24 research outputs found

    Determination of endogenous levels of cyclic ADP-ribose in rat tissues

    No full text
    Cyclic ADP-ribose (cADPR) is a potent mediator of calcium mobilization in sea urchin eggs. The cADPR synthesizing enzyme is present not only in the eggs but also in various mammalian tissue extracts. The purpose of this study was to ascertain whether cADPR is a naturally occurring nucleotide in mammalian tissues. Rat tissues were frozen and powdered in liquid N2, followed by extraction with perchloric acid at -10°C. [32P]cADPR was prepared and used as a tracer. The acid extracts were chromatographed on a Mono-Q column and cADPR in the fractions were determined by its ability to release Ca2+ from egg homogenates. That the release was mediated by cADPR and not inositol trisphosphate (IP3) in the extracts was shown by the fact that the homogenates, subsequent to Ca2+ release induced by active fractions, were desensitized to authentic cADPR but not to IP3. Furthermore, the Ca2+ release activity was shown to co-elute with [32P]cADPR. The endogenous level of cADPR determined in rat liver is 3.37 ± 0.64 pmol/mg, in heart is 1.04 ± 0.08 pmol/mg and in brain is 2.75 ± 0.35 pmol/mg. These results indicate cADPR is a naturally occurring nucleotide and suggest that it may be a general second messenger for mobilizing intracellular Ca2+.link_to_subscribed_fulltex

    Dynamic Phosphometabolomic Profiling of Human Tissues and Transgenic Models By O-18-Assisted P-31 Nmr and Mass Spectrometry

    No full text
    Next-generation screening of disease-related metabolomic phenotypes requires monitoring of both metabolite levels and turnover rates. Stable isotope O-18-assisted P-31 nuclear magnetic resonance (NMR) and mass spectrometry uniquely allows simultaneous measurement of phosphometabolite levels and turnover rates in tissue and blood samples. The O-18 labeling procedure is based on the incorporation of one O-18 into Pi from [O-18]H2O with each act of ATP hydrolysis and the distribution of O-18-labeled phosphoryls among phosphate-carrying molecules. This enables simultaneous recording of ATP synthesis and utilization, phosphotransfer fluxes through adenylate kinase, creatine kinase, and glycolytic pathways, as well as mitochondrial substrate shuttle, urea and Krebs cycle activity, glycogen turnover, and intracellular energetic communication. Application of expanded O-18-labeling procedures has revealed significant differences in the dynamics of G-6-P[O-18] (glycolysis), G-3-P[O-18] (substrate shuttle), and G-1-P[O-18] (glycogenolysis) between human and rat atrial myocardium. In human atria, the turnover of G-3-P[O-18], which defects are associated with the sudden death syndrome, was significantly higher indicating a greater importance of substrate shuttling to mitochondria. Phosphometabolomic profiling of transgenic hearts deficient in adenylate kinase (AK1-/-), which altered levels and mutations are associated to human diseases, revealed a stress-induced shift in metabolomic profile with increased CrP[O-18] and decreased G-1-P[O-18] metabolic dynamics. The metabolomic profile of creatine kinase M-CK/ScCKmit-/--deficient hearts is characterized by a higher G-6-[O-18]P turnover rate, G-6-P levels, glycolytic capacity, gamma/beta-phosphoryl of GTP[O-18] turnover, as well as beta-[O-18]ATP and beta-[O-18]ADP turnover, indicating altered glycolytic, guanine nucleotide, and adenylate kinase metabolic flux. Thus, O-18-assisted gas chromatography-mass spectrometry and P-31 NMR provide a suitable platform for dynamic phosphometabolomic profiling of the cellular energetic system enabling prediction and diagnosis of metabolic diseases states.Wo

    sj-docx-1-pmt-10.1177_87551225231224251 – Supplemental material for Endocrinology/Primary Care Pharmacy Collaboration vs Endocrinology Care Alone in Patients With Type 2 Diabetes and A1c >9%

    No full text
    Supplemental material, sj-docx-1-pmt-10.1177_87551225231224251 for Endocrinology/Primary Care Pharmacy Collaboration vs Endocrinology Care Alone in Patients With Type 2 Diabetes and A1c >9% by Courtney R. Fornwald, Giavanna Russo-Alvarez, Kevin M. Pantalone, Elizabeth Zeleznikar, Marcie Parker, Nicole McCorkindale, Robert Butler and Taylor Hermiller in Journal of Pharmacy Technology</p
    corecore