We studied the binding of [3H]nitrobenzylthioinosine (NBMPR) and the uptake of [3H]formycin B by the es (equilibrative inhibitor-sensitive) nucleoside transporter of Madin Darby Canine Kidney (MDCK) cells. NBMPR inhibited [3H]formycin B uptake with a Ki of 2.7+/-0.6 nM, and [3H]NBMPR had a KD of 1.3+/-0.3 nM for binding to these cells; these values are significantly higher than those obtained in human and mouse cell models. In contrast, other recognized es inhibitors, such as dipyridamole, were significantly more effective as inhibitors of [3H]NBMPR binding and [3H]formycin B uptake by MDCK cells relative to that seen for human cells. We isolated a cDNA encoding the canine es nucleoside transporter (designated cENT1), and assessed its function by stable expression in nucleoside transport deficient PK15NTD cells. The PK15-cENT1 cells displayed inhibitor sensitivities that were comparable to those obtained for the endogenous es nucleoside transporter in MDCK cells. These data indicate that the dog es/ENT1 transporter has distinctive inhibitor binding characteristics, and that these characteristics are a function of the protein structure as opposed to the environment in which it is expressed.
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http://dx.doi.org/10.1016/j.ejphar.2004.03.026 | DOI Listing |
Cell Mol Life Sci
January 2025
Institute of Endotypes in Oncology, Metabolism, and Immunology, National Research Council, Via Pietro Castellino 111, Naples, Italy.
Breast cancer represents the primary cause of death of women under 65 in developed countries, due to the acquisition of multiple drug resistance mechanisms. The PI3K/AKT pathway is one of the major regulating mechanisms altered during the development of endocrine resistance and inhibition of steps in this signalling pathway are adopted as a key strategy to overcome this issue. ADP-ribosylation is a post-translational modification catalysed by PARP enzymes that regulates essential cellular processes, often altered in diseases.
View Article and Find Full Text PDFChin J Integr Med
January 2025
Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
Objective: To explore the neuroprotective effects of Xuefu Zhuyu Decoction (XFZYD) based on in vivo and metabolomics experiments.
Methods: Traumatic brain injury (TBI) was induced via a controlled cortical impact (CCI) method. Thirty rats were randomly divided into 3 groups (10 for each): sham, CCI and XFZYD groups (9 g/kg).
Int J Mol Sci
December 2024
Atherothrombosis Research Centre/Laboratory of Biochemistry, Department of Chemistry, University of Ioannina, 451 10 Ioannina, Greece.
Ticagrelor, a reversible platelet P2Y receptor antagonist, exerts various pleiotropic actions, some of which are at least partially mediated through adenosine. We studied the ticagrelor and adenosine effect on the angiogenic properties of progenitor CD34-derived endothelial colony-forming cells (ECFCs). Angiogenesis studies were performed in vitro using capillary-like tube formation and spheroid-based angiogenesis assays.
View Article and Find Full Text PDFJ Hematol Oncol
January 2025
Department of Radiation Oncology, Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, Henan, People's Republic of China.
Background: Targeting glucose uptake by glucose transporter (GLUT) inhibitors is a therapeutic opportunity, but efforts on GLUT inhibitors have not been successful in the clinic and the underlying mechanism remains unclear. We aim to identify the key metabolic changes responsible for cancer cell survival from glucose limitation and elucidate its mechanism.
Methods: The level of phosphorylated YAP was analyzed with Western blotting and Phos-tag immunoblotting.
Bioorg Chem
January 2025
Good Clinical Practice Development, Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China. Electronic address:
Inhibition of human concentrative nucleoside transporter 2 (CNT2) could suppress increases in serum urate levels derived from dietary purines. However, the structural basis for substrate recognition of CNT2 is still unknown and only a few inhibitors have been reported. In this study, a homology model of CNT2 was constructed and residues T315, E316, N426, N491, E492, F536 and N538 were identified as binding sites for adenosine through site-directed mutagenesis and a H-adenosine uptake assay.
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