1
|
Guerrelli D, Desai M, Semaan Y, Essa Y, Zurakowski D, Cendali F, Reisz J, D'Alessandro A, Luban N, Posnack NG. Prevalence and clinical implications of heightened plastic chemical exposure in pediatric patients undergoing cardiopulmonary bypass. Transfusion 2024; 64:808-823. [PMID: 38590100 DOI: 10.1111/trf.17821] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/30/2024] [Accepted: 03/18/2024] [Indexed: 04/10/2024]
Abstract
BACKGROUND Phthalate chemicals are used to manufacture plastic medical products, including many components of cardiopulmonary bypass (CPB) circuits. We aimed to quantify iatrogenic phthalate exposure in pediatric patients undergoing cardiac surgery and examine the link between phthalate exposure and postoperative outcomes. STUDY DESIGN AND METHODS The study included pediatric patients undergoing (n=122) unique cardiac surgeries at Children's National Hospital. For each patient, a single plasma sample was collected preoperatively and two additional samples were collected postoperatively upon return from the operating room and the morning after surgery. Concentrations of di(2-ethylhexyl) phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry. RESULTS Patients were subdivided into three groups, according to surgical procedure: (1) cardiac surgery not requiring CPB support, (2) cardiac surgery requiring CPB with a crystalloid prime, and (3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with an RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience postoperative complications. RBC washing was an effective strategy to reduce phthalate levels in CPB prime. DISCUSSION Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with an RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.
Collapse
Affiliation(s)
- Devon Guerrelli
- Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA
- Department of Biomedical Engineering, The George Washington University School of Engineering and Applied Science, Washington, DC, USA
| | - Manan Desai
- Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
- Division of Cardiac Surgery, Children's National Hospital, Washington, DC, USA
| | - Youssef Semaan
- Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
- Department of Cardiovascular Services - Perfusion, Children's National Hospital, Washington, DC, USA
| | - Yasin Essa
- Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
- Division of Cardiac Surgery, Children's National Hospital, Washington, DC, USA
| | - David Zurakowski
- Department of Anesthesiology, Critical Care and Pain Medicine, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Francesca Cendali
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Julie Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Naomi Luban
- Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
- Division of Hematology and Laboratory Medicine, Children's National Hospital, Washington, DC, USA
- Department of Pathology, The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Nikki Gillum Posnack
- Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA
- Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
- Department of Pharmacology and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| |
Collapse
|
2
|
Salameh S, Guerrelli D, Miller JA, Desai M, Moise N, Yerebakan C, Bruce A, Sinha P, d'Udekem Y, Weinberg SH, Posnack NG. Connecting Transcriptomics with Computational Modeling to Reveal Developmental Adaptations in the Human Pediatric Myocardium. bioRxiv 2024:2024.04.19.589826. [PMID: 38712262 PMCID: PMC11071413 DOI: 10.1101/2024.04.19.589826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Background Nearly 1% or 1.3 million babies are born with congenital heart disease (CHD) globally each year - many of whom will require palliative or corrective heart surgery within the first few years of life. A detailed understanding of cardiac maturation can help to expand our knowledge on cardiac diseases that develop during gestation, identify age-appropriate cardiovascular drug therapies, and inform clinical care decisions related to surgical repair, myocardial preservation, or postoperative management. Yet, to date, our knowledge of the temporal changes that cardiomyocytes undergo during postnatal development is largely limited to animal models. Methods Right atrial tissue samples were collected from n=117 neonatal, infant, and pediatric patients undergoing correct surgery due to (acyanotic) CHD. Patients were stratified into five age groups: neonate (0-30 days), infant (31-364 days), toddler to preschool (1-5 years), school age (6-11 years), and adolescent to young adults (12-32 years). We measured age-dependent adaptations in cardiac gene expression, and used computational modeling to simulate action potential and calcium transients. Results Enrichment of differentially expressed genes (DEG) was explored, revealing age-dependent changes in several key biological processes (cell cycle, cell division, mitosis), cardiac ion channels, and calcium handling genes. Gene-associated changes in ionic currents exhibited both linear trends and sudden shifts across developmental stages, with changes in calcium handling ( I NCX ) and repolarization ( I K1 ) most strongly associated with an age-dependent decrease in the action potential plateau potential and increase in triangulation, respectively. We also note a shift in repolarization reserve, with lower I Kr expression in younger patients, a finding likely tied to the increased amplitude of I Ks triggered by elevated sympathetic activation in pediatric patients. Conclusion This study provides valuable insights into age-dependent changes in human cardiac gene expression and electrophysiology among patients with CHD, shedding light on molecular mechanisms underlying cardiac development and function across different developmental stages.
Collapse
|
3
|
Cooper BL, Salameh S, Posnack NG. Comparative cardiotoxicity assessment of bisphenol chemicals and estradiol using human induced pluripotent stem cell-derived cardiomyocytes. Toxicol Sci 2024; 198:273-287. [PMID: 38310357 PMCID: PMC10964748 DOI: 10.1093/toxsci/kfae015] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2024] Open
Abstract
Bisphenol A (BPA) is commonly used to manufacture consumer and medical-grade plastics. Due to health concerns, BPA substitutes are being incorporated-including bisphenol S (BPS) and bisphenol F (BPF)-without a comprehensive understanding of their toxicological profile. Previous studies suggest that bisphenol chemicals perturb cardiac electrophysiology in a manner that is similar to 17β-estradiol (E2). We aimed to compare the effects of E2 with BPA, BPF, and BPS using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM). Cardiac parameters were evaluated using microelectrode array (MEA) technology and live-cell fluorescent imaging. Cardiac metrics remained relatively stable after exposure to nanomolar concentrations (1-1000 nM) of E2, BPA, BPF, or BPS. At higher micromolar concentrations, chemical exposures decreased the depolarization spike amplitude, and shortened the field potential, action potential duration, and calcium transient duration (E2 ≥ BPA ≥ BPF ≫ BPS). Cardiomyocyte physiology was largely undisturbed by BPS. BPA-induced effects were exaggerated when coadministered with an L-type calcium channel (LTCC) antagonist or E2, and reduced when coadministered with an LTCC agonist or an estrogen receptor alpha antagonist. E2-induced effects were not exaggerated by coadministration with an LTCC antagonist. Although the observed cardiac effects of E2 and BPA were similar, a few distinct differences suggest that these chemicals may act (in part) through different mechanisms. hiPSC-CM are a useful model for screening cardiotoxic chemicals, nevertheless, the described findings should be validated using a more complex ex vivo and/or in vivo model.
Collapse
Affiliation(s)
- Blake L Cooper
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Department of Pharmacology & Physiology, School of Medicine & Health Sciences, The George Washington University, Washington, District of Columbia 20052, USA
| | - Shatha Salameh
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Department of Pharmacology & Physiology, School of Medicine & Health Sciences, The George Washington University, Washington, District of Columbia 20052, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Department of Pharmacology & Physiology, School of Medicine & Health Sciences, The George Washington University, Washington, District of Columbia 20052, USA
- Department of Pediatrics, School of Medicine & Health Sciences, The George Washington University, Washington, District of Columbia 20052, USA
| |
Collapse
|
4
|
Yu Z, Iyer L, Swiercz AP, Paronett E, Ramadan M, Marvar PJ, Posnack NG. The Impact of Chronic Phthalate Exposure on Rodent Anxiety and Cognition. Biol Psychiatry Glob Open Sci 2024; 4:203-212. [PMID: 38298799 PMCID: PMC10829632 DOI: 10.1016/j.bpsgos.2023.07.002] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/29/2023] [Accepted: 07/01/2023] [Indexed: 02/02/2024] Open
Abstract
Background There is a growing importance for environmental contributions to psychiatric disorders and understanding the impact of the exposome (i.e., pollutants and toxins). For example, increased biomonitoring and epidemiological studies suggest that daily phthalate chemical exposure contributes to neurological and behavioral abnormalities; however, these mechanisms remain poorly understood. Therefore, the current study was aimed at examining the effects of chronic phthalate exposure on rodent anxiety behaviors and cognition and the impact on hypothalamic-pituitary-adrenal axis function. Methods Adult male mice (C57BL6/J) were administered MEHP via drinking water (1 mg/mL), and anxiety-like behavior and cognition combined with hypothalamic-pituitary-adrenal axis and inflammatory assays were assessed after 3 weeks of MEHP exposure. Results MEHP-treated mice exhibited enhanced generalized anxiety-like behaviors, as demonstrated by reduced time spent in the open-arm of the elevated plus maze and center exploration in the open field. Tests of spatial memory and cognition were unchanged. Following MEHP administration, circulating levels of corticosterone and proinflammatory cytokines were significantly increased, while at the tissue level, there were MEHP-dependent reductions in glucocorticoid metabolism genes Hsd11b1 and Hsd11b2. Conclusions These data suggest that chronic MEHP exposure leads to enhanced generalized anxiety behaviors independent of rodent measures of cognition and memory, which may be driven by MEHP-dependent effects on hypothalamic-pituitary-adrenal axis and peripheral glucocorticoid metabolism function.
Collapse
Affiliation(s)
- Zhe Yu
- Department of Pharmacology and Physiology, George Washington University, Washington, DC
| | - Laxmi Iyer
- Department of Anatomy, Physiology and Genetics, Uniformed Services University Health Sciences, Bethesda, Maryland
| | - Adam P. Swiercz
- National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Elizabeth Paronett
- Department of Pharmacology and Physiology, George Washington University, Washington, DC
| | - Manelle Ramadan
- Children’s National Heart Institute, Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC
| | - Paul J. Marvar
- Department of Pharmacology and Physiology, George Washington University, Washington, DC
- Department of Psychiatry and Behavioral Sciences, George Washington University, Washington, DC
| | - Nikki Gillum Posnack
- Department of Pharmacology and Physiology, George Washington University, Washington, DC
- Children’s National Heart Institute, Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC
| |
Collapse
|
5
|
Swift LM, Roberts A, Pressman J, Guerrelli D, Allen S, Haq KT, Reisz JA, D’Alessandro A, Posnack NG. Evidence for the cardiodepressive effects of the plasticizer di-2-ethylhexyl phthalate. Toxicol Sci 2023; 197:79-94. [PMID: 37812252 PMCID: PMC10734602 DOI: 10.1093/toxsci/kfad105] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023] Open
Abstract
Di-2-ethylhexyl phthalate (DEHP) is commonly used in the manufacturing of plastic materials, including intravenous bags, blood storage bags, and medical-grade tubing. DEHP can leach from plastic medical products, which can result in inadvertent patient exposure. DEHP concentrations were measured in red blood cell units stored between 7 and 42 days (17-119 μg/ml). Using these concentrations as a guide, Langendorff-perfused rat heart preparations were acutely exposed to DEHP. Sinus activity remained stable with lower doses of DEHP (25-50 μg/ml), but sinus rate declined by 43% and sinus node recovery time (SNRT) prolonged by 56.5% following 30-min exposure to 100 μg/ml DEHP. DEHP exposure also exerted a negative dromotropic response, as indicated by a 69.4% longer PR interval, 108.5% longer Wenckebach cycle length (WBCL), and increased incidence of atrioventricular (AV) uncoupling (60-min exposure). Pretreatment with doxycycline partially rescued the effects of DEHP on sinus activity, but did not ameliorate the effects on AV conduction. DEHP exposure also prolonged the ventricular action potential and effective refractory period, but had no measurable effect on intracellular calcium transient duration. Follow-up studies using human-induced pluripotent stem cell-derived cardiomyocytes confirmed that DEHP slows electrical conduction in a time (15 min-3 h) and dose-dependent manner (10-100 μg/ml). Previous studies have suggested that phthalate toxicity is specifically attributed to metabolites of DEHP, including mono-2-ethylhexylphthalate. This study demonstrates that DEHP exposure also contributes to cardiac dysfunction in a dose- and time-dependent manner. Future work is warranted to investigate the impact of DEHP (and its metabolites) on human health, with special consideration for clinical procedures that employ plastic materials.
Collapse
Affiliation(s)
- Luther M Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
| | - Anysja Roberts
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
| | - Jenna Pressman
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Department of Biomedical Engineering, School of Engineering and Applied Sciences, The George Washington University, Washington, District of Columbia 20037, USA
| | - Devon Guerrelli
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Department of Biomedical Engineering, School of Engineering and Applied Sciences, The George Washington University, Washington, District of Columbia 20037, USA
| | - Samuel Allen
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
| | - Kazi T Haq
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado, Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Angelo D’Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado, Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, District of Columbia 20010, USA
- Department of Pediatrics, School of Medicine and Health Sciences, The George Washington University, Washington, District of Columbia 20037, USA
- Department of Pharmacology & Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, District of Columbia 20037, USA
| |
Collapse
|
6
|
Cooper BL, Salameh S, Posnack NG. Comparative cardiotoxicity assessment of bisphenol chemicals and estradiol using human induced pluripotent stem cell-derived cardiomyocytes. bioRxiv 2023:2023.09.13.557564. [PMID: 37745451 PMCID: PMC10515916 DOI: 10.1101/2023.09.13.557564] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Background Bisphenol A (BPA) is commonly used to manufacture consumer and medical-grade plastics. Due to health concerns, BPA substitutes are being incorporated - including bisphenol S (BPS) and bisphenol F (BPF) - without a comprehensive understanding of their toxicological profile. Objective Previous studies suggest that bisphenol chemicals perturb cardiac electrophysiology in a manner that is similar to 17β-estradiol (E2). We aimed to compare the effects of E2 with BPA, BPF, and BPS using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM). Methods Cardiac parameters were evaluated using microelectrode array (MEA) technology and live-cell fluorescent imaging at baseline and in response to chemical exposure (0.001-100 μM). Results Cardiac metrics remained relatively stable after exposure to nanomolar concentrations (1-1,000 nM) of E2, BPA, BPF, or BPS. At higher micromolar concentrations, chemical exposures resulted in a decrease in the depolarizing spike amplitude, shorter field potential and action potential duration, shorter calcium transient duration, and decrease in hiPSC-CM contractility (E2 > BPA > BPF >> BPS). Cardiomyocyte physiology was largely undisturbed by BPS exposure. BPA-induced effects were exaggerated when co-administered with an L-type calcium channel antagonist (verapamil) or E2 - and reduced when co-administered with an L-type calcium channel agonist (Bay K8644) or an estrogen receptor alpha antagonist (MPP). E2-induced effects generally mirrored those of BPA, but were not exaggerated by co-administration with an L-type calcium channel antagonist. Discussion Collectively across multiple cardiac endpoints, E2 was the most potent and BPS was the least potent disruptor of hiPSC-CM function. Although the observed cardiac effects of E2 and BPA were similar, a few distinct differences suggest that these chemicals may act (in part) through different mechanisms. hiPSC-CM are a useful model for screening cardiotoxic chemicals, nevertheless, the described in vitro findings should be validated using a more complex ex vivo and/or in vivo model.
Collapse
|
7
|
Swift LM, Roberts A, Pressman J, Guerrelli D, Allen S, Haq KT, Reisz JA, D'Alessandro A, Posnack NG. Evidence for the cardiodepressive effects of the plasticizer di-2-ethylhexylphthalate (DEHP). bioRxiv 2023:2023.05.22.541729. [PMID: 37293060 PMCID: PMC10245927 DOI: 10.1101/2023.05.22.541729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Di-2-ethylhexylphthalate (DEHP) is commonly used in the manufacturing of plastic materials, including intravenous bags, blood storage bags, and medical-grade tubing. DEHP can leach from plastic medical products, which can result in inadvertent patient exposure. DEHP concentrations were measured in red blood cell (RBC) units stored between 7-42 days (23-119 μg/mL). Using these concentrations as a guide, Langendorff-perfused rat heart preparations were acutely exposed to DEHP. Sinus activity remained stable with lower doses of DEHP (25-50 μg/mL), but sinus rate declined by 43% and sinus node recovery time prolonged by 56.5% following 30-minute exposure to 100 μg/ml DEHP. DEHP exposure also exerted a negative dromotropic response, as indicated by a 69.4% longer PR interval, 108.5% longer Wenckebach cycle length, and increased incidence of atrioventricular uncoupling. Pretreatment with doxycycline partially rescued the effects of DEHP on sinus activity, but did not ameliorate the effects on atrioventricular conduction. DEHP exposure also prolonged the ventricular action potential and effective refractory period, but had no measurable effect on intracellular calcium transient duration. Follow-up studies using hiPSC-CM confirmed that DEHP slows electrical conduction in a time (15 min - 3 hours) and dose-dependent manner (10-100 μg/mL). Previous studies have suggested that phthalate toxicity is specifically attributed to metabolites of DEHP, including mono-2-ethylhexyl phthalate (MEHP). This study demonstrates that DEHP exposure also contributes to cardiac dysfunction in a dose- and time-dependent manner. Future work is warranted to investigate the impact of DEHP (and its metabolites) on human health, with special consideration for clinical procedures that employ plastic materials.
Collapse
|
8
|
Haq KT, Roberts A, Berk F, Allen S, Swift LM, Posnack NG. KairoSight-3.0: A validated optical mapping software to characterize cardiac electrophysiology, excitation-contraction coupling, and alternans. J Mol Cell Cardiol Plus 2023; 5:100043. [PMID: 37786807 PMCID: PMC10544851 DOI: 10.1016/j.jmccpl.2023.100043] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Background Cardiac optical mapping is an imaging technique that measures fluorescent signals across a cardiac preparation. Dual optical imaging of voltage-sensitive and calcium-sensitive probes allows for simultaneous recordings of cardiac action potentials and intracellular calcium transients with high spatiotemporal resolution. The analysis of these complex optical datasets is both time intensive and technically challenging; as such, we have developed a software package for semi-automated image processing and analysis. Herein, we report an updated version of our software package (KairoSight-3.0) with features to enhance the characterization of cardiac parameters using optical signals. Methods To test software validity and applicability, we used Langendorff-perfused heart preparations to record transmembrane voltage and intracellular calcium signals from the epicardial surface. Isolated hearts from guinea pigs and rats were loaded with a potentiometric dye (RH237) and/or calcium indicator dye (Rhod-2AM) and fluorescent signals were acquired. We used Python 3.8.5 programming language to develop the KairoSight-3.0 software. Cardiac maps were validated with a user-specified manual mapping approach. Results Manual maps of action potential duration (30 or 80 % repolarization), calcium transient duration (30 or 80 % reuptake), action potential and calcium transient alternans were constituted to validate the accuracy of software-generated maps. Manual and software maps had high accuracy, with >97 % of manual and software values falling within 10 ms of each other and >75 % within 5 ms for action potential duration and calcium transient duration measurements (n = 1000-2000 pixels). Further, our software package includes additional measurement tools to analyze signal-to-noise ratio, conduction velocity, action potential and calcium transient alternans, and action potential-calcium transient coupling time to produce physiologically meaningful optical maps. Conclusions KairoSight-3.0 has enhanced capabilities to perform measurements of cardiac electrophysiology, calcium handling, alternans, and the excitation-contraction coupling with satisfactory accuracy.
Collapse
Affiliation(s)
- Kazi T. Haq
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, DC 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC 20010, USA
| | - Anysja Roberts
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, DC 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC 20010, USA
| | - Fiona Berk
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, DC 20010, USA
- Department of Biomedical Engineering, School of Engineering and Applied Sciences: George Washington University, Washington, DC 20037, USA
| | - Samuel Allen
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, DC 20010, USA
| | - Luther M. Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, DC 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC 20010, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, DC 20010, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC 20010, USA
- Department of Pediatrics, Department of Pharmacology & Physiology, School of Medicine and Health Sciences: George Washington University, Washington, DC 20037, USA
| |
Collapse
|
9
|
Salameh S, Ogueri V, Posnack NG. Adapting to a new environment: postnatal maturation of the human cardiomyocyte. J Physiol 2023; 601:2593-2619. [PMID: 37031380 PMCID: PMC10775138 DOI: 10.1113/jp283792] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/16/2023] [Indexed: 04/10/2023] Open
Abstract
The postnatal mammalian heart undergoes remarkable developmental changes, which are stimulated by the transition from the intrauterine to extrauterine environment. With birth, increased oxygen levels promote metabolic, structural and biophysical maturation of cardiomyocytes, resulting in mature muscle with increased efficiency, contractility and electrical conduction. In this Topical Review article, we highlight key studies that inform our current understanding of human cardiomyocyte maturation. Collectively, these studies suggest that human atrial and ventricular myocytes evolve quickly within the first year but might not reach a fully mature adult phenotype until nearly the first decade of life. However, it is important to note that fetal, neonatal and paediatric cardiac physiology studies are hindered by a number of limitations, including the scarcity of human tissue, small sample size and a heavy reliance on diseased tissue samples, often without age-matched healthy controls. Future developmental studies are warranted to expand our understanding of normal cardiac physiology/pathophysiology and inform age-appropriate treatment strategies for cardiac disease.
Collapse
Affiliation(s)
- Shatha Salameh
- Department of Pharmacology & Physiology, George Washington University, Washington, DC, USA
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC, USA
| | - Vanessa Ogueri
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC, USA
| | - Nikki Gillum Posnack
- Department of Pharmacology & Physiology, George Washington University, Washington, DC, USA
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC, USA
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC, USA
- Department of Pediatrics, George Washington University, Washington, DC, USA
| |
Collapse
|
10
|
Haq KT, Roberts A, Berk F, Allen S, Swift LM, Posnack NG. KairoSight-3.0 : A Validated Optical Mapping Software to Characterize Cardiac Electrophysiology, Excitation-Contraction Coupling, and Alternans. bioRxiv 2023:2023.05.01.538926. [PMID: 37205349 PMCID: PMC10187248 DOI: 10.1101/2023.05.01.538926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Background Cardiac optical mapping is an imaging technique that measures fluorescent signals across a cardiac preparation. Dual optical mapping of voltage-sensitive and calcium-sensitive probes allow for simultaneous recordings of cardiac action potentials and intracellular calcium transients with high spatiotemporal resolution. The analysis of these complex optical datasets is both time intensive and technically challenging; as such, we have developed a software package for semi-automated image processing and analysis. Herein, we report an updated version of our software package ( KairoSight-3 . 0 ) with features to enhance characterization of cardiac parameters using optical signals. Methods To test software validity and applicability, we used Langendorff-perfused heart preparations to record transmembrane voltage and intracellular calcium signals from the epicardial surface. Isolated hearts from guinea pigs and rats were loaded with a potentiometric dye (RH237) and/or calcium indicator dye (Rhod-2AM) and fluorescent signals were acquired. We used Python 3.8.5 programming language to develop the KairoSight-3 . 0 software. Cardiac maps were validated with a user-specified manual mapping approach. Results Manual maps of action potential duration (30 or 80% repolarization), calcium transient duration (30 or 80% reuptake), action potential and calcium transient alternans were constituted to validate the accuracy of software-generated maps. Manual and software maps had high accuracy, with >97% of manual and software values falling within 10 ms of each other and >75% within 5 ms for action potential duration and calcium transient duration measurements (n=1000-2000 pixels). Further, our software package includes additional cardiac metric measurement tools to analyze signal-to-noise ratio, conduction velocity, action potential and calcium transient alternans, and action potential-calcium transient coupling time to produce physiologically meaningful optical maps. Conclusions KairoSight-3 . 0 has enhanced capabilities to perform measurements of cardiac electrophysiology, calcium handling, and the excitation-contraction coupling with satisfactory accuracy. Graphical Abstract Demonstrating Experimental and Data Analysis Workflow Created with Biorender.com.
Collapse
|
11
|
Guerrelli D, Desai M, Semaan Y, Essa Y, Zurakowski D, Cendali FI, Reisz JA, D'Alessandro A, Luban NC, Posnack NG. Prevalence and Clinical Implications of Heightened Plastic Chemical Exposure in Pediatric Patients Undergoing Cardiopulmonary Bypass. medRxiv 2023:2023.05.02.23289379. [PMID: 37205364 PMCID: PMC10187441 DOI: 10.1101/2023.05.02.23289379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Importance Phthalate chemicals are used to manufacture disposable plastic medical products, including blood storage bags and components of cardiopulmonary bypass (CPB) circuits. During cardiac surgery, patients can be inadvertently exposed to phthalate chemicals that are released from these plastic products. Objective To quantify iatrogenic phthalate chemical exposure in pediatric patients undergoing cardiac surgery, and examine the link between phthalate exposure and post-operative outcomes. Design Setting and Participants The study cohort included 122 pediatric patients undergoing cardiac surgery at Children's National Hospital. For each patient, a single plasma sample was collected pre-operatively and two additional samples were collected post-operatively upon return from the operating room (post-operative day 0) and the morning after surgery (post-operative day 1). Exposures Concentrations of di(2-ethylhexyl)phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry. Main Outcomes and Measures Plasma concentrations of phthalates, post-operative blood gas measurements, and post-operative complications. Results Study subjects were subdivided into three groups, according to surgical procedure: 1) cardiac surgery not requiring CPB support, 2) cardiac surgery requiring CPB with crystalloid prime, and 3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience post-operative complications, including arrhythmias, low cardiac output syndrome, and additional post-operative interventions. RBC washing was an effective strategy to reduce DEHP levels in CPB prime. Conclusions and Relevance Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure. Key Points Question: Is cardiac surgery with cardiopulmonary bypass a significant source of phthalate chemical exposure in pediatric patients?Findings: In this study of 122 pediatric cardiac surgery patients, phthalate metabolites were quantified from blood samples before and after surgery. Phthalate concentrations were highest in patients undergoing cardiopulmonary bypass with red blood cell-based prime. Heightened phthalate exposure was associated with post-operative complications.Meaning: Cardiopulmonary bypass is a significant source of phthalate chemical exposure, and patients with heightened exposure may be at greater risk for postoperative cardiovascular complications.
Collapse
|
12
|
Yu Z, Iyer L, Swiercz AP, Paronett E, Ramadan M, Marvar PJ, Posnack NG. The Impact of Chronic Phthalate Exposure on Rodent Anxiety and Cognition. bioRxiv 2023:2023.04.13.536567. [PMID: 37886449 PMCID: PMC10602041 DOI: 10.1101/2023.04.13.536567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
There is a growing importance for environmental contributions to psychiatric disorders and understanding the impact of the exposome (i.e., pollutants and toxins). Increased biomonitoring and epidemiological studies, for example, suggest that daily phthalate chemical exposure contribute to neurological and behavioral abnormalities, however these mechanisms remain poorly understood. The current study therefore aimed to examine the effects of chronic phthalate exposure on rodent anxiety behaviors, cognition, and the impact on hypothalamic-pituitary- adrenal (HPA)-axis function. Adult male mice (C57BL6/J) were administered mono-2-ethylhexyl phthalate (MEHP) via drinking water (1 mg/ml), and anxiety-like behavior, cognition combined with HPA- axis and inflammatory assays were assessed after 3 weeks of MEHP exposure. MEHP-treated mice exhibited enhanced generalized anxiety-like behaviors, as demonstrated by reduced time spent in the open-arm of the elevated plus maze (EPM) and center exploration in the open field (OF). Tests of spatial, cognition and memory function were unchanged. Following MEHP administration, circulating levels of corticosterone and pro- inflammatory cytokines were significantly increased, while at the tissue level, MEHP-dependent reductions in glucocorticoid metabolism genes 11β-hydroxysteroid dehydrogenase (11β-HSD) 1 and 2. These data suggest that chronic MEHP exposure leads to enhanced generalized-anxiety behaviors independent of rodent measures of cognition and memory, which maybe driven by MEHP-dependent effects on HPA-axis and peripheral glucocorticoid metabolism function.
Collapse
|
13
|
Cooper BL, Posnack NG. Choice of experimental model determines translational impact: The link between bisphenol A and cardiotoxicity. Food Chem Toxicol 2023; 174:113667. [PMID: 36791906 PMCID: PMC10441008 DOI: 10.1016/j.fct.2023.113667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 02/11/2023] [Indexed: 02/15/2023]
Affiliation(s)
- Blake L Cooper
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, United States; Children's National Heart Institute, Children's National Hospital, Washington, DC, United States; Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, United States; Children's National Heart Institute, Children's National Hospital, Washington, DC, United States; Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States; Department of Pediatrics, The George Washington University, Washington, DC, United States.
| |
Collapse
|
14
|
Haq KT, Cooper BL, Berk F, Posnack NG. The effect of sex and age on ex vivo cardiac electrophysiology: insight from a guinea pig model. Am J Physiol Heart Circ Physiol 2023; 324:H141-H154. [PMID: 36487188 PMCID: PMC9829463 DOI: 10.1152/ajpheart.00497.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/14/2022]
Abstract
Highlighting the importance of sex as a biological variable, we recently reported sex differences in guinea pig in vivo electrocardiogram (ECG) measurements. However, substantial inconsistencies exist in this animal model, with conflicting reports of sex-specific differences in cardiac electrophysiology observed in vivo and in vitro. Herein, we evaluated whether sexual dimorphism persists in ex vivo preparations, using an isolated intact heart preparation. Pseudo-ECG recordings were collected in conjunction with dual optical mapping of transmembrane voltage and intracellular calcium from Langendorff-perfused hearts. In contrast to our in vivo results, we did not observe sex-specific differences in ECG parameters collected from isolated hearts. Furthermore, we observed significant age-specific differences in action potential duration (APD) and Ca2+ transient duration (CaD) during both normal sinus rhythm (NSR) and in response to dynamic pacing but only a modest sex-specific difference in CaD30. Similarly, the alternans fluctuation coefficient, conduction velocity during sinus rhythm or in response to pacing, and electrophysiology parameters (atrioventricular nodal effective refractory period, Wenckebach cycle length) were comparable between males and females. Results of our study suggest that the observed sex-specific differences in in vivo ECG parameters from guinea pigs are diminished in ex vivo isolated heart preparations, although age-specific patterns are prevalent. To assess sex as a biological variable in cardiac electrophysiology, a comprehensive approach may be necessary using both in vitro measurements from cardiomyocyte or intact heart preparations with secondary follow-up in vivo studies.NEW & NOTEWORTHY We evaluated whether the guinea pig heart has intrinsic sex-specific differences in cardiac electrophysiology. Although we observed sex-specific differences in in vivo ECGs, these differences did not persist ex vivo. Using a whole heart model, we observed similar APD, CaD, conduction velocity, and alternans susceptibility in males and females. We conclude that sex-specific differences in guinea pig cardiac electrophysiology are likely influenced by the in vivo environment and less dependent on the intrinsic electrical properties of the heart.
Collapse
Affiliation(s)
- Kazi T Haq
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia
| | - Blake L Cooper
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia
- Department of Pharmacology and Physiology, The George Washington University, Washington, District of Columbia
| | - Fiona Berk
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia
- Department of Pharmacology and Physiology, The George Washington University, Washington, District of Columbia
- Department of Biomedical Engineering, The George Washington University, Washington, District of Columbia
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia
- Department of Pharmacology and Physiology, The George Washington University, Washington, District of Columbia
- Department of Pediatrics, The George Washington University, Washington, District of Columbia
| |
Collapse
|
15
|
Haq KT, Cooper BL, Berk F, Roberts A, Swift LM, Posnack NG. Demographic and Methodological Heterogeneity in Electrocardiogram Signals From Guinea Pigs. Front Physiol 2022; 13:925042. [PMID: 35721548 PMCID: PMC9202081 DOI: 10.3389/fphys.2022.925042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/09/2022] [Indexed: 11/24/2022] Open
Abstract
Electrocardiograms (ECG) are universally used to measure the electrical activity of the heart; however, variations in recording techniques and/or subject demographics can affect ECG interpretation. In this study, we investigated variables that are likely to influence ECG metric measurements in cardiovascular research, including recording technique, use of anesthesia, and animal model characteristics. Awake limb lead ECG recordings were collected in vivo from adult guinea pigs using a platform ECG system, while recordings in anesthetized animals were performed using both a platform and needle ECG system. We report significant heterogeneities in ECG metric values that are attributed to methodological differences (e.g., ECG lead configuration, ECG recording platform, presence or absence of anesthesia) that persist even within the same cohort of animals. Further, we report that variability in animal demographics is preserved in vivo ECG recordings—with animal age serving as a significant contributor, while sex-specific influences were less pronounced. Methodological approaches and subject demographics should be fully considered when interpreting ECG values in animal models, comparing datasets between studies, or developing artificial intelligence algorithms that utilize an ECG database.
Collapse
Affiliation(s)
- Kazi T. Haq
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington D.C., DC, United States
- Children’s National Heart Institute, Washington D.C., DC, United States
| | - Blake L. Cooper
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington D.C., DC, United States
- Children’s National Heart Institute, Washington D.C., DC, United States
- Department of Pharmacology & Physiology, Washington D.C., DC, United States
| | - Fiona Berk
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington D.C., DC, United States
| | - Anysja Roberts
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington D.C., DC, United States
- Children’s National Heart Institute, Washington D.C., DC, United States
| | - Luther M. Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington D.C., DC, United States
- Children’s National Heart Institute, Washington D.C., DC, United States
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington D.C., DC, United States
- Children’s National Heart Institute, Washington D.C., DC, United States
- Department of Pharmacology & Physiology, Washington D.C., DC, United States
- Department of Pediatrics, Washington D.C., DC, United States
- *Correspondence: Nikki Gillum Posnack,
| |
Collapse
|
16
|
Cooper BL, Posnack NG. Characteristics of Bisphenol Cardiotoxicity: Impaired Excitability, Contractility, and Relaxation. Cardiovasc Toxicol 2022; 22:273-280. [PMID: 35143014 PMCID: PMC9204785 DOI: 10.1007/s12012-022-09719-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/04/2022] [Indexed: 12/14/2022]
Abstract
Bisphenol a (BPA) is a high production volume chemical that is frequently used to manufacture epoxy resins and polycarbonate plastics. BPA-containing products are now pervasive, and as a result, biomonitoring studies report widespread exposure in > 90% of adults, adolescents, and children. Both epidemiological and experimental studies have reported associations between BPA exposure and adverse cardiovascular health outcomes. With increasing concerns regarding BPA exposure, a few structurally similar bisphenol chemicals have been introduced as replacements, including bisphenol s (BPS) and bisphenol f (BPF). In accordance with the recently established "Key characteristics of cardiovascular toxicants", we reviewed the literature to highlight the immediate effects of bisphenol chemicals on (1) cardiac excitability, and (2) contractility and relaxation. BPA inhibits key cardiac ion channels, impairs cardiac excitability, and acts as a more potent inhibitor as compared to BPF and BPS. Through the inhibition of calcium current, some studies report that bisphenol chemicals can act as negative inotropic agents. Yet, others suggest that low dose exposures may increase contractility and precipitate triggered arrhythmias via the phosphorylation of key calcium handling proteins. Accordingly, we propose additional considerations for future work to comprehensively address the cardiac safety profile of BPA, as compared to replacement chemicals.
Collapse
Affiliation(s)
- Blake L. Cooper
- Children’s National Heart Institute, Children’s National Hospital, Washington, DC 20010, USA,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC 20010, USA,Department of Pharmacology & Physiology, George Washington University, Washington, DC 20037, USA
| | - Nikki Gillum Posnack
- Children's National Heart Institute, Children's National Hospital, Washington, DC, 20010, USA. .,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, 20010, USA. .,Department of Pediatrics, George Washington University, Washington, DC, 20037, USA. .,Department of Pharmacology & Physiology, George Washington University, Washington, DC, 20037, USA.
| |
Collapse
|
17
|
Sinha P, Nuszkowski M, Burke M, Posnack NG. Irradiated red blood cells: Can all sins be washed away? Transfusion 2022; 62:252-253. [PMID: 35023158 PMCID: PMC9212561 DOI: 10.1111/trf.16738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 10/04/2021] [Accepted: 10/26/2021] [Indexed: 01/03/2023]
Affiliation(s)
- Pranava Sinha
- Division of Cardiac Surgery, Children's National Hospital, Washington, DC, USA,School of Medicine, The George Washington University, Washington, DC, USA
| | - Mark Nuszkowski
- Division of Cardiac Surgery, Children's National Hospital, Washington, DC, USA
| | - Morgan Burke
- School of Medicine, The George Washington University, Washington, DC, USA
| | - Nikki Gillum Posnack
- School of Medicine, The George Washington University, Washington, DC, USA,Children's National Hospital, Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington, DC, USA
| |
Collapse
|
18
|
Abstract
Optical mapping is an imaging technique that is extensively used in cardiovascular research, wherein parameter-sensitive fluorescent indicators are used to study the electrophysiology and excitation-contraction coupling of cardiac tissues. Despite many benefits of optical mapping, eliminating motion artifacts within the optical signals is a major challenge, as myocardial contraction interferes with the faithful acquisition of action potentials and intracellular calcium transients. As such, excitation-contraction uncoupling agents are frequently used to reduce signal distortion by suppressing contraction. When compared with other uncoupling agents, blebbistatin is the most frequently used, as it offers increased potency with minimal direct effects on cardiac electrophysiology. Nevertheless, blebbistatin may exert secondary effects on electrical activity, metabolism, and coronary flow, and the incorrect administration of blebbistatin to cardiac tissue can prove detrimental, resulting in erroneous interpretation of optical mapping results. In this "Getting It Right" perspective, we briefly review the literature regarding the use of blebbistatin in cardiac optical mapping experiments, highlight potential secondary effects of blebbistatin on cardiac electrical activity and metabolic demand, and conclude with the consensus of the authors on best practices for effectively using blebbistatin in optical mapping studies of cardiac tissue.
Collapse
Affiliation(s)
- Luther M Swift
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia
| | - Matthew W Kay
- Department of Biomedical Engineering, George Washington University, Washington, District of Columbia
| | | | - Nikki Gillum Posnack
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia.,Department of Pediatrics, George Washington University, Washington, District of Columbia.,Department of Pharmacology and Physiology, George Washington University, Washington, District of Columbia
| |
Collapse
|
19
|
Posnack NG. Cardiac toxicity from bisphenol A: Are electrophysiology and calcium handling perturbations dose-dependent? Toxicol Appl Pharmacol 2021; 431:115740. [PMID: 34619161 DOI: 10.1016/j.taap.2021.115740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Affiliation(s)
- Nikki Gillum Posnack
- Children's National Hospital, Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Heart Institute, Washington, DC, United States; George Washington University, Department of Pharmacology & Physiology, Department of Pediatrics, Washington, DC, United States.
| |
Collapse
|
20
|
Lind L, Araujo JA, Barchowsky A, Belcher S, Berridge BR, Chiamvimonvat N, Chiu WA, Cogliano VJ, Elmore S, Farraj AK, Gomes AV, McHale CM, Meyer-Tamaki KB, Posnack NG, Vargas HM, Yang X, Zeise L, Zhou C, Smith MT. Key Characteristics of Cardiovascular Toxicants. Environ Health Perspect 2021; 129:95001. [PMID: 34558968 PMCID: PMC8462506 DOI: 10.1289/ehp9321] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND The concept of chemical agents having properties that confer potential hazard called key characteristics (KCs) was first developed to identify carcinogenic hazards. Identification of KCs of cardiovascular (CV) toxicants could facilitate the systematic assessment of CV hazards and understanding of assay and data gaps associated with current approaches. OBJECTIVES We sought to develop a consensus-based synthesis of scientific evidence on the KCs of chemical and nonchemical agents known to cause CV toxicity along with methods to measure them. METHODS An expert working group was convened to discuss mechanisms associated with CV toxicity. RESULTS The group identified 12 KCs of CV toxicants, defined as exogenous agents that adversely interfere with function of the CV system. The KCs were organized into those primarily affecting cardiac tissue (numbers 1-4 below), the vascular system (5-7), or both (8-12), as follows: 1) impairs regulation of cardiac excitability, 2) impairs cardiac contractility and relaxation, 3) induces cardiomyocyte injury and death, 4) induces proliferation of valve stroma, 5) impacts endothelial and vascular function, 6) alters hemostasis, 7) causes dyslipidemia, 8) impairs mitochondrial function, 9) modifies autonomic nervous system activity, 10) induces oxidative stress, 11) causes inflammation, and 12) alters hormone signaling. DISCUSSION These 12 KCs can be used to help identify pharmaceuticals and environmental pollutants as CV toxicants, as well as to better understand the mechanistic underpinnings of their toxicity. For example, evidence exists that fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] air pollution, arsenic, anthracycline drugs, and other exogenous chemicals possess one or more of the described KCs. In conclusion, the KCs could be used to identify potential CV toxicants and to define a set of test methods to evaluate CV toxicity in a more comprehensive and standardized manner than current approaches. https://doi.org/10.1289/EHP9321.
Collapse
Affiliation(s)
- Lars Lind
- Department of Medical Sciences, Clinical Epidemiology, University of Uppsala, Sweden
| | - Jesus A. Araujo
- Division of Cardiology, David Geffen School of Medicine at University of California Los Angeles (UCLA), UCLA, Los Angeles, California, USA
- Department of Environmental Health Sciences, Fielding School of Public Health and Molecular Biology Institute, UCLA, Los Angeles, California, USA
| | - Aaron Barchowsky
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pennsylvania, USA
| | - Scott Belcher
- Department of Biological Sciences, North Carolina State University, North Carolina, USA
| | - Brian R. Berridge
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Nipavan Chiamvimonvat
- Department of Internal Medicine, University of California, Davis, Davis, California, USA
| | - Weihsueh A. Chiu
- College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Vincent J. Cogliano
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Sarah Elmore
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Aimen K. Farraj
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, U.S. EPA, Research Triangle Park, North Carolina, USA
| | - Aldrin V. Gomes
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, California, USA
| | - Cliona M. McHale
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | | | - Nikki Gillum Posnack
- Children’s National Heart Institute and the Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC, USA
| | - Hugo M. Vargas
- Translational Safety & Bioanalytical Sciences, Amgen, Inc., Thousand Oaks, California, USA
| | - Xi Yang
- Division of Pharmacology and Toxicology, Office of Cardiology, Hematology, Endocrinology, and Nephrology, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Changcheng Zhou
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Martyn T. Smith
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| |
Collapse
|
21
|
Prudencio TM, Swift LM, Guerrelli D, Cooper B, Reilly M, Ciccarelli N, Sheng J, Jaimes R, Posnack NG. Bisphenol S and bisphenol F are less disruptive to cardiac electrophysiology, as compared to bisphenol A. Toxicol Sci 2021; 183:214-226. [PMID: 34240201 DOI: 10.1093/toxsci/kfab083] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Bisphenol A (BPA) is a high-production volume chemical used to manufacture consumer and medical-grade plastic products. Due to its ubiquity, the general population can incur daily environmental exposure to BPA, while heightened exposure has been reported in intensive care patients and industrial workers. Due to health concerns, structural analogues are being explored as replacements for BPA. This study aimed to examine the direct effects of BPA on cardiac electrophysiology compared with recently developed alternatives, including BPS (bisphenol S) and BPF (bisphenol F). Whole-cell voltage-clamp recordings were performed on cell lines transfected to express the voltage-gated sodium channel (Nav1.5), L-type voltage-gated calcium channel (Cav1.2), or the rapidly activating delayed rectifier potassium channel (hERG). Cardiac electrophysiology parameters were measured using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) and intact, whole rat heart preparations. BPA was the most potent inhibitor of fast/peak (INa-P) and late (INa-L) sodium channel (IC50= 55.3, 23.6 µM, respectively), L-type calcium channel (IC50= 30.8 µM) and hERG channel current (IC50= 127 µM). Inhibitory effects on L-type calcium channels were supported by microelectrode array recordings, which revealed a shortening of the extracellular field potential (akin to QT interval). BPA and BPF exposures slowed atrioventricular (AV) conduction and increased AV node refractoriness in isolated rat heart preparations, in a dose-dependent manner (BPA: +9.2% 0.001 µM, +95.7% 100 µM; BPF: +20.7% 100 µM). BPS did not alter any of the cardiac electrophysiology parameters tested. Results of this study demonstrate that BPA and BPF exert an immediate inhibitory effect on cardiac ion channels, while BPS is markedly less potent. Additional studies are necessary to fully elucidate the safety profile of bisphenol analogues on the heart.
Collapse
Affiliation(s)
- Tomas M Prudencio
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
| | - Luther M Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
| | - Devon Guerrelli
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA.,Department of Biomedical Engineering, George Washington University, Washington DC, USA
| | - Blake Cooper
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA.,Department of Pharmacology & Physiology, George Washington University, Washington DC, USA
| | - Marissa Reilly
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
| | - Nina Ciccarelli
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
| | | | - Rafael Jaimes
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, USA.,Children's National Heart Institute, Children's National Hospital, Washington, DC, USA.,Department of Pharmacology & Physiology, George Washington University, Washington DC, USA.,Department of Pediatrics, George Washington University, Washington DC, USA
| |
Collapse
|
22
|
Romanowicz J, Guerrelli D, Dhari Z, Mulvany C, Reilly M, Swift L, Vasandani N, Ramadan M, Leatherbury L, Ishibashi N, Posnack NG. Chronic perinatal hypoxia delays cardiac maturation in a mouse model for cyanotic congenital heart disease. Am J Physiol Heart Circ Physiol 2021; 320:H1873-H1886. [PMID: 33739154 DOI: 10.1152/ajpheart.00870.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Compared with acyanotic congenital heart disease (CHD), cyanotic CHD has an increased risk of lifelong mortality and morbidity. These adverse outcomes may be attributed to delayed cardiomyocyte maturation, since the transition from a hypoxic fetal milieu to oxygen-rich postnatal environment is disrupted. We established a rodent model to replicate hypoxic myocardial conditions spanning perinatal development, and tested the hypothesis that chronic hypoxia impairs cardiac development. Pregnant mice were housed in hypoxia beginning at embryonic day 16. Pups stayed in hypoxia until postnatal day (P)8 when cardiac development is nearly complete. Global gene expression was quantified at P8 and at P30, after recovering in normoxia. Phenotypic testing included electrocardiogram, echocardiogram, and ex vivo electrophysiology study. Hypoxic P8 animals were 47% smaller than controls with preserved heart size. Gene expression was grossly altered by hypoxia at P8 (1,427 genes affected), but normalized after recovery (P30). Electrocardiograms revealed bradycardia and slowed conduction velocity in hypoxic animals at P8, with noticeable resolution after recovery (P30). Notable differences that persisted after recovery (P30) included a 65% prolongation in ventricular effective refractory period, sinus node dysfunction, 23% reduction in ejection fraction, and 16% reduction in fractional shortening in animals exposed to hypoxia. We investigated the impact of chronic hypoxia on the developing heart. Perinatal hypoxia was associated with changes in gene expression and cardiac function. Persistent changes to the electrophysiological substrate and contractile function warrant further investigation and may contribute to adverse outcomes observed in the cyanotic CHD population.NEW & NOTEWORTHY We utilized a new mouse model of chronic perinatal hypoxia to simulate the hypoxic myocardial conditions present in cyanotic congenital heart disease. Hypoxia caused numerous abnormalities in cardiomyocyte gene expression, the electrophysiologic substrate of the heart, and contractile function. Taken together, alterations observed in the neonatal period suggest delayed cardiac development immediately following hypoxia.
Collapse
Affiliation(s)
- Jennifer Romanowicz
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia
| | - Devon Guerrelli
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia.,Department of Biomedical Engineering, George Washington University, Washington, District of Columbia
| | - Zaenab Dhari
- Center for Neuroscience Research, Children's National Research Institute, Washington, District of Columbia
| | - Colm Mulvany
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia
| | - Marissa Reilly
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia
| | - Luther Swift
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia
| | - Nimisha Vasandani
- Center for Neuroscience Research, Children's National Research Institute, Washington, District of Columbia
| | - Manelle Ramadan
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia
| | - Linda Leatherbury
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia
| | - Nobuyuki Ishibashi
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia.,Center for Neuroscience Research, Children's National Research Institute, Washington, District of Columbia.,Department of Pediatrics, George Washington University, Washington, District of Columbia.,Department of Pharmacology & Physiology, George Washington University, Washington, District of Columbia
| | - Nikki Gillum Posnack
- Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Research Institute, Washington, District of Columbia.,Department of Pediatrics, George Washington University, Washington, District of Columbia.,Department of Pharmacology & Physiology, George Washington University, Washington, District of Columbia
| |
Collapse
|
23
|
Burke M, Sinha P, Luban NLC, Posnack NG. Transfusion-Associated Hyperkalemic Cardiac Arrest in Neonatal, Infant, and Pediatric Patients. Front Pediatr 2021; 9:765306. [PMID: 34778153 PMCID: PMC8586075 DOI: 10.3389/fped.2021.765306] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 09/29/2021] [Indexed: 01/05/2023] Open
Abstract
Red blood cell (RBC) transfusions are a life-saving intervention, with nearly 14 million RBC units transfused in the United States each year. However, the safety and efficacy of this procedure can be influenced by variations in the collection, processing, and administration of RBCs. Procedures or manipulations that increase potassium (K+) levels in stored blood products can also predispose patients to hyperkalemia and transfusion-associated hyperkalemic cardiac arrest (TAHCA). In this mini review, we aimed to provide a brief overview of blood storage, the red cell storage lesion, and variables that increase extracellular [K+]. We also summarize cases of TAHCA and identify potential mitigation strategies. Hyperkalemia and cardiac arrhythmias can occur in pediatric patients when RBCs are transfused quickly, delivered directly to the heart without time for electrolyte equilibration, or accumulate extracellular K+ due to storage time or irradiation. Advances in blood banking have improved the availability and quality of RBCs, yet, some patient populations are sensitive to transfusion-associated hyperkalemia. Future research studies should further investigate potential mitigation strategies to reduce the risk of TAHCA, which may include using fresh RBCs, reducing storage time after irradiation, transfusing at slower rates, implementing manipulations that wash or remove excess extracellular K+, and implementing restrictive transfusion strategies.
Collapse
Affiliation(s)
- Morgan Burke
- School of Medicine, George Washington University, Washington, DC, United States
| | - Pranava Sinha
- Department of Pediatrics, School of Medicine, George Washington University, Washington, DC, United States.,Division of Cardiac Surgery, Children's National Hospital, Washington, DC, United States.,Children's National Heart Institute, Children's National Hospital, Washington, DC, United States
| | - Naomi L C Luban
- Department of Pediatrics, School of Medicine, George Washington University, Washington, DC, United States.,Department of Pathology, School of Medicine, George Washington University, Washington, DC, United States.,Division of Hematology and Laboratory Medicine, Children's National Hospital, Washington, DC, United States
| | - Nikki Gillum Posnack
- Department of Pediatrics, School of Medicine, George Washington University, Washington, DC, United States.,Children's National Heart Institute, Children's National Hospital, Washington, DC, United States.,Department of Pharmacology & Physiology, School of Medicine, George Washington University, Washington, DC, United States.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC, United States
| |
Collapse
|
24
|
Reilly M, Bruno CD, Prudencio TM, Ciccarelli N, Guerrelli D, Nair R, Ramadan M, Luban NLC, Posnack NG. Potential Consequences of the Red Blood Cell Storage Lesion on Cardiac Electrophysiology. J Am Heart Assoc 2020; 9:e017748. [PMID: 33086931 PMCID: PMC7763412 DOI: 10.1161/jaha.120.017748] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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: 06/01/2020] [Accepted: 09/04/2020] [Indexed: 12/17/2022]
Abstract
Background The red blood cell (RBC) storage lesion is a series of morphological, functional, and metabolic changes that RBCs undergo following collection, processing, and refrigerated storage for clinical use. Since the biochemical attributes of the RBC unit shifts with time, transfusion of older blood products may contribute to cardiac complications, including hyperkalemia and cardiac arrest. We measured the direct effect of storage age on cardiac electrophysiology and compared it with hyperkalemia, a prominent biomarker of storage lesion severity. Methods and Results Donor RBCs were processed using standard blood-banking techniques. The supernatant was collected from RBC units, 7 to 50 days after donor collection, for evaluation using Langendorff-heart preparations (rat) or human induced pluripotent stem cell-derived cardiomyocytes. Cardiac parameters remained stable following exposure to "fresh" supernatant from red blood cell units (day 7: 5.8±0.2 mM K+), but older blood products (day 40: 9.3±0.3 mM K+) caused bradycardia (baseline: 279±5 versus day 40: 216±18 beats per minute), delayed sinus node recovery (baseline: 243±8 versus day 40: 354±23 ms), and increased the effective refractory period of the atrioventricular node (baseline: 77±2 versus day 40: 93±7 ms) and ventricle (baseline: 50±3 versus day 40: 98±10 ms) in perfused hearts. Beating rate was also slowed in human induced pluripotent stem cell-derived cardiomyocytes after exposure to older supernatant from red blood cell units (-75±9%, day 40 versus control). Similar effects on automaticity and electrical conduction were observed with hyperkalemia (10-12 mM K+). Conclusions This is the first study to demonstrate that "older" blood products directly impact cardiac electrophysiology, using experimental models. These effects are likely caused by biochemical alterations in the supernatant from red blood cell units that occur over time, including, but not limited to hyperkalemia. Patients receiving large volume and/or rapid transfusions may be sensitive to these effects.
Collapse
Affiliation(s)
- Marissa Reilly
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Children’s National Heart InstituteChildren’s National HospitalWashingtonDC
| | - Chantal D. Bruno
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Division of Critical Care MedicineChildren’s National HospitalWashingtonDC
| | - Tomas M. Prudencio
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Children’s National Heart InstituteChildren’s National HospitalWashingtonDC
| | - Nina Ciccarelli
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Children’s National Heart InstituteChildren’s National HospitalWashingtonDC
| | - Devon Guerrelli
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Children’s National Heart InstituteChildren’s National HospitalWashingtonDC
| | - Raj Nair
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
| | - Manelle Ramadan
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Children’s National Heart InstituteChildren’s National HospitalWashingtonDC
| | - Naomi L. C. Luban
- Division of Hematology and Laboratory MedicineChildren’s National HospitalWashingtonDC
- Department of PediatricsGeorge Washington UniversitySchool of MedicineWashingtonDC
- Department of PathologyGeorge Washington UniversitySchool of MedicineWashingtonDC
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical InnovationChildren’s National HospitalWashingtonDC
- Children’s National Heart InstituteChildren’s National HospitalWashingtonDC
- Department of PediatricsGeorge Washington UniversitySchool of MedicineWashingtonDC
- Department of Pharmacology & PhysiologyGeorge Washington UniversitySchool of MedicineWashingtonDC
| |
Collapse
|
25
|
Ramadan M, Cooper B, Posnack NG. Bisphenols and phthalates: Plastic chemical exposures can contribute to adverse cardiovascular health outcomes. Birth Defects Res 2020; 112:1362-1385. [PMID: 32691967 DOI: 10.1002/bdr2.1752] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 12/18/2022]
Abstract
Phthalates and bisphenols are high production volume chemicals that are used in the manufacturing of consumer and medical products. Given the ubiquity of bisphenol and phthalate chemicals in the environment, biomonitoring studies routinely detect these chemicals in 75-90% of the general population. Accumulating evidence suggests that such chemical exposures may influence human health outcomes, including cardiovascular health. These associations are particularly worrisome for sensitive populations, including fetal, infant and pediatric groups-with underdeveloped metabolic capabilities and developing organ systems. In the presented article, we aimed to review the literature on environmental and clinical exposures to bisphenols and phthalates, highlight experimental work that suggests that these chemicals may exert a negative influence on cardiovascular health, and emphasize areas of concern that relate to vulnerable pediatric groups. Gaps in our current knowledge are also discussed, so that future endeavors may resolve the relationship between chemical exposures and the impact on pediatric cardiovascular physiology.
Collapse
Affiliation(s)
- Manelle Ramadan
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia, USA.,Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia, USA
| | - Blake Cooper
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, District of Columbia, USA.,Children's National Heart Institute, Children's National Hospital, Washington, District of Columbia, USA.,Department of Pediatrics, George Washington University, School of Medicine, Washington, District of Columbia, USA.,Department of Pharmacology & Physiology, George Washington University, School of Medicine, Washington, District of Columbia, USA
| |
Collapse
|
26
|
Swift LM, Burke M, Guerrelli D, Reilly M, Ramadan M, McCullough D, Prudencio T, Mulvany C, Chaluvadi A, Jaimes R, Posnack NG. Age-dependent changes in electrophysiology and calcium handling: implications for pediatric cardiac research. Am J Physiol Heart Circ Physiol 2019; 318:H354-H365. [PMID: 31886723 DOI: 10.1152/ajpheart.00521.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Rodent models are frequently employed in cardiovascular research, yet our understanding of pediatric cardiac physiology has largely been deduced from more simplified two-dimensional cell studies. Previous studies have shown that postnatal development includes an alteration in the expression of genes and proteins involved in cell coupling, ion channels, and intracellular calcium handling. Accordingly, we hypothesized that postnatal cell maturation is likely to lead to dynamic alterations in whole heart electrophysiology and calcium handling. To test this hypothesis, we employed multiparametric imaging and electrophysiological techniques to quantify developmental changes from neonate to adult. In vivo electrocardiograms were collected to assess changes in heart rate, variability, and atrioventricular conduction (Sprague-Dawley rats). Intact, whole hearts were transferred to a Langendorff-perfusion system for multiparametric imaging (voltage, calcium). Optical mapping was performed in conjunction with an electrophysiology study to assess cardiac dynamics throughout development. Postnatal age was associated with an increase in the heart rate (181 ± 34 vs. 429 ± 13 beats/min), faster atrioventricular conduction (94 ± 13 vs. 46 ± 3 ms), shortened action potentials (APD80: 113 ± 18 vs. 60 ± 17 ms), and decreased ventricular refractoriness (VERP: 157 ± 45 vs. 57 ± 14 ms; neonatal vs. adults, means ± SD, P < 0.05). Calcium handling matured with development, resulting in shortened calcium transient durations (168 ± 18 vs. 117 ± 14 ms) and decreased propensity for calcium transient alternans (160 ± 18- vs. 99 ± 11-ms cycle length threshold; neonatal vs. adults, mean ± SD, P < 0.05). Results of this study can serve as a comprehensive baseline for future studies focused on pediatric disease modeling and/or preclinical testing.NEW & NOTEWORTHY This is the first study to assess cardiac electrophysiology and calcium handling throughout postnatal development, using both in vivo and whole heart models.
Collapse
Affiliation(s)
- Luther M Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia
| | - Morgan Burke
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia
| | - Devon Guerrelli
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia
| | - Marissa Reilly
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia
| | - Manelle Ramadan
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia
| | - Damon McCullough
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia
| | - Tomas Prudencio
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia
| | - Colm Mulvany
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia
| | - Ashika Chaluvadi
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia
| | - Rafael Jaimes
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia.,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia.,Department of Pediatrics and Department of Pharmacology and Physiology, School of Medicine and Health Sciences, George Washington University, Washington, District of Columbia
| |
Collapse
|
27
|
Swift LM, Jaimes R, McCullough D, Burke M, Reilly M, Maeda T, Zhang H, Ishibashi N, Rogers JM, Posnack NG. Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts. J Vis Exp 2019. [PMID: 31762469 DOI: 10.3791/60472] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Small animal models are most commonly used in cardiovascular research due to the availability of genetically modified species and lower cost compared to larger animals. Yet, larger mammals are better suited for translational research questions related to normal cardiac physiology, pathophysiology, and preclinical testing of therapeutic agents. To overcome the technical barriers associated with employing a larger animal model in cardiac research, we describe an approach to measure physiological parameters in an isolated, Langendorff-perfused piglet heart. This approach combines two powerful experimental tools to evaluate the state of the heart: electrophysiology (EP) study and simultaneous optical mapping of transmembrane voltage and intracellular calcium using parameter sensitive dyes (RH237, Rhod2-AM). The described methodologies are well suited for translational studies investigating the cardiac conduction system, alterations in action potential morphology, calcium handling, excitation-contraction coupling and the incidence of cardiac alternans or arrhythmias.
Collapse
Affiliation(s)
- Luther M Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital
| | - Rafael Jaimes
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital
| | - Damon McCullough
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital
| | - Morgan Burke
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital
| | - Marissa Reilly
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital
| | - Takuya Maeda
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital; Center for Neuroscience Research, Children's National Hospital
| | - Hanyu Zhang
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham
| | - Nobuyuki Ishibashi
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital; Center for Neuroscience Research, Children's National Hospital
| | - Jack M Rogers
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital; Children's National Heart Institute, Children's National Hospital; Department of Pediatrics, Department of Pharmacology & Physiology, School of Medicine and Health Sciences, George Washington University;
| |
Collapse
|
28
|
Jaimes R, McCullough D, Siegel B, Swift L, Hiebert J, Mclnerney D, Posnack NG. Lights, camera, path splitter: a new approach for truly simultaneous dual optical mapping of the heart with a single camera. BMC Biomed Eng 2019; 1. [PMID: 31768502 PMCID: PMC6876868 DOI: 10.1186/s42490-019-0024-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Background Optical mapping of transmembrane voltage and intracellular calcium is a powerful tool for investigating cardiac physiology and pathophysiology. However, simultaneous dual mapping of two fluorescent probes remains technically challenging. We introduce a novel, easy-to-use approach that requires a path splitter, single camera and excitation light to simultaneously acquire voltage and calcium signals from whole heart preparations, which can be applied to other physiological models – including neurons and isolated cardiomyocytes. Results Complementary probes were selected that could be excited with a single wavelength light source. Langendorff-perfused hearts (rat, swine) were stained and imaged using a sCMOS camera outfitted with an optical path splitter to simultaneously acquire two emission fields at high spatial and temporal resolution. Voltage (RH237) and calcium (Rhod2) signals were acquired concurrently on a single sensor, resulting in two 384 × 256 images at 814 frames per second. At this frame rate, the signal-to-noise ratio was 47 (RH237) and 85 (Rhod2). Imaging experiments were performed on small rodent hearts, as well as larger pig hearts with sufficient optical signals. In separate experiments, each dye was used independently to assess crosstalk and demonstrate signal specificity. Additionally, the effect of ryanodine on myocardial calcium transients was validated – with no measurable effect on the amplitude of optical action potentials. To demonstrate spatial resolution, ventricular tachycardia was induced –resulting in the novel finding that spatially discordant calcium alternans can be present in different regions of the heart, even when electrical alternans remain concordant. The described system excels in providing a wide field of view and high spatiotemporal resolution for a variety of cardiac preparations. Conclusions We report the first multiparametric mapping system that simultaneously acquires calcium and voltage signals from cardiac preparations, using a path splitter, single camera and excitation light. This approach eliminates the need for multiple cameras, excitation light patterning or frame interleaving. These features can aid in the adoption of dual mapping technology by the broader cardiovascular research community, and decrease the barrier of entry into panoramic heart imaging, as it reduces the number of required cameras. Electronic supplementary material The online version of this article (10.1186/s42490-019-0024-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Rafael Jaimes
- Sheikh Zayed Institute for Pediatric and Surgical Innovation: Children's National Health System, 6th floor, M7708, 111 Michigan Avenue NW, Washington, DC 20010, USA.,Children's National Heart Institute: Children's National Health System, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Damon McCullough
- Sheikh Zayed Institute for Pediatric and Surgical Innovation: Children's National Health System, 6th floor, M7708, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Bryan Siegel
- Children's National Heart Institute: Children's National Health System, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Luther Swift
- Sheikh Zayed Institute for Pediatric and Surgical Innovation: Children's National Health System, 6th floor, M7708, 111 Michigan Avenue NW, Washington, DC 20010, USA.,Children's National Heart Institute: Children's National Health System, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - James Hiebert
- Sheikh Zayed Institute for Pediatric and Surgical Innovation: Children's National Health System, 6th floor, M7708, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Daniel Mclnerney
- Sheikh Zayed Institute for Pediatric and Surgical Innovation: Children's National Health System, 6th floor, M7708, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric and Surgical Innovation: Children's National Health System, 6th floor, M7708, 111 Michigan Avenue NW, Washington, DC 20010, USA.,Children's National Heart Institute: Children's National Health System, 111 Michigan Avenue NW, Washington, DC 20010, USA.,Department of Pediatrics, Department of Pharmacology & Physiology, School of Medicine and Health Sciences: George Washington University, 2300 I Street NW, Washington, DC 20037, USA
| |
Collapse
|
29
|
Jaimes R, McCullough D, Siegel B, Swift L, McInerney D, Hiebert J, Perez-Alday EA, Trenor B, Sheng J, Saiz J, Tereshchenko LG, Posnack NG. Plasticizer Interaction With the Heart: Chemicals Used in Plastic Medical Devices Can Interfere With Cardiac Electrophysiology. Circ Arrhythm Electrophysiol 2019; 12:e007294. [PMID: 31248280 PMCID: PMC6693678 DOI: 10.1161/circep.119.007294] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Phthalates are used as plasticizers in the manufacturing of flexible, plastic medical products. Patients can be subjected to high phthalate exposure through contact with plastic medical devices. We aimed to investigate the cardiac safety and biocompatibility of mono-2-ethylhexyl phthalate (MEHP), a phthalate with documented exposure in intensive care patients. METHODS Optical mapping of transmembrane voltage and pacing studies were performed on isolated, Langendorff-perfused rat hearts to assess cardiac electrophysiology after MEHP exposure compared with controls. MEHP dose was chosen based on reported blood concentrations after an exchange transfusion procedure. RESULTS Thirty-minute exposure to MEHP increased the atrioventricular node (147 versus 107 ms) and ventricular (117 versus 77.5 ms) effective refractory periods, compared with controls. Optical mapping revealed prolonged action potential duration at slower pacing cycle lengths, akin to reverse use dependence. The plateau phase of the action potential duration restitution curve steepened and became monophasic in MEHP-exposed hearts (0.18 versus 0.06 slope). Action potential duration lengthening occurred during late-phase repolarization resulting in triangulation (70.3 versus 56.6 ms). MEHP exposure also slowed epicardial conduction velocity (35 versus 60 cm/s), which may be partly explained by inhibition of Nav1.5 (874 and 231 µmol/L half-maximal inhibitory concentration, fast and late sodium current). CONCLUSIONS This study highlights the impact of acute MEHP exposure, using a clinically relevant dose, on cardiac electrophysiology in the intact heart. Heightened clinical exposure to plasticized medical products may have cardiac safety implications-given that action potential triangulation and electrical restitution modifications are a risk factor for early after depolarizations and cardiac arrhythmias.
Collapse
Affiliation(s)
- Rafael Jaimes
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC.,Children's National Heart Institute (R.J., B.S., L.S., N.G.P.), Children's National Health System, Washington DC
| | - Damon McCullough
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC
| | - Bryan Siegel
- Children's National Heart Institute (R.J., B.S., L.S., N.G.P.), Children's National Health System, Washington DC
| | - Luther Swift
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC.,Children's National Heart Institute (R.J., B.S., L.S., N.G.P.), Children's National Health System, Washington DC
| | - Daniel McInerney
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC
| | - James Hiebert
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC
| | - Erick A Perez-Alday
- Knight Cardiovascular Institute, Oregon Health and Science University, Portland (E.A.P.-A., L.G.T.)
| | - Beatriz Trenor
- Ci2B-Universitat Politècnica de València, Spain (B.T., F.J.S.R.)
| | | | - Javier Saiz
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC
| | - Larisa G Tereshchenko
- Knight Cardiovascular Institute, Oregon Health and Science University, Portland (E.A.P.-A., L.G.T.)
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation (R.J., D. McCullough, L.S., D. McInerney, J.H., N.G.P.), Children's National Health System, Washington DC.,Children's National Heart Institute (R.J., B.S., L.S., N.G.P.), Children's National Health System, Washington DC.,Departments of Pediatrics and Pharmacology and Physiology, School of Medicine and Health Sciences: George Washington University, Washington DC (N.G.P.)
| |
Collapse
|
30
|
Ramadan M, Sherman M, Jaimes R, Chaluvadi A, Swift L, Posnack NG. Disruption of neonatal cardiomyocyte physiology following exposure to bisphenol-a. Sci Rep 2018; 8:7356. [PMID: 29743542 PMCID: PMC5943481 DOI: 10.1038/s41598-018-25719-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 04/27/2018] [Indexed: 12/21/2022] Open
Abstract
Bisphenol chemicals are commonly used in the manufacturing of polycarbonate plastics, polyvinyl chloride plastics, resins, and thermal printing applications. Humans are inadvertently exposed to bisphenols through contact with consumer products and/or medical devices. Recent reports have shown a link between bisphenol-a (BPA) exposure and adverse cardiovascular outcomes; although these studies have been limited to adult subjects and models. Since cardiac physiology differs significantly between the developing and adult heart, we aimed to assess the impact of BPA exposure on cardiac function, using a neonatal cardiomyocyte model. Neonatal rat ventricular myocytes were monitored to assess cell viability, spontaneous beating rate, beat rate variability, and calcium-handling parameters in the presence of control or bisphenol-supplemented media. A range of doses were tested to mimic environmental exposure (10-9-10-8M), maximum clinical exposure (10-5M), and supraphysiological exposure levels (10-4M). Acute BPA exposure altered cardiomyocyte functionality, resulting in a slowed spontaneous beating rate and increased beat rate variability. BPA exposure also impaired intracellular calcium handling, resulting in diminished calcium transient amplitudes, prolonged calcium transient upstroke and duration time. Alterations in calcium handling also increased the propensity for alternans and skipped beats. Notably, the effect of BPA-treatment on calcium handling was partially reversible. Our data suggest that acute BPA exposure could precipitate secondary adverse effects on contractile performance and/or electrical alternans, both of which are dependent on intracellular calcium homeostasis.
Collapse
Affiliation(s)
- Manelle Ramadan
- Sheikh Zayed Institute for Pediatric and Surgical Innovation, Children's National Health System, Washington, USA
- Children's National Heart Institute, Children's National Health System, Washington, USA
| | - Meredith Sherman
- Sheikh Zayed Institute for Pediatric and Surgical Innovation, Children's National Health System, Washington, USA
| | - Rafael Jaimes
- Sheikh Zayed Institute for Pediatric and Surgical Innovation, Children's National Health System, Washington, USA
- Children's National Heart Institute, Children's National Health System, Washington, USA
| | - Ashika Chaluvadi
- Sheikh Zayed Institute for Pediatric and Surgical Innovation, Children's National Health System, Washington, USA
| | - Luther Swift
- Sheikh Zayed Institute for Pediatric and Surgical Innovation, Children's National Health System, Washington, USA
- Children's National Heart Institute, Children's National Health System, Washington, USA
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric and Surgical Innovation, Children's National Health System, Washington, USA.
- Children's National Heart Institute, Children's National Health System, Washington, USA.
- Department of Pediatrics, Department of Pharmacology & Physiology, School of Medicine and Health Sciences, George Washington University, Washington, USA.
| |
Collapse
|
31
|
Jaimes R, Swiercz A, Sherman M, Muselimyan N, Marvar PJ, Posnack NG. Plastics and cardiovascular health: phthalates may disrupt heart rate variability and cardiovascular reactivity. Am J Physiol Heart Circ Physiol 2017; 313:H1044-H1053. [PMID: 28842438 PMCID: PMC5792203 DOI: 10.1152/ajpheart.00364.2017] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/17/2017] [Accepted: 08/17/2017] [Indexed: 12/11/2022]
Abstract
Plastics have revolutionized medical device technology, transformed hematological care, and facilitated modern cardiology procedures. Despite these advances, studies have shown that phthalate chemicals migrate out of plastic products and that these chemicals are bioactive. Recent epidemiological and research studies have suggested that phthalate exposure adversely affects cardiovascular function. Our objective was to assess the safety and biocompatibility of phthalate chemicals and resolve the impact on cardiovascular and autonomic physiology. Adult mice were implanted with radiofrequency transmitters to monitor heart rate variability, blood pressure, and autonomic regulation in response to di-2-ethylhexyl-phthalate (DEHP) exposure. DEHP-treated animals displayed a decrease in heart rate variability (-17% SD of normal beat-to-beat intervals and -36% high-frequency power) and an exaggerated mean arterial pressure response to ganglionic blockade (31.5% via chlorisondamine). In response to a conditioned stressor, DEHP-treated animals displayed enhanced cardiovascular reactivity (-56% SD major axis Poincarè plot) and prolonged blood pressure recovery. Alterations in cardiac gene expression of endothelin-1, angiotensin-converting enzyme, and nitric oxide synthase may partly explain these cardiovascular alterations. This is the first study to show an association between phthalate chemicals that are used in medical devices with alterations in autonomic regulation, heart rate variability, and cardiovascular reactivity. Because changes in autonomic balance often precede clinical manifestations of hypertension, atherosclerosis, and conduction abnormalities, future studies are warranted to assess the downstream impact of plastic chemical exposure on end-organ function in sensitive patient populations. This study also highlights the importance of adopting safer biomaterials, chemicals, and/or surface coatings for use in medical devices.NEW & NOTEWORTHY Phthalates are widely used in the manufacturing of consumer and medical products. In the present study, di-2-ethylhexyl-phthalate exposure was associated with alterations in heart rate variability and cardiovascular reactivity. This highlights the importance of investigating the impact of phthalates on health and identifying suitable alternatives for medical device manufacturing.
Collapse
Affiliation(s)
- Rafael Jaimes
- 1Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, District of Columbia; ,2Children’s National Heart Institute, Children’s National Health System, Washington, District of Columbia; and
| | - Adam Swiercz
- 3Department of Pharmacology and Physiology, George Washington University, Washington, District of Columbia
| | - Meredith Sherman
- 1Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Health System, Washington, District of Columbia;
| | - Narine Muselimyan
- 3Department of Pharmacology and Physiology, George Washington University, Washington, District of Columbia
| | - Paul J. Marvar
- 3Department of Pharmacology and Physiology, George Washington University, Washington, District of Columbia
| | - Nikki Gillum Posnack
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, District of Columbia; .,Children's National Heart Institute, Children's National Health System, Washington, District of Columbia; and.,Department of Pharmacology and Physiology, George Washington University, Washington, District of Columbia
| |
Collapse
|
32
|
Abstract
The ubiquitous nature of plastics has raised concerns pertaining to continuous exposure to plastic polymers and human health risks. Of particular concern is the use of endocrine-disrupting chemicals in plastic production, including di(2-ethylhexyl)phthalate (DEHP) and bisphenol A (BPA). Widespread and continuous exposure to DEHP and BPA occurs through dietary intake, inhalation, dermal and intravenous exposure via consumer products and medical devices. This article reviews the literature examining the relationship between DEHP and BPA exposure and cardiac toxicity. In vitro and in vivo experimental reports are outlined, as well as epidemiological studies which examine the association between these chemicals and cardiovascular outcomes. Gaps in our current knowledge are also discussed, along with future investigative endeavors that may help resolve whether DEHP and/or BPA exposure has a negative impact on cardiovascular physiology.
Collapse
Affiliation(s)
- Nikki Gillum Posnack
- Pharmacology and Physiology Department, The George Washington University School of Medicine and Health Sciences, 2300 Eye Street NW, Washington, DC, 20052, USA,
| |
Collapse
|
33
|
Posnack NG, Brooks D, Chandra A, Jaimes R, Sarvazyan N, Kay M. Physiological response of cardiac tissue to bisphenol A: alterations in ventricular pressure and contractility. Am J Physiol Heart Circ Physiol 2015; 309:H267-75. [PMID: 25980024 DOI: 10.1152/ajpheart.00272.2015] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 05/14/2015] [Indexed: 11/22/2022]
Abstract
Biomonitoring studies have indicated that humans are routinely exposed to bisphenol A (BPA), a chemical that is commonly used in the production of polycarbonate plastics and epoxy resins. Epidemiological studies have shown that BPA exposure in humans is associated with cardiovascular disease; however, the direct effects of BPA on cardiac physiology are largely unknown. Previously, we have shown that BPA exposure slows atrioventricular electrical conduction, decreases epicardial conduction velocity, and prolongs action potential duration in excised rat hearts. In the present study, we tested if BPA exposure also adversely affects cardiac contractile performance. We examined the impact of BPA exposure level, sex, and pacing rate on cardiac contractile function in excised rat hearts. Hearts were retrogradely perfused at constant pressure and exposed to 10(-9)-10(-4) M BPA. Left ventricular developed pressure and contractility were measured during sinus rhythm and during pacing (5, 6.5, and 9 Hz). Ca(2+) transients were imaged from whole hearts and from neonatal rat cardiomyocyte layers. During sinus rhythm in female hearts, BPA exposure decreased left ventricular developed pressure and inotropy in a dose-dependent manner. The reduced contractile performance was exacerbated at higher pacing rates. BPA-induced effects on contractile performance were also observed in male hearts, albeit to a lesser extent. Exposure to BPA altered Ca(2+) handling within whole hearts (reduced diastolic and systolic Ca(2+) transient potentiation) and neonatal cardiomyocytes (reduced Ca(2+) transient amplitude and prolonged Ca(2+) transient release time). In conclusion, BPA exposure significantly impaired cardiac performance in a dose-dependent manner, having a major negative impact upon electrical conduction, intracellular Ca(2+) handing, and ventricular contractility.
Collapse
Affiliation(s)
- Nikki Gillum Posnack
- Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, District of Columbia; and
| | - Daina Brooks
- Department of Biomedical Engineering, School of Engineering and Applied Sciences, The George Washington University, Washington, District of Columbia
| | - Akhil Chandra
- Department of Biomedical Engineering, School of Engineering and Applied Sciences, The George Washington University, Washington, District of Columbia
| | - Rafael Jaimes
- Department of Biomedical Engineering, School of Engineering and Applied Sciences, The George Washington University, Washington, District of Columbia
| | - Narine Sarvazyan
- Department of Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, District of Columbia; and
| | - Matthew Kay
- Department of Biomedical Engineering, School of Engineering and Applied Sciences, The George Washington University, Washington, District of Columbia
| |
Collapse
|
34
|
Wengrowski AM, Wang X, Tapa S, Posnack NG, Mendelowitz D, Kay MW. Optogenetic release of norepinephrine from cardiac sympathetic neurons alters mechanical and electrical function. Cardiovasc Res 2014; 105:143-50. [PMID: 25514932 DOI: 10.1093/cvr/cvu258] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AIMS Release of norepinephrine (NE) from sympathetic neurons enhances heart rate (HR) and developed force through activation of β-adrenergic receptors, and this sympathoexcitation is a key risk for the generation of cardiac arrhythmias. Studies of β-adrenergic modulation of cardiac function typically involve the administration of exogenous β-adrenergic receptor agonists to directly elicit global β-adrenergic receptor activation by bypassing the involvement of sympathetic nerve terminals. In this work, we use a novel method to activate sympathetic fibres within the myocardium of Langendorff-perfused hearts while measuring changes in electrical and mechanical function. METHODS AND RESULTS The light-activated optogenetic protein channelrhodopsin-2 (ChR2) was expressed in murine catecholaminergic sympathetic neurons. Sympathetic fibres were then photoactivated to examine changes in contractile force, HR, and cardiac electrical activity. Incidence of arrhythmia was measured with and without exposure to photoactivation of sympathetic fibres, and hearts were optically mapped to detect changes in action potential durations and conduction velocities. Results demonstrate facilitation of both developed force and HR after photostimulated release of NE, with increases in contractile force and HR of 34.5 ± 5.5 and 25.0 ± 9.3%, respectively. Photostimulation of sympathetic fibres also made hearts more susceptible to arrhythmia, with greater incidence and severity. In addition, optically mapped action potentials displayed a small but significant shortening of the plateau phase (-5.5 ± 1.0 ms) after photostimulation. CONCLUSION This study characterizes a powerful and clinically relevant new model for studies of cardiac arrhythmias generated by increasing the activity of sympathetic nerve terminals and the resulting activation of myocyte β-adrenergic receptors.
Collapse
Affiliation(s)
- Anastasia M Wengrowski
- Department of Biomedical Engineering, The George Washington University, Phillips Hall, Room 607, 801 22nd Street NW, Washington, DC 20052, USA
| | - Xin Wang
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC, USA
| | - Srinivas Tapa
- Department of Biomedical Engineering, The George Washington University, Phillips Hall, Room 607, 801 22nd Street NW, Washington, DC 20052, USA
| | - Nikki Gillum Posnack
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC, USA
| | - David Mendelowitz
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC, USA
| | - Matthew W Kay
- Department of Biomedical Engineering, The George Washington University, Phillips Hall, Room 607, 801 22nd Street NW, Washington, DC 20052, USA Department of Pharmacology and Physiology, The George Washington University, Washington, DC, USA
| |
Collapse
|
35
|
Posnack NG, Jaimes R, Asfour H, Swift LM, Wengrowski AM, Sarvazyan N, Kay MW. Bisphenol A exposure and cardiac electrical conduction in excised rat hearts. Environ Health Perspect 2014; 122:384-90. [PMID: 24487307 PMCID: PMC3984226 DOI: 10.1289/ehp.1206157] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 01/29/2014] [Indexed: 05/20/2023]
Abstract
BACKGROUND Bisphenol A (BPA) is used to produce polycarbonate plastics and epoxy resins that are widely used in everyday products, such as food and beverage containers, toys, and medical devices. Human biomonitoring studies have suggested that a large proportion of the population may be exposed to BPA. Recent epidemiological studies have reported correlations between increased urinary BPA concentrations and cardiovascular disease, yet the direct effects of BPA on the heart are unknown. OBJECTIVES The goal of our study was to measure the effect of BPA (0.1-100 μM) on cardiac impulse propagation ex vivo using excised whole hearts from adult female rats. METHODS We measured atrial and ventricular activation times during sinus and paced rhythms using epicardial electrodes and optical mapping of transmembrane potential in excised rat hearts exposed to BPA via perfusate media. Atrioventricular activation intervals and epicardial conduction velocities were computed using recorded activation times. RESULTS Cardiac BPA exposure resulted in prolonged PR segment and decreased epicardial conduction velocity (0.1-100 μM BPA), prolonged action potential duration (1-100 μM BPA), and delayed atrioventricular conduction (10-100 μM BPA). These effects were observed after acute exposure (≤ 15 min), underscoring the potential detrimental effects of continuous BPA exposure. The highest BPA concentration used (100 μM) resulted in prolonged QRS intervals and dropped ventricular beats, and eventually resulted in complete heart block. CONCLUSIONS Our results show that acute BPA exposure slowed electrical conduction in excised hearts from female rats. These findings emphasize the importance of examining BPA's effect on heart electrophysiology and determining whether chronic in vivo exposure can cause or exacerbate conduction abnormalities in patients with preexisting heart conditions and in other high-risk populations.
Collapse
|
36
|
Posnack NG, Jaimes R, Asfour H, Swift LM, Wengrowski AM, Sarvazyan N, Kay MW. Bisphenol A (BPA) exposure perturbs cardiac electrical conduction in excised rat hearts. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.706.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Rafael Jaimes
- Electrical & Computer EngineeringThe George Washington UniversityWashingtonDC
| | - Huda Asfour
- Electrical & Computer EngineeringThe George Washington UniversityWashingtonDC
| | - Luther M Swift
- Pharmacology & PhysiologyThe George Washington UniversityWashingtonDC
| | | | - Narine Sarvazyan
- Pharmacology & PhysiologyThe George Washington UniversityWashingtonDC
| | - Matthew W Kay
- Pharmacology & PhysiologyThe George Washington UniversityWashingtonDC
- Electrical & Computer EngineeringThe George Washington UniversityWashingtonDC
| |
Collapse
|
37
|
Posnack NG, Swift LM, Kay MW, Lee NH, Sarvazyan N. Phthalate exposure changes the metabolic profile of cardiac muscle cells. Environ Health Perspect 2012; 120:1243-51. [PMID: 22672789 PMCID: PMC3440133 DOI: 10.1289/ehp.1205056] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 06/06/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND Phthalates are common plasticizers present in medical-grade plastics and other everyday products. They can also act as endocrine-disrupting chemicals and have been linked to the rise in metabolic disorders. However, the effect of phthalates on cardiac metabolism remains largely unknown. OBJECTIVES We examined the effect of di(2-ethylhexyl)phthalate (DEHP) on the metabolic profile of cardiomyocytes because alterations in metabolic processes can lead to cell dysfunction. METHODS Neonatal rat cardiomyocytes were treated with DEHP at a concentration and duration comparable to clinical exposure (50-100 μg/mL, 72 hr). We assessed the effect of DEHP on gene expression using microarray analysis. Physiological responses were examined via fatty acid utilization, oxygen consumption, mitochondrial mass, and Western blot analysis. RESULTS Exposure to DEHP led to up-regulation of genes associated with fatty acid transport, esterification, mitochondrial import, and β-oxidation. The functional outcome was an increase in myocyte fatty acid-substrate utilization, oxygen consumption, mitochondrial mass, PPARα (peroxisome proliferator-activated receptor α) protein expression, and extracellular acidosis. Treatment with a PPARα agonist (Wy-14643) only partially mimicked the effects observed in DEHP-treated cells. CONCLUSIONS Data suggest that DEHP exposure results in metabolic remodeling of cardiomyocytes, whereby cardiac cells increase their dependence on fatty acids for energy production. This fuel switch may be regulated at both the gene expression and posttranscription levels. Our findings have important clinical implications because chronic dependence on fatty acids is associated with an accumulation in lipid intermediates, lactate, protons, and reactive oxygen species. This dependence can sensitize the heart to ischemic injury and ventricular dysfunction.
Collapse
Affiliation(s)
- Nikki Gillum Posnack
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC, USA.
| | | | | | | | | |
Collapse
|
38
|
Abstract
Repair of damaged myocardium with pluripotent stem cell derived cardiomyocytes is becoming increasingly more feasible. Developments in stem cell research emphasize the need to address the foreseeable problem of immune rejection following transplantation. Pluripotent stem cell (PSC) derived cardiomyocytes have unique immune characteristics, some of which are not advantageous for transplantation. Here we review the possible mechanisms of PSC-derived cardiomyocytes rejection, summarize the current knowledge pertaining to immunogenicity of such cells and describe the existing controversies. Myocardial graft rejection can be reduced by modifying PSCs prior to their differentiation into cardiomyocytes. Overall, this approach facilitates the development of universal donor stem cells suitable for the regeneration of many different tissue types.
Collapse
Affiliation(s)
- Zaruhi Karabekian
- Pharmacology and Physiology Department, The George Washington University, 2300 Eye Street, Washington, DC 20037, USA
| | | | | |
Collapse
|
39
|
Posnack NG, Lee NH, Brown R, Sarvazyan N. Gene expression profiling of DEHP-treated cardiomyocytes reveals potential causes of phthalate arrhythmogenicity. Toxicology 2010; 279:54-64. [PMID: 20920545 DOI: 10.1016/j.tox.2010.09.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 09/14/2010] [Accepted: 09/15/2010] [Indexed: 01/12/2023]
Abstract
BACKGROUND Di-(2-ethylhexyl)-phthalate (DEHP) is a widely used plasticizer that imparts flexibility to polyvinyl chloride. We have recently reported that clinically relevant concentrations of DEHP can affect electrical coupling between cardiac myocytes causing significant rhythm disturbances. The underlying causes for this effect are currently unknown. OBJECTIVES To use data on global mRNA expression as a tool to reveal possible pathways leading to arrhythmogenic effects of DEHP. METHODS Rat neonatal cardiomyocytes were treated with 50 μg/mL DEHP for 72 h. Extracted RNA samples were hybridized onto Affymetrix Rat Gene 1.0 ST arrays. The mRNA expression of a subset of genes was validated by qRT-PCR. In a second set of experiments, cells were treated in a concentration dependent manner to identify genes affected by low DEHP concentrations. RESULTS DEHP exposure is associated with global changes in mRNA expression, with differentially expressed genes overrepresented in 47 Gene Ontology categories. Modified expression was detected for genes associated with cell electrical activity, calcium handling, adhesion and microtubular transport. For a number of key proteins, including kinesin, TGFβ2, α-tubulin, and α1 & β1 integrins, changes in mRNA levels were confirmed on the level of the protein expression. A number of genes associated with cell adhesion and electrical activity were identified as early DEHP targets as they were affected by concentrations as low as 1 μg/mL. CONCLUSIONS Exposure of neonatal rat cardiomyocytes to clinically relevant DEHP concentrations leads to global changes in mRNA expression. These changes help to explain the arrhythmogenic effects of phthalates on these cells.
Collapse
Affiliation(s)
- Nikki Gillum Posnack
- The Pharmacology & Physiology Department, The George Washington University, 2300 Eye Street, Washington, DC 20037, USA
| | | | | | | |
Collapse
|
40
|
Asfour H, Soller W, Posnack NG, Pollard AE, Kay MW. Low frequency impedance spectroscopy of cell monolayers using the four-electrode method. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/224/1/012085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|