Tritiated substrates at tracer levels were incubated with rat hepatocytes plus 10 mM L-lactate, and the yields of tritium in glucose and water, as well as the tritium distribution on C-6 and C-4 of glucose, determined. Substrates of cytosolic type A NAD-linked dehydrogenases showed some preferential labeling of C-6 of glucose (the pathway involving type A malate dehydrogenase), whereas substrates of cytosolic type B NAD-linked dehydrogenases showed some preferential labeling of C-4 of glucose (the pathway involving type B glyceraldehyde-3P dehydrogenase). The results found are consistent with a classical diffusion model of NADH metabolism, and are at odds with the Srivastava hypothesis (based on isolated enzyme studies) which indicated that direct transfer of NADH can occur between many NAD-linked enzymes but only when they are of opposite (A or B) specificity.

Download full-text PDF

Source
http://dx.doi.org/10.1016/0003-9861(91)90079-xDOI Listing

Publication Analysis

Top Keywords

c-4 glucose
8
substrates cytosolic
8
cytosolic type
8
type nad-linked
8
nad-linked dehydrogenases
8
dehydrogenases preferential
8
preferential labeling
8
glucose pathway
8
pathway involving
8
involving type
8

Similar Publications

Phosphoenolpyruvate (PEP) carboxylase (PEPC) has an anaplerotic role in central plant metabolism but also initiates the carbon concentrating mechanism during C photosynthesis. The C PEPC has different binding affinities (K) for PEP (K) and HCO (K), and allosteric regulation by glucose-6-phosphate (G6-P) compared to non-photosynthetic isoforms. These differences are linked to specific changes in amino acids within PEPC.

View Article and Find Full Text PDF

NIR-II Imaging for Tracking the Spatiotemporal Immune Microenvironment in Atherosclerotic Plaques.

ACS Nano

December 2024

Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, Imaging Diagnostic and Interventional Minimally Invasive Institute, The Fifth Affiliated Hospital of Wenzhou Medical University, No 289, Kuocang Road, Lishui 323000, China.

Article Synopsis
  • - The study focuses on how the inflammatory immune microenvironment contributes to atherosclerotic plaque erosion and rupture, using near-infrared-II (NIR-II) fluorescence imaging for monitoring these changes over time.
  • - Three types of NIR-II probes were developed to specifically target different macrophage populations and plaques, allowing precise imaging of atherosclerotic conditions and the roles of M1 and M2 macrophages.
  • - Key findings indicate that M1 macrophages create a harmful inflammatory environment, while M2 macrophages are important for lipid clearance in early plaques, highlighting the significance of macrophage polarization and metabolic changes in atherosclerosis progression.
View Article and Find Full Text PDF

Isosativene and sativene sesquiterpene derivatives from Dendrobium nobile.

Fitoterapia

December 2024

State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, PR China. Electronic address:

Two unusual isosativene sesquiterpene derivatives, named dendronobilol A (1) and dendronobilside A (2), and two unusual sativene sesquiterpene derivatives, named dendronobilsides B (3) and C (4), had been isolated from the stems of Dendrobium nobile. The structures of all the compounds were established using spectroscopic methods and by comparison with literature data, and their absolute configurations were confirmed via single-crystal X-ray diffraction data and electronic circular dichroism (ECD) calculations. Dendronobilol A (1) and dendronobilside A (2) possessed a unique tricyclo[4.

View Article and Find Full Text PDF

Talarmalnoids A-F: Fusicoccane diterpenoids from an arthropod-derived endophytic fungus Talaromyces malicola.

Fitoterapia

December 2024

State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, People's Republic of China. Electronic address:

The metabolites from the endophytic fungus Talaromyces malicola hosted in the gastrointestinal tract of the arthropods Armadillidium vulgare were investigated, and six undescribed fusicoccane diterpenoids, talarmalnoids A-F (1-6), along with three known analogs were isolated. Talarmalnoid C (3) was an unprecedented fusicoccane diterpenoid with two sugar units, i.e.

View Article and Find Full Text PDF
Article Synopsis
  • * Deleting AMPK in atrial tissue shifts metabolism from fatty acid oxidation to pyruvate oxidation, resulting in lower levels of long-chain fatty acyl-CoAs and reduced expression of proteins that help take in and process fatty acids.
  • * The study shows that AMPK is essential for maintaining atrial metabolic balance, and its deletion disrupts the PGC1-α/PPARα signaling pathway, which may lead to heart remodeling and increased risk of arrhythmias.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!