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Xu J, Chen WJ, Hu HB, Xie ZW, Zhang DG, Zhao J, Xiang J, Wei QY, Tidwell T, Girard O, Ma FH, Li ZW, Ren YM. A global view on quantitative proteomic and metabolic analysis of rat livers under different hypoxia protocols. Heliyon 2024; 10:e37791. [PMID: 39381102 PMCID: PMC11456861 DOI: 10.1016/j.heliyon.2024.e37791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Revised: 08/01/2024] [Accepted: 09/10/2024] [Indexed: 10/10/2024] Open
Abstract
Hypobaric hypoxia causes altitude sickness and significantly affects human health. As of now, focusing on rats different proteomic and metabolic changes exposed to different hypoxic times at extreme altitude is blank. Our study integrated in vivo experiments with tandem mass tag (TMT)- and gas chromatography time-of-flight (GC-TOF)-based proteomic and metabolomic assessments, respectively. Male Sprague-Dawley rats were exposed to long-term constant hypoxia for 40 days or short-term constant hypoxia for three days, and their responses were compared with those of a normal control group. Post-hypoxia, serum marker assays related to lipid metabolism revealed significant increases in the levels of low-density lipoprotein (LDL), triglycerides (TG), and total cholesterol (TC) in the liver. In contrast, high-density lipoprotein (HDL) levels were upregulated in the long-term constant hypoxia cohorts and were significantly reduced in the short-term constant hypoxia cohorts. Furthermore, metabolic pathway analysis indicated that glycerolipid and glycerophospholipid metabolisms were the most significantly affected pathways in long-term hypoxia group. Subsequently, RT-qPCR analyses were performed to corroborate the key regulatory elements, including macrophage galactose-type lectin (MGL) and Fatty Acid Desaturase 2 (FADS2). The results of this study provide new information for understanding the effects of different hypobaric hypoxia exposure protocols on protein expression and metabolism in low-altitude animals.
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Affiliation(s)
- Jin Xu
- Qinghai University, Xining, 810001, China
| | | | | | | | | | - Jia Zhao
- Qinghai University, Xining, 810001, China
| | - Jing Xiang
- Qinghai University, Xining, 810001, China
| | - Qi-yu Wei
- Qinghai University, Xining, 810001, China
| | - Tawni Tidwell
- Center for Healthy Minds, University of Wisconsin-Madison, 625 Washington Ave, Madison, WI, 53711, USA
| | - Olivier Girard
- School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Crawley, Western Australia, Australia
| | - Fu-hai Ma
- Qinghai Institute of Sports Science, Xi Ning, China
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Pan Z, Hu Y, Huang Z, Han N, Li Y, Zhuang X, Yin J, Peng H, Gao Q, Zhang W, Huang Y, Cui Y, Bi Y, Xu ZZ, Yang R. Alterations in gut microbiota and metabolites associated with altitude-induced cardiac hypertrophy in rats during hypobaric hypoxia challenge. SCIENCE CHINA. LIFE SCIENCES 2022; 65:2093-2113. [PMID: 35301705 DOI: 10.1007/s11427-021-2056-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 01/04/2022] [Indexed: 02/08/2023]
Abstract
The gut microbiota is involved in host responses to high altitude. However, the dynamics of intestinal microecology and their association with altitude-related illness are poorly understood. Here, we used a rat model of hypobaric hypoxia challenge to mimic plateau exposure and monitored the gut microbiome, short-chain fatty acids (SCFAs), and bile acids (BAs) over 28 d. We identified weight loss, polycythemia, and pathological cardiac hypertrophy in hypoxic rats, accompanied by a large compositional shift in the gut microbiota, which is mainly driven by the bacterial families of Prevotellaceae, Porphyromonadaceae, and Streptococcaceae. The aberrant gut microbiota was characterized by increased abundance of the Parabacteroides, Alistipes, and Lactococcus genera and a larger Bacteroides to Prevotella ratio. Trans-omics analyses showed that the gut microbiome was significantly correlated with the metabolic abnormalities of SCFAs and BAs in feces, suggesting an interaction network remodeling of the microbiome-metabolome after the hypobaric hypoxia challenge. Interestingly, the transplantation of fecal microbiota significantly increased the diversity of the gut microbiota, partially inhibited the increased abundance of the Bacteroides and Alistipes genera, restored the decrease of plasma propionate, and moderately ameliorated cardiac hypertrophy in hypoxic rats. Our results provide an insight into the longitudinal changes in intestinal microecology during the hypobaric hypoxia challenge. Abnormalities in the gut microbiota and microbial metabolites contribute to the development of high-altitude heart disease in rats.
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Affiliation(s)
- Zhiyuan Pan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Yichen Hu
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Zongyu Huang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Ni Han
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Yan Li
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Xiaomei Zhuang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Jiye Yin
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Hui Peng
- Tianjin Institute of Environmental & Operational Medicine, Tianjin, 300050, China
| | - Quansheng Gao
- Tianjin Institute of Environmental & Operational Medicine, Tianjin, 300050, China
| | - Wenpeng Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Yong Huang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Yujun Cui
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Yujing Bi
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.
| | - Zhenjiang Zech Xu
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China. .,Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China.
| | - Ruifu Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.
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Daily Chronic Intermittent Hypobaric Hypoxia Does Not Induce Chronic Increase in Pulmonary Arterial Pressure Assessed by Echocardiography. Can Respir J 2018; 2018:9649716. [PMID: 29808103 PMCID: PMC5902055 DOI: 10.1155/2018/9649716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 02/25/2018] [Indexed: 11/17/2022] Open
Abstract
Chronic hypoxia causes pulmonary vascular remodeling resulting in persistently increased pulmonary arterial pressures (PAP) even after return to normoxia. Recently, interest in chronic intermittent hypobaric hypoxia (CIHH) was raised because it occurs in subjects working at high altitude (HA) but living in lowland. However, effects of daily CIHH on PAP are unknown. In this pilot study, we included 8 healthy subjects working at (2650 m) each workday for 8-9 h while living and sleeping at LA and 8 matched control subjects living and working at LA. Cardiorespiratory measurements including echocardiography at rest and during exercise were performed at LA (Munich, 530 m) and HA (Zugspitze, 2650 m). Hemoglobin was higher in CIHH subjects. LA echocardiography showed normal right and left cardiac dimensions and function in all subjects. Systolic PAP (sPAP) and tricuspid annular plane systolic excursion (TAPSE) at rest were similar in both groups. Resting blood gas analysis (BGA) at HA revealed decreased pCO2 in CIHH compared to controls (HA: 28.4 versus 31.7 mmHg, p=0.01). During exercise, sPAP was lower in CIHH subjects compared to controls (LA: 28.7 versus 35.3 mmHg, p=0.02; HA: 26.3 versus 33.6 mmHg, p=0.04) and peripheral oxygen saturation (SpO2) was higher. In sum, subjects exposed to CIHH showed no signs of pulmonary vascular remodeling.
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Rivers EP, McCord J, Otero R, Jacobsen G, Loomba M. Clinical Utility of B-Type Natriuretic Peptide in Early Severe Sepsis and Septic Shock. J Intensive Care Med 2016; 22:363-73. [DOI: 10.1177/0885066607307523] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
B-type natriuretic peptide (BNP) has diagnostic, therapeutic, and prognostic utility in critically ill patients. For severe sepsis and septic shock patients in particular, similar clinical utility from the most proximal aspects of hospital presentation to the intensive care unit has not been examined. BNP levels were measured at 0, 3, 6, 12, 24, 36, 48, 60, and 72 hours in 252 patients presenting to the emergency department with severe sepsis and septic shock. The clinicians were blinded to the BNP levels. Elevated BNP levels (>100 pg/mL) were seen in 42% and 69% of patients on presentation and at 24 hours, respectively. Elevated BNP ranges (>230 pg/mL) were significantly associated with myocardial dysfunction and severity of global tissue hypoxia. When adjusted for age, gender, history of heart failure, renal function, organ dysfunction, and mean arterial pressure, a BNP greater than 210 pg/mL at 24 hours was the most significant independent indicator of increased mortality: odds ratio 1.061 (1.026-1.097), P < .001, 95% confidence interval. Patients with severe sepsis and septic shock often have elevated BNP levels, which are significantly associated with organ and myocardial dysfunction, global tissue hypoxia, and mortality. Serial BNP levels may be a useful adjunct in the early detection, stratification, treatment, and prognostication of high-risk patients.
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Affiliation(s)
- Emanuel P. Rivers
- Department of Emergency Medicine, Henry Ford Hospital, Wayne State University, Detroit, Michigan, Department of Surgery, Henry Ford Hospital, Wayne State University, Detroit, Michigan,
| | - James McCord
- Department of Cardiology, Henry Ford Hospital, Wayne State University, Detroit, Michigan
| | - Ronny Otero
- Department of Emergency Medicine, Henry Ford Hospital, Wayne State University, Detroit, Michigan
| | - Gordon Jacobsen
- Department of Biostatistics and Epidemiology (GJ), Henry Ford Hospital, Wayne State University, Detroit, Michigan
| | - Manisha Loomba
- Department of Anesthesiology, Henry Ford Hospital, Wayne State University Detroit, Michigan
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Semler MW, Marney AM, Rice TW, Nian H, Yu C, Wheeler AP, Brown NJ. B-Type Natriuretic Peptide, Aldosterone, and Fluid Management in ARDS. Chest 2016; 150:102-11. [PMID: 27018313 DOI: 10.1016/j.chest.2016.03.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/02/2016] [Accepted: 03/07/2016] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Conservative fluid management increases ventilator-free days without influencing overall mortality in acute respiratory distress syndrome. Plasma concentrations of B-type natriuretic peptide (a marker of ventricular filling) or aldosterone (a marker of effective circulating volume) may identify patients for whom fluid management impacts survival. METHODS This was a retrospective analysis of the Fluid and Catheter Treatment Trial (FACTT), a randomized trial comparing conservative with liberal fluid management in acute respiratory distress syndrome. Using plasma collected at study enrollment, we measured B-type natriuretic peptide and aldosterone by immunoassay. Multivariable analyses examined the interaction between B-type natriuretic peptide or aldosterone concentration and fluid strategy with regard to 60-day in-hospital mortality. RESULTS Among 625 patients with adequate plasma, median B-type natriuretic peptide concentration was 825 pg/mL (interquartile range, 144-1,574 pg/mL), and median aldosterone was 2.49 ng/dL (interquartile range, 1.1-4.3 ng/dL). B-type natriuretic peptide did not predict overall mortality, correlate with fluid balance, or modify the effect of conservative vs liberal fluid management on outcomes. In contrast, among patients with lower aldosterone concentrations, conservative fluid management increased ventilator-free days (17.1 ± 9.8 vs 12.5 ± 10.3, P < .001) and decreased mortality (19% vs 30%, P = .03) (P value for interaction = .01). CONCLUSIONS In acute respiratory distress syndrome, B-type natriuretic peptide does not modify the effect of fluid management on outcomes. Lower initial aldosterone appears to identify patients for whom conservative fluid management may improve mortality.
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Affiliation(s)
- Matthew W Semler
- Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN.
| | | | - Todd W Rice
- Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Hui Nian
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Chang Yu
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Arthur P Wheeler
- Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Nancy J Brown
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
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Brain Natriuretic Peptide Levels and the Occurrence of Subclinical Pulmonary Edema in Healthy Lowlanders at High Altitude. Can J Cardiol 2015; 31:1025-31. [DOI: 10.1016/j.cjca.2015.03.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 03/20/2015] [Accepted: 03/20/2015] [Indexed: 11/19/2022] Open
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Gao M, Wang R, Jiayong Z, Liu Y, Sun G. NT-ProBNP levels are moderately increased in acute high-altitude pulmonary edema. Exp Ther Med 2013; 5:1434-1438. [PMID: 23737894 PMCID: PMC3671802 DOI: 10.3892/etm.2013.976] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Accepted: 01/16/2013] [Indexed: 11/18/2022] Open
Abstract
The aim of the present study was to investigate the effect of B-type natriuretic peptides (BNPs) in acute high-altitude pulmonary edema (HAPE). The study enrolled 46 subjects from lowland Han, including 33 individuals who had acutely ascended to a high altitude (21 individuals with HAPE as the case group and 12 individuals without HAPE as the high-altitude control group) and 13 healthy normal residents as the plain control group. The serum concentrations of N-terminal probrain natriuretic peptide (NT-proBNP), erythropoietin (EPO), vascular endothelial growth factor (VEGF) and nitric oxide (NO) were measured. There were significant differences in the serum concentrations of NT-ProBNP, NO, VEGF and EPO among the three groups. The serum concentrations of NT-ProBNP, EPO and VEGF were significantly higher in the HAPE patients and high-altitude control individuals than those of the plain group. No significant differences were identified between the HAPE patients and the high-altitude control group. In contrast to these three parameters, the serum concentrations of NO in the high-altitude control group were significantly higher than those of the HAPE patients and the plain group, while there were no significant differences in the serum concentrations of NO between the HAPE patients and the plain group. Furthermore, serum concentrations of NT-ProBNP and EPO were significantly reduced following treatment in the HAPE patients, however, no significant changes were identified in VEGF or NO concentrations. BNPs are increased in HAPE with severe hypoxia and right ventricular overload, but are decreased subsequent to treatment. BNPs may therefore be a potential biomarker for the diagnosis and prognosis of HAPE.
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Affiliation(s)
- Mingdong Gao
- Department of Cardiology, Tianjin Chest Hospital, Tianjin 30051
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8
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Integrating Optimal Use of Echocardiography and Biomarkers in Heart Disease. CURRENT CARDIOVASCULAR IMAGING REPORTS 2012. [DOI: 10.1007/s12410-012-9167-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Woods DR, Begley J, Stacey M, Smith C, Boos CJ, Hooper T, Hawkins A, Hodkinson P, Green N, Mellor A. Severe acute mountain sickness, brain natriuretic peptide and NT-proBNP in humans. Acta Physiol (Oxf) 2012; 205:349-55. [PMID: 22222437 DOI: 10.1111/j.1748-1716.2012.02407.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 10/10/2011] [Accepted: 12/26/2011] [Indexed: 12/01/2022]
Abstract
AIM To examine the response of brain natriuretic peptide (BNP) and NT-proBNP to high altitude (HA) both at rest and following exercise. METHODS We measured NT-proBNP and BNP and Lake Louise (LL) acute mountain sickness (AMS) scores in 20 subjects at rest in Kathmandu (Kat; 1300 m), following exercise and at rest at 4270 and 5150 m. RESULTS BNP and NT-proBNP (pg ml(-1) , mean ± SEM) rose significantly from Kat (9.2 ± 2 and 36.9 ± 6.6, respectively) to arrival at 4270 m after exercise (16.6 ± 4 and 152 ± 56.1, P=0.008 and P<0.001, respectively) and remained elevated the next morning at rest (28.9 ± 9 and 207.4 ± 65.1, P = 0.004 and P<0.001 respectively). At 5150, immediately following ascent/descent to 5643 m, BNP and NT-proBNP were 32.3 ± 8.8 and 301.1 ± 96.3 (P=0.003 and P<0.001 vs. Kat, respectively) and at rest the following morning were 33.3 ± 9.7 and 258.9 ± 89.5 (P=0.008 and P=0.001 vs. Kat respectively). NT-proBNP and BNP correlated strongly at 5150 m (ρ 0.905, P<0.001 and ρ 0.914, P<0.001 for resting and post-exercise samples respectively). At 5150 m, BNP levels were significantly higher among the four subjects with severe (LL score>6) AMS (58.4 ± 18.7) compared with those without (BNP 22.7 ± 8.6, P=0.048). There were significant correlations between change in body water from baseline to 5150 m with both BNP and NT-proBNP (ρ 0.77, P=0.001, ρ 0.745, P=0.002 respectively). CONCLUSION In conclusion, these data suggest that BNP and NT-proBNP increase with ascent to HA both after exercise and at rest. We also report the novel finding that BNP is significantly greater in those with severe AMS at 5150 m.
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Affiliation(s)
| | - J. Begley
- Department of Biochemistry; Poole Hospital NHS Foundation Trust; Poole; UK
| | | | | | | | | | - A. Hawkins
- Department of Biochemistry; Poole Hospital NHS Foundation Trust; Poole; UK
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Anwar A, Li M, Frid MG, Kumar B, Gerasimovskaya EV, Riddle SR, McKeon BA, Thukaram R, Meyrick BO, Fini MA, Stenmark KR. Osteopontin is an endogenous modulator of the constitutively activated phenotype of pulmonary adventitial fibroblasts in hypoxic pulmonary hypertension. Am J Physiol Lung Cell Mol Physiol 2012; 303:L1-L11. [PMID: 22582113 DOI: 10.1152/ajplung.00050.2012] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Increased cell proliferation and migration, of several cell types are key components of vascular remodeling observed in pulmonary hypertension (PH). Our previous data demonstrate that adventitial fibroblasts isolated from pulmonary arteries of chronically hypoxic hypertensive calves (termed PH-Fibs) exhibit a "constitutively activated" phenotype characterized by high proliferative and migratory potential. Osteopontin (OPN) has been shown to promote several cellular activities including growth and migration in cancer cells. We thus tested the hypothesis that elevated OPN expression confers the "activated" highly proproliferative and promigratory/invasive phenotype of PH-Fibs. Our results demonstrate that, both in vivo and ex vivo, PH-Fibs exhibited increased expression of OPN, as well as its cognate receptors, α(V)β(3) and CD44, compared with control fibroblasts (CO-Fibs). Augmented OPN expression in PH-Fibs corresponded to their high proliferative, migratory, and invasive properties and constitutive activation of ERK1/2 and AKT signaling. OPN silencing via small interfering RNA or sequestering OPN production by specific antibodies led to decreased proliferation, migration, invasion, and attenuated ERK1/2, AKT phosphorylation in PH-Fibs. Furthermore, increasing OPN levels in CO-Fibs via recombinant OPN resulted in significant increases in their proliferative, migratory, and invasive capabilities to the levels resembling those of PH-Fibs. Thus our data suggest OPN as an essential contributor to the activated (highly proliferative, migratory, and proinvasive) phenotype of pulmonary adventitial fibroblasts in hypoxic PH.
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Affiliation(s)
- Adil Anwar
- Department of Pediatrics, University of Colorado Denver, Aurora, CO 80045, USA
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Kellihan HB, Mackie BA, Stepien RL. NT-proBNP, NT-proANP and cTnI concentrations in dogs with pre-capillary pulmonary hypertension. J Vet Cardiol 2011; 13:171-82. [PMID: 21835711 DOI: 10.1016/j.jvc.2011.04.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 04/12/2011] [Accepted: 04/21/2011] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To compare [NT-proBNP], [NT-proANP] and [cTnI] between control dogs with respiratory disease without pulmonary hypertension (PH) and dogs with pre-capillary PH, and to assess the accuracy of [NT-proBNP], [NT-proANP], [cTnI] to predict Doppler-derived peak tricuspid regurgitation (TR) gradient. ANIMALS 20 dogs. 8 control dogs with respiratory disease with no PH and 12 with pre-capillary PH. METHODS [NT-proBNP], [NT-proANP] and [cTnI] were compared between the 2 groups and simple linear regression analysis was used to predict peak TR gradients from various blood biomarkers. RESULTS Median [NT-proBNP] was higher in the dogs with PH (2011 pmol/L, 274-7713 pmol/L) compared to control dogs (744 pmol/L; 531-2710 pmol/L) (p = 0.0339). [NT-proBNP] was associated with peak TR gradient (R(2) = 0.7851, p = 0.0001). Median [NT-proANP] did not differ between dogs with PH (1747 fmol/L; 894-2884 fmol/L) and control dogs (1209 fmol/L; 976-1389 fmol/L (p = 0.058). [NT-proANP] was not associated with peak TR gradient (R(2) = 0.2780, p = 0.0781). Median [cTnI] did not differ between dogs with PH (0.2850 ng/mL; 0.19-1.13 ng/mL) and control dogs (0.2 ng/mL; 0.19-0.82 ng/mL, p = 0.3051). Median [TnI] was not associated with peak TR gradient (R(2) = 0.024, p = 0.6307). CONCLUSIONS [NT-proBNP] concentration is significantly higher in dogs with pre-capillary PH when compared to dogs with respiratory disease without PH, and [NT-proBNP] may be useful to predict the severity of estimated PH. Elevations in [NT-proBNP] due to pre-capillary PH may complicate the interpretation of [NT-proBNP] elevations in patients presenting with cardiorespiratory abnormalities. [NT-proANP] and [cTnI] were not elevated in dogs with pre-capillary PH.
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Affiliation(s)
- Heidi B Kellihan
- Section of Cardiology, Department of Medicine, School of Veterinary Medicine, University of Wisconsin, Madison, USA.
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12
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Cepkova M, Kapur V, Ren X, Quinn T, Zhuo H, Foster E, Matthay MA, Liu KD. Clinical significance of elevated B-type natriuretic peptide in patients with acute lung injury with or without right ventricular dilatation: an observational cohort study. Ann Intensive Care 2011; 1:18. [PMID: 21906356 PMCID: PMC3224453 DOI: 10.1186/2110-5820-1-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 06/13/2011] [Indexed: 11/15/2022] Open
Abstract
Background The primary objective of this study was to examine levels of B-type natriuretic peptide (BNP) in mechanically ventilated patients with acute lung injury and to test whether the level of BNP would be higher in patients with right ventricular dilatation and would predict mortality. Methods This was a prospective, observational cohort study of 42 patients conducted in the intensive care unit of a tertiary care university hospital. BNP was measured and transthoracic echocardiography was performed within 48 hours of the onset of acute lung injury. The left ventricular systolic and diastolic function, right ventricular systolic function, and cardiac output were assessed. BNP was compared in patients with and without right ventricular dilatation, as well as in survivors versus nonsurvivors. Results BNP was elevated in mechanically ventilated patients with acute lung injury (median 420 pg/ml; 25-75% interquartile range 156-728 pg/ml). There was no difference between patients with and without right ventricular dilatation (420 pg/ml, 119-858 pg/ml vs. 387 pg/ml, 156-725 pg/ml; p = 0.96). There was no difference in BNP levels between the patients who died and those who survived at 30 days (420 pg/ml, 120-728 pg/ml vs. 385 pg/ml, 159-1070 pg/ml; p = 0.71). Conclusions In patients with acute lung injury the level of BNP is increased, but there is no difference in the BNP level between patients with and without right ventricular dilatation. Furthermore, BNP level is not predictive of mortality in this population.
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Affiliation(s)
- Magda Cepkova
- Cardiovascular Research Institute, University of California, San Francisco, CA, 94143, USA.
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13
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Woods D, Hooper T, Mellor A, Hodkinson P, Wakeford R, Peaston B, Ball S, Green N. Brain natriuretic peptide and acute hypobaric hypoxia in humans. J Physiol Sci 2011; 61:217-20. [PMID: 21431981 PMCID: PMC10717752 DOI: 10.1007/s12576-011-0141-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 03/03/2011] [Indexed: 11/25/2022]
Abstract
In animal models, the secretion of the cardiac hormone, brain natriuretic peptide (BNP), and its closely related peptide, atrial natriuretic peptide (ANP), are stimulated by acute hypoxia. There is extensive human evidence for a rise in ANP under acute hypoxic conditions but very little evidence regarding the BNP response to acute hypoxia in humans. We therefore subjected seven healthy subjects to an acute hypobaric hypoxic stimulus to examine if BNP secretion increases rapidly. Significant hypoxaemia (mean nadir oxygen saturation 62.3%) was induced but no significant rise in BNP occurred. This suggests that either such acute hypoxaemia is well tolerated by the healthy human heart or it is not a stimulus for BNP secretion.
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Affiliation(s)
- David Woods
- Newcastle and Northumbria NHS Trust, Tyne and Wear, UK.
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14
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Effects of altitude exposure on brain natriuretic peptide in humans. Eur J Appl Physiol 2011; 111:2687-93. [DOI: 10.1007/s00421-011-1881-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 02/16/2011] [Indexed: 10/18/2022]
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Ohata Y, Ogata S, Nakanishi K, Kanazawa F, Uenoyama M, Hiroi S, Tominaga S, Kawai T. Expression of P2X4R mRNA and protein in rats with hypobaric hypoxia-induced pulmonary hypertension. Circ J 2011; 75:945-54. [PMID: 21378451 DOI: 10.1253/circj.cj-09-0575] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The experimental pulmonary hypertension that develops in hypobaric hypoxia is characterized by structural remodeling of the heart. The P2X4 receptor (P2X4R) controls vascular tone and vessel remodeling in several blood vessels, and it has emerged as a key factor in the enhancement of cardiovascular performance. METHODS AND RESULTS To study the possible effects of hypobaric hypoxia on the P2X4R-synthesis system, 150 male Wistar rats were housed in a chamber at the equivalent of the 5,500 m altitude level for 21 days. After 14 days' exposure to hypobaric hypoxia, pulmonary arterial pressure (PAP) was significantly increased. In the right ventricle (RV) of the heart, P2X4R expression was significantly increased on days 1 and 14 (mRNA) and on days 7 and 21 (protein) of hypobaric hypoxic exposure. Immunohistochemical staining for P2X4R protein became more intense in RV in the late phase of exposure. These changes in P2X4R synthesis in RV occurred alongside the increase in PAP. In addition, P2X1R and P2Y2R mRNA levels in the RV were significantly increased on days 1, 14, and 21, and day 5, respectively, of exposure. The level of P2X1R protein in the RV was significantly increased on day 21 of exposure. CONCLUSIONS Conceivably, P2 receptors, including P2X4R and P2X1R, might play roles in modulating the RV hypertrophy that occurs due to pulmonary hypertension in hypobaric hypoxia.
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Affiliation(s)
- Yuichiro Ohata
- Department of Pathology and Laboratory Medicine, National Defense Medical College, Tokorozawa, Japan
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Woods D, Stacey M, Hill N, Alwis ND. Endocrine Aspects of High Altitude Acclimatization and Acute Mountain Sickness. J ROY ARMY MED CORPS 2011; 157:33-7. [DOI: 10.1136/jramc-157-01-06] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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17
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Uenoyama M, Ogata S, Nakanishi K, Kanazawa F, Hiroi S, Tominaga S, Seo A, Matsui T, Kawai T, Suzuki S. Protein kinase C mRNA and protein expressions in hypobaric hypoxia-induced cardiac hypertrophy in rats. Acta Physiol (Oxf) 2010; 198:431-40. [PMID: 19995357 DOI: 10.1111/j.1748-1716.2009.02064.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM Protein kinase C (PKC), cloned as a serine/threonine kinase, plays key roles in diverse intracellular signalling processes and in cardiovascular remodelling during pressure overload or volume overload. We looked for correlations between changes in PKC isoforms (levels and/or subcellular distributions) and cardiac remodelling during experimental hypobaric hypoxic environment (HHE)-induced pulmonary hypertension. METHODS To study the PKC system in the heart during HHE, 148 male Wistar rats were housed for up to 21 days in a chamber at the equivalent of 5500 m altitude level (10% O(2)). RESULTS At 14 or more days of exposure to HHE, pulmonary arterial pressure (PAP) was significantly increased. In the right ventricle (RV): (1) the expression of PKC-alpha protein in the cytosolic and membrane fractions was increased at 3-14 days and at 5-7 days of exposure respectively; (ii) the cytosolic expression of PKC-delta protein was increased at 1-5, 14 and 21 days of exposure; (3) the membrane expressions of the proteins were decreased at 14-21 (PKC-betaII), 14-21 (PKC-gamma), and 0.5-5 and 21 (PKC-epsilon) days of exposure; (4) the expression of the active form of PKC-alpha protein on the plasma membrane was increased at 3 days of exposure (based on semiquantitative analysis of the immunohistochemistry). In the left ventricle, the expressions of the PKC mRNAs, and of their cytosolic and membrane proteins, were almost unchanged. The above changes in PKC-alpha, which were strongly evident in the RV, occurred alongside the increase in PAP. CONCLUSION PKC-alpha may help to modulate the right ventricular hypertrophy caused by pulmonary hypertension in HHE.
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Affiliation(s)
- M Uenoyama
- National Defense Medical College Research Institute, Tokorozawa, Japan
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18
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Natriuretic Peptides in Systemic Sclerosis-related Pulmonary Arterial Hypertension. Semin Arthritis Rheum 2010; 39:278-84. [DOI: 10.1016/j.semarthrit.2009.03.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2009] [Revised: 03/10/2009] [Accepted: 03/30/2009] [Indexed: 11/18/2022]
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Abstract
PURPOSE OF REVIEW Natriuretic peptides are markers of heart failure and/or cardiac dysfunction that provide useful diagnostic and prognostic information in patients with dyspnea and/or respiratory failure in the emergency department. Cardiac troponins (cTn) have markedly simplified the diagnosis of myocardial infarction. In critically ill patients, conditions like coexisting organ dysfunction multiorgan involvement or altered synthesis/clearance may confound interpretation of designated biomarkers, including natriuretic peptides and cTn. This review focuses on recently published articles relating to the use of natriuretic peptides and cTn in critically ill patients. RECENT FINDINGS One new study addresses diagnostic utility of B-type natriuretic peptide to distinguish low-pressure pulmonary edema (acute lung injury/acute respiratory distress syndrome) from high-pressure (cardiogenic) pulmonary edema. Other studies highlight the prognostic value of natriuretic peptides either in unselected and general noncardiac ICU patients and reveal an important reason for elevated B-type natriuretic peptide levels in septic shock.Interesting data focusing on diagnostic and prognostic ability of systematic cTn screening measurements in ICU patients became available. SUMMARY Recent studies confirm the excellent prognostic value of natriuretic peptide measurements in ICU patients. Diagnostic properties of natriuretic peptide in ICU patients still remain ambiguous and require further evaluation. Systematic screening with cTn reveals more myocardial infarctions and provides important prognostic information.
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Affiliation(s)
- Markus Noveanu
- Department of Internal Medicine, University Hospital Basel, Basel, Switzerland.
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Yu J, Feng HS, Chen BY, Qu P, Liu LB, Chen JK, Tie R, Huang XJ, Zhao YF, Zhu XX, Zhu MZ. Protective effects of vasonatrin peptide against hypobaric hypoxia-induced pulmonary hypertension in rats. Clin Exp Pharmacol Physiol 2009; 37:69-74. [PMID: 19566831 DOI: 10.1111/j.1440-1681.2009.05240.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. The aim of the present study was to investigate the in vivo effects of vasonatrin peptide (VNP) on hypoxia-induced pulmonary hypertension (HPH). 2. The HPH model was developed by subjecting rats to hypobaric hypoxia. The HPH rats were then treated with either VNP (50 microg/kg per day, i.p.) or saline (0.5 mL, i.p.) every day for 7 days. Haemodynamic indices, right ventricular hypertrophy (RVH) and remodelling of the pulmonary arteries were evaluated. In addition, plasma levels of atrial natriuretic peptide (ANP), endothelin (ET)-1 and angiotensin II (AngII) were determined, as was natriuretic peptide receptor-C (NPR-C) mRNA expression in the right ventricle. 3. Hypobaric hypoxia induced severe HPH compared with the normoxic control group. Treatment of HPH rats with VNP for 1 week significantly reduced mean pulmonary arterial pressure, pulmonary vascular resistance, RVH and muscularization of the pulmonary arteries, although pulmonary blood flow was increased in this group. In addition, significantly lower levels of plasma ET-1 and AngII and cardiac NPR-C mRNA expression were observed in VNP-treated compared with saline-treated HPH rats, whereas higher plasma concentrations of ANP were found in the former group. Acute intravenous administration of 50 microg/kg VNP significantly ameliorated pulmonary haemodynamics in HPH rats. 4. Taken together, the date indicate that VNP has certain preventative and therapeutic effects against HPH.
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Affiliation(s)
- Jun Yu
- Center of Teaching Experiment, School of Basic Medical Science, Xi'an
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21
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Abstract
PURPOSE OF REVIEW B-type natriuretic peptides are quantitative markers of heart failure (and/or cardiac stress) that summarize the extent of systolic and diastolic left ventricular dysfunction, valvular dysfunction, and right ventricular dysfunction. Based on the observation that heart failure is common albeit difficult to diagnose in the ICU, several studies have begun to evaluate the potential use of B-type natriuretic peptides in various ICU settings. RECENT FINDINGS Previous pilot studies have examined the use of B-type natriuretic peptide in the differential diagnosis of hypoxemic respiratory failure, to differentiate cardiogenic from noncardiogenic shocks or to predict fluid responsiveness, to assess myocardial dysfunction and prognosis in patients with severe sepsis, and to predict ventilatory weaning failure. SUMMARY Although previous studies were small, they highlight the potential of using B-type natriuretic peptides as a noninvasive easily available tool to quantify cardiac stress.
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Toshner MR, Thompson AAR, Irving JB, Baillie JK, Morton JJ, Peacock AJ. NT-proBNP Does Not Rise on Acute Ascent to High Altitude. High Alt Med Biol 2008; 9:307-10. [DOI: 10.1089/ham.2008.1054] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Troisi F, Greco S, Brunetti ND, Di Biase M. Right heart dysfunction assessed with echography, B-type natriuretic peptide and cardiopulmonary test in patients with chronic heart failure. J Cardiovasc Med (Hagerstown) 2008; 9:672-6. [PMID: 18545065 DOI: 10.2459/jcm.0b013e3282f331eb] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Right ventricle (RV) impairment could influence brain natriuretic peptide (BNP) circulating levels. It is not well known whether echocardiographic parameters assessing RV function could be related to BNP levels in patients with chronic heart failure (CHF). Controversial data are available about the role played by RV dysfunction in determining exercise capacity in CHF patients. METHODS Sixty patients with CHF referred to our CHF Unit underwent blood sampling for BNP levels determination, cardiopulmonary exercise test with VO2 peak, VO2-AT and VE/VCO2 slope assessment and M-mode, two-dimensional and Doppler echocardiography with evaluation of right heart function [right atrial pressure (RAP), pulmonary artery pressure (PAP), severity of tricuspid regurgitation (TR), and tricuspid annular plane systolic excursion (TAPSE)]. RESULTS A significant correlation was detectable between BNP levels and TAPSE (r = -0.33; P < 0.05), RAP (r = 0.34; P < 0.05), PAP (r = 0.42; P < 0.05), TR (P for trend 0.05); correlation with TAPSE remained significant even in multivariate. VO2 peak was significantly related to RAP (r = -0.38, P < 0.05) and TR (P for trend 0.05); AT with PAP (r = -0.40, P < 0.05), RAP (r = -0.50, P < 0.05), TR (P for trend 0.05). Moreover, patients with TAPSE greater than 16 mm had higher values of VO2 peak (13.68 +/- 3.28 vs. 11.49 +/- 2.37 ml/kg/m', P < 0.05) and of VO2-AT (18.36 +/- 1.60 vs. 10.23 +/- 2.31 ml/kg/m'; P < 0.05). CONCLUSION Right heart dysfunction assessed by simple echocardiographic parameters is related to neurohormonal activation featured by increased BNP levels and to a worse functional capacity in CHF patients.
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Uenoyama M, Ogata S, Nakanishi K, Kanazawa F, Hiroi S, Tominaga S, Kanatani Y, Seo A, Matsui T, Suzuki S. Osteopontin expression in normal and hypobaric hypoxia-exposed rats. Acta Physiol (Oxf) 2008; 193:291-301. [PMID: 18284657 DOI: 10.1111/j.1748-1716.2008.01844.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM Experimental pulmonary hypertension induced in a hypobaric hypoxic environment (HHE) is characterized by structural remodelling of the heart and pulmonary arteries. Osteopontin (OPN) has emerged as a key factor in cardiovascular remodelling in response to pressure or volume overload. We studied the possible effects of HHE on the OPN synthesis system. METHODS One hundred and forty-eight male Wistar rats were housed in a chamber with conditions equivalent of an altitude of 5500 m for up to 21 days. RESULTS Plasma OPN protein level was found to be significantly decreased on day 0.5 of exposure to HHE, as was the level in the adrenal gland (which secreted highest levels of OPN protein). In the right ventricle of the heart (mRNA) and the lung (protein), OPN expression was found to be significantly increased only on day 1 and day 5, respectively, of exposure to HHE. By immunohistochemistry, the distribution and intensity of OPN protein in several organs were found to alter during exposure to HHE. However, these changes in OPN synthesis did not coincide with the moderate increase in pulmonary arterial pressure (PAP) (maximal mean PAP, 24.5 mmHg) during HHE. CONCLUSION Pulmonary hypertension in HHE with conditions equivalent of an altitude of 5500 m may induce little or no OPN in heart and lung. Sustained induction may require a more severe PAP overload.
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Affiliation(s)
- M Uenoyama
- Division of Environmental Medicine, National Defense Medical College Research Institute, Tokorozawa, Japan
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Mair J, Hammerer-Lercher A, Mittermayr M, Klingler A, Humpeler E, Pachinger O, Schobersberger W. 3-week hiking holidays at moderate altitude do not impair cardiac function in individuals with metabolic syndrome. Int J Cardiol 2007; 123:186-8. [PMID: 17316842 DOI: 10.1016/j.ijcard.2006.11.127] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Accepted: 11/12/2006] [Indexed: 10/23/2022]
Abstract
We studied the influence of a 3-week hiking vacation at moderate altitude on cardiac pump and endocrine function. 18 males (mean age: 55 years, range 36-60) with metabolic syndrome participated in a 3-week structured guided hiking vacation program (4 times per week at 55-65% of maximal heart rate, total exercise time 29 h). Echocardiography, B-type natriuretic peptide (BNP), NT-proBNP, and endothelin-1 measurements were performed at baseline in Innsbruck (576 m a.s.l., Austria), on the first day at moderate altitude (Obertauern, 1700 m a.s.l., Austria), after 3 weeks in Obertauern, and at follow-up in Innsbruck. We found no adverse cardiovascular effects and no significant changes in echocardiographic measures of systolic or diastolic function, estimated systolic pulmonary artery pressure, exercise capacities, BNP and NT-proBNP, or endothelin-1 concentrations. The blood pressure at rest significantly decreased from baseline to follow-up.
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Kanazawa F, Nakanishi K, Osada H, Kanamaru Y, Ohrui N, Uenoyama M, Masaki Y, Kanatani Y, Hiroi S, Tominaga S, Yakata-Suzuki A, Matsuyama S, Kawai T. Expression of endothelin-1 in the brain and lung of rats exposed to permanent hypobaric hypoxia. Brain Res 2005; 1036:145-54. [PMID: 15725412 DOI: 10.1016/j.brainres.2004.12.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2004] [Revised: 10/21/2004] [Accepted: 12/15/2004] [Indexed: 12/21/2022]
Abstract
High-altitude hypoxia causes pulmonary hypertension in humans and animals. Endothelin-1 (ET-1) is a novel and long-lasting vasoconstrictor. However, no study has dealt with the effects of a hypobaric hypoxic environment (HHE) on ET-1 activity in the brain. We examined 134 male rats permanently exposed to the equivalent of 5500 m altitude for 1 to 8 weeks. In these HHE rats, the mean pulmonary arterial pressure was significantly raised. The level of ET-1 protein, measured by enzyme immunoassay, increased rapidly in the lungs on exposure to HHE, but decreased in the brain. The level of ET-1 mRNA, measured by semiquantitative RT-PCR, was raised at 1, 4, and 6 weeks' exposure in the lungs and at 4 or more weeks' exposure in 3 of 8 brain regions. By in situ hybridization and immunohistochemistry of brain sections, ET-1 mRNA and protein were detected in the endothelial cells, neurons, and astrocyte-like cells in control rats. In HHE rats, the immunoreactive intensity for ET-1 protein decreased rapidly with time in these cells within the brain, although a few weakly ET-1 protein-positive cells were detected until 8 weeks' exposure to HHE. Only a few weakly ET-1 mRNA-positive endothelial cells were detected in any HHE rats. Although the reactivity for ET-1 mRNA had decreased significantly in neurons and astrocyte-like cells at 1 and 2 weeks' exposure to HHE, it was again strong in both types of cells at 4 weeks' exposure to HHE. These results raise the possibility that during exposure to HHE, ET-1 production in the lung may play a role in the development of pulmonary hypertension, while a decrease in ET-1 production within the brain may help to protect neurons by preventing or limiting the constriction of cerebral microvessels during the hypoxia induced by HHE.
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Affiliation(s)
- Fumiko Kanazawa
- Biochemical Section, 2nd Division, Aeromedical Laboratory, Japan Air Self-Defense Force, Tachikawa 190-0003, Japan
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Abstract
A growing number of mammalian genes whose expression is inducible by hypoxia have been identified. Among them, atrial natriuretic peptide (ANP) synthesis and secretion is increased during hypoxic exposure and plays an important role in the normal adaptation to hypoxia and in the pathogenesis of cardiopulmonary diseases, including chronic hypoxia-induced pulmonary hypertension and vascular remodeling, and right ventricular hypertrophy and right heart failure. This review discusses the roles of ANP and its receptors in hypoxia-induced pulmonary hypertension. We and other investigators have demonstrated that ANP gene expression is enhanced by exposure to hypoxia and that the ANP so generated protects against the development of hypoxic pulmonary hypertension. Results also show that hypoxia directly stimulates ANP gene expression and ANP release in cardiac myocytes in vitro. Several cis-responsive elements of the ANP promoter are involved in the response to changes in oxygen tension. Further, the ANP clearance receptor NPR-C, but not the biological active NPR-A and NPR-B receptors, is downregulated in hypoxia adapted lung. Hypoxia-sensitive tyrosine kinase receptor-associated growth factors, including fibroblast growth factor (FGF) and platelet derived growth factor (PDGF)-BB, but not hypoxia per se, inhibit NPR-C gene expression in pulmonary arterial smooth muscle cells in vitro. The reductions in NPR-C in the hypoxic lung retard the clearance of ANP and allow more ANP to bind to biological active NPR-A and NPR-B in the pulmonary circulation, relaxing preconstricted pulmonary vessels, reducing pulmonary arterial pressure, and attenuating the development of hypoxia-induced pulmonary hypertension and vascular remodeling.
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Affiliation(s)
- Yiu-Fai Chen
- Vascular Biology and Hypertension Program, Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Yap LB, Mukerjee D, Timms PM, Ashrafian H, Coghlan JG. Natriuretic Peptides, Respiratory Disease, and the Right Heart. Chest 2004; 126:1330-6. [PMID: 15486400 DOI: 10.1378/chest.126.4.1330] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
It is well-recognized that atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) are raised in conditions with ventricular volume and pressure overload. In addition to this established role in left ventricular congestive cardiac failure, there is good evidence that BNP has a diagnostic role in right ventricular (RV) dysfunction and pulmonary arterial hypertension (PAH). For example, BNP levels can be used to differentiate between dyspneic patients with pure respiratory defects and those with RV dysfunction. Studies in patients with PAH have demonstrated significant correlations between BNP levels and mean pulmonary arterial pressure as well as pulmonary vascular resistance. Additionally, BNP has a prognostic role in patients with RV pressure overload and pulmonary hypertension, and it offers a noninvasive test that can be used to guide therapy in patients with PAH. However, although measured plasma proBNP levels are raised in conditions with RV overload, its biological significance is still not well-understood. In this article, we review the general physiologic and potential therapeutic role of natriuretic peptides in respiratory disease, RV dysfunction, and PAH. Furthermore, we assess the various clues toward natriuretic peptide action coming from laboratory studies. ANP and BNP knockout mice develop cardiac fibrosis and hypertrophy. Potentiation of the natriuretic pathway has been shown to reduce cardiac hypertrophy and PAH. This is likely to take place as a result of increased intracellular cyclic guanosine monophosphate levels and subsequent pulmonary vasorelaxant activity. In view of this evidence, there may be a rationale for the therapeutic use of recombinant BNP or neutral endopeptidase inhibitors under conditions of RV dysfunction and PAH.
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Affiliation(s)
- Lok Bin Yap
- Department of Cardiology, Homerton University Hospital, Homerton Row, London E9 6SR, UK.
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Yap LB, Ashrafian H, Mukerjee D, Coghlan JG, Timms PM. The natriuretic peptides and their role in disorders of right heart dysfunction and pulmonary hypertension. Clin Biochem 2004; 37:847-56. [PMID: 15369714 DOI: 10.1016/j.clinbiochem.2004.06.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2003] [Accepted: 06/01/2004] [Indexed: 11/23/2022]
Abstract
Atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) are increased in conditions with cardiac ventricular volume and pressure overload. The general physiological and potential therapeutic roles of natriuretic peptides in respiratory disease, right ventricular (RV) dysfunction, and pulmonary arterial hypertension (PAH) are reviewed. BNP levels can be used to differentiate between dyspneic patients with a pure respiratory defect and those with RV dysfunction. BNP levels also correlate with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) in patients with PAH (atrial septal defect, chronic thromboembolic disease, and scleroderma). BNP is a predictor of mortality in patients with primary pulmonary hypertension (PPH). These are important clinical implications in that a noninvasive blood test may be used to identify high-risk patients for more invasive procedures such as cardiac catheterization. BNP or NT-proBNP measurements may also be used to guide therapy (e.g., pulmonary vasorelaxants) in PAH since upregulation of the natriuretic peptide pathway has been shown to reduce cardiac hypertrophy and PAH. Additionally, there may be therapeutic potential via recombinant BNP or neutral endopeptidase inhibitors in RV dysfunction and PAH.
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Affiliation(s)
- Lok B Yap
- Department of Cardiology, Homerton University Hospital NHS Trust, London, E9 6SR, UK.
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Nakanishi K, Osada H, Uenoyama M, Kanazawa F, Ohrui N, Masaki Y, Hayashi T, Kanatani Y, Ikeda T, Kawai T. Expressions of adrenomedullin mRNA and protein in rats with hypobaric hypoxia-induced pulmonary hypertension. Am J Physiol Heart Circ Physiol 2004; 286:H2159-68. [PMID: 14715505 DOI: 10.1152/ajpheart.00846.2003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Experimental pulmonary hypertension induced in a hypobaric hypoxic environment (HHE) is characterized by structural remodeling of the heart and pulmonary arteries. Adrenomedullin (AM) has diuretic, natriuretic, and hypotensive effects. To study the possible effects of HHE on the AM synthesis system, 150 male Wistar rats were housed in a chamber at the equivalent of a 5,500-m altitude level for 21 days. After 14 days of exposure to HHE, pulmonary arterial pressure (PAP) was significantly increased (compared with control rats). The plasma AM protein level was significantly increased on day 21 of exposure to HHE. In the right ventricle (RV), right atrium, and left atrium of the heart, the expressions of AM mRNA and protein were increased in the middle to late phase (5–21 days) of HHE, whereas in the brain and lung they were increased much earlier (0.5–5 days). In situ hybridization and immunohistochemistry showed AM mRNA and protein staining to be more intense in the RV in animals in the middle to late phase of HHE exposure than in the controls. During HHE, these changes in AM synthesis, which occurred strongly in the RV, occurred alongside the increase in PAP. Conceivably, AM may play a role in modulating pulmonary hypertension in HHE.
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Affiliation(s)
- Kuniaki Nakanishi
- Department of Pathology, National Defense Medical College, Tokorozawa 359-8513, Japan.
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Mariano-Goulart D, Eberlé MC, Boudousq V, Hejazi-Moughari A, Piot C, Caderas de Kerleau C, Verdier R, Barge ML, Comte F, Bressot N, Rossi M, Kotzki PO. Major increase in brain natriuretic peptide indicates right ventricular systolic dysfunction in patients with heart failure. Eur J Heart Fail 2003; 5:481-8. [PMID: 12921809 DOI: 10.1016/s1388-9842(03)00041-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
This study sought to investigate whether the presence of right ventricular systolic dysfunction with pre-existing left ventricular systolic dysfunction is associated with higher plasma brain natriuretic peptide (BNP) levels, compared with patients with isolated left ventricular dysfunction. Eighty-five patients referred for evaluation of isotopic ventricular function were prospectively included in the study. Left (LVEF) and right (RVEF) ventricular ejection fractions were evaluated by gated blood pool scintigraphy and compared with plasma BNP levels. BNP correlated negatively with LVEF, except in patients with ischaemic heart disease (P=0.09) and in patients with LVEF<40% (P=0.11). In contrast, BNP levels correlated negatively with RVEF for all subgroups. Among patients with RVEF<40%, no significant BNP difference was found between patients with or without additional left ventricular systolic dysfunction (P=0.51). Among patients with LVEF<40%, plasma BNP levels were significantly higher in patients with RVEF<40% than in patients with RVEF>/=40% (P=0.004) whereas age, renal function, clinical findings, ventricular volumes, LVEF or medication were not significantly different. In conclusion, an important increase in BNP levels in patients with left ventricular systolic dysfunction should be considered by cardiologists as an indication of high risk of right ventricular dysfunction and should justify further investigation.
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Affiliation(s)
- Denis Mariano-Goulart
- Department of Nuclear Medicine, Montpellier University Hospital, 371, Avenue du Doyen Gaston Giraud, 34295 Cedex 5, Montpellier, France.
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