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Posma RA, Bakker SJL, Nijsten MW, Touw DJ, Tsikas D. Comprehensive GC-MS Measurement of Amino Acids, Metabolites, and Malondialdehyde in Metformin-Associated Lactic Acidosis at Admission and during Renal Replacement Treatment. J Clin Med 2024; 13:3692. [PMID: 38999257 PMCID: PMC11242773 DOI: 10.3390/jcm13133692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 06/10/2024] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
Metformin is the most widely used drug in type 2 diabetes. Regular metformin use has been associated with changes in concentrations of amino acids. In the present study, we used valid stable-isotope labeled GC-MS methods to measure amino acids and metabolites, including creatinine as well as malondialdehyde (MDA), as an oxidative stress biomarker in plasma, urine, and dialysate samples in a patient at admission to the intensive care unit and during renal replacement treatment because of metformin-associated lactic acidosis (MALA, 21 mM lactate, 175 µM metformin). GC-MS revealed lower concentrations of amino acids in plasma, normal concentrations of the nitric oxide (NO) metabolites nitrite and nitrate, and normal concentrations of MDA. Renal tubular reabsorption rates were altered on admission. The patient received renal replacement therapy over 50 to 70 h of normalized plasma amino acid concentrations and their tubular reabsorption, as well as the tubular reabsorption of nitrite and nitrate. This study indicates that GC-MS is a versatile analytical tool to measure different classes of physiological inorganic and organic substances in complex biological samples in clinical settings such as MALA.
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Affiliation(s)
- Rene A Posma
- Department of Critical Care, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Stephan J L Bakker
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Maarten W Nijsten
- Department of Critical Care, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Daan J Touw
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30623 Hannover, Germany
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Tsikas D. Application of the Bland-Altman and Receiver Operating Characteristic (ROC) Approaches to Study Isotope Effects in Gas Chromatography-Mass Spectrometry Analysis of Human Plasma, Serum and Urine Samples. Molecules 2024; 29:365. [PMID: 38257277 PMCID: PMC10818406 DOI: 10.3390/molecules29020365] [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: 12/12/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
The Bland-Altman approach is one of the most widely used mathematical approaches for method comparison and analytical agreement. This work describes, for the first time, the application of Bland-Altman to study 14N/15N and 1H/2H (D) chromatographic isotope effects of endogenous analytes of the L-arginine/nitric oxide pathway in human plasma, serum and urine samples in GC-MS. The investigated analytes included arginine, asymmetric dimethylarginine, dimethylamine, nitrite, nitrate and creatinine. There was a close correlation between the percentage difference of the retention times of the isotopologs of the Bland-Altman approach and the area under the curve (AUC) values of the receiver operating characteristic (ROC) approach (r = 0.8619, p = 0.0047). The results of the study suggest that the chromatographic isotope effects in GC-MS result from differences in the interaction strengths of H/D isotopes in the derivatives with the hydrophobic stationary phase of the GC column. D atoms attenuate the interaction of the skeleton of the molecules with the lipophilic GC stationary phase. Differences in isotope effects in plasma or serum and urine in GC-MS are suggested to be due to a kind of matrix effect, and this remains to be investigated in forthcoming studies using Bland-Altman and ROC approaches.
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Affiliation(s)
- Dimitrios Tsikas
- Core Unit Proteomics, Institute of Toxicology, Hannover Medical School, 30623 Hannover, Germany
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Tsikas D. GC-MS and GC-MS/MS measurement of malondialdehyde (MDA) in clinical studies: Pre-analytical and clinical considerations. J Mass Spectrom Adv Clin Lab 2023; 30:10-24. [PMID: 37637438 PMCID: PMC10458701 DOI: 10.1016/j.jmsacl.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 08/01/2023] [Accepted: 08/03/2023] [Indexed: 08/29/2023] Open
Abstract
Malondialdehyde (MDA; 1,3-propanedial, OHC-CH2-CHO) is one of the most frequently measured biomarkers of oxidative stress in plasma and serum. L-Arginine (Arg) is the substrate of nitric oxide synthases (NOS), which convert L-arginine to nitric oxide (NO) and L-citrulline. The Arg/NO pathway comprises several members, including the endogenous NOS-activity inhibitor asymmetric dimethylarginine (ADMA) and its major metabolite dimethyl amine (DMA), and nitrite and nitrate, the major NO metabolites. Reliable measurement of MDA and members of the Arg/NO pathway in plasma, serum, urine and in other biological samples, such as saliva and cerebrospinal fluid, is highly challenging both for analytical and pre-analytical reasons. In our group, we use validated gas chromatography-mass spectrometry (GC-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) methods for the quantitative determination in clinical studies of MDA as a biomarker of oxidative stress, and various Arg/NO metabolites that describe the status of this pathway. Here, the importance of pre-analytical issues, which has emerged from the use of GC-MS and GC-MS/MS in clinico-pharmacological studies, is discussed. Paradigmatically, two studies on the long-term oral administration of L-arginine dihydrochloride to patients suffering from peripheral arterial occlusive disease (PAOD) or coronary artery disease (CAD) were considered. Pre-analytical issues that were addressed include blood sampling, plasma or serum storage, study design (notably in long-term studies), and the alternative of measuring MDA in human urine.
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Affiliation(s)
- Dimitrios Tsikas
- Hannover Medical School, Institute of Toxicology, Core Unit Proteomics, 30623 Hannover, Germany
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Tsikas D. Mass Spectrometry-Based Evaluation of the Bland-Altman Approach: Review, Discussion, and Proposal. Molecules 2023; 28:4905. [PMID: 37446566 DOI: 10.3390/molecules28134905] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
Reliable quantification in biological systems of endogenous low- and high-molecular substances, drugs and their metabolites, is of particular importance in diagnosis and therapy, and in basic and clinical research. The analytical characteristics of analytical approaches have many differences, including in core features such as accuracy, precision, specificity, and limits of detection (LOD) and quantitation (LOQ). Several different mathematic approaches were developed and used for the comparison of two analytical methods applied to the same chemical compound in the same biological sample. Generally, comparisons of results obtained by two analytical methods yields different quantitative results. Yet, which mathematical approach gives the most reliable results? Which mathematical approach is best suited to demonstrate agreement between the methods, or the superiority of an analytical method A over analytical method B? The simplest and most frequently used method of comparison is the linear regression analysis of data observed by method A (y) and the data observed by method B (x): y = α + βx. In 1986, Bland and Altman indicated that linear regression analysis, notably the use of the correlation coefficient, is inappropriate for method-comparison. Instead, Bland and Altman have suggested an alternative approach, which is generally known as the Bland-Altman approach. Originally, this method of comparison was applied in medicine, for instance, to measure blood pressure by two devices. The Bland-Altman approach was rapidly adapted in analytical chemistry and in clinical chemistry. To date, the approach suggested by Bland-Altman approach is one of the most widely used mathematical approaches for method-comparison. With about 37,000 citations, the original paper published in the journal The Lancet in 1986 is among the most frequently cited scientific papers in this area to date. Nevertheless, the Bland-Altman approach has not been really set on a quantitative basis. No criteria have been proposed thus far, in which the Bland-Altman approach can form the basis on which analytical agreement or the better analytical method can be demonstrated. In this article, the Bland-Altman approach is re-valuated from a quantitative bioanalytical perspective, and an attempt is made to propose acceptance criteria. For this purpose, different analytical methods were compared with Gold Standard analytical methods based on mass spectrometry (MS) and tandem mass spectrometry (MS/MS), i.e., GC-MS, GC-MS/MS, LC-MS and LC-MS/MS. Other chromatographic and non-chromatographic methods were also considered. The results for several different endogenous substances, including nitrate, anandamide, homoarginine, creatinine and malondialdehyde in human plasma, serum and urine are discussed. In addition to the Bland-Altman approach, linear regression analysis and the Oldham-Eksborg method-comparison approaches were used and compared. Special emphasis was given to the relation of difference and mean in the Bland-Altman approach. Currently available guidelines for method validation were also considered. Acceptance criteria for method agreement were proposed, including the slope and correlation coefficient in linear regression, and the coefficient of variation for the percentage difference in the Bland-Altman and Oldham-Eksborg approaches.
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Affiliation(s)
- Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30623 Hannover, Germany
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de Oliveira Moreira OB, Queiroz de Souza JC, Beraldo Candido JM, do Nascimento MP, Chellini PR, de Lemos LM, de Oliveira MAL. Determination of creatinine in urine and blood serum human samples by CZE-UV using on-column internal standard injection. Talanta 2023; 258:124465. [PMID: 36965416 DOI: 10.1016/j.talanta.2023.124465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 03/13/2023] [Accepted: 03/15/2023] [Indexed: 03/27/2023]
Abstract
Creatinine is a well-stablished biomarker for kidney malfunctions and for normalization parameter of urinary quantitative information. Recently, metabolic studies have been discovering other functionalities for creatinine tests in human urine and blood serum. In this work we present an enhanced capillary electrophoresis (CE) based protocol for determination of creatinine. CE is a high-throughput separation technique that have been getting attention through the last decades and might be considered to be adopted as an analytical instrumentation for clinical purposes. In the proposed method, we performed a short injection program with on-column addition of internal standard. Additionally, the method allows a simultaneous screening of non-proteinogenic amino acids that could be considered for metabolomics purposes. We design a pilot study that successfully estimated the creatinine value in 100 urine samples with (2.85 ± 1.78) mg dL-1 LOD; (8.24 ± 5.93) mg dL-1 LOQ and 82.4% accuracy. Considering that serum creatinine is also included in the clinical laboratory routines for estimated Glomerular Filtration Rate dosage, the method was complementary applied to 10 blood serum samples, which resulted in a model with (0.4 ± 0.2) mg dL-1 LOD; (2.0 ± 0.6) mg dL-1 LOQ and 83.8% of accuracy. All results were in agreement with reference values. The proposed method promotes a great analytical frequency and reproducibility with enhanced specificity compared with the ongoing protocol by Jaffe's reaction, thereby proving to be useful as an alternative for creatinine exams that might help complete a diagnosis of a series of health-related issues.
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Affiliation(s)
- Olívia Brito de Oliveira Moreira
- Grupo de Química Analítica e Quimiometria - GQAQ, Chemistry Department, Institute of Exact Sciences, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil
| | - Jéssica Cordeiro Queiroz de Souza
- Grupo de Química Analítica e Quimiometria - GQAQ, Chemistry Department, Institute of Exact Sciences, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil
| | - João Marcos Beraldo Candido
- Grupo de Química Analítica e Quimiometria - GQAQ, Chemistry Department, Institute of Exact Sciences, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil
| | - Maria Patrícia do Nascimento
- Grupo de Química Analítica e Quimiometria - GQAQ, Chemistry Department, Institute of Exact Sciences, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil
| | - Paula Rocha Chellini
- Grupo de Química Analítica e Quimiometria - GQAQ, Chemistry Department, Institute of Exact Sciences, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil; Faculdade de Farmácia, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil
| | | | - Marcone Augusto Leal de Oliveira
- Grupo de Química Analítica e Quimiometria - GQAQ, Chemistry Department, Institute of Exact Sciences, Federal University of Juiz de Fora (UFJF), 36036-900, Juiz de Fora, MG, Brazil; National Institute of Science and Technology for Bioanalytics - INCTBio, Institute of Chemistry, University of Campinas (UNICAMP), 13083-970, Campinas, SP, Brazil.
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Ram R, Kumar D, Sarkar A. A smartphone-integrated portable rotating platform for estimation of concentration level of plasma-creatinine using whole human blood. Talanta 2023; 253:123960. [PMID: 36195027 DOI: 10.1016/j.talanta.2022.123960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 09/17/2022] [Accepted: 09/20/2022] [Indexed: 12/13/2022]
Abstract
The measurement of creatinine concentration is performed to monitor the renal health. The devices available in modern clinical laboratories for measuring creatinine concentration are accurate and provide results rapidly but may be prohibitively expensive for resource-poor settings. Therefore, developing an inexpensive yet accurate device for measuring creatinine concentration is needed. Consequently, we developed a simple, affordable, and portable spinning disc for measuring plasma-creatinine concentration with 10 μL of whole human blood. 5 μL of the alkaline picrate solution is loaded into the device and rotated at 1000 rpm to transport this solution to the periphery of the microchannel. Further, 10 μL whole blood is loaded in the same channel and spun at 1300 rpm for 10 min. The creatinine in plasma reacts with alkaline picrate (Jaffe reaction), and the color of the mixture changes to yellow-orange color. The resulting color is captured with a smartphone, and creatinine concentration is estimated using an in-house developed app (CREA-SESE). The value of creatinine measured with the present device and the gold standard device are highly correlated (R2 = 0.998). The bias and standard deviation of the difference between the two measurements are 0.134 mg/dL and 0.143 mg/dL. This study demonstrates the feasibility of a simple, inexpensive, and portable rotating device for measuring creatinine concentration using 10 μL of whole human blood, which can easily be deployed to the underserved population in resource-constrained settings to monitor renal diseases.
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Affiliation(s)
- Rishi Ram
- Department of Mechanical Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India
| | - Dharmendra Kumar
- Department of Mechanical Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India
| | - Arnab Sarkar
- Department of Mechanical Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India.
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Liu WS, Lin CH, Li SY, Lin CC, Liu TY, Tan AC, Tsou HH, Chan HL, Lai YT. Perfluorooctanesulfonate Can Cause Negative Bias in Creatinine Measurement in Hemodialysis Patients Using Polysulfone Dialysis Membranes. MEMBRANES 2022; 12:778. [PMID: 36005693 PMCID: PMC9413667 DOI: 10.3390/membranes12080778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/03/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Serum creatinine is an important clinical marker for renal clearance. However, two conventional methods (Jaffe and enzymatic) are prone to interferences with organic compounds as compared to the standard method (isotope dilution-liquid chromatography-mass spectrometry) and can cause a significant negative bias. Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) are two common perfluorochemicals (PFCs) that can easily be accumulated in humans. We aimed to verify whether this bias is the result of an accumulation of PFCs. The serum creatinine values of 124 hemodialysis patients were analyzed using the three methods. We also aimed to evaluate which biochemical parameters will influence the difference between the conventional methods and the standard method. We found that a significant underestimation occurred when using the conventional methods. Albumin is an independent factor associated with negative bias, but it loses this correlation after dialysis, likely due to the removal of protein-bound uremic toxins. PFOS can cause negative bias when using the enzymatic method. Furthermore, this linear correlation is more significant in patients who used polysulfone-based dialysis membranes, possibly due to the better clearance of other uremic toxins. The serum creatinine of uremic patients can be significantly underestimated when using conventional methods. PFCs, as well the type of dialysis membrane being used, can be influencing factors.
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Affiliation(s)
- Wen-Sheng Liu
- Division of Nephrology, Department of Medicine, Taipei City Hospital Zhongxing Branch, Taipei 103, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
- College of Science and Engineering, Fu Jen Catholic University, New Taipei City 242, Taiwan
- Institute of Food Safety and Health Risk Assessment, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
- Department of Special Education, University of Taipei, Taipei 100, Taiwan
| | - Chien-Hung Lin
- School of Medicine, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
- College of Science and Engineering, Fu Jen Catholic University, New Taipei City 242, Taiwan
- Department of Pediatrics, Taipei Veterans General Hospital, Taipei 112, Taiwan
| | - Szu-Yuan Li
- School of Medicine, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
- Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan
| | - Chih-Ching Lin
- School of Medicine, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
- Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan
| | - Tsung-Yun Liu
- Institute of Food Safety and Health Risk Assessment, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Ann Charis Tan
- Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan
| | - Han-Hsing Tsou
- Institute of Food Safety and Health Risk Assessment, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
- Kim Forest Enterprise Co., Ltd., New Taipei City 221, Taiwan
| | - Hsiang-Lin Chan
- Department of Child Psychiatry, Chang Gung Memorial Hospital and University, Taoyuan 333, Taiwan
| | - Yen-Ting Lai
- College of Medicine, National Taiwan University, Taipei 100, Taiwan
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu 300, Taiwan
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Sensitivity Detection of Uric Acid and Creatinine in Human Urine Based on Nanoporous Gold. BIOSENSORS 2022; 12:bios12080588. [PMID: 36004983 PMCID: PMC9405689 DOI: 10.3390/bios12080588] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/25/2022] [Accepted: 07/27/2022] [Indexed: 11/17/2022]
Abstract
Given the significance of uric acid and creatinine in clinical diagnostic, disease prevention and treatment, a multifunctional electrochemical sensor was proposed for sensitive detection of uric acid and creatinine. The sensitive detection of uric acid was realized based on the unique electrochemical oxidation of nanoporous gold (NPG) towards uric acid, showing good linearity from 10 μM to 750 μM with a satisfactory sensitivity of 222.91 μA mM−1 cm−2 and a limit of detection (LOD) of 0.06 μM. Based on the Jaffé reaction between creatinine and picric acid, the sensitive detection of creatinine was indirectly achieved in a range from 10 to 2000 μM by determining the consumption of picric acid in the Jaffé reaction with a detection sensitivity of 195.05 μA mM−1 cm−2 and a LOD of 10 μM. For human urine detection using the proposed electrochemical sensor, the uric acid detection results were comparable to that of high-performance liquid chromatography (HPLC), with a deviation rate of less than 10.28% and the recoveries of uric acid spiked in urine samples were 89~118%. Compared with HPLC results, the deviation rate of creatinine detection in urine samples was less than 4.17% and the recoveries of creatinine spiked in urine samples ranged from 92.50% to 117.40%. The multifunctional electrochemical sensor exhibited many advantages in practical applications, including short detection time, high stability, simple operation, strong anti-interference ability, cost-effectiveness, and easy fabrication, which provided a promising alternative for urine analysis in clinical diagnosis.
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Stable-Isotope Dilution GC-MS Measurement of Metformin in Human Serum and Urine after Derivatization with Pentafluoropropionic Anhydride and Its Application in Becker Muscular Dystrophy Patients Administered with Metformin, l-Citrulline, or Their Combination. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123850. [PMID: 35744973 PMCID: PMC9229792 DOI: 10.3390/molecules27123850] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/10/2022] [Accepted: 06/10/2022] [Indexed: 12/25/2022]
Abstract
Metformin (N,N-dimethylguanylguanidine) is one of the most prescribed drugs with pleiotropic, exerted in part by not fully elucidated mechanisms of action. We developed and validated a gas chromatography-mass spectrometry (GC-MS) method for the quantitative analysis of metformin (metformin-d0) in 10-µL aliquots of human serum and urine using N,N-[dimethylo-2H6]guanylguanidine (metformin-d6) as the internal standard. The method involves evaporation of the samples to dryness, derivatization with pentafluoropropionic (PFP) anhydride in ethyl acetate (30 min, 65 °C), and extraction into toluene. The negative-ion chemical ionization GC-MS spectra of the PFP derivatives contain a single intense ion with mass-to-charge (m/z) ratios of m/z 383 for metformin-d0 and m/z 389 for metformin-d6. Our results suggest that all amine/imine groups of metformin-d0 and metformin-d6 are converted to their N,N,N-tripentafluoropropionyl derivatives, which cyclize to form a symmetric triazine derivative, of which the non-ring amine group is amidated. Quantification was performed by selected-ion monitoring (SIM) of m/z 383 and m/z 389. Upon validation, the method was applied to determine serum and urine metformin concentrations in 19 patients with Becker muscular dystrophy (BMD). Serum and urine samples were collected at baseline (Visit I), after six weeks of supplementation (Visit II) with metformin (3 × 500 mg/d; metformin group; n = 10) or l-citrulline (3 × 1500 mg/d; citrulline group; n = 9) followed by a six-week supplementation with 3 × 500 mg/d of metformin plus 3 × 1500 mg/d l-citrulline. At Visit I, the metformin concentration in the serum and urine was very low in both groups. The metformin concentrations in the serum and urine of the patients who first took metformin (MET group) were higher at Visit II and Visit III. The metformin concentration in the serum and urine samples of the patients who first took l-citrulline (CITR group) were higher at Visit III. The serum and urine concentrations of metformin were insignificantly lower in the CITR group at Visit III. The mean fractional excretion (FE) rate of metformin was 307% (Visit II) and 322% (Visit III) in the MET group, and 290% in the CITR group (Visit III). This observation suggests the accumulation of metformin in the kidney and its secretion in the urine. The GC-MS is suitable to measure reliably circulating and excretory metformin in clinical settings.
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Liang L, Xiong Y, Duan Y, Zuo W, Liu L, Ye F, Zhao S. Colorimetric detection of creatinine based on specifically modulating the peroxidase-mimicking activity of Cu-Fenton system. Biosens Bioelectron 2022; 206:114121. [PMID: 35235861 DOI: 10.1016/j.bios.2022.114121] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/29/2022] [Accepted: 02/20/2022] [Indexed: 11/25/2022]
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Specific and sensitive GC-MS analysis of hypusine, N ε-(4-amino-2-hydroxybutyl)lysine, a biomarker of hypusinated eukaryotic initiation factor eIF5A, and its application to the bi-ethnic ASOS study. Amino Acids 2022; 54:1083-1099. [PMID: 35243537 PMCID: PMC9217869 DOI: 10.1007/s00726-022-03142-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 02/15/2022] [Indexed: 12/12/2022]
Abstract
Hypusination is a unique two-step enzymatic post-translational modification of the Nε-amino group of lysine-50 of the eukaryotic initiation factor 5A (eIF5A). We developed a specific and sensitive gas chromatography–mass spectrometry (GC–MS) method for the measurement of biological hypusine (Hyp), i.e., Nε-(4-amino-2-hydroxybutyl)lysine. The method includes a two-step derivatization of Hyp: first esterification with 2 M HCl in CH3OH (60 min, 80 °C) to the methyl ester (Me) and then acylation with penta-fluoro-propionic (PFP) anhydride in ethyl acetate (30 min, 65 °C). Esterification with 2 M HCl in CD3OD was used to prepare the internal standard. The major derivatization product was identified as the un-labelled (d0Me) and the deuterium-labelled methyl esters (d3Me) derivatives: d0Me-Hyp-(PFP)5 and d3Me-Hyp-(PFP)5, respectively. Negative-ion chemical ionization generated the most intense ions with m/z 811 for d0Me-Hyp-(PFP)5 and m/z 814 for the internal standard d3Me-Hyp-(PFP)5. Selected-ion monitoring of m/z 811 and m/z 814 was used in quantitative analyses. Free Hyp was found in spot urine samples (10 µL) of two healthy subjects at 0.60 µM (0.29 µmol Hyp/mmol creatinine) in the female and 1.80 µM (0.19 µmol Hyp/mmol creatinine) in the male subject. The mean accuracy of the method in these urine samples spiked with 1–5 µM Hyp was 91–94%. The limit of detection (LOD) of the method is 1.4 fmol Hyp. The method was applied to measure the urinary excretion rates of Hyp in healthy black (n = 38, age 7.8 ± 0.7 years) and white (n = 41, age 7.7 ± 1.0 years) boys of the Arterial Stiffness in Offspring Study (ASOS). The Hyp concentrations were 3.55 [2.68–5.31] µM (range 0.54–9.84 µM) in the black boys and 3.87 [2.95–5.06] µM (range 1.0–11.7 µM) in the white boys (P = 0.64). The creatinine-corrected excretion rates were 0.25 [0.20–0.29] µmol/mmol (range 0.11–0.36 µmol/mmol) in the black boys and 0.26 [0.21–0.30] µmol/mmol (range 0.10–0.45 µmol/mmol) in the white boys (P = 0.82). These results suggest that there is no ethnic-related difference in the ASOS population in the eIF5A modification. Remarkable differences were found between black and white boys with respect to correlations of urinary Hyp with amino acids and advanced glycation end-products of Lys, Arg and Cys. Deoxyhypusine, formally the direct precursor of Hyp, seems not to be excreted in the urine by healthy subjects.
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Tsikas D. GC-MS Analysis of Biological Nitrate and Nitrite Using Pentafluorobenzyl Bromide in Aqueous Acetone: A Dual Role of Carbonate/Bicarbonate as an Enhancer and Inhibitor of Derivatization. Molecules 2021; 26:molecules26227003. [PMID: 34834091 PMCID: PMC8618377 DOI: 10.3390/molecules26227003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/16/2021] [Accepted: 11/18/2021] [Indexed: 11/16/2022] Open
Abstract
Carbon dioxide (CO2) and carbonates, which are widely distributed in nature, are constituents of inorganic and organic matter and are essential in vegetable and animal organisms. CO2 is the principal greenhouse gas in the atmosphere. In human blood, CO2/HCO3− is an important buffering system. Inorganic nitrate (ONO2−) and nitrite (ONO−) are major metabolites and abundant reservoirs of nitric oxide (NO), an endogenous multifunctional signaling molecule. Carbonic anhydrase (CA) is involved in the reabsorption of nitrite and nitrate from the primary urine. The measurement of nitrate and nitrite in biological samples is of particular importance. The derivatization of nitrate and nitrite in biological samples alongside their 15N-labeled analogs, which serve as internal standards, is a prerequisite for their analysis by gas chromatography–mass spectrometry (GC-MS). A suitable derivatization reagent is pentafluorobenzyl bromide (PFB-Br). Nitrate and nitrite are converted in aqueous acetone to PFB-ONO2 and PFB-NO2, respectively. PFB-Br is also useful for the GC-MS analysis of carbonate/bicarbonate. This is of particular importance in conditions of pharmacological CA inhibition, for instance by acetazolamide, which is accompanied by elevated concomitant excretion of nitrate, nitrite and bicarbonate, as well as by urine alkalization. We performed a series of experiments with exogenous bicarbonate (NaHCO3) added to human urine samples (range, 0 to 100 mM), as well as with endogenous bicarbonate resulting from the inhibition of CA activity in healthy subjects before and after ingestion of pharmacological acetazolamide. Our results indicate that bicarbonate enhances the derivatization of nitrate with PFB-Br. In contrast, bicarbonate decreases the derivatization of nitrite with PFB-Br. Bicarbonate is not a catalyst, but it enhances PFB-ONO2 formation and inhibits PFB-NO2 formation in a concentration-dependent manner. The effects of bicarbonate are likely to result from its reaction with PFB-Br to generate PFB-OCOOH. Nitrate reacts with concomitantly produced PFB-OCOOH to form PFB-ONO2 in addition to the direct reaction of nitrate with PFB-Br. By contrast, nitrite does not react with PFB-OCOOH to form PFB-NO2. Sample acidification by small volumes of 20 wt.% aqueous acetic acid abolishes the effects of exogenous and endogenous bicarbonate on nitrite measurement.
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Affiliation(s)
- Dimitrios Tsikas
- Core Unit Proteomics, Institute of Toxicology, Hannover Medical School, 30625 Hannover, Germany
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13
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Baskal S, Büttner P, Werner S, Besler C, Lurz P, Thiele H, Tsikas D. Profile of urinary amino acids and their post-translational modifications (PTM) including advanced glycation end-products (AGEs) of lysine, arginine and cysteine in lean and obese ZSF1 rats. Amino Acids 2021; 54:643-652. [PMID: 34250558 PMCID: PMC9117358 DOI: 10.1007/s00726-021-03042-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/29/2021] [Indexed: 01/01/2023]
Abstract
Heart failure with preserved ejection fraction (HFpEF) is associated with high mortality and has an increasing prevalence associated with the demographic change and limited therapeutic options. Underlying mechanisms are largely elusive and need to be explored to identify specific biomarkers and new targets, which mirror disease progression and intervention success. Obese ZSF1 (O-ZSF1) rats are a useful animal model, as they spontaneously develop hypertension, hyperlipidemia and glucose intolerance and finally HFpEF. The urinary profile of amino acids and their metabolites of post-translational modifications (PTM), including the advanced glycation end-products (AGEs) of lysine, arginine and cysteine, are poorly investigated in HFpEF and ZSF1 rats. The aim of the present study was to characterize the status of free amino acids and their metabolites of PTM and glycation in lean ZSF1 (L-ZSF1) and O-ZSF1 rats in urine aiming to find possible effects of glucose on the excretion of native and modified amino acids. In the urine of twelve L-ZSF1 and twelve O-ZFS1 rats collected at the age of 20 weeks, we measured the concentration of native and modified amino acids by reliable previously validated stable-isotope dilution gas chromatography-mass spectrometry (GC–MS) approaches. Serum glucose was 1.39-fold higher in the O-ZSF1 rats, while urinary creatinine concentration was 2.5-fold lower in the O-ZSF1 rats. We observed many differences in urinary amino acids excretion between L-ZSF1 and O-ZSF1 rats. The creatinine-corrected homoarginine excretion was twofold lower in the O-ZSF1 rats. We also observed distinct associations between the concentrations of serum glucose and urinary amino acids including their PTM and AGE metabolites in the L-ZSF1 and O-ZSF1 rats. Our study shows that PTM metabolites and AGEs are consistently lower in the L-ZSF1 than in the O-ZSF1 rats. Serum malondialdehyde (MDA) concentration was higher in the O-ZSF1 rats. These results suggest that hyperglycemia, hyperlipidemia and elevated oxidative stress in the O-ZSF1 rats favor PTM methylation of arginine and lysine and the glycation of lysine and cysteine. The area under the receiver operation characteristic (ROC) curve values were 0.996 for serum glucose, 0.951 for urinary creatinine, 0.939 for serum MDA, 0.885 for Nε-carboxyethyl-lysine, 0.830 for carboxyethyl-cysteine, and 0.792 for monomethyl-lysine. Non-invasive measurement of methylation and glycation products of arginine, lysine and cysteine residues in proteins in urine of L-ZSF1 and O-ZSF1 rats may be useful in studying pathophysiology and pharmacology of HFpEF.
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Affiliation(s)
- Svetlana Baskal
- Institute of Toxicology, Hannover Medical School, Core Unit Proteomics, Carl-Neuberg-Strasse 1, 30623, Hannover, Germany
| | - Petra Büttner
- Department of Cardiology, Heart Center Leipzig at University Leipzig, Leipzig, Germany
| | - Sarah Werner
- Department of Cardiology, Heart Center Leipzig at University Leipzig, Leipzig, Germany
| | - Christian Besler
- Department of Cardiology, Heart Center Leipzig at University Leipzig, Leipzig, Germany
| | - Philipp Lurz
- Department of Cardiology, Heart Center Leipzig at University Leipzig, Leipzig, Germany
| | - Holger Thiele
- Department of Cardiology, Heart Center Leipzig at University Leipzig, Leipzig, Germany
| | - Dimitrios Tsikas
- Institute of Toxicology, Hannover Medical School, Core Unit Proteomics, Carl-Neuberg-Strasse 1, 30623, Hannover, Germany.
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GC-MS Studies on Derivatization of Creatinine and Creatine by BSTFA and Their Measurement in Human Urine. Molecules 2021; 26:molecules26113206. [PMID: 34071971 PMCID: PMC8198549 DOI: 10.3390/molecules26113206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/21/2021] [Accepted: 05/22/2021] [Indexed: 12/05/2022] Open
Abstract
In consideration of its relatively constant urinary excretion rate, creatinine (2-amino-1-methyl-5H-imidazol-4-one, MW 113.1) in urine is a useful endogenous biochemical parameter to correct the urinary excretion rate of numerous endogenous and exogenous substances. Reliable measurement of creatinine by gas chromatography (GC)-based methods requires derivatization of its amine and keto groups. Creatinine exists in equilibrium with its open form creatine (methylguanidoacetic acid, MW 131.1), which has a guanidine and a carboxylic group. Trimethylsilylation and trifluoroacetylation of creatinine and creatine are the oldest reported derivatization methods for their GC-mass spectrometry (MS) analysis in human serum using flame- or electron-ionization. We performed GC-MS studies on the derivatization of creatinine (d0-creatinine), [methylo-2H3]creatinine (d3-creatinine, internal standard) and creatine (d0-creatine) with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) using standard derivatization conditions (60 min, 60 °C), yet in the absence of any base. Reaction products were characterized both in the negative-ion chemical ionization (NICI) and in the positive-ion chemical ionization (PICI) mode. Creatinine and creatine reacted with BSTFA to form several derivatives. Their early eluting N,N,O-tris(trimethylsilyl) derivatives (8.9 min) were found to be useful for the precise and accurate measurement of the sum of creatinine and creatine in human urine (10 µL, up to 20 mM) by selected-ion monitoring (SIM) of m/z 271 (d0-creatinine/d0-creatine) and m/z 274 (d3-creatinine) in the NICI mode. In the PICI mode, SIM of m/z 256, m/z 259, m/z 272 and m/z 275 was performed. BSTFA derivatization of d0-creatine from a freshly prepared solution in distilled water resulted in formation of two lMate-eluting derivatives (14.08 min, 14.72 min), presumably creatinyl-creatinine, with the creatininyl residue existing in its enol form (14.08 min) and keto form (14.72 min). Our results suggest that BSTFA derivatization does not allow specific analysis of creatine and creatinine by GC-MS. Preliminary analyses suggest that pentafluoropropionic anhydride (PFPA) is also not useful for the measurement of creatinine in the presence of creatine. Both BSTFA and PFPA facilitate the conversion of creatine to creatinine. Specific measurement of creatinine in urine is possible by using pentafluorobenzyl bromide in aqueous acetone.
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Quantitative determination of creatinine from serum of prostate cancer patients by N-doped porous carbon antimony (Sb/NPC) nanoparticles. Bioelectrochemistry 2021; 140:107815. [PMID: 33862546 DOI: 10.1016/j.bioelechem.2021.107815] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 01/24/2023]
Abstract
Creatinine is an indicator of hindrance in urination and renal insufficiency. Creatinine levels are the marker of the late stages of prostate cancer. Early and sensitive detection of creatinine can reduce deaths associated with prostate cancer. In this work, nitrogen-doped porous carbon antimony (Sb/NPC) nanoparticles are fabricated to be employed as a non-enzymatic biosensor. Sb/NPC has promising redox activity and is synthesized by a two-step reaction using low-cost precursors. Electrochemical sensing by Sb/NPC is conducted for standard creatinine solutions on a three-electrodes system. Cyclic voltammetry, amperometry, and electrochemical impedance spectroscopy are used to sense creatinine. LOD and LOQ of the Sb/NPC modified electrode are 0.74 µM and 2.4 µM, respectively. This electrode system analyzes creatinine in the serum of prostate cancer patients who have elevated PSA levels. More than 90% creatinine is recovered from a spiked serum sample of a prostate cancer patient. A direct relation is observed between PSA levels and creatinine levels in prostate cancer. The developed cyclic voltammetric setup detects trace concentrations of creatinine in serum.
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Urinary Dimethylamine (DMA) and Its Precursor Asymmetric Dimethylarginine (ADMA) in Clinical Medicine, in the Context of Nitric Oxide (NO) and Beyond. J Clin Med 2020; 9:jcm9061843. [PMID: 32545708 PMCID: PMC7356952 DOI: 10.3390/jcm9061843] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 02/08/2023] Open
Abstract
Asymmetric protein-arginine dimethylation is a major post-translational modification (PTM) catalyzed by protein-arginine methyltransferase (PRMT). Regular proteolysis releases asymmetric dimethylarginine (ADMA). Of the daily produced ADMA, about 10% are excreted unchanged in the urine. The remaining 90% are hydrolyzed by dimethylarginine dimethylaminohydrolase (DDAH) to L-citrulline and dimethylamine (DMA), which is readily excreted in the urine. The PRMT/DDAH pathway is almost the exclusive origin of urinary ADMA and the major source of urinary DMA. Dietary fish and seafood represent additional abundant sources of urinary DMA. The present article provides an overview of urinary ADMA and DMA reported thus far in epidemiological, clinical and pharmacological studies, in connection with the L-arginine/nitric oxide (NO) pathway and beyond, in neonates, children and adolescents, young and elderly subjects, males and females. Discussed diseases mainly include those relating to the renal and cardiovascular systems such as peripheral arterial occlusive disease, coronary artery disease, chronic kidney disease, rheumatoid arthritis, Becker muscular disease, Duchenne muscular disease (DMD), attention deficit hyperactivity disorder (ADHD), and type I diabetes. Under standardized conditions involving the abstinence of DMA-rich fresh and canned fish and seafood, urinary DMA and ADMA are useful as measures of whole-body asymmetric arginine-dimethylation in health and disease. The creatinine-corrected excretion rates of DMA range from 10 to 80 µmol/mmol in adults and up to 400 µmol/mmol in children and adolescents. The creatinine-corrected excretion rates of ADMA are on average 10 times lower. In general, diseases are associated with higher urinary DMA and ADMA excretion rates, and pharmacological treatment, such as with steroids and creatine (in DMD), decreases their excretion rates, which may be accompanied by a decreased urinary excretion of nitrate, the major metabolite of NO. In healthy subjects and in rheumatoid arthritis patients, the urinary excretion rate of DMA correlates positively with the excretion rate of dihydroxyphenylglycol (DHPG), the major urinary catecholamines metabolite, suggesting a potential interplay in the PRMT/DDAH/NO pathway.
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An Ethnic Comparison of Arginine Dimethylation and Cardiometabolic Factors in Healthy Black and White Youth: The ASOS and African-PREDICT Studies. J Clin Med 2020; 9:jcm9030844. [PMID: 32244968 PMCID: PMC7141317 DOI: 10.3390/jcm9030844] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/12/2020] [Accepted: 03/18/2020] [Indexed: 12/20/2022] Open
Abstract
Proteinic arginine dimethylation (PADiMe) is a major post-translational modification. Proteolysis of asymmetric and symmetric PADiMe products releases asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA), respectively, two endogenous atherogenic substances. SDMA, ADMA, and its major metabolite dimethylamine (DMA) are eliminated by the kidney. The urinary concentrations of DMA+ADMA, SDMA, and DMA+ADMA+SDMA are useful measures of the whole-body asymmetric and symmetric PADiMe, respectively. Urinary (DMA+ADMA)/SDMA is an index of the asymmetric to symmetric PADiMe balance. In two bi-ethnic studies, the ASOS (39 black boys, 41 white boys) and the African-PREDICT (292 black young men, 281 white young men) studies, we investigated whether ethnicity is a major determinant of PADiMe, and whether PADiMe is associated with blood pressure and ethnicity-dependent growth and inflammatory factors, including HDL. DMA, ADMA, and SDMA were measured in spot urine samples by gas chromatography-mass spectrometry, and their excretion was corrected for creatinine excretion. In black boys, creatinine-corrected DMA, DMA+ADMA, and DMA+ADMA+SDMA concentrations were lower by 11.7%, 9.5%, and 7.6% (all p < 0.05), respectively, compared to the white boys, and 3.4%, 2.0%, and 1.8% lower (all p < 0.05), respectively, in black compared to white men. (DMA+ADMA)/SDMA did not differ between black boys and black men, but was higher in white boys compared to white men. ADMA did not differ between black and white boys, or between black and white men. Creatinine-corrected SDMA excretion was lower in black boys compared to white boys (by 8%) and to white men (by 3.1%). None of the PADiMe indices were associated with blood pressure in either study. IGF-binding protein 3 correlated inversely with all PADiMe indices in the black men only. Our study showed that asymmetric proteinic arginine dimethylation is higher in white boys than in black boys, and that this difference disappears in adulthood. ADMA metabolism and SDMA excretion were lower in the black subjects compared to the white subjects, suggesting ethnicity-dependent hepatic and renal elimination of ADMA and SDMA in the childhood. The results of our study may have clinical relevance beyond atherosclerosis, such as in growth and inflammation, which have not been sufficiently addressed thus far.
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Huang Z, Scotland KB, Li Y, Guo J, McGeer PL, Lange D, Chen DDY. Application of multisegment injection on quantification of creatinine and standard addition analysis of urinary 5‐hydroxyindoleacetic acid simultaneously with creatinine normalization. Electrophoresis 2020; 41:183-193. [DOI: 10.1002/elps.201900456] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/07/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Zi‐Ao Huang
- Department of ChemistryUniversity of British Columbia Vancouver British Columbia Canada
| | - Kymora B. Scotland
- Department of Urologic Sciences, The Stone Centre at Vancouver General HospitalUniversity of British Columbia Vancouver British Columbia Canada
| | - Yueyang Li
- Department of ChemistryUniversity of British Columbia Vancouver British Columbia Canada
| | - Jian‐Ping Guo
- Aurin Biotech Inc. Vancouver British Columbia Canada
| | | | - Dirk Lange
- Department of Urologic Sciences, The Stone Centre at Vancouver General HospitalUniversity of British Columbia Vancouver British Columbia Canada
| | - David D. Y. Chen
- Department of ChemistryUniversity of British Columbia Vancouver British Columbia Canada
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Begou O, Drabert K, Theodoridis G, Tsikas D. GC-NICI-MS analysis of acetazolamide and other sulfonamide (R-SO 2-NH 2) drugs as pentafluorobenzyl derivatives [R-SO 2-N(PFB) 2] and quantification of pharmacological acetazolamide in human urine. J Pharm Anal 2019; 10:49-59. [PMID: 32123599 PMCID: PMC7037487 DOI: 10.1016/j.jpha.2019.11.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/19/2019] [Accepted: 11/22/2019] [Indexed: 01/06/2023] Open
Abstract
Acetazolamide (molecular mass (MM), 222) belongs to the class of sulfonamides (R-SO2-NH2) and is one of the strongest pharmacological inhibitors of carbonic anhydrase activity. Acetazolamide is excreted unchanged in the urine. Here, we report on the development, validation and biomedical application of a stable-isotope dilution GC-MS method for the reliable quantitative determination of acetazolamide in human urine. The method is based on evaporation to dryness of 50 μL urine aliquots, base-catalyzed derivatization of acetazolamide (d0-AZM) and its internal standard [acetylo-2H3]acetazolamide (d3-AZM) in 30 vol% pentafluorobenzyl (PFB) bromide in acetonitrile (60 min, 30 °C), reconstitution in toluene (200 μL) and injection of 1-μL aliquots. The negative-ion chemical ionization (NICI) mass spectra (methane) of the PFB derivatives contained several intense ions including [M]‒ at m/z 581 for d0-AZM and m/z 584 for d3-AZM, suggesting derivatization of their sulfonamide groups to form N,N-dipentafluorobenzyl derivatives (R-SO2-N(PFB)2), i.e., d0-AZM-(PFB)2 and d3-AZM-(PFB)2, respectively. Quantification was performed by selected-ion monitoring of m/z 581 and 83 for d0-AZM-(PFB)2 and m/z 584 and 86 for d3-AZM-(PFB)2. The limits of detection and quantitation of the method were determined to be 300 fmol (67 pg) and 1 μM of acetazolamide, respectively. Intra- and inter-assay precision and accuracy for acetazolamide in human urine samples in pharmacologically relevant concentration ranges were determined to be 0.3%–4.2% and 95.3%–109%, respectively. The method was applied to measure urinary acetazolamide excretion after ingestion of a 250 mg acetazolamide-containing tablet (Acemit®) by a healthy volunteer. Among other tested sulfonamide drugs, methazolamide (MM, 236) was also found to form a N,N-dipentafluorobenzyl derivative, whereas dorzolamide (MM, 324) was hardly detectable. No GC-MS peaks were obtained from the PFB bromide derivatization of hydrochlorothiazide (MM, 298), xipamide (MM, 355), indapamide and metholazone (MM, 366 each) or brinzolamide (MM, 384). We demonstrate for the first time that sulfonamide drugs can be derivatized with PFB bromide and quantitated by GC-MS. Sulfonamides with MM larger than 236 are likely to be derivatized by PFB bromide but to lack thermal stability. The sulfonamide group of acetazolamide was derivatized for the first time with pentafluorobenzyl bromide. Other sulfonamides were also derivatized for the first time with pentafluorobenzyl bromide. Pentafluorobenzyl derivatives of acetazolamide and other sulfonamides are useful for GC-MS. The validated method was used to quantify pharmacological acetazolamide in human urine.
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Affiliation(s)
- Olga Begou
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, Carl-Neuberg-Strasse 1, D-30625, Hannover, Germany
- Department of Chemistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
- BIOMIC_AUTh, Center for Interdisciplinary Research and Innovation (CIRI-AUTH), Balkan Center, 10th Km Thessaloniki-Thermi Rd, P.O. Box 8318, GR 57001, Thessaloniki, Greece
| | - Kathrin Drabert
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, Carl-Neuberg-Strasse 1, D-30625, Hannover, Germany
| | - Georgios Theodoridis
- Department of Chemistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
- BIOMIC_AUTh, Center for Interdisciplinary Research and Innovation (CIRI-AUTH), Balkan Center, 10th Km Thessaloniki-Thermi Rd, P.O. Box 8318, GR 57001, Thessaloniki, Greece
| | - Dimitrios Tsikas
- Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, Carl-Neuberg-Strasse 1, D-30625, Hannover, Germany
- Corresponding author.
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Chaneam S, Kaewyai K, Mantim T, Chaisuksant R, Wilairat P, Nacapricha D. Simultaneous and direct determination of urea and creatinine in human urine using a cost-effective flow injection system equipped with in-house contactless conductivity detector and LED colorimeter. Anal Chim Acta 2019; 1073:54-61. [DOI: 10.1016/j.aca.2019.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/17/2019] [Accepted: 05/02/2019] [Indexed: 12/15/2022]
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Zhang N, Lu M, Duan X, Liu CC, Wang H. In situ calibration of Direct Analysis in Real Time-mass spectrometry for direct quantification: Urine excretion rate index creatinine as an example. Talanta 2019; 201:134-142. [DOI: 10.1016/j.talanta.2019.03.092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 03/23/2019] [Accepted: 03/27/2019] [Indexed: 10/27/2022]
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Zhang Y, Guo H, Kim SB, Wu Y, Ostojich D, Park SH, Wang X, Weng Z, Li R, Bandodkar AJ, Sekine Y, Choi J, Xu S, Quaggin S, Ghaffari R, Rogers JA. Passive sweat collection and colorimetric analysis of biomarkers relevant to kidney disorders using a soft microfluidic system. LAB ON A CHIP 2019; 19:1545-1555. [PMID: 30912557 PMCID: PMC6830512 DOI: 10.1039/c9lc00103d] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The rich range of biomarkers in sweat and the ability to collect sweat in a non-invasive manner create interest in the use of this biofluid for assessments of health and physiological status, with potential applications that range from sports and fitness to clinical medicine. This paper introduces two important advances in recently reported classes of soft, skin-interfaced microfluidic systems for sweat capture and analysis: (1) a simple, broadly applicable means for collection of sweat that bypasses requirements for physical/mental exertion or pharmacological stimulation and (2) a set of enzymatic chemistries and colorimetric readout approaches for determining the concentrations of creatinine and urea in sweat, throughout ranges that are physiologically relevant. The results allow for routine, non-pharmacological capture of sweat for patient populations, such as infants and the elderly, that cannot be expected to sweat through exercise, and they create potential opportunities in the use of sweat for kidney disease screening/monitoring. Studies on human subjects demonstrate these essential capabilities, with quantitative comparisons to standard methods. The results expand the range of options available in microfluidic sampling and sensing of sweat for disease diagnostics and health monitoring.
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Affiliation(s)
- Yi Zhang
- Department of Biomedical, Biological, and Chemical Engineering, University of Missouri, Columbia, MO 65211, USA
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Zahoor N, Danilenko U, Vesper HW. A fully automated high-throughput liquid chromatography tandem mass spectrometry method for measuring creatinine in urine. CLINICAL MASS SPECTROMETRY (DEL MAR, CALIF.) 2019; 11:1-7. [PMID: 34414261 PMCID: PMC8372835 DOI: 10.1016/j.clinms.2018.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 11/16/2018] [Accepted: 11/19/2018] [Indexed: 10/27/2022]
Abstract
Reliable creatinine measurements are important to evaluate kidney function and for creatinine correction to reduce biological variability of other urinary analytes. A high-throughput, accurate liquid chromatography tandem mass spectrometry method for quantitation of human urinary creatinine has been developed and validated. Sample preparation was fully automated including cryovial decapping, sample ID scanning and two serial dilution steps. Quantitation was performed using a stable isotope-labeled internal standard. Multiplexed chromatographic separation of creatinine was achieved within a one-minute analysis and followed by tandem mass spectrometry in positive electrospray ionization mode. The precursor and product ions of creatinine and D3-creatinine were monitored in selected reaction monitoring mode. Method validation results showed reproducibility with within-run precision of 3.59, 3.49 and 2.84% and between-run precision of 4.01, 3.28 and 3.57% for low, medium and high quality control materials prepared from pooled donor urine, respectively. The method showed excellent accuracy with a bias of -1.94%, -0.78% and -1.07% for three levels of certified reference material. The calibration curve was linear throughout a 7.50-300 mg/dL (0.663-26.5 mmol/L) measurement range (R2 = 0.999), with the mean slope of 0.0115 (95%CI, 0.0108-0.0122) and intercept of 0.0027 (95%CI, 0.0003-0.0051). The limit of detection (LOD) of the method was 3.17 mg/dL (0.280 mmol/L). Analytical specificity was achieved by chromatographically separating creatinine from potentially interfering creatine within a one-minute run and monitoring the Quantitation Ion/Confirmation Ion (QI/CI) ratios in samples. A simple, accurate, high-throughput method was successfully developed for measuring creatinine in human urine samples.
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Affiliation(s)
- Neelam Zahoor
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy NE, MS F25, Atlanta, GA 30341, USA
| | - Uliana Danilenko
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy NE, MS F25, Atlanta, GA 30341, USA
| | - Hubert W. Vesper
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy NE, MS F25, Atlanta, GA 30341, USA
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Kalaivani GJ, Suja SK. Enzyme-less sensing of the kidney dysfunction biomarker creatinine using an inulin based bio-nanocomposite. NEW J CHEM 2019. [DOI: 10.1039/c9nj00594c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Enzyme-less electrochemical sensing of creatinine using an inulin-based bio-nanocomposite.
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Affiliation(s)
| | - S. K. Suja
- Department of Chemistry
- Lady Doak College
- Madurai
- India
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25
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Lindsay A, Costello JT. Realising the Potential of Urine and Saliva as Diagnostic Tools in Sport and Exercise Medicine. Sports Med 2018; 47:11-31. [PMID: 27294353 DOI: 10.1007/s40279-016-0558-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Accurate monitoring of homeostatic perturbations following various psychophysiological stressors is essential in sports and exercise medicine. Various biomarkers are routinely used as monitoring tools in both clinical and elite sport settings. Blood collection and muscle biopsies, both invasive in nature, are considered the gold standard for the analysis of these biomarkers in exercise science. Exploring non-invasive methods of collecting and analysing biomarkers that are capable of providing accurate information regarding exercise-induced physiological and psychological stress is of obvious practical importance. This review describes the potential benefits, and the limitations, of using saliva and urine to ascertain biomarkers capable of identifying important stressors that are routinely encountered before, during, or after intense or unaccustomed exercise, competition, over-training, and inappropriate recovery. In particular, we focus on urinary and saliva biomarkers that have previously been used to monitor muscle damage, inflammation, cardiovascular stress, oxidative stress, hydration status, and brain distress. Evidence is provided from a range of empirical studies suggesting that urine and saliva are both capable of identifying various stressors. Although additional research regarding the efficacy of using urine and/or saliva to indicate the severity of exercise-induced psychophysiological stress is required, it is likely that these non-invasive biomarkers will represent "the future" in sports and exercise medicine.
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Affiliation(s)
- Angus Lindsay
- Program in Physical Therapy and Rehabilitation Sciences, School of Medicine, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN, 55455, USA.
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK
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Jurdáková H, Górová R, Addová G, Šalingová A, Ostrovský I. FIA-MS/MS determination of creatinine in urine samples undergoing butylation. Anal Biochem 2018; 549:113-118. [PMID: 29567404 DOI: 10.1016/j.ab.2018.03.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/16/2018] [Accepted: 03/17/2018] [Indexed: 01/15/2023]
Abstract
Flow injection analysis-tandem mass spectrometry has become widely used for analysis of many biomarkers in various biological matrices. To improve the sensitivity, the compounds are often determined as their butylesters. Since the concentration of urinary excreted compounds are generally reported after normalization to creatinine, the aim of this study was to investigate the possibility of creatinine determination in urine samples which underwent butylation. The impact of derivatization on urinary creatinine determination was investigated by measuring of underivatized and derivatized samples. The 10% creatine to creatinine conversion was observed during butylation, what above 700 μmol creatine/mmol creatinine caused significant creatinine overestimation. In that case, correction for creatine conversion rate was done. QC samples at six concentration levels were examined and precision and accuracy values fulfill the European Medicine Agency validation requirements. The elaborated method was applied for determination of creatinine in 41 real human urine samples. Determined creatinine concentrations were in the range of 0.27-22.3 mmol/L, linearity was confirmed within the concentration range of 0.27-31.7 mmol/L. Obtained results highly correlated with routinely used enzymatic assay for all tested samples and proposed method provide reliable determination of creatinine in butylated urine in a single run with butylesters of other analytes of interest.
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Affiliation(s)
- Helena Jurdáková
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-2, Ilkovičova 6, 84215 Bratislava, Slovakia.
| | - Renáta Górová
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-2, Ilkovičova 6, 84215 Bratislava, Slovakia
| | - Gabriela Addová
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-2, Ilkovičova 6, 84215 Bratislava, Slovakia
| | - Anna Šalingová
- Department of Laboratory Medicine, Comenius University Children's Hospital, Limbová 1, 83340 Bratislava, Slovakia
| | - Ivan Ostrovský
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-2, Ilkovičova 6, 84215 Bratislava, Slovakia
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Results, meta-analysis and a first evaluation of U NOxR, the urinary nitrate-to-nitrite molar ratio, as a measure of nitrite reabsorption in experimental and clinical settings. Amino Acids 2018; 50:799-821. [PMID: 29728915 DOI: 10.1007/s00726-018-2573-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 04/19/2018] [Indexed: 02/07/2023]
Abstract
We recently found that renal carbonic anhydrase (CA) is involved in the reabsorption of inorganic nitrite (NO2-), an abundant reservoir of nitric oxide (NO) in tissues and cells. Impaired NO synthesis in the endothelium and decreased NO bioavailability in the circulation are considered major contributors to the development and progression of renal and cardiovascular diseases in different conditions including diabetes. Isolated human and bovine erythrocytic CAII and CAIV can convert nitrite to nitrous acid (HONO) and its anhydride N2O3 which, in the presence of thiols (RSH), are further converted to S-nitrosothiols (RSNO) and NO. Thus, CA may be responsible both for the homeostasis of nitrite and for its bioactivation to RSNO/NO. We hypothesized that enhanced excretion of nitrite in the urine may contribute to NO-related dysfunctions in the renal and cardiovascular systems, and proposed the urinary nitrate-to-nitrite molar ratio, i.e., UNOxR, as a measure of renal CA-dependent excretion of nitrite. Based on results from clinical and experimental animal studies, here, we report on a first evaluation of UNOxR. We determined UNOxR values in preterm neonates, healthy children, and adults, in children suffering from type 1 diabetes mellitus (T1DM) or Duchenne muscular dystrophy (DMD), in elderly subjects suffering from chronic rheumatic diseases, type 2 diabetes mellitus (T2DM), coronary artery disease (CAD), or peripheral arterial occlusive disease (PAOD). We also determined UNOxR values in healthy young men who ingested isosorbide dinitrate (ISDN), pentaerythrityl tetranitrate (PETN), or inorganic nitrate. In addition, we tested the utility of UNOxR in two animal models, i.e., the LEW.1AR1-iddm rat, an animal model of human T1DM, and the APOE*3-Leiden.CETP mice, a model of human dyslipidemia. Mean UNOxR values were lower in adult patients with rheumatic diseases (187) and in T2DM patients of the DALI study (74) as compared to healthy elderly adults (660) and healthy young men (1500). The intra- and inter-variabilities of UNOxR were of the order of 50% in young and elderly healthy subjects. UNOxR values were lower in black compared to white boys (314 vs. 483, P = 0.007), which is in line with reported lower NO bioavailability in black ethnicity. Mean UNOxR values were lower in DMD (424) compared to healthy (730) children, but they were higher in T1DM children (1192). ISDN (3 × 30 mg) decreased stronger UNOxR compared to PETN (3 × 80 mg) after 1 day (P = 0.046) and after 5 days (P = 0.0016) of oral administration of therapeutically equivalent doses. In healthy young men who ingested NaNO3 (0.1 mmol/kg/d), UNOxR was higher than in those who ingested the same dose of NaCl (1709 vs. 369). In LEW.1AR1-iddm rats, mean UNOxR values were lower than in healthy rats (198 vs. 308) and comparable to those in APOE*3-Leiden.CETP mice (151).
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Simultaneous GC-ECNICI-MS measurement of nitrite, nitrate and creatinine in human urine and plasma in clinical settings. J Chromatogr B Analyt Technol Biomed Life Sci 2017; 1047:207-214. [DOI: 10.1016/j.jchromb.2016.03.034] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 03/11/2016] [Accepted: 03/21/2016] [Indexed: 11/18/2022]
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Comprehensive analysis of the L-arginine/L-homoarginine/nitric oxide pathway in preterm neonates: potential roles for homoarginine and asymmetric dimethylarginine in foetal growth. Amino Acids 2017; 49:783-794. [PMID: 28161799 DOI: 10.1007/s00726-017-2382-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 01/18/2017] [Indexed: 01/21/2023]
Abstract
L-Arginine (Arg) and L-homoarginine (hArg) are precursors of nitric oxide (NO), a signalling molecule with multiple important roles in human organism. In the circulation of adults, high concentrations of asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) and low concentrations of hArg emerged as cardiovascular risk factors. Yet, the importance of the Arg/hArg/NO pathway, especially of hArg and ADMA, in preterm neonates is little understood. We comprehensively investigated the Arg/hArg/NO pathway in 106 healthy preterm infants (51 boys, 55 girls) aged between 23 + 6 and 36 + 1 gestational weeks. Babies were divided into two groups: group I consisted of 31 babies with a gestational age of 23 + 6 - 29 + 6 weeks; group II comprised 75 children with a gestational age of 30 + 0 - 36 + 1 weeks. Plasma and urine concentrations of ADMA, SDMA, hArg, Arg, dimethylamine (DMA) which is the major urinary ADMA metabolite, as well as of nitrite and nitrate, the major NO metabolites, were determined by GC-MS and GC-MS/MS methods. ADMA and hArg plasma levels, but not the hArg/ADMA molar ratio, were significantly higher in group II than in group I: 895 ± 166 nM vs. 774 ± 164 nM (P = 0.001) for ADMA and 0.56 ± 0.04 µM vs. 0.48 ± 0.08 µM (P = 0.010) for hArg. There was no statistical difference between the groups with regard to urinary ADMA (12.2 ± 4.6 vs 12.8 ± 3.6 µmol/mmol creatinine; P = 0.61) and urinary SDMA. Urinary hArg, ADMA, SDMA correlated tightly with each other. Urinary excretion of DMA was slightly higher in group I compared to group II: 282 ± 44 vs. 247 ± 35 µmol/mmol creatinine (P = 0.004). The DMA/ADMA molar ratio in urine was tendentiously higher in neonates of group I compared to group II: 27 ± 13 vs. 20 ± 5 (P = 0.065). There were no differences between the groups with respect to Arg in plasma and to nitrite and nitrate in plasma and urine. In preterm neonates, ADMA and hArg biosynthesis increases with gestational age without remarkable changes in the hArg/ADMA ratio or NO biosynthesis. Our study suggests that ADMA and hArg are involved in foetal growth.
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Hassanzadeh M, Ghaemy M. An effective approach for the laboratory measurement and detection of creatinine by magnetic molecularly imprinted polymer nanoparticles. NEW J CHEM 2017. [DOI: 10.1039/c6nj03540j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A magnetic MIP that exhibits high selectivity to capture creatinine with a binding capacity of 33.32 mg g−1was successfully synthesized.
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Affiliation(s)
- Marjan Hassanzadeh
- Polymer Chemistry Research Laboratory
- Department of Chemistry
- University of Mazandaran
- Babolsar
- Iran
| | - Mousa Ghaemy
- Polymer Chemistry Research Laboratory
- Department of Chemistry
- University of Mazandaran
- Babolsar
- Iran
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Hanff E, Eisenga MF, Beckmann B, Bakker SJL, Tsikas D. Simultaneous pentafluorobenzyl derivatization and GC-ECNICI-MS measurement of nitrite and malondialdehyde in human urine: Close positive correlation between these disparate oxidative stress biomarkers. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1043:167-175. [PMID: 27461359 DOI: 10.1016/j.jchromb.2016.07.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 07/05/2016] [Accepted: 07/15/2016] [Indexed: 01/08/2023]
Abstract
Urinary nitrite and malondialdehyde (MDA) are biomarkers of nitrosative and oxidative stress, respectively. At physiological pH values of urine and plasma, nitrite and MDA exist almost entirely in their dissociated forms, i.e., as ONO- (ONOH, pKa=3.4) and -CH(CHO)2 (CH2(CHO)2, pKa=4.5). Previously, we reported that nitrite and MDA react with pentafluorobenzyl (PFB) bromide (PFB-Br) in aqueous acetone. Here, we report on the simultaneous derivatization of nitrite and MDA and their stable-isotope labeled analogs O15NO- (4μM) and CH2(CDO)2 (1μM or 10μM) with PFB-Br (10μL) to PFBNO2, PFB15NO2, C(PFB)2(CHO)2), C(PFB)2(CDO)2 by heating acetonic urine (urine-acetone, 100:400μL) for 60min at 50°C. After acetone evaporation under a stream of nitrogen, derivatives were extracted with ethyl acetate (1mL). A 1-μL aliquot of the ethyl acetate phase dried over anhydrous Na2SO4 was injected in the splitless mode for simultaneous GC-MS analysis in the electron capture negative-ion chemical ionization mode. Quantification was performed by selected-ion monitoring (SIM) the anions [M-PFB]-m/z 46 for ONO-, m/z 47 for O15NO-, m/z 251 for -C(PFB)(CHO)2, and m/z 253 for -C(PFB)(CDO)2. The retention times were 3.18min for PFB-ONO2/PFB-O15NO2, and 7.13min for -C(PFB)(CHO)2/-C(PFB)(CDO)2. Use of CH2(CDO)2 at 1μM but not at 10μM was associated with an unknown interference with the C(PFB)2(CDO)2 peak. Endogenous MDA can be quantified using O15NO- (4μM) and CH2(CDO)2 (10μM) as the internal standards. The method is also useful for the measurement of nitrate and creatinine in addition to nitrite and MDA. Nitrite and MDA were measured by this method in urine of elderly healthy subjects (10 females, 9 males; age, 60-70 years; BMI, 25-30kg/m2). Creatinine-corrected excretion rates did not differ between males and females for MDA (62.6 [24-137] vs 80.2 [52-118]nmol/mmol, P=0.448) and for nitrite (102 [71-174] vs. 278 [110-721]nmol/mmol P=0.053). We report for the first time a close correlation (r=0.819, P<0.0001) between MDA and nitrite in human urine. This correlation is assumed to be due to involvement of myeloperoxidase which catalyzes the formation of hypochlorite (-OCl) from chloride and hydrogen peroxide. In turn, hypochlorite reacts both with nitrite and with polyunsaturated fatty acids such as arachidonic acid, with the later reaction generating MDA. The proposed mechanisms are supported by the literature but remain to be fully explored.
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Affiliation(s)
- Erik Hanff
- Centre of Pharmacology and Toxicology, Hannover Medical School, Hannover, Germany
| | - Michele F Eisenga
- Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Bibiana Beckmann
- Institute of Occupational Medicine, Hannover Medical School, Hannover, Germany
| | - Stephan J L Bakker
- Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Dimitrios Tsikas
- Centre of Pharmacology and Toxicology, Hannover Medical School, Hannover, Germany.
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Simultaneous analysis of fructose and creatinine in urine samples using GC–MS/MS and enzymatic methods. MONATSHEFTE FUR CHEMIE 2016. [DOI: 10.1007/s00706-016-1770-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Tsikas D, Rothmann S, Schneider JY, Suchy MT, Trettin A, Modun D, Stuke N, Maassen N, Frölich JC. Development, validation and biomedical applications of stable-isotope dilution GC–MS and GC–MS/MS techniques for circulating malondialdehyde (MDA) after pentafluorobenzyl bromide derivatization: MDA as a biomarker of oxidative stress and its relation to 15( S )-8- iso -prostaglandin F 2α and nitric oxide ( NO). J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1019:95-111. [DOI: 10.1016/j.jchromb.2015.10.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/15/2015] [Accepted: 10/10/2015] [Indexed: 12/22/2022]
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Affiliation(s)
- Jarinya SITTIWONG
- Department of Chemistry, Faculty of Science, Chulalongkorn University
| | - Fuangfa UNOB
- Department of Chemistry, Faculty of Science, Chulalongkorn University
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35
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Fast vaporization solid phase microextraction and ion mobility spectrometry: A new approach for determination of creatinine in biological fluids. Talanta 2015; 144:474-9. [DOI: 10.1016/j.talanta.2015.06.046] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 06/14/2015] [Accepted: 06/17/2015] [Indexed: 12/21/2022]
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36
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Effects of chronic oral l-arginine administration on the l-arginine/NO pathway in patients with peripheral arterial occlusive disease or coronary artery disease: l-Arginine prevents renal loss of nitrite, the major NO reservoir. Amino Acids 2015; 47:1961-74. [DOI: 10.1007/s00726-015-2031-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 06/13/2015] [Indexed: 12/20/2022]
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37
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The l-arginine/NO pathway, homoarginine, and nitrite-dependent renal carbonic anhydrase activity in young people with type 1 diabetes mellitus. Amino Acids 2015; 47:1865-74. [DOI: 10.1007/s00726-015-2027-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/10/2015] [Indexed: 02/05/2023]
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38
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The l-arginine/NO pathway and homoarginine are altered in Duchenne muscular dystrophy and improved by glucocorticoids. Amino Acids 2015; 47:1853-63. [DOI: 10.1007/s00726-015-2018-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/27/2015] [Indexed: 12/21/2022]
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Biosynthesis of homoarginine (hArg) and asymmetric dimethylarginine (ADMA) from acutely and chronically administered free L-arginine in humans. Amino Acids 2015; 47:1893-908. [PMID: 26031828 DOI: 10.1007/s00726-015-2012-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 05/18/2015] [Indexed: 12/17/2022]
Abstract
Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) synthesis, whereas L-arginine (Arg) and L-homoarginine (hArg) serve as substrates for NO synthesis. ADMA and other methylated arginines are generally believed to exclusively derive from guanidine (N (G))-methylated arginine residues in proteins by protein arginine methyltransferases (PRMTs) that use S-adenosylmethionine (SAM) as the methyl donor. L-Lysine is known for decades as a precursor for hArg, but only recent studies indicate that arginine:glycine amidinotransferase (AGAT) is responsible for the synthesis of hArg. AGAT catalyzes the formation of guanidinoacetate (GAA) that is methylated to creatine by guanidinoacetate methyltransferase (GAMT) which also uses SAM. The aim of the present study was to learn more about the mechanisms of ADMA and hArg formation in humans. Especially, we hypothesized that ADMA is produced by N (G)-methylation of free Arg in addition to the known PRMTs-involving mechanism. In knockout mouse models of AGAT- and GAMT-deficiency, we investigated the contribution of these enzymes to hArg synthesis. Arg infusion (0.5 g/kg, 30 min) in children (n = 11) and ingestion of high-fat protein meals by overweight men (n = 10) were used to study acute effects on ADMA and hArg synthesis. Daily Arg ingestion (10 g) or placebo for 3 or 6 months by patients suffering from peripheral arterial occlusive disease (PAOD, n = 20) or coronary artery disease (CAD, n = 30) was used to study chronic effects of Arg on ADMA synthesis. Mass spectrometric methods were used to measure all biochemical parameters in plasma and urine samples. In mice, AGAT but not GAMT was found to contribute to plasma hArg, while ADMA synthesis was independent of AGAT and GAMT. Arg infusion acutely increased plasma Arg, hArg and ADMA concentrations, but decreased the plasma hArg/ADMA ratio. High-fat protein meals acutely increased plasma Arg, hArg, ADMA concentrations, as well as the plasma hArg/ADMA ratio. In the PAOD and CAD studies, plasma Arg concentration increased in the verum compared to the placebo groups. Plasma ADMA concentration increased only in the PAOD patients who received Arg. Our study suggests that in humans a minor fraction of free Arg is rapidly metabolized to ADMA and hArg. In mice, GAMT and N (G)-methyltransferases contribute to ADMA and hArg synthesis from Arg, whereas AGAT is involved in the synthesis of hArg but not of ADMA. The underlying biochemical mechanisms remain still elusive.
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Yaroshenko IS, Kartsova LA. Determination of markers of the urinary stone disease. JOURNAL OF ANALYTICAL CHEMISTRY 2015. [DOI: 10.1134/s1061934815030223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Li M, Du Y, Zhao F, Zeng J, Mohan C, Shih WC. Reagent- and separation-free measurements of urine creatinine concentration using stamping surface enhanced Raman scattering (S-SERS). BIOMEDICAL OPTICS EXPRESS 2015; 6:849-58. [PMID: 25798309 PMCID: PMC4361439 DOI: 10.1364/boe.6.000849] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 01/26/2015] [Accepted: 02/10/2015] [Indexed: 05/21/2023]
Abstract
We report a novel reagent- and separation-free method for urine creatinine concentration measurement using stamping surface enhanced Raman scattering (S-SERS) technique with nanoporous gold disk (NPGD) plasmonic substrates, a label-free, multiplexed molecular sensing and imaging technique recently developed by us. The performance of this new technology is evaluated by the detection and quantification of creatinine spiked in three different liquids: creatinine in water, mixture of creatinine and urea in water, and creatinine in artificial urine within physiologically relevant concentration ranges. Moreover, the potential application of our method is demonstrated by creatinine concentration measurements in urine samples collected from a mouse model of nephritis. The limit of detection of creatinine was 13.2 nM (0.15 µg/dl) and 0.68 mg/dl in water and urine, respectively. Our method would provide an alternative tool for rapid, cost-effective, and reliable urine analysis for non-invasive diagnosis and monitoring of renal function.
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Affiliation(s)
- Ming Li
- Department of Electrical & Computer Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
| | - Yong Du
- Department of Biomedical Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
| | - Fusheng Zhao
- Department of Electrical & Computer Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
| | - Jianbo Zeng
- Department of Electrical & Computer Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
| | - Chandra Mohan
- Department of Biomedical Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
| | - Wei-Chuan Shih
- Department of Electrical & Computer Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
- Department of Biomedical Engineering, University of Houston, 4800 Calhoun Rd., Houston, Texas 77024,
USA
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Fraselle S, De Cremer K, Coucke W, Glorieux G, Vanmassenhove J, Schepers E, Neirynck N, Van Overmeire I, Van Loco J, Van Biesen W, Vanholder R. Development and validation of an ultra-high performance liquid chromatography-tandem mass spectrometry method to measure creatinine in human urine. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 988:88-97. [PMID: 25756209 DOI: 10.1016/j.jchromb.2015.02.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 02/18/2015] [Accepted: 02/20/2015] [Indexed: 11/19/2022]
Abstract
Despite decades of creatinine measurement in biological fluids using a large variety of analytical methods, an accurate determination of this compound remains challenging. Especially with the novel trend to assess biomarkers on large sample sets preserved in biobanks, a simple and fast method that could cope with both a high sample throughput and a low volume of sample is still of interest. In answer to these challenges, a fast and accurate ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to measure creatinine in small volumes of human urine. In this method, urine samples are simply diluted with a basic mobile phase and injected directly under positive electrospray ionization (ESI) conditions, without further purification steps. The combination of an important diluting factor (10(4) times) due to the use of a very sensitive triple quadrupole mass spectrometer (XEVO TQ) and the addition of creatinine-d3 as internal standard completely eliminates matrix effects coming from the urine. The method was validated in-house in 2012 according to the EMA guideline on bioanalytical method validation using Certified Reference samples from the German External Quality Assessment Scheme (G-Equas) proficiency test. All obtained results for accuracy and recovery are within the authorized tolerance ranges defined by G-Equas. The method is linear between 0 and 5 g/L, with LOD and LOQ of 5 × 10(-3) g/L and 10(-2) g/L, respectively. The repeatability (CV(r) = 1.03-2.07%) and intra-laboratory reproducibility (CV(RW) = 1.97-2.40%) satisfy the EMA 2012 guideline. The validated method was firstly applied to perform the German G-Equas proficiency test rounds 51 and 53, in 2013 and 2014, respectively. The obtained results were again all within the accepted tolerance ranges and very close to the reference values defined by the organizers of the proficiency test scheme, demonstrating an excellent accuracy of the developed method. The method was finally applied to measure the creatinine concentration in 210 urine samples, coming from 190 patients with a chronic kidney disease (CKD) and 20 healthy subjects. The obtained creatinine concentrations (ranging from 0.12 g/L up to 3.84 g/L) were compared, by means of a Passing Bablok regression, with the creatinine contents obtained for the same samples measured using a traditional compensated Jaffé method. The UHPLC-MS/MS method described in this paper can be used to normalize the concentration of biomarkers in urine for the extent of dilution.
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Affiliation(s)
- S Fraselle
- Scientific Institute of Public Health, Department of Food, Medicines and Consumer Safety, Brussels, Belgium.
| | - K De Cremer
- Scientific Institute of Public Health, Department of Food, Medicines and Consumer Safety, Brussels, Belgium
| | - W Coucke
- Scientific Institute of Public Health, Quality of Medical Laboratories, Brussels, Belgium
| | - G Glorieux
- Ghent University Hospital, Renal Division, Ghent, Belgium
| | | | - E Schepers
- Ghent University Hospital, Renal Division, Ghent, Belgium
| | - N Neirynck
- Ghent University Hospital, Renal Division, Ghent, Belgium
| | - I Van Overmeire
- Scientific Institute of Public Health, Department of Food, Medicines and Consumer Safety, Brussels, Belgium
| | - J Van Loco
- Scientific Institute of Public Health, Department of Food, Medicines and Consumer Safety, Brussels, Belgium
| | - W Van Biesen
- Ghent University Hospital, Renal Division, Ghent, Belgium
| | - R Vanholder
- Ghent University Hospital, Renal Division, Ghent, Belgium
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A clinical biomarker assay for the quantification of d3-creatinine and creatinine using LC-MS/MS. Bioanalysis 2014; 6:745-59. [PMID: 24702109 DOI: 10.4155/bio.13.323] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Current methods to measure skeletal muscle mass are not practical in a clinical setting. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods that measure the amount of urinary d3-creatinine enrichment after a single tracer dose of d3-creatine was developed. RESULTS The biomarkers d3-creatinine and creatinine were detected in human urine using LC-MS/MS. In this assay a surrogate analyte, d3-creatinine, was used to quantify endogenous creatinine. However, since endogenous concentrations of creatinine were orders of magnitude higher than d3-creatinine, the peak area of a less intense isotope of creatinine was acquired. A response factor is used to correct for using a less intense isotope multiple reaction monitoring transition. CONCLUSION Novel LC-MS/MS assays were developed that quantify the biomarkers d3-creatinine, creatinine and d3-creatine in urine. This method allows the estimation of total body creatine pool size and subsequent calculation of muscle mass. This assay was originally validated as fit-for-purpose and was followed by full validation.
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Tsikas D, Niemann J, Flentje M, Schwarz A, Tossios P. N-Acetylcysteine (NAC) inhibits renal nitrite and nitrate reabsorption in healthy subjects and in patients undergoing cardiac surgery: Risk of nitric oxide (NO) bioavailability loss by NAC? Int J Cardiol 2014; 177:30-3. [DOI: 10.1016/j.ijcard.2014.09.109] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 09/20/2014] [Indexed: 02/07/2023]
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Plasma homoarginine (hArg) and asymmetric dimethylarginine (ADMA) in patients with rheumatoid arthritis: Is homoarginine a cardiovascular corrective in rheumatoid arthritis, an anti-ADMA? Int J Cardiol 2014; 176:1129-31. [DOI: 10.1016/j.ijcard.2014.07.296] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 07/27/2014] [Indexed: 11/19/2022]
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Tsikas D, Niemann J, Beckmann B. Tsikas et al. 15-deoxy-Δ12,14-PGJ2: An interesting but unapproachable pharmacological target [corrected]? Int J Cardiol 2014; 177:307-9. [PMID: 25217216 DOI: 10.1016/j.ijcard.2014.08.145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 08/26/2014] [Indexed: 01/13/2023]
Affiliation(s)
- Dimitrios Tsikas
- Center of Pharmacology and Toxicology, Hannover Medical School, Hannover, Germany.
| | - Jonas Niemann
- Center of Pharmacology and Toxicology, Hannover Medical School, Hannover, Germany
| | - Bibiana Beckmann
- Center of Pharmacology and Toxicology, Hannover Medical School, Hannover, Germany
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Determination of urine ionic composition with potentiometric multisensor system. Talanta 2014; 131:556-61. [PMID: 25281140 DOI: 10.1016/j.talanta.2014.08.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 08/06/2014] [Accepted: 08/11/2014] [Indexed: 11/20/2022]
Abstract
The ionic composition of urine is a good indicator of patient's general condition and allows for diagnostics of certain medical problems such as e.g., urolithiasis. Due to environmental factors and malnutrition the number of registered urinary tract cases continuously increases. Most of the methods currently used for urine analysis are expensive, quite laborious and require skilled personnel. The present work deals with feasibility study of potentiometric multisensor system of 18 ion-selective and cross-sensitive sensors as an analytical tool for determination of urine ionic composition. In total 136 samples from patients of Urolithiasis Laboratory and healthy people were analyzed by the multisensor system as well as by capillary electrophoresis as a reference method. Various chemometric approaches were implemented to relate the data from electrochemical measurements with the reference data. Logistic regression (LR) was applied for classification of samples into healthy and unhealthy producing reasonable misclassification rates. Projection on Latent Structures (PLS) regression was applied for quantitative analysis of ionic composition from potentiometric data. Mean relative errors of simultaneous prediction of sodium, potassium, ammonium, calcium, magnesium, chloride, sulfate, phosphate, urate and creatinine from multisensor system response were in the range 3-13% for independent test sets. This shows a good promise for development of a fast and inexpensive alternative method for urine analysis.
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Trettin A, Modun D, Madunic S, Vukovic J, Radman M, Batkai S, Thum T, Jordan J, Tsikas D. LC–MS/MS and GC–MS/MS measurement of plasma and urine di-paracetamol and 3-nitro-paracetamol: Proof-of-concept studies on a novel human model of oxidative stress based on oral paracetamol administration. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 959:71-81. [DOI: 10.1016/j.jchromb.2014.03.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 03/14/2014] [Accepted: 03/16/2014] [Indexed: 12/18/2022]
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Effects of paracetamol on NOS, COX, and CYP activity and on oxidative stress in healthy male subjects, rat hepatocytes, and recombinant NOS. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:212576. [PMID: 24799980 PMCID: PMC3988730 DOI: 10.1155/2014/212576] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 02/26/2014] [Indexed: 01/08/2023]
Abstract
Paracetamol (acetaminophen) is a widely used analgesic drug. It interacts with various enzyme families including cytochrome P450 (CYP), cyclooxygenase (COX), and nitric oxide synthase (NOS), and this interplay may produce reactive oxygen species (ROS). We investigated the effects of paracetamol on prostacyclin, thromboxane, nitric oxide (NO), and oxidative stress in four male subjects who received a single 3 g oral dose of paracetamol. Thromboxane and prostacyclin synthesis was assessed by measuring their major urinary metabolites 2,3-dinor-thromboxane B2 and 2,3-dinor-6-ketoprostaglandin F1α, respectively. Endothelial NO synthesis was assessed by measuring nitrite in plasma. Urinary 15(S)-8-iso-prostaglanding F2α was measured to assess oxidative stress. Plasma oleic acid oxide (cis-EpOA) was measured as a marker of cytochrome P450 activity. Upon paracetamol administration, prostacyclin synthesis was strongly inhibited, while NO synthesis increased and thromboxane synthesis remained almost unchanged. Paracetamol may shift the COX-dependent vasodilatation/vasoconstriction balance at the cost of vasodilatation. This effect may be antagonized by increasing endothelial NO synthesis. High-dosed paracetamol did not increase oxidative stress. At pharmacologically relevant concentrations, paracetamol did not affect NO synthesis/bioavailability by recombinant human endothelial NOS or inducible NOS in rat hepatocytes. We conclude that paracetamol does not increase oxidative stress in humans.
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