailability. However, these conditions are difficult to achieve experimentally.
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Affiliation(s)
- Donald G Buerk
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Yien Liu
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Kelly A Zaccheo
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Kenneth A Barbee
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Dov Jaron
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
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18
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Effects of Nitric Oxide on Renal Proximal Tubular Na + Transport. BIOMED RESEARCH INTERNATIONAL 2017; 2017:6871081. [PMID: 29181400 PMCID: PMC5664255 DOI: 10.1155/2017/6871081] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 09/14/2017] [Indexed: 12/28/2022]
Abstract
Nitric oxide (NO) has a wide variety of physiological functions in the kidney. Besides the regulatory effects in intrarenal haemodynamics and glomerular microcirculation, in vivo studies reported the diuretic and natriuretic effects of NO. However, opposite results showing the stimulatory effect of NO on Na+ reabsorption in the proximal tubule led to an intense debate on its physiological roles. Animal studies have showed the biphasic effect of angiotensin II (Ang II) and the overall inhibitory effect of NO on the activity of proximal tubular Na+ transporters, the apical Na+/H+ exchanger isoform 3, basolateral Na+/K+ ATPase, and the Na+/HCO3− cotransporter. However, whether these effects could be reproduced in humans remained unclear. Notably, our recent functional analysis of isolated proximal tubules demonstrated that Ang II dose-dependently stimulated human proximal tubular Na+ transport through the NO/guanosine 3′,5′-cyclic monophosphate (cGMP) pathway, confirming the human-specific regulation of proximal tubular transport via NO and Ang II. Of particular importance for this newly identified pathway is its possibility of being a human-specific therapeutic target for hypertension. In this review, we focus on NO-mediated regulation of proximal tubular Na+ transport, with emphasis on the interaction with individual Na+ transporters and the crosstalk with Ang II signalling.
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Bock JM, Ueda K, Schneider AC, Hughes WE, Limberg JK, Bryan NS, Casey DP. Inorganic nitrate supplementation attenuates peripheral chemoreflex sensitivity but does not improve cardiovagal baroreflex sensitivity in older adults. Am J Physiol Heart Circ Physiol 2017; 314:H45-H51. [PMID: 28971842 DOI: 10.1152/ajpheart.00389.2017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Aging is associated with increased peripheral chemoreceptor activity, reduced nitric oxide (NO) bioavailability, and attenuation of cardiovagal baroreflex sensitivity (BRS), collectively increasing the risk of cardiovascular disease. Evidence suggests that NO may attenuate peripheral chemoreflex sensitivity and increase BRS. Exogenous inorganic nitrate ([Formula: see text]) increases NO bioavailability via the [Formula: see text]-[Formula: see text]-NO pathway. Our hypothesis was that inorganic [Formula: see text] supplementation would attenuate peripheral chemoreflex sensitivity and enhance spontaneous cardiovagal BRS in older adults. We used a randomized, placebo-controlled crossover design in which 13 older (67 ± 3 yr old) adults ingested beetroot powder containing (BRA) or devoid of (BRP) [Formula: see text] and [Formula: see text] daily over 4 wk. Spontaneous cardiovagal BRS was assessed over 15 min of rest and was quantified using the sequence method. Chemoreflex sensitivity was assessed via ~5 min of hypoxia (10% fraction of inspired O2) and reported as the slope of the relationship between O2 saturation (%[Formula: see text]) and minute ventilation (in l/min) or heart rate (in beats/min). Ventilatory responsiveness to hypoxia was reduced after BRA (from -0.14 ± 0.04 to -0.05 ± 0.02 l·min-1·%[Formula: see text]-1, P = 0.01) versus BRP (from -0.10 ± 0.05 to -0.11 ± 0.05 l·min-1·%[Formula: see text]-1, P = 0.80), with no differences in heart rate responsiveness (BRA: from -0.47 ± 0.06 to -0.33 ± 0.04 beats·min-1·%[Formula: see text]-1, BRP: from -0.48 ± 0.07 to -0.42 ± 0.06 beats·min-1·%[Formula: see text]-1) between conditions (interaction effect, P = 0.41). Spontaneous cardiovagal BRS was unchanged after BRA and BRP (interaction effects, P = 0.69, 0.94, and 0.39 for all, up, and down sequences, respectively), despite a reduction in resting systolic and mean arterial blood pressure in the experimental (BRA) group ( P < 0.01 for both). These findings illustrate that inorganic [Formula: see text] supplementation attenuates peripheral chemoreflex sensitivity without concomitant change in spontaneous cardiovagal BRS in older adults. NEW & NOTEWORTHY Exogenous inorganic nitrate supplementation attenuates ventilatory, but not heart rate, responsiveness to abbreviated hypoxic exposure in older adults. Additionally, inorganic nitrate reduces systolic and mean arterial blood pressure without affecting spontaneous cardiovagal baroreflex sensitivity. These findings suggest that inorganic nitrate may attenuate sympathetically oriented pathologies associated with aging.
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Affiliation(s)
- Joshua M Bock
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Kenichi Ueda
- Department of Anesthesia, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Aaron C Schneider
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - William E Hughes
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | | | - Nathan S Bryan
- Department of Molecular and Human Genetics, Baylor College of Medicine , Houston, Texas
| | - Darren P Casey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa.,Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa , Iowa City, Iowa.,Fraternal Order of Eagles Diabetes Research Center, Carver College of Medicine, University of Iowa , Iowa City, Iowa
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