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Gong Y, Tong D, Qiu P, Song R, Li Z, He Y, Luo Q, Tang Q, Zhang K, Liao X. A novel electrochemical biosensor for B-type natriuretic peptide detection based on CRISPR/Cas13a and chain substitution reaction. Talanta 2024; 274:125966. [PMID: 38554484 DOI: 10.1016/j.talanta.2024.125966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 03/18/2024] [Accepted: 03/20/2024] [Indexed: 04/01/2024]
Abstract
B-type natriuretic peptide (BNP) is a biomarker for heart failure, a serious and prevalent disease that requires rapid and accurate diagnosis. In this study, we developed a novel electrochemical biosensor for BNP detection based on CRISPR/Cas13a and chain substitution reaction. The biosensor consists of a DNA aptamer that specifically binds to BNP, a T7 RNA polymerase that amplifies the signal, a CRISPR/Cas13a system that cleaves the target RNA, and a two-dimensional DNA nanoprobe that generates an electrochemical signal. The biosensor exhibits high sensitivity, specificity, and stability, with a detection limit of 0.74 aM. The biosensor can also detect BNP in human serum samples with negligible interference, demonstrating its potential for clinical and point-of-care applications. This study presents a novel strategy for integrating CRISPR/Cas13a and chain substitution reaction into biosensor design, offering a versatile and effective platform for biomolecule detection.
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Affiliation(s)
- Yuanxun Gong
- Guangxi Key Laboratory for Preclinical and Translational Research on Bone and Joint Degenerative Diseases, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China
| | - Danlei Tong
- Graduate School, Guangxi University of Chinese Medicine, Nanning, 530001, China
| | - Ping Qiu
- Graduate School, Guangxi University of Chinese Medicine, Nanning, 530001, China
| | - Rilian Song
- Guangxi Key Laboratory for Preclinical and Translational Research on Bone and Joint Degenerative Diseases, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China
| | - Zhidan Li
- Guangxi Key Laboratory for Preclinical and Translational Research on Bone and Joint Degenerative Diseases, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China
| | - Yanlin He
- Guangxi Key Laboratory for Preclinical and Translational Research on Bone and Joint Degenerative Diseases, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China
| | - Qisheng Luo
- Guangxi Key Laboratory for Preclinical and Translational Research on Bone and Joint Degenerative Diseases, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China
| | - Qianli Tang
- Guangxi Key Laboratory for Preclinical and Translational Research on Bone and Joint Degenerative Diseases, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China; Graduate School, Guangxi University of Chinese Medicine, Nanning, 530001, China.
| | - Kai Zhang
- School of Chemistry and Materials Science, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
| | - Xianjiu Liao
- Key Laboratory of Research on Prevention and Control of High Incidence Diseases in Western Guangxi, Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China.
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Otsuka Y, Ishii M, Ikebe S, Nakamura T, Tsujita K, Kaikita K, Matoba T, Kohro T, Oba Y, Kabutoya T, Kario K, Imai Y, Kiyosue A, Mizuno Y, Nochioka K, Nakayama M, Iwai T, Miyamoto Y, Sato H, Akashi N, Fujita H, Nagai R. BNP level predicts bleeding event in patients with heart failure after percutaneous coronary intervention. Open Heart 2023; 10:e002489. [PMID: 38065584 PMCID: PMC10711837 DOI: 10.1136/openhrt-2023-002489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 11/15/2023] [Indexed: 12/18/2023] Open
Abstract
OBJECTIVE This study aimed to investigate the association between heart failure (HF) severity measured based on brain natriuretic peptide (BNP) levels and future bleeding events after percutaneous coronary intervention (PCI). BACKGROUND The Academic Research Consortium for High Bleeding Risk presents a bleeding risk assessment for antithrombotic therapy in patients after PCI. HF is a risk factor for bleeding in Japanese patients. METHODS Using an electronic medical record-based database with seven tertiary hospitals in Japan, this retrospective study included 7160 patients who underwent PCI between April 2014 and March 2020 and who completed a 3-year follow-up and were divided into three groups: no HF, HF with high BNP level and HF with low BNP level. The primary outcome was bleeding events according to the Global Use of Streptokinase and t-PA for Occluded Coronary Arteries classification of moderate and severe bleeding. The secondary outcome was major adverse cardiovascular events (MACE). Furthermore, thrombogenicity was measured using the Total Thrombus-Formation Analysis System (T-TAS) in 536 consecutive patients undergoing PCI between August 2013 and March 2017 at Kumamoto University Hospital. RESULTS Multivariate Cox regression showed that HF with high BNP level was significantly associated with bleeding events, MACE and all-cause death. In the T-TAS measurement, the thrombogenicity was lower in patients with HF with high BNP levels than in those without HF and with HF with low BNP levels. CONCLUSIONS HF with high BNP level is associated with future bleeding events, suggesting that bleeding risk might differ depending on HF severity.
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Affiliation(s)
- Yasuhiro Otsuka
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Masanobu Ishii
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - So Ikebe
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Taishi Nakamura
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
- Department of Medical Information Science, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Koichi Kaikita
- Division of Cardiovascular Medicine and Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Tetsuya Matoba
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Takahide Kohro
- Department of Clinical Informatics, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Yusuke Oba
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Tomoyuki Kabutoya
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Kazuomi Kario
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Yasushi Imai
- Division of Clinical Pharmacology, Department of Pharmacology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Arihiro Kiyosue
- Department of Cardiovascular Medicine, The University of Tokyo Hospital, Tokyo, Japan
| | - Yoshiko Mizuno
- Department of Cardiovascular Medicine, The University of Tokyo Hospital, Tokyo, Japan
- Development Bank of Japan Inc, Tokyo, Japan
| | - Kotaro Nochioka
- Division of Cardiovascular Medicine, Tohoku University Hospital, Sendai, Japan
| | - Masaharu Nakayama
- Department of Medical Informatics, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Takamasa Iwai
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Yoshihiro Miyamoto
- Open Innovation Center, National Cerebral and Cardiovascular Center, Osaka, Japan
| | | | - Naoyuki Akashi
- Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Hideo Fujita
- Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Ryozo Nagai
- Jichi Medical University School of Medicine, Tochigi, Japan
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Abstract
BACKGROUND Fluid overload is associated with mortality in haemodialysis patients, and 30% of patients remain fluid-overloaded after dialysis. The aim of this study was to evaluate if implementation of Recova®, a decision aid combining clinical assessment with bioimpedance spectroscopy, facilitates individualization of target weight determination and thereby contributes to improved fluid status in maintenance haemodialysis patients. METHODS The impact of the implementation was measured as the proportion of participants at an adequate target weight at the end of the study, assessed as change in symptoms, hydration status, and N-terminal pro-brain natriuretic peptide (NT-proBNP). Nurses were instructed to use Recova every 2 weeks, and the process of the intervention was measured as frequencies of fluid status assessments, bioimpedance measurements, and target weight adjustments. RESULTS Forty-nine patients at two haemodialysis units were enrolled. In participants with fluid overload (n = 10), both overhydration and fluid overload symptom score decreased. In fluid-depleted participants (n = 20), target weight adjustment frequency and the estimated target weight increased. The post-dialytic negative overhydration was reduced, but NT-proBNP increased. CONCLUSIONS Implementation of Recova in haemodialysis care increased the monthly frequencies of bioimpedance measurements and target weight adjustments, and it contributed to symptom reduction. TRIAL REGISTRATION The Uppsala County Council Registry of Clinical Trials: FoU 2019-0001-15.
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Affiliation(s)
- Jenny Stenberg
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
- CONTACT Jenny Stenberg Department of Medical Sciences, Uppsala University, Akademiska Sjukhuset, Entrance 40, Uppsala, 751 85, Sweden
| | - Magnus Lindberg
- Department of Caring Sciences, University of Gävle, Gävle, Sweden
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Hans Furuland
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
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Harpaz D, Koh B, Marks RS, Seet RCS, Abdulhalim I, Tok AIY. Point-of-Care Surface Plasmon Resonance Biosensor for Stroke Biomarkers NT-proBNP and S100β Using a Functionalized Gold Chip with Specific Antibody. Sensors (Basel) 2019; 19:s19112533. [PMID: 31163612 PMCID: PMC6603756 DOI: 10.3390/s19112533] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 05/31/2019] [Accepted: 05/31/2019] [Indexed: 12/22/2022]
Abstract
Surface-plasmon-resonance (SPR) is a quantum-electromagnetic phenomenon arising from the interaction of light with free electrons at a metal-dielectric interface. At a specific angle/wavelength of light, the photon's energy is transferred to excite the oscillation of the free electrons on the surface. A change in the refractive-index (RI) may occur, which is influenced by the analyte concentration in the medium in close contact with the metal surface. SPR has been widely used for the detection of gaseous, liquid, or solid samples. In this study, a functionalized specific SPR chip was designed and used in a novel point-of-care SPR module (PhotonicSys SPR H5) for the detection of the stroke biomarkers NT-proBNP and S100β. These biomarkers have proven to be good for stroke diagnosis, with sensitivity and specificity of >85%. Specific detection was done by binding a biomolecular-recognizing antibody onto the Au SPR-chip. Detection was tested in water and plasma samples. NT-proBNP and S100β were detected in a range of concentrations for stroke, from 0.1 ng/mL to 10 ng/mL. The RI of the blank plasma samples was 1.362412, and the lowest concentration tested for both biomarkers showed a prominent shift in the RI signal (0.25 ng/mL NT-proBNP (1.364215) and S100β (1.364024)). The sensor demonstrated a clinically relevant limit-of-detection of less than ng/mL.
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Affiliation(s)
- Dorin Harpaz
- School of Material Science & Engineering, Nanyang Technology University, 50 Nanyang Avenue, Singapore 639798, Singapore.
- Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- Institute for Sports Research (ISR), Nanyang Technology University and Loughborough University, Nanyang Avenue, Singapore 639798, Singapore.
| | - Brescia Koh
- School of Material Science & Engineering, Nanyang Technology University, 50 Nanyang Avenue, Singapore 639798, Singapore.
| | - Robert S Marks
- Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- The Ilse Katz Centre for Meso and Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
| | - Raymond C S Seet
- Division of Neurology, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 10 Medical Dr, Singapore 117597, Singapore.
| | - Ibrahim Abdulhalim
- School of Material Science & Engineering, Nanyang Technology University, 50 Nanyang Avenue, Singapore 639798, Singapore.
- The Ilse Katz Centre for Meso and Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- Department of Electro optics and Photonics Engineering, Ben Gurion University of the Negev, Beer-Sheva 84105, Israel.
| | - Alfred I Y Tok
- School of Material Science & Engineering, Nanyang Technology University, 50 Nanyang Avenue, Singapore 639798, Singapore.
- Institute for Sports Research (ISR), Nanyang Technology University and Loughborough University, Nanyang Avenue, Singapore 639798, Singapore.
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Krzesiński P, Uziebło-Życzkowska B, Gielerak G, Stańczyk A, Piotrowicz K, Piechota W, Smurzyński P, Skrobowski A. Echocardiographic assessment and N-terminal pro-brain natriuretic peptide in hypertensives with metabolic syndrome. ADV CLIN EXP MED 2017; 26:295-301. [PMID: 28791849 DOI: 10.17219/acem/33554] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND N-terminal pro-brain natriuretic peptide (NT-proBNP) release is associated with left ventricular expansion and pressure overload. Elevation of serum levels of natriuretic peptides is observed in patients with impaired as well as preserved left ventricular systolic function. High NT-proBNP has been shown to be related not only to preload but also to increased afterload, especially blood pressure and arterial stiffness. OBJECTIVES The aim of the study was to evaluate the association of NT-proBNP and echocardiographic parameters in hypertensives with metabolic syndrome. MATERIAL AND METHODS The study group comprised 133 patients (99 men; mean age 45.9 ± 9.4 years) with at least a 3-month history of arterial hypertension (stages 1 and 2) and fulfilling the diagnostic criteria for metabolic syndrome. Following initial clinical assessment, which included NT-proBNP levels, they underwent two-dimensional echocardiography. RESULTS Echocardiographic abnormalities were observed in 60 subjects (45.1%), including left ventricular diastolic dysfunction (LVDdf) in 41 (30.8%) and left ventricular hypertrophy (LVH) in 35 (26.3%). Higher NT-proBNP concentrations were observed in patients with LVH, especially in the presence of LVDdf. Further analysis demonstrated that NT-proBNP correlated negatively with septal E' (r = -0.38; p = 0.015) and heart rate (r = -0.42; p = 0.006) in patients with LVDdf, and positively with left ventricular end diastolic diameter (r = 0.46; p = 0.006) and left ventricular mass index (r = 0.49; p = 0.005) in subjects with LVH. However, the analysis of ROC curves revealed no NT-proBNP level of good sensitivity and specificity in diagnosing LVDdf/LVH (maximal area under the curve 0.571). CONCLUSIONS Even a relatively low NT-proBNP concentration can be a useful marker of left ventricular hypertrophy and end-diastolic wall stretch. However, in the present study there was no NT-proBNP level of satisfactory predictive value to diagnose LV abnormalities.
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Affiliation(s)
- Paweł Krzesiński
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
| | - Beata Uziebło-Życzkowska
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
| | - Grzegorz Gielerak
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
| | - Adam Stańczyk
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
| | - Katarzyna Piotrowicz
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
| | - Wiesław Piechota
- Department of Laboratory Diagnostics, Military Institute of Medicine, Warszawa, Poland
| | - Paweł Smurzyński
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
| | - Andrzej Skrobowski
- Department of Cardiology and Internal Diseases, Military Institute of Medicine, Warszawa, Poland
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Koller L, Richter B, Goliasch G, Blum S, Korpak M, Zorn G, Brekalo M, Maurer G, Wojta J, Pacher R, Hülsmann M, Niessner A. CD4+ CD28(null) cells are an independent predictor of mortality in patients with heart failure. Atherosclerosis 2013; 230:414-6. [PMID: 24075776 DOI: 10.1016/j.atherosclerosis.2013.08.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 04/19/2013] [Accepted: 08/06/2013] [Indexed: 11/18/2022]
Abstract
AIMS Immune activation and subsequent release of proinflammatory cytokines plays a central role in the pathophysiology of chronic heart failure (CHF). Cytotoxic CD4(+)CD28(null) cells are generated under inflammatory conditions and implicated in a variety of pathological processes like atherosclerosis and autoimmune diseases. The study aim was to assess the impact of CD4(+)CD28(null) cells on survival in CHF patients. METHODS AND RESULTS Circulating lymphocytes from 107 CHF patients were analyzed for the distribution of CD4 subsets by flow cytometry. During a median follow-up of 23 months, 22 (20%) persons died. CD4(+)CD28(null) cells independently predicted all-cause mortality with an adjusted hazard ratio (HR) of 1.88 per 1-standard deviation increase (95% confidence interval (CI): 1.26-2.79, P = 0.002) and with a HR of 1.83 for cardiovascular mortality (95% CI: 1.18-2.86, P = 0.008), respectively. Further, we found a significant association with NT-proBNP (r = 0.23). CONCLUSION Circulating CD4(+)CD28(null) cells are associated with CHF severity and are a strong and independent predictor of mortality in CHF fostering the implication of the immune system in CHF pathophysiology.
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Affiliation(s)
- Lorenz Koller
- Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
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Takei Y, Inoue K, Trajanovska S, Donald JA. B-type natriuretic peptide (BNP), not ANP, is the principal cardiac natriuretic peptide in vertebrates as revealed by comparative studies. Gen Comp Endocrinol 2011; 171:258-66. [PMID: 21362425 DOI: 10.1016/j.ygcen.2011.02.021] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2010] [Revised: 02/08/2011] [Accepted: 02/20/2011] [Indexed: 12/31/2022]
Abstract
The natriuretic peptide (NP) family consists of at least seven members; cardiac ANP, BNP and VNP and brain CNPs (CNP1-4). Phylogenetic and comparative genomic analyses showed that CNP4 is the ancestral molecule of the family, from which CNP3 and CNP1/2 were duplicated in this order, and that the three cardiac NPs were generated from CNP3 by tandem duplication. Seven members existed at the divergence of ray-finned fishes and lobe-finned fishes (tetrapods), but some of the NP genes have disappeared during the course of evolution. In ray-finned fishes, all three cardiac NPs exist in chondrostei and some migratory teleost species, but VNP is generally absent and ANP is absent in a group of teleosts (Beloniformes). In tetrapods, ANP and BNP are present in mammals and amphibians, but ANP is usually absent in reptiles and birds. Thus, BNP is a ubiquitous cardiac NP in bony fishes and tetrapods though elasmobranchs and cyclostomes have only CNP3/4 as a cardiac NP. Functional studies indicate that cardiac NPs are essential Na(+)-extruding hormones throughout vertebrates; they play critical roles in seawater (SW) adaptation in teleosts, while they are important volume-depleting hormones in mammals as water and Na(+) are regulated in parallel in terrestrial animals. In mammals, cardiac NPs become prominent in pathological conditions such as heart failure where they are used in diagnosis and treatment. Although the functional role of BNP has not yet been fully elucidated compared with ANP in non-mammalian vertebrates, it appears that BNP plays pivotal roles in the cardiovascular and body fluid regulation as shown in mammals. ANP has previously been recognized as the principal cardiac NP in mammals and teleosts, but comparative studies have revealed that BNP is the only cardiac NP that exists in all tetrapods and teleosts. This is an excellent example showing that comparative studies have created new insights into the molecular and functional evolution of a hormone family.
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Affiliation(s)
- Yoshio Takei
- Laboratory of Physiology, Atmosphere and Ocean Research Institute, University of Tokyo, Chiba 277-8564, Japan.
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Abstract
We applied fluorescence fluctuation spectroscopy to resolve the binding heterogeneity of fluorescently labeled ligand derived from brain natriuretic peptide (BNP), a widely used diagnostic marker of heart failure, to a corresponding monoclonal antibody. This system includes three species: (1) free ligand molecules, (2) antibody with a single site occupied, and (3) antibody with both sites occupied. The method we used, time-integrated fluorescence cumulant analysis (TIFCA), utilizes cumulants of fluorescence fluctuations to resolve subpopulations of multiple fluorescent species freely diffusing in a solution. The values of the cumulants depend on the concentration, molecular brightness and diffusion time of the fluorescent molecules. The number of molecules in each species reflects the antibody affinity. We apply TIFCA to successfully establish the stoichiometry of the system, estimate affinity, and identify the presence of an inactive fraction of antigen in a single titration experiment.
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Dixon RB, Sampson JS, Muddiman DC. Generation of multiply charged peptides and proteins by radio frequency acoustic desorption and ionization for mass spectrometric detection. J Am Soc Mass Spectrom 2009; 20:597-600. [PMID: 19112029 DOI: 10.1016/j.jasms.2008.11.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2008] [Revised: 11/25/2008] [Accepted: 11/25/2008] [Indexed: 05/27/2023]
Abstract
The design and implementation of a radio frequency acoustic desorption ionization (RADIO) source has been demonstrated for the analysis of multiply charged peptides and proteins. One muL aliquots of melittin, BNP-32, and ubiquitin ( approximately 1 mug of analyte) were deposited onto a quartz crystal microbalance (QCM) electrode before radio frequency actuation for desorption. Continuous electrospray parallel to/above the sampling surface enabled the ionization of desorbed species. Detection by a hybrid linear ion trap Fourier transform ion cyclotron resonance mass spectrometer confirmed the intact and dissociated species observed during MS and MS/MS experiments, respectively.
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Affiliation(s)
- R Brent Dixon
- W. M. Keck FT-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA
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10
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Kamberi M, Kim YJ, Jun B, Riley CM. The effects of sucrose on stability of human brain natriuretic peptide [hBNP (1-32)] and human parathyroid hormone [hPTH (1-34)]. ACTA ACUST UNITED AC 2008; 66:348-56. [PMID: 16316450 DOI: 10.1111/j.1399-3011.2005.00290.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although the effect of sucrose on the physical stability of proteins has been well documented, its impact on their chemical stability is largely unknown. The aim of this study was to investigate the potential effects of sucrose on the structural conformation of human brain natriuretic peptide [hBNP (1-32)] and the synthetic human parathyroid hormone [hPTH (1-34)], and link these effects to chemical degradation pathways of these peptides. The stability of hBNP (1-32) and hPTH (1-34) was studied at pH 5.5. Aggregation was monitored using size exclusion high-performance liquid chromatography (SE-HPLC), whereas oxidation and deamidation products were measured by reversed phase (RP) HPLC. Fourier transform infrared (FT-IR) spectroscopy was used to study the peptides' conformation. Sucrose retarded aggregation, deamidation, and oxidation of hBNP (1-32) and hPTH (1-34), with a maximum effect at relatively high concentrations (as much as 1 m). FT-IR spectroscopy indicated that sucrose maintained the native conformation of hBNP (1-32) and induced small conformation changes in the hPTH (1-34) structure. Sucrose enhanced the stability of hBNP (1-32) and hPTH (1-34) in liquid formulations. The stabilizing effect of sucrose was due to a large extent to retardation of oxidation and deamidation of hBNP (1-32) and hPTH (1-34).
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Affiliation(s)
- M Kamberi
- Department of Analytical Sciences, ALZA Corporation, Mountain View, CA 94039-7210, USA.
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Jerczyńska H, Pawłowska Z. [Natriuretic peptides--their receptors and role in cardiovascular system]. Postepy Biochem 2008; 54:35-42. [PMID: 18610580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Natriuretic peptides belong to a family of small proteins that play a major role in modulation of natriuresis, diuresis and vasodilatation. They counteract the activity of renin-angiotensin-aldosterone system. They are also involved in the regulation of homeostasis, fat metabolism and long bone growth. Natriuretic peptides family in mammals consists of three main members: atrial natriuretic peptide (ANP) - secreted by the atrial myocardium; brain natriuretic peptide (BNP)--secreted mainly by the ventricular myocardium, and C-type natriuretic peptide (CNP)--produced and released by endothelial cells. Secretion of these peptides is stimulated by atrial and ventricular distension, increased blood pressure, hypoxia or renal dysfunction. Natriuretic peptides play their roles via interactions with NPR-A and NPR-B receptors which are transmembrane guanylyl cyclases. Their local concentrations, regulated by internalization and degradation, are mediated by the NPR-C receptor and by neutral endopeptidase. The paper presents the current knowledge of structure and biological function of natriuretic peptides.
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Affiliation(s)
- Hanna Jerczyńska
- Katedra i Zakład Biofizyki Molekularnej i Medycznej, Uniwersytet Medyczny w Lodzi, Lódź
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Pereira M, Azevedo A, Severo M, Barros H. Long-term stability of endogenous B-type natriuretic peptide during storage at −20 °C for later measurement with Biosite Triage assay. Clin Biochem 2007; 40:1104-7. [PMID: 17706628 DOI: 10.1016/j.clinbiochem.2007.06.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 05/29/2007] [Accepted: 06/07/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To evaluate the long-term stability of B-type natriuretic peptide (BNP) in frozen samples at -20 degrees C. DESIGN AND METHODS During a health and nutrition survey of a representative sample of the adult population of Porto, Portugal, blood samples were collected in EDTA tubes. Aliquots of plasma were frozen at -20 degrees C until measurement. Subjects with cardiac structural or functional abnormalities or renal dysfunction were excluded. BNP was assessed using a commercial immunofluorescence assay (Triage BNP Test) as a continuous variable (n=340) and in four subgroups selected according to different storage periods: < or =1 month (n=35), 6-12 months (n=80), 20-24 months (n=18) and > or =36 months (n=21). RESULTS Age- and sex-adjusted BNP values, analyzed as a continuous variable, decreased significantly over time of storage. When we stratified in four intervals of storage time, the median BNP value (25th-75th percentile, p value) was: 22.6 pg/mL (8.9-76.2, reference group) for < or =1 month, 19.8 pg/mL (9.5-48.4, p=0.055) for 6-12 months, 15.3 pg/mL (7.5-35.0, p=0.037) for 20-24 months, and 2.5 pg/mL (2.5-10.5, p<0.001) for > or =36 months. CONCLUSIONS BNP is stable at -20 degrees C for 1 year, without protease inhibitors.
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Affiliation(s)
- Marta Pereira
- Department of Hygiene and Epidemiology, University of Porto Medical School, Alameda Prof Hernâni Monteiro, 4200-319 Porto, Portugal.
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13
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Ueno A, Murasaki K, Hagiwara N, Kasanuki H. Increases in circulating T lymphocytes expressing HLA-DR and CD40 ligand in patients with dilated cardiomyopathy. Heart Vessels 2007; 22:316-21. [PMID: 17879023 DOI: 10.1007/s00380-007-0977-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Accepted: 01/26/2007] [Indexed: 02/07/2023]
Abstract
Inflammatory and immunological mechanisms are implicated in the development of idiopathic dilated cardiomyopathy (DCM). Since activated T lymphocytes express surface HLA-DR antigens, an increased level of these cells in the circulation could indicated an ongoing immune response. While the role of activated T lymphocytes in experimental myocarditis has been elucidated, the contribution of T lymphocyte activation in clinical DCM remains unclear. We therefore examined the role of T-cell activation in peripheral blood samples obtained from 10 patients with DCM (mean age, 49 +/- 12 years) and from 10 age-matched healthy controls. Citrated whole blood was mixed with fluorescein isothiocyanate- or phycoerythrin-conjugated specific monoclonal antibodies and analyzed using a fluorescence-activated cell sorter (FACS). The ratio (%) of histocompatibility leukocyte antigen (HLA)-DR positive cells in the FACS gated lymphocyte population was significantly higher in DCM patients than in controls (7.9% +/- 5.3% vs 2.0% +/- 0.9%; P < 0.01). The expression of CD40L on T cells determined as mean fluorescence intensity (MFI) was also significantly higher in DCM patients than in controls (3.6 +/- 2.1 vs 1.8 +/- 0.4 MFI; P < 0.05). Furthermore, the ratios of T cells expressing HLA-DR and serum brain natriuretic peptide (BNP) levels closely correlated (P = 0.0008). We showed that HLA-DR on peripheral T cells significantly correlated with serum BNP levels and that high CD40L expression on T cells was concomitant with increased BNP levels (P < 0.05). Therefore the magnitude of T-cell expression, such as increased expression of HLA-DR and CD40L, contributes to myocardial dysfunction in DCM.
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Affiliation(s)
- Atsuko Ueno
- Department of Cardiology, Tokyo Women's Medical University, Tokyo 162-8666, Japan
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14
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Efthimiadis GK, Hitoglou-Makedou A, Giannakoulas G, Mitakidou A, Karamitsos T, Karvounis H, Mochlas S, Styliadis I, Stefanidis H, Parcharidis G, Louridas G. Clinical significance of N-terminal-probrain natriuretic peptide in hypertrophic cardiomyopathy. Heart Vessels 2007; 22:322-7. [PMID: 17879024 DOI: 10.1007/s00380-007-0976-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Accepted: 01/27/2007] [Indexed: 10/22/2022]
Abstract
N-Terminal-probrain natriuretic peptide (NT-proBNP) plasma levels are elevated in patients with congestive heart failure. Published data concerning the utility of NT-proBNP in hypertrophic cardiomyopathy (HCM) are lacking. Our aim was to evaluate the clinical significance of NT-proBNP in patients with HCM. A blood sample was collected for plasma NT-proBNP measurement from 43 consecutive patients with documented HCM. NT-proBNP was measured using a chemiluminescent immunoassay kit (Roche Diagnostics) on an Elecsys 2010 analyzer. Median value of NT-proBNP was 219 pg/ml (range 8-3 045 pg/ml) in NYHA class I patients, 698 pg/ml (125-2 463 pg/ml) in NYHA class II patients, and 2 683 pg/ml (131-11 542 pg/ml) in NYHA class III and IV patients. NT-proBNP plasma levels were significantly higher across the severity of functional limitation (i.e., NYHA class classification) (P = 0.002). NT-proBNP levels were significantly higher in female than male (P = 0.034), in referral vs nonreferral patients (P = 0.004), in symptomatic vs asymptomatic patients (P = 0.020), in patients with basal subaortic gradient >or=30 mmHg (P = 0.001) and in the patients who were on cardioactive medication (P = 0.010). In univariate analysis NT-proBNP was significantly correlated with age (P < 0.001), left ventricular maximum wall thickness (P = 0.001), left atrial size (P = 0.019), and subaortic gradient >or=30 mmHg (P < 0.001). In multivariate regression analysis, age (P < 0.001), maximum wall thickness (P = 0.007), and gradient >or=30 mmHg (P = 0.027) were independently associated with NT-proBNP levels. Our data support the idea that measurement of plasma NT-proBNP levels in HCM patients is useful to assess their clinical status, especially the severity of hypertrophy and the presence of obstruction, although age must be taken into account.
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Affiliation(s)
- Georgios K Efthimiadis
- First Cardiology Department, AHEPA Hospital, Aristotle University, Thessaloniki, Greece.
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Naka T, Katsumata E, Sasaki K, Minamino N, Yoshioka M, Takei Y. Natriuretic Peptides in Cetaceans: Identification, Molecular Characterization and Changes in Plasma Concentration After Landing. Zoolog Sci 2007; 24:577-87. [PMID: 17867859 DOI: 10.2108/zsj.24.577] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2006] [Accepted: 01/02/2007] [Indexed: 11/17/2022]
Abstract
Dolphins are aquatic animals free from gravity, and this may have imposed significant changes in their cardiovascular status and its hormonal regulation compared with terrestrial animals. This study molecularly characterized two major cardiovascular hormones, atrial and B-type natriuretic peptides (ANP and BNP) and measured their changes in dolphin plasma concentrations in relation to the cardiovascular status of the animal. We initially identified ANP and BNP in three species of dolphins (Lagenorhynchus obliquidens, Phocoenoides dalli and Tursiops truncatus). ANP precursors are highly conserved in most mammals, but dolphin BNP precursors were more variable. In molecular phylogenetic analyses, dolphin ANP and BNP precursors grouped with those of artiodactyls, particularly to the camel peptides. The chromatographic characterization of tissue and plasma molecular forms using specific radioimmunoassays showed that the predominant ANP and BNP in the atrium are prohormone and mature peptide, respectively, whereas mature ANP and BNP are circulating in the dolphin blood. A mass spectrometric analysis showed that atrial BNP consists of 26 amino acids, rather than the 32-amino-acid form detected in other mammals. Finally, changes in plasma ANP and BNP concentrations were examined in captive bottlenose dolphins (Tursiops truncatus) after their pool was drained. Plasma ANP and BNP concentrations did not change after landing, unlike terrestrial mammals. Plasma angiotensin II and cortisol concentrations did not change either, showing minor stress after landing. Since landed dolphins show a different cardiovascular status on land than terrestrial mammals, plasma ANP and BNP concentrations seem to reflect the cardiovascular status characteristic of dolphins.
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Affiliation(s)
- Tadaomi Naka
- Laboratory of Physiology, Ocean Research Institute, University of Tokyo, Nakano, Tokyo, Japan.
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16
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Crimmins DL, Kao JLF. The human cardiac hormone fragment N-terminal pro B-type natriuretic peptide is an intrinsically unstructured protein. Arch Biochem Biophys 2007; 461:242-6. [PMID: 17399679 DOI: 10.1016/j.abb.2007.02.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 02/13/2007] [Accepted: 02/16/2007] [Indexed: 10/23/2022]
Abstract
The cardiac hormone B-type natriuretic peptide (BNP) is synthesized as a prepro 134 residue molecule which is further proteolytically processed into a 76 residue fragment termed N-terminal proBNP (NT-proBNP) and the active portion of this hormone, a 32-residue disulfide-linked peptide (BNP-32). The active hormone regulates cardiac hemodynamic output while as yet no biological function has been attributed to NT-proBNP. Some solution properties of synthetically generated NT-proBNP in benign media are known. The protein is monomeric, elutes aberrantly on size-exclusion chromatography as an apparent larger molecular species, and possesses little global secondary structure as assessed by circular dichroism. To explore the solution structure of NT-proBNP in greater detail, we use 2D-NOESY and 2D-TOCSY NMR on recombinant NT-proBNP to obtain a high resolution solution conformation at the alpha-carbon level. Importantly, NH(i)-NH(i+1) coupling is virtually absent at room temperature implying that large stretches of primary sequence are unordered. Together, the results of these physicochemical measurements classify NT-proBNP as a naturally unfolded protein referred to as an Intrinsically Unstructured Protein (IUP). The calculations of FoldIndex, a computer program which predicts disorder, were compared to the experimental results described here for NT-proBNP in addition to proBNP. NT-proBNP thus appears to be an ideal candidate for the study of native, unfolded proteins.
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Affiliation(s)
- Dan L Crimmins
- Department of Pathology and Immunology, Division of Laboratory Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
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17
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18
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Abstract
OBJECTIVE Serum N-terminal-pro-B-type natriuretic peptide (NT-proBNP) is elevated in systolic heart failure due to volume expansion and pressure overload. Recent data suggest a direct stimulatory effect of thyroid hormones on NT-proBNP synthesis. We examined the influence of acutely induced hyperthyroidism on serum levels of NT-proBNP. DESIGN Forty-three healthy women were evaluated before and after treatment with 60 mug triiodothyronine (T(3)) daily for 7 days in a noncontrolled study. MAIN OUTCOME Before treatment, NT-proBNP was independently and inversely associated with thyrotropin (TSH), (r = -0.34, p = 0.02). T(3) therapy induced an increase in free T(3) (3.3 times, p < 0.0001) and suppression of TSH ( p < 0.0001). Heart rate increased by 14% ( p < 0.0001); weight decreased 0.6 kg ( p < 0.0001). Median NT-proBNP increased from 53 to 66 pg/mL ( p < 0.0001). The increase in NT-proBNP levels was independently associated with increase in free T(3) ( p = 0.05) and with reduction in TSH ( p = 0.04), without any association to the changes in cardiac workload. CONCLUSIONS NT-proBNP is influenced by thyroid function among healthy women, as demonstrated by an inverse association between TSH and NT-proBNP. Induction of an acute hyperthyroid state resulted in an increase in NT-proBNP, which seems to reflect a direct action of T(3) on the NT-proBNP secretion rather than an effect of increased cardiac workload.
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Affiliation(s)
- Marianne Schultz
- Department of Cardiology and Endocrinology E, Frederiksberg University Hospital, Frederiksberg, Denmark.
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19
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Cataliotti A, Chen HH, James KD, Burnett JC. Oral Brain Natriuretic Peptide: A Novel Strategy for Chronic Protein Therapy for Cardiovascular Disease. Trends Cardiovasc Med 2007; 17:10-4. [PMID: 17210472 DOI: 10.1016/j.tcm.2006.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2006] [Revised: 10/16/2006] [Accepted: 10/19/2006] [Indexed: 11/30/2022]
Abstract
In 1956, secretory granules were detected via electron microscopy in the mammalian atria by Kisch. This remarkable discovery signaled the beginning of a new field of research that decades later has lead to the concept of the heart as an endocrine organ and the establishment of the natriuretic peptide (NP) system. In 1981, deBold and colleagues identified from the atrial myocardium the first member of the NP family, atrial NP. Thereafter, new members of this growing family of cardiac hormones were identified and investigated. The successful story of B-type or brain NP (BNP), from its discovery to its use in the diagnosis and prognosis of cardiovascular diseases and later as a tool in the treatment of acute congestive heart failure, have since taken place. However, the use of peptides as chronic therapies has been limited by enzymatic degradation. Chronic administration of BNP, particularly in disease states like hypertension and early heart failure, could be effective as an antihypertensive therapy and in delaying progression of cardiac disease. To date, the use of BNP is limited to patients with acute decompensated heart failure, but new strategies are under investigation to extend the use of chronic BNP in less severe stages of cardiovascular diseases. Innovative technologies have been recently developed that allow protection of proteins from enzymatic degradation, making feasible oral administration of small proteins such as BNP. This review will focus on the potential role of BNP as a new chronic therapeutic strategy in the treatment of cardiovascular diseases and will summarize our recent report of the development and in vivo evaluation of orally active human BNP.
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Affiliation(s)
- Alessandro Cataliotti
- Cardiorenal Research Laboratory and Division of Cardiovascular Diseases, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
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20
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Melanson SEF, Laposata M, Camargo CA, Chen AA, Tung R, Krauser D, Anwaruddin S, Baggish A, Cameron R, Sluss P, Lewandrowski KB, Lee-Lewandrowski E, Januzzi JL. Combination of D-dimer and amino-terminal pro-B-type natriuretic Peptide testing for the evaluation of dyspneic patients with and without acute pulmonary embolism. Arch Pathol Lab Med 2006; 130:1326-9. [PMID: 16948519 DOI: 10.5858/2006-130-1326-codaap] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2006] [Indexed: 11/06/2022]
Abstract
CONTEXT D-dimer concentration can be used to exclude a diagnosis of acute pulmonary embolism. However, clinicians frequently order unnecessary supplemental testing in patients with low concentrations of D-dimer. Elevations in natriuretic peptides have also been described in the setting of pulmonary embolism. OBJECTIVE We investigated the integrative role of D-dimer with amino-terminal pro-B-type natriuretic peptide for the evaluation of patients with and without acute pulmonary embolism. DESIGN Patients were selected for analysis from a previous study in which levels of D-dimer and amino-terminal pro-B-type natriuretic peptide were measured. The presence of pulmonary embolism was determined by computed tomographic angiography. RESULTS The median levels of D-dimer were significantly higher in patients with acute pulmonary embolism. Similarly, the median levels of amino-terminal pro-B-type natriuretic peptide were higher in patients with pulmonary embolism. CONCLUSIONS The Roche Tina-quant D-Dimer immunoturbidimetric assay provides a high negative predictive value and can be used to exclude acute pulmonary embolism in patients with dyspnea. Measurement of amino-terminal pro-B-type natriuretic peptide in addition to D-dimer improves specificity for acute pulmonary embolism without sacrificing negative predictive value. A combination of both markers may offer reassurance for excluding acute pulmonary embolism, and thus avoid redundant, expensive confirmatory tests.
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Affiliation(s)
- Stacy E F Melanson
- Department of Pathology, Division of Clinical Laboratories, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass, USA
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21
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Abstract
B-type natriuretic peptide (BNP) is the first biomarker of proven value in screening for left ventricular dysfunction. The availability of point-of-care testing has escalated clinical interest and the resultant research is defining a role for BNP in the investigation and treatment of critically ill patients. This review was undertaken with the aim of collecting and assimilating current evidence regarding the use of BNP assay in the evaluation of myocardial dysfunction in critically ill humans. The information is presented in a format based upon organ system and disease category. BNP assay has been studied in a spectrum of clinical conditions ranging from acute dyspnoea to subarachnoid haemorrhage. Its role in diagnosis, assessment of disease severity, risk stratification and prognostic evaluation of cardiac dysfunction appears promising, but requires further elaboration. The heterogeneity of the critically ill population appears to warrant a range of cut-off values. Research addressing progressive changes in BNP concentration is hindered by infrequent assay and appears unlikely to reflect the critically ill patient's rapidly changing haemodynamics. Multi-marker strategies may prove valuable in prognostication and evaluation of therapy in a greater variety of illnesses. Scant data exist regarding the use of BNP assay to alter therapy or outcome. It appears that BNP assay offers complementary information to conventional approaches for the evaluation of cardiac dysfunction. Continued research should augment the validity of BNP assay in the evaluation of myocardial function in patients with life-threatening illness.
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Affiliation(s)
- D J Sturgess
- Department of Intensive Care, Princess Alexandra Hospital, University of Queensland, Brisbane, Queensland, Australia
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22
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He XL, Dukkipati A, Garcia KC. Structural determinants of natriuretic peptide receptor specificity and degeneracy. J Mol Biol 2006; 361:698-714. [PMID: 16870210 DOI: 10.1016/j.jmb.2006.06.060] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Revised: 06/22/2006] [Accepted: 06/22/2006] [Indexed: 11/22/2022]
Abstract
Cardiovascular homeostasis and blood pressure regulation are reliant, in part, on interactions between natriuretic peptide (NP) hormones and natriuretic peptide receptors (NPR). The C-type NPR (NPR-C) is responsible for clearance of NP hormones from the circulation, and displays a cross-reactivity for all NP hormones (ANP, BNP, and CNP), in contrast to other NPRs, which are more restricted in their specificity. In order to elucidate the structural determinants for the binding specificity and cross-reactivity of NPR-C with NP hormones, we have determined the crystal structures of the complexes of NPR-C with atrial natriuretic peptide (ANP), and with brain natriuretic peptide (BNP). A structural comparison of these complexes, with the previous structure of the NPR-C/CNP complex, reveals that NPR-C uses a conformationally inflexible surface to bind three different, highly flexible, NP ligands. The complex structures support a mechanism of rigid promiscuity rather than conformational plasticity by the receptor. While ANP and BNP appear to adopt similar receptor-bound conformations, the CNP structure diverges, yet shares sets of common receptor contacts with the other ligands. The degenerate versus selective hormone recognition properties of different NPRs appears to derive largely from two cavities on the receptor surfaces, pocket I and pocket II, that serve as anchoring sites for hormone side-chains and modulate receptor selectivity.
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Affiliation(s)
- Xiao-lin He
- Department of Microbiology & Immunology, Howard Hughes Medical Institute, Stanford University School of Medicine, Fairchild D319, 299 Campus Drive, Stanford, CA 94305-5124, USA
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23
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Schellenberger U, O'Rear J, Guzzetta A, Jue RA, Protter AA, Pollitt NS. The precursor to B-type natriuretic peptide is an O-linked glycoprotein. Arch Biochem Biophys 2006; 451:160-6. [PMID: 16750161 DOI: 10.1016/j.abb.2006.03.028] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Revised: 03/23/2006] [Accepted: 03/24/2006] [Indexed: 10/24/2022]
Abstract
Human pro-B-type natriuretic peptide (proBNP), the precursor for B-type natriuretic peptide (BNP), was expressed in Chinese hamster ovary cells (CHO) and compared by Western blot analysis to BNP cross-reacting material immunoprecipitated from the plasma of heart failure patients. Both recombinant and native forms co-migrated as a diffuse band centered around 25 kDa and were reduced to a 12 kDa species by treatment with a mixture of O-link deglycosylation enzymes. The 108-amino acid CHO-expressed protein was examined by tryptic mapping and LC-MS and found to be an O-linked glycoprotein. Determination of the sites of O-glycosyl addition by blank cycle sequencing of tryptic and Glu-C (Staphylococcus aureus V8 protease) peptides showed that there are seven sites of glycosylation confined to a 36-amino acid residue stretch within the center of the propeptide region. This data is consistent with previous observations of higher molecular weight isoforms of BNP.
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Boriani G, Regoli F, Saporito D, Martignani C, Toselli T, Biffi M, Francolini G, Diemberger I, Bacchi L, Rapezzi C, Ferrari R, Branzi A. Neurohormones and inflammatory mediators in patients with heart failure undergoing cardiac resynchronization therapy: time courses and prediction of response. Peptides 2006; 27:1776-86. [PMID: 16621149 DOI: 10.1016/j.peptides.2006.02.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2005] [Revised: 02/23/2006] [Accepted: 02/23/2006] [Indexed: 10/24/2022]
Abstract
Despite interest in neurohormonal activation as a determinant of prognosis in chronic heart failure (CHF) and as a target for pharmacological treatments, data are lacking on the time-related effects of electrical cardiac resynchronization therapy (CRT) on a broad spectrum of neurohormones and cytokines. The aim of this study was to assess time-courses and extents of changes within the neurohormonal profile of CHF patients treated with CRT. We performed a prospective follow-up study in 32 patients with NYHA class III-IV CHF to investigate the effects of CRT on a broad panel of neurohormones proposed for characterization of CHF patients. Levels of atrial and brain natriuretic peptides (ANP, BNP), epinephrine, norepinephrine, aldosterone, plasma renin activity, IL-6, TNF, soluble receptors sTNFR1 and 2, and chromogranin A were assessed before implantation and after 3 months of CRT; when feasible, measurements were also performed at 1 week, 1 month and 12 months (clinical evaluation, echocardiography and ECG were also performed at each time-point). The results showed that at 3 months improvement in NYHA class and echographically assessed left ventricular (LV) reverse structural remodeling were accompanied by significant reductions versus baseline in ANP and BNP, but not in other neurohormones. Moreover a baseline ANP concentration < or = 150 pg/ml was a good predictor of response to CRT in terms of NYHA class reduction and reverse LV remodeling. In conclusion 3 months of CRT significantly reduce natriuretic peptides concentrations, while values of other neurohormones and inflammatory cytokines are relatively unvaried. A baseline ANP concentration < or = 150 pg/ml might be a clinically useful predictor of medium-term response to CRT.
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Affiliation(s)
- Giuseppe Boriani
- Institute of Cardiology, University of Bologna, Azienda Ospedaliera S.Orsola-Malpighi, Bologna, Italy.
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25
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Davis GK, Bamforth F, Sarpal A, Dicke F, Rabi Y, Lyon ME. B-type natriuretic peptide in pediatrics. Clin Biochem 2006; 39:600-5. [PMID: 16430880 DOI: 10.1016/j.clinbiochem.2005.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2005] [Revised: 11/01/2005] [Accepted: 12/06/2005] [Indexed: 01/16/2023]
Abstract
OBJECTIVES There has been growing interest in the use of serum B-type natriuretic peptide (BNP) and the N-terminal segment of its pro-hormone (NT-proBNP) as biomarkers for cardiac disease. The aim of this review is to summarize the current state of knowledge regarding BNP and NT-proBNP measurement in the pediatric population. DESIGN AND METHODS A computerized literature search on the National Library of Medicine was done and all articles including BNP and pediatrics were selected and discussed. RESULTS The data from several studies suggest that the measurement of BNP may be useful in diagnosing and managing pediatric heart failure, congenital heart disease, cardiac transplantation and patients on chemotherapy. There are difficulties in establishing appropriate reference ranges in children. CONCLUSION There is insufficient evidence for the routine use of BNP or NT-proBNP. Further research to clearly define the clinical utility in the pediatric age group is eagerly anticipated.
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Affiliation(s)
- Gershwin K Davis
- Department of Paraclinical Sciences, Faculty of Medical Sciences, The University of the West Indies, Eric Williams Medical Sciences Complex, Champs Fleurs, Trinidad, West Indies.
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Miller MA, Malkar NB, Severynse-Stevens D, Yarbrough KG, Bednarcik MJ, Dugdell RE, Puskas ME, Krishnan R, James KD. Amphiphilic Conjugates of Human Brain Natriuretic Peptide Designed for Oral Delivery: In Vitro Activity Screening. Bioconjug Chem 2006; 17:267-74. [PMID: 16536455 DOI: 10.1021/bc0501000] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Congestive heart failure (CHF) is a complex syndrome involving altered neurohormonal levels and impaired cardiac and renal function. In recent years, intravenous administration of exogenous human brain-type natriuretic peptide (hBNP) has become an important therapy in treating patients with acutely decompensated CHF. However, reports during the past year suggest that hBNP could play a prominent role in the chronic treatment of CHF patients as well. We are currently developing conjugates of hBNP suitable for oral delivery to provide a patient-friendly treatment option for chronic heart failure patients. In this report, we present in vitro activity results obtained from hBNP conjugates featuring a variety of rationally designed amphiphilic oligomers. Mapping studies revealed that the hydrophobic/hydrophilic balance of the oligomer impacted the regioselectivity of conjugation. Additionally, the regiochemistry and extent of conjugation had a significant impact on activity. Many monoconjugates retained activity comparable to native peptide and are currently under evaluation in subsequent in vivo screens.
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Affiliation(s)
- Mark A Miller
- Nobex Corporation, 617 Davis Drive, Suite 100, Durham, North Carolina 27713, USA
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27
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Brandt I, Lambeir AM, Ketelslegers JM, Vanderheyden M, Scharpé S, De Meester I. Dipeptidyl-peptidase IV converts intact B-type natriuretic peptide into its des-SerPro form. Clin Chem 2005; 52:82-7. [PMID: 16254193 DOI: 10.1373/clinchem.2005.057638] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Analysis of plasma B-type natriuretic peptide (BNP) has suggested the in vivo formation of a truncated form, BNP (3-32), also called des-SerPro-BNP. The objectives of this study were to investigate (a) whether BNP and other natriuretic peptides are truncated by dipeptidyl-peptidase IV (DPP IV/CD26; EC 3.4.14.5) and (b) whether this truncation affects the susceptibility to cleavage by neutral endopeptidase (NEP; EC 3.4.24.11). METHODS Human BNP (1-32), A-type natriuretic peptide 1-28 (ANP 1-28), and related peptides were incubated with purified DPP IV and with human plasma. In addition, BNP (1-32), BNP (3-32), and ANP (1-28) were subjected to hydrolysis by NEP. Cleavage products were analyzed by mass spectrometry. RESULTS BNP (1-32) was cleaved by purified DPP IV with a specificity constant of 0.37 x 10(6) L.mol(-1).s(-1). The DPP IV activity in EDTA-plasma was able to truncate BNP (1-32) ex vivo. Addition of Vildagliptin, a specific DPP IV inhibitor, prevented this truncation in a concentration-dependent manner. Under in vitro circumstances in which ANP was hydrolyzed extensively, BNP (1-32) and BNP (3-32) were very resistant to NEP-mediated cleavage. CONCLUSIONS DPP IV cleaves BNP (1-32) with an efficiency higher than or comparable to several known in vivo substrates of the enzyme. Even after loss of the amino-terminal dipeptide, BNP remains highly resistant to cleavage by NEP.
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Affiliation(s)
- Inger Brandt
- Laboratory of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium
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Inoue K, Sakamoto T, Yuge S, Iwatani H, Yamagami S, Tsutsumi M, Hori H, Cerra MC, Tota B, Suzuki N, Okamoto N, Takei Y. Structural and Functional Evolution of Three Cardiac Natriuretic Peptides. Mol Biol Evol 2005; 22:2428-34. [PMID: 16120806 DOI: 10.1093/molbev/msi243] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Natriuretic peptides (NPs) are a group of hormones playing important roles in cardiovascular and osmoregulatory systems in vertebrates. Among the NP subtypes, atrial NP (ANP), B-type NP (BNP), and ventricular NP (VNP) are circulating hormones expressed exclusively in the heart (cardiac NPs). The constitution of cardiac NPs is variable among species of vertebrates. In order to understand the evolutionary and functional significance of such variation, we performed a systematic survey of cardiac NP cDNAs in nine taxonomically diverse teleosts inhabiting environments of varying salinity. The discovery of the coexistence of the ANP, BNP, and VNP genes in the eel and rainbow trout suggested that the ancestral teleost had all three cardiac NPs. As the VNP cDNA was undetectable in ayu and six species of Neoteleostei, it is possible that VNP was lost before the divergence of Osmeroidei. The ANP gene was also undetectable in the medaka. Thus, only the BNP gene is universal in species examined in the present study. Synthetic medaka BNP preferentially activated two medaka GC-A-type receptors, suggesting that the three cardiac NPs share the same receptor. However, the regulation of BNP expression may be the most strict because ATTTA repeats in the 3'-untranslated region and the dibasic motif in the ring are conserved among teleosts and tetrapods. Linkage analyses in the rainbow trout located ANP, BNP, and VNP genes on the same chromosome, which suggested the generation of the VNP gene by tandem duplication as observed with ANP and BNP genes. If the duplication occurred before the divergence of tetrapods and teleosts, VNP may exist in the tetrapod lineage.
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Affiliation(s)
- Koji Inoue
- Ocean Research Institute, The University of Tokyo, Minamidai, Nakano, Tokyo, Japan.
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Zhou L, Giacherio D, Cooling L, Davenport RD. Use of B-natriuretic peptide as a diagnostic marker in the differential diagnosis of transfusion-associated circulatory overload. Transfusion 2005; 45:1056-63. [PMID: 15987348 DOI: 10.1111/j.1537-2995.2005.04326.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Transfusion-associated circulatory overload (TACO) occurs when the transfusion rate or volume exceeds the capacity of a compromised cardiovascular system. Characteristic symptoms and signs associated with TACO are neither sensitive nor specific. B-natriuretic peptide (BNP) is a 32-amino-acid polypeptide secreted from the cardiac ventricles in response to ventricular volume expansion and pressure overload. This study was performed to explore the usage of BNP in the differential diagnosis of TACO. STUDY DESIGN AND METHODS Pre- and posttransfusion BNP levels were determined in 21 patients with suspected TACO and 19 control patients. The BNP was considered significant if the posttransfusion-to-pretransfusion ratio was at least 1.5 and the posttransfusion BNP level was at least 100 pg per mL. RESULTS The BNP test has a sensitivity and specificity of 81 and 89 percent, respectively, in diagnosis of TACO. It has a positive predictive value of 89 percent, a negative predictive value of 81 percent, and an accuracy of 87 percent. In logistic regression analysis, BNP was found to have significant predictive power independent of other clinical variables in models predicting which patients had TACO. CONCLUSIONS Our study suggests that in patients who present symptoms suggestive of TACO, BNP can be a useful adjunct marker in confirming volume overload as the cause of acute dyspnea and symptoms related to cardiovascular compromise.
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Affiliation(s)
- Lan Zhou
- Deparment of Pathology, The University of Michigan Medical School, University Hospital, Ann Arbor, Michigan 48109-0602, USA.
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Affiliation(s)
- Dan L Crimmins
- Department of Pathology and Immunology, Division of Laboratory Medicine, Washington University School of Medicine, 660 South Euclid Ave., Box 8118, St. Louis, MO 63110, USA.
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31
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Wang W, Ou Y, Shi Y. AlbuBNP, a recombinant B-type natriuretic peptide and human serum albumin fusion hormone, as a long-term therapy of congestive heart failure. Pharm Res 2005; 21:2105-11. [PMID: 15587934 DOI: 10.1023/b:pham.0000048203.30568.81] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE B-type natriuretic peptide (BNP) has been in clinical use for the treatment of decompensated congestive heart failure. However, BNP has a very short half-life in circulation, which limits its application to acute CHF and requires continuous i.v. infusion. To provide superior pharmacological benefits of BNP to other stages of chronic congestive heart failure and to eliminate problems associated with drug delivery via continuous i.v. infusion, we have designed and evaluated AlbuBNP, a long-acting form of BNP by recombinant fusion to human serum albumin for use in chronic congestive heart failure, post-acute follow-up, and postmyocardial infarction. METHODS Human BNP (1-32) was seamlessly fused to mature human serum albumin at N-terminus to create AlbuBNP. The bioactivities of AlbuBNP were evaluated by natriuretic peptide receptor-A mediated cGMP activation assay, hemodynamic responses, and plasma cGMP elevation. The pharmacokinetic properties were determined after single i.v. or s.c. bolus injection in C57/BL6 mice. RESULTS AlbuBNP had approxiamtely the same maximal bioactivity as BNP to activate cGMP in the in vitro NPRA/cGMP assay. The EC50s were 28.4+/-1.2 and 0.46+/-1.1 nM for AlbuBNP and BNP, respectively. In spontaneously hypertensive rats, AlbuBNP lowered both systolic and diastolic blood pressure, having sustainable mean arterial pressure reduction for more than 2 days. Six nmol/kg AlbuBNP i.v. bolus in mice increased plasma cGMP level 5.6-fold over the baseline. The elimination half-life in mice was dramatically increased from 3 min for BNP to 12-19 h for AlbuBNP. CONCLUSIONS AlbuBNP is bioactive and has desired pharmacokinetic properties for long-term use. It has the potential to be further developed as a new therapeutic option for chronic, acute, and post-acute CHF to alleviate symptoms, improve clinical status, and slow the disease progression by sustained drug exposure via infrequent simple subcutaneous injections.
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Affiliation(s)
- Wei Wang
- Human Genome Sciences, Inc, Rockville, Maryland 20850, USA
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Honisko ME, Fink JM, Militello MA, Mauro VF, Alexander KS. Compatibility of argatroban with selected cardiovascular agents. Am J Health Syst Pharm 2005; 61:2415-8. [PMID: 15581266 DOI: 10.1093/ajhp/61.22.2415] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Marcia E Honisko
- College of Pharmacy, The University of Toledo, Toledo, OH 43606, USA
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Abstract
Background and Purpose—
The prognostic value of cardiac troponins and natriuretic peptide in acute ischemic stroke is uncertain. We measured cardiac troponin T (cTnT), cardiac troponin I (cTnI), and N-terminal pro-brain natriuretic peptide (NT-proBNP) at admission in acute ischemic stroke patients without evident myocardial damage.
Methods—
In 174 consecutive patients with MRI-confirmed ischemic stroke, serial measurements of cTnT, cTnI, and NT-proBNP were performed at 3 different time points in the hyperacute phase (at admission, on days 1 and 2). Relation of laboratory values to risk factors, stroke subtype classification, and clinical outcome after 3 months was analyzed.
Results—
The highest proportion of raised parameters was found at day 2 for cTnI in 8 of 103 (7.8%), at day 3 for cTnT in 8 of 174 (4.6%), and NT-proBNP in 114 of 174 (65.5%) patients. Proportion of patients with good outcome was significantly reduced in the group with highest NT-proBNP quartile. However, using multivariate regression analysis, no significant relation to morbidity and mortality was found for cTnT, cTnI, or NT-proBNP. Significant impact on the outcome was detected for lesion size, insular involvement, sex, age, and stroke severity.
Conclusions—
NT-proBNP is raised in nearly two thirds of acute stroke patients, whereas elevated cardiac troponins are found only in a small number of acute ischemic stroke patients. Neither NT-proBNP nor cardiac troponins influence clinical outcome if other risk factors are considered.
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Affiliation(s)
- Thorleif Etgen
- Department of Neurology, Technical University of Munich, Germany.
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Jossart C, Coupal M, McNicoll N, Fournier A, Wilkes BC, De Léan A. Photolabeling Study of the Ligand Binding Domain of Natriuretic Peptide Receptor A: Development of a Model. Biochemistry 2005; 44:2397-408. [PMID: 15709752 DOI: 10.1021/bi048251y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are loop-shaped peptidic hormones that have multiple actions on body fluid homeostasis. Their physiological effects are mediated through the activation of their receptor, natriuretic peptide receptor A (NPRA). This receptor is a member of the membrane guanylyl cyclase family and catalyzes cyclic guanosine monophosphate (cGMP) production following its activation. To map the binding site of human NPRA, we applied the methionine proximity assay method to this receptor. We photolabeled NPRA mutants, presenting a single methionine in the binding domain of the receptor, and used benzoylphenylalanine- (Bpa-) substituted peptides at positions 0, 3, 18, 26, and 28 of the ligand. We identified that the N-terminus of the peptide is interacting with the region between Asp(177) and Val(183) of the receptor. Arg(3) is interacting in the vicinity of Phe(172). Leu(18) binds close to Val(116). Phe(26) binds in the vicinity of His(195), and the C-terminal Tyr(28) is located close to Met(173). We next proceeded with photolabeling of a dual Bpa-substituted peptide and showed that the N-terminus and Leu(18) interact with opposite receptor subunits. On the basis of our results, a molecular model of peptide-bound NPRA was developed by homology modeling with the C-type natriuretic peptide- (CNP-) bound natriuretic peptide receptor C (NPRC) crystal structure. The model has been validated by molecular dynamics simulations. Our work provides a rational basis for interpreting and predicting natriuretic peptide binding to the human NPRA.
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Affiliation(s)
- Christian Jossart
- Département de Pharmacologie, Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
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Cauliez B, Berthe MC, Lavoinne A. [Brain natriuretic peptide: physiological, biological and clinical aspects]. Ann Biol Clin (Paris) 2005; 63:15-25. [PMID: 15689309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Accepted: 10/14/2004] [Indexed: 05/01/2023]
Abstract
Brain natriuretic peptide is one member of the natriuretic peptide family, including also ANP, CNP, DNP and urodilatin. In human, brain natriuretic peptide is mainly secreted by the cardiac ventricles. BNP is synthetized as pre-proBNP form, secondary cleaved in proBNP, itself equimolarly cleaved in BNP and NT-proBNP. The biological action of BNP is mediated by the NPR-A receptor. This peptide is eliminated from the systemic circulation by a neutral endopeptidase and by a clearance receptor (NPR-C). The BNP and NT-proBNP concentrations are measured using automated rapid immunoassay techniques. Plasma concentrations of the two peptides physiologically increase with age and are found to be higher in women than in men. The action of BNP against fluid expansion is explained by its vascular (vasodilatation), renal (diuretic and natriuretic) and cerebral activities. The measurement of these two peptides contributes to the diagnosis of heart failure. These peptides are prognostic markers both in heart failure and in acute coronary syndromes. In renal insufficiency, the interpretation of the increase in these two peptide concentrations may be difficult, particularly with the NT-proBNP which is mainly excreted by the kidneys.
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Affiliation(s)
- B Cauliez
- Laboratoire de biochimie médicale, Hôpital Charles Nicolle, CHU Rouen.
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Abstract
AbstractBackground: Since the discovery of cardiac hormones almost 25 years ago, a vast amount of clinical research has identified the cardiac natriuretic peptides and their precursors as markers of heart failure. It even seems likely that the pro-B-type natriuretic peptide (proBNP)-derived peptides in plasma may become the most frequently measured peptides in the daily diagnosis and control of therapy. In contrast, the biochemistry of the peptides has received less attention.Methods: Published data available on the National Library of Medicine (NLM) were used as the basis for the review.Outcome: This review shows that the present understanding of the biochemistry of peptides is far from complete. In particular, cellular synthesis, including posttranslational precursor maturation, is poorly understood. Moreover, elimination of the precursor fragments is unknown. Elucidation of the molecular heterogeneity of proBNP products will therefore contribute to the understanding of the endocrine heart and may also have important diagnostic consequences. Above all, the different proBNP-derived peptides may not always be equal markers of the same pathophysiologic processes. A different metabolism and peripheral elimination may also impose new and peptide-specific limitations for diagnostic use.Conclusions: It is necessary to focus more on the biology of the proBNP-derived peptides. In turn, new insight into the biochemistry could pave the way for more sensitive and disease-specific assays in the clinical setting.
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Affiliation(s)
- Jens Peter Goetze
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100, Denmark.
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Affiliation(s)
- Ronald J Elin
- Department of Pathology and Laboratory Medicine, School of Medicine, University of Louisville, Louisville, Ky 40202, USA.
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Abdulla J, Køber L, Torp-Pedersen C. Methods of Assessing the Functional Status of Patients with Left Ventricular Systolic Dysfunction in Interventional Studies: Can Brain Natriuretic Peptide Measurement be Used as Surrogate for the Traditional Methods? Cardiovasc Drugs Ther 2004; 18:219-24. [PMID: 15229390 DOI: 10.1023/b:card.0000033643.93393.46] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AIM To review whether brain natriuretic peptides (BNP) can be used as a surrogate for the traditional methods of assessing functional status in interventional studies of patients with left ventricular systolic dysfunction (LVSD). METHODS AND RESULTS The traditional methods for assessing functional status including New York Heart Association (NYHA) class, exercise intolerance and quality of life were reviewed in relation to BNP measurements in patients with LVSD. A meta-analysis of four studies evaluating BNP levels versus exercise peak oxygen uptake or 6-minute walking distance showed a significant correlation, but a low R-value of -0.59. Studies using BNP levels for optimisation of heart failure therapy showed conflicting results concerning the correlation between the functional improvement and changes in BNP levels. Conflicting results were also found concerning the utility of BNP levels as a surrogate to predict efficacy of the various anti-congestive therapies on heart failure outcome. CONCLUSION The results of the studies examining BNP measurement as a surrogate for functional status and drug efficacy in patients with LVSD are conflicting. Further studies are necessary to settle the place of BNP measurement as surrogate marker for exercise tolerance, NYHA classification and in assessing efficacy of different interventions in the clinical trials.
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Affiliation(s)
- Jawdat Abdulla
- Department of Cardiology, Gentofte University Hospital, Copenhagen, Denmark.
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Prontera C, Emdin M, Zucchelli GC, Ripoli A, Passino C, Clerico A. Analytical performance and diagnostic accuracy of a fully-automated electrochemiluminescent assay for the N-terminal fragment of the pro-peptide of brain natriuretic peptide in patients with cardiomyopathy: comparison with immunoradiometric assay methods for brain natriuretic peptide and atrial natriuretic peptide. ACTA ACUST UNITED AC 2004; 42:37-44. [PMID: 15061378 DOI: 10.1515/cclm.2004.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractWe evaluated the analytical performance of a fully-automated electrochemiluminescence “sandwich” immunoassay method for the N-terminal fragment of the pro-peptide of brain natriuretic peptide (BNP). We then compared the diagnostic accuracy of this method in discriminating between normal subjects and patients with cardiomyopathy with that found with two previously described immunoradiometric assay methods for the assay of atrial natriuretic peptide (ANP) and BNP. We studied 193 consecutive patients (mean age 64.4±12.3 years, range 20–89 years, including 56 women and 137 men) with chronic cardiomyopathy and a group of 85 healthy subjects (mean age 52.3±12.0 years, 42 women and 43 men, range 20–79 years). N-terminal fragment of proBNP
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40
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Storti S, Prontera C, Emdin M, Passino C, Prati P, Fontani G, Giannelli I, Zyw L, Vittorini S, Zucchelli G, Clerico A. Analytical performance and clinical results of a fully automated MEIA system for brain natriuretic peptide assay: comparison with a point of care testing method. ACTA ACUST UNITED AC 2004; 42:1178-85. [PMID: 15552278 DOI: 10.1515/cclm.2004.238] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe aim of this study was to evaluate the analytical performance of a recently available immunoassay for brain natriuretic peptide (BNP), based on microparticle enzyme immunoassay (MEIA, AxSYM System, Abbott Laboratories), whose analytical characteristics and clinical results were compared with those of a point of care testing (POCT) method (TRIAGE system, Biosite Diagnostics). The within-run and total imprecision of the MEIA system were 18.4% and 19.8% at 21 ng/l, 8.0% and 14.8% at 183 ng/l, and 5.7% and 14.0% at 319 ng/l, respectively. The detection limit of the MEIA system was tested by repeatedly measuring (n = 20) the 0 calibrator in four different runs; a mean +3 SD value of 5.6 ± 4.8 ng/l (range 1.8–12.6 ng/l) was obtained. A close linear relationship (MEIA = –22.5 + 1.71 POCT method, R = 0.950, n = 296) was found (BNP concentration: 5–5500 ng/l), with a significant bias (mean difference: 164.8 ng/l, p < 0.0001). Mean BNP concentration measured in 94 reference subjects (57 women and 37 men; mean age 43.5 ± 14.0 years) was higher with MEIA than POCT, (25.9 ± 32.7 ng/l vs. 11.7 ± 8.9 ng/l, p < 0.0001). The same trend was observed also in 202 cardiac patients (620.6 ± 1082.2 ng/l vs. 386.1 ± 594.5 ng/l, p < 0.0001). Our data suggest that MEIA and POCT have quite similar analytical performance but different clinical results. Then, different reference values, as well as cut-off values, should be taken into account for the clinical use of these two immunoassays.
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Affiliation(s)
- Simona Storti
- Laboratory of Cardiovascular Endocrinology, CNR Institute of Clinical Physiology, Pisa, Italy.
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Tereshchenko SN, Pavlikova EP, Meraĭ IA, Moiseev VS. [Brain natriuretic peptide and heart failure]. Kardiologiia 2003; 42:57-62. [PMID: 12494098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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42
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Collins SP, Ronan-Bentle S, Storrow AB. Diagnostic and prognostic usefulness of natriuretic peptides in emergency department patients with dyspnea. Ann Emerg Med 2003; 41:532-45. [PMID: 12658254 DOI: 10.1067/mem.2003.113] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
More than 4.5 million Americans have congestive heart failure (CHF), close to 550,000 new cases are diagnosed each year, and one third of known patients with CHF are annually admitted to the hospital. Emergency department diagnosis of CHF is often based on history and physical examination findings along with results of ancillary tests, such as chest radiography and ECG. Although signs and symptoms of fluid overload, such as lower extremity edema and dyspnea, raise the suspicion of CHF, their lack of sensitivity makes them poor screening tools. The natriuretic peptides are promising markers of myocardial dysfunction and heart failure. Because of their relationship to myocardial pressure and stretching, natriuretic peptides have been investigated over the past 5 decades as both diagnostic and prognostic markers in acute coronary syndromes and CHF. This article discusses each of the natriuretic peptides and attempts to delineate their potential diagnostic and prognostic roles in the ED.
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Affiliation(s)
- Sean P Collins
- Department of Emergency Medicine, University of Cincinnati, Cincinnati, OH, USA.
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Abstract
The natriuretic peptides are a group of structurally related but genetically distinct peptides. Four types of natriuretic peptides have been found thus far: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP) and Dendroaspis natriuretic peptide (DNP). ANP and BNP are secreted mainly from the heart and function as hormones with vasodilatory and natriuretic effects. CNP originates mainly from endothelial cells with a paracrine effect to induce vasodilation. Other effects of natriuretic peptides including negative inotropy, antimitogenic and anticoagulation have been described. Three types of natriuretic peptide receptors mediate their functions, and among them two are cGMP-coupled. Clearance of natriuretic peptides is via its clearance receptor through the action of neutral endopeptidases. Natriuretic peptides interact with other vasoactive peptides including endothelin. The putative role of natriuretic peptides in the pathophysiology of various cardiovascular diseases including congestive heart failure, hypertension, ischemic heart disease, and cardiomyopathy are discussed. Natriuretic peptide plasma levels are used for the diagnosis and therapeutic follow-up of congestive heart failure patients. Increasing the levels of natriuretic peptides by natriuretic peptide mimetics and neutral endopeptidase inhibitors may provide a new therapeutic strategy for the treatment of cardiovascular diseases such as congestive heart failure and hypertension.
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Affiliation(s)
- Bo Han
- Department of Cardiology, Poriyya Medical Center, Tiberias, POB 15208, Israel
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Abstract
BACKGROUND Brain natriuretic peptide (BNP) is a vasoreactive peptide hormone, which is synthesized and secreted mainly from the heart ventricles. METHODS Molecular forms of immunoreactive human brain natriuretic peptide (BNP) were examined. Chemically synthesized human BNP was added to whole blood samples from a healthy volunteer. The immunoreactive peptide was recovered by immunoaffinity chromatography followed by reversed-phase HPLC (RP-HPLC). Molecular form of immunoreactive BNP in plasma from heart failure patients was also examined. RESULTS Sequential analysis and amino acid analysis of the peptide revealed that two amino acid residues were deleted from the amino terminus of BNP. When roughly classified according to molecular weight (MW), two forms of BNP (high-MW BNP and low-MW BNP) were observed. The estimated MW of high-MW BNP (36 kDa) was three times that of pro-BNP (12 kDa). CONCLUSIONS Analysis of low-MW BNP by RP-HPLC revealed that a small amount of BNP 1-32 or des-SerPro-BNP (BNP 3-32) was contained in plasma from heart failure patients.
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Affiliation(s)
- Hiroyuki Shimizu
- Diagnostics Department, Shionogi & Co., Ltd., 2-5-1 Mishima, Settsu, Osaka 566-0022, Japan.
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Mair J, Hammerer-Lercher A, Puschendorf B. The impact of cardiac natriuretic peptide determination on the diagnosis and management of heart failure. Clin Chem Lab Med 2001; 39:571-88. [PMID: 11522102 DOI: 10.1515/cclm.2001.093] [Citation(s) in RCA: 149] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The long-predicted endocrine function of the heart has been proven by the discovery of atrial natriuretic peptide (atrial natriuretic factor, A-type natriuretic peptide; ANP) 20 years ago. This subsequently led to the description of a whole family of structurally similar but genetically distinct peptides, the natriuretic peptide family, which contributes to cardiovascular homeostasis. These looped peptides promote natriuresis and diuresis, act as vasodilators, and exert antimitogenic effects on cardiovascular tissues. Two members, ANP and brain natriuretic peptide (B-type natriuretic peptide; BNP) are secreted by the heart mainly in response to myocardial stretch induced by volume load. The natriuretic peptides are synthesized as preprohormones. The C-terminal endocrinological active peptides (ANP, BNP) and their N-terminal prohormone fragments are found in plasma. The natriuretic peptide system is activated to its highest degree in ventricular dysfunction. However, natriuretic peptides are increased in all patients with edematous disorders which lead to an increase in atrial tension or central blood volume, such as renal failure or ascitic liver cirrhosis. It could be demonstrated that in chronic heart failure patients and during the subacute phase of myocardial infarction, of all tested neurohormones, the cardiac natriuretic peptides were best markers to identify heart failure and the most powerful predictors of morbidity and mortality. Natriuretic peptides are independent markers for risk assessment. In comparative studies BNP was superior to ANP and its N-terminal prohormone fragments in myocardial infarction as well as in chronic heart failure patients. Less data on N-terminal proBNP (NT-proBNP) is available, but BNP and NT-proBNP appear to be equivalent markers. For primary care physicians natriuretic peptide measurement is useful to decide which patient with suspected heart failure warrants further investigation, particularly when assessment of left ventricular function is not readily available. Natriuretic peptides have an excellent negative predictive value, particularly in high risk patients. An increase in BNP is serious enough to warrant follow-up examinations. For the cardiologists the natriuretic peptides are helpful for guidance of therapy and monitoring disease course in heart failure patients and for risk stratification in heart failure and myocardial infarction.
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Affiliation(s)
- J Mair
- Department of Internal Medicine, University of Innsbruck School of Medicine, Austria.
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Asano K, Murakami M, Endo D, Kimura T, Fujinaga T. Complementary DNA cloning, tissue distribution, and synthesis of canine brain natriuretic peptide. Am J Vet Res 1999; 60:860-4. [PMID: 10407480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE To determine complimentary DNA (cDNA) sequence and tissue distribution of canine brain natriuretic peptide (BNP), and to investigate whether synthesis of canine BNP increases in association with cardiovascular dysfunction. ANIMALS 5 healthy adult mixed-breed dogs and 3 healthy adult Beagles. PROCEDURE Total RNA was extracted from normal canine hearts and was used in a reverse transcription-polymerase chain reaction (RT-PCR) procedure to isolate canine BNP cDNA. Sequence of the isolated cDNA was analyzed. Gene expression of canine BNP in various tissues from 2 mixed-breed dogs was investigated, using RT-PCR and northern blot analyses. Moreover, messenger RNA (mRNA) expression of canine BNP, using northern blot analysis, was compared between grossly normal hearts from 3 Beagles and hearts from 3 mixed-breed dogs with acute myocardial infarction created by surgical ligation. RESULTS The cDNA sequence and deduced amino acid residues of canine BNP precursor were 420 base pairs and 140 residues, respectively. Messenger RNA expression of canine BNP was detectable in the atria but not in the ventricles and the other tissues. Messenger RNA expression of canine BNP was, however, detectable in the infarcted portion of the ventricles. The amount of canine BNP mRNA in the infarcted ventricles was significantly increased, compared with that of noninfarcted ventricles. CONCLUSION The cDNA sequence of canine BNP was determined. Expression of canine BNP mRNA was detected not only in the atria but also in infarcted ventricles. Synthesis of canine BNP increases in association with ischemic myocardial injury. Canine BNP may be used as an indicator of severity of ventricular myocardial injury.
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Affiliation(s)
- K Asano
- Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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Abstract
The natriuretic peptides (NPs) play an important role in the homeostasis of blood pressure and sodium balance in all mammals studied to date. Their combined actions on the vasculature, kidneys, and adrenals reduce blood pressure and intravascular volume. In order to provide sequence information about the ovine NP genes for our physiological studies in sheep, we have determined the genomic DNA sequence of each of the NPs; atrial NP, brain NP (BNP), and C-type NP using an ovine genomic library. Strong homology with other species was found for ovine peptide and genomic sequences of atrial NP and for C-type NP. Further, despite previous reports of poor conservation of BNP across species, the peptide sequence for ovine BNP was found to be identical to both the 26 amino acid-residue porcine BNP, and the 35 amino acid peptide known as bovine aldosterone secretion-inhibitory factor. This data also revealed strong homology of BNP mature forms in dog, cow, pig, and sheep, thus permitting the use of porcine antisera to study BNP-level changes in sheep models of cardiac failure. This conservation of the BNP gene sequence suggests that BNP, like the other NPs, plays an important role in mammalian physiology.
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Affiliation(s)
- G D Aitken
- Department of Medicine, Christchurch School of Medicine, New Zealand.
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Abstract
Natriuretic peptides (NP) act as ligands on the guanylyl cyclase family of receptors. The NP binding site on these receptors is extracellular and the guanylyl cyclase and protein kinase domains are intracellular. The guanylyl cyclase receptor catalyzes the synthesis of the second messenger molecule, cGMP, which activates protein kinase. This in turn is involved in the phosphorylation of various ion transport proteins. Ion transport proteins, which are modulated by NP and are thought to underlie the natriuretic and diuretic actions of NP, include: (a) calcium-activated K+ channels; (b) ATP-sensitive K+ channels; (c) inwardly-rectifying K+ channels; (d) outwardly-rectifying K+ channels; (e) L-type Ca2+ channels; (f) Cl- channels including cystic fibrosis transmembrane conductance regulator Cl- channels; (g) Na+- K+ 2Cl- co-transporter; (h) Na+- K+ ATPase; (i) Na+ channels; (j) stretch-activated channels; and (k) water channels. It appears that NP modulate the kinetics, rather than the conductance, of ion channels. Some of these channels, like the Ca2+, ATP-sensitive K+ and stretch-activated channels, are also involved in NP secretion. In addition, the structural properties of the NP, e.g., ovCNP-22 and ovCNP-39, appear to confer on them the ability to form ion channels. These CNP-formed ion channels can modify the trans-membrane signal transduction and second messenger systems underlying NP-induced pathological effects.
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Affiliation(s)
- J I Kourie
- Department of Chemistry, The Faculties, The Australian National University, Canberra City, ACT.
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Hileman RE, Jennings RN, Linhardt RJ. Thermodynamic analysis of the heparin interaction with a basic cyclic peptide using isothermal titration calorimetry. Biochemistry 1998; 37:15231-7. [PMID: 9790687 DOI: 10.1021/bi980212x] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Brain natriuretic peptide (BNP) was examined as part of a continuing study of the interaction of proteins and peptides with the glycosaminoglycan heparin. BNP was tentatively identified as a heparin-binding protein on the basis of its cyclic structure and the high frequency of the basic amino acid residues, lysine and arginine. Thermodynamic analysis using isothermal titration calorimetry confirmed heparin binding to BNP with a micromolar Kd. Surprisingly, despite the high frequency (22%) of basic residues in BNP, only a small portion of the free energy of this interaction resulted from ionic contributions under physiologic conditions. The contribution of polar amino acids, representing 28% of BNP, was next examined in a variety of different buffers. These experiments demonstrated the transfer of five protons from buffer to BNP on heparin binding, suggesting that hydrogen bonding between the polar residues of BNP and heparin is a major factor contributing to the free energy of BNP binding to heparin. Hydrophobic forces apparently play only a small role in binding. Heparin contains few nonpolar functional groups, and a positive change in heat capacity (DeltaCp = 1 kcal/mol) demonstrates the loss of polar residues on BNP-heparin binding.
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Affiliation(s)
- R E Hileman
- Division of Medicinal and Natural Products Chemistry, Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City 52242, USA
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Buckley MG, Marcus NJ, Yacoub MH, Singer DR. Prolonged stability of brain natriuretic peptide: importance for non-invasive assessment of cardiac function in clinical practice. Clin Sci (Lond) 1998; 95:235-9. [PMID: 9730841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
1.BNP and ANP are important research indices of severity of heart failure. However, uncertainty regarding the stability of these peptides at room temperature has limited their use to assess cardiac function in routine clinical practice. 2. We assessed the stability of BNP and ANP in blood samples left for 2 h or 2 days at room temperature compared with levels in blood processed immediately (initial). These times were chosen to reflect possible times for samples to be processed in a hospital outpatient clinic (2 h) or a blood sample posted to a laboratory from general practice (2 days). Samples were obtained from eight heart transplant recipients. Blood was separated and plasma stored immediately after collection (initial) and after 2 h or 2 days at room temperature respectively. 3. Initial plasma BNP and ANP values measured by radioimmunoassay after Sep-Pak extraction were 38.9+/-11.1(S.E.M.) pg/ml and 113.6+/-28.1 pg/ml, respectively. After 2 h at room temperature there was no significant fall in either peptide level (35.5+/-9.9 pg/ml, BNP; 104. 9+/-30.6 pg/ml, ANP). However, after 2 days at room temperature there was a significant fall in ANP to 38.1+/-12.6 pg/ml (P<0.005 versus initial level). In contrast, there was no significant fall in BNP after 2 days (32.0+/-8.4 pg/ml). After 2 days at room temperature only 30.4+/-4.3% of the ANP remained, but 86.0+/-5.0% of BNP compared with the initial ANP and BNP measurements. 4. Our study clearly showed that ANP is stable for 2 h and thus could be useful as a screening test for heart disease in hospital. In contrast, BNP remained stable for 2 days. Measuring BNP may thus be practical as a test of heart function both for routine use in hospital and by general practitioners in the community.
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Affiliation(s)
- M G Buckley
- Heart Science Centre, National Heart and Lung Institute of Imperial College School of Medicine, Harefield, Middlesex UB9 6JH, U.K
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