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Luo Y, Qi X, Zhang Z, Zhang J, Li B, Shu T, Li X, Hu H, Li J, Tang Q, Zhou Y, Wang M, Fan T, Guo W, Liu Y, Zhang J, Pang J, Yang P, Gao R, Chen W, Yan C, Xing Y, Du W, Wang J, Wang C. Inactivation of Malic Enzyme 1 in Endothelial Cells Alleviates Pulmonary Hypertension. Circulation 2024; 149:1354-1371. [PMID: 38314588 DOI: 10.1161/circulationaha.123.067579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Accepted: 01/10/2024] [Indexed: 02/06/2024]
Abstract
BACKGROUND Pulmonary hypertension (PH) is a progressive cardiopulmonary disease with a high mortality rate. Although growing evidence has revealed the importance of dysregulated energetic metabolism in the pathogenesis of PH, the underlying cellular and molecular mechanisms are not fully understood. In this study, we focused on ME1 (malic enzyme 1), a key enzyme linking glycolysis to the tricarboxylic acid cycle. We aimed to determine the role and mechanistic action of ME1 in PH. METHODS Global and endothelial-specific ME1 knockout mice were used to investigate the role of ME1 in hypoxia- and SU5416/hypoxia (SuHx)-induced PH. Small hairpin RNA and ME1 enzymatic inhibitor (ME1*) were used to study the mechanism of ME1 in pulmonary artery endothelial cells. Downstream key metabolic pathways and mediators of ME1 were identified by metabolomics analysis in vivo and ME1-mediated energetic alterations were examined by Seahorse metabolic analysis in vitro. The pharmacological effect of ME1* on PH treatment was evaluated in PH animal models induced by SuHx. RESULTS We found that ME1 protein level and enzymatic activity were highly elevated in lung tissues of patients and mice with PH, primarily in vascular endothelial cells. Global knockout of ME1 protected mice from developing hypoxia- or SuHx-induced PH. Endothelial-specific ME1 deletion similarly attenuated pulmonary vascular remodeling and PH development in mice, suggesting a critical role of endothelial ME1 in PH. Mechanistic studies revealed that ME1 inhibition promoted downstream adenosine production and activated A2AR-mediated adenosine signaling, which leads to an increase in nitric oxide generation and a decrease in proinflammatory molecule expression in endothelial cells. ME1 inhibition activated adenosine production in an ATP-dependent manner through regulating malate-aspartate NADH (nicotinamide adenine dinucleotide plus hydrogen) shuttle and thereby balancing oxidative phosphorylation and glycolysis. Pharmacological inactivation of ME1 attenuated the progression of PH in both preventive and therapeutic settings by promoting adenosine production in vivo. CONCLUSIONS Our findings indicate that ME1 upregulation in endothelial cells plays a causative role in PH development by negatively regulating adenosine production and subsequently dysregulating endothelial functions. Our findings also suggest that ME1 may represent as a novel pharmacological target for upregulating protective adenosine signaling in PH therapy.
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Affiliation(s)
- Ya Luo
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
- Department of Pulmonary and Critical Care Medicine, Xinqiao Hospital, Third Military Medical University, Chongqing, China (Y.L.)
| | - Xianmei Qi
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Zhenxi Zhang
- State Key Laboratory of Common Mechanism Research for Major Diseases (Z.Z., W.D.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Jiawei Zhang
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Bolun Li
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Ting Shu
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Xiaona Li
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Huiyuan Hu
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Jinqiu Li
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Qihao Tang
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Yitian Zhou
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Mingyao Wang
- Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, China-Japan Friendship Hospital, Beijing, China (M.W., C.W.)
| | - Tianfei Fan
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Wenjun Guo
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Ying Liu
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Jin Zhang
- Department of Thoracic Surgery, China-Japan Friendship Hospital, Beijing, China (J.Z.)
| | - Junling Pang
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Peiran Yang
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Ran Gao
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Wenhui Chen
- Department of Lung Transplantation, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, China-Japan Friendship Hospital, Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, Beijing, China (W.C.)
| | - Chen Yan
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY (C.Y.)
| | - Yanjiang Xing
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Wenjing Du
- State Key Laboratory of Common Mechanism Research for Major Diseases (Z.Z., W.D.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Jing Wang
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
| | - Chen Wang
- State Key Laboratory of Respiratory Health and Multimorbidity (Y.L., X.Q., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., J.P., P.Y., Y.X., J.W., C.W.)
- Haihe Laboratory of Cell Ecosystem, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China (Y.L., X.Q., Z.Z., J.Z., B.L., T.S., X.L., H.H., J.L., Q.T., Y.Z., T.F., W.G., Y.L., J.P., P.Y., R.G., Y.X., W.D., J.W., C.W.)
- Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, China-Japan Friendship Hospital, Beijing, China (M.W., C.W.)
- Chinese Academy of Engineering, Beijing, China (C.W.)
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Ito T, Kubo Y, Akanuma SI, Hosoya KI. Functional characteristics of 3'-azido-3'-deoxythymidine transport at the blood-testis barrier. Int J Pharm 2022; 625:122044. [PMID: 35902057 DOI: 10.1016/j.ijpharm.2022.122044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/28/2022] [Accepted: 07/19/2022] [Indexed: 11/18/2022]
Abstract
3'-Azido-3'-deoxythymidine (AZT), an antiretroviral drug, is often adopted in the therapy for human immunodeficiency virus (HIV) infection, and the characteristics of AZT transport at the blood-testis barrier (BTB) were investigated in this study. In the integration plot analysis that evaluates the transport activity in vivo, the apparent influx clearance of [3H]AZT was significantly greater than that of [14C]D-mannitol, a non-permeable paracellular transport marker. In the uptake study in vitro with TM4 cells derived from mouse Sertoli cells, [3H]AZT uptake exhibited a time- and concentration-dependent manner, of which Km and Vmax values being 20.3 µM and 102 pmol/(min·mg protein), respectively. In the inhibition analysis, [3H]AZT uptake was not affected by extracellular inorganics and some substrates of transporters putatively involved in AZT transport. In the further inhibition analyses to elucidate the characteristics of AZT transport, [3H]AZT uptake was strongly reduced in the presence of several nucleosides, that are categorized as 2'-deoxynucleosides with pyrimidine, whereas little effect on [3H]AZT uptake was exhibited in the presence of other nucleosides, nucleobases, and antiretrovirals. These results suggest the influx transport of AZT from the circulating blood to the testis, and the involvement of carrier-mediated process at the BTB, which selectively recognizes 2'-deoxynucleosides with a pyrimidine base.
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Affiliation(s)
- Takeru Ito
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Yoshiyuki Kubo
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; Laboratory of Drug Disposition & Pharmacokinetics, Faculty of Pharma-Sciences, Teikyo University, Kaga 2-11-1, Tokyo 173-8605, Japan.
| | - Shin-Ichi Akanuma
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Ken-Ichi Hosoya
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
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3
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Bednarska-Szczepaniak K, Mieczkowski A, Kierozalska A, Pavlović Saftić D, Głąbała K, Przygodzki T, Stańczyk L, Karolczak K, Watała C, Rao H, Gao ZG, Jacobson KA, Leśnikowski ZJ. Synthesis and evaluation of adenosine derivatives as A 1, A 2A, A 2B and A 3 adenosine receptor ligands containing boron clusters as phenyl isosteres and selective A 3 agonists. Eur J Med Chem 2021; 223:113607. [PMID: 34171656 PMCID: PMC8448983 DOI: 10.1016/j.ejmech.2021.113607] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 01/30/2023]
Abstract
A series of adenosine and 2'-deoxyadenosine pairs modified with a 1,12-dicarba-closo-dodecaborane cluster or alternatively with a phenyl group at the same position was synthesized, and their affinity was determined at A1, A2A, A2B and A3 adenosine receptors (ARs). While AR affinity differences were noted, a general tendency to preferentially bind A3 AR over other ARs was observed for most tested ligands. In particular, 5'-ethylcarbamoyl-N6-(3-phenylpropyl)adenosine (18), N6-(3-phenylpropyl)-2-chloroadenosine (24) and N6-(3-phenylpropyl)adenosine (40) showed nanomolar A3 affinity (Ki 4.5, 6.4 and 7.5 nM, respectively). Among the boron cluster-containing compounds, the highest A3 affinity (Ki 206 nM) was for adenosine derivative 41 modified at C2. In the matched molecular pairs, analogs bearing boron clusters were found to show lower binding affinity for adenosine receptors than the corresponding phenyl analogs. Nevertheless, interestingly, several boron cluster modified adenosine ligands showed significantly higher A3 receptor selectivity than the corresponding phenyl analogs: 7vs. 8, 15vs. 16, 17vs. 18.
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Affiliation(s)
| | - Adam Mieczkowski
- Laboratory of Biological Chemistry of Metal Ions, Institute of Biochemistry and Biophysics PAS, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Aleksandra Kierozalska
- Laboratory of Medicinal Chemistry, Institute of Medical Biology PAS, Lodowa 106, 92-232, Łódź, Poland
| | - Dijana Pavlović Saftić
- Laboratory of Medicinal Chemistry, Institute of Medical Biology PAS, Lodowa 106, 92-232, Łódź, Poland
| | - Konrad Głąbała
- Laboratory of Medicinal Chemistry, Institute of Medical Biology PAS, Lodowa 106, 92-232, Łódź, Poland
| | - Tomasz Przygodzki
- Department of Haemostatic Disorders, Medical University of Lodz, 6/8 Mazowiecka St. 92-215, Lodz, Poland
| | - Lidia Stańczyk
- Department of Haemostatic Disorders, Medical University of Lodz, 6/8 Mazowiecka St. 92-215, Lodz, Poland
| | - Kamil Karolczak
- Department of Haemostatic Disorders, Medical University of Lodz, 6/8 Mazowiecka St. 92-215, Lodz, Poland
| | - Cezary Watała
- Department of Haemostatic Disorders, Medical University of Lodz, 6/8 Mazowiecka St. 92-215, Lodz, Poland
| | - Harsha Rao
- Laboratory of Bioorganic Chemistry and Molecular Recognition Section, National Institute of Diabetes & Digestive & Kidney Diseases, NIH, Bethesda, MD, 20892-0810, USA
| | - Zhan-Guo Gao
- Laboratory of Bioorganic Chemistry and Molecular Recognition Section, National Institute of Diabetes & Digestive & Kidney Diseases, NIH, Bethesda, MD, 20892-0810, USA
| | - Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry and Molecular Recognition Section, National Institute of Diabetes & Digestive & Kidney Diseases, NIH, Bethesda, MD, 20892-0810, USA
| | - Zbigniew J Leśnikowski
- Laboratory of Medicinal Chemistry, Institute of Medical Biology PAS, Lodowa 106, 92-232, Łódź, Poland.
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Szeri F, Niaziorimi F, Donnelly S, Orndorff J, van de Wetering K. Generation of fully functional fluorescent fusion proteins to gain insights into ABCC6 biology. FEBS Lett 2021; 595:799-810. [PMID: 33058196 PMCID: PMC7987643 DOI: 10.1002/1873-3468.13957] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/04/2020] [Accepted: 09/29/2020] [Indexed: 12/18/2022]
Abstract
ABCC6 mediates release of ATP from hepatocytes into the blood. Extracellularly, ATP is converted into the mineralization inhibitor pyrophosphate. Consequently, inactivating mutations in ABCC6 give low plasma pyrophosphate and underlie the ectopic mineralization disorder pseudoxanthoma elasticum. How ABCC6 mediates cellular ATP release is still unknown. Fluorescent ABCC6 fusion proteins would allow mechanistic studies, but fluorophores attached to the ABCC6 N- or C-terminus result in intracellular retention and degradation. Here we describe that intramolecular introduction of fluorophores yields fully functional ABCC6 fusion proteins. A corresponding ABCC6 variant in which the catalytic glutamate of the second nucleotide binding domain was mutated, correctly routed to the plasma membrane but was inactive. Finally, N-terminal His10 or FLAG tags did not affect activity of the fusion proteins, allowing their purification for biochemical characterization.
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Affiliation(s)
- Flora Szeri
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, 19107, Philadelphia (PA), USA
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary (current address)
| | - Fatemeh Niaziorimi
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, 19107, Philadelphia (PA), USA
| | - Sylvia Donnelly
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, 19107, Philadelphia (PA), USA
| | - Joseph Orndorff
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, 19107, Philadelphia (PA), USA
| | - Koen van de Wetering
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, 19107, Philadelphia (PA), USA
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Procopio MC, Lauro R, Nasso C, Carerj S, Squadrito F, Bitto A, Di Bella G, Micari A, Irrera N, Costa F. Role of Adenosine and Purinergic Receptors in Myocardial Infarction: Focus on Different Signal Transduction Pathways. Biomedicines 2021; 9:biomedicines9020204. [PMID: 33670488 PMCID: PMC7922652 DOI: 10.3390/biomedicines9020204] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 02/15/2021] [Indexed: 12/24/2022] Open
Abstract
Myocardial infarction (MI) is a dramatic event often caused by atherosclerotic plaque erosion or rupture and subsequent thrombotic occlusion of a coronary vessel. The low supply of oxygen and nutrients in the infarcted area may result in cardiomyocytes necrosis, replacement of intact myocardium with non-contractile fibrous tissue and left ventricular (LV) function impairment if blood flow is not quickly restored. In this review, we summarized the possible correlation between adenosine system, purinergic system and Wnt/β-catenin pathway and their role in the pathogenesis of cardiac damage following MI. In this context, several pathways are involved and, in particular, the adenosine receptors system shows different interactions between its members and purinergic receptors: their modulation might be effective not only for a normal functional recovery but also for the treatment of heart diseases, thus avoiding fibrosis, reducing infarcted area and limiting scaring. Similarly, it has been shown that Wnt/β catenin pathway is activated following myocardial injury and its unbalanced activation might promote cardiac fibrosis and, consequently, LV systolic function impairment. In this regard, the therapeutic benefits of Wnt inhibitors use were highlighted, thus demonstrating that Wnt/β-catenin pathway might be considered as a therapeutic target to prevent adverse LV remodeling and heart failure following MI.
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Affiliation(s)
- Maria Cristina Procopio
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Rita Lauro
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Chiara Nasso
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Scipione Carerj
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Francesco Squadrito
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Alessandra Bitto
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Gianluca Di Bella
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
| | - Antonio Micari
- Department of Biomedical and Dental Sciences and Morphological and Functional Imaging, University of Messina, A.O.U. Policlinic “G. Martino”, 98165 Messina, Italy;
| | - Natasha Irrera
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
- Correspondence: ; Tel.: +39-090-221-3093; Fax: +39-090-221-23-81
| | - Francesco Costa
- Department of Clinical and Experimental Medicine, University of Messina, 98165 Messina, Italy; (M.C.P.); (R.L.); (C.N.); (S.C.); (F.S.); (A.B.); (G.D.B.); (F.C.)
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6
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Gaudry M, Vairo D, Marlinge M, Gaubert M, Guiol C, Mottola G, Gariboldi V, Deharo P, Sadrin S, Maixent JM, Fenouillet E, Ruf J, Guieu R, Paganelli F. Adenosine and Its Receptors: An Expected Tool for the Diagnosis and Treatment of Coronary Artery and Ischemic Heart Diseases. Int J Mol Sci 2020; 21:ijms21155321. [PMID: 32727116 PMCID: PMC7432452 DOI: 10.3390/ijms21155321] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/15/2020] [Accepted: 07/21/2020] [Indexed: 12/14/2022] Open
Abstract
Adenosine is an endogenous nucleoside which strongly impacts the cardiovascular system. Adenosine is released mostly by endothelial cells and myocytes during ischemia or hypoxia and greatly regulates the cardiovascular system via four specific G-protein-coupled receptors named A1R, A2AR, A2BR, and A3R. Among them, A2 subtypes are strongly expressed in coronary tissues, and their activation increases coronary blood flow via the production of cAMP in smooth muscle cells. A2A receptor modulators are an opportunity for intense research by the pharmaceutical industry to develop new cardiovascular therapies. Most innovative therapies are mediated by the modulation of adenosine release and/or the activation of the A2A receptor subtypes. This review aims to focus on the specific exploration of the adenosine plasma level and its relationship with the A2A receptor, which seems a promising biomarker for a diagnostic and/or a therapeutic tool for the screening and management of coronary artery disease. Finally, a recent class of selective adenosine receptor ligands has emerged, and A2A receptor agonists/antagonists are useful tools to improve the management of patients suffering from coronary artery disease.
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Affiliation(s)
- Marine Gaudry
- Department of Vascular Surgery, Timone Hospital, F-13008 Marseille, France;
| | - Donato Vairo
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
| | - Marion Marlinge
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
- Laboratory of Biochemistry, Timone Hospital, F-13008 Marseille, France
| | - Melanie Gaubert
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
| | - Claire Guiol
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
| | - Giovanna Mottola
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
- Laboratory of Biochemistry, Timone Hospital, F-13008 Marseille, France
| | - Vlad Gariboldi
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
- Department of Cardiac Surgery, Timone Hospital, F-13008 Marseille, France
| | - Pierre Deharo
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
- Department of Cardiology, Timone Hospital, F-13008 Marseille, France
| | | | - Jean Michel Maixent
- Unité de Recherche Clinique Pierre Deniker (URC C.S. 10587) Centre Hospitalier Henri Laborit, 86000 Poitiers, France
- I.A.P.S. Equipe Emergeante, Université de Toulon, 83957 Toulon-La Garde, UFR S.F.A., F-86073 Poitiers, France
- Correspondence: (J.M.M.); (F.P.)
| | - Emmanuel Fenouillet
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
| | - Jean Ruf
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
| | - Regis Guieu
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
- Laboratory of Biochemistry, Timone Hospital, F-13008 Marseille, France
| | - Franck Paganelli
- C2VN, INSERM, INRA, Aix-Marseille University, F-13015 Marseille, France; (D.V.); (M.M.); (M.G.); (C.G.); (G.M.); (V.G.); (P.D.); (E.F.); (J.R.); (R.G.)
- Department of Cardiology, Nord Hospital, ARCHANTEC, F-13015 Marseille, France
- Correspondence: (J.M.M.); (F.P.)
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7
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Purines: From Diagnostic Biomarkers to Therapeutic Agents in Brain Injury. Neurosci Bull 2020; 36:1315-1326. [PMID: 32542580 DOI: 10.1007/s12264-020-00529-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 03/30/2020] [Indexed: 12/12/2022] Open
Abstract
The purines constitute a family of inter-related compounds that serve a broad range of important intracellular and extracellular biological functions. In particular, adenosine triphosphate (ATP) and its metabolite and precursor, adenosine, regulate a wide variety of cellular and systems-level physiological processes extending from ATP acting as the cellular energy currency, to the adenosine arising from the depletion of cellular ATP and responding to reduce energy demand and hence to preserve ATP during times of metabolic stress. This inter-relationship provides opportunities for both the diagnosis of energy depletion during conditions such as stroke, and the replenishment of ATP after such events. In this review we address these opportunities and the broad potential of purines as diagnostics and restorative agents.
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8
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Adenosine and the Cardiovascular System: The Good and the Bad. J Clin Med 2020; 9:jcm9051366. [PMID: 32384746 PMCID: PMC7290927 DOI: 10.3390/jcm9051366] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 12/18/2022] Open
Abstract
Adenosine is a nucleoside that impacts the cardiovascular system via the activation of its membrane receptors, named A1R, A2AR, A2BR and A3R. Adenosine is released during hypoxia, ischemia, beta-adrenergic stimulation or inflammation and impacts heart rhythm and produces strong vasodilation in the systemic, coronary or pulmonary vascular system. This review summarizes the main role of adenosine on the cardiovascular system in several diseases and conditions. Adenosine release participates directly in the pathophysiology of atrial fibrillation and neurohumoral syncope. Adenosine has a key role in the adaptive response in pulmonary hypertension and heart failure, with the most relevant effects being slowing of heart rhythm, coronary vasodilation and decreasing blood pressure. In other conditions, such as altitude or apnea-induced hypoxia, obstructive sleep apnea, or systemic hypertension, the adenosinergic system activation appears in a context of an adaptive response. Due to its short half-life, adenosine allows very rapid adaptation of the cardiovascular system. Finally, the effects of adenosine on the cardiovascular system are sometimes beneficial and other times harmful. Future research should aim to develop modulating agents of adenosine receptors to slow down or conversely amplify the adenosinergic response according to the occurrence of different pathologic conditions.
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9
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Soslau G. Extracellular adenine compounds within the cardiovascular system: Their source, metabolism and function. MEDICINE IN DRUG DISCOVERY 2019. [DOI: 10.1016/j.medidd.2020.100018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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10
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Song A, Zhang Y, Han L, Yegutkin GG, Liu H, Sun K, D'Alessandro A, Li J, Karmouty-Quintana H, Iriyama T, Weng T, Zhao S, Wang W, Wu H, Nemkov T, Subudhi AW, Jameson-Van Houten S, Julian CG, Lovering AT, Hansen KC, Zhang H, Bogdanov M, Dowhan W, Jin J, Kellems RE, Eltzschig HK, Blackburn M, Roach RC, Xia Y. Erythrocytes retain hypoxic adenosine response for faster acclimatization upon re-ascent. Nat Commun 2017; 8:14108. [PMID: 28169986 PMCID: PMC5309698 DOI: 10.1038/ncomms14108] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 11/29/2016] [Indexed: 12/19/2022] Open
Abstract
Faster acclimatization to high altitude upon re-ascent is seen in humans; however, the molecular basis for this enhanced adaptive response is unknown. We report that in healthy lowlanders, plasma adenosine levels are rapidly induced by initial ascent to high altitude and achieved even higher levels upon re-ascent, a feature that is positively associated with quicker acclimatization. Erythrocyte equilibrative nucleoside transporter 1 (eENT1) levels are reduced in humans at high altitude and in mice under hypoxia. eENT1 deletion allows rapid accumulation of plasma adenosine to counteract hypoxic tissue damage in mice. Adenosine signalling via erythrocyte ADORA2B induces PKA phosphorylation, ubiquitination and proteasomal degradation of eENT1. Reduced eENT1 resulting from initial hypoxia is maintained upon re-ascent in humans or re-exposure to hypoxia in mice and accounts for erythrocyte hypoxic memory and faster acclimatization. Our findings suggest that targeting identified purinergic-signalling network would enhance the hypoxia adenosine response to counteract hypoxia-induced maladaptation. Humans that reach high altitude soon after the first ascent show faster adaptation to hypoxia. Song et al. show that this adaptive response relies on decreased red blood cell uptake of plasma adenosine due to reduced levels of nucleoside transporter ENT1 resulting from coordinated adenosine generation by ectonucleotidase CD73 and activation of A2B receptors.
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Affiliation(s)
- Anren Song
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Yujin Zhang
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Leng Han
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | | | - Hong Liu
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Kaiqi Sun
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado, Aurora, Colorado 80045, USA
| | - Jessica Li
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Harry Karmouty-Quintana
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Takayuki Iriyama
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655, Japan
| | - Tingting Weng
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Shushan Zhao
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, 410008 Hunan, China
| | - Wei Wang
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Department of Nephrology, Xiangya Hospital, Central South University, Changsha, 410008 Hunan, China
| | - Hongyu Wu
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Travis Nemkov
- Altitude Research Center, Department of Emergency Medicine University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Andrew W Subudhi
- Altitude Research Center, Department of Emergency Medicine University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Sonja Jameson-Van Houten
- Altitude Research Center, Department of Emergency Medicine University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Colleen G Julian
- Altitude Research Center, Department of Emergency Medicine University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Andrew T Lovering
- Altitude Research Center, Department of Emergency Medicine University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Kirk C Hansen
- Department of Biochemistry and Molecular Genetics, University of Colorado, Aurora, Colorado 80045, USA
| | - Hong Zhang
- Department of Pathology, MD Anderson Cancer Center, Houston, Texas 77030, USA
| | - Mikhail Bogdanov
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - William Dowhan
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Jianping Jin
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Rodney E Kellems
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Holger K Eltzschig
- Organ Protection Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Michael Blackburn
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA
| | - Robert C Roach
- Altitude Research Center, Department of Emergency Medicine University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Yang Xia
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.,Department of Nephrology, Xiangya Hospital, Central South University, Changsha, 410008 Hunan, China
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11
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Burnstock G. Blood cells: an historical account of the roles of purinergic signalling. Purinergic Signal 2015; 11:411-34. [PMID: 26260710 PMCID: PMC4648797 DOI: 10.1007/s11302-015-9462-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 12/17/2022] Open
Abstract
The involvement of purinergic signalling in the physiology of erythrocytes, platelets and leukocytes was recognised early. The release of ATP and the expression of purinoceptors and ectonucleotidases on erythrocytes in health and disease are reviewed. The release of ATP and ADP from platelets and the expression and roles of P1, P2Y(1), P2Y(12) and P2X1 receptors on platelets are described. P2Y(1) and P2X(1) receptors mediate changes in platelet shape, while P2Y(12) receptors mediate platelet aggregation. The changes in the role of purinergic signalling in a variety of disease conditions are considered. The successful use of P2Y(12) receptor antagonists, such as clopidogrel and ticagrelor, for the treatment of thrombosis, myocardial infarction and stroke is discussed.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK.
- Department of Pharmacology and Therapeutics, The University of Melbourne, Melbourne, Australia.
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12
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Wootten D, Christopoulos A, Sexton PM. Emerging paradigms in GPCR allostery: implications for drug discovery. Nat Rev Drug Discov 2013; 12:630-44. [PMID: 23903222 DOI: 10.1038/nrd4052] [Citation(s) in RCA: 350] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Allosteric ligands bind to G protein-coupled receptors (GPCRs; also known as seven-transmembrane receptors) at sites that are distinct from the sites to which endogenous ligands bind. The existence of allosteric ligands has enriched the ways in which the functions of GPCRs can be manipulated for potential therapeutic benefit, yet the complexity of their actions provides both challenges and opportunities for drug screening and development. Converging avenues of research in areas such as biased signalling by allosteric ligands and the mechanisms by which allosteric ligands modulate the effects of diverse endogenous ligands have provided new insights into how interactions between allosteric ligands and GPCRs could be exploited for drug discovery. These new findings have the potential to alter how screening for allosteric drugs is performed and may increase the chances of success in the development of allosteric modulators as clinical lead compounds.
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Affiliation(s)
- Denise Wootten
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Melbourne, Victoria 3052, Australia
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13
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Maes SS, Pype S, Hoffmann VL, Biermans M, Meert TF. Antihyperalgesic activity of nucleoside transport inhibitors in models of inflammatory pain in guinea pigs. J Pain Res 2012; 5:391-400. [PMID: 23091396 PMCID: PMC3474157 DOI: 10.2147/jpr.s35108] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Background and methods The role of the endogenous purine nucleoside, adenosine, in nociception is well established. Inhibition of the equilibrative nucleoside transporter (ENT1) prevents adenosine uptake into cells, and could therefore enhance the antinociceptive properties of adenosine. The effects of ENT1 inhibition were studied in two animal models of inflammatory pain. Analgesic activity was assessed in a complete Freund’s adjuvant (CFA)-induced and carrageenan-induced mechanical and thermal hyperalgesia model in the guinea pig. Results Draflazine, dipyridamole, dilazep, lidoflazine, soluflazine, and KF24345 showed efficacy in the CFA thermal hyperalgesia model. Draflazine, the most potent compound in this test, was further characterized in the CFA model of mechanical hyperalgesia and the carrageenan inflammation model of thermal and mechanical hyperalgesia, where it completely reversed the hypersensitivity. The antihyperalgesic effects of draflazine (10 mg/kg, administered subcutaneously) were attenuated by the A1 receptor antagonist, cyclopentyltheophylline (5–40 mg/kg, administered intraperitoneally), by the nonselective adenosine antagonist, caffeine (10–40 mg/kg intraperitoneally), and by the A2 antagonist, DMPX (10 mg/kg administered intraperitoneally). Conclusion ENT1 inhibition is an effective way of reversing mechanical and thermal inflammatory hyperalgesia in the guinea pig, and these effects are mediated by enhancement of endogenous adenosine levels. Both A1 and A2 adenosine receptor subtypes are likely to be involved.
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Affiliation(s)
- Sabine S Maes
- CNS Discovery Research, Pain and Neurology, Johnson & Johnson Pharmaceutical Research and Development, a Division of Janssen Pharmaceutica, Beerse, Belgium ; Department of Anaesthesiology, University Hospital Antwerp, Edegem, Belgium
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14
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Wootten D, Savage EE, Valant C, May LT, Sloop KW, Ficorilli J, Showalter AD, Willard FS, Christopoulos A, Sexton PM. Allosteric modulation of endogenous metabolites as an avenue for drug discovery. Mol Pharmacol 2012; 82:281-90. [PMID: 22576254 DOI: 10.1124/mol.112.079319] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are the largest family of cell surface receptors and a key drug target class. Recently, allosteric drugs that can co-bind with and modulate the activity of the endogenous ligand(s) for the receptor have become a major focus of the pharmaceutical and biotechnology industry for the development of novel GPCR therapeutic agents. This class of drugs has distinct properties compared with drugs targeting the endogenous (orthosteric) ligand-binding site that include the ability to sculpt cellular signaling and to respond differently in the presence of discrete orthosteric ligands, a behavior termed "probe dependence." Here, using cell signaling assays combined with ex vivo and in vivo studies of insulin secretion, we demonstrate that allosteric ligands can cause marked potentiation of previously "inert" metabolic products of neurotransmitters and peptide hormones, a novel consequence of the phenomenon of probe dependence. Indeed, at the muscarinic M(2) receptor and glucagon-like peptide 1 (GLP-1) receptor, allosteric potentiation of the metabolites, choline and GLP-1(9-36)NH(2), respectively, was ~100-fold and up to 200-fold greater than that seen with the physiological signaling molecules acetylcholine and GLP-1(7-36)NH(2). Modulation of GLP-1(9-36)NH(2) was also demonstrated in ex vivo and in vivo assays of insulin secretion. This work opens up new avenues for allosteric drug discovery by directly targeting modulation of metabolites, but it also identifies a behavior that could contribute to unexpected clinical outcomes if interaction of allosteric drugs with metabolites is not part of their preclinical assessment.
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Affiliation(s)
- Denise Wootten
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
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15
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HPLC assay with UV detection for determination of RBC purine nucleotide concentrations and application for biomarker study in vivo. J Pharm Biomed Anal 2008; 47:377-82. [PMID: 18295998 DOI: 10.1016/j.jpba.2008.01.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 01/07/2008] [Accepted: 01/15/2008] [Indexed: 11/22/2022]
Abstract
ATP and other purine nucleotides are important biomarkers for ischemia and may have considerable potential as targets for management of ischemic heart disease and stroke. The main objective of the study is to develop a rapid HPLC assay, which has adequate sensitivity and specificity for measuring concentrations of ATP, ADP, AMP, GTP, GDP and GMP in erythrocytes (RBC). The assays used ion-pair chromatography coupled with ultraviolet detection at 254 nm to separate and detect the purine nucleotides. Using 50-100 microL of RBC lysate as blank biologic matrix, the assay was linear from 100 to 2000 microg/mL for ATP and ADP, and 20-400 microg/mL for AMP, GTP, and GDP with coefficients of determination (r(2)) >0.99. GDP and GMP were not measurable in the study because of low concentrations and interference from endogenous materials, respectively. The intra-assay and inter-assay variations over a period of 1 year were less than 10% and 20%, respectively for most of the nucleotides. The assay was successfully applied to two pilot biomarker studies to measure RBC concentrations of the purine nucleotides in rats under restraining and exercise conditions. Preliminary results showed that the RBC concentrations of ATP and GTP were higher in the spontaneously hypertensive rats (SHR) compared to the Sprague-Dawley (SD) rats, and that exercise increased RBC concentrations of ATP in rats treated with the calcium channel blocker diltiazem.
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16
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Guieu R, Sampieri F, Bechis G, Halimi G, Dussol B, Berland Y, Sampol J, Rochat H. DEVELOPMENT OF AN HPLC/DIODE ARRAY DETECTOR METHOD FOR THE DETERMINATION OF HUMAN PLASMA ADENOSINE CONCENTRATIONS. J LIQ CHROMATOGR R T 2006. [DOI: 10.1081/jlc-100101769] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | | | | | | | - B. Dussol
- a Centre d'Investigation Clinique , Hôpital Sainte Marguerite , Service de Néphrologie, Bd. Sainte Marguerite, Marseille , 13009 , France
| | - Y. Berland
- a Centre d'Investigation Clinique , Hôpital Sainte Marguerite , Service de Néphrologie, Bd. Sainte Marguerite, Marseille , 13009 , France
| | - J. Sampol
- a Centre d'Investigation Clinique , Hôpital Sainte Marguerite , Service de Néphrologie, Bd. Sainte Marguerite, Marseille , 13009 , France
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17
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Dudzinska W, Hlynczak AJ, Skotnicka E, Suska M. The purine metabolism of human erythrocytes. BIOCHEMISTRY (MOSCOW) 2006; 71:467-75. [PMID: 16732723 DOI: 10.1134/s0006297906050014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This review summarizes currently available information about a crucial part of erythrocyte metabolism, that is, purine nucleotide conversions and their relationships with other conversion pathways. We describe the cellular resynthesis, interconversion, and degradation of purine compounds, and also the regulatory mechanisms in the conversion pathways. We also mention purine metabolism disorders and their clinical consequences. The literature is fragmentary because studies have concentrated only on selected aspects of purine metabolism; hence the need for a synthetic approach.
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Affiliation(s)
- W Dudzinska
- Department of Biochemistry, Faculty of Natural Sciences, University of Szczecin, Szczecin, Poland.
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18
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Guinzberg R, Cortés D, Díaz-Cruz A, Riveros-Rosas H, Villalobos-Molina R, Piña E. Inosine released after hypoxia activates hepatic glucose liberation through A3 adenosine receptors. Am J Physiol Endocrinol Metab 2006; 290:E940-51. [PMID: 16352677 DOI: 10.1152/ajpendo.00173.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Inosine, an endogenous nucleoside, has recently been shown to exert potent effects on the immune, neural, and cardiovascular systems. This work addresses modulation of intermediary metabolism by inosine through adenosine receptors (ARs) in isolated rat hepatocytes. We conducted an in silico search in the GenBank and complete genomic sequence databases for additional adenosine/inosine receptors and for a feasible physiological role of inosine in homeostasis. Inosine stimulated glycogenolysis (approximately 40%, EC50 4.2 x 10(-9) M), gluconeogenesis (approximately 40%, EC50 7.8 x 10(-9) M), and ureagenesis (approximately 130%, EC50 7.0 x 10(-8) M) compared with basal values; these effects were blunted by the selective A3 AR antagonist 9-chloro-2-(2-furanyl)-5-[(phenylacetyl)amino][1,2,4]-triazolo[1,5-c]quinazoline (MRS 1220) but not by selective A1, A2A, and A2B AR antagonists. In addition, MRS 1220 antagonized inosine-induced transient increase (40%) in cytosolic Ca2+ and enhanced (90%) glycogen phosphorylase activity. Inosine-induced Ca2+ mobilization was desensitized by adenosine; in a reciprocal manner, inosine desensitized adenosine action. Inosine decreased the cAMP pool in hepatocytes when A1, A2A, and A2B AR were blocked by a mixture of selective antagonists. Inosine-promoted metabolic changes were unrelated to cAMP decrease but were Ca2+ dependent because they were absent in hepatocytes incubated in EGTA- or BAPTA-AM-supplemented Ca2+-free medium. After in silico analysis, no additional cognate adenosine/inosine receptors were found in human, mouse, and rat. In both perfused rat liver and isolated hepatocytes, hypoxia/reoxygenation produced an increase in inosine, adenosine, and glucose release; these actions were quantitatively greater in perfused rat liver than in isolated cells. Moreover, all of these effects were impaired by the antagonist MRS 1220. On the basis of results obtained, known higher extracellular inosine levels under ischemic conditions, and inosine's higher sensitivity for stimulating hepatic gluconeogenesis, it is suggested that, after tissular ischemia, inosine contributes to the maintenance of homeostasis by releasing glucose from the liver through stimulation of A3 ARs.
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Affiliation(s)
- Raquel Guinzberg
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apdo. Postal 70159, Mexico City, 04510, Mexico
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Dudzinska W, Hlynczak AJ. Purine nucleotides and their metabolites in erythrocytes of streptozotocin diabetic rats. DIABETES & METABOLISM 2005; 30:557-67. [PMID: 15671926 DOI: 10.1016/s1262-3636(07)70155-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVES In the present study it was tried to obtain a complete overview of purine nucleotide metabolism in erythrocytes of streptozotocin (STZ) induced diabetes mellitus rats. METHODS Erythrocyte levels of the main nucleotides (ATP, ADP, AMP, GTP, GDP, GMP, IMP, NAD+, NADP+), nucleosides (Ado, Guo, Ino) and the base Hyp were measured using the HPLC method. The parameters that can be deduced from their concentrations: TAN, TGN and AEC, GEC expressed by the ratio of high/low energy nucleoside phosphates were calculated. The effects of streptozotocin-induced diabetes on the concentration and metabolism of rat erythrocyte purine and pyridine nucleotides and the activity of Na+, K+-ATPase as well as Ca2+-ATPase were investigated. RESULTS Increased dephosphorylation of adenine nucleotides (found as the increased concentration of Ado and Hyp and the decrease in AEC value) and the decrease in ATP and TAN and the changes in the concentrations of NAD+ and NADP+ suggest serious purine and pyridine metabolism disruptions in diabetic erythrocytes and decrease in ATPases activity. CONCLUSION The observations suggest that purine nucleotide degradation is markedly accelerated in erythrocytes of STZ diabetic rats.
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Affiliation(s)
- W Dudzinska
- Department of Biochemistry, Faculty of Natural Sciences, University of Szczecin, 3a Felczaka, 71-412 Szczecin, Poland.
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20
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Riksen NP, Rongen GA, Boers GHJ, Blom HJ, van den Broek PHH, Smits P. Enhanced Cellular Adenosine Uptake Limits Adenosine Receptor Stimulation in Patients With Hyperhomocysteinemia. Arterioscler Thromb Vasc Biol 2005; 25:109-14. [PMID: 15539618 DOI: 10.1161/01.atv.0000150651.85907.69] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Endogenous adenosine has several cardioprotective effects. We postulate that in patients with hyperhomocysteinemia increased intracellular formation of S-adenosylhomocysteine decreases free intracellular adenosine. Subsequently, facilitated diffusion of extracellular adenosine into cells through dipyridamole-sensitive transporters is enhanced, limiting adenosine receptor stimulation. We tested this hypothesis in patients with classical homocystinuria (n=9, plasma homocysteine 93.1±24.7 μmol/L) and matched controls (n=8, homocysteine 9.1±1.0).
Methods and Results—
Infusion of adenosine (0.5, 1.5, 5.0, and 15.0 μg/min/dL forearm) into the brachial artery increased forearm blood flow, as measured with venous occlusion plethysmography, to 2.9±0.4, 4.3±0.5, 5.6±1.1, and 9.6±2.1 in the patients and to 2.8±0.6, 4.4±1.0, 9.0±1.7, and 17.0±3.1 mL/min/dL in controls (
P
<0.05). However, adenosine-induced vasodilation in the presence of dipyridamole (100 μg/min/dL) was similar in both groups (
P
=0.9). Additionally, in isolated erythrocytes, adenosine uptake was accelerated by incubation with homocysteine (half-time 6.4±0.3 versus 8.1±0.5 minutes,
P
<0.001) associated with increased intracellular formation of S-adenosylhomocysteine (
P
<0.0001).
Conclusions—
In hyperhomocysteinemia, adenosine-induced vasodilation is impaired but is restored by dipyridamole. Accelerated cellular adenosine uptake probably accounts for these observations. These impaired actions of adenosine could well contribute to the cardiovascular complications of hyperhomocysteinemia.
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Affiliation(s)
- Niels P Riksen
- Department of Pharmacology-Toxicology 233, University Medical Centre Nijmegen, Geert Grooteplein 21, 6525 EZ Nijmegen, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
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Noji T, Karasawa A, Kusaka H. Adenosine uptake inhibitors. Eur J Pharmacol 2004; 495:1-16. [PMID: 15219815 DOI: 10.1016/j.ejphar.2004.05.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Revised: 04/30/2004] [Accepted: 05/10/2004] [Indexed: 12/23/2022]
Abstract
Adenosine is a purine nucleoside and modulates a variety of physiological functions by interacting with cell-surface adenosine receptors. Under several adverse conditions, including ischemia, trauma, stress, seizures and inflammation, extracellular levels of adenosine are increased due to increased energy demands and ATP metabolism. Increased adenosine could protect against excessive cellular damage and organ dysfunction. Indeed, several protective effects of adenosine have been widely reported (e.g., amelioration of ischemic heart and brain injury, seizures and inflammation). However, the effects of adenosine itself are insufficient because extracellular adenosine is rapidly taken up into adjacent cells and subsequently metabolized. Adenosine uptake inhibitors (nucleoside transport inhibitors) could retard the disappearance of adenosine from the extracellular space by blocking adenosine uptake into cells. Therefore, it is expected that adenosine uptake inhibitors will have protective effects in various diseases, by elevating extracellular adenosine levels. Protective or ameliorating effects of adenosine uptake inhibitors in ischemic cardiac and cerebral injury, organ transplantation, seizures, thrombosis, insomnia, pain, and inflammatory diseases have been reported. Preclinical and clinical results indicate the possibility of therapeutic application of adenosine uptake inhibitors.
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Affiliation(s)
- Tohru Noji
- Pharmaceutical Research Institute, Kyowa Hakko Kogyo Co., Ltd., 1188 Shimotogari, Nagaizumi, Sunto, Shizuoka 411-8731, Japan.
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Abraham EH, Salikhova AY, Hug EB. Critical ATP parameters associated with blood and mammalian cells: Relevant measurement techniques. Drug Dev Res 2003. [DOI: 10.1002/ddr.10194] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Guieu R, Brunet P, Sampol J, Bechis G, Fenouillet E, Mege JL, Capo C, Vitte J, Ibrahim Z, Carrega L, Lerda D, Rochat H, Berland Y, Dussol B. Adenosine and hemodialysis in humans. J Investig Med 2001; 49:56-67. [PMID: 11217148 DOI: 10.2310/6650.2001.34091] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Infections and hypotension are serious complications that develop during hemodialysis (HD) treatment. Adenosine (ADO), a strong hypotensive and immunosuppressive agent, may participate in these two HD complications, because high concentrations of ADO metabolites are found in dialyzed human plasma. ADO, which is released by endothelial cells, is quickly transformed into inosine (INO) by plasmatic ADO deaminase (ADA) and mononuclear cell ADO deaminase (MCADA). In plasma, the degradation of ADO into INO and its uptake by red blood cells (RBC) are both very rapid, resulting in the short half-life of ADO in blood. METHODS Using liquid chromatography, we evaluated ADO and INO plasma concentrations before and after HD session. RESULTS Before the HD session, ADO and INO plasma concentrations were higher in hemodialyzed patients than in controls and in peritoneally dialyzed patients. At the end of the HD session, ADO plasma concentration was increased. ADO plasma concentration for the undialyzed patients was in the same range as that of the controls. Before HD, ADA activity was higher in hemodialyzed patients (559 +/- 349 IU) than in controls (219 +/- 48 IU), and the activity rose during the session (665 +/- 135 IU). ADA activity in the undialyzed patients (222 +/- 80 IU) was in the same range as that of the controls (219 +/- 48 IU). Before the HD session, the MCADA activity (247 +/- 144 IU) was lower than in controls (624 +/- 99 IU). HD did not modify ADO RBC uptake. ADO inhibited mononuclear cell proliferation and interferon-gamma production in humans. Finally, as much as 50 microM INO does not inhibit ADO uptake by RBC and does not modify ADA and MCADA activities. CONCLUSIONS These data indicate that chronic HD inhibited MCADA activity and increased ADO plasma concentration. Both high ADO plasma concentration and low MCADA activity may be involved in dialysis-induced immune system failure and thereby favor infectious diseases.
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Affiliation(s)
- R Guieu
- UMR CNRS 6560, Faculté de Médecine, Secteur Nord, Bd P. Dramard, 13015 Marseille, France.
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Dickson EW, Porcaro WA, Fenton RA, Heard SO, Reindhardt CP, Renzi FP, Przyklenk K. "Preconditioning at a distance" in the isolated rabbit heart. Acad Emerg Med 2000; 7:311-7. [PMID: 10805617 DOI: 10.1111/j.1553-2712.2000.tb02228.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Brief myocardial ischemia evokes a cardioprotective response, referred to as "ischemic preconditioning" (IP), that limits injury caused by a subsequent prolonged ischemic insult. The myocardial IP effect can be induced by ischemia of "distant" cardiac and noncardiac tissue, implicating the involvement of an as-yet-unidentified humoral trigger. If a preconditioning hormone exists, the authors hypothesize that the IP effect should be transferable, via administration of coronary effluent, from a preconditioned donor heart to a virgin non-preconditioned acceptor heart. METHODS Isolated buffer-perfused rabbit hearts were assigned to one of four treatment groups in a donor/acceptor sequence. Donor hearts underwent either three IP cycles or a matched period of uninterrupted perfusion (control donors). Coronary perfusate collected from IP and control donor hearts was reoxygenated and transfused to virgin acceptor hearts. All hearts then underwent 30 minutes of global ischemia followed by 30 minutes of reperfusion. Left ventricular developed pressure (LVDP) (the authors' index of cardioprotection) was monitored throughout the protocol by a left ventricular (LV) balloon. RESULTS In donor controls, LVDP assessed at 30 minutes post-reflow was restored to only 49 +/- 5% of baseline values. Recovery of LV function was significantly enhanced in both IP donor hearts (69 +/- 4%*) and IP acceptor hearts (70 +/- 6%*) vs donor controls (*p < 0.05), while, in acceptor controls, intermediate values of LVDP (62 +/- 7%) were obtained. CONCLUSION The IP effect can be transferred between rabbit hearts, suggesting the presence of a humoral trigger signal for distant preconditioning. Isolating this hormone may have therapeutic and diagnostic implications in the management of acute myocardial ischemia.
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Affiliation(s)
- E W Dickson
- Department of Emergency Medicine, University of Massachusetts Medical School, Worcester, USA.
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Feng JD, Yeung PK. A simple high-performance liquid chromatography assay for simultaneous measurement of adenosine, guanosine, and the oxypurine metabolites in plasma. Ther Drug Monit 2000; 22:177-83. [PMID: 10774630 DOI: 10.1097/00007691-200004000-00007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To study the effect of pharmacologic agents on the biologic fate of adenosine, a reversed-phase high-performance liquid chromatography (HPLC) assay coupled with a solid-phase extraction (SPE) method was developed for simultaneous determination of plasma adenosine, hypoxanthine, xanthine, inosine, guanosine, and uric acid. The HPLC system consisted of a reversed phase C18 column, UV detector set at 254 nm, and a mobile phase composed of 0.01 M ammonium phosphate: methanol (9.5 : 0.5) vol/vol with the final pH adjusted to 3.9. The standard curves were linear between 0.1-2 microg/mL for all the analytes (except uric acid 50-400 microg/mL), with r2 > 0.99. The absolute recoveries were >60% and accuracy >85% in almost all cases. The limit of detection was <1 ng based on absolute injection of the analytes. The intraassay variations were <10% and interassay variations <15%. The presence of a wide range of medications in plasma samples did not interfere with the assay. The assay was applied successfully to measure plasma adenosine and the oxypurine metabolites in humans and rats. It was noted that plasma concentrations of adenosine and the oxypurine metabolites can vary considerably depending on the method of blood sample collection, and that species differences are apparent.
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Affiliation(s)
- J D Feng
- Pharmacokinetics and Metabolism Laboratory, College of Pharmacy Faculty of Health Professions, Dalhousie University, Halifax, Nova Scotia, Canada
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Komarova SV, Mosharov EV, Vitvitsky VM, Ataullakhanov FI. Adenine nucleotide synthesis in human erythrocytes depends on the mode of supplementation of cell suspension with adenosine. Blood Cells Mol Dis 1999; 25:170-9. [PMID: 10575543 DOI: 10.1006/bcmd.1999.0243] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In suspensions of washed human erythrocytes, adenosine added in a single dose to concentrations of 0.1-10.0 mmol/l suspension was deaminated at rates ranging from 10 to 50 mmol/l cells h. The sum of adenosine, inosine, and hypoxanthine concentrations in the suspension, as well as the intracellular concentration of ATP, remained constant. In the presence of 25-50 mmol/l orthophosphate, addition of a single dose of adenosine into erythrocyte suspension increased the ATP concentration by up to 280% of the initial level. If the initial adenosine concentrations were greater than 5 mmol/l suspension, ATP increased independently of adenosine concentration to the level determined only by the concentration of orthophosphate. After orthophosphate was returned to its initial level, ATP in erythrocytes began to decrease. In the presence of coformycin, erythrocytes utilised adenosine at a rate of 0.2-0.3 mmol/l cells h. Their adenylate pool increased at a rate of 0.10-0.16 mmol/l cells h for several hours, but intracellular ATP increased only slightly. The energy charge of cells decreased significantly from 0.86 +/- 0.05 (control) to 0.82 +/- 0.06. Adenosine continuously pumped into erythrocyte suspensions at rates of 0.02-5.0 mmol/l cells h for several hours caused the adenylate pool of erythrocytes and intracellular ATP to increase synchronously at a rate of 0.02-0.35 mmol/l cells h. The energy charge of these erythrocytes increased significantly up to 0.91 +/- 0.03. After pumping of adenosine was stopped, the intracellular ATP and the adenylate pool began to decrease, returning sometimes to the initial level in 2-3 h.
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Affiliation(s)
- S V Komarova
- Research Center for Hematology of RAMS, Moscow, Russia
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Abstract
This study was carried out to evaluate the possible role of adenosine uptake and metabolism in mediating the inhibitory actions of this nucleoside on spontaneous mouse oocyte maturation. Uridine blocked 3H-adenosine uptake by oocyte-cumulus cell complexes (OCCs) and cumulus cell-enclosed oocytes (CEOs) by 82-85%, whereas uptake by denuded oocytes (DOs) was suppressed by 97%. Uridine had no effect on germinal vesicle breakdown (GVB) in CEOs when meiotic arrest was maintained with hypoxanthine or hypoxanthine plus adenosine but reversed the combined inhibitory action of these purines in DOs. Five of six adenosine analogs that bind to purinoceptors demonstrated meiosis-arresting activity but not in relation to their relative affinities for inhibitory or stimulatory adenosine receptors and only at high concentrations. Moreover, in DOs, uridine reversed the inhibitory effect of 2-chloroadenosine and 5'-N-ethylcarboxamidoadenosine, two receptor agonists that are poor substrates for adenosine-metabolizing enzymes. Results of experiments with adenosine kinase inhibitors showed that methylmercaptopurine riboside (MMPR) and tubercidin, but not 5'-amino-5'-deoxyadenosine, reversed meiotic arrest maintained by hypoxanthine +/- adenosine, but this required an additional inhibitory action on de novo purine synthesis. Inhibition of de novo purine synthesis alone was not sufficient because azaserine failed to reverse meiotic arrest. MMPR was a very potent meiosis-inducing agent, completely reversing meiotic arrest in CEOs and DOs in the presence of a variety of meiotic inhibitors. The adenosine deaminase inhibitor deoxycoformycin had opposite effects on oocyte maturation depending on the presence or absence of adenosine: the inhibitory action of hypoxanthine alone was bolstered, but the meiosis-arresting action of adenosine was reversed. These data therefore indicate that at low adenosine concentrations phosphorylation predominates, but at higher adenosine concentrations deaminated products contribute to the meiotic inhibition. This idea was borne out by the ability of inosine to mimic the synergistic interaction of adenosine with hypoxanthine. The action of adenosine is not due to deamination to inosine and conversion to nucleotides through the hypoxanthine salvage pathway because adenosine-mediated inhibition was not compromised in oocytes from mutant mice unable to salvage hypoxanthine.
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Affiliation(s)
- S M Downs
- Biology Department, Marquette University, Milwaukee, Wisconsin 53201-1881, USA.
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Guieu R, Dussol B, Halimi G, Bechis G, Sampieri F, Berland Y, Sampol J, Couraud F, Rochat H. Adenosine and the nervous system: pharmacological data and therapeutic perspectives. GENERAL PHARMACOLOGY 1998; 31:553-61. [PMID: 9792214 DOI: 10.1016/s0306-3623(98)00071-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
1. Adenosine acts on a family of G-protein-coupled receptors called purinoreceptors. 2. Four subtypes have been cloned and pharmacologically characterized. 3. The principal pharmacological data and structure-function relations for agonist interactions with P1 receptors are presented. 4. We conclude that the potent role of adenosine in the nervous system may be interesting for the development of drugs targeted at purines and their receptors.
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Affiliation(s)
- R Guieu
- Laboratoire de Biochimie et d'Ingéniérie des Protéines, URA CNRS 1455 Faculté de Médecine Secteur Nord, Marseille, France
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Jarvis SM, Thorn JA, Glue P. Ribavirin uptake by human erythrocytes and the involvement of nitrobenzylthioinosine-sensitive (es)-nucleoside transporters. Br J Pharmacol 1998; 123:1587-92. [PMID: 9605565 PMCID: PMC1565330 DOI: 10.1038/sj.bjp.0701775] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
1. The major toxicity associated with oral therapy with ribavirin is anaemia, which has been postulated to occur as a result of accumulation of ribavirin triphosphate interfering with erythrocyte respiration. The objective of this study was to determine the mechanism by which ribavirin enters into erythrocytes. 2. Entry into human erythrocytes was examined by measuring influx rates of [3H]-ribavirin alone and with the inhibitor nitrobenzylthioinosine (NBMPR), and by investigating the inhibitory effects of nucleoside and nucleobase permeants on ribavirin transport, by use of inhibitor oil-stop methods. Transport mechanisms were further characterized by assessment of substrates to cause countertransport of ribavirin in preloaded erythrocytes, and by measuring the effects of ribavirin on [3H]-NBMPR binding to erythrocyte membranes. 3. Human erythrocytes had a saturable influx mechanism for ribavirin (Km at 22 degrees C of 440+/-100 microM) which was inhibited by nanomolar concentrations of NBMPR (IC50 0.99+/-0.15 nM). Nucleosides also inhibited the influx of ribavirin (adenosine more effective than uridine) but the nucleobases hypoxanthine and adenine had no effect. In addition, uridine caused the countertransport of ribavirin in human erythrocytes. Entry of ribavirin into horse erythrocytes, a cell type that lacks the NBMPR-sensitive (es) nucleoside transporter, proceeded slowly and via a pathway that was resistant to NBMPR inhibition. Ribavirin was a competitive inhibitor of adenosine influx (mean Ki 0.48+/-0.14 mM) and also inhibited NBMPR binding to erythrocyte membranes (mean Ki 2.2+/-0.39 mM). 4. These data indicate that ribavirin is a transported permeant for the es nucleoside transporter of human erythrocytes. There was no evidence for ribavirin entering cells via a nucleobase transporter.
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Affiliation(s)
- S M Jarvis
- Department of Biosciences, University of Kent, Canterbury, UK
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Griffith DA, Jarvis SM. Nucleoside and nucleobase transport systems of mammalian cells. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1286:153-81. [PMID: 8982282 DOI: 10.1016/s0304-4157(96)00008-1] [Citation(s) in RCA: 377] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- D A Griffith
- Research School of Biosciences, University of Kent, Canterbary, UK
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31
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Szabados E, Christopherson RI. Rapid radioassay for metabolites of adenosine and deoxyadenosine in erythrocytes. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1995; 674:132-7. [PMID: 8749261 DOI: 10.1016/0378-4347(95)00288-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A radioassay has been developed to quantify the uptake and initial metabolism of adenosine (Ado) or deoxyadenosine (dAdo) by human erythrocytes. Cell suspension and [3H]Ado are mixed at 3-s intervals with a novel dual-syringe apparatus, and uptake and metabolism of Ado is stopped by centrifuging the cells through a dibutylphthalate layer into perchloric acid. The neutralized cell extract is analyzed by two-dimensional chromatography on poly(ethyleneimine)-cellulose plates by two procedures using combinations of solvents optimised for the separation of nucleosides and nucleobases, and for nucleotides derived from the exogenous [3H]Ado.
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Affiliation(s)
- E Szabados
- Department of Biochemistry, University of Sydney, NSW, Australia
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Wannamaker VL, Nagy LE. Equilibrative adenosine transport in rat hepatocytes after chronic ethanol feeding. Alcohol Clin Exp Res 1995; 19:735-40. [PMID: 7573801 DOI: 10.1111/j.1530-0277.1995.tb01575.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Acute treatment of cells with ethanol in vitro inhibits adenosine uptake via equilibrative nucleoside transporters. After longer periods of exposure to ethanol in culture, rechallenge with ethanol no longer inhibits adenosine uptake. Herein, we have investigated the long-term effects of ethanol consumption in vivo on equilibrative nucleoside transport. Rats were fed a liquid diet containing 35% of calories as ethanol (ethanol-fed). Control rats were pair-fed a liquid diet that isocalorically substituted maltose dextrins for ethanol. After 4 weeks of ethanol consumption, nucleoside transport was measured in isolated hepatocytes. Uptake of [3H]adenosine was lower in ethanol-fed rats compared with control. Influx of the nonmetabolizable nucleoside analog, [3H]formycin B, was also decreased after ethanol feeding. However, neither the number of nitrobenzylthioinosine (NBMPR) binding sites or inhibition of adenosine uptake by NBMPR were affected by ethanol feeding. In controls, acute treatment of isolated hepatocytes with 100 mM ethanol inhibited [3H]adenosine uptake by 30-40%. However, in ethanol-fed rats, acute challenge with ethanol did not inhibit [3H]adenosine uptake. These data demonstrate that long-term ethanol feeding decreases equilibrative nucleoside transport in hepatocytes independent of a change in the number of nucleoside transporters and renders adenosine uptake insensitive to inhibition by ethanol.
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Affiliation(s)
- V L Wannamaker
- Department of Nutritional Sciences, University of Guelph, Ontario, Canada
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Yeung PK, Mosher SJ, Li R, Farmer PS, Klassen GA, Pollak PT, McMullen M, Ferrier G. Erythrocyte adenosine transport. A rapid screening test for cardiovascular drugs. J Pharmacol Toxicol Methods 1993; 30:163-7. [PMID: 8305718 DOI: 10.1016/1056-8719(93)90041-c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
An erythrocyte (RBC) model based on whole blood was used to investigate the effect of cardiovascular drugs on the uptake of adenosine in vitro. Fresh whole blood obtained from healthy volunteers was allowed to equilibrate with various concentrations (5-1000 microM) of a tested agent. (2-3H)-Adenosine was used as a substrate, and the reaction was terminated after 2 sec of incubation at room temperature by rapid addition of a "Stopping Solution" which was a mixture of erythro-9-(2-hydroxy-3-nonyl)adenine, dipyridamole, and EDTA. The mixture was centrifuged (1760 g, 4 degrees C, 10 min), and the radioactivity of an aliquot of the supernatant was determined by a scintillation counter. The results showed that dipyridamole was the most potent agent tested (IC50 = 0.2 microM). Amongst the calcium antagonists studied, isradipine was most potent, followed by verapamil, clentiazem, diltiazem, and then nifedipine. The racemates of two metabolites of diltiazem, MX and MB, were more potent than the parent drug. The antiarrhythmic agents, amiodarone and sotalol, the two new lipid peroxidation inhibitors, U-74389F and U-78517F, and the anxiolytic agent, alprazolam, were as active as verapamil. The beta-receptor antagonist propranolol and the angiotensin converting enzyme (ACE) inhibitor, enalapril, were practically inactive. In addition, the model was stereoselective such that the S(-)-enantiomer of verapamil was considerably more potent than the R(+)-antipote, whereas d(+)-sotalol was practically inactive compared to racemic sotalol.
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Affiliation(s)
- P K Yeung
- College of Pharmacy, Dalhousie University, Halifax, Nova Scotia, Canada
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Bethlenfalvay NC, Lima JE, Banks RE. The effect of enzyme replacement on red cell adenine deoxyribonucleotides in adenosine deaminase-deficient erythrocytes of the opossum, Didelphis virginiana. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1993; 106:635-9. [PMID: 8281757 DOI: 10.1016/0305-0491(93)90141-q] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
1. Polyethyleneglycol-modified bovine adenosine deaminase was administered (10-20 U/kg/week) intramuscularly to two opossums for 15 weeks and changes in red cell adenine ribo- and deoxyribonucleotides quantitated by HPLC. 2. Only a moderate decline of erythrocyte dAXP was observed at the end of the study when compared to results of enzyme replacement seen in human adenosine deaminase deficient patients. 3. Opossum red cells salvage substantial amounts of deoxyadenosine provided in physiologic (50 nM) concentration from plasma having either low or high adenosine deaminase activity.
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Affiliation(s)
- N C Bethlenfalvay
- Department of Primary Care, Fitzsimons Army Medical Center, Aurora, CO 80045
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Abstract
[3H]Adenosine transport was characterized in cerebral cortical synaptoneurosomes prepared from postmortem human brain using an inhibitor-stop/centrifugation method. The adenosine transport inhibitors dipyridamole and dilazep completely and rapidly blocked transmembrane fluxes of [3H]adenosine. For 5-s incubations, two kinetically distinguishable processes were identified, i.e., a high-affinity adenosine transport system with Kt and Vmax values of 89 microM and 0.98 nmol/min/mg of protein, respectively, and a low-affinity adenosine transport system that did not appear to be saturable. For incubations with 1 microM [3H]adenosine as substrate, intrasynaptoneurosomal concentrations of [3H]adenosine were 0.26 microM at 5 s and 1 microM at 600 s. Metabolism of accumulated [3H]adenosine to adenine nucleotides was 15% for 5-s, 23% for 15-s, 34% for 30-s, 43% for 60-s, and 80% for 600-s incubations. The concentrations (microM) of total accumulated 3H-purines ([3H]adenosine plus metabolites) at these times were 0.3, 0.5, 1.0, 1.3 and 5.6, respectively. These results indicate that in the presence of extensive metabolism, the intrasynaptoneurosomal accumulation of 3H-purines was higher than the initial concentration of 1 microM [3H]adenosine in the reaction medium. For 5-, 15-, 30-, 60-, and 600-s incubations in the presence of the adenosine deaminase inhibitor EHNA and the adenosine kinase inhibitor 5'-iodotubercidin, metabolism of the transported [3H]adenosine was 14, 14, 16, 14, and 38%, respectively. During these times, total 3H-purine accumulation was 0.3, 0.5, 0.5, 0.7, and 1.8 microM, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J G Gu
- Department of Pharmacology and Therapeutics, University of Manitoba Faculty of Medicine, Winnipeg, Canada
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Kopff M, Zakrzewska I, Czernicki J, Klem J, Strzelczyk M. Red blood cell adenosine deaminase activity in multiple sclerosis. Clin Chim Acta 1993; 214:97-101. [PMID: 8453781 DOI: 10.1016/0009-8981(93)90306-o] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- M Kopff
- Department of Biochemistry, Military Medical Academy, Lódz, Poland
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37
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Vijayalakshmi D, Dagnino L, Belt J, Gati W, Cass C, Paterson A. L1210/B23.1 cells express equilibrative, inhibitor-sensitive nucleoside transport activity and lack two parental nucleoside transport activities. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)41877-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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38
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Yamada K, Goto A, Ishii M, Yoshioka M, Matsuoka H, Sugimoto T. Plasma adenosine concentrations are elevated in conscious spontaneously hypertensive rats. Clin Exp Pharmacol Physiol 1992; 19:563-7. [PMID: 1526061 DOI: 10.1111/j.1440-1681.1992.tb00505.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. Plasma levels of adenosine were measured in unrestrained, conscious spontaneously hypertensive rats (SHR) to examine the potential role of adenosine, a naturally occurring substance with profound cardiovascular actions, in cardiovascular regulation in these genetically hypertensive rats. 2. We employed a specific and sensitive assay for adenosine based on fluorescent determination of adenine compounds by high performance liquid chromatography. 3. Plasma adenosine concentrations were significantly higher in 13 week old SHR with hypertension than in Wistar-Kyoto rats (0.165 +/- 0.022 vs 0.096 +/- 0.008 mumol/L; P less than 0.05). 4. These observations indicate that plasma adenosine levels are increased in conscious SHR with established hypertension, and also suggest that adenosine may be at least partly involved in the pathophysiology of high blood pressure in SHR.
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Affiliation(s)
- K Yamada
- Second Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan
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Bhaumik D, Datta AK. Active site thiol(s) in Leishmania donovani adenosine kinase: comparison with hamster enzyme and evidence for the absence of regulatory adenosine binding site. Mol Biochem Parasitol 1992; 52:29-38. [PMID: 1625705 DOI: 10.1016/0166-6851(92)90033-g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Adenosine kinase (ATP, adenosine 5'-phosphotransferase, E.C. 2.7.1.20) from Leishmania donovani, unlike adenosine kinase from other known eukaryotic sources, does not elicit an inhibitory response at high concentrations of adenosine. The mechanistic basis for this unique catalytic behavior of the parasite enzyme has been probed with the help of chemical modification and enzyme inhibition kinetics experiments. The use of cysteine-directed reagents has shown that chemical integrity of cysteinyl residues is essential for the expression of functional activity of the enzyme. Thiol group titration revealed that the enzyme contains 3 cysteine residues. However, in contrast to adenosine kinase from other sources, inactivation of the parasite enzyme could be correlated with alkylation of 2 cysteinyl residues. Adenosine, but not ATP, protected 2 thiols against -SH blocker-mediated inactivation of the enzyme. The thiol groups were shown to map at positions corresponding to approximately 16, 22, and 36 kDa sites from the protein's N-terminal end. The functions of 2 thiols at the catalytic site were functional thiol groups yielded a 'protection constant' (KpAd) of 3.4 microM, while the dissociation constant (KsAD) of the enzyme-substrate complex was 2.7 microM, hence supporting involvement of the same in both processes, namely catalysis and protection. The overall results were therefore interpreted as showing that (a) the leishmanial enzyme, in contrast to adenosine kinase from other sources, contains 2 functional thiol groups at the catalytic site; and (b) the enzyme binds adenosine exclusively through the catalytic site and as a consequence is not amenable to inhibition at high adenosine concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- D Bhaumik
- Leishmania Group, Indian Institute of Chemical Biology, Calcutta, India
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40
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Gu JG, Geiger JD. Transport and metabolism of D-[3H]adenosine and L-[3H]adenosine in rat cerebral cortical synaptoneurosomes. J Neurochem 1992; 58:1699-705. [PMID: 1560227 DOI: 10.1111/j.1471-4159.1992.tb10043.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The relationship between transport and metabolism in synaptoneurosomes was examined to determine the metabolic stability of rapidly accumulated D-[3H]adenosine and L-[3H]adenosine and the degree to which metabolism of the accumulated purines affected measurements of apparent KT and Vmax values for adenosine transport. For D-[3H]adenosine, high- and low-affinity accumulation processes were present. For the high-affinity system an inverse relationship was found between transport reaction times and KT and Vmax values. For incubations of 5, 15, and 600 s, which corresponded to 24, 32, and 76% phosphorylation of accumulated D-[3H]adenosine to nucleotides, apparent KT values were 9.4, 8.4, and 4.5 microM, respectively, and Vmax values were 850, 70, and 12 pmol/min/mg of protein, respectively. Pretreatment with 10 microM erythro-9-(2-hydroxy-3-nonyl)adenine, an adenosine deaminase inhibitor, and 5'-iodotubercidin, an adenosine kinase inhibitor, decreased the phosphorylation of accumulated D-[3H]adenosine to 6% with 5-s and 9% with 15-s incubations. This resulted in significantly higher KT values: 36 microM at 5 s and 44 microM at 15 s. At 10-min incubations in the presence of these inhibitors, metabolism of accumulated D-[3H]adenosine was 32%, and apparent KT and Vmax values at this time were not significantly different from those obtained without inhibitors. For L-[3H]adenosine, apparent KT and Vmax values for 20-s incubations were 38.7 microM and 330 pmol/min/mg of protein, respectively. Metabolism (mainly phosphorylation) of accumulated L-[3H]adenosine was observed only at incubations of greater than 30 s.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J G Gu
- Department of Pharmacology and Therapeutics, University of Manitoba Faculty of Medicine, Winnipeg, Canada
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41
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Gutierrez MM, Brett CM, Ott RJ, Hui AC, Giacomini KM. Nucleoside transport in brush border membrane vesicles from human kidney. BIOCHIMICA ET BIOPHYSICA ACTA 1992; 1105:1-9. [PMID: 1567888 DOI: 10.1016/0005-2736(92)90156-g] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The goal of this study was to elucidate the mechanisms of nucleoside transport in the brush border membrane of the human kidney. [3H]Uridine was transported into brush border membrane vesicles (BBMV) from human kidney via Na(+)-independent and Na(+)-dependent processes. The Na(+)-dependent transport was saturable (Km = 4.76 +/- 0.39 microM; Vmax = 6.42 +/- 0.17 pmol/mg proteins per s) and was trans-stimulated by unlabeled uridine. Structural analogs of uridine (100 microM), 2'-deoxyuridine (2-dU) and dideoxyuridine (ddU), significantly inhibited Na(+)-uridine uptake into BBMV. Previous studies have suggested that Na(+)-nucleoside co-transport occurs via two major systems (Vijayalakshmi et al. (1988) J. Biol. Chem. 263, 19419-19423). One system (cit) is generally pyrimidine-selective; thymidine serves as a model substrate. The other system (cif) is generally purine-selective; formycin B serves as a model substrate. Uridine and adenosine are substrates of both systems. Thymidine and cytidine (100 microM), but not formycin B (100 microM) inhibited Na(+)-uridine uptake. In addition, [3H]thymidine exhibited an Na(+)-driven overshoot phenomenon whereas [3H]formycin B did not. Na(+)-thymidine uptake was inhibited by (100 microM) adenosine, uridine, guanosine, but not by formycin B and inosine. Further studies demonstrated that guanosine trans-stimulated thymidine uptake suggesting that guanosine and thymidine share a common transporter in the human renal BBMV. A different pattern was identified in BBMV from the rabbit kidney where both [3H]thymidine and [3H]formycin B as well as [3H]uridine exhibited a transient Na(+)-driven overshoot phenomenon. Collectively, these data suggest that in rabbit renal BBMV both cif and cit systems are present whereas in human renal BBMV, there appears to be a single concentrative Na(+)-nucleoside cotransport system that interacts with uridine, cytidine, thymidine, adenosine and guanosine but not with formycin B and inosine. The system is similar to the previously described cit system except that guanosine is also a substrate.
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Affiliation(s)
- M M Gutierrez
- School of Pharmacy, University of California, San Francisco 94143
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42
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Linden J, Taylor HE, Feldman MD, Woodward EB, Ayers CR, Ripley ML, Iflah S, Patel A. The precise radioimmunoassay of adenosine: minimization of sample collection artifacts and immunocrossreactivity. Anal Biochem 1992; 201:246-54. [PMID: 1632511 DOI: 10.1016/0003-2697(92)90335-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Anti-adenosine antibodies were produced in rabbits immunized with N6-carboxymethyladenosine conjugated to methyl albumin. 125I-N6-Aminobenzyladenosine was synthesized and used as a high-specific-activity, high-affinity ligand. A radioimmunoassay (RIA) was developed that can detect 6.25 nM (312.5 fmol) of underivatized adenosine and cross-reacts less than 0.02% with adenine nucleotides and guanosine and not at all with 1 mM inosine. The sensitivity of the RIA can be increased to a detection limit of 0.125 nM (6.25 fmol) by derivitizing samples with benzyl bromide to form N6-benzyladenosine. The assay was adapted to an automated RIA procedure. Assay precision was increased by: (i) inhibiting slight adenosine deaminase activity present in anti-sera; (ii) treating buffers and albumin used in the RIA with charcoal to remove contaminating adenosine; and (iii) correcting for a small but variable component of immunoreactivity not attributable to adenosine. A second antibody prepared with a 2',3'-disuccinyladenosine-albumin conjugate was also found to detect some non-adenosine-mediated immunoreactivity in plasma samples. Immunointerference in human plasma was eliminated in samples treated with ZnSO4/Ba(OH)2 or partially purified over C18 Sep Paks to remove nucleotides and assayed after sample benzylation or succinylation. Human blood was mixed with a novel "stop" solution that was optimized to inhibit adenosine formation from AMP by greater than 99% and to inhibit adenosine uptake into red cells and degradation by greater than 94%. Human plasma/stop solution was assayed by RIA and HPLC with equivalent results.
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Affiliation(s)
- J Linden
- Department of Internal Medicine (Cardiology), University of Virginia, Charlottesville 22908
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43
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Yeung PK, Mosher SJ, Macrae DA, Klassen GA. Effect of diltiazem and its metabolites on the uptake of adenosine in blood: an in-vitro investigation. J Pharm Pharmacol 1991; 43:685-9. [PMID: 1682442 DOI: 10.1111/j.2042-7158.1991.tb03458.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Using whole blood from man and rabbits, the effect of diltiazem, its metabolites, and other calcium antagonists on the uptake of adenosine has been described. The uptake and metabolism of adenosine was extremely rapid with a half-life in plasma of less than 30 s. Adenosine is rapidly and extensively metabolized to hypoxanthine. Metabolites of diltiazem, deacetyl diltiazem and deacetyl O-desmethyl diltiazem were considerably more potent than the parent drug. Diltiazem was one-tenth as active as verapamil, but more active than nifedipine or amlodipine. Dipyridamole was the most potent uptake-inhibitor tested (IC50 less than 1 microM), whereas the angiotensin converting enzyme inhibitor enalapril was virtually devoid of any inhibitory activities (IC50 greater than 1000 microM). The results obtained from both man and rabbit were similar.
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Affiliation(s)
- P K Yeung
- College of Pharmacy, Faculty of Health Professions, Dalhousie University, Halifax, Nova Scotia, Canada
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44
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Plagemann PG, Woffendin C. Mycoplasma contamination alters 2'-deoxyadenosine metabolism in deoxycoformycin-treated mouse leukemia cells. J Cell Biochem 1990; 43:161-72. [PMID: 2380261 DOI: 10.1002/jcb.240430207] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Deoxycoformycin-treated P388 and L1210 mouse leukemia cells salvage 2'-deoxyadenosine from the medium only inefficiently, because deoxyadenosine deamination is blocked and its phosphorylation is limited by feedback controls. Mycoplasma contamination at a level that had no significant effect on the growth of the cells increased the salvage of deoxyadenosine greater than 10 fold over a 90 min period of incubation at 37 degrees C, but in this case deoxyadenosine was mainly incorporated into ribonucleotides and RNA via adenine formed from deoxyadenosine by mycoplasma adenosine phosphorylase. Deoxyadenosine was an efficient substrate for this enzyme, in contrast to 2',3'-dideoxyadenosine which was not phosphorolyzed. Mycoplasma infection was confirmed by the presence of uracil phosphoribosyltransferase activity and by culture isolation. The contaminant has been identified as Mycoplasma orale. Mycoplasma infection had no effect on the deamination and phosphorylation of deoxyadenosine and adenosine, on the salvage of hypoxanthine and adenine, or on the degradation of dAMP and dATP by the cells or on their acid and alkaline phosphatase activities.
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Affiliation(s)
- P G Plagemann
- Department of Microbiology, Medical School, University of Minnesota, Minneapolis 55455
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Schrader WP, West CA. Localization of adenosine deaminase and adenosine deaminase complexing protein in rabbit heart. Implications for adenosine metabolism. Circ Res 1990; 66:754-62. [PMID: 1689616 DOI: 10.1161/01.res.66.3.754] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The distribution of adenosine deaminase and adenosine deaminase complexing protein in rabbit heart has been compared using immunohistochemical staining procedures. Sections (4-5 microns) of tissue fixed in Clarke's solution or paraformaldehyde and embedded in paraffin were stained by the peroxidase anti-peroxidase method for adenosine deaminase or complexing protein, using affinity purified antibodies. Staining for adenosine deaminase and complexing protein was observed in the central myocardium of all heart chambers. Adenosine deaminase was detected in endothelial cells of blood vessels and adjacent pericytes. The nuclei of arteries stained heavily for adenosine deaminase, whereas those of venules and small veins, although positive, stained much more lightly. The cytoplasm of blood vessel endothelial cells and smooth muscle cells of the tunica media were also weakly positive for adenosine deaminase. Endothelial cells of the endocardium and epicardium did not stain. Randomly distributed mononuclear inflammatory cells and interstitial connective tissue fibroblasts were also negative for adenosine deaminase. These results raise the possibility that endothelial cells containing adenosine deaminase could serve as a metabolic barrier preventing the free exchange of plasma and interstitial adenosine. Positive staining for complexing protein was restricted to blood vessel endothelial cells, especially cytoplasmic processes. Colocalization experiments carried out with biotinylated primary antibodies indicate that some vessels are positive for both adenosine deaminase and complexing protein. This is the first experimental evidence of possible in situ association of adenosine deaminase and complexing protein.
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Affiliation(s)
- W P Schrader
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201-0509
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Plagemann PG, Aran JM, Wohlhueter RM, Woffendin C. Mobility of nucleoside transporter of human erythrocytes differs greatly when loaded with different nucleosides. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1022:103-9. [PMID: 2302397 DOI: 10.1016/0005-2736(90)90405-d] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Time courses of transmembrane equilibration of 2-chloroadenosine, 2'-deoxyadenosine, 3'-deoxyadenosine, cytidine and 2'-deoxycytidine were measured by rapid kinetic techniques in human erythrocytes under equilibrium exchange and zero-trans conditions. The kinetic parameters for transport were computed by fitting appropriate integrated rate equations to the data pooled for seven concentrations and compared to the kinetic parameters for uridine, adenosine, thymidine and formycin B transport determined previously for human erythrocytes under comparable experimental conditions. The transport of all nucleosides conformed to the simple carrier model and was directionally symmetric. The Michaelis-Menten constants for equilibrium exchange (Kee) ranged from 22 microM for 2-chloroadenosine to about 4 mM for cytidine and the maximum velocities (Vee) differed in a similar manner, so that the first-order rate constants (Vee/Kee) were similar for all nucleosides. The kinetic parameters for 2'-deoxyadenosine transport were similar to those for adenosine transport, whereas the lack of the 3'-OH group greatly reduced the affinity of 3'-deoxyadenosine (cordycepin) for the carrier. 2', 3'-Dideoxynucleosides were transported less than 1% as efficiently as 2'- and 3'-deoxynucleosides. Thus, the 2'- and 3'-OH groups play an important role in nucleoside transport. The mobility of the carrier when loaded with pyrimidine nucleosides (reflected by Vee) was 5-10-times greater than that of the empty carrier, whereas the mobility of the adenosine-loaded or 2'-deoxyadenosine-loaded carrier was about equal to that of the empty carrier. Loading the carrier with 2-chloroadenosine or 3'-deoxyadenosine actually decreased its mobility. Thus, the differential mobility of the loaded and empty carrier differs greatly with the nucleoside substrate. The mobility of the loaded carrier as well as Kee increased with a decrease in lipid solubility of the nucleoside substrate, but the relationship was complex.
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Affiliation(s)
- P G Plagemann
- Department of Microbiology, University of Minnesota, Minneapolis 55455
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47
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Plagemann PG, Woffendin C. Use of formycin B as a general substrate for measuring facilitated nucleoside transport in mammalian cells. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 1010:7-15. [PMID: 2909251 DOI: 10.1016/0167-4889(89)90177-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Formycin B, a C-nucleoside analog of inosine, is not catabolized by human erythrocytes and mouse P388 leukemia cells and is only very inefficiently phosphorylated in these cells. This relative inertness allows the measurement of its transport into and out of the cells uncomplicated by metabolic conversions. We have measured the zero-trans and equilibrium exchange flux of formycin B in these cells by rapid kinetic techniques. The Michaelis-Menten constants and maximum velocities for formycin B transport in both types of cell were similar to those previously reported for uridine and thymidine. Nevertheless, the differential mobility of the substrate-loaded and empty carrier of human erythrocytes was less for formycin B than uridine as substrate. Formycin B influx was inhibited by other nucleosides in accordance with their affinities for the carrier, but unaffected by purines. The inhibition of formycin B influx by nitrobenzylthioinosine and dipyridamole was also identical to that observed with uridine as substrate (IC50 = 10 and 30 nM, respectively). Formycin B accumulated in both types of cell to 30-40% higher concentrations than were present in the medium. This concentrative accumulation was not due to active transport, metabolism or partitioning into membrane lipids. It seems to reflect binding of formycin B to intracellular components, but does not interfere significantly with measurements of its transport.
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Affiliation(s)
- P G Plagemann
- Department of Microbiology, Medical School, University of Minnesota, Minneapolis 55455
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49
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Abstract
1. Uptake and metabolism of adenosine were investigated from both maternal (M) and fetal (F) circulations of the isolated, dually perfused guinea-pig placenta by using a single-circulation paired-tracer [( 14C]sucrose as extracellular reference, and [3H]adenosine) dilution technique. 2. Maximal [3H]adenosine uptakes (percentage of dose) from adenosine-free perfusates were 75 +/- 1 and 87 +/- 2% (mean +/- S.E. of mean) at maternal and fetal blood-tissue interfaces respectively. Rapid backflux (percentage of influx) of tritium (labelled adenosine and/or adenosine derivatives) from the placental tissue into the ipsilateral circulation was higher at the fetal (24 +/- 2%) than at the maternal side (11 +/- 2%). 3. Tritium uptakes were reduced to 50 +/- 4 (M) and 60 +/- 6% (F) when the perfusion medium contained 100 microM-unlabelled adenosine; backflux was highly stimulated (44% M and 84% F). Neither uptake nor backflux were affected by inosine, uridine, adenine or hypoxanthine present in the perfusion medium (1 mM). 4. Tissue sequestration of tritium (5-6 min) was approximately 60% of the injected dose when perfusates were adenosine-free and 20% or less in the presence of 100 microM-adenosine. 5. Cellular uptake of [3H]adenosine at both sides of the placenta was markedly reduced by the nucleoside transport inhibitors dipyridamole (DIP, 10 microM) and nitrobenzylthioinosine (NBMPR, 5 microM). 6. Thin-layer chromatographic separation of [3H]inosine, [3H]hypoxanthine and [3H]phosphorylated derivatives in venous effluents following a bolus arterial injection of [3H]adenosine showed a greater fraction of metabolites at the fetal side (about 0.75) than at the maternal side (about 0.50). The percentage of [3H]inosine increased when perfusates contained 100 microM-adenosine and the effect was more marked in the fetal circulation. In the presence of DIP and NBMPR the fractional recovery of 3H-labelled metabolites was greatly reduced. 7. During steady-state perfusion of [3H]adenosine (100 microM) a maintained (5-60 min) tritium uptake of about 55% was observed and all the effluent activity was 3H-labelled metabolites [( 3H]adenosine was only 2.8 +/- 0.2%). Under these conditions high-performance liquid chromatography (HPLC) showed that effluents contained xanthine and urate at 16 +/- 1 and 23 +/- 2 microM respectively. 8. Transplacental transfer (6 min) of tritiated compounds (of which only 10-20% was [3H]adenosine) was often less than that of the extracellular marker [14C]sucrose in both maternal-to-fetal and fetal-to-maternal directions.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- C P Wheeler
- Department of Physiology, King's College London, University of London
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50
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Plagemann PG, Wohlhueter RM, Woffendin C. Nucleoside and nucleobase transport in animal cells. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 947:405-43. [PMID: 3048401 DOI: 10.1016/0304-4157(88)90002-0] [Citation(s) in RCA: 280] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- P G Plagemann
- Department of Microbiology, University of Minnesota, Minneapolis 55455
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