The purpose of the present work was to have a closer view on the changes in the regulation of glycogen synthase (GS) activity by insulin in relationship with the impairment of nonoxidative glucose disposal in human obesity. Obese patients with normal glucose tolerance (12), impaired glucose tolerance (11), diabetes (10), and lean control subjects (15) participated to the study. A euglycemic, hyperinsulinemic clamp was performed and associated with indirect calorimetry. Muscle needle biopsies were taken before and at the end of the 2-hour clamp for measurements of glycogen synthase fractional velocity and total activity. Total GS activity was significantly decreased (P <.05), while its percent activation by insulin was still normal in the obese glucose-tolerant group, and nonoxidative glucose disposal was decreased by 56% (P <.001) and glucose oxidation still normal. Total GS activity was decreased by about 50% (P <.01) and GS was unresponsive to insulin in the glucose-intolerant and diabetic groups. In conclusion, our data show that insulin-stimulated nonoxidative glucose disposal and total glycogen synthase are very early defects observed in obese patients.
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http://dx.doi.org/10.1053/meta.2002.31972 | DOI Listing |
Hepatology
January 2025
Genome Medical Science Project, National Center for Global Health and Medicine, Ichikawa, Japan.
Background Aims: Hepatitis B virus (HBV) leads to severe liver diseases, such as cirrhosis and hepatocellular carcinoma. Identification of host factors that regulate HBV replication can provide new therapeutic targets. The discovery of sodium taurocholate cotransporting polypeptide (NTCP) as an HBV entry receptor has enabled the establishment of hepatic cell lines for analyzing HBV infection and propagation.
View Article and Find Full Text PDFMicroPubl Biol
January 2025
The University of Alabama, Tuscaloosa, AL USA.
Gene model for the ortholog of glycogen synthase ( ) in the May 2017 (Princeton ASM75419v2/DsimGB2) Genome Assembly (GenBank Accession: GCA_000754195.3 ). This ortholog was characterized as part of a developing dataset to study the evolution of the Insulin/insulin-like growth factor signaling pathway (IIS) across the genus using the Genomics Education Partnership gene annotation protocol for Course-based Undergraduate Research Experiences.
View Article and Find Full Text PDFNeurochem Res
January 2025
Department of Pathophysiology, Medical University of Lublin, 20-090, Lublin, Poland.
Methionine sulfoximine (MSO) is a compound originally discovered as a byproduct of agene-based milled flour maturation. MSO irreversibly inhibits the astrocytic enzyme glutamine synthase (GS) but also interferes with the transport of glutamine (Gln) and of glutamate (Glu), and γ-aminobutyric acid (GABA) synthesized within the Glu/Gln-GABA cycle, in this way dysregulating neurotransmission balance in favor of excitation. No wonder that intraperitoneal administration of MSO has long been known to induce behavioral and/or electrographic seizures.
View Article and Find Full Text PDFNeurosci Lett
January 2025
Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan. Electronic address:
Disruption of gut microbiota balance is known to contribute to the development of anxiety; however, it remains unclear whether dysbiosis-induced anxiety involves the glycogen synthase kinase-3β (GSK-3β)/cAMP response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF) pathway and neurogenesis in the ventral hippocampal dentate gyrus (DG). In this study, Male ddY mice were administered an antibacterial cocktail to induce dysbiosis. The dysbiosis model displayed anxiety-like behaviors in the hole-board and elevated plus-maze tests, decreased the phosphorylation levels of GSK-3β (Ser9) and CREB, decreased the expression level of BDNF in the ventral hippocampus, and reduced neurogenesis in the ventral hippocampal DG.
View Article and Find Full Text PDFFront Plant Sci
January 2025
Institute of Food Crops, Hainan Academy of Agricultural Sciences/Hainan Key Laboratory of Crop Genetics and Breeding, Haikou, China.
Introduction: Sweet potato is an important food, feed and industrial raw material, and its tubers are rich in starch, carotenoids and anthocyanins.
Methods: To elucidate the gene expression regulation and metabolic characteristics during the development of sweet potato tubers, transcriptomic and metabolomic analyses were performed on the tubers of three different sweet potato varieties at three developmental stages (70, 100, and 130 days (d)).
Results: RNA-seq analysis revealed that 16,303 differentially expressed genes (DEGs) were divided into 12 clusters according to their expression patterns, and the pathways of each cluster were annotated.
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