Inducible regulation of human brain natriuretic peptide promoter in transgenic mice

2001 ◽  
Vol 280 (1) ◽  
pp. H368-H376 ◽  
Author(s):  
Quan He ◽  
Ding Wang ◽  
Xiao-Ping Yang ◽  
Oscar A. Carretero ◽  
Margot C. LaPointe
Keyword(s):  
Transgenic Mice ◽  
Brain Natriuretic Peptide ◽  
Cardiac Myocytes ◽  
Natriuretic Peptide ◽  
Luciferase Activity ◽  
Left Ventricular ◽  
Neonatal Rat ◽  
Luciferase Reporter ◽  
Coronary Artery Ligation

Studies have shown that brain natriuretic peptide (BNP) gene expression is rapidly induced in the infarcted heart and that plasma BNP levels reflect the degree of left ventricular dysfunction. Our previous in vitro work using transiently transfected neonatal rat cardiac myocytes has shown that the human BNP (hBNP) promoter, in particular a region extending from −127 to −40 relative to the start site of transcription, is more active in cardiac myocytes than in fibroblasts. To study tissue-specific and transcriptional regulation of the hBNP gene in vivo, we generated transgenic mice containing the proximal hBNP promoter (−408 to +100) coupled to a luciferase reporter gene. In four lines of transgenic mice, luciferase activity was ∼33- to 100-fold higher in the heart than in other tissues, including the whole brain. To test whether the transgene responded to a pathophysiological stimulus, we induced infarction by coronary artery ligation. Luciferase activity was fivefold higher in the infarcted region of the left ventricle at 48 h than in sham-operated animals and remained elevated for 4 wk. Endogenous BNP mRNA was similarly increased in the infarcted hearts of a separate group of mice. We conclude that 1) the proximal 408-bp region of the hBNP promoter confers cardiac-specific expression and 2) myocardial infarction activates the proximal hBNP promoter in vivo. These data suggest that we have a valid model for the study of basal and inducible regulation of the hBNP gene in vivo.

Phospholipase A 2 Metabolites Mediate Endothelin Stimulation of the Human Brain Natriuretic Peptide Promoter

Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 721-721
Author(s):  
Quan He
Keyword(s):  
Gene Expression ◽  
Brain Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Promoter Activity ◽  
Luciferase Activity ◽  
Phospholipase A ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
P450 Monooxygenase ◽  
Stimulation Of

P155 Brain natriuretic peptide (BNP) gene expression accompanies cardiac hypertrophy and heart failure. The vasoconstrictor endothelin-1 (ET)may be involved in the development of these diseases. ET has also been shown to activate phospholipase A 2 (PLA 2 ). Thus we studied whether ET and PLA 2 metabolites regulate BNP gene expression. The hBNP promoter (-1818 to + 100) coupled to a luciferase reporter gene was transferred into neonatal ventricular myocytes (NVM),and luciferase activity was measured as an index of promoter activity. ET (10 -7 M)induced BNP mRNA in NVM as assessed by Northern blot. It also stimulated the hBNP promoter 4-fold vs control, an effect completely inhibited by actinomycin D. To test the involvement of different PLA 2 isoforms, transfected cells were treated with the Ca ++ -independent PLA 2 (iPLA 2 )inhibitor bromoenol lactone (BEL), the cytosolic PLA 2 inhibitor methyl arachidonyl fluorophosphonate, or the secretory PLA 2 inhibitor ONO-RS-082 prior to stimulation with ET. Only the iPLA 2 inhibitor BEL prevented ET-stimulated hBNP promoter activity. The PLA 2 metabolite lysophosphatidic acid (LPA) also activated the hBNP promoter (2.2-fold; n = 3), but lysophosphatidylcholine did not. To test whether arachidonic acid metabolites are involved in ET’s effect, cells were pretreated with either a lipoxygenase (LO), cyclooxygenase, or p450 monooxygenase inhibitor. Only the LO inhibitor baicalein prevented ET stimulation of the hBNP promoter. Finally, we studied the involvement of cis elements in ET-stimulated hBNP promoter activity. Deletion of BNP promoter sequences from -1818 to -408 and from -408 to -40 reduced ET’s effect by 54% and 78%, respectively. Moreover, ET-stimulated luciferase activity was reduced by 53% when the GATA element (at position -85 relative to the start site of transcription) was mutated. These data suggest that: 1) ET activates the hBNP promoter through a transcriptional mechanism; 2) LPA, perhaps generated by a BEL-sensitive iPLA 2 , is involved in ET’s effect; 3) a LO pathway may also mediate ET signaling; and 4) ET regulation of the hBNP promoter targets both distal and proximal cis elements, including GATA.

Left ventricular targeting of reporter gene expression in vivo by human BNP promoter in an adenoviral vector

2002 ◽  
Vol 283 (4) ◽  
pp. H1439-H1445 ◽  
Author(s):  
Margot C. LaPointe ◽  
Xiao-Ping Yang ◽  
Oscar A. Carretero ◽  
Quan He
Keyword(s):  
Reporter Gene ◽  
Cardiac Myocyte ◽  
Luciferase Activity ◽  
Recombinant Adenovirus ◽  
Left Ventricular ◽  
Luciferase Reporter ◽  
Mouse Heart ◽  
Free Wall

To selectively introduce genes into the mouse myocardium, we used a recombinant adenovirus encoding a transgene composed of a cardiac-specific promoter [the proximal human brain natriuretic peptide (hBNP) promoter] coupled to a luciferase reporter gene (Ad.hBNPLuc). Activity in vitro and in vivo was compared with Ad.CMVLuc, which contained the cytomegalovirus (CMV) enhancer/promoter. We tested cell-specific and inducible regulation of Ad.hBNPLuc in vitro. Expression was higher in neonatal cardiac myocytes than in a fibroblast cell line and was induced by interleukin-1β, phenylephrine, and isoproterenol in myocytes. For in vivo experiments, Ad.hBNPLuc, Ad.CMVLuc, or vehicle was injected into the left ventricular (LV) free wall of the mouse heart. In Ad.hBNPLuc-injected mice, luciferase activity was only detected in the heart. In contrast, Ad.CMVLuc-injected mice had detectable luciferase activity in all tissues examined. Our studies indicate that 1) the cardiac-specific hBNP promoter and direct cardiac injection limit expression of the transgene to the LV free wall; and 2) transgene expression in vitro is inducible and cardiac myocyte specific. Thus the use of the proximal hBNP promoter in recombinant adenoviral vectors may allow cardiac-specific and inducible expression of therapeutic genes in vivo and prevent some of the side effects of systemic adenovirus administration.

scholarly journals N-Terminal Pro-Brain Natriuretic Peptide and Right Ventricular Diameter Are Related to Aspirin Resistance in Coronary Artery Disease Patients

Medicina ◽  
2021 ◽  
Vol 57 (7) ◽  
pp. 706
Author(s):  
Kamila Marika Cygulska ◽  
Łukasz Figiel ◽  
Dariusz Sławek ◽  
Małgorzata Wraga ◽  
Marek Dąbrowa ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Brain Natriuretic Peptide ◽  
Right Ventricular ◽  
Left Ventricular Mass ◽  
Natriuretic Peptide ◽  
Hemoglobin Concentration ◽  
Left Ventricular ◽  
Ventricular Mass ◽  
Artery Disease

Background and Objectives: Resistance to ASA (ASAres) is a multifactorial phenomenon defined as insufficient reduction of platelet reactivity through incomplete inhibition of thromboxane A2 synthesis. The aim is to reassess the prevalence and predictors of ASAres in a contemporary cohort of coronary artery disease (CAD) patients (pts) on stable therapy with ASA, 75 mg o.d. Materials and Methods: We studied 205 patients with stable CAD treated with daily dose of 75 mg ASA for a minimum of one month. ASAres was defined as ARU (aspirin reaction units) ≥550 using the point-of-care VerifyNow Aspirin test. Results: ASAres was detected in 11.7% of patients. Modest but significant correlations were detected between ARU and concentration of N-terminal pro-brain natriuretic peptide (NT-proBNP) (r = 0.144; p = 0.04), body weight, body mass index, red blood cell distribution width, left ventricular mass, and septal end-systolic thickness, with trends for left ventricular mass index and prothrombin time. In multivariate regression analysis, log(NT-proBNP) was identified as the only independent predictor of ARU—partial r = 0.15, p = 0.03. Median concentrations of NT-proBNP were significantly higher in ASAres patients (median value 311.4 vs. 646.3 pg/mL; p = 0.046) and right ventricular diameter was larger, whereas mean corpuscular hemoglobin concentration was lower as compared to patients with adequate response to ASA. Conclusions: ASAres has significant prevalence in this contemporary CAD cohort and NT-proBNP has been identified as the independent correlate of on-treatment ARU, representing a predictor for ASAres, along with right ventricular enlargement and lower hemoglobin concentration in erythrocytes.

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