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Brewster LM, van den Born BJ, van Montfrans GA. Lifetime prevalence and correlates of syncope in five ancestry groups. The HELIUS study. IJC HEART & VASCULATURE 2022; 43:101143. [DOI: 10.1016/j.ijcha.2022.101143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/29/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022]
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The Potential Role of Creatine in Vascular Health. Nutrients 2021; 13:nu13030857. [PMID: 33807747 PMCID: PMC7999364 DOI: 10.3390/nu13030857] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/24/2021] [Accepted: 03/04/2021] [Indexed: 12/11/2022] Open
Abstract
Creatine is an organic compound, consumed exogenously in the diet and synthesized endogenously via an intricate inter-organ process. Functioning in conjunction with creatine kinase, creatine has long been known for its pivotal role in cellular energy provision and energy shuttling. In addition to the abundance of evidence supporting the ergogenic benefits of creatine supplementation, recent evidence suggests a far broader application for creatine within various myopathies, neurodegenerative diseases, and other pathologies. Furthermore, creatine has been found to exhibit non-energy related properties, contributing as a possible direct and in-direct antioxidant and eliciting anti-inflammatory effects. In spite of the new clinical success of supplemental creatine, there is little scientific insight into the potential effects of creatine on cardiovascular disease (CVD), the leading cause of mortality. Taking into consideration the non-energy related actions of creatine, highlighted in this review, it can be speculated that creatine supplementation may serve as an adjuvant therapy for the management of vascular health in at-risk populations. This review, therefore, not only aims to summarize the current literature surrounding creatine and vascular health, but to also shed light onto the potential mechanisms in which creatine may be able to serve as a beneficial supplement capable of imparting vascular-protective properties and promoting vascular health.
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Brewster LM, Haan YC, Zwinderman AH, van den Born BJ, van Montfrans GA. CK (Creatine Kinase) Is Associated With Cardiovascular Hemodynamics: The HELIUS Study. Hypertension 2020; 76:373-380. [PMID: 32594803 DOI: 10.1161/hypertensionaha.120.14675] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The ATP-regenerating enzyme CK (creatine kinase) is strongly associated with blood pressure, which lowers upon experimental CK inhibition. The enzyme is thought to affect cardiovascular hemodynamics through enhanced systemic vascular resistance, stroke volume, and cardiac contractility, but data on these parameters are lacking. We hereby report hemodynamics by CK levels in the multiethnic, cross-sectional HELIUS study (Healthy Life in an Urban Setting). Physical examination included sitting brachial blood pressure and noninvasively assessed supine systemic vascular resistance, stroke volume, cardiac output, and cardiac contractility, which we associated with resting plasma CK. Data from 14 937 men and women (mean age, 43.3; SD, 12.9) indicated that per log CK increase, blood pressure increased with 20.2 (18.9-21.4) mm Hg systolic/13.0 (12.2-13.7) diastolic, an odds ratio for hypertension of 6.1 (5.1-7.2). Outcomes were similar by sex, body mass index, and ancestry, although higher blood pressures in men, with overweight/obesity, and West-African ancestry were partially explained by higher CK, with an adjusted increase in systolic/diastolic pressure of 10.5 (10.0-10.9)/6.4 (6.0-6.7) mm Hg per log CK increase. Systemic vascular resistance, stroke volume, cardiac output, and cardiac contractility (n=7876), increased by respectively 20%, 39%, 14%, and 23% SD per log CK increase. This study indicates that the association of CK with blood pressure likely results from an increase in systemic vascular resistance and stroke volume. These data expand the knowledge on the nature of hypertension associated with CK and may inform further experiments on CK inhibition as a means to lower blood pressure.
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Affiliation(s)
| | - Yentl C Haan
- Departments of Vascular Medicine (Y.C.H., B.J.v.d.B.), Amsterdam UMC, the Netherlands
| | - Aeilko H Zwinderman
- Clinical Epidemiology and Biostatistics (A.H.Z.), Amsterdam UMC, the Netherlands
| | - Bert Jan van den Born
- Departments of Vascular Medicine (Y.C.H., B.J.v.d.B.), Amsterdam UMC, the Netherlands
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Brewster LM, Oudman I, Nannan Panday RV, Khoyska I, Haan YC, Karamat FA, Clark JF, van Montfrans GA. Creatine kinase and renal sodium excretion in African and European men on a high sodium diet. J Clin Hypertens (Greenwich) 2018; 20:334-341. [PMID: 29357199 DOI: 10.1111/jch.13182] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/26/2017] [Accepted: 09/30/2017] [Indexed: 01/11/2023]
Abstract
Creatine kinase (CK) rapidly regenerates ATP for Na+ /K+ -ATPase driven sodium retention throughout the kidney. Therefore, we assessed whether resting plasma CK is associated with sodium retention after a high sodium diet. Sixty healthy men (29 European and 31 African ancestry) with a mean age of 37.2 years (SE 1.2) were assigned to low sodium intake (< 50 mmol/d) during 7 days, followed by 3 days of high sodium intake (> 200 mmol/d). Sodium excretion (mmol/24-h) after high sodium was 260.4 (28.3) in the high CK tertile versus 415.2 (26.3) mmol/24-h in the low CK tertile (P < .001), with a decrease in urinary sodium excretion of 98.4 mmol/24-h for each increase in log CK, adjusted for age and African ancestry. These preliminary results are in line with the energy buffering function of the CK system, but more direct assessments of kidney CK will be needed to further establish whether this enzyme enhances sodium sensitivity.
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Affiliation(s)
- Lizzy M Brewster
- Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Inge Oudman
- Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Rani V Nannan Panday
- Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Inna Khoyska
- Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Yentl C Haan
- Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Fares A Karamat
- Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Joseph F Clark
- The Vontz Center for Molecular Studies, University of Cincinnati, Cincinnati, OH, USA
| | - Gert A van Montfrans
- Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Increasing creatine kinase activity protects against hypoxia / reoxygenation injury but not against anthracycline toxicity in vitro. PLoS One 2017; 12:e0182994. [PMID: 28806770 PMCID: PMC5555628 DOI: 10.1371/journal.pone.0182994] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 07/27/2017] [Indexed: 02/03/2023] Open
Abstract
The creatine kinase (CK) phosphagen system is fundamental to cellular energy homeostasis. Cardiomyocytes express three CK isoforms, namely the mitochondrial sarcomeric CKMT2 and the cytoplasmic CKM and CKB. We hypothesized that augmenting CK in vitro would preserve cell viability and function and sought to determine efficacy of the various isoforms. The open reading frame of each isoform was cloned into pcDNA3.1, followed by transfection and stable selection in human embryonic kidney cells (HEK293). CKMT2- CKM- and CKB-HEK293 cells had increased protein and total CK activity compared to non-transfected cells. Overexpressing any of the three CK isoforms reduced cell death in response to 18h hypoxia at 1% O2 followed by 2h re-oxygenation as assayed using propidium iodide: by 33% in CKMT2, 47% in CKM and 58% in CKB compared to non-transfected cells (P<0.05). Loading cells with creatine did not modify cell survival. Transient expression of CK isoforms in HL-1 cardiac cells elevated isoenzyme activity, but only CKMT2 over-expression protected against hypoxia (0.1% for 24h) and reoxygenation demonstrating 25% less cell death compared to non-transfected control (P<0.01). The same cells were not protected from doxorubicin toxicity (250nM for 48h), in contrast to the positive control. These findings support increased CK activity as protection against ischaemia-reperfusion injury, in particular, protection via CKMT2 in a cardiac-relevant cell line, which merits further investigation in vivo.
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Baldissera MD, Souza CF, Júnior GB, Verdi CM, Moreira KLS, da Rocha MIUM, da Veiga ML, Santos RCV, Vizzotto BS, Baldisserotto B. Aeromonas caviae alters the cytosolic and mitochondrial creatine kinase activities in experimentally infected silver catfish: Impairment on renal bioenergetics. Microb Pathog 2017; 110:439-443. [PMID: 28735082 DOI: 10.1016/j.micpath.2017.07.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 07/17/2017] [Accepted: 07/17/2017] [Indexed: 01/01/2023]
Abstract
Cytosolic and mitochondrial creatine kinases (CK), through the creatine kinase-phosphocreatine (CK/PCr) system, provide a temporal and spatial energy buffer to maintain cellular energy homeostasis. However, the effects of bacterial infections on the kidney remain poorly understood and are limited only to histopathological analyses. Thus, the aim of this study was to investigate the involvement of cytosolic and mitochondrial CK activities in renal energetic homeostasis in silver catfish experimentally infected with Aeromonas caviae. Cytosolic CK activity decreased in infected animals, while mitochondrial CK activity increased compared to uninfected animals. Moreover, the activity of the sodium-potassium pump (Na+, K+-ATPase) decreased in infected animals compared to uninfected animals. Based on this evidence, it can be concluded that the inhibition of cytosolic CK activity by A. caviae causes an impairment on renal energy homeostasis through the depletion of adenosine triphosphate (ATP) levels. This contributes to the inhibition of Na+, K+-ATPase activity, although the mitochondrial CK activity acted in an attempt to restore the cytosolic ATP levels through a feedback mechanism. In summary, A. caviae infection causes a severe energetic imbalance in infected silver catfish, which may contribute to disease pathogenesis.
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Affiliation(s)
- Matheus D Baldissera
- Department of Microbiology and Parasitology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
| | - Carine F Souza
- Department of Physiology and Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Guerino B Júnior
- Department of Physiology and Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Camila Marina Verdi
- Department of Microbiology and Parasitology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Karen L S Moreira
- Department of Morphology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | | | - Marcelo L da Veiga
- Department of Morphology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil
| | - Roberto C V Santos
- Department of Microbiology and Parasitology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Bruno S Vizzotto
- Laboratory of Molecular Biology, Centro Universitário Franciscano, Santa Maria, RS, Brazil
| | - Bernardo Baldisserotto
- Department of Physiology and Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
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Wallimann T, Riek U, Möddel M. Intradialytic creatine supplementation: A scientific rationale for improving the health and quality of life of dialysis patients. Med Hypotheses 2017; 99:1-14. [DOI: 10.1016/j.mehy.2016.12.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 12/03/2016] [Indexed: 12/19/2022]
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Creatine kinase inhibition lowers systemic arterial blood pressure in spontaneously hypertensive rats. J Hypertens 2016; 34:2418-2426. [DOI: 10.1097/hjh.0000000000001090] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Prá M, Ferreira GK, de Mello AH, Schraiber RDB, Cardoso LC, Souza LDR, da Rosa N, Fortunato JJ, Rezin GT. Single dose and repeated administrations of liraglutide alter energy metabolism in the brains of young and adult rats. Biochem Cell Biol 2016; 94:451-458. [PMID: 27563837 DOI: 10.1139/bcb-2016-0016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Liraglutide is a human glucagon-like peptide-1 (GLP-1) analogue that was recently approved to treat obesity in some countries. Considering that liraglutide effects on brain energy metabolism are little known, we evaluated the effects of liraglutide on the energy metabolism. Animals received a single or daily injection of saline or liraglutide during 7 days (25, 50, 100, or 300 μg/kg i.p.). Twenty-four hours after the single or last injection, the rats were euthanized and the hypothalamus, prefrontal cortex, cerebellum, hippocampus, striatum, and posterior cortex were isolated. Our results demonstrated that a single dose of liraglutide in young rats increased the activity of complexes and inhibited creatine kinase activity. Repeated administrations of liraglutide in young rats reduced the activity of complexes and activated creatine kinase activity. In adult rats, a single dose of liraglutide reduced the activity of complex I and creatine kinase and increased the activity of complexes II and IV. Repeated administrations of liraglutide in adult rats increased the activity of complexes I and IV and reduced the activity of complex II and creatine kinase. We concluded that liraglutide may interfere in energy metabolism, because analysis of different times of administrations, concentrations, and level of brain development leads to divergent results.
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Affiliation(s)
- Morgana Prá
- a Laboratory of Clinical and Experimental Pathophysiology, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Gabriela Kozuchovski Ferreira
- b Laboratory Pharmacology and Pathophysiology of Skin, Department of Pharmacology, Federal University of Paraná, Curitiba, 81531-980 PR, Brazil
| | - Aline Haas de Mello
- a Laboratory of Clinical and Experimental Pathophysiology, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Rosiane de Bona Schraiber
- a Laboratory of Clinical and Experimental Pathophysiology, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Larissa Colonetti Cardoso
- a Laboratory of Clinical and Experimental Pathophysiology, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Luana da Rosa Souza
- a Laboratory of Clinical and Experimental Pathophysiology, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Naiana da Rosa
- c Laboratory of Neuroscience, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Jucélia Jeremias Fortunato
- c Laboratory of Neuroscience, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
| | - Gislaine Tezza Rezin
- a Laboratory of Clinical and Experimental Pathophysiology, Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Tubarão, 88704-900 SC, Brazil
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Cellular compartmentation of energy metabolism: creatine kinase microcompartments and recruitment of B-type creatine kinase to specific subcellular sites. Amino Acids 2016; 48:1751-74. [DOI: 10.1007/s00726-016-2267-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 05/27/2016] [Indexed: 12/13/2022]
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Ellery SJ, LaRosa DA, Kett MM, Della Gatta PA, Snow RJ, Walker DW, Dickinson H. Dietary creatine supplementation during pregnancy: a study on the effects of creatine supplementation on creatine homeostasis and renal excretory function in spiny mice. Amino Acids 2015; 48:1819-30. [PMID: 26695944 DOI: 10.1007/s00726-015-2150-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/01/2015] [Indexed: 12/23/2022]
Abstract
Recent evidence obtained from a rodent model of birth asphyxia shows that supplementation of the maternal diet with creatine during pregnancy protects the neonate from multi-organ damage. However, the effect of increasing creatine intake on creatine homeostasis and biosynthesis in females, particularly during pregnancy, is unknown. This study assessed the impact of creatine supplementation on creatine homeostasis, body composition, capacity for de novo creatine synthesis and renal excretory function in non-pregnant and pregnant spiny mice. Mid-gestation pregnant and virgin spiny mice were fed normal chow or chow supplemented with 5 % w/w creatine for 18 days. Weight gain, urinary creatine and electrolyte excretion were assessed during supplementation. At post mortem, body composition was assessed by Dual-energy X-ray absorptiometry, or tissues were collected to assess creatine content and mRNA expression of the creatine synthesising enzymes arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT) and the creatine transporter (CrT1). Protein expression of AGAT and GAMT was also assessed by Western blot. Key findings of this study include no changes in body weight or composition with creatine supplementation; increased urinary creatine excretion in supplemented spiny mice, with increased sodium (P < 0.001) and chloride (P < 0.05) excretion in pregnant dams after 3 days of supplementation; lowered renal AGAT mRNA (P < 0.001) and protein (P < 0.001) expressions, and lowered CrT1 mRNA expression in the kidney (P < 0.01) and brain (P < 0.001). Creatine supplementation had minimal impact on creatine homeostasis in either non-pregnant or pregnant spiny mice. Increasing maternal dietary creatine consumption could be a useful treatment for birth asphyxia.
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Affiliation(s)
- Stacey J Ellery
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Melbourne, 3168, Australia. .,Department of Obstetrics and Gynecology, Monash University, Monash Medical Centre, Clayton, Melbourne, Australia.
| | - Domenic A LaRosa
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Melbourne, 3168, Australia.,Department of Obstetrics and Gynecology, Monash University, Monash Medical Centre, Clayton, Melbourne, Australia
| | - Michelle M Kett
- Department of Physiology, Monash University, Clayton Campus, Melbourne, Australia
| | - Paul A Della Gatta
- Centre for Physical Activity and Nutrition, Deakin University, Burwood Campus, Melbourne, Australia
| | - Rod J Snow
- Centre for Physical Activity and Nutrition, Deakin University, Burwood Campus, Melbourne, Australia
| | - David W Walker
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Melbourne, 3168, Australia.,Department of Obstetrics and Gynecology, Monash University, Monash Medical Centre, Clayton, Melbourne, Australia
| | - Hayley Dickinson
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Melbourne, 3168, Australia.,Department of Obstetrics and Gynecology, Monash University, Monash Medical Centre, Clayton, Melbourne, Australia
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Venter G, Polling S, Pluk H, Venselaar H, Wijers M, Willemse M, Fransen JAM, Wieringa B. Submembranous recruitment of creatine kinase B supports formation of dynamic actin-based protrusions of macrophages and relies on its C-terminal flexible loop. Eur J Cell Biol 2014; 94:114-27. [PMID: 25538032 DOI: 10.1016/j.ejcb.2014.11.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 11/05/2014] [Accepted: 11/06/2014] [Indexed: 12/20/2022] Open
Abstract
Subcellular partitioning of creatine kinase contributes to the formation of patterns in intracellular ATP distribution and the fuelling of cellular processes with a high and sudden energy demand. We have previously shown that brain-type creatine kinase (CK-B) accumulates at the phagocytic cup in macrophages where it is involved in the compartmentalized generation of ATP for actin remodeling. Here, we report that CK-B catalytic activity also helps in the formation of protrusive ruffle structures which are actin-dependent and abundant on the surface of both unstimulated and LPS-activated macrophages. Recruitment of CK-B to these structures occurred transiently and inhibition of the enzyme's catalytic activity with cyclocreatine led to a general smoothening of surface morphology as visualized by scanning electron microscopy. Comparison of the dynamics of distribution of YFP-tagged CK-mutants and isoforms by live imaging revealed that amino acid residues in the C-terminal segment (aa positions 323-330) that forms one of the protein's two mobile loops are involved in partitioning over inner regions of the cytosol and nearby sites where membrane protrusions occur during induction of phagocytic cup formation. Although wt CK-B, muscle-type CK (CK-M), and a catalytically dead CK-B-E232Q mutant with intact loop region were normally recruited from the cytosolic pool, no dynamic transition to the phagocytic cup area was seen for the CK-homologue arginine kinase and a CK-B-D326A mutant protein. Bioinformatics analysis helped us to predict that conformational flexibility of the C-terminal loop, independent of conformational changes induced by substrate binding or catalytic activity, is likely involved in exposing the enzyme for binding at or near the sites of membrane protrusion formation.
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Affiliation(s)
- Gerda Venter
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Saskia Polling
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Helma Pluk
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Hanka Venselaar
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Mietske Wijers
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Marieke Willemse
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Jack A M Fransen
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Bé Wieringa
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
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Muscle involvement in Dent disease 2. Pediatr Nephrol 2014; 29:2127-32. [PMID: 24912603 DOI: 10.1007/s00467-014-2841-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/22/2014] [Accepted: 04/25/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Dent disease, an X-linked recessive renal tubulopathy, is caused by mutations in either CLCN5 (Dent disease 1) or OCRL (Dent disease 2). OCRL mutations can also cause Lowe syndrome. In some cases it is difficult to differentiate Dent disease 1 and 2 on the basis of clinical features only without genetic tests. Several studies have shown differences in serum levels of muscle enzymes between these diseases. The aim of our study was to test the validity of these findings. METHODS In total, 23 patients with Dent disease 1 (Group A), five patients with Dent disease 2 (Group B) and 19 patients with Lowe syndrome (Group C) were enrolled in our study. The serum levels of three muscle enzymes [creatine phosphokinase (CPK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST)], were measured. The levels of a hepatic enzyme, alanine aminotransferase (ALT), were also measured as a control. RESULTS One patient in Group B had muscle hypoplasia of both upper extremities. The serum levels of all three muscle enzymes assayed were higher in Group B or C patients than in Group A patients. Serum ALT levels were normal in all three groups of patients. CONCLUSIONS The serum levels of muscle enzymes in patients with Dent disease can be used as a biomarker to predict genotypes, even though the patients do not have clinical symptoms of muscle involvement.
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14
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Investigating the association between creatine kinase and failure of antihypertensive treatment. J Hypertens 2013; 31:1915. [DOI: 10.1097/hjh.0b013e328363a4c9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Brewster LM, Seedat YK. Why do hypertensive patients of African ancestry respond better to calcium blockers and diuretics than to ACE inhibitors and β-adrenergic blockers? A systematic review. BMC Med 2013; 11:141. [PMID: 23721258 PMCID: PMC3681568 DOI: 10.1186/1741-7015-11-141] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Accepted: 04/17/2013] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Clinicians are encouraged to take an individualized approach when treating hypertension in patients of African ancestry, but little is known about why the individual patient may respond well to calcium blockers and diuretics, but generally has an attenuated response to drugs inhibiting the renin-angiotensin system and to β-adrenergic blockers. Therefore, we systematically reviewed the factors associated with the differential drug response of patients of African ancestry to antihypertensive drug therapy. METHODS Using the methodology of the systematic reviews narrative synthesis approach, we sought for published or unpublished studies that could explain the differential clinical efficacy of antihypertensive drugs in patients of African ancestry. PUBMED, EMBASE, LILACS, African Index Medicus and the Food and Drug Administration and European Medicines Agency databases were searched without language restriction from their inception through June 2012. RESULTS We retrieved 3,763 papers, and included 72 reports that mainly considered the 4 major classes of antihypertensive drugs, calcium blockers, diuretics, drugs that interfere with the renin-angiotensin system and β-adrenergic blockers. Pharmacokinetics, plasma renin and genetic polymorphisms did not well predict the response of patients of African ancestry to antihypertensive drugs. An emerging view that low nitric oxide and high creatine kinase may explain individual responses to antihypertensive drugs unites previous observations, but currently clinical data are very limited. CONCLUSION Available data are inconclusive regarding why patients of African ancestry display the typical response to antihypertensive drugs. In lieu of biochemical or pharmacogenomic parameters, self-defined African ancestry seems the best available predictor of individual responses to antihypertensive drugs.
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Affiliation(s)
- Lizzy M Brewster
- Departments of Internal and Vascular Medicine, F4-222, Academic Medical Center, Meibergdreef 9, Amsterdam, AZ, 1105, The Netherlands.
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16
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Abplanalp J, Laczko E, Philp NJ, Neidhardt J, Zuercher J, Braun P, Schorderet DF, Munier FL, Verrey F, Berger W, Camargo SM, Kloeckener-Gruissem B. The cataract and glucosuria associated monocarboxylate transporter MCT12 is a new creatine transporter. Hum Mol Genet 2013. [DOI: 78495111110.1093/hmg/ddt175' target='_blank'>'"<>78495111110.1093/hmg/ddt175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [78495111110.1093/hmg/ddt175','', '10.1152/ajpcell.1997.272.2.c697')">Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
78495111110.1093/hmg/ddt175" />
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17
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Abplanalp J, Laczko E, Philp NJ, Neidhardt J, Zuercher J, Braun P, Schorderet DF, Munier FL, Verrey F, Berger W, Camargo SMR, Kloeckener-Gruissem B. The cataract and glucosuria associated monocarboxylate transporter MCT12 is a new creatine transporter. Hum Mol Genet 2013; 22:3218-26. [PMID: 23578822 DOI: 10.1093/hmg/ddt175] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Creatine transport has been assigned to creatine transporter 1 (CRT1), encoded by mental retardation associated SLC6A8. Here, we identified a second creatine transporter (CRT2) known as monocarboxylate transporter 12 (MCT12), encoded by the cataract and glucosuria associated gene SLC16A12. A non-synonymous alteration in MCT12 (p.G407S) found in a patient with age-related cataract (ARC) leads to a significant reduction of creatine transport. Furthermore, Slc16a12 knockout (KO) rats have elevated creatine levels in urine. Transport activity and expression characteristics of the two creatine transporters are distinct. CRT2 (MCT12)-mediated uptake of creatine was not sensitive to sodium and chloride ions or creatine biosynthesis precursors, breakdown product creatinine or creatine phosphate. Increasing pH correlated with increased creatine uptake. Michaelis-Menten kinetics yielded a Vmax of 838.8 pmol/h/oocyte and a Km of 567.4 µm. Relative expression in various human tissues supports the distinct mutation-associated phenotypes of the two transporters. SLC6A8 was predominantly found in brain, heart and muscle, while SLC16A12 was more abundant in kidney and retina. In the lens, the two transcripts were found at comparable levels. We discuss the distinct, but possibly synergistic functions of the two creatine transporters. Our findings infer potential preventive power of creatine supplementation against the most prominent age-related vision impaired condition.
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Affiliation(s)
- Jeannette Abplanalp
- Institute of Medical Molecular Genetics, University of Zurich, Zurich, Switzerland
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18
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Schmid H, Tokarska-Schlattner M, Füeßl B, Röder M, Kay L, Attia S, Lederer SR, Goebel FD, Schlattner U, Bogner JR. Macro CK2 accumulation in tenofovir-treated HIV patients is facilitated by CK oligomer stabilization but is not predictive for pathology. Antivir Ther 2012; 18:193-204. [PMID: 22894916 DOI: 10.3851/imp2313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/20/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Ubiquitous mitochondrial creatine kinase (uMtCK) accumulates as macroenzyme creatine kinase type 2 (macro CK2) in the serum of HIV-infected patients under a tenofovir disoproxil fumarate (TDF)-containing antiretroviral regimen. The genesis and clinical significance of this finding is unclear. METHODS A prospective observational 5-year follow-up study was performed on those patients in which macro CK2 appearance was initially described ('TDF switch study' cohort). In addition, tenofovir (TFV), its prodrug TDF and its active, intracellular derivative TFV diphosphate (TDP) were tested in vitro for their effects on different key properties of uMtCK to clarify possible interactions of uMtCK with TFV compounds. RESULTS In just under 5 years of continuous TDF treatment, only 4/12 (33%) patients remained macro CK2-positive, whereas 8/12 (66%) originally positive patients were macro CK2-negative at the end of follow-up. Prospective clinical follow-up data indicate that macro CK2 appearance under TDF is not associated with significant cell damage or occurrence of malignancies. A trend towards grade 1 hypophosphataemia suggests subclinical proximal tubular dysfunction in macro-CK2-positive patients, although it was not associated with a significant decrease in estimated glomerular filtration rate. In vitro, TFV, TDF and TDP did not interfere with uMtCK enzyme activity as competitive inhibitors or pseudo-substrates, but TFV and TDF stabilized the native uMtCK octameric structure in dilute solutions. CONCLUSIONS Appearance of octameric uMtCK as macro CK2 in the serum of TDF-treated patients is suggested to result from a combination of low-level mitochondrial damage caused by subclinical renal tubular dysfunction together with possible compensatory uMtCK overexpression and a putative concomitant stabilization of uMtCK octamers by higher levels of TFV in proximal tubules.
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Affiliation(s)
- Holger Schmid
- Section of Infectious Diseases, Clinic and Policlinic IV, University of Munich, Munich, Germany.
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19
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Genius J, Geiger J, Bender A, Möller HJ, Klopstock T, Rujescu D. Creatine protects against excitoxicity in an in vitro model of neurodegeneration. PLoS One 2012; 7:e30554. [PMID: 22347384 PMCID: PMC3275587 DOI: 10.1371/journal.pone.0030554] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 12/19/2011] [Indexed: 12/30/2022] Open
Abstract
Creatine has been shown to be neuroprotective in aging, neurodegenerative conditions and brain injury. As a common molecular background, oxidative stress and disturbed cellular energy homeostasis are key aspects in these conditions. Moreover, in a recent report we could demonstrate a life-enhancing and health-promoting potential of creatine in rodents, mainly due to its neuroprotective action. In order to investigate the underlying pharmacology mediating these mainly neuroprotective properties of creatine, cultured primary embryonal hippocampal and cortical cells were challenged with glutamate or H2O2. In good agreement with our in vivo data, creatine mediated a direct effect on the bioenergetic balance, leading to an enhanced cellular energy charge, thereby acting as a neuroprotectant. Moreover, creatine effectively antagonized the H2O2-induced ATP depletion and the excitotoxic response towards glutamate, while not directly acting as an antioxidant. Additionally, creatine mediated a direct inhibitory action on the NMDA receptor-mediated calcium response, which initiates the excitotoxic cascade. Even excessive concentrations of creatine had no neurotoxic effects, so that high-dose creatine supplementation as a health-promoting agent in specific pathological situations or as a primary prophylactic compound in risk populations seems feasible. In conclusion, we were able to demonstrate that the protective potential of creatine was primarily mediated by its impact on cellular energy metabolism and NMDA receptor function, along with reduced glutamate spillover, oxidative stress and subsequent excitotoxicity.
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Affiliation(s)
- Just Genius
- Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany
| | - Johanna Geiger
- Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany
| | - Andreas Bender
- Department of Neurology, Ludwig-Maximilians-University, Munich, Germany
| | - Hans-Jürgen Möller
- Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany
| | - Thomas Klopstock
- Department of Neurology, Ludwig-Maximilians-University, Munich, Germany
| | - Dan Rujescu
- Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany
- * E-mail:
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20
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Molecular system bioenergics of the heart: experimental studies of metabolic compartmentation and energy fluxes versus computer modeling. Int J Mol Sci 2011; 12:9296-331. [PMID: 22272134 PMCID: PMC3257131 DOI: 10.3390/ijms12129296] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 11/30/2011] [Accepted: 11/30/2011] [Indexed: 12/11/2022] Open
Abstract
In this review we analyze the recent important and remarkable advancements in studies of compartmentation of adenine nucleotides in muscle cells due to their binding to macromolecular complexes and cellular structures, which results in non-equilibrium steady state of the creatine kinase reaction. We discuss the problems of measuring the energy fluxes between different cellular compartments and their simulation by using different computer models. Energy flux determinations by 18O transfer method have shown that in heart about 80% of energy is carried out of mitochondrial intermembrane space into cytoplasm by phosphocreatine fluxes generated by mitochondrial creatine kinase from adenosine triphosphate (ATP), produced by ATP Synthasome. We have applied the mathematical model of compartmentalized energy transfer for analysis of experimental data on the dependence of oxygen consumption rate on heart workload in isolated working heart reported by Williamson et al. The analysis of these data show that even at the maximal workloads and respiration rates, equal to 174 μmol O2 per min per g dry weight, phosphocreatine flux, and not ATP, carries about 80–85% percent of energy needed out of mitochondria into the cytosol. We analyze also the reasons of failures of several computer models published in the literature to correctly describe the experimental data.
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21
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Wallimann T, Tokarska-Schlattner M, Schlattner U. The creatine kinase system and pleiotropic effects of creatine. Amino Acids 2011; 40:1271-96. [PMID: 21448658 PMCID: PMC3080659 DOI: 10.1007/s00726-011-0877-3] [Citation(s) in RCA: 462] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Accepted: 12/02/2010] [Indexed: 11/24/2022]
Abstract
The pleiotropic effects of creatine (Cr) are based mostly on the functions of the enzyme creatine kinase (CK) and its high-energy product phosphocreatine (PCr). Multidisciplinary studies have established molecular, cellular, organ and somatic functions of the CK/PCr system, in particular for cells and tissues with high and intermittent energy fluctuations. These studies include tissue-specific expression and subcellular localization of CK isoforms, high-resolution molecular structures and structure–function relationships, transgenic CK abrogation and reverse genetic approaches. Three energy-related physiological principles emerge, namely that the CK/PCr systems functions as (a) an immediately available temporal energy buffer, (b) a spatial energy buffer or intracellular energy transport system (the CK/PCr energy shuttle or circuit) and (c) a metabolic regulator. The CK/PCr energy shuttle connects sites of ATP production (glycolysis and mitochondrial oxidative phosphorylation) with subcellular sites of ATP utilization (ATPases). Thus, diffusion limitations of ADP and ATP are overcome by PCr/Cr shuttling, as most clearly seen in polar cells such as spermatozoa, retina photoreceptor cells and sensory hair bundles of the inner ear. The CK/PCr system relies on the close exchange of substrates and products between CK isoforms and ATP-generating or -consuming processes. Mitochondrial CK in the mitochondrial outer compartment, for example, is tightly coupled to ATP export via adenine nucleotide transporter or carrier (ANT) and thus ATP-synthesis and respiratory chain activity, releasing PCr into the cytosol. This coupling also reduces formation of reactive oxygen species (ROS) and inhibits mitochondrial permeability transition, an early event in apoptosis. Cr itself may also act as a direct and/or indirect anti-oxidant, while PCr can interact with and protect cellular membranes. Collectively, these factors may well explain the beneficial effects of Cr supplementation. The stimulating effects of Cr for muscle and bone growth and maintenance, and especially in neuroprotection, are now recognized and the first clinical studies are underway. Novel socio-economically relevant applications of Cr supplementation are emerging, e.g. for senior people, intensive care units and dialysis patients, who are notoriously Cr-depleted. Also, Cr will likely be beneficial for the healthy development of premature infants, who after separation from the placenta depend on external Cr. Cr supplementation of pregnant and lactating women, as well as of babies and infants are likely to be of benefit for child development. Last but not least, Cr harbours a global ecological potential as an additive for animal feed, replacing meat- and fish meal for animal (poultry and swine) and fish aqua farming. This may help to alleviate human starvation and at the same time prevent over-fishing of oceans.
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Affiliation(s)
- Theo Wallimann
- Institute of Cell Biology, ETH Zurich, Zurich, Switzerland.
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22
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Dowd WW, Renshaw GMC, Cech JJ, Kültz D. Compensatory proteome adjustments imply tissue-specific structural and metabolic reorganization following episodic hypoxia or anoxia in the epaulette shark (Hemiscyllium ocellatum). Physiol Genomics 2010; 42:93-114. [PMID: 20371547 PMCID: PMC2888556 DOI: 10.1152/physiolgenomics.00176.2009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Accepted: 04/05/2010] [Indexed: 12/31/2022] Open
Abstract
The epaulette shark (Hemiscyllium ocellatum) represents an ancestral vertebrate model of episodic hypoxia and anoxia tolerance at tropical temperatures. We used two-dimensional gel electrophoresis and mass spectrometry-based proteomics approaches, combined with a suite of physiological measures, to characterize this species' responses to 1) one episode of anoxia plus normoxic recovery, 2) one episode of severe hypoxia plus recovery, or 3) two episodes of severe hypoxia plus recovery. We examined these responses in the cerebellum and rectal gland, two tissues with high ATP requirements. Sharks maintained plasma ionic homeostasis following all treatments, and activities of Na(+)/K(+)-ATPase and caspase 3/7 in both tissues were unchanged. Oxygen lack and reoxygenation elicited subtle adjustments in the proteome. Hypoxia led to more extensive proteome responses than anoxia in both tissues. The cerebellum and rectal gland exhibited treatment-specific responses to oxygen limitation consistent with one or more of several strategies: 1) neurotransmitter and receptor downregulation in cerebellum to prevent excitotoxicity, 2) cytoskeletal/membrane reorganization, 3) metabolic reorganization and more efficient intracellular energy shuttling that are more consistent with sustained ATP turnover than with long-term metabolic depression, 4) detoxification of metabolic byproducts and oxidative stress in light of continued metabolic activity, particularly following hypoxia in rectal gland, and 5) activation of prosurvival signaling. We hypothesize that neuronal morphological changes facilitate prolonged protection from excitotoxicity via dendritic spine remodeling in cerebellum (i.e., synaptic structural plasticity). These results recapitulate several highly conserved themes in the anoxia and hypoxia tolerance, preconditioning, and oxidative stress literature in a single system. In addition, several of the identified pathways and proteins suggest potentially novel mechanisms for enhancing anoxia or hypoxia tolerance in vertebrates. Overall, our data show that episodic hypoxic or anoxic exposure and recovery in the epaulette shark amplifies a constitutive suite of compensatory mechanisms that further prepares them for subsequent insults.
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Affiliation(s)
- W Wesley Dowd
- Department of Animal Science, University of California, Davis, California, USA
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23
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Li H, Thali RF, Smolak C, Gong F, Alzamora R, Wallimann T, Scholz R, Pastor-Soler NM, Neumann D, Hallows KR. Regulation of the creatine transporter by AMP-activated protein kinase in kidney epithelial cells. Am J Physiol Renal Physiol 2010; 299:F167-77. [PMID: 20462973 DOI: 10.1152/ajprenal.00162.2010] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The metabolic sensor AMP-activated protein kinase (AMPK) regulates several transport proteins, potentially coupling transport activity to cellular stress and energy levels. The creatine transporter (CRT; SLC6A8) mediates creatine uptake into several cell types, including kidney epithelial cells, where it has been proposed that CRT is important for reclamation of filtered creatine, a process critical for total body creatine homeostasis. Creatine and phosphocreatine provide an intracellular, high-energy phosphate-buffering system essential for maintaining ATP supply in tissues with high energy demands. To test our hypothesis that CRT is regulated by AMPK in the kidney, we examined CRT and AMPK distribution in the kidney and the regulation of CRT by AMPK in cells. By immunofluorescence staining, we detected CRT at the apical pole in a polarized mouse S3 proximal tubule cell line and in native rat kidney proximal tubules, a distribution overlapping with AMPK. Two-electrode voltage-clamp (TEV) measurements of Na(+)-dependent creatine uptake into CRT-expressing Xenopus laevis oocytes demonstrated that AMPK inhibited CRT via a reduction in its Michaelis-Menten V(max) parameter. [(14)C]creatine uptake and apical surface biotinylation measurements in polarized S3 cells demonstrated parallel reductions in creatine influx and CRT apical membrane expression after AMPK activation with the AMP-mimetic compound 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside. In oocyte TEV experiments, rapamycin and the AMPK activator 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranosyl 5'-monophosphate (ZMP) inhibited CRT currents, but there was no additive inhibition of CRT by ZMP, suggesting that AMPK may inhibit CRT indirectly via the mammalian target of rapamycin pathway. We conclude that AMPK inhibits apical membrane CRT expression in kidney proximal tubule cells, which could be important in reducing cellular energy expenditure and unnecessary creatine reabsorption under conditions of local and whole body metabolic stress.
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Affiliation(s)
- Hui Li
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA
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24
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Structural studies of human brain-type creatine kinase complexed with the ADP-Mg2+-NO3- -creatine transition-state analogue complex. FEBS Lett 2008; 582:3959-65. [PMID: 18977227 DOI: 10.1016/j.febslet.2008.10.039] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 10/15/2008] [Accepted: 10/21/2008] [Indexed: 11/22/2022]
Abstract
Creatine kinase is a member of the phosphagen kinase family, which catalyzes the reversible phosphoryl transfer reaction that occurs between ATP and creatine to produce ADP and phosphocreatine. Here, three structural aspects of human-brain-type-creatine-kinase (hBB-CK) were identified by X-ray crystallography: the ligand-free-form at 2.2A; the ADP-Mg2+, nitrate, and creatine complex (transition-state-analogue complex; TSAC); and the ADP-Mg2+-complex at 2.0A. The structures of ligand-bound hBB-CK revealed two different monomeric states in a single homodimer. One monomer is a closed form, either bound to TSAC or the ADP-Mg2+-complex, and the second monomer is an unliganded open form. These structural studies provide a detailed mechanism indicating that the binding of ADP-Mg2+ alone may trigger conformational changes in hBB-CK that were not observed with muscle-type-CK.
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25
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Functions and effects of creatine in the central nervous system. Brain Res Bull 2008; 76:329-43. [DOI: 10.1016/j.brainresbull.2008.02.035] [Citation(s) in RCA: 254] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Revised: 02/15/2008] [Accepted: 02/25/2008] [Indexed: 12/12/2022]
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26
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Prass K, Royl G, Lindauer U, Freyer D, Megow D, Dirnagl U, Stöckler-Ipsiroglu G, Wallimann T, Priller J. Improved reperfusion and neuroprotection by creatine in a mouse model of stroke. J Cereb Blood Flow Metab 2007; 27:452-9. [PMID: 16773141 DOI: 10.1038/sj.jcbfm.9600351] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Stroke leads to energy failure and subsequent neuronal cell loss. Creatine and phosphocreatine constitute a cellular energy buffering and transport system, and dietary creatine supplementation was shown to protect neurons in several models of neurodegeneration. Although creatine has recently been found to reduce infarct size after cerebral ischemia in mice, the mechanisms of neuroprotection remained unclear. We provide evidence for augmented cerebral blood flow (CBF) after stroke in creatine-treated mice using a magnetic resonance imaging (MRI)-based technique of CBF measurement (flow-sensitive alternating inversion recovery-MRI). Moreover, improved vasodilatory responses were detected in isolated middle cerebral arteries obtained from creatine-treated animals. After 3 weeks of dietary creatine supplementation, minor changes in brain creatine, phosphocreatine, adenosine triphosphate, adenosine diphosphate and adenosine monophosphate levels were detected, which did not reach statistical significance. However, we found a 40% reduction in infarct volume after transient focal cerebral ischemia. Our data suggest that creatine-mediated neuroprotection can occur independent of changes in the bioenergetic status of brain tissue, but may involve improved cerebrovascular function.
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Affiliation(s)
- Konstantin Prass
- Department of Experimental Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany
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27
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Utsch B, Bökenkamp A, Benz MR, Besbas N, Dötsch J, Franke I, Fründ S, Gok F, Hoppe B, Karle S, Kuwertz-Bröking E, Laube G, Neb M, Nuutinen M, Ozaltin F, Rascher W, Ring T, Tasic V, van Wijk JAE, Ludwig M. Novel OCRL1 mutations in patients with the phenotype of Dent disease. Am J Kidney Dis 2007; 48:942.e1-14. [PMID: 17162149 DOI: 10.1053/j.ajkd.2006.08.018] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Accepted: 08/24/2006] [Indexed: 11/11/2022]
Abstract
BACKGROUND Dent disease is an X-linked tubulopathy frequently caused by mutations affecting the voltage-gated chloride channel and chloride/proton antiporter ClC-5. A recent study showed that defects in OCRL1, encoding a phosphatidylinositol 4,5-bisphosphate 5-phosphatase (Ocrl) and usually found mutated in patients with Lowe syndrome, also can provoke a Dent-like phenotype (Dent 2 disease). METHODS We investigated 20 CLCN5-negative males from 17 families with a phenotype resembling Dent disease for defects in OCRL1. RESULTS In our complete series of 35 families with a phenotype of Dent disease, a mutation in the OCRL1 gene was detected in 6 kindreds. All were novel frameshift (Q70RfsX88 and T121NfsX122, detected twice) or missense mutations (I257T and R476W). None of our patients had cognitive or behavioral impairment or cataracts, 2 classic hallmarks of Lowe syndrome. All patients had mild increases in lactate dehydrogenase and/or creatine kinase levels, which rarely is observed in CLCN5-positive patients, but frequently found in patients with Lowe syndrome. To explain the phenotypic heterogeneity caused by OCRL1 mutations, we performed extensive data-bank mining and extended reverse-transcriptase polymerase chain reaction analysis, which provided no evidence for yet unknown (tissue-specific) alternative OCRL1 transcripts. CONCLUSION Mutations in the OCRL1 gene are found in approximately 23% of kindreds with a Dent phenotype. Defective protein sorting/targeting of Ocrl might be the reason for mildly elevated creatine kinase and lactate dehydrogenase serum concentrations in these patients and a clue to suspect Dent disease unrelated to CLCN5 mutations. It remains to be elucidated why the various OCRL1 mutations found in patients with Dent 2 disease do not cause cataracts.
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Affiliation(s)
- Boris Utsch
- Klinik mit Poliklinik für Kinder und Jugendliche, Universität Erlangen-Nürnberg, Erlangen, Germany
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28
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Bürklen TS, Schlattner U, Homayouni R, Gough K, Rak M, Szeghalmi A, Wallimann T. The creatine kinase/creatine connection to Alzheimer's disease: CK-inactivation, APP-CK complexes and focal creatine deposits. J Biomed Biotechnol 2006; 2006:35936. [PMID: 17047305 PMCID: PMC1510941 DOI: 10.1155/jbb/2006/35936] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 02/28/2006] [Accepted: 02/28/2006] [Indexed: 12/12/2022] Open
Abstract
Cytosolic brain-type creatine kinase (BB-CK), which is coexpressed with ubiquitous mitochondrial uMtCK, is significantly inactivated by oxidation, in Alzheimer's disease (AD) patients. Since CK has been shown to play a fundamental role in cellular energetics of the brain, any disturbance of this enzyme may exasperate the AD disease process. Mutations in amyloid precursor protein (APP) are associated with early onset AD and result in abnormal processing of APP, and accumulation of A beta peptide, the main constituent of amyloid plaques in AD brain. Recent data on a direct interaction between APP and the precursor of uMtCK support an emerging relationship between AD, cellular energy levels and mitochondrial function. In addition, recently discovered creatine (Cr) deposits in the brain of transgenic AD mice, as well as in the hippocampus from AD patients, indicate a direct link between perturbed energy state, Cr metabolism and AD. Here, we review the roles of Cr and Cr-related enzymes and consider the potential value of supplementation with Cr, a potent neuroprotective substance. As a hypothesis, we consider whether Cr, if given at an early time point of the disease, may prevent or delay the course of AD-related neurodegeneration.
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Affiliation(s)
- Tanja S. Bürklen
- Institute of Cell Biology, ETH Zurich,
Hönggerberg HPM, 8093 Zurich, Switzerland
| | - Uwe Schlattner
- Institute of Cell Biology, ETH Zurich,
Hönggerberg HPM, 8093 Zurich, Switzerland
- Laboratory of Fundamental and Applied Bioenergetics,
INSERM E0221, Joseph Fourier University, 38041 Grenoble, Cedex 9, France
| | - Ramin Homayouni
- Department of Neurology, University of Tennessee
Health Science Center, Memphis, TN 38163, USA
| | - Kathleen Gough
- Department of Chemistry, University of Manitoba,
Winnipeg, Manitoba, Canada R3T 2N2
| | - Margaret Rak
- Department of Chemistry, University of Manitoba,
Winnipeg, Manitoba, Canada R3T 2N2
| | - Adriana Szeghalmi
- Department of Chemistry, University of Manitoba,
Winnipeg, Manitoba, Canada R3T 2N2
| | - Theo Wallimann
- Institute of Cell Biology, ETH Zurich,
Hönggerberg HPM, 8093 Zurich, Switzerland
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29
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Andres RH, Huber AW, Schlattner U, Pérez-Bouza A, Krebs SH, Seiler RW, Wallimann T, Widmer HR. Effects of creatine treatment on the survival of dopaminergic neurons in cultured fetal ventral mesencephalic tissue. Neuroscience 2005; 133:701-13. [PMID: 15890457 DOI: 10.1016/j.neuroscience.2005.03.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Revised: 02/10/2005] [Accepted: 03/01/2005] [Indexed: 10/25/2022]
Abstract
Parkinson's disease is a disabling neurodegenerative disorder of unknown etiology characterized by a predominant and progressive loss of dopaminergic neurons in the substantia nigra. Recent findings suggest that impaired energy metabolism plays an important role in the pathogenesis of this disorder. The endogenously occurring guanidino compound creatine is a substrate for mitochondrial and cytosolic creatine kinases. Creatine supplementation improves the function of the creatine kinase/phosphocreatine system by increasing cellular creatine and phosphocreatine levels and the rate of ATP resynthesis. In addition, mitochondrial creatine kinase together with high cytoplasmic creatine levels inhibit mitochondrial permeability transition, a major step in early apoptosis. In the present study, we analyzed the effects of externally added creatine on the survival and morphology of dopaminergic neurons and also addressed its neuroprotective properties in primary cultures of E14 rat ventral mesencephalon. Chronic administration of creatine [5 mM] for 7 days significantly increased survival (by 1.32-fold) and soma size (by 1.12-fold) of dopaminergic neurons, while having no effect on other investigated morphological parameters. Most importantly, concurrent creatine exerted significant neuroprotection for dopaminergic neurons against neurotoxic insults induced by serum and glucose deprivation (P < 0.01), 1-methyl-4-phenyl pyridinium ion (MPP+) [15 microM] and 6-hydroxydopamine (6-OHDA) [90 microM] exposure (P < 0.01). In addition, creatine treatment significantly protected dopaminergic cells facing MPP+-induced deterioration of neuronal morphology including overall process length/neuron (by 60%), number of branching points/neuron (by 80%) and area of influence per individual neuron (by 60%). Less pronounced effects on overall process length/neuron and number of branching points/neuron were also found after 6-OHDA exposure (P < 0.05) and serum/glucose deprivation (P < 0.05). In conclusion, our findings identify creatine as a rather potent natural survival- and neuroprotective factor for developing nigral dopaminergic neurons, which is of relevance for therapeutic approaches in Parkinson's disease and for the improvement of cell replacement strategies.
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Affiliation(s)
- R H Andres
- Department of Neurosurgery, University Hospital, CH-3010 Berne, Switzerland
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30
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Braegger CP, Schlattner U, Wallimann T, Utiger A, Frank F, Schaefer B, Heizmann CW, Sennhauser FH. Effects of creatine supplementation in cystic fibrosis: results of a pilot study. J Cyst Fibros 2003; 2:177-82. [PMID: 15463870 DOI: 10.1016/s1569-1993(03)00089-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2002] [Accepted: 07/28/2003] [Indexed: 01/31/2023]
Abstract
BACKGROUND The CF transmembrane conductance regulator (CFTR), whose mutations cause cystic fibrosis (CF), depends on ATP for activation and transport function. Availability of ATP in the cell and even more in specific cellular microcompartments often depends on a functional creatine kinase system, which provides the 'energy buffer' phosphocreatine. Creatine supplementation has been shown to increase phosphocreatine levels, thus promoting muscle growth and strength in athletes and having protective effects in neuromuscular disorders. AIM To test clinically, if creatine supplementation improves maximal isometric muscle strength (MIMS), lung function and CFTR channel activity in patients with CF, and to determine enzymatic activity of creatine kinase in respiratory epithelial cells. METHODS In an open-label pilot study 18 CF patients (8-18-year-old) with pancreatic insufficiency and mild to moderate lung disease received daily creatine supplementation during 12 weeks. Patients were monitored during 24-36 weeks. Enzymatic activity of creatine kinase was measured in primary epithelial cell cultures. RESULTS After creatine supplementation, there was no change in lung function and sweat electrolyte concentrations, possibly due to the very low creatine kinase activities detected in respiratory epithelia. However, the patients consistently showed significantly increased MIMS (18.4%; P < 0.0001), as well as improved general well-being, as assessed by a standardized questionnaire. Except for one patient with transient muscle pain, no side effects were reported. CONCLUSIONS Our pilot study suggests, that creatine supplementation should be further evaluated as a possible clinically beneficial adjuvant therapy for patients with CF to increase muscle strength, body-weight and well-being.
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Affiliation(s)
- Christian P Braegger
- Divisions of Gastroenterology and Nutrition and Clinical Chemistry and Biochemistry, University Children's Hospital, Steinwiesstrasse 75, Zürich CH-8032, Switzerland.
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Courtois-Coutry N, Le Moellic C, Boulkroun S, Fay M, Cluzeaud F, Escoubet B, Farman N, Blot-Chabaud M. Calcyclin is an early vasopressin-induced gene in the renal collecting duct. Role in the long term regulation of ion transport. J Biol Chem 2002; 277:25728-34. [PMID: 12000747 DOI: 10.1074/jbc.m112435200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Long-term effects of arginine vasopressin (AVP) in the kidney involve the transcription of unidentified genes. By subtractive hybridization experiments performed on the RCCD(1) cortical collecting duct cell line, we identified calcyclin as an early AVP-induced gene (1 h). Calcyclin is a calcium-binding protein involved in the transduction of intracellular signals. In the kidney, calcyclin was localized at the mRNA level in the glomerulus, all along the collecting duct, and in the epithelium lining the papilla. In RCCD(1) cells and in m-IMCD(3) inner medullary collecting duct cells, calcyclin was evidenced in the cytoplasm. Calcyclin mRNA levels were progressively increased by AVP treatment in RCCD(1) (1.7-fold at 4 h) and m-IMCD(3) (2-fold at 7.5 h) cells. In RCCD(1) cells, calcyclin protein levels were increased by 4 h of AVP treatment. In vivo, treatment of genetically vasopressin-deficient Brattleboro rats with AVP for 4 days induced an increase in both calcyclin and aquaporin-2 mRNA expression. Finally, introduction of anti-calcyclin antibodies into RCCD(1) cells by permeabilizing the plasma membrane prevented the long-term (but not short-term) increase in short-circuit current induced by AVP. Taken together, these results suggest that calcyclin is an early vasopressin-induced gene that participates in the late phase of the hormone response in transepithelial ion transport.
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Affiliation(s)
- Nathalie Courtois-Coutry
- INSERM U478, Institut Fédératif de Recherches 02, Faculté de Médecine Xavier Bichat, Université Paris 7, 16 rue Henri Huchard, France
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32
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Abstract
Phosphagens are phosphorylated guanidino compounds that are linked to energy state and ATP hydrolysis by corresponding phosphagen kinase reactions: phosphagen + MgADP + H(+) <--> guanidine acceptor + MgATP. Eight different phosphagens (and corresponding phosphagen kinases) are found in the animal kingdom distributed along distinct phylogenetic lines. By far, the creatine phosphate/creatine kinase (CP/CK) system, which is found in the vertebrates and is widely distributed throughout the lower chordates and invertebrates, is the most extensively studied phosphagen system. Phosphagen kinase reactions function in temporal ATP buffering, in regulating inorganic phosphate (Pi) levels, which impacts glycogenolysis and proton buffering, and in intracellular energy transport. Phosphagen kinase reactions show differences in thermodynamic poise, and the phosphagens themselves differ in terms of certain physical properties including intrinsic diffusivity. This review evaluates the distribution of phosphagen systems and tissue-specific expression of certain phosphagens in an evolutionary and functional context. The role of phosphagens in regulation of intracellular Pi levels likely evolved early. Thermodynamic poise of the phosphagen kinase reaction profoundly impacts this capacity. Furthermore, it is hypothesized that the capacity for intracellular targeting of CK evolved early as a means of facilitating energy transport in highly polarized cells and was subsequently exploited for temporal ATP buffering and dynamic roles in metabolic regulation in cells displaying high and variable rates of aerobic energy production.
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Affiliation(s)
- W R Ellington
- Department of Biological Science and Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306-4370, USA.
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Rajeswaran WG, Hocart SJ, Murphy WA, Taylor JE, Coy DH. Highly potent and subtype selective ligands derived by N-methyl scan of a somatostatin antagonist. J Med Chem 2001; 44:1305-11. [PMID: 11312929 DOI: 10.1021/jm0005048] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The search for synthetic peptide analogues of somatostatin (SRIF) which exhibit selective affinities for the five known receptor subtypes (sst1-5) has generated a large number of potent agonists. Some of these agonists display good subtype selectivities and affinities for the subtypes 1, 2, 3, and 5, including analogues created by N-methyl amino acid substitutions in a standard octapeptide analogue format. We have now extended this peptide backbone N-methylation approach to a potent somatostatin receptor antagonist series using the antagonist Cpa-cyclo(DCys-Pal-DTrp-Lys-Thr-Cys)-Nal-NH2 9 reported from this laboratory as the lead structure. Synthetic analogues were tested for their ability to inhibit somatostatin-stimulated GH release from rat pituitary cells in culture and to displace 125I-labeled somatostatin from CHO cells transfected with the five known human somatostatin receptors. Several interesting observations resulted from the study. N-Methylation at the Lys(9) residue (5) increased the rat GH release inhibitory potency nearly 4-fold to 0.73 nM but resulted in little change in the binding affinity for human type 2 receptor. This analogue also had a high affinity of 5.98 nM for sst5 receptor (compared to 1.4 nM for somatostatin itself) and is the first antagonist analogue to be reported with high affinity for sst5. It also had high potency on in vitro inhibition of sst5 mediated intracellular calcium mobilization. These results were considered surprising, since the Lys(9) residue has long been considered to constitute the active center of somatostatin, important both for receptor binding and activation, and suggests important conformational differences between D-Cys(9) somatostatin antagonists and normal agonist structures. More modifications were carried out on this analogue with the aim of improving antagonist potency and/or specificity. Tyr(7) substitution of 5 resulted in an analogue, which had the highest affinity in the series for hsst2 (K(I) 5.51 nM) and an extraordinarily low IC50 of 0.53 nM in the rat pituitary cell assay. However, this analogue lost considerable affinity for sst5 relative to analogue 5. Analogue 16 with DTrp(12) at C-terminus had the highest affinity for hsst2, however, the IC50 in the rat GH release assay was only 11.6 nM. Replacement of Lys(9) in 9 with Dab(9) gave 11 which displayed high binding affinity for sst3, and it was also quite selective for that receptor. Both the sst3 and sst5 antagonists should be of value in assigning the physiological roles to type 3 and 5 receptor, respectively.
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Affiliation(s)
- W G Rajeswaran
- Peptide Research Labs, SL 12, Department of Medicine, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, Louisiana 70112, USA
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Gonçalves CA, Gottfried C, Dunkley PR. The use of permeabilized cells to assay protein phosphorylation and catecholamine release. Neurochem Res 2000; 25:885-94. [PMID: 10944008 DOI: 10.1023/a:1007533927813] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A number of approaches can be used to determine the protein kinases and protein phosphatases acting on particular phosphoproteins in vivo. Cell permeabilization represents one such approach. In this overview we discuss the different permeabilization procedures used in bovine adrenal chromaffin cells and in particular the use of digitonin. The effect of various factors on the extent of digitonin-permeabilization, protein phosphorylation and catecholamine release are also discussed. The factors include the permeabilization medium, the ions such as calcium, and the second messengers, such as cAMP, IP3, cADPR and calmodulin. The effect of specific peptide inhibitors of protein kinases on tyrosine hydroxylase phosphorylation is illustrated. Advantages and disadvantages of cell permeabilization procedures are discussed throughout the text.
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Affiliation(s)
- C A Gonçalves
- Dept de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Brazil
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Eder M, Schlattner U, Becker A, Wallimann T, Kabsch W, Fritz-Wolf K. Crystal structure of brain-type creatine kinase at 1.41 A resolution. Protein Sci 1999; 8:2258-69. [PMID: 10595529 PMCID: PMC2144193 DOI: 10.1110/ps.8.11.2258] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Excitable cells and tissues like muscle or brain show a highly fluctuating consumption of ATP, which is efficiently regenerated from a large pool of phosphocreatine by the enzyme creatine kinase (CK). The enzyme exists in tissue--as well as compartment-specific isoforms. Numerous pathologies are related to the CK system: CK is found to be overexpressed in a wide range of solid tumors, whereas functional impairment of CK leads to a deterioration in energy metabolism, which is phenotypic for many neurodegenerative and age-related diseases. The crystal structure of chicken cytosolic brain-type creatine kinase (BB-CK) has been solved to 1.41 A resolution by molecular replacement. It represents the most accurately determined structure in the family of guanidino kinases. Except for the N-terminal region (2-12), the structures of both monomers in the biological dimer are very similar and closely resemble those of the other known structures in the family. Specific Ca2+-mediated interactions, found between two dimers in the asymmetric unit, result in structurally independent heterodimers differing in their N-terminal conformation and secondary structure. The high-resolution structure of BB-CK presented in this work will assist in designing new experiments to reveal the molecular basis of the multiple isoform-specific properties of CK, especially regarding different subcellular locations and functional interactions with other proteins. The rather similar fold shared by all known guanidino kinase structures suggests a model for the transition state complex of BB-CK analogous to the one of arginine kinase (AK). Accordingly, we have modeled a putative conformation of CK in the transition state that requires a rigid body movement of the entire N-terminal domain by rms 4 A from the structure without substrates.
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Affiliation(s)
- M Eder
- Institute of Cell Biology, Swiss Federal Institute of Technology, ETH Zurich, Switzerland
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