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Lidia D Martínez, Miriam Bezard, Mabel Brunotto, Raquel Dodelson de Kremer
Creatine (Cr) plays an important role in storage and transmission of phosphate-bound energy. Cerebral creatine deficiency syndromes comprise three inherited defects in Cr biosynthesis and transport. The aim of this study was to investigate whether Cr and Guanidinoacetate (GAA) can be detected in saliva of healthy subjects and to establish the relationship between salivary and plasma levels of these molecules. An adapted gas chromatography (GC) method is described for the quantification of Cr and GAA biomarkers in saliva...
April 2016: Acta Odontológica Latinoamericana: AOL
Valdemar Stajer, Tatjana Trivic, Patrik Drid, Milan Vranes, Sergej M Ostojic
We evaluated the effects of exercise on circulating concentrations of guanidinoacetic acid (GAA) and creatine in 23 healthy volunteers subjected to running to exhaustion and free-weight bench-press to volitional failure. Blood was taken before and following each exercise session. Running induced a significant decrease in serum GAA by 20.1% (P < 0.001), while free-weight exercise reduced GAA by 11.7% (P < 0.001), suggesting the possible use of serum GAA as a novel biomarker of exhaustion.
July 19, 2016: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Iliyana Pacheva, Ivan Ivanov, Marin Penkov, Daliya Kancheva, Albena Jordanova, Mariya Ivanova
A case with GAMT deficiency (homozygous c.64dupG mutation) presented with neurodevelopmental delay, rare seizures, behavioral disturbances, and mild hypotonia, posing diagnostic challenges. Metabolic investigations showed low creatinine in plasma and urine (guanidinoacetate couldn't be investigated) and slightly elevated lactate. MRI was normal. Correct diagnosis was possible only after MR spectroscopy was performed at age 5½ years. A homozygous c.64dupG mutation of the GAMT gene was identified in the proband...
September 2016: Annals of Clinical and Laboratory Science
Murali Ganesan, Dan Feng, Ryan W Barton, Paul G Thomes, Benita L McVicker, Dean J Tuma, Natalia A Osna, Kusum K Kharbanda
BACKGROUND: Alcohol-induced reduction in the hepatocellular S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) ratio impairs the activities of many SAM-dependent methyltransferases. These impairments ultimately lead to the generation of several hallmark features of alcoholic liver injury including steatosis. Guanidinoacetate methyltransferase (GAMT) is an important enzyme that catalyzes the final reaction in the creatine biosynthetic process. The liver is a major site for creatine synthesis which places a substantial methylation burden on this organ as GAMT-mediated reactions consume as much as 40% of all the SAM-derived methyl groups...
September 1, 2016: Alcoholism, Clinical and Experimental Research
Yuanyuan Zhang, Liqiang Gu, Yu Jiang, Kaishun Bi, Xiaohui Chen
Fast and sensitive monitoring of drug-induced liver and kidney injury in early stage is beneficial. An ultrafast liquid chromatography with tandem mass spectrometry assay was developed and validated to simultaneously determine ten endogenous biomarkers in serum and urine, including hippuric acid, phenylacetylglycine, 5-oxoproline, cholic acid, taurine, indoleacetic acid, 3-indoxyl sulfate, guanidinosuccinic acid, guanidinoacetic acid and uric acid. A CAPCELL CORE PC column (2.1 × 150 mm, 2.7 μm) was adopted for analytes separation...
October 2016: Journal of Separation Science
Sergej M Ostojic, Jelena Ostojic, Patrik Drid, Milan Vranes
In this randomized, double-blind, crossover trial, we evaluated whether 4-week supplementation with guanidinoacetic acid (GAA) is superior to creatine in facilitating creatine levels in healthy men (n = 5). GAA (3.0 g/day) resulted in a more powerful rise (up to 16.2%) in tissue creatine levels in vastus medialis muscle, middle-cerebellar peduncle, and paracentral grey matter, as compared with creatine (P < 0.05). These results indicate that GAA as a preferred alternative to creatine for improved bioenergetics in energy-demanding tissues...
September 2016: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Louise Deldicque, Marc Francaux
PURPOSE OF REVIEW: The purpose of this article is to collect the most recent data regarding the safety of well-known or emerging dietary supplements used by athletes. RECENT FINDINGS: From January 2014 to April 2016, about 30 articles have been published in the field. New data show that 90% of sports supplements contain trace of estrogenic endocrine disruptors, with 25% of them having a higher estrogenic activity than acceptable. About 50% of the supplements are contaminated by melamine, a source of nonprotein nitrogen...
November 2016: Current Opinion in Clinical Nutrition and Metabolic Care
Sergej M Ostojic, Jelena Ostojic, Patrik Drid, Milan Vranes, Pavle Jovanov
OBJECTIVE: Guanidinoacetic acid (GAA) is an experimental dietary additive that might act as a creatine source in tissues with high-energy requirements. In this case study, we evaluated brain levels of creatine in white matter, gray matter, cerebellum, and thalamus during 8 wk oral GAA administration in five healthy men and monitored the prevalence and severity of side effects of the intervention. METHODS: Volunteers were supplemented daily with 36 mg/kg body weight (BW) of GAA for the first 4 wk of the intervention; afterward GAA dosage was titrated ≤60 mg/kg BW of GAA daily...
June 8, 2016: Nutrition
Laura Gonzalez-Calero, Marta Martin-Lorenzo, Paula J Martínez, Montserrat Baldan-Martin, Gema Ruiz-Hurtado, Julian Segura, Fernando de la Cuesta, Maria G Barderas, Luis M Ruilope, Fernando Vivanco, Gloria Alvarez-Llamas
Hypertension (HTN) is increasing in prevalence, and albuminuria is a strong indicator of cardiovascular risk and renal damage progression. Despite blood pressure control with chronic treatment, a relevant subgroup of patients develop albuminuria. However, the biological factors responsible for albuminuria development and progression are underexplored. We aimed to identify key metabolic targets and biological pathways involved in the negative progression of cardiovascular and renal damage in hypertensives undergoing chronic treatment...
July 15, 2016: Translational Research: the Journal of Laboratory and Clinical Medicine
O Ardon, M Procter, R Mao, N Longo, Y E Landau, A Shilon-Hadass, L V Gabis, C Hoffmann, M Tzadok, G Heimer, S Sada, B Ben-Zeev, Y Anikster
X-linked cerebral creatine deficiency (MIM 300036) is caused by deficiency of the creatine transporter encoded by the SLC6A8 gene. Here we report three patients with this condition from Israel. These unrelated patients were evaluated for global developmental delays and language apraxia. Borderline microcephaly was noted in one of them. Diagnosis was prompted by brain magnetic resonance imaging and spectroscopy which revealed normal white matter distribution, but absence of the creatine peak in all three patients...
September 2016: Molecular Genetics and Metabolism Reports
Sergej M Ostojic, Patrik Drid, Jelena Ostojic, Jay R Hoffman
No abstract text is available yet for this article.
May 2016: Medicine and Science in Sports and Exercise
Graham B Sinclair, Clara D M van Karnebeek, Manuel Ester, Frances Boyd, Tanya Nelson, Sylvia Stockler-Ipsiroglu, Hilary Vallance
BACKGROUND: Guanidinoacetate methyltransferase (GAMT) deficiency is a rare disorder of creatine biosynthesis presenting with epilepsy and developmental delay in infancy. Excellent developmental outcomes have been reported for infants treated from birth due to a family history. The BC Newborn Screening Program initiated a 3year pilot screening study for GAMT deficiency to evaluate the performance of a novel three-tiered screening approach. METHODS: Over 36months all bloodspots submitted for routine newborn screening were included in the pilot study (de-identified)...
July 2016: Molecular Genetics and Metabolism
Laura E McBreairty
Methionine is an essential amino acid which when not incorporated into protein, can be converted to S-adenosylmethionine, the universal methyl donor in over 200 transmethylation reactions, which include creatine and phosphatidylcholine (PC) synthesis, as well as deoxyribonucleic acid (DNA) methylation. Following transmethylation, homocysteine is formed, which can be converted to cysteine via transsulfuration or remethylated to methionine by receiving a methyl group from folate or betaine. Changes to methyl group availability in utero can lead to permanent changes in epigenetic patterns of DNA methylation, which has been implicated in "fetal programming", a phenomenon associated with poor nutrition during fetal development that results in low birth weight and disease in later life...
June 2016: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Martina Huemer, Daniel R Carvalho, Jaime M Brum, Özlem Ünal, Turgay Coskun, James D Weisfeld-Adams, Nina L Schrager, Sabine Scholl-Bürgi, Andrea Schlune, Markus G Donner, Martin Hersberger, Claudio Gemperle, Brunhilde Riesner, Hanno Ulmer, Johannes Häberle, Daniela Karall
BACKGROUND: Arginase 1 (ARG1) deficiency is a rare urea cycle disorder (UCD). This hypothesis-generating study explored clinical phenotypes, metabolic profiles, molecular genetics, and treatment approaches in a cohort of children and adults with ARG1 deficiency to add to our understanding of the underlying pathophysiology. METHODS: Clinical data were retrieved retrospectively from physicians using a questionnaire survey. Plasma aminoacids, guanidinoacetate (GAA), parameters indicating oxidative stress and nitric oxide (NO) synthesis as well as asymmetric dimethylarginine (ADMA) were measured at a single study site...
May 2016: Journal of Inherited Metabolic Disease
Yasushi Ogasawara, Junpei Kawata, Motoyoshi Noike, Yasuharu Satoh, Kazuo Furihata, Tohru Dairi
We recently identified a novel peptide ligase (PGM1), an ATP-grasp-ligase, that catalyzes amide bond formation between (S)-2-(3,5-dihydroxy-4-methoxyphenyl)-2-guanidinoacetic acid and ribosomally supplied oligopeptides in pheganomycin biosynthesis. This was the first example of an ATP-grasp-ligase utilizing peptides as nucleophiles. To explore the potential of this type of enzyme, we performed a BLAST search and identified many orthologs. The orthologs of Streptomyces mobaraensis, Salinispora tropica, and Micromonospora sp...
June 17, 2016: ACS Chemical Biology
A Schulze, C Tran, V Levandovskiy, V Patel, M A Cortez
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...
August 2016: Amino Acids
Mette Schmedes, Eli Kristin Aadland, Ulrik Kraemer Sundekilde, Hélène Jacques, Charles Lavigne, Ingvild Eide Graff, Øyvin Eng, Asle Holthe, Gunnar Mellgren, Jette Feveile Young, Hanne Christine Bertram, Bjørn Liaset, Morten Rahr Clausen
SCOPE: Proteins constitute an important part of the human diet, but understanding of the effects of different dietary protein sources on human metabolism is sparse. We aimed to elucidate diet-induced metabolic changes through untargeted urinary metabolomics after four weeks of intervention with lean-seafood or nonseafood diets. It is shown that lean-seafood intake reduces urinary excretion of metabolites involved in mitochondrial lipid and energy metabolism possibly facilitating a higher lipid catabolism in healthy subjects...
July 2016: Molecular Nutrition & Food Research
Layane Hanna-El-Daher, Olivier Braissant
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...
August 2016: Amino Acids
Rizwan Ali Zounr, Mumammad Yar Khuhawar, Taj Muhammad Jahangir, Malik Alamgir
An improved GC method in terms of sensitivity and decrease in the analysis time has been developed for the analysis of eight guanidino compounds: guanidine (G), methylguanidine (MG), creatinine (CTN), guanidinoacetic acid (GAA), guanidinobutyric acid (GBA), guanidinopropionic acid (GPA), argenine (Arg), and guanidinosuccinic acid (GSA), using isovaleroylacetone (IVA) and ethyl chloroformate (ECF) as derivatizing reagents. The separation was obtained from column HP-5 (30 m × 0.32 mm i.d.) with film thickness of 0...
2016: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
Sergej M Ostojic, Marko Stojanovic, Patrik Drid, Jay R Hoffman, Damir Sekulic, Natasa Zenic
A variety of dietary interventions has been used in the management of chronic fatigue syndrome (CFS), yet no therapeutic modality has demonstrated conclusive positive results in terms of effectiveness. The main aim of this study was to evaluate the effects of orally administered guanidinoacetic acid (GAA) on multidimensional fatigue inventory (MFI), musculoskeletal soreness, health-related quality of life, exercise performance, screening laboratory studies, and the occurrence of adverse events in women with CFS...
February 2016: Nutrients
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