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McMichael LE, Heath H, Johnson CM, Fanter R, Alarcon N, Quintana-Diaz A, Pilolla K, Schaffner A, Jelalian E, Wing RR, Brito A, Phelan S, La Frano MR. Metabolites involved in purine degradation, insulin resistance, and fatty acid oxidation are associated with prediction of Gestational diabetes in plasma. Metabolomics 2021; 17:105. [PMID: 34837546 PMCID: PMC8741304 DOI: 10.1007/s11306-021-01857-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/20/2021] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Gestational diabetes mellitus (GDM) significantly increases maternal and fetal health risks, but factors predictive of GDM are poorly understood. OBJECTIVES Plasma metabolomics analyses were conducted in early pregnancy to identify potential metabolites associated with prediction of GDM. METHODS Sixty-eight pregnant women with overweight/obesity from a clinical trial of a lifestyle intervention were included. Participants who developed GDM (n = 34; GDM group) were matched on treatment group, age, body mass index, and ethnicity with those who did not develop GDM (n = 34; Non-GDM group). Blood draws were completed early in pregnancy (10-16 weeks). Plasma samples were analyzed by UPLC-MS using three metabolomics assays. RESULTS One hundred thirty moieties were identified. Thirteen metabolites including pyrimidine/purine derivatives involved in uric acid metabolism, carboxylic acids, fatty acylcarnitines, and sphingomyelins (SM) were different when comparing the GDM vs. the Non-GDM groups (p < 0.05). The most significant differences were elevations in the metabolites' hypoxanthine, xanthine and alpha-hydroxybutyrate (p < 0.002, adjusted p < 0.02) in GDM patients. A panel consisting of four metabolites: SM 14:0, hypoxanthine, alpha-hydroxybutyrate, and xanthine presented the highest diagnostic accuracy with an AUC = 0.833 (95% CI: 0.572686-0.893946), classifying as a "very good panel". CONCLUSION Plasma metabolites mainly involved in purine degradation, insulin resistance, and fatty acid oxidation, were altered in early pregnancy in connection with subsequent GDM development.
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Affiliation(s)
- Lauren E McMichael
- Department of Food Science and Nutrition, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Hannah Heath
- Department of Food Science and Nutrition, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Catherine M Johnson
- Department of Food Science and Nutrition, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Rob Fanter
- College of Agriculture, Food and Environmental Sciences, California Polytechnic State University, San Luis Obispo, CA, USA
- Cal Poly Metabolomics Service Center, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Noemi Alarcon
- Department of Kinesiology and Public Health, California Polytechnic State University, 1 Grand Ave, San Luis Obispo, CA, 93407, USA
- Center for Health Research, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Adilene Quintana-Diaz
- Department of Kinesiology and Public Health, California Polytechnic State University, 1 Grand Ave, San Luis Obispo, CA, 93407, USA
- Center for Health Research, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Kari Pilolla
- Department of Food Science and Nutrition, California Polytechnic State University, San Luis Obispo, CA, USA
- Center for Health Research, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Andrew Schaffner
- Center for Health Research, California Polytechnic State University, San Luis Obispo, CA, USA
- Department of Statistics, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Elissa Jelalian
- Department of Psychiatry and Human Behavior, Warren Alpert Medical School at Brown University, Providence, RI, USA
| | - Rena R Wing
- Department of Psychiatry and Human Behavior, Warren Alpert Medical School at Brown University, Providence, RI, USA
| | - Alex Brito
- Laboratory of Pharmacokinetics and Metabolomic Analysis, Institute of Translational Medicine and Biotechnology. I.M. Sechenov First, Moscow Medical University, Moscow, Russia
- World-Class Research Center Digital Biodesign and Personalized Healthcare, I.M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Suzanne Phelan
- Department of Kinesiology and Public Health, California Polytechnic State University, 1 Grand Ave, San Luis Obispo, CA, 93407, USA
- Center for Health Research, California Polytechnic State University, San Luis Obispo, CA, USA
| | - Michael R La Frano
- Department of Food Science and Nutrition, California Polytechnic State University, San Luis Obispo, CA, USA.
- Cal Poly Metabolomics Service Center, California Polytechnic State University, San Luis Obispo, CA, USA.
- Center for Health Research, California Polytechnic State University, San Luis Obispo, CA, USA.
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Ethyl Pyruvate Increases Post-Ischemic Levels of Mitochondrial Energy Metabolites: A 13C-Labeled Cerebral Microdialysis Study. Metabolites 2020; 10:metabo10070287. [PMID: 32668656 PMCID: PMC7407637 DOI: 10.3390/metabo10070287] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 01/26/2023] Open
Abstract
Mitochondrial dysfunction after transient cerebral ischemia can be monitored by cerebral microdialysis (CMD) using changes in the lactate and pyruvate concentrations and ratio. Other metabolites associated with mitochondrial (dys)function are, e.g., tricyclic acid (TCA) and purine metabolites. Ethyl pyruvate (EP) is a putative neuroprotectant, supposedly targeting mitochondrial energy metabolism, but its effect on cerebral energy metabolism has never been described using microdialysis. In this study we monitored the metabolic effects of EP in the endothelin-1 (ET-1) rat model using perfusion with 13C-succinate and analysis of endogenous and 13C-labeled metabolites in the dialysates by liquid chromatography-mass spectrometry (LC-MS). Adult Sprague Dawley rats (n = 27 of which n = 11 were included in the study) were subjected to the microdialysis experiments. Microdialysis probes were perfused with 13C-labeled succinate (1 mM), and striatal dialysates were collected at 30 min intervals before induction of the insult, during intracerebral application of ET-1, and during intravenous treatment with either EP (40 mg/kg) or placebo, which was administered immediately after the insult. The rats were subjected to transient cerebral ischemia by unilateral microinjection of ET-1 in the piriform cortex, causing vasoconstriction of the medial cerebral artery. Monitoring was continued for 5 h after reperfusion, and levels of endogenous and 13C-labeled energy metabolites before and after ischemia-reperfusion were compared in EP-treated and control groups. Infarct volumes were assessed after 24 h. In both the EP-treated and placebo groups, ET-1-induced vasoconstriction resulted in a transient depression of interstitial glucose and elevation of lactate in the ipsilateral striatum. In the reperfusion phase, the concentrations of labeled malate, isocitrate, and lactate as well as endogenous xanthine were significantly higher in the EP-group than in the placebo-group: (mean ± SEM) labeled malate: 39.5% ± 14.9, p = 0.008; labeled isocitrate: 134.8% ± 67.9, p = 0.047; labeled lactate: 61% ± 22.0, p = 0.007; and endogenous xanthine: 93.9% ± 28.3, p = 0.0009. In the placebo group, significantly elevated levels of uridine were observed (mean ± SEM) 32.5% ± 12.7, p = 0.01. Infarct volumes were not significantly different between EP-treated and placebo groups, p = 0.4679. CMD labeled with 13C-succinate enabled detection of ischemic induction and EP treatment effects in the ET-1 rat model of transient focal cerebral ischemia. EP administered as a single intravenous bolus in the reperfusion-phase after transient cerebral ischemia increased de novo synthesis of several key intermediate energy metabolites (13C-malate, 13C-isocitrate, and endogenous xanthine). In summary, mitochondria process 13C-succinate more effectively after EP treatment.
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Dudzinska W, Lubkowska A, Dolegowska B, Suska M, Janiak M. Uridine--an indicator of post-exercise uric acid concentration and blood pressure. Physiol Res 2014; 64:467-77. [PMID: 25470512 DOI: 10.33549/physiolres.932766] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Studies have shown that uridine concentration in plasma may be an indicator of uric acid production in patients with gout. It has been also postulated that uridine takes part in blood pressure regulation. Since physical exercise is an effective tool in treatment and prevention of cardio-vascular diseases that are often accompanied by hyperuricemia and hypertension, it seemed advisable to attempt to evaluate the relationship between oxypurine concentrations (Hyp, Xan and UA) and that of Urd and BP after physical exercise in healthy subjects. Sixty healthy men (17.2+/-1.71 years, BMI 23.2+/-2.31 kg m(-2), VO(2max) 54.7+/-6.48 ml kg(-1) min(-1)) took part in the study. The subjects performed a single maximal physical exercise on a bicycle ergometer. Blood for analyses was sampled three times: immediately before exercise, immediately after exercise, and in the 30th min of rest. Concentrations of uridine and hypoxanthine, xanthine and uric acid were determined in whole blood using high-performance liquid chromatography. We have shown in this study that the maximal exercise-induced increase of uridine concentration correlates with the post-exercise increase of uric acid concentration and systolic blood pressure. The results of our study show a relationship between uridine concentration in blood and uric acid concentration and blood pressure. We have been the first to demonstrate that a maximal exercise-induced increase in uridine concentration is correlated with the post-exercise and recovery-continued increase of uric acid concentration in healthy subjects. Thus, it appears that uridine may be an indicator of post-exercise hyperuricemia and blood pressure.
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Affiliation(s)
- W Dudzinska
- Department of Physiology, Faculty of Biology, University of Szczecin, Szczecin, Poland.
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Yamamoto T, Koyama H, Kurajoh M, Shoji T, Tsutsumi Z, Moriwaki Y. Biochemistry of uridine in plasma. Clin Chim Acta 2011; 412:1712-24. [PMID: 21689643 DOI: 10.1016/j.cca.2011.06.006] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 06/04/2011] [Accepted: 06/06/2011] [Indexed: 11/18/2022]
Abstract
Uridine is a pyrimidine nucleoside that plays a crucial role in synthesis of RNA, glycogen, and biomembrane. In humans, uridine is present in plasma in considerably higher quantities than other purine and pyrimidine nucleosides, thus it may be utilized for endogenous pyrimidine synthesis. Uridine has a number of biological effects on a variety of organs with or without disease, such as the reproductive organs, central and peripheral nervous systems, and liver. In addition, it is used in clinical situations as a rescue agent to protect against the adverse effects of 5-fluorouracil. Since the biological actions of uridine may be related to its plasma concentration, it is important to examine factors that have effects on that concentration. Factors associated with an increase in plasma concentration of uridine include enhanced ATP consumption, enhanced uridine diphosphate (UDP)-glucose consumption via glycogenesis, inhibited uridine uptake by cells via the nucleoside transport pathway, increased intestinal absorption, and increased 5-phosphribosyl-1-pyrophosphate and urea synthesis. In contrast, factors that decrease the plasma concentration of uridine are associated with accelerated uridine uptake by cells via the nucleoside transport pathway and decreased pyrimidine synthesis.
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Affiliation(s)
- Tetsuya Yamamoto
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
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Yamamoto T, Inokuchi T, Ka T, Yamamoto A, Takahashi S, Tsutsumi Z, Tamada D, Okuda C, Moriwaki Y. Relationship between plasma uridine and insulin resistance in patients with non-insulin-dependent diabetes mellitus. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2010; 29:504-8. [PMID: 20544544 DOI: 10.1080/15257771003740986] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE It has been demonstrated that uridine infusion induces insulin resistance in rats. Furthermore, it was recently reported that plasma uridine is correlated with homeostasis model assessment of insulin resistance (HOMA-R) in hypertensive patients. Therefore, we investigated whether plasma uridine was correlated with HOMA-R in patients with non-insulin-dependent diabetes mellitus (NIDDM). SUBJECTS AND METHODS The subjects were 23 male patients with NIDDM (average age 63 years) and 18 healthy males (average age 60 years). Blood samples were drawn after an overnight fast, plasma uridine was then measured using high-performance liquid chromatography. RESULTS The average plasma uridine concentration in patients with NIDDM was higher than that in healthy subjects (P < 0.05). Furthermore, plasma uridine values were positively correlated with HOMA-R (r = 0.48, P < 0.05), serum insulin (r = 0.46, P < 0.05), and serum C-peptide radioimmunoreactivity (CPR) (r = 0.44, P < 0.05) values, whereas they were not significantly correlated with fasting blood glucose or hemoglobin A1c values. CONCLUSION We found a positive relationship between plasma uridine value and HOMA-R, serum insulin, and CPR, suggesting that plasma uridine is a marker of insulin resistance in patients with NIDDM.
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Affiliation(s)
- Tetsuya Yamamoto
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Hyogo College of Medicine, Japan.
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Blood uridine concentration may be an indicator of the degradation of pyrimidine nucleotides during physical exercise with increasing intensity. J Physiol Biochem 2010; 66:189-96. [PMID: 20533099 DOI: 10.1007/s13105-010-0023-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 05/12/2010] [Indexed: 10/19/2022]
Abstract
During prolonged maximal exercise, oxygen deficits occur in working muscles. Progressive hypoxia results in the impairment of the oxidative resynthesis of ATP and increased degradation of purine nucleotides. Moreover, ATP consumption decreases the conversion of UDP to UTP, to use ATP as a phosphate donor, resulting in an increased concentration of UDP, which enhances pyrimidine degradation. Because the metabolism of pyrimidine nucleotides is related to the metabolism of purines, in particular with the cellular concentration of ATP, we decided to investigate the impact of a standardized exercise with increasing intensity on the concentration of uridine, inosine, hypoxanthine, and uric acid. Twenty-two healthy male subjects volunteered to participate in this study. Blood concentrations of metabolites were determined at rest, immediately after exercise, and after 30 min of recovery using high-performance liquid chromatography. We also studied the relationship between the levels of uridine and indicators of myogenic purine degradation. The results showed that exercise with increasing intensity leads to increased concentrations of inosine, hypoxanthine, uric acid, and uridine. We found positive correlations between blood uridine levels and indicators of myogenic purine degradation (hypoxanthine), suggesting that the blood uridine level is related to purine metabolism in skeletal muscles.
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Ka T, Inokuchi T, Tamada D, Suda M, Tsutsumi Z, Okuda C, Yamamoto A, Takahashi S, Moriwaki Y, Yamamoto T. Relationship between plasma uridine and urinary urea excretion. Metabolism 2010; 59:441-5. [PMID: 19846174 DOI: 10.1016/j.metabol.2009.07.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 07/13/2009] [Indexed: 11/28/2022]
Abstract
To investigate whether the concentration of uridine in plasma is related to the urinary excretion of urea, 45 healthy male subjects with normouricemia and normal blood pressure were studied after providing informed consent. Immediately after collection of 24-hour urine, blood samples were drawn after an overnight fast except for water. The contents of ingested foods during the 24-hour urine collection period were described by the subjects and analyzed by a dietician. Simple regression analysis showed that plasma uridine was correlated with the urinary excretions of urea (R = 0.41, P < .01), uric acid (R = 0.36, P < .05), and uridine (R = 0.30, P < .05), as well as uric acid clearance (R = 0.35, P < .05) and purine intake (R = 0.30, P < .05). In contrast, multiple regression analysis showed a positive relationship only between plasma uridine and urinary excretion of urea. These results suggest that an increase in de novo pyrimidine synthesis leads to an increased concentration of uridine in plasma via nitrogen catabolism in healthy subjects with normouricemia and normal blood pressure.
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Affiliation(s)
- Tuneyoshi Ka
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Hyogo 663-6801, Japan
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Tsutsumi Z, Moriwaki Y, Takahashi S, Ka T, Yamamoto T. Oxidized low-density lipoprotein autoantibodies in patients with primary gout: effect of urate-lowering therapy. Clin Chim Acta 2004; 339:117-22. [PMID: 14687901 DOI: 10.1016/j.cccn.2003.09.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Uric acid is a strong scavenger of reactive oxygen species, which are known to contribute to the development of atherosclerosis, while the incidence of atherosclerotic diseases is rather high in patients with gout. Among the established risk factors for atherosclerosis, oxidized LDL is believed to play a major role in its development and progression. Allopurinol and its active metabolite, oxypurinol, have been suggested to possess an antioxidant ability to scavenge the hydroxyl radical. Therefore, allopurinol may be beneficial in the prevention of LDL oxidation, as well as in the treatment of hyperuricemia. The objective of this work was to determine the degree of LDL oxidation in gout and the effect of allopurinol on LDL oxidation. METHODS Age-matched male patients with primary intercritical gout and healthy male adults were included in the study. The serum concentrations of oxidized LDL autoantibodies and total antioxidant status were measured using an enzyme immunoassay. RESULTS Serum concentrations of oxidized LDL autoantibodies were significantly higher in patients with gout than the control subjects (p < 0.05) and were significantly decreased after allopurinol treatment (p < 0.05), but not by benzbromarone treatment, in spite of the similar concentrations of uric acid and total antioxidant status in serum following their separate administration. CONCLUSIONS Although the exact mechanism remains unclear, increased serum concentrations of oxidized LDL may play a role in the high incidence of coronary artery disease in gout. In addition, allopurinol may be more preferable to benzbromarone for treatment of gout in light of its inhibitory action toward LDL oxidation.
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Affiliation(s)
- Zenta Tsutsumi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Hyogo College of Medicine, Mukogawa-cho 1-1, Nishinomiya, Hyogo, 663-8501, Japan
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Abstract
The literature on the pathogenesis of hyperuricemia have been limited to the discussion of metabolic syndromes associated with risk factors for atherosclerosis and hyperuricemia and the genetics of the juvenile form of hyperuricemic nephropathies. A few new mutations in the hypoxanthine-guanine phosphoribosyltransferase gene, which result in Lesch-Nyhan syndrome, have been described. In addition, some new insight has been gained in the renal handling of uric acid by the human kidney.
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Affiliation(s)
- Manisha Ghei
- Michael Reese Hospital, Department of Internal Medicine, 2929 South Ellis Avenue, Chicago, IL 60616, USA
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Takahashi S, Yamamoto T, Tsutsumi Z, Moriwaki Y, Hada T. Increased visceral fat accumulation in patients with primary gout. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 486:131-4. [PMID: 11783469 DOI: 10.1007/0-306-46843-3_26] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- S Takahashi
- Third Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan
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Schwille PO, Schmiedl A, Manoharan M, Wipplinger J. Is there a role for uric acid in an animal model of calcium phosphate nephrocalcinosis and calcium phosphate crystallization in urine of patients with idiopathic calcium urolithiasis? An orientational study. J Endourol 1999; 13:637-45. [PMID: 10608515 DOI: 10.1089/end.1999.13.637] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Uric acid (UA), a waste product of purine metabolism, may be involved in calcium phosphate crystallization and deposition. Rats, which develop nephrocalcinosis on high-fat or magnesium-deficient diets, and patients with idiopathic calcium urolithiasis have hyperproteinuria, especially of nonalbumin protein, and a shift toward elevated serum UA. In rats, an increase in UA precursors and renal UA suggests hypoxemia, which stimulates xanthine oxidase. In patients, a primary increase in renal xanthine oxidase would explain the low urine UA in the presence of an elevated serum concentration. For calcium phosphate deposition (rats) or incorporation into stones (humans) to occur, a crucial factor may be xanthine oxidase-mediated overproduction of free radical species and subsequent tissue damage. Another factor may be whether sufficient UA is synthesized to neutralize these free radicals. Allopurinol use, which inhibits xanthine oxidase and has long been favored for the treatment of idiopathic calcium urolithiasis, may not prevent stones, because it also diminishes the availability of UA. An investigation of the factors that control serum UA homeostasis may be rewarding in research into the etiology of idiopathic calcium urolithiasis.
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Affiliation(s)
- P O Schwille
- Department of Surgery, University of Erlangen, Germany
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Yamamoto T, Moriwaki Y, Takahashi S, Tsutsumi Z, Yamakita J, Higashino K. Effect of allopurinol and benzbromarone on the concentration of uridine in plasma. Metabolism 1997; 46:1473-6. [PMID: 9439546 DOI: 10.1016/s0026-0495(97)90151-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To investigate whether allopurinol and benzbromarone affect the concentration of uridine in plasma, allopurinol or benzbromarone were administered to patients with gout for 3 to 6 months. Allopurinol decreased the concentrations of uridine and uric acid in plasma and the urinary excretion of uric acid, but increased the plasma concentration and urinary excretion of oxypurines and orotidine. Benzbromarone decreased the concentration of uric acid in plasma and increased the excretion of uric acid in urine. However, it did not affect the plasma concentration of uridine or oxypurines or the urinary excretion of oxypurines or orotidine. These results suggest that orotidilytic decarboxylase was inhibited by allopurinol and oxypurinol ribonucleotides and/or that phosphoribosyl pyrophosphate (PRPP) was consumed by conversion from hypoxanthine, allopurinol, and oxypurinol to the respective ribonucleotides, resulting in a decrease in the de novo synthesis of pyrimidine leading to the decreased concentration of uridine in plasma. Furthermore, it was suggested that benzbromarone did not affect the de novo synthesis of pyrimidine or purine.
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Affiliation(s)
- T Yamamoto
- Third Department of Internal Medicine, Hyogo College of Medicine, Japan
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