1
|
Establishment of an integrated automated embryonic manipulation system for producing genetically modified mice. Sci Rep 2021; 11:11770. [PMID: 34083640 PMCID: PMC8175685 DOI: 10.1038/s41598-021-91148-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 05/18/2021] [Indexed: 11/09/2022] Open
Abstract
Genetically modified mice are commonly used in biologic, medical, and drug discovery research, but conventional microinjection methods used for genetic modification require extensive training and practical experience. Here we present a fully automated system for microinjection into the pronucleus to facilitate genetic modification. We first developed software that automatically controls the microinjection system hardware. The software permits automatic rotation of the zygote to move the pronucleus to the injection pipette insertion position. We also developed software that recognizes the pronucleus in 3-dimensional coordinates so that the injection pipette can be automatically inserted into the pronucleus, and achieved a 94% insertion rate by linking the 2 pieces of software. Next, we determined the optimal solution injection conditions (30 hPa, 0.8-2.0 s) by examining the survival rate of injected zygotes. Finally, we produced transgenic (traditional DNA injection and piggyBac Transposon system) and knock-in (genomic editing) mice using our newly developed Integrated Automated Embryo Manipulation System (IAEMS). We propose that the IAEMS will simplify highly reproducible pronuclear stage zygote microinjection procedures.
Collapse
|
2
|
Leukemia Stem Cell Drug Discovery. Methods Mol Biol 2021. [PMID: 33165841 DOI: 10.1007/978-1-0716-0810-4_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The relative survival of cancer patients, when considering the tumoral stage at diagnosis, has not changed significantly in the last three decades, in spite of our increasingly detailed knowledge of the molecular alterations occurring in human tumors. In parallel, despite a growing number of clinical trials being conducted, the absolute number of drugs that are effective in humans is declining, and many new drugs move into the market without having enough evidence of their benefit on survival or quality of life. In part, this failure is due to the discordance between the results from preclinical and clinical trial phases, therefore leading to a high percentage of apparently promising lead compounds being abandoned in the transfer to the clinic. This discordance is caused, to a large degree, by the use of inappropriate animal models in the first stages of drug development. In this chapter, we discuss how the development of cancer therapies needs to be redesigned in order to achieve cancer cure, and how this redesign must involve the generation of better animal models, based on the tenets of the cancer stem cell theory, and capable of recapitulating all the aspects of human cancer. The use of such improved models should increase the likelihood of success in drug development, reducing the number of agents that go into trial, and the amount of patients undergoing useless trials.
Collapse
|
3
|
Frick A, Suzuki O, Butz N, Chan E, Wiltshire T. In vitro and in vivo mouse models for pharmacogenetic studies. Methods Mol Biol 2014; 1015:263-78. [PMID: 23824862 DOI: 10.1007/978-1-62703-435-7_17] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The identification of causative genes underlying biomedically relevant phenotypes, particularly complex multigenic traits, is of vital interest to modern medicine. Using genome-wide association analysis, many studies have successfully identified thousands of loci (called quantitative trait loci or QTL), some of these associating with drug response phenotypes. However, the determination and validation of putative genes has been much more challenging. The actions of drugs, both efficacious and deleterious, are complex phenotypes that are controlled or influenced in part by genetic mechanisms.Investigation for genetic correlates of complex traits and pharmacogenetic traits is often difficult to perform in human studies due to cost, availability of relevant sample population, and limited ability to control for environmental effects. These challenges can be circumvented with the use of mouse models for pharmacogenetic studies. In addition, the mouse can be treated at sub- and supratherapeutic doses and subjected to invasive procedures, which can facilitate measures of drug response phenotypes, making identification of pharmacogenetically relevant genes more feasible. The availability of multiple mouse genetic and phenotypic resources is an additional benefit to using the mouse for pharmacogenetic studies.Here, we describe the contribution of animal models, specifically the mouse, towards the field of pharmacogenetics. In this chapter, we describe different mouse models, including the knockout mouse, recombinant mouse inbred strains, in vitro mouse cell-based assays, as well as novel experimental approaches like the Collaborative Cross recombinant mouse inbred panel, which can be applied to preclinical pharmacogenetics research. These approaches can be used to assess drug response phenotypes that are difficult to model in humans, thereby facilitating drug discovery, development, and application.
Collapse
Affiliation(s)
- Amber Frick
- Division of Pharmacotherapy and Experimental Therapeutics, Institute for Pharmacogenomics and Individualized Therapy, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | | | | | | |
Collapse
|
4
|
Yoshizato K, Tateno C. A mouse with humanized liver as an animal model for predicting drug effects and for studying hepatic viral infection: where to next? Expert Opin Drug Metab Toxicol 2013; 9:1419-35. [DOI: 10.1517/17425255.2013.826649] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
5
|
Simkó J, Szabó Z, Barta K, Ujvárosi D, Nánási P, Lőrincz I. [Molecular and genetic background of sudden cardiac death]. Orv Hetil 2012; 153:1967-83. [PMID: 23220363 DOI: 10.1556/oh.2012.29498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Despite recent findings on the functional, structural and genetic background of sudden cardiac death, the incidence is still relatively high in the entire population. A thorough knowledge on susceptibility, as well as pathophysiology behind the development of malignant arrhythmias will help us to identify individuals at risk and prevent sudden cardiac death. This article presents a review of the current literature on the role of altered intracellular Ca2+ handling, acute myocardial ischaemia, cardiac autonomic innervation, renin-angiotensin-aldosterone system, monogenic and complex heritability in the pathogenesis of sudden cardiac death.
Collapse
Affiliation(s)
- József Simkó
- Miskolci Semmelweis Ignác Egészségügyi Központ és Egyetemi Oktatókórház Nonprofit Kft. Belgyógyászati Intézet, Kardiológiai Osztály Miskolc.
| | | | | | | | | | | |
Collapse
|
6
|
Jiang XL, Gonzalez FJ, Yu AM. Drug-metabolizing enzyme, transporter, and nuclear receptor genetically modified mouse models. Drug Metab Rev 2010; 43:27-40. [PMID: 20854191 DOI: 10.3109/03602532.2010.512294] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Determining the in vivo significance of a specific enzyme, transporter, or xenobiotic receptor in drug metabolism and pharmacokinetics may be hampered by gene multiplicity and complexity, levels of expression, and interaction between various components involved. The development of knockout (loss-of-function) and transgenic (gain-of-function) mouse models opens the door to the improved understanding of gene function in a whole-body system. There is also growing interest in the development of humanized mice to overcome species differences in drug metabolism and disposition. This review, therefore, aims to summarize and discuss some successful examples of drug-metabolizing enzyme, transporter, and nuclear-receptor genetically modified mouse models. These genetically modified mouse models have been proven as invaluable models for understanding in vivo function of drug-metabolizing enzymes, transporters, and xenobiotic receptors in drug metabolism and transport, as well as predicting potential drug-drug interaction and toxicity in humans. Nevertheless, concerns remain about interpretation of data obtained from such genetically modified mouse models, in which the expression of related genes is altered significantly.
Collapse
Affiliation(s)
- Xi-Ling Jiang
- Department of Pharmaceutical Sciences, University at Buffalo, The State University of New York, USA
| | | | | |
Collapse
|
7
|
Heydendael W, Jacobson L. Glucocorticoid status affects antidepressant regulation of locus coeruleus tyrosine hydroxylase and dorsal raphé tryptophan hydroxylase gene expression. Brain Res 2009; 1288:69-78. [PMID: 19577549 DOI: 10.1016/j.brainres.2009.06.082] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Revised: 05/10/2009] [Accepted: 06/25/2009] [Indexed: 10/20/2022]
Abstract
Brainstem monoaminergic nuclei express glucocorticoid receptors (GR), and glucocorticoids have been shown to inhibit expression of enzymes involved in monoamine synthesis. Monoamine deficits have been implicated in depression pathology. However, it is unknown if antidepressants regulate brainstem GR, and if glucocorticoids might influence antidepressant effects on monoamine-synthesizing enzymes. Our lab has found opposing effects of the monoamine oxidase inhibitor phenelzine and the tricyclic antidepressant imipramine on HPA activity and forebrain GR gene expression. We therefore hypothesized that phenelzine and imipramine would also affect brainstem GR gene expression differentially, and that antidepressant-induced changes in GR expression would correlate with effects on monoamine-synthesizing enzyme expression. Using in situ hybridization, we measured effects of chronic antidepressant treatment on brainstem GR, locus coeruleus and ventral tegmental area (VTA) tyrosine hydroxylase (TH), and dorsal raphé tryptophan hydroxylase (TPH2) gene expression in male C57BL/6 mice that were adrenalectomized and replaced with defined levels of corticosterone. GR expression was decreased by phenelzine in the locus coeruleus and decreased by imipramine in the dorsal raphé. Phenelzine increased locus coeruleus TH and imipramine increased dorsal raphé TPH2 gene expression in a glucocorticoid-dependent manner, suggesting that increases in these enzymes were due to relief of inhibitory glucocorticoid signaling. We did not find antidepressant effects on GR or TH expression in the VTA or on mineralocorticoid receptor (MR) expression in any of the nuclei examined. Our findings represent a potential mechanism through which antidepressants and glucocorticoids could alter both HPA activity and mood via effects on brainstem GR, norepinephrine, and serotonin.
Collapse
Affiliation(s)
- Willem Heydendael
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Mail Code 136, Albany, NY 12208, USA
| | | |
Collapse
|
8
|
Abstract
Genetically modified animals represent a resource of immense potential for cancer research. Classically, genetic modifications in mice were obtained through selected breeding experiments or treatments with powerful carcinogens capable of inducing random mutagenesis. A new era began in the early 1980s when genetic modifications by inserting foreign DNA genes into the cells of an animal allowed for the development of transgenic mice. Since that moment, genetic modifications have been able to be made in a predetermined way. Gene targeting emerged later as a method of in vivo mutagenesis whereby the sequence of a predetermined gene is selectively modified within an intact cell. In this review we focus on how genetically modified mice can be created to study tumour development, and how these models have contributed to an understanding of the genetic alterations involved in human cancer. We also discuss the strengths and weaknesses of the different mouse models for identifying cancer genes, and understanding the consequences of their alterations in order to obtain the maximum benefit for cancer patients.
Collapse
|
9
|
Tang QO, Tran GT, Gamie Z, Graham S, Tsialogiannis E, Tsiridis E, Linder T, Tsiridis E. Statins: under investigation for increasing bone mineral density and augmenting fracture healing. Expert Opin Investig Drugs 2008; 17:1435-63. [DOI: 10.1517/13543784.17.10.1435] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
10
|
Abstract
Sudden cardiac death (SCD) is among the most common causes of death in developed countries throughout the world. Despite decreased overall cardiac mortality, SCD rates appear to be increasing in concert with escalating global prevalence of coronary disease and heart failure, the two major conditions predisposing to SCD. This unfavorable trend is a consequence of our inability to identify those who will die suddenly from lethal ventricular arrhythmias and to develop effective therapies for all populations at risk. The known risk factors for SCD lack the predictive power needed to generate preventive strategies for the large number of fatal arrhythmic events that occur among lower-risk subsets of the population. Even among recognized high-risk subsets, prediction of SCD remains challenging. With the exception of the implantable cardioverter defibrillator (ICD) there are few effective strategies for the prevention and treatment of SCD. This article discusses the prospect of genomic science as an approach to the identification of patients at high-risk for SCD. While the final common pathway for SCD is malignant ventricular arrhythmias, there are many potential contributors, pathways, and mechanisms by which common genetic variants (polymorphisms) could affect initiation and propagation of life-threatening cardiac arrhythmias. Recent advances in genomic medicine now provide us with novel approaches to both identify candidate genes/pathways and relatively common polymorphisms which may predispose patients to increased risk for SCD. Improved understanding of the relationship between common polymorphisms and SCD will not only improve risk stratification such that ICDs can be targeted to those patients most likely to benefit from them but also provide new insight into the pathophysiology of SCD.
Collapse
|
11
|
Hou J, Shan Q, Wang T, Gomes AS, Yan Q, Paul DL, Bleich M, Goodenough DA. Transgenic RNAi depletion of claudin-16 and the renal handling of magnesium. J Biol Chem 2007; 282:17114-22. [PMID: 17442678 DOI: 10.1074/jbc.m700632200] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Tight junctions play a key role in mediating paracellular ion reabsorption in the kidney. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a human disorder caused by mutations in the tight junction protein claudin-16. However, the molecular mechanisms underlining the renal handling of magnesium and its dysfunction causing FHHNC are unknown. Here we show that claudin-16 plays a key role in maintaining the paracellular cation selectivity of the thick ascending limbs of the nephron. Using RNA interference, we have generated claudin-16-deficient mouse models. Claudin-16 knock-down (KD) mice exhibit chronic renal wasting of magnesium and calcium and develop renal nephrocalcinosis. Our data suggest that claudin-16 forms a non-selective paracellular cation channel, rather than a selective Mg(2+)/Ca(2+) channel as previously proposed. Our study highlights the pivotal importance of the tight junction in renal control of ion homeostasis and provides answer to the pathogenesis of FHHNC. We anticipate our study to be a starting point for more sophisticated in vivo analysis of tight junction proteins in renal functions. Furthermore, tight junction proteins could be major targets of drug development for electrolyte disorders.
Collapse
Affiliation(s)
- Jianghui Hou
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
In the last decade, site-specific recombinases (SSRs), such as Cre and Flp, have emerged as indispensable tools for the precise in vivo manipulation of the mouse genome. It is now feasible to control, in space and time, the onset of gene knockouts in almost any tissue of the mouse, thus greatly facilitating the creation of sophisticated animal models for human disease and drug development. This review describes the basic principles and current status of the SSR technology, with a focus on strategies for conditional somatic mutagenesis using the Cre/lox system and ligand-activated Cre recombinases. Practical hints for generating and analysing conditional mouse mutants will be given and exciting novel applications of the SSR technology will be discussed, such as cell fate mapping and the combined use of Cre, Flp and other biotechnological tools. It will be shown how genetic manipulation of the mouse by site-specific recombination can provide new solutions to old problems in the analysis of human physiology and pathophysiology and how it can be employed for drug discovery and development.
Collapse
Affiliation(s)
- R Feil
- Interfakultäres Institut für Biochemie, Universität Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany.
| |
Collapse
|
13
|
|
14
|
Watanabe T, Schulz D, Morisseau C, Hammock BD. High-throughput pharmacokinetic method: cassette dosing in mice associated with minuscule serial bleedings and LC/MS/MS analysis. Anal Chim Acta 2006; 559:37-44. [PMID: 16636700 PMCID: PMC1447531 DOI: 10.1016/j.aca.2005.11.049] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A method for pharmacokinetic studies using cassette dosing associated with serial bleeding in mice is described. PK profiles of four soluble epoxide hydrolase inhibitors were determined following oral, subcutaneous or intraperitoneal administration individually or in cassette dosing. Parent analyses were performed on only 5 microL of whole blood from serial bleeds (up to 10 per animal), by LC/MS/MS. An accuracy (88-100%) and precision (<10% RSD) were observed, leading to reliable datum points for PK calculation. PK profiles, T(max), C(max) and half-life values after cassette dosing were similar to the individual PK results. This method dramatically increases speed of data collection while dramatically reducing cost and animal usage. The results presented here clearly indicate that this proposed method could be applicable to high-throughput PK studies.
Collapse
Affiliation(s)
- Takaho Watanabe
- Department of Entomology and UCD Cancer Center, University of California, One Shields Avenue, Davis, CA 95616, USA
| | | | | | | |
Collapse
|
15
|
Lillquist E, Sullivan CA. Legal regulation of the use of race in medical research. THE JOURNAL OF LAW, MEDICINE & ETHICS : A JOURNAL OF THE AMERICAN SOCIETY OF LAW, MEDICINE & ETHICS 2006; 34:535-51, 480. [PMID: 17144177 DOI: 10.1111/j.1748-720x.2006.00067.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In this article, we discuss current legal restrictions governing the use of race in medical research. In particular, we focus on whether the use of race in various types of research is presently permitted under federal law and the federal constitution. We also discuss whether federal restrictions on the use of race in research ought to be expanded, and whether federal policies that encourage the use of race ought to be abandoned.
Collapse
Affiliation(s)
- Erik Lillquist
- Institute of Law, Science and Technology at Seton Hall Law School, USA
| | | |
Collapse
|
16
|
Alisky JM, Chertkova EL, Iczkowski KA. Drug interactions and pharmacogenetic reactions are the basis for chloroquine and mefloquine-induced psychosis. Med Hypotheses 2006; 67:1090-4. [PMID: 16843615 DOI: 10.1016/j.mehy.2006.01.059] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Accepted: 01/25/2006] [Indexed: 11/23/2022]
Abstract
BACKGROUND Chloroquine and mefloquine used for prophylaxis and treatment of malaria sometimes causes severe mental status changes, through mechanisms that are poorly understood. PRESENTATION OF THE HYPOTHESIS Psychosis is caused by interactions with other drugs or by pharmacogenetic vulnerabilities that cause heightened responses to chloroquine or mefloquine alone, mediated through dopamine, acetylcholine, serotonin, P-glycoprotein, inhibited cortical activity, deranged calcium homeostasis, and impaired synaptogenesis. TESTING THE HYPOTHESIS Retrospective studies can identify all other drugs taken coincident with chloroquine or mefloquine psychosis. Various genes from patients could be cloned and compared to those from individuals who tolerated chloroquine and mefloquine, culminating with transgenic animal studies. Identification of candidate genes may be aided by pharmacogenomic analysis of single nucleotide polymorphism maps. Finally, prospective studies with cerebrospinal fluid analysis and PET scanning could help verify the hypothesis. IMPLICATIONS OF THE HYPOTHESIS If this hypothesis is correct, the incidence of chloroquine and mefloquine psychosis can be greatly reduced by avoiding interacting medications and by conducting genetic screening prior to initiating chloroquine and mefloquine. Validation of the hypothesis would also provide a paradigm to follow for avoiding neuropsychiatric side effects if antidepressants and neuroleptics are used to overcome chloroquine resistance, if new antimalarial drugs chemically related to chloroquine and mefloquine are developed and if chloroquine and mefloquine are used for non-malarial applications such as HIV and cancer.
Collapse
Affiliation(s)
- Joseph M Alisky
- Marshfield Clinic Research Foundation, 1000 Oak Avenue, Marshfield, WI 54449, USA
| | | | | |
Collapse
|
17
|
Abstract
Contents Transgenic animals are more widely used for various purposes. Applications of animal transgenesis may be divided into three major categories: (i) to obtain information on gene function and regulation as well as on human diseases, (ii) to obtain high value products (recombinant pharmaceutical proteins and xeno-organs for humans) to be used for human therapy, and (iii) to improve animal products for human consumption. All these applications are directly or not related to human health. Animal transgenesis started in 1980. Important improvement of the methods has been made and are still being achieved to reduce cost as well as killing of animals and to improve the relevance of the models. This includes gene transfer and design of reliable vectors for transgene expression. This review describes the state of the art of animal transgenesis from a technical point of view. It also reports some of the applications in the medical field based on the use of transgenic animal models. The advance in the generation of pigs to be used as the source of organs for patients and in the preparation of pharmaceutical proteins from milk and other possible biological fluids from transgenic animals is described. The projects in course aiming at improving animal production by transgenesis are also depicted. Some the specific biosafety and bioethical problems raised by the different applications of transgenesis, including consumption of transgenic animal products are discussed.
Collapse
Affiliation(s)
- L-M Houdebine
- Biologie du Développement et Reproduction, Institut National de la Recherche Agronomique, Jouy-en-Josas Cedex, France.
| |
Collapse
|
18
|
Roses AD, Burns DK, Chissoe S, Middleton L, St Jean P. Disease-specific target selection: a critical first step down the right road. Drug Discov Today 2005; 10:177-89. [PMID: 15708532 DOI: 10.1016/s1359-6446(04)03321-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Relevance of a drug target for a disease is often inferred with strong belief but fragile evidence. Here, a program for early identification of human disease-specific drug targets using high-throughput genetic associations is described. Large numbers of well-characterized patients (>1000) and matched controls are screened for genetic associations using several thousand (>7000) single nucleotide polymorphisms from more than 1500 genes. The genes were selected because they are members of target classes for which there are precedents for high-throughput chemical screening technology. This review summarizes the methods and intensive data analyses leading to target gene identification for type 2 diabetes mellitus, including the statistical permutation methodology used to correct for many variables.
Collapse
Affiliation(s)
- Allen D Roses
- GlaxoSmithKline R&D, Research Triangle Park, NC 27709, USA.
| | | | | | | | | |
Collapse
|
19
|
Benjamin IJ, Schneider MD. Learning from failure: congestive heart failure in the postgenomic age. J Clin Invest 2005; 115:495-9. [PMID: 15765130 PMCID: PMC1052014 DOI: 10.1172/jci24477] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The prognosis of heart failure is worse than that of most cancers, but new therapeutic interventions using stem and other cell-based therapies are succeeding in the fight against it, and old drugs, with new twists, are making a comeback. Genetically engineered animal models are driving insights into the molecular mechanisms that cause hearts to fail, accelerating drug discoveries, and inspiring cell-based therapeutic interventions for both acquired and inheritable cardiac diseases.
Collapse
Affiliation(s)
- Ivor J Benjamin
- Division of Cardiology, Department of Internal Medicine, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA.
| | | |
Collapse
|
20
|
Benjamin IJ, Schneider MD. Learning from failure: congestive heart failure in the postgenomic age. J Clin Invest 2005. [PMID: 15765130 DOI: 10.1172/jci200524477] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The prognosis of heart failure is worse than that of most cancers, but new therapeutic interventions using stem and other cell-based therapies are succeeding in the fight against it, and old drugs, with new twists, are making a comeback. Genetically engineered animal models are driving insights into the molecular mechanisms that cause hearts to fail, accelerating drug discoveries, and inspiring cell-based therapeutic interventions for both acquired and inheritable cardiac diseases.
Collapse
Affiliation(s)
- Ivor J Benjamin
- Division of Cardiology, Department of Internal Medicine, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA.
| | | |
Collapse
|
21
|
Shafaroudi MM, McBride M, Deighan C, Wokoma A, Macmillan J, Daly CJ, McGrath JC. Two "knockout" mouse models demonstrate that aortic vasodilatation is mediated via alpha2a-adrenoceptors located on the endothelium. J Pharmacol Exp Ther 2005; 314:804-10. [PMID: 15878998 DOI: 10.1124/jpet.105.085944] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
UK-14,304 [5-bromo-N-(4,5-dihydro-1H-imidazol-2-yl)-6-quinoxalinamine]-mediated vasodilator responses were studied on wire myograph-mounted mouse aorta to determine the cells involved, mechanisms of action, and subtypes of alpha(2)-adrenoceptors. In the presence of induced tone, UK-14,304 produced concentration-related vasodilatation that was abolished by rauwolscine, N(omega)-nitro-L-arginine methyl ester (L-NAME), or endothelium removal, indicating that endothelial alpha(2)-adrenoceptors can release nitric oxide. In the alpha(2A)-adrenoceptor knockout mouse and the D79N mouse, a functional knockout of the alpha(2A)-adrenoceptor, these relaxant effects of UK-14,304 were lost, indicating the involvement of the alpha(2A)-adrenoceptor. UK-14,304 could also contract aorta: a small contraction occurred at high concentrations, was enhanced by L-NAME, and was absent in the alpha(1D)-adrenoceptor knockout mouse, indicating activation of the alpha(1D)-adrenoceptor. There was no evidence for a contractile alpha(2)-adrenoceptor-mediated response. A fluorescent ligand, quinazoline piperazine bodipy, antagonized the relaxant action of UK-14,304. This compound could be visualized on aortic endothelial cells, and its binding could be prevented by rauwolscine, providing direct evidence for the presence of alpha(2)-adrenoceptors on the endothelium. Norepinephrine reduced tone in the alpha(1D)-adrenoceptor knockout and controls, an effect blocked by rauwolscine and L-NAME but not by prazosin. This suggests that norepinephrine activates endothelial alpha(2)-adrenoceptors. In conclusion, the endothelium of mouse aorta has an alpha(2A)-adrenoceptor that responds to norepinephrine; promotes the release of nitric oxide, causing smooth muscle relaxation; and that can be directly visualized. Knockout or genetic malfunction of this receptor should increase arterial stiffness, exacerbated by raised catecholamines, and contribute to heart failure.
Collapse
MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Brimonidine Tartrate
- Dose-Response Relationship, Drug
- Endothelial Cells/drug effects
- Endothelial Cells/metabolism
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Enzyme Inhibitors/pharmacology
- Fluorescent Dyes
- Image Processing, Computer-Assisted
- In Vitro Techniques
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microscopy, Confocal
- Myography
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide/metabolism
- Norepinephrine/pharmacology
- Quinoxalines/pharmacology
- Receptors, Adrenergic, alpha-2/drug effects
- Receptors, Adrenergic, alpha-2/genetics
- Vasoconstrictor Agents/pharmacology
- Vasodilation/drug effects
Collapse
Affiliation(s)
- Majid Malekzadeh Shafaroudi
- Autonomic Physiology Unit, Institute of Biomedical and Life Sciences, West Medical Bldg., University of Glasgow, Glasgow G12 8QQ, Scotland, UK
| | | | | | | | | | | | | |
Collapse
|