OBJECTIVES Guanidinoacetic acid (GAA) is a natural precursor of creatine, yet the potential use of GAA as a nutritional additive for restoring creatine availability in humans has been limited by unclear efficacy and safety after exogenous GAA administration. The present study evaluated the effects of orally administered GAA on serum and urinary GAA, creatine and creatinine concentration, and on...

We have used a peptide-based targeting system to improve lysosomal delivery of acid α-glucosidase (GAA), the enzyme deficient in patients with Pompe disease. Human GAA was fused to the glycosylation-independent lysosomal targeting (GILT) tag, which contains a portion of insulin-like growth factor II, to create an active, chimeric enzyme with high affinity for the cation-independent mannose 6-ph...

Guanidinoacetic acid (GAA) is the natural biosynthetic precursor of creatine, in a metabolic reaction that requires only a methyl group transfer. The use of GAA as a food additive for restoring creatine load in human tissues is rather unexplored and data on efficacy and safety are limited. In particular, an increase in serum homocysteine after GAA administration can be regarded as critical and ...

BACKGROUND Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disease caused by GAA repeat expansion in the first intron of the FXN gene, which encodes frataxin, an essential mitochondrial protein. To further characterise the molecular abnormalities associated with FRDA pathogenesis and to hasten drug screening, the development and use of animal and cellular models is consider...

Abstract Guanidino acetic acid, or GAA, is the only direct precursor of creatinine and involved in biological processes cellular energy vertebrates. Creatine will be used muscle target cells to phosphorylated into phosphocreatine utilizing creatine kinase, which functions buffer ATP changes. GAA biosynthesis for growth performance broiler chickens, it also claimed capable conserving arginine. T...

The semi-essential nutrient creatine is an important molecule in the cellular energy metabolism for short term energy storage. Energy from surplus adenosine tri-phosphate (ATP) can quickly be overtaken by creatine and vice versa. Supplemental guanidino acetic acid (GAA) is a natural precursor of creatine and might be used as creatine source. Either no (negative control), 0.20, 0.40, or 0.60 g/k...

SLC16A12 is a recently identified creatine transporter of unknown physiological function. A heterozygous mutation in the human gene causes juvenile cataracts and reduced plasma guanidinoacetate (GAA) levels with an increased fractional urinary excretion GAA. Our study transgenic SLC16A12-deficient rats reveals that critical for tubular reabsorption GAA kidney. data furthermore indicate dominant...

A fraction of the body's creatine and creatine phosphate spontaneously degrades to creatinine, which is excreted by the kidneys. In humans, this amounts to approximately 1-2 g/day and demands a comparable rate of de novo creatine synthesis. This is a two-step process in which l-arginine:glycine amidinotransferase (AGAT) catalyzes the conversion of glycine and arginine to ornithine and guanidino...

BACKGROUND Friedreich's ataxia (FRDA) is the most common hereditary ataxia among caucasians. The molecular defect in FRDA is the trinucleotide GAA expansion in the first intron of the FXN gene, which encodes frataxin. No studies have yet reported frataxin protein and mRNA levels in a large cohort of FRDA patients, carriers and controls. METHODOLOGY/PRINCIPAL FINDINGS We enrolled 24 patients w...

Friedreich ataxia (FRDA) is a neurodegenerative disorder caused by an unstable GAA repeat expansion mutation within intron 1 of the FXN gene. However, the origins of the GAA repeat expansion, its unstable dynamics within different cells and tissues, and its effects on frataxin expression are not yet completely understood. Therefore, we have chosen to generate representative FRDA mouse models by...