1
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Castaldo G, Marino C, Atteno M, D’Elia M, Pagano I, Grimaldi M, Conte A, Molettieri P, Santoro A, Napolitano E, Puca I, Raimondo M, Parisella C, D’Ursi AM, Rastrelli L. Investigating the Effectiveness of a Carb-Free Oloproteic Diet in Fibromyalgia Treatment. Nutrients 2024; 16:1620. [PMID: 38892552 PMCID: PMC11175073 DOI: 10.3390/nu16111620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/15/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
Fibromyalgia (FM), a chronic disease with a high incidence in women, poses a significant challenge for diagnosis and treatment, especially due to the absence of specific biomarkers and the multifaceted nature of its symptoms, which range from neuromuscular pain to mood disorders and intestinal dysbiosis. While diagnosis currently relies on rheumatological clinical evaluations and treatment options mainly focus on symptom management, FM seems to have possible links with systemic metabolic dysfunctions with a common inflammatory root. In this context, a new therapeutic avenue emerges: could a therapeutic nutritional approach be the missing piece of the puzzle? Indeed, diet therapies employed particularly for metabolic syndromes proved recently to be efficacious for correcting systemic dysmetabolism and a high number of chronic inflammation conditions. In particular, the very-low-calorie ketogenic diet (VLCKD) demonstrated therapeutic benefits in many disorders. In the present study, we aimed to investigate the specific effects of two dietary interventions, namely the oloproteic VLCKD and the low-glycemic insulinemic (LOGI) diet, on two groups of female FM patients (FM1 and FM2) over a 45-day period. Utilizing clinical and laboratory tests, as well as non-invasive NMR metabolomic analysis of serum, urine, and saliva samples, we sought to uncover how these dietary regimens impact the metabolic dysfunctions associated with FM.
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Affiliation(s)
- Giuseppe Castaldo
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Carmen Marino
- PhD Program in Drug Discovery and Development, Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (C.M.); (E.N.)
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (M.G.); (A.S.)
| | - Mariangela Atteno
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Maria D’Elia
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy;
- Department of Pharmacy, Scuola di Specializzazione in Farmacia Ospedaliera, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy
| | - Imma Pagano
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Manuela Grimaldi
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (M.G.); (A.S.)
| | - Aurelio Conte
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Paola Molettieri
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Angelo Santoro
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (M.G.); (A.S.)
- Department of Pharmacy, Scuola di Specializzazione in Farmacia Ospedaliera, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy
| | - Enza Napolitano
- PhD Program in Drug Discovery and Development, Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (C.M.); (E.N.)
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (M.G.); (A.S.)
| | - Ilaria Puca
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Mariangela Raimondo
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Chiara Parisella
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
| | - Anna Maria D’Ursi
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy; (M.G.); (A.S.)
| | - Luca Rastrelli
- NutriKeto_LAB Unisa—“San Giuseppe Moscati” National Hospital (AORN), Contrada Amoretta, 83100 Avellino, Italy (M.A.); (I.P.); (A.C.); (P.M.); (I.P.); (M.R.); (C.P.)
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy;
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2
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Bian X, Zhu J, Jia X, Liang W, Yu S, Li Z, Zhang W, Rao Y. Suggestion of creatine as a new neurotransmitter by approaches ranging from chemical analysis and biochemistry to electrophysiology. eLife 2023; 12:RP89317. [PMID: 38126335 PMCID: PMC10735228 DOI: 10.7554/elife.89317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023] Open
Abstract
The discovery of a new neurotransmitter, especially one in the central nervous system, is both important and difficult. We have been searching for new neurotransmitters for 12 y. We detected creatine (Cr) in synaptic vesicles (SVs) at a level lower than glutamate and gamma-aminobutyric acid but higher than acetylcholine and 5-hydroxytryptamine. SV Cr was reduced in mice lacking either arginine:glycine amidinotransferase (a Cr synthetase) or SLC6A8, a Cr transporter with mutations among the most common causes of intellectual disability in men. Calcium-dependent release of Cr was detected after stimulation in brain slices. Cr release was reduced in Slc6a8 and Agat mutants. Cr inhibited neocortical pyramidal neurons. SLC6A8 was necessary for Cr uptake into synaptosomes. Cr was found by us to be taken up into SVs in an ATP-dependent manner. Our biochemical, chemical, genetic, and electrophysiological results are consistent with the possibility of Cr as a neurotransmitter, though not yet reaching the level of proof for the now classic transmitters. Our novel approach to discover neurotransmitters is to begin with analysis of contents in SVs before defining their function and physiology.
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Affiliation(s)
- Xiling Bian
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
- Chinese Institute for Brain Research (CIBR)BeijingChina
| | - Jiemin Zhu
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
- Chinese Institute for Brain Research (CIBR)BeijingChina
| | - Xiaobo Jia
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
- Chinese Institute for Brain Research (CIBR)BeijingChina
| | - Wenjun Liang
- Chinese Institutes of Medical Research, Capital Medical UniversityBeijingChina
- Changping Laboratory, Yard 28, Science Park Road, Changping DistrictBeijingChina
| | - Sihan Yu
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
- Changping Laboratory, Yard 28, Science Park Road, Changping DistrictBeijingChina
| | - Zhiqiang Li
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
| | - Wenxia Zhang
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
- Chinese Institutes of Medical Research, Capital Medical UniversityBeijingChina
- Institute of Molecular Physiology, Shenzhen Bay LaboratoryShenzhenChina
| | - Yi Rao
- Laboratory of Neurochemical Biology, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking UniversityBeijingChina
- Chinese Institute for Brain Research (CIBR)BeijingChina
- Chinese Institutes of Medical Research, Capital Medical UniversityBeijingChina
- Changping Laboratory, Yard 28, Science Park Road, Changping DistrictBeijingChina
- Institute of Molecular Physiology, Shenzhen Bay LaboratoryShenzhenChina
- Research Unit of Medical Neurobiology, Chinese Academy of Medical SciencesBeijingChina
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3
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Meera P, Uusi-Oukari M, Wallner M, Lipshutz GS. Guanidinoacetate (GAA) is a potent GABA A receptor GABA mimetic: Implications for neurological disease pathology. J Neurochem 2023; 165:445-454. [PMID: 36726215 DOI: 10.1111/jnc.15774] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/24/2023] [Accepted: 01/28/2023] [Indexed: 02/03/2023]
Abstract
Impairment of excretion and enzymatic processing of nitrogen, for example, because of liver or kidney failure, or with urea cycle and creatine synthesis enzyme defects, surprisingly leads to primarily neurologic symptoms, yet the exact mechanisms remain largely mysterious. In guanidinoacetate N-methyltransferase (GAMT) deficiency, the guanidino compound guanidinoacetate (GAA) increases dramatically, including in the cerebrospinal fluid (CSF), and has been implicated in mediating the neurological symptoms in GAMT-deficient patients. GAA is synthesized by arginine-glycine amidinotransferase (AGAT), a promiscuous enzyme that not only transfers the amidino group from arginine to glycine, but also to primary amines in, for example, GABA and taurine to generate γ-guanidinobutyric acid (γ-GBA) and guanidinoethanesulfonic acid (GES), respectively. We show that GAA, γ-GBA, and GES share structural similarities with GABA, evoke GABAA receptor (GABAA R) mediated currents (whereas creatine [methylated GAA] and arginine failed to evoke discernible currents) in cerebellar granule cells in mouse brain slices and displace the high-affinity GABA-site radioligand [3 H]muscimol in total brain homogenate GABAA Rs. While γ-GBA and GES are GABA agonists and displace [3 H]muscimol (EC50 /IC50 between 10 and 40 μM), GAA stands out as particularly potent in both activating GABAA Rs (EC50 ~6 μM) and also displacing the GABAA R ligand [3 H]muscimol (IC50 ~3 μM) at pathophysiologically relevant concentrations. These findings stress the role of substantially elevated GAA as a primary neurotoxic agent in GAMT deficiency and we discuss the potential role of GAA in arginase (and creatine transporter) deficiency which show a much more modest increase in GAA concentrations yet share the unique hyperexcitability neuropathology with GAMT deficiency. We conclude that orthosteric activation of GABAA Rs by GAA, and potentially other GABAA R mimetic guanidino compounds (GCs) like γ-GBA and GES, interferes with normal inhibitory GABAergic neurotransmission which could mediate, and contribute to, neurotoxicity.
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Affiliation(s)
- Pratap Meera
- Department of Neurobiology, University of California, Los Angeles, California, USA
| | - Mikko Uusi-Oukari
- Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, Turku, Finland
| | - Martin Wallner
- Departments of Surgery, University of California, Los Angeles, California, USA
| | - Gerald S Lipshutz
- Departments of Surgery, University of California, Los Angeles, California, USA.,Molecular & Medical Pharmacology, University of California, Los Angeles, California, USA.,Intellectual and Developmental Disabilities Research Center, University of California, Los Angeles, California, USA.,Semel Institute for Neuroscience, University of California, Los Angeles, California, USA
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4
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Aghamollaii V, Meshkat S, Bakhtiari S, Alehabib E, Firouzabadi SG, Molaei S, Kruer MC, Darvish H. Guanidinoacetate Methyltransferase Deficiency, a Treatable Neurodevelopmental Disorder. JOURNAL OF PEDIATRIC EPILEPSY 2023. [DOI: 10.1055/s-0042-1760291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
AbstractGuanidinoacetate methyltransferase (GAMT) deficiency is an autosomal recessive inborn error of creatine synthesis that results in intellectual disability, epilepsy, expressive language delay, and dystonia. We report data from two siblings with an uncommon GAMT deficiency phenotype and their clinical, biochemical, imaging, and treatment findings. The older sibling had intellectual disability, epilepsy, and generalized dystonia. The younger sibling had intellectual disability and generalized dystonia. After treatment with creatine, verbal fluency improved, as well as dystonia and aggression. This study confirms that in patients with unexplained intellectual disability, epilepsy, and/or movement disorders, GAMT deficiency should be considered. GAMT-associated cerebral creatine deficiency syndrome is a potentially treatable condition and can be identified by elevated levels of guanidinoacetate in plasma or urine or by a significantly decreased creatine peak on magnetic resonance spectroscopy.
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Affiliation(s)
- Vajiheh Aghamollaii
- Neurology Department, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Shakila Meshkat
- Neurology Department, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Somayeh Bakhtiari
- Barrow Neurological Institute, Phoenix Children's Hospital, University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, United States
| | - Elham Alehabib
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Samira Molaei
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Michael C. Kruer
- Barrow Neurological Institute, Phoenix Children's Hospital, University of Arizona College of Medicine – Phoenix, Phoenix, Arizona, United States
| | - Hossein Darvish
- Cancer Research Center, Department of Medical Genetics, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
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5
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Almaghrabi MA, Muthaffar OY, Alahmadi SA, Abdulsbhan MA, Bamusa M, Aljezani MA, Bahowarth SY, Alyazidi AS, Aggad WS. GAMT Deficiency Among Pediatric Population: Clinical and Molecular Characteristics and Management. Child Neurol Open 2023; 10:2329048X231215630. [PMID: 38020815 PMCID: PMC10655665 DOI: 10.1177/2329048x231215630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/12/2023] [Accepted: 11/03/2023] [Indexed: 12/01/2023] Open
Abstract
Objective: Analyze the treatment modalities used in real practice by synthesizing available literature. Methods: We reviewed and evaluated 52 cases of GAMT deficiency including 4 novel cases from Saudi Arabia diagnosed using whole-exome sequencing. All data utilized graphical presentation in the form of line charts and illustrated graphs. Results: The mean current age of was 117 months (±29.03) (range 12-372 months). The mean age of disease onset was 28.32 months (±13.68) (range 8 days - 252 months). The most prevalent symptom was developmental delays, mainly speech and motor, seizures, and intellectual disability. The male-to-female ratio was 3:1. Multiple treatments were used, with 54 pharmacological interventions, valproic acid being the most common. Creatinine monohydrate was the prevalent dietary intervention, with 25 patients reporting an improvement. Conclusion: The study suggests that efficient treatment with appropriate dietary intervention can improve patients' health, stressing that personalized treatment programs are essential in managing this disorder.
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Affiliation(s)
- Majdah A. Almaghrabi
- Division of Pediatrics Neurology, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Osama Y. Muthaffar
- Division of Pediatrics Neurology, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sereen A. Alahmadi
- Division of Pediatrics Neurology, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mashael A. Abdulsbhan
- Division of Pediatrics Neurology, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mashael Bamusa
- Division of Pediatrics Neurology, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Maram Ahmed Aljezani
- Division of Pediatrics Neurology, Department of Pediatrics, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Anas S. Alyazidi
- Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Waheeb S. Aggad
- Department of Anatomy, Faculty of Medicine, University of Jeddah, Jeddah, Saudi Arabia
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6
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Khoja S, Lambert J, Nitzahn M, Eliav A, Zhang Y, Tamboline M, Le CT, Nasser E, Li Y, Patel P, Zhuravka I, Lueptow LM, Tkachyova I, Xu S, Nissim I, Schulze A, Lipshutz GS. Gene therapy for guanidinoacetate methyltransferase deficiency restores cerebral and myocardial creatine while resolving behavioral abnormalities. Mol Ther Methods Clin Dev 2022; 25:278-296. [PMID: 35505663 PMCID: PMC9051621 DOI: 10.1016/j.omtm.2022.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 03/27/2022] [Indexed: 11/06/2022]
Abstract
Creatine deficiency disorders are inborn errors of creatine metabolism, an energy homeostasis molecule. One of these, guanidinoacetate N-methyltransferase (GAMT) deficiency, has clinical characteristics that include features of autism, self-mutilation, intellectual disability, and seizures, with approximately 40% having a disorder of movement; failure to thrive can also be a component. Along with low creatine levels, guanidinoacetic acid (GAA) toxicity has been implicated in the pathophysiology of the disorder. Present-day therapy with oral creatine to control GAA lacks efficacy; seizures can persist. Dietary management and pharmacological ornithine treatment are challenging. Using an AAV-based gene therapy approach to express human codon-optimized GAMT in hepatocytes, in situ hybridization, and immunostaining, we demonstrated pan-hepatic GAMT expression. Serial collection of blood demonstrated a marked early and sustained reduction of GAA with normalization of plasma creatine; urinary GAA levels also markedly declined. The terminal time point demonstrated marked improvement in cerebral and myocardial creatine levels. In conjunction with the biochemical findings, treated mice gained weight to nearly match their wild-type littermates, while behavioral studies demonstrated resolution of abnormalities; PET-CT imaging demonstrated improvement in brain metabolism. In conclusion, a gene therapy approach can result in long-term normalization of GAA with increased creatine in guanidinoacetate N-methyltransferase deficiency and at the same time resolves the behavioral phenotype in a murine model of the disorder. These findings have important implications for the development of a new therapy for this abnormality of creatine metabolism.
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Affiliation(s)
- Suhail Khoja
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA
| | - Jenna Lambert
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA
| | - Matthew Nitzahn
- Molecular Biology Institute, UCLA, Los Angeles, CA 90025, USA
| | - Adam Eliav
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA
| | - YuChen Zhang
- Semel Institute for Neuroscience, UCLA, Los Angeles, CA 90025, USA
| | - Mikayla Tamboline
- Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA 90025, USA.,Departments of Molecular and Medical Pharmacology, Universtiy of California, Los Angeles, CA 90025, USA
| | - Colleen T Le
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA
| | - Eram Nasser
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA
| | - Yunfeng Li
- Departments of Pathology and Laboratory Medicine, UCLA, Los Angeles, CA 90025, USA
| | - Puja Patel
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA
| | - Irina Zhuravka
- Behavioral Testing Core, Department of Psychology, UCLA, Los Angeles, CA 90025, USA
| | - Lindsay M Lueptow
- Behavioral Testing Core, Department of Psychology, UCLA, Los Angeles, CA 90025, USA
| | - Ilona Tkachyova
- Research Institute, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Shili Xu
- Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA 90025, USA.,Departments of Molecular and Medical Pharmacology, Universtiy of California, Los Angeles, CA 90025, USA.,Jonsson Comprehensive Cancer Center at UCLA, David Geffen School of Medicine at UCLA, Los Angeles, CA 90025, USA
| | - Itzhak Nissim
- Division of Metabolism and Human Genetics, Children's Hospital of Philadelphia, and the Department of Biochemistry and Biophysics, Perlman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Andreas Schulze
- Department of Paediatrics, University of Toronto, Toronto, ON M5G 1X8, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON M5G 1X8, Canada.,Research Institute, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Gerald S Lipshutz
- Department of Surgery, UCLA, Los Angeles, CA 90025, USA.,Molecular Biology Institute, UCLA, Los Angeles, CA 90025, USA.,Semel Institute for Neuroscience, UCLA, Los Angeles, CA 90025, USA.,Departments of Molecular and Medical Pharmacology, Universtiy of California, Los Angeles, CA 90025, USA.,Intellectual and Developmental Disabilities Research Center, UCLA, Los Angeles, CA 90025, USA
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7
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Dentel B, Angeles-Perez L, Ren C, Jakkamsetti V, Holley AJ, Caballero D, Oh E, Gibson J, Pascual JM, Huber KM, Tu BP, Tsai PT. Increased glycine contributes to synaptic dysfunction and early mortality in Nprl2 seizure model. iScience 2022; 25:104334. [PMID: 35602938 PMCID: PMC9118754 DOI: 10.1016/j.isci.2022.104334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 09/16/2021] [Accepted: 04/26/2022] [Indexed: 10/25/2022] Open
Abstract
Targeted therapies for epilepsies associated with the mTORC1 signaling negative regulator GATOR1 are lacking. NPRL2 is a subunit of the GATOR1 complex and mutations in GATOR1 subunits, including NPRL2, are associated with epilepsy. To delineate the mechanisms underlying NPRL2-related epilepsies, we created a mouse (Mus musculus) model with neocortical loss of Nprl2. Mutant mice have increased mTORC1 signaling and exhibit spontaneous seizures. They also display abnormal synaptic function characterized by increased evoked and spontaneous EPSC and decreased evoked and spontaneous IPSC frequencies, respectively. Proteomic and metabolomics studies of Nprl2 mutants revealed alterations in known epilepsy-implicated proteins and metabolic pathways, including increases in the neurotransmitter, glycine. Furthermore, glycine actions on the NMDA receptor contribute to the electrophysiological and survival phenotypes of these mice. Taken together, in this neuronal Nprl2 model, we delineate underlying molecular, metabolic, and electrophysiological mechanisms contributing to mTORC1-related epilepsy, providing potential therapeutic targets for epilepsy.
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Affiliation(s)
- Brianne Dentel
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | | | - Chongyu Ren
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Vikram Jakkamsetti
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Andrew J. Holley
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Daniel Caballero
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Emily Oh
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Jay Gibson
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Juan M. Pascual
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Kimberly M. Huber
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Benjamin P. Tu
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Peter T. Tsai
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
- Departments of Pediatrics and Psychiatry, UT Southwestern Medical Center, Dallas, TX 75235, USA
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8
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Ostojic SM. Guanidinoacetic Acid as a Nutritional Adjuvant to Multiple Sclerosis Therapy. Front Hum Neurosci 2022; 16:871535. [PMID: 35634212 PMCID: PMC9134824 DOI: 10.3389/fnhum.2022.871535] [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: 02/08/2022] [Accepted: 04/11/2022] [Indexed: 11/13/2022] Open
Abstract
Tackling impaired bioenergetics in multiple sclerosis (MS) has been recently recognized as an innovative approach with therapeutic potential. Guanidinoacetic acid (GAA) is an experimental nutrient that plays a significant role in high-energy phosphate metabolism. The preliminary trials suggest beneficial effects of supplemental GAA in MS, with GAA augments biomarkers of brain energy metabolism and improves patient-reported features of the disease. GAA can also impact other metabolic footprints of MS, including demyelination, oxidative stress, and GABA-glutamate imbalance. In this mini-review article, we summarize studies evaluating GAA effectiveness in MS, explore mechanisms of GAA action, and discuss the challenges of using dietary GAA as an element of MS therapy.
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Affiliation(s)
- Sergej M. Ostojic
- Department of Nutrition and Public Health, University of Agder, Kristiansand, Norway
- Faculty of Sport and Physical Education (FSPE) Applied Bioenergetics Lab, University of Novi Sad, Novi Sad, Serbia
- Faculty of Health Sciences, University of Pécs, Pécs, Hungary
- *Correspondence: Sergej M. Ostojic,
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9
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Elsaid S, Rubin-Kahana DS, Kloiber S, Kennedy SH, Chavez S, Le Foll B. Neurochemical Alterations in Social Anxiety Disorder (SAD): A Systematic Review of Proton Magnetic Resonance Spectroscopic Studies. Int J Mol Sci 2022; 23:ijms23094754. [PMID: 35563145 PMCID: PMC9105768 DOI: 10.3390/ijms23094754] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/18/2022] [Accepted: 04/18/2022] [Indexed: 12/10/2022] Open
Abstract
(1) Objective: Considering that current knowledge of mechanisms involved in the molecular pathogenesis of Social Anxiety Disorder (SAD) is limited, we conducted a systematic review to evaluate cumulative data obtained by Proton Magnetic Resonance Spectroscopic (1H MRS) studies. (2) Methods: A computer-based literature search of Medline, EMBASE, PsycInfo, and ProQuest was performed. Only cross-sectional studies using 1H MRS techniques in participants with SAD and healthy controls (HCs) were selected. (3) Results: The search generated eight studies. The results indicated regional abnormalities in the ‘fear neurocircuitry’ in patients with SAD. The implicated regions included the anterior cingulate cortex (ACC), dorsomedial prefrontal cortex (dmPFC), dorsolateral prefrontal cortex (dlPFC), insula, occipital cortex (OC), as well as the subcortical regions, including the thalamus, caudate, and the putamen. (4) Conclusions: The evidence derived from eight studies suggests that possible pathophysiological mechanisms of SAD include impairments in the integrity and function of neurons and glial cells, including disturbances in energy metabolism, maintenance of phospholipid membranes, dysregulations of second messenger systems, and excitatory/inhibitory neurocircuitry. Conducting more cross-sectional studies with larger sample sizes is warranted given the limited evidence in this area of research.
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Affiliation(s)
- Sonja Elsaid
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1, Canada; (S.E.); (D.S.R.-K.)
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; (S.K.); (S.H.K.); (S.C.)
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
| | - Dafna S. Rubin-Kahana
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1, Canada; (S.E.); (D.S.R.-K.)
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
| | - Stefan Kloiber
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; (S.K.); (S.H.K.); (S.C.)
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Sidney H. Kennedy
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; (S.K.); (S.H.K.); (S.C.)
- Centre for Depression and Suicide Studies, Unity Health Toronto, Toronto, ON M5B 1M4, Canada
- Li Ka Shing Knowledge Institute, Toronto, ON M5B 1T8, Canada
- Krembil Research Institute, University Health Network, Toronto, ON M5T 0S8, Canada
- Homewood Research Institute, Guelph, ON N1E 6K9, Canada
| | - Sofia Chavez
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; (S.K.); (S.H.K.); (S.C.)
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1, Canada; (S.E.); (D.S.R.-K.)
- Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; (S.K.); (S.H.K.); (S.C.)
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Departments of Family and Community Medicine, University of Toronto, Toronto, ON M5T 1R8, Canada
- Addictions Division, Centre for Addiction and Mental Health, Toronto, ON M6J 1H3, Canada
- Waypoint Research Institute, Waypoint Centre for Mental Health Care, Penetanguishene, ON L9M 1G3, Canada
- Correspondence: ; Tel.: +1-416-535-8501 (ext. 33111)
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10
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Jomura R, Akanuma SI, Tachikawa M, Hosoya KI. SLC6A and SLC16A family of transporters: Contribution to transport of creatine and creatine precursors in creatine biosynthesis and distribution. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183840. [PMID: 34921896 DOI: 10.1016/j.bbamem.2021.183840] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/06/2021] [Accepted: 12/09/2021] [Indexed: 11/16/2022]
Abstract
Creatine (Cr) is needed to maintain high energy levels in cells. Since Cr plays reportedly a critical role in neurodevelopment and the immune system, Cr dynamics should be strictly regulated to control these physiological events. This review focuses on the role of transporters that recognize Cr and/or Cr precursors. Our previous studies revealed physiological roles of SLC6A and SLC16A family transporters in Cr dynamics. Creatine transporter (CRT/SLC6A8) contributes to the influx transport of Cr in Cr distribution. γ-Aminobutyric acid transporter 2 (GAT2/SLC6A13) mediates incorporation of guanidinoacetate (GAA), a Cr precursor, in the process of Cr biosynthesis. Monocarboxylate transporter 12 (MCT12/SLC16A12) functions as an efflux transporter for Cr and GAA, and contributes to the process of Cr biosynthesis. Accordingly, the SLC6A and SLC16A family of transporters play important roles in the process of Cr biosynthesis and distribution via permeation of Cr and Cr precursors across the plasma membrane.
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Affiliation(s)
- Ryuta Jomura
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
| | - Shin-Ichi Akanuma
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
| | - Masanori Tachikawa
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan.
| | - Ken-Ichi Hosoya
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
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11
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Effects of Creatine Supplementation on Brain Function and Health. Nutrients 2022; 14:nu14050921. [PMID: 35267907 PMCID: PMC8912287 DOI: 10.3390/nu14050921] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 02/06/2023] Open
Abstract
While the vast majority of research involving creatine supplementation has focused on skeletal muscle, there is a small body of accumulating research that has focused on creatine and the brain. Preliminary studies indicate that creatine supplementation (and guanidinoacetic acid; GAA) has the ability to increase brain creatine content in humans. Furthermore, creatine has shown some promise for attenuating symptoms of concussion, mild traumatic brain injury and depression but its effect on neurodegenerative diseases appears to be lacking. The purpose of this narrative review is to summarize the current body of research pertaining to creatine supplementation on total creatine and phophorylcreatine (PCr) content, explore GAA as an alternative or adjunct to creatine supplementation on brain creatine uptake, assess the impact of creatine on cognition with a focus on sleep deprivation, discuss the effects of creatine supplementation on a variety of neurological and mental health conditions, and outline recent advances on creatine supplementation as a neuroprotective supplement following traumatic brain injury or concussion.
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12
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Fernandes-Pires G, Braissant O. Current and potential new treatment strategies for creatine deficiency syndromes. Mol Genet Metab 2022; 135:15-26. [PMID: 34972654 DOI: 10.1016/j.ymgme.2021.12.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/14/2021] [Accepted: 12/14/2021] [Indexed: 12/16/2022]
Abstract
Creatine deficiency syndromes (CDS) are inherited metabolic disorders caused by mutations in GATM, GAMT and SLC6A8 and mainly affect central nervous system (CNS). AGAT- and GAMT-deficient patients lack the functional brain endogenous creatine (Cr) synthesis pathway but express the Cr transporter SLC6A8 at blood-brain barrier (BBB), and can thus be treated by oral supplementation of high doses of Cr. For Cr transporter deficiency (SLC6A8 deficiency or CTD), current treatment strategies benefit one-third of patients. However, as their phenotype is not completely reversed, and for the other two-thirds of CTD patients, the development of novel more effective therapies is needed. This article aims to review the current knowledge on Cr metabolism and CDS clinical aspects, highlighting their current treatment possibilities and the most recent research perspectives on CDS potential therapeutics designed, in particular, to bring new options for the treatment of CTD.
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Affiliation(s)
- Gabriella Fernandes-Pires
- Service of Clinical Chemistry, University of Lausanne and Lausanne University Hospital, Lausanne, Switzerland
| | - Olivier Braissant
- Service of Clinical Chemistry, University of Lausanne and Lausanne University Hospital, Lausanne, Switzerland.
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13
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Ostojic SM. Safety of Dietary Guanidinoacetic Acid: A Villain of a Good Guy? Nutrients 2021; 14:nu14010075. [PMID: 35010949 PMCID: PMC8746922 DOI: 10.3390/nu14010075] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/18/2021] [Accepted: 12/23/2021] [Indexed: 12/19/2022] Open
Abstract
Guanidinoacetic acid (GAA) is a natural amino acid derivative that is well-recognized for its central role in the biosynthesis of creatine, an essential compound involved in cellular energy metabolism. GAA (also known as glycocyamine or betacyamine) has been investigated as an energy-boosting dietary supplement in humans for more than 70 years. GAA is suggested to effectively increase low levels of tissue creatine and improve clinical features of cardiometabolic and neurological diseases, with GAA often outcompeting traditional bioenergetics agents in maintaining ATP status during stress. This perhaps happens due to a favorable delivery of GAA through specific membrane transporters (such as SLC6A6 and SLC6A13), previously dismissed as un-targetable carriers by other therapeutics, including creatine. The promising effects of dietary GAA might be countered by side-effects and possible toxicity. Animal studies reported neurotoxic and pro-oxidant effects of GAA accumulation, with exogenous GAA also appearing to increase methylation demand and circulating homocysteine, implying a possible metabolic burden of GAA intervention. This mini-review summarizes GAA toxicity evidence in human nutrition and outlines functional GAA safety through benefit-risk assessment and multi-criteria decision analysis.
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Affiliation(s)
- Sergej M. Ostojic
- Department of Nutrition and Public Health, University of Agder, 4604 Kristiansand, Norway; ; Tel.: +47-38-14-13-64
- FSPE Applied Bioenergetics Lab, University of Novi Sad, 21000 Novi Sad, Serbia
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14
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Baker SA, Gajera CR, Wawro AM, Corces MR, Montine TJ. GATM and GAMT synthesize creatine locally throughout the mammalian body and within oligodendrocytes of the brain. Brain Res 2021; 1770:147627. [PMID: 34418357 DOI: 10.1016/j.brainres.2021.147627] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 08/08/2021] [Accepted: 08/14/2021] [Indexed: 11/17/2022]
Abstract
The enzymes glycine amidinotransferase, mitochondrial (GATM also known as AGAT) and guanidinoacetate N-methyltransferase (GAMT) function together to synthesize creatine from arginine, glycine, and S-Adenosyl methionine. Deficiency in either enzyme or the creatine transporter, CT1, results in a devastating neurological disorder, Cerebral Creatine Deficiency Syndrome (CCDS). To better understand the pathophysiology of CCDS, we mapped the distribution of GATM and GAMT at single cell resolution, leveraging RNA sequencing analysis combined with in vivo immunofluorescence (IF). Using the mouse as a model system, we find that GATM and GAMT are coexpressed in several tissues with distinct and overlapping cellular sources, implicating local synthesis as an important mechanism of creatine metabolism in numerous organs. Extending previous findings at the RNA level, our analysis demonstrates that oligodendrocytes express the highest level of Gatm and Gamt of any cell type in the body. We confirm this finding in the mouse brain by IF, where GATM localizes to the mitochondria of oligodendrocytes, whereas both oligodendrocytes and cerebral cortical neurons express GAMT. Interestingly, the latter is devoid of GATM. Single nucleus assay for transposase-accessible chromatin sequencing (snATAC-seq) analysis of 4 brain regions highlights a similar primacy of oligodendrocytes in the expression of GATM and GAMT in the human central nervous system. Importantly, an active putative regulatory element within intron 2 of human GATM is detected in oligodendrocytes but not neurons.
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Affiliation(s)
- Steven Andrew Baker
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Chandresh R Gajera
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Adam M Wawro
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - M Ryan Corces
- Gladstone Institute of Neurological Disease, Gladstone Institute of Data Science and Biotechnology, San Francisco, CA 94158, USA; Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Thomas J Montine
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94035, USA; Lead Contact.
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15
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Performance, Carcass Yield, Muscle Amino Acid Profile, and Levels of Brain Neurotransmitters in Aged Laying Hens Fed Diets Supplemented with Guanidinoacetic Acid. Animals (Basel) 2021; 11:ani11113091. [PMID: 34827823 PMCID: PMC8614553 DOI: 10.3390/ani11113091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 10/26/2021] [Indexed: 01/02/2023] Open
Abstract
Guanidinoacetic acid (GA) is a natural precursor of creatine in the body and is usually used to improve the feed conversion and cellular energy metabolism of broiler chickens. The objective was to elucidate the effect of dietary supplementation of GA on carcass yield, muscle amino acid profile, and concentrations of brain neurotransmitters in laying hens. In total, 128 72-week-old ISA Brown laying hens were assigned to four equal groups (32 birds, eight replicates per group). The control group (T1) was fed a basal diet with no supplements, while the other experimental groups were fed a basal diet supplemented with 0.5 (T2), 1.0 (T3), and 1.5 (T4) g GA kg-1 diet. The T3 and T4 groups showed higher hen-day egg production and carcass yield compared to the control group (p = 0.016 and 0.039, respectively). The serum creatine level increased linearly with the increased level of dietary GA (p = 0.007). Among the essential amino acids of breast muscle, a GA-supplemented diet linearly increased the levels of leucine, isoleucine, phenylalanine, methionine, and threonine in the breast (p = 0.003, 0.047, 0.001, 0.001, and 0.015, respectively) and thigh (p = 0.026, 0.001, 0.020, 0.009, and 0.028, respectively) muscles. GA supplementation linearly reduced the level of brain serotonin compared to the control group (p = 0.010). Furthermore, supplementation of GA in the diet of laying hens linearly increased the level of brain dopamine (p = 0.011), but reduced the level of brain Gamma-aminobutyric acid (p = 0.027). Meanwhile, the concentration of brain nitric oxide did not differ between the experimental groups (p = 0.080). In conclusion, the dietary supplementation of GA may improve the carcass yield and levels of essential amino acids in the breast muscles, as well as the brain neurotransmitters in aged laying hens.
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16
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Spitzer SO, Tkacz A, Savignac HM, Cooper M, Giallourou N, Mann EO, Bannerman DM, Swann JR, Anthony DC, Poole PS, Burnet PW. Postnatal prebiotic supplementation in rats affects adult anxious behaviour, hippocampus, electrophysiology, metabolomics, and gut microbiota. iScience 2021; 24:103113. [PMID: 34611610 PMCID: PMC8476651 DOI: 10.1016/j.isci.2021.103113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/16/2021] [Accepted: 09/08/2021] [Indexed: 12/13/2022] Open
Abstract
We have shown previously that prebiotic (Bimuno galacto-oligosacharides, B-GOS®) administration to neonatal rats increased hippocampal NMDAR proteins. The present study has investigated the effects of postnatal B-GOS® supplementation on hippocampus-dependent behavior in young, adolescent, and adult rats and applied electrophysiological, metabolomic and metagenomic analyses to explore potential underlying mechanisms. The administration of B-GOS® to suckling, but not post-weaned, rats reduced anxious behavior until adulthood. Neonatal prebiotic intake also reduced the fast decay component of hippocampal NMDAR currents, altered age-specific trajectories of the brain, intestinal, and liver metabolomes, and reduced abundance of fecal Enterococcus and Dorea bacteria. Our data are the first to show that prebiotic administration to rats during a specific postnatal period has long-term effects on behavior and hippocampal physiology. The study also suggests that early-life prebiotic intake may affect host brain function through the reduction of stress-related gut bacteria rather than increasing the proliferation of beneficial microbes.
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Affiliation(s)
- Sonia O. Spitzer
- Department of Psychiatry, University of Oxford, Warneford Lane, Oxford, OX3 7JX, UK
| | - Andrzej Tkacz
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
| | - Helene M. Savignac
- Quadram Institute, Rosalind Franklin Road, Norwich Research Park, Norwich NR4 7UQ, UK
| | - Matthew Cooper
- Department of Physiology, Anatomy and Genomics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
- Oxford Ion Channel Initiative, University of Oxford, Oxford OX1 3PT, UK
| | - Natasa Giallourou
- Department of Metabolism, Digestion and Reproduction, Imperial College, South Kensington Campus, London SW7 2AZ, UK
| | - Edward O. Mann
- Department of Physiology, Anatomy and Genomics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
- Oxford Ion Channel Initiative, University of Oxford, Oxford OX1 3PT, UK
| | - David M. Bannerman
- Oxford Ion Channel Initiative, University of Oxford, Oxford OX1 3PT, UK
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Woodstock Road, Oxford OX2 6GG, UK
| | - Jonathan R. Swann
- Department of Metabolism, Digestion and Reproduction, Imperial College, South Kensington Campus, London SW7 2AZ, UK
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Daniel C. Anthony
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Philip S. Poole
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
| | - Philip W.J. Burnet
- Department of Psychiatry, University of Oxford, Warneford Lane, Oxford, OX3 7JX, UK
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17
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Intellectual Disability and Brain Creatine Deficit: Phenotyping of the Genetic Mouse Model for GAMT Deficiency. Genes (Basel) 2021; 12:genes12081201. [PMID: 34440375 PMCID: PMC8391262 DOI: 10.3390/genes12081201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/23/2021] [Accepted: 07/25/2021] [Indexed: 11/17/2022] Open
Abstract
Guanidinoacetate methyltransferase deficiency (GAMT-D) is one of three cerebral creatine (Cr) deficiency syndromes due to pathogenic variants in the GAMT gene (19p13.3). GAMT-D is characterized by the accumulation of guanidinoacetic acid (GAA) and the depletion of Cr, which result in severe global developmental delay (and intellectual disability), movement disorder, and epilepsy. The GAMT knockout (KO) mouse model presents biochemical alterations in bodily fluids, the brain, and muscles, including increased GAA and decreased Cr and creatinine (Crn) levels, which are similar to those observed in humans. At the behavioral level, only limited and mild alterations have been reported, with a large part of analyzed behaviors being unaffected in GAMT KO as compared with wild-type mice. At the cerebral level, decreased Cr and Crn and increased GAA and other guanidine compound levels have been observed. Nevertheless, the effects of Cr deficiency and GAA accumulation on many neurochemical, morphological, and molecular processes have not yet been explored. In this review, we summarize data regarding behavioral and cerebral GAMT KO phenotypes, and focus on uncharted behavioral alterations that are comparable with the clinical symptoms reported in GAMT-D patients, including intellectual disability, poor speech, and autistic-like behaviors, as well as unexplored Cr-induced cerebral alterations.
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18
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Ghirardini E, Calugi F, Sagona G, Di Vetta F, Palma M, Battini R, Cioni G, Pizzorusso T, Baroncelli L. The Role of Preclinical Models in Creatine Transporter Deficiency: Neurobiological Mechanisms, Biomarkers and Therapeutic Development. Genes (Basel) 2021; 12:genes12081123. [PMID: 34440297 PMCID: PMC8392480 DOI: 10.3390/genes12081123] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/22/2021] [Accepted: 07/23/2021] [Indexed: 12/12/2022] Open
Abstract
Creatine (Cr) Transporter Deficiency (CTD) is an X-linked metabolic disorder, mostly caused by missense mutations in the SLC6A8 gene and presenting with intellectual disability, autistic behavior, and epilepsy. There is no effective treatment for CTD and patients need lifelong assistance. Thus, the research of novel intervention strategies is a major scientific challenge. Animal models are an excellent tool to dissect the disease pathogenetic mechanisms and drive the preclinical development of therapeutics. This review illustrates the current knowledge about Cr metabolism and CTD clinical aspects, with a focus on mainstay diagnostic and therapeutic options. Then, we discuss the rodent models of CTD characterized in the last decade, comparing the phenotypes expressed within clinically relevant domains and the timeline of symptom development. This analysis highlights that animals with the ubiquitous deletion/mutation of SLC6A8 genes well recapitulate the early onset and the complex pathological phenotype of the human condition. Thus, they should represent the preferred model for preclinical efficacy studies. On the other hand, brain- and cell-specific conditional mutants are ideal for understanding the basis of CTD at a cellular and molecular level. Finally, we explain how CTD models might provide novel insight about the pathogenesis of other disorders, including cancer.
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MESH Headings
- Animals
- Biomarkers/metabolism
- Brain Diseases, Metabolic, Inborn/metabolism
- Brain Diseases, Metabolic, Inborn/pathology
- Brain Diseases, Metabolic, Inborn/therapy
- Central Nervous System/pathology
- Creatine/deficiency
- Creatine/metabolism
- Disease Models, Animal
- Humans
- Mental Retardation, X-Linked/metabolism
- Mental Retardation, X-Linked/pathology
- Mental Retardation, X-Linked/therapy
- Mice
- Plasma Membrane Neurotransmitter Transport Proteins/deficiency
- Plasma Membrane Neurotransmitter Transport Proteins/metabolism
- Rats
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Affiliation(s)
- Elsa Ghirardini
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, I-56128 Pisa, Italy; (E.G.); (G.S.); (R.B.); (G.C.)
- Institute of Neuroscience, National Research Council (CNR), I-56124 Pisa, Italy; (F.C.); (F.D.V.); (M.P.); (T.P.)
| | - Francesco Calugi
- Institute of Neuroscience, National Research Council (CNR), I-56124 Pisa, Italy; (F.C.); (F.D.V.); (M.P.); (T.P.)
- Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, I-50135 Florence, Italy
| | - Giulia Sagona
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, I-56128 Pisa, Italy; (E.G.); (G.S.); (R.B.); (G.C.)
- Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, I-50135 Florence, Italy
| | - Federica Di Vetta
- Institute of Neuroscience, National Research Council (CNR), I-56124 Pisa, Italy; (F.C.); (F.D.V.); (M.P.); (T.P.)
- Department of Biology, University of Pisa, I-56126 Pisa, Italy
| | - Martina Palma
- Institute of Neuroscience, National Research Council (CNR), I-56124 Pisa, Italy; (F.C.); (F.D.V.); (M.P.); (T.P.)
- Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, I-50135 Florence, Italy
| | - Roberta Battini
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, I-56128 Pisa, Italy; (E.G.); (G.S.); (R.B.); (G.C.)
- Department of Clinical and Experimental Medicine, University of Pisa, I-56126 Pisa, Italy
| | - Giovanni Cioni
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, I-56128 Pisa, Italy; (E.G.); (G.S.); (R.B.); (G.C.)
- Department of Clinical and Experimental Medicine, University of Pisa, I-56126 Pisa, Italy
| | - Tommaso Pizzorusso
- Institute of Neuroscience, National Research Council (CNR), I-56124 Pisa, Italy; (F.C.); (F.D.V.); (M.P.); (T.P.)
- Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, I-50135 Florence, Italy
| | - Laura Baroncelli
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, I-56128 Pisa, Italy; (E.G.); (G.S.); (R.B.); (G.C.)
- Institute of Neuroscience, National Research Council (CNR), I-56124 Pisa, Italy; (F.C.); (F.D.V.); (M.P.); (T.P.)
- Correspondence:
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Archibald J, MacMillan EL, Graf C, Kozlowski P, Laule C, Kramer JLK. Metabolite activity in the anterior cingulate cortex during a painful stimulus using functional MRS. Sci Rep 2020; 10:19218. [PMID: 33154474 PMCID: PMC7645766 DOI: 10.1038/s41598-020-76263-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 10/14/2020] [Indexed: 02/07/2023] Open
Abstract
To understand neurochemical brain responses to pain, proton magnetic resonance spectroscopy (1H-MRS) is used in humans in vivo to examine various metabolites. Recent MRS investigations have adopted a functional approach, where acquisitions of MRS are performed over time to track task-related changes. Previous studies suggest glutamate is of primary interest, as it may play a role during cortical processing of noxious stimuli. The objective of this study was to examine the metabolic effect (i.e., glutamate) in the anterior cingulate cortex during noxious stimulation using fMRS. The analysis addressed changes in glutamate and glutamate + glutamine (Glx) associated with the onset of pain, and the degree by which fluctuations in metabolites corresponded with continuous pain outcomes. Results suggest healthy participants undergoing tonic noxious stimulation demonstrated increased concentrations of glutamate and Glx at the onset of pain. Subsequent reports of pain were not accompanied by corresponding changes in glutamate of Glx concentrations. An exploratory analysis on sex revealed large effect size changes in glutamate at pain onset in female participants, compared with medium-sized effects in male participants. We propose a role for glutamate in the ACC related to the detection of a noxious stimulus.
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Affiliation(s)
- J Archibald
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, Canada.
- Department of Experimental Medicine, University of British Columbia, Vancouver, Canada.
| | - E L MacMillan
- Department of Radiology, University of British Columbia, Vancouver, Canada
- ImageTech Lab, Simon Fraser University, Surrey, Canada
- Philips Healthcare Canada, Markham, Canada
| | - C Graf
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
| | - P Kozlowski
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, Canada
- Hughill Center, Vancouver, Canada
- Department of Radiology, University of British Columbia, Vancouver, Canada
- UBC MRI Research Centre, University of British Columbia, Vancouver, Canada
| | - C Laule
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, Canada
- Hughill Center, Vancouver, Canada
- Department of Radiology, University of British Columbia, Vancouver, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
- UBC MRI Research Centre, University of British Columbia, Vancouver, Canada
- Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - J L K Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, Canada
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
- Djavad Mowafaghian Center for Brain Health (DMCH), Vancouver, Canada
- Hughill Center, Vancouver, Canada
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20
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Farr CV, El-Kasaby A, Freissmuth M, Sucic S. The Creatine Transporter Unfolded: A Knotty Premise in the Cerebral Creatine Deficiency Syndrome. Front Synaptic Neurosci 2020; 12:588954. [PMID: 33192443 PMCID: PMC7644880 DOI: 10.3389/fnsyn.2020.588954] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/18/2020] [Indexed: 12/16/2022] Open
Abstract
Creatine provides cells with high-energy phosphates for the rapid reconstitution of hydrolyzed adenosine triphosphate. The eponymous creatine transporter (CRT1/SLC6A8) belongs to a family of solute carrier 6 (SLC6) proteins. The key role of CRT1 is to translocate creatine across tissue barriers and into target cells, such as neurons and myocytes. Individuals harboring mutations in the coding sequence of the human CRT1 gene develop creatine transporter deficiency (CTD), one of the pivotal underlying causes of cerebral creatine deficiency syndrome. CTD encompasses an array of clinical manifestations, including severe intellectual disability, epilepsy, autism, development delay, and motor dysfunction. CTD is characterized by the absence of cerebral creatine, which implies an indispensable role for CRT1 in supplying the brain cells with creatine. CTD-associated variants dramatically reduce or abolish creatine transport activity by CRT1. Many of these are point mutations that are known to trigger folding defects, leading to the retention of encoded CRT1 proteins in the endoplasmic reticulum and precluding their delivery to the cell surface. Misfolding of several related SLC6 transporters also gives rise to detrimental pathologic conditions in people; e.g., mutations in the dopamine transporter induce infantile parkinsonism/dystonia, while mutations in the GABA transporter 1 cause treatment-resistant epilepsy. In some cases, folding defects are amenable to rescue by small molecules, known as pharmacological and chemical chaperones, which restore the cell surface expression and transport activity of the previously non-functional proteins. Insights from the recent molecular, animal and human case studies of CTD add toward our understanding of this complex disorder and reveal the wide-ranging effects elicited upon CRT1 dysfunction. This grants novel therapeutic prospects for the treatment of patients afflicted with CTD, e.g., modifying the creatine molecule to facilitate CRT1-independent entry into brain cells, or correcting folding-deficient and loss-of-function CTD variants using pharmacochaperones and/or allosteric modulators. The latter justifies a search for additional compounds with a capacity to correct mutation-specific defects.
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Affiliation(s)
| | | | | | - Sonja Sucic
- Institute of Pharmacology, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
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21
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Sinha A, Ahmed S, George C, Tsagaris M, Naufer A, von Both I, Tkachyova I, van Eede M, Henkelman M, Schulze A. Magnetic resonance imaging reveals specific anatomical changes in the brain of Agat- and Gamt-mice attributed to creatine depletion and guanidinoacetate alteration. J Inherit Metab Dis 2020; 43:827-842. [PMID: 31951021 DOI: 10.1002/jimd.12215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/30/2019] [Accepted: 01/09/2020] [Indexed: 11/07/2022]
Abstract
Arginine:glycine amidinotransferase- and guanidinoacetate methyltransferase deficiency are severe neurodevelopmental disorders. It is not known whether mouse models of disease express a neuroanatomical phenotype. High-resolution magnetic resonance imaging (MRI) with advanced image analysis was performed in perfused, fixed mouse brains encapsulated with the skull from male, 10-12 week old Agat -exc and B6J.Cg-Gamt tm1Isb mice (n = 48; n = 8 per genotype, strain). T2-weighted MRI scans were nonlinearly aligned to a 3D atlas of the mouse brain with 62 structures identified. Local differences in brain shape related to genotype were assessed by analysis of deformation fields. Creatine (Cr) and guanidinoacetate (GAA) were measured with high-performance liquid chromatography (HPLC) in brain homogenates (n = 24; n = 4 per genotype, strain) after whole-body perfusion. Cr was decreased in the brain of Agat- and Gamt mutant mice. GAA was decreased in Agat-/- and increased in Gamt-/- . Body weight and brain volume were lower in Agat-/- than in Gamt-/- . The analysis of entire brain structures revealed corpus callosum, internal capsule, fimbria and hypothalamus being different between the genotypes in both strains. Eighteen and fourteen significant peaks (local areas of difference in relative size) were found in Agat- and Gamt mutants, respectively. Comparing Agat-/- with Gamt-/- , we found changes in three brain regions, lateral septum, amygdala, and medulla. Intra-strain differences in four brain structures can be associated with Cr deficiency, while the inter-strain differences in three brain structures of the mutant mice may relate to GAA. Correlating these neuroanatomical findings with gene expression data implies the role of Cr metabolism in the developing brain and the importance of early intervention in patients with Cr deficiency syndromes.
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Affiliation(s)
- Ankit Sinha
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Sohail Ahmed
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Chris George
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Melina Tsagaris
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Amriya Naufer
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ingo von Both
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ilona Tkachyova
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Matthijs van Eede
- Mouse Imaging Centre, Toronto Center of Phenogenomics, Toronto, Ontario, Canada
| | - Mark Henkelman
- Mouse Imaging Centre, Toronto Center of Phenogenomics, Toronto, Ontario, Canada
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Andreas Schulze
- Genetics and Genome Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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22
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Rivolta I, Binda A, Masi A, DiFrancesco JC. Cardiac and neuronal HCN channelopathies. Pflugers Arch 2020; 472:931-951. [PMID: 32424620 DOI: 10.1007/s00424-020-02384-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/21/2020] [Accepted: 04/24/2020] [Indexed: 12/31/2022]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed as four different isoforms (HCN1-4) in the heart and in the central and peripheral nervous systems. In the voltage range of activation, HCN channels carry an inward current mediated by Na+ and K+, termed If in the heart and Ih in neurons. Altered function of HCN channels, mainly HCN4, is associated with sinus node dysfunction and other arrhythmias such as atrial fibrillation, ventricular tachycardia, and atrioventricular block. In recent years, several data have also shown that dysfunctional HCN channels, in particular HCN1, but also HCN2 and HCN4, can play a pathogenic role in epilepsy; these include experimental data from animal models, and data collected over genetic mutations of the channels identified and characterized in epileptic patients. In the central nervous system, alteration of the Ih current could predispose to the development of neurodegenerative diseases such as Parkinson's disease; since HCN channels are widely expressed in the peripheral nervous system, their dysfunctional behavior could also be associated with the pathogenesis of neuropathic pain. Given the fundamental role played by the HCN channels in the regulation of the discharge activity of cardiac and neuronal cells, the modulation of their function for therapeutic purposes is under study since it could be useful in various pathological conditions. Here we review the present knowledge of the HCN-related channelopathies in cardiac and neurological diseases, including clinical, genetic, therapeutic, and physiopathological aspects.
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Affiliation(s)
- Ilaria Rivolta
- School of Medicine and Surgery, Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy
| | - Anna Binda
- School of Medicine and Surgery, Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy
| | - Alessio Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Jacopo C DiFrancesco
- School of Medicine and Surgery, Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy. .,Department of Neurology, ASST San Gerardo Hospital, University of Milano-Bicocca, Via Pergolesi, 33, 20900, Monza, MB, Italy.
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23
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Robinson JL, McBreairty LE, Ryan RA, Randunu R, Walsh CJ, Martin GM, Brunton JA, Bertolo RF. Effects of supplemental creatine and guanidinoacetic acid on spatial memory and the brain of weaned Yucatan miniature pigs. PLoS One 2020; 15:e0226806. [PMID: 31905208 PMCID: PMC6944358 DOI: 10.1371/journal.pone.0226806] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 12/05/2019] [Indexed: 11/18/2022] Open
Abstract
The emergence of creatine as a potential cognitive enhancement supplement for humans prompted an investigation as to whether supplemental creatine could enhance spatial memory in young swine. We assessed memory performance and brain concentrations of creatine and its precursor guanidinoacetic acid (GAA) in 14-16-week-old male Yucatan miniature pigs supplemented for 2 weeks with either 200 mg/kg∙d creatine (+Cr; n = 7) or equimolar GAA (157 mg/kg∙d) (+GAA; n = 8) compared to controls (n = 14). Spatial memory tests had pigs explore distinct sets of objects for 5 min. Objects were spatially controlled, and we assessed exploration times of previously viewed objects relative to novel objects in familiar or novel locations. There was no effect of either supplementation on memory performance, but pigs successfully identified novel objects after 10 (p < 0.01) and 20 min (p < 0.01) retention intervals. Moreover, pigs recognized spatial transfers after 65 min (p < 0.05). Regression analyses identified associations between the ability to identify novel objects in memory tests and concentrations of creatine and GAA in cerebellum, and GAA in prefrontal cortex (p < 0.05). The concentration of creatine in brain regions was not influenced by creatine supplementation, but GAA supplementation increased GAA concentration in cerebellum (p < 0.05), and the prefrontal cortex of +GAA pigs had more creatine/g and less GAA/g compared to +Cr pigs (p < 0.05). Creatine kinase activity and maximal reaction velocity were also higher with GAA supplementation in prefrontal cortex (p < 0.05). In conclusion, there appears to be a relationship between memory performance and guanidino compounds in the cerebellum and prefrontal cortex, but the effects were unrelated to dietary supplementation. The cerebellum is identified as a target site for GAA accretion.
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Affiliation(s)
- Jason L. Robinson
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Laura E. McBreairty
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Rebecca A. Ryan
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Raniru Randunu
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Carolyn J. Walsh
- Department of Psychology, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Gerard M. Martin
- Department of Psychology, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Janet A. Brunton
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | - Robert F. Bertolo
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
- * E-mail:
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Untargeted metabolomic profiling reveals multiple pathway perturbations and new clinical biomarkers in urea cycle disorders. Genet Med 2019; 21:1977-1986. [PMID: 30670878 PMCID: PMC6650380 DOI: 10.1038/s41436-019-0442-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 01/09/2019] [Indexed: 12/30/2022] Open
Abstract
Purpose: Untargeted metabolomic analysis is increasingly being used in the screening and management of individuals with inborn errors of metabolism (IEM). We aimed to test whether untargeted metabolomic analysis in plasma might be useful for monitoring the disease course and management of urea cycle disorders (UCDs). Methods: Untargeted mass spectrometry-based metabolomic analysis was used to generate z-scores for more than 900 metabolites in plasma from 48 individuals with various UCDs. Pathway analysis was used to identify common pathways that were perturbed in each UCD. Results: Our metabolomic analysis in plasma identified multiple potentially neurotoxic metabolites of arginine in arginase deficiency and, thus, may have utility in monitoring the efficacy of treatment in arginase deficiency. In addition, we were also able to detect multiple biochemical perturbations in all UCDs that likely reflect clinical management, including metabolite alterations secondary to dietary and medication management. Conclusions: In addition to utility in screening for IEM, our results suggest that untargeted metabolomic analysis in plasma may be beneficial for monitoring efficacy of clinical management and off-target effects of medications in UCDs and potentially other IEM.
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25
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Hjelmervik H, Hausmann M, Craven AR, Hirnstein M, Hugdahl K, Specht K. Sex- and sex hormone-related variations in energy-metabolic frontal brain asymmetries: A magnetic resonance spectroscopy study. Neuroimage 2018; 172:817-825. [DOI: 10.1016/j.neuroimage.2018.01.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 12/22/2017] [Accepted: 01/17/2018] [Indexed: 12/26/2022] Open
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Tachikawa M, Yashiki A, Akanuma SI, Matsukawa H, Ide S, Minami M, Hosoya KI. Astrocytic γ-aminobutyric acid (GABA) transporters mediate guanidinoacetate transport in rat brain. Neurochem Int 2018; 113:1-7. [DOI: 10.1016/j.neuint.2017.11.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 11/11/2017] [Accepted: 11/22/2017] [Indexed: 10/18/2022]
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Dietary guanidinoacetic acid does not accumulate in the brain of healthy men. Eur J Nutr 2017; 57:3003-3005. [PMID: 29255931 DOI: 10.1007/s00394-017-1600-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/14/2017] [Indexed: 10/18/2022]
Abstract
We conducted a secondary analysis of a previously completed trial to determine the effects of 8-week guanidinoacetic acid (GAA) loading on brain GAA levels in five healthy men. Brain magnetic resonance spectroscopy (1H-MRS) was taken at baseline and post-administration, with spectra additionally analyzed for brain GAA and glutamate concentrations using TARQUIN 4.3.10 software. Brain GAA levels remained essentially unchanged at follow-up (an increase of 7.7% from baseline levels; 95% confidence interval, - 24.1% to 39.5%; P = 0.88) when averaged across 12 white and grey matter voxel locations. No significant changes were found for brain glutamate levels during the study (P = 0.64). Supplemental GAA appears to be safe intervention concerning brain GAA deposition, at least with GAA dosages used.
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28
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Lebedev DS, Ivanov IA, Kryukova EV, Starkov VG, Tsetlin VI, Utkin YN. Arginine derivatives of dicarboxylic acids from the parotid gland secretions of common toad Bufo bufo—New agonists of ionotropic γ-aminobutyric acid receptors. DOKL BIOCHEM BIOPHYS 2017; 474:178-182. [DOI: 10.1134/s1607672917030127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Indexed: 11/22/2022]
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29
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Sun W, Wang Y, Zu Z, Jiang Y, Lu W, Wang H, Wu B, Zhang P, Peng X, Zhou H. First reported Chinese case of guanidinoacetate methyltransferase deficiency in a 4-year-old child. Clin Chim Acta 2017; 470:42-45. [PMID: 28438604 DOI: 10.1016/j.cca.2017.04.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 04/14/2017] [Accepted: 04/15/2017] [Indexed: 11/17/2022]
Abstract
Guanidinoacetate methyltransferase (GAMT) deficiency is a rare inherited disorder characterized by creatine (Cr) depletion and guanidinoacetate (GAA) accumulation in body fluids. We report the first identified Chinese case, diagnosed in a 4-year-old girl with onset of global developmental. Low Cr and high GAA levels were detected in her serum and urine, and low Cr level in her brain. Compound heterozygous variants in GAMT gene were found, including a previously reported variant at c.491dupG which was inherited from her mother and a novel variant at c.564G>T, which was inherited from her father. The Cr and GAA levels returned back to normal after 3 months of treatment. After one year of treatment, the patient stopped taking antiepileptic drugs and her electroencephalogram (EEG) was also back to normal. The girl was followed up for five years and exhibited good results beyond our expectation. The results have shown that protein restriction with high-dose ornithine and creatine supplements have strong therapeutic potential for our patient.
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Affiliation(s)
- Weihua Sun
- Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Yi Wang
- Department of Neurology, Children's Hospital of Fudan University, Research Institute of Brain Science, Shanghai, China.
| | - Zhen Zu
- Department of Radiology, Children's Hospital of Shanghai, China
| | - Yi Jiang
- Division of Biochemical Genetics, Baylor Genetics, Houston, TX, USA
| | - Wei Lu
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Huijun Wang
- Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Bingbing Wu
- Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Ping Zhang
- Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Xiaomin Peng
- Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Hao Zhou
- Department of Neurology, Children's Hospital of Fudan University, Research Institute of Brain Science, Shanghai, China
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30
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Six-Week Oral Guanidinoacetic Acid Administration Improves Muscular Performance in Healthy Volunteers. J Investig Med 2016; 63:942-6. [PMID: 26079223 DOI: 10.1097/jim.0000000000000212] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Guanidinoacetic acid (GAA), a natural precursor of creatine, is a new promising dietary supplement, yet its performance-enhancing effect, if any, has yet to be established. The purpose of this pilot study was to evaluate the effects of supplemental GAA on muscle strength, anaerobic performance, and aerobic performance in healthy men and women. METHOD The study enrolled 48 young participants (age, 22.3 ± 1.5 years; height, 176.4 ± 10.0 cm; weight, 71.9 ± 14.3 kg), who received oral doses of GAA (1.2, 2.4, or 4.8 g/d) for 6 weeks in a randomized, double-blind, placebo-controlled trials. RESULTS Significant differences were observed between treatment groups for handgrip strength among participants receiving 1.2 g of GAA per day and 2.4 g of GAA per day, as compared with placebo (P < 0.05). In addition, muscle endurance expressed as the change from baseline in repetitions performed in the bench press exercise was significantly greater in the 1.2 g/d dose of GAA (P = 0.01) and the 4.8 g/d dose (P = 0.01) compared with placebo. No dose-response differences were found between trials. CONCLUSIONS Results from this preliminary study indicate that supplemental GAA ingested in young individuals can improve exercise performance, even at low doses (1.2 g/d).
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31
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Rackayova V, Cudalbu C, Pouwels PJW, Braissant O. Creatine in the central nervous system: From magnetic resonance spectroscopy to creatine deficiencies. Anal Biochem 2016; 529:144-157. [PMID: 27840053 DOI: 10.1016/j.ab.2016.11.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 11/08/2016] [Accepted: 11/09/2016] [Indexed: 10/20/2022]
Abstract
Creatine (Cr) is an important organic compound acting as intracellular high-energy phosphate shuttle and in energy storage. While located in most cells where it plays its main roles in energy metabolism and cytoprotection, Cr is highly concentrated in muscle and brain tissues, in which Cr also appears to act in osmoregulation and neurotransmission. This review discusses the basis of Cr metabolism, synthesis and transport within brain cells. The importance of Cr in brain function and the consequences of its impaired metabolism in primary and secondary Cr deficiencies are also discussed. Cr and phosphocreatine (PCr) in living systems can be well characterized using in vivo magnetic resonance spectroscopy (MRS). This review describes how 1H MRS allows the measurement of Cr and PCr, and how 31P MRS makes it possible to estimate the creatine kinase (CK) rate constant and so detect dynamic changes in the Cr/PCr/CK system. Absolute quantification by MRS using creatine as internal reference is also debated. The use of in vivo MRS to study brain Cr in a non-invasive way is presented, as well as its use in clinical and preclinical studies, including diagnosis and treatment follow-up in patients.
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Affiliation(s)
- Veronika Rackayova
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Cristina Cudalbu
- Centre d'Imagerie Biomedicale (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Petra J W Pouwels
- Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, The Netherlands
| | - Olivier Braissant
- Service of Biomedicine, Neurometabolic Unit, Lausanne University Hospital, Lausanne, Switzerland.
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Snell HD, Gonzales EB. 5-(N, N-Hexamethylene) amiloride is a GABA-A ρ1 receptor positive allosteric modulator. Channels (Austin) 2016; 10:498-506. [PMID: 27367557 PMCID: PMC5034777 DOI: 10.1080/19336950.2016.1207021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/19/2016] [Accepted: 06/20/2016] [Indexed: 10/21/2022] Open
Abstract
Guanidine compounds act as ion channel modulators. In the case of Cys-loop receptors, the guanidine compound amiloride antagonized the heteromeric GABA-A, glycine, and nicotinic acetylcholine receptors. However, amiloride exhibits characteristics consistent with a positive allosteric modulator for the human GABA-A (hGABA-A) ρ1 receptor. Site-directed mutagenesis revealed that the positive allosteric modulation was influenced by the GABA-A ρ1 second transmembrane domain 15' position, a site implicated in ligand allosteric modulation of Cys-loop receptors. There are a variety of amiloride derivatives that provide opportunities to assess the significance of amiloride functional groups (e.g., the guanidine group, the pyrazine ring, etc.) in the modulation of the GABA-A ρ1 receptor activity. We utilized 3 amiloride derivatives (benzamil, phenamil, and 5-(N, N-Hexamethylene) amiloride) to assess the contribution of these groups toward the potentiation of the GABA-A ρ1 receptor. Benzamil and phenamil failed to potentiate on the wild type GABA-A ρ1 GABA-mediated current while HMA demonstrated efficacy only at the highest concentration studied. The hGABA-A ρ1 (I15'N) mutant receptor activity was potentiated by lower HMA concentrations compared to the wild type receptor. Our findings suggest that an exposed guanidine group on amiloride and amiloride derivatives is critical for modulating the GABA-A ρ1 receptor. The present study provides a conceptual framework for predicting which amiloride derivatives will demonstrate positive allosteric modulation of the GABA-A ρ1 receptor.
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Affiliation(s)
- Heather D. Snell
- Center for Neuroscience Discovery, Institute for Healthy Aging, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Eric B. Gonzales
- Center for Neuroscience Discovery, Institute for Healthy Aging, University of North Texas Health Science Center, Fort Worth, TX, USA
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33
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Marques EP, Wyse ATS. Guanidinoacetate Methyltransferase Deficiency. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2016. [DOI: 10.1177/2326409816669371] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Eduardo P. Marques
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Angela T. S. Wyse
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Schulze A, Tran C, Levandovskiy V, Patel V, Cortez MA. Systemic availability of guanidinoacetate affects GABAA receptor function and seizure threshold in GAMT deficient mice. Amino Acids 2016; 48:2041-7. [PMID: 26898547 DOI: 10.1007/s00726-016-2197-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 02/08/2016] [Indexed: 11/29/2022]
Abstract
Deficiency of guanidinoacetate methyltransferase (GAMT) causes creatine depletion and guanidinoacetate accumulation in brain with the latter deemed to be responsible for the severe seizure disorder seen in affected patients. We studied electrical brain activity and GABAA mediated mechanisms of B6J.Cg-Gamt(tm1Isb) mice. Electrocorticographic (ECoG) monitoring of pharmacological treatments with ornithine (5 % in drinking water for 5-18 days) and/or Picrotoxin (PTX) (a GABAA receptor antagonist) (1.5 mg/kg, I.P.) in Gamt(MUT) and Gamt(WT) groups [n = 3, mean age (SEM) = 6.9 (0.2) weeks]. Mice were fitted with two frontal and two parietal epidural electrodes under ketamine/xylazine anesthesia. Baseline and test recordings were performed for determination of seizure activity over a 2 h period. The ECoG baseline of Gamt(MUT) exhibited an abnormal monotonous cortical rhythm (7-8 Hz) with little variability during awake and sleep states compared to wild type recordings. Ornithine treatment and also PTX administration led to a relative normalization of the Gamt(MUT) ECoG phenotype. Gamt(WT) on PTX exhibited electro-behavioral seizures, whereas the Gamt(MUT) did not have PTX induced seizures at the same PTX dose. Gamt(MUT) treated with both ornithine and PTX did not show electro-behavioral seizures while ornithine elevated the PTX seizure threshold of Gamt(MUT) mice even further. These data demonstrate: (1) that there is expression of electrical seizure activity in this Gamt-deficient transgenic mouse strain, and (2) that the systemic availability of guanidinoacetate affects GABAA receptor function and seizure thresholds. These findings are directly and clinically relevant for patients with a creatine-deficiency syndrome due to genetic defects in GAMT and provide a rational basis for a combined ornithine/picrotoxin therapeutic intervention.
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Affiliation(s)
- A Schulze
- Program of Genetics and Genome Biology, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada. .,Department of Pediatrics, University of Toronto, Toronto, ON, Canada.
| | - C Tran
- Program of Genetics and Genome Biology, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.,Center for Molecular Diseases, Lausanne University Hospital, Lausanne, Switzerland
| | - V Levandovskiy
- Program of Genetics and Genome Biology, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - V Patel
- Program of Genetics and Genome Biology, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - M A Cortez
- Department of Pediatrics, University of Toronto, Toronto, ON, Canada.,Program of Brain and Behavior Neuroscience and Mental Health, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, Toronto, ON, Canada
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Hanna-El-Daher L, Braissant O. Creatine synthesis and exchanges between brain cells: What can be learned from human creatine deficiencies and various experimental models? Amino Acids 2016; 48:1877-95. [PMID: 26861125 DOI: 10.1007/s00726-016-2189-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 01/27/2016] [Indexed: 12/11/2022]
Abstract
While it has long been thought that most of cerebral creatine is of peripheral origin, the last 20 years has provided evidence that the creatine synthetic pathway (AGAT and GAMT enzymes) is expressed in the brain together with the creatine transporter (SLC6A8). It has also been shown that SLC6A8 is expressed by microcapillary endothelial cells at the blood-brain barrier, but is absent from surrounding astrocytes, raising the concept that the blood-brain barrier has a limited permeability for peripheral creatine. The first creatine deficiency syndrome in humans was also discovered 20 years ago (GAMT deficiency), followed later by AGAT and SLC6A8 deficiencies, all three diseases being characterized by creatine deficiency in the CNS and essentially affecting the brain. By reviewing the numerous and latest experimental studies addressing creatine transport and synthesis in the CNS, as well as the clinical and biochemical characteristics of creatine-deficient patients, our aim was to delineate a clearer view of the roles of the blood-brain and blood-cerebrospinal fluid barriers in the transport of creatine and guanidinoacetate between periphery and CNS, and on the intracerebral synthesis and transport of creatine. This review also addresses the question of guanidinoacetate toxicity for brain cells, as probably found under GAMT deficiency.
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MESH Headings
- Amidinotransferases/deficiency
- Amidinotransferases/genetics
- Amidinotransferases/metabolism
- Amino Acid Metabolism, Inborn Errors/genetics
- Amino Acid Metabolism, Inborn Errors/metabolism
- Amino Acid Metabolism, Inborn Errors/pathology
- Animals
- Blood-Brain Barrier/metabolism
- Blood-Brain Barrier/pathology
- Brain Diseases, Metabolic, Inborn/genetics
- Brain Diseases, Metabolic, Inborn/metabolism
- Brain Diseases, Metabolic, Inborn/pathology
- Capillaries/metabolism
- Capillaries/pathology
- Creatine/biosynthesis
- Creatine/deficiency
- Creatine/genetics
- Creatine/metabolism
- Developmental Disabilities/genetics
- Developmental Disabilities/metabolism
- Developmental Disabilities/pathology
- Disease Models, Animal
- Endothelial Cells/metabolism
- Endothelial Cells/pathology
- Guanidinoacetate N-Methyltransferase/deficiency
- Guanidinoacetate N-Methyltransferase/genetics
- Guanidinoacetate N-Methyltransferase/metabolism
- Humans
- Intellectual Disability/genetics
- Intellectual Disability/metabolism
- Intellectual Disability/pathology
- Language Development Disorders/genetics
- Language Development Disorders/metabolism
- Language Development Disorders/pathology
- Mental Retardation, X-Linked/genetics
- Mental Retardation, X-Linked/metabolism
- Mental Retardation, X-Linked/pathology
- Movement Disorders/congenital
- Movement Disorders/genetics
- Movement Disorders/metabolism
- Movement Disorders/pathology
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Plasma Membrane Neurotransmitter Transport Proteins/deficiency
- Plasma Membrane Neurotransmitter Transport Proteins/genetics
- Plasma Membrane Neurotransmitter Transport Proteins/metabolism
- Speech Disorders/genetics
- Speech Disorders/metabolism
- Speech Disorders/pathology
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Affiliation(s)
- Layane Hanna-El-Daher
- Service of Biomedicine, Neurometabolic Unit, Lausanne University Hospital, 1011, Lausanne, Switzerland
| | - Olivier Braissant
- Service of Biomedicine, Neurometabolic Unit, Lausanne University Hospital, 1011, Lausanne, Switzerland.
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36
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Ostojic SM. Guanidinoacetic acid as a performance-enhancing agent. Amino Acids 2015; 48:1867-75. [PMID: 26445773 DOI: 10.1007/s00726-015-2106-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 09/22/2015] [Indexed: 01/01/2023]
Abstract
Guanidinoacetic acid (GAA; also known as glycocyamine or guanidinoacetate) is the natural precursor of creatine, and under investigation as a novel dietary agent. It was first identified as a natural compound in humans ~80 years ago. In the 1950s, GAA's use as a therapeutic agent was explored, showing that supplemental GAA improved patient-reported outcomes and work capacity in clinical populations. Recently, a few studies have examined the safety and efficacy of GAA and suggest potential ergogenic benefits for physically active men and women. The purpose of this review is to examine possible applications of GAA supplementation for exercise performance enhancement, safety, and legislation issues.
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Affiliation(s)
- Sergej M Ostojic
- Biomedical Sciences Department, Faculty of Sport and Physical Education, University of Novi Sad, Lovcenska 16, Novi Sad, 21000, Serbia. .,University of Belgrade School of Medicine, Belgrade, Serbia.
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37
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Advanced physiological roles of guanidinoacetic acid. Eur J Nutr 2015; 54:1211-5. [DOI: 10.1007/s00394-015-1050-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/16/2015] [Indexed: 02/04/2023]
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38
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Rae C, Nasrallah FA, Balcar VJ, Rowlands BD, Johnston GAR, Hanrahan JR. Metabolomic Approaches to Defining the Role(s) of GABAρ Receptors in the Brain. J Neuroimmune Pharmacol 2015; 10:445-56. [PMID: 25577264 DOI: 10.1007/s11481-014-9579-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Accepted: 12/26/2014] [Indexed: 10/24/2022]
Abstract
The inhibitory neurotransmitter γ-aminobutyric acid (GABA) acts through various types of receptors in the central nervous system. GABAρ receptors, defined by their characteristic pharmacology and presence of ρ subunits in the channel structure, are poorly understood and their role in the cortex is ill-defined. Here, we used a targeted pharmacological, NMR-based functional metabolomic approach in Guinea pig brain cortical tissue slices to identify a distinct role for these receptors. We compared metabolic fingerprints generated by a range of ligands active at GABAρ and included these in a principal components analysis with a library of other metabolic fingerprints obtained using ligands active at GABAA and GABAB, with inhibitors of GABA uptake and with compounds acting to inhibit enzymes active in the GABAergic system. This enabled us to generate a metabolic "footprint" of the GABAergic system which revealed classes of metabolic activity associated with GABAρ which are distinct from other GABA receptors. Antagonised GABAρ produce large metabolic effects at extrasynaptic sites suggesting they may be involved in tonic inhibition.
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Affiliation(s)
- Caroline Rae
- Neuroscience Research Australia, Barker St, Randwick, NSW, 2031, Australia,
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39
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Furuse M. Screening of central functions of amino acids and their metabolites for sedative and hypnotic effects using chick models. Eur J Pharmacol 2015; 762:382-93. [DOI: 10.1016/j.ejphar.2015.06.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 06/16/2015] [Accepted: 06/17/2015] [Indexed: 11/29/2022]
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40
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Mercimek-Mahmutoglu S, Pop A, Kanhai W, Fernandez Ojeda M, Holwerda U, Smith D, Loeber JG, Schielen PCJI, Salomons GS. A pilot study to estimate incidence of guanidinoacetate methyltransferase deficiency in newborns by direct sequencing of the GAMT gene. Gene 2015; 575:127-31. [PMID: 26319512 DOI: 10.1016/j.gene.2015.08.045] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 08/21/2015] [Accepted: 08/23/2015] [Indexed: 11/17/2022]
Abstract
BACKGROUND GAMT deficiency is an autosomal recessive disorder of creatine biosynthesis causing developmental delays or intellectual disability in untreated patients as a result of irreversible brain damage occurring prior to diagnosis. Normal neurodevelopmental outcome has been reported in patients treated from neonatal period highlighting the importance of early treatment. METHODS Five hundred anonymized newborns from the National Newborn Screening Program of The Netherlands were included into this pilot study. Direct sequencing of the coding region of the GAMT gene was applied following DNA extraction. The disease causing nature of novel missense variants in the GAMT gene was studied by overexpression studies. GAA and creatine was measured in blood dot spots. RESULTS We detected two carriers, one with a known common (c.327G>A) and one with a novel mutation (c.297_309dup (p.Arg105Glyfs*) in the GAMT gene. The estimated incidence of GAMT deficiency was 1:250,000. We also detected five novel missense variants. Overexpression of these variants in GAMT deficient fibroblasts did restore GAMT activity and thus all were considered rare, but not disease causing variants including the c.131G>T (p.Arg44Leu) variant. Interestingly, this variant was predicted to be pathogenic by in silico analysis. The variants were included in the Leiden Open Variation Database (LOVD) database (www.LOVD.nl/GAMT). The average GAA level was 1.14μmol/L±0.45 standard deviations. The average creatine level was 408μmol/L±106. The average GAA/creatine ratio was 2.94±0.136. CONCLUSION The estimated incidence of GAMT deficiency is 1:250,000 newborns based on our pilot study. The newborn screening for GAMT deficiency should be implemented to identify patients at the asymptomatic stage to achieve normal neurodevelopmental outcome for this treatable neurometabolic disease. Biochemical investigations including GAA, creatine and GAMT enzyme activity measurements are essential to confirm the diagnosis of GAMT deficiency. According to availability, all missense variants can be assessed functionally, as in silico prediction analysis of missense variants is not sufficient to confirm the pathogenicity of missense variants.
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Affiliation(s)
- S Mercimek-Mahmutoglu
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, Canada; Genetics and Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada.
| | - A Pop
- Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, Neurosciences Campus, Amsterdam, The Netherlands
| | - W Kanhai
- Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, Neurosciences Campus, Amsterdam, The Netherlands
| | - M Fernandez Ojeda
- Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, Neurosciences Campus, Amsterdam, The Netherlands
| | - U Holwerda
- Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, Neurosciences Campus, Amsterdam, The Netherlands
| | - D Smith
- Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, Neurosciences Campus, Amsterdam, The Netherlands
| | - J G Loeber
- National Institute for Public Health and the Environment, Centre for Infectious Diseases Research, and Screening, Bilthoven, The Netherlands
| | - P C J I Schielen
- National Institute for Public Health and the Environment, Centre for Infectious Diseases Research, and Screening, Bilthoven, The Netherlands
| | - G S Salomons
- Metabolic Unit, Department of Clinical Chemistry, VU Medical Center, Neurosciences Campus, Amsterdam, The Netherlands.
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41
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Rae CD, Bröer S. Creatine as a booster for human brain function. How might it work? Neurochem Int 2015; 89:249-59. [PMID: 26297632 DOI: 10.1016/j.neuint.2015.08.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 08/04/2015] [Accepted: 08/15/2015] [Indexed: 01/19/2023]
Abstract
Creatine, a naturally occurring nitrogenous organic acid found in animal tissues, has been found to play key roles in the brain including buffering energy supply, improving mitochondrial efficiency, directly acting as an anti-oxidant and acting as a neuroprotectant. Much of the evidence for these roles has been established in vitro or in pre-clinical studies. Here, we examine the roles of creatine and explore the current status of translation of this research into use in humans and the clinic. Some further possibilities for use of creatine in humans are also discussed.
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Affiliation(s)
- Caroline D Rae
- Neuroscience Research Australia, Barker St Randwick, NSW 2031, Australia; School of Medical Sciences, UNSW, High Street, Randwick, NSW 2052, Australia.
| | - Stefan Bröer
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
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42
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Hanna-El-Daher L, Béard E, Henry H, Tenenbaum L, Braissant O. Mild guanidinoacetate increase under partial guanidinoacetate methyltransferase deficiency strongly affects brain cell development. Neurobiol Dis 2015; 79:14-27. [DOI: 10.1016/j.nbd.2015.03.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 03/27/2015] [Accepted: 03/31/2015] [Indexed: 11/15/2022] Open
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43
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Kaji MD, Kwaka A, Callanan MK, Nusrat H, Desaulniers JP, Forrester SG. A molecular characterization of the agonist binding site of a nematode cys-loop GABA receptor. Br J Pharmacol 2015; 172:3737-47. [PMID: 25850584 DOI: 10.1111/bph.13158] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 03/30/2015] [Accepted: 03/31/2015] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Cys-loop GABA receptors represent important targets for human chemotherapeutics and insecticides and are potential targets for novel anthelmintics (nematicides). However, compared with insect and mammalian receptors, little is known regarding the pharmacological characteristics of nematode Cys-loop GABA receptors. Here we have investigated the agonist binding site of the Cys-loop GABA receptor UNC-49 (Hco-UNC-49) from the parasitic nematode Haemonchus contortus. EXPERIMENTAL APPROACH We used two-electrode voltage-clamp electrophysiology to measure channel activation by classical GABA receptor agonists on Hco-UNC-49 expressed in Xenopus laevis oocytes, along with site-directed mutagenesis and in silico homology modelling. KEY RESULTS The sulphonated molecules P4S and taurine had no effect on Hco-UNC-49. Other classical Cys-loop GABAA receptor agonists tested on the Hco-UNC-49B/C heteromeric channel had a rank order efficacy of GABA > trans-4-aminocrotonic acid > isoguvacine > imidazole-4-acetic acid (IMA) > (R)-(-)-4-amino-3-hydroxybutyric acid [R(-)-GABOB] > (S)-(+)-4-amino-3-hydroxybutyric acid [S(+)-GABOB] > guanidinoacetic acid > isonipecotic acid > 5-aminovaleric acid (DAVA) (partial agonist) > β-alanine (partial agonist). In silico ligand docking revealed some variation in binding between agonists. Mutagenesis of a key serine residue in binding loop C to threonine had minimal effects on GABA and IMA but significantly increased the maximal response to DAVA and decreased twofold the EC50 for R(-)- and S(+)-GABOB. CONCLUSIONS AND IMPLICATIONS The pharmacological profile of Hco-UNC-49 differed from that of vertebrate Cys-loop GABA receptors and insect resistance to dieldrin receptors, suggesting differences in the agonist binding pocket. These findings could be exploited to develop new drugs that specifically target GABA receptors of parasitic nematodes.
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Affiliation(s)
- Mark D Kaji
- Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Ariel Kwaka
- Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Micah K Callanan
- Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Humza Nusrat
- Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Jean-Paul Desaulniers
- Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
| | - Sean G Forrester
- Faculty of Science, University of Ontario Institute of Technology, Oshawa, ON, Canada
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44
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Snell HD, Gonzales EB. Amiloride and GMQ Allosteric Modulation of the GABA-A ρ1 Receptor: Influences of the Intersubunit Site. J Pharmacol Exp Ther 2015; 353:551-9. [PMID: 25829529 DOI: 10.1124/jpet.115.222802] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/31/2015] [Indexed: 11/22/2022] Open
Abstract
Amiloride, a diuretic used in the treatment of hypertension and congestive heart failure, and 2-guanidine-4-methylquinazoline (GMQ) are guanidine compounds that modulate acid-sensing ion channels. Both compounds have demonstrated affinity for a variety of membrane proteins, including members of the Cys-loop family of ligand-gated ion channels, such as the heteromeric GABA-A αβγ receptors. The actions of these guanidine compounds on the homomeric GABA-A ρ1 receptor remains unclear, especially in light of how many GABA-A αβγ receptor modulators have different effects in the GABA-A ρ1 receptors. We sought to characterize the influence of amiloride and GMQ on the human GABA-A ρ1 receptors using whole-cell patch-clamp electrophysiology. The diuretic amiloride potentiated the human GABA-A ρ1 GABA-mediated current, whereas GMQ antagonized the receptor. Furthermore, a GABA-A second transmembrane domain site, the intersubunit site, responsible for allosteric modulation in the heteromeric GABA-A receptors mediated amiloride's positive allosteric actions. In contrast, the mutation did not remove GMQ antagonism but only changed the guanidine compound's potency within the human GABA-A ρ1 receptor. Through modeling and introduction of point mutations, we propose that the GABA-A ρ1 intersubunit site plays a role in mediating the allosteric effects of amiloride and GMQ.
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Affiliation(s)
- Heather D Snell
- Department of Pharmacology and Neuroscience (H.D.S., E.B.G.), Institute for Aging and Alzheimer's Disease Research (E.B.G.), and Cardiovascular Research Institute (E.B.G.), University of North Texas Health Science Center, Fort Worth, Texas
| | - Eric B Gonzales
- Department of Pharmacology and Neuroscience (H.D.S., E.B.G.), Institute for Aging and Alzheimer's Disease Research (E.B.G.), and Cardiovascular Research Institute (E.B.G.), University of North Texas Health Science Center, Fort Worth, Texas
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45
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Ostojic SM, Stojanovic M. Guanidinoacetic acid loading affects plasma γ-aminobutyric acid in healthy men. Eur J Nutr 2015; 54:855-8. [DOI: 10.1007/s00394-015-0858-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 02/05/2015] [Indexed: 11/30/2022]
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Barón-Sola Á, Sanz-Alférez S, Del Campo FF. First evidence of accumulation in cyanobacteria of guanidinoacetate, a precursor of the toxin cylindrospermopsin. CHEMOSPHERE 2015; 119:1099-1104. [PMID: 25460748 DOI: 10.1016/j.chemosphere.2014.08.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/17/2014] [Accepted: 08/19/2014] [Indexed: 06/04/2023]
Abstract
Guanidinoacetate (GAA) is one of the most extensively studied toxic guanidine compounds. Changes in GAA can affect the nervous system and induce hyperhomocysteinemia, representing a risk factor for cardiovascular diseases. In cyanobacteria, GAA is thought to be an intermediate in the synthesis of the toxin cylindrospermopsin (CYN), one of the most common known cyanotoxins that affects multiple organs and functions in animals and plants. In spite of the evidence supporting GAA toxicity and its role in CYN synthesis, no data have been reported on the accumulation of GAA in any cyanobacterium. We have analyzed and compared the content of GAA in cultures of diverse cyanobacteria types, both cylindrospermopsin producing (CYN(+)) and not producing (CYN(-)). The results obtained show that GAA accumulates in the majority of the strains tested, although the highest content was found in one of the CYN(+) strain, Aphanizomenon ovalisporum UAM-MAO. In this strain, both GAA and CYN can be located within and out the cells. In conclusion, GAA appears to be a general cyanobacterial metabolite that due to its proven toxic should be considered when studying and managing cyanobacteria toxicity.
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Affiliation(s)
- Ángel Barón-Sola
- Departamento de Biología, C/Darwin 2, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Soledad Sanz-Alférez
- Departamento de Biología, C/Darwin 2, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Francisca F Del Campo
- Departamento de Biología, C/Darwin 2, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
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47
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Dhaked DK, Bharatam PV. Conformational and zwitterionic preferences of N-amidinoglycine: the effect of microsolvation and metal ion addition. RSC Adv 2014. [DOI: 10.1039/c4ra06079b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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48
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Petersen JG, Sørensen T, Damgaard M, Nielsen B, Jensen AA, Balle T, Bergmann R, Frølund B. Synthesis and pharmacological evaluation of 6-aminonicotinic acid analogues as novel GABAA receptor agonists. Eur J Med Chem 2014; 84:404-16. [DOI: 10.1016/j.ejmech.2014.07.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/10/2014] [Accepted: 07/11/2014] [Indexed: 12/11/2022]
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49
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Rae CD. A Guide to the Metabolic Pathways and Function of Metabolites Observed in Human Brain 1H Magnetic Resonance Spectra. Neurochem Res 2013; 39:1-36. [PMID: 24258018 DOI: 10.1007/s11064-013-1199-5] [Citation(s) in RCA: 327] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 11/08/2013] [Accepted: 11/11/2013] [Indexed: 12/20/2022]
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50
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2-Guanidine-4-methylquinazoline acts as a novel competitive antagonist of A type γ-aminobutyric acid receptors. Neuropharmacology 2013; 75:126-37. [PMID: 23916476 DOI: 10.1016/j.neuropharm.2013.07.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 06/13/2013] [Accepted: 07/16/2013] [Indexed: 11/18/2022]
Abstract
The pentameric A type γ-aminobutyric acid receptors (GABAARs) are the major inhibitory neurotransmitter receptors in the nervous system and have long been considered as important pharmaceutical targets for the treatment of multiple neurological or psychological disorders. Here, we show that 2-guanidine-4-methylquinazoline (GMQ), a recently identified acid-sensing ion channel (ASIC) modulator, strongly and preferentially inhibits GABAAR among the major neurotransmitter-gated ion channels in cultured rat hippocampal neurons. GMQ inhibited GABA (1 μM)-induced currents in a competitive manner, with an IC50 (0.39±0.05 μM) comparable to that of bicuculline. Schild analysis revealed a slope of 1.04±0.06 for GMQ on α1β2 GABAARs expressed in HEK293T cells. Single-channel analysis showed that GMQ decreased open probability of GABAARs without affecting conductance. Moreover, GMQ inhibited GABAergic neurotransmission in hippocampal neurons, while having no significant effect on the basal field excitatory postsynaptic potentials (fEPSPs) and the intrinsic excitability of neurons. Using site-directed mutagenesis, we further demonstrated that mutations at Glu155 of β2 subunit and Phe64 of α1 subunit, both located inside the GABA binding pocket, profoundly decreased the sensitivity of the receptor to both GABA and GMQ. Interestingly, these mutations did not significantly affect the inhibition by amiloride, a diuretic structurally similar to GMQ and a known GABAAR inhibitor. We conclude that GMQ represents a novel chemical structure that acts, possibly, by competing with GABA binding to GABAARs. It is anticipated that GMQ and its analogs will facilitate the development of new chemical probes for GABAARs.
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