1. The effect of guanosine on L-[3H] glutamate uptake was investigated in brain cortical slices within physio-pathological range of glutamate(1-1000 microM). In these conditions, glutamate uptake was significantly enhanced in slices treated with 100 microM guanosine only at 100 and 300 microM glutamate (44 and 52%, respectively). 2. Evaluation of kinetic parameters showed that guanosine affected significantly only uptake Vmax (23%). 3. The guanosine withdrawal did not abolish its significant effect on glutamate uptake when 100 or 300 microM glutamate were used (an increase of 66 and 35%, respectively). 4. These results support the hypothesis of a protective role for guanosine during excitotoxic conditions when glutamate levels are enhanced (e.g. brain ischemia and seizures), possibly by activating glutamate uptake. Moreover, our results may contribute to understand the antiexcitotoxic mechanism of guanosine on glutamate transport, giving new information concerning its mechanism of action.
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http://dx.doi.org/10.1007/s10571-005-4939-5 | DOI Listing |
Neurotox Res
January 2025
Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Resveratrol, a natural polyphenol, has shown promising neuroprotective effects in several in vivo and in vitro experimental models. However, the mechanisms by which resveratrol mediates these effects are not fully understood. Glutamate is the major excitatory neurotransmitter in the brain; however, excessive extracellular glutamate levels can affect neural activity in several neurological diseases.
View Article and Find Full Text PDFPhysiol Plant
January 2025
College of Grassland Science and Technology, Sichuan Agricultural University, Chengdu, China.
The gene GAD1 encodes a glutamate decarboxylase, which is a rate-limiting enzyme for the biosynthesis of endogenous γ-aminobutyrate acid (GABA), but a potential role of GAD1 in regulating cadmium (Cd) tolerance needs to be further elucidated in plants. The objective of this study was to investigate Cd tolerance of creeping bentgrass (Agrostis stolonifera) and transgenic yeast (Saccharomyces cerevisiae) or Arabidopsis thaliana overexpressing AsGAD1. The Cd-tolerant creeping bentgrass cultivar LOFTSL-93 accumulated more endogenous GABA in relation to a significant upregulation of AsGAD1 in leaf and root than the Cd-sensitive W66569 in response to Cd stress.
View Article and Find Full Text PDFZhonghua Yi Xue Za Zhi
January 2025
Department of Urology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing100730, China.
To compare the diagnostic value of fluorine 18-labelled prostate-specific membrane antigen (PSMA) PET/CT PRIMARY score and PSMA expression score for clinically significant prostate cancer (csPCa). The data of 70 patients with prostate cancer who underwent radical prostatectomy at Beijing Hospital from February 1, 2019 to February 29, 2024 were retrospectively analyzed. All patients underwent whole body F-PSMA PET/CT examination before surgery and pathological large sections of prostate specimens were made after surgery.
View Article and Find Full Text PDFExtremophiles
January 2025
Division of Natural Sciences, Indiana Wesleyan University, Marion, Indiana, USA.
Rhodothalassium (Rts.) salexigens is a halophilic purple nonsulfur bacterium and the sole species in the genus Rhodothalassium, which is itself the sole genus in the family Rhodothalassiaceae and sole family in the order Rhodothalassiales (class Alphaproteobacteria). The genome of this phylogenetically unique phototroph comprises 3.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Ministry of Agriculture and Rural Affairs, Key Laboratory of Aquatic Animal Immune Technology, Key Laboratory of fishery Drug Development, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China.
Glutamine metabolism is essential for infectious spleen and kidney necrosis virus (ISKNV) replication. Glutaminase 1 (GLS1), the key enzyme of the glutamine metabolism, and c-Myc positively regulate ISKNV infection, while c-Myc is closely correlated with GLS1. However, the regulatory mechanism among ISKNV, c-Myc and glutamine metabolism remains unclear.
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