1
|
LI WF, YAN DW, JIN Y, LI HY, MA M, WU ZZ. Application of Mass Spectrometry in Analysis of Non-Enzymatic Glycation Proteins in Diabetic Blood. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2019. [DOI: 10.1016/s1872-2040(19)61197-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
2
|
Capturing hemoglobin on graphene sheet from sub-microliter whole blood for quantitative characterization by internal extractive electrospray ionization mass spectrometry. Talanta 2019; 202:436-442. [PMID: 31171205 DOI: 10.1016/j.talanta.2019.04.069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 03/25/2019] [Accepted: 04/27/2019] [Indexed: 11/21/2022]
Abstract
A disposable blood sampler, which is consisted of a sub-microliter whole blood collector and a graphene filter, loading graphene sheet to selectively capture hemoglobin from sub-microliter whole blood, was developed for both qualitative and quantitative characterization hemoglobin by internal extractive electrospray ionization mass spectrometry (iEESI-MS). The blood collector was elegantly fabricated in syringe-like fashion for precisely sampling tiny amounts (1.0 μL - 2%) of whole blood, which was immediately diluted by water inside the syringe and was then pressed through the graphene filter placed between the waste outlet and the syringe reservoir to capture the hemoglobin in the blood sample. Then the graphene with hemoglobin was directly eluted by a charged (+2.5 kV) solution (mathanol/water/formic acid, 48/48/4, v/v/v) to produce the hemoglobin ions for mass spectrometric analysis. Low detection-of-limit (19.3 mg L-1 (89.5 picomol)), acceptable linear response range (300-1500 mg L-1, R2 = 0.998), relative standard deviation (0.5-6.5%, n = 3), low sample consumption (≤1.0 μL) and a relatively high speed (≤4 min per sample, including the sample loading) were achieved, demonstrating that the graphene based iEESI-MS was an alternative choice for direct detection of hemoglobin in whole blood with minimal sample consumption.
Collapse
|
3
|
Redman EA, Ramos-Payan M, Mellors JS, Ramsey JM. Analysis of Hemoglobin Glycation Using Microfluidic CE-MS: A Rapid, Mass Spectrometry Compatible Method for Assessing Diabetes Management. Anal Chem 2016; 88:5324-30. [PMID: 27100069 DOI: 10.1021/acs.analchem.6b00622] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Diabetes has become a significant health problem worldwide with the rate of diagnosis increasing rapidly in recent years. Measurement of glycated blood proteins, particularly glycated hemoglobin (HbA1c), is an important diagnostic tool used to detect and manage the condition in patients. Described here is a method using microfluidic capillary electrophoresis with mass spectrometry detection (CE-MS) to assess hemoglobin glycation in whole blood lysate. Using denaturing conditions, the hemoglobin (Hb) tetramer dissociates into the alpha and beta subunits (α- and β-Hb), which are then separated via CE directly coupled to MS detection. Nearly baseline resolution is achieved between α-Hb, β-Hb, and glycated β-Hb. A second glycated β-Hb isomer that is partially resolved from β-Hb is detected in extracted ion electropherograms for glycated β-Hb. Glycation on α-Hb is also detected in the α-Hb mass spectrum. Additional modifications to the β-Hb are detected, including acetylation and a +57 Da species that could be the addition of a glyoxal moiety. Patient blood samples were analyzed using the microfluidic CE-MS method and a clinically used immunoassay to measure HbA1c. The percentage of glycated α-Hb and β-Hb was calculated from the microfluidic CE-MS data using peak areas generated from extracted ion electropherograms. The values for glycated β-Hb were found to correlate well with the HbA1c levels derived in the clinic, giving a slope of 1.20 and an R(2) value of 0.99 on a correlation plot. Glycation of human serum albumin (HSA) can also be measured using this technique. It was observed that patients with elevated glycated Hb levels also had higher levels of HSA glycation. Interestingly, the sample with the highest HbA1c levels did not have the highest levels of glycated HSA. Because the lifetime of HSA is shorter than Hb, this could indicate a recent lapse in glycemic control for that patient. The ability to assess both Hb and HSA glycation has the potential to provide a more complete picture of a patient's glycemic control in the months leading up to blood collection. The results presented here demonstrate that the microfluidic CE-MS method is capable of rapidly assessing Hb and HSA glycation from low volumes of whole blood with minimal sample preparation and has the potential to provide more information in a single analysis step than current technologies.
Collapse
|
4
|
Barnaby OS, Cerny RL, Clarke W, Hage DS. Comparison of modification sites formed on human serum albumin at various stages of glycation. Clin Chim Acta 2011; 412:277-85. [PMID: 21034726 PMCID: PMC3053033 DOI: 10.1016/j.cca.2010.10.018] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Revised: 10/18/2010] [Accepted: 10/20/2010] [Indexed: 01/22/2023]
Abstract
BACKGROUND Many of the complications encountered during diabetes can be linked to the non-enzymatic glycation of proteins, including human serum albumin (HSA). However, there is little information regarding how the glycation pattern of HSA changes as the total extent of glycation is varied. The goal of this study was to identify and conduct a semi-quantitative comparison of the glycation products on HSA that are produced in the presence of various levels of glycation. METHODS Three glycated HSA samples were prepared in vitro by incubating physiological concentrations of HSA with 15 mmol/l glucose for 2 or 5 weeks, or with 30 mmol/l glucose for 4 weeks. These samples were then digested and examined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify the glycation products that were formed. RESULTS It was found that the glycation pattern of HSA changed with its overall extent of total glycation. Many modifications including previously-reported primary glycation sites (e.g., K199, K281, and the N-terminus) were consistently found in the tested samples. Lysines 199 and 281, as well as arginine 428, contained the most consistently identified and abundant glycation products. Lysines 93, 276, 286, 414, 439, and 524/525, as well as the N-terminus and arginines 98, 197, and 521, were also found to be modified at various degrees of HSA glycation. CONCLUSIONS The glycation pattern of HSA was found to vary with different levels of total glycation and included modifications at the 2 major drug binding sites on this protein. This result suggests that different modified forms of HSA, both in terms of the total extent of glycation and glycation pattern, may be found at various stages of diabetes. The clinical implication of these results is that the binding of HSA to some drug may be altered at various stages of diabetes as the extent of glycation and types of modifications in this protein are varied.
Collapse
Affiliation(s)
- Omar S. Barnaby
- Department of Chemistry, University of Nebraska, Lincoln, NE
| | - Ronald L. Cerny
- Department of Chemistry, University of Nebraska, Lincoln, NE
| | - William Clarke
- Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD
| | - David S. Hage
- Department of Chemistry, University of Nebraska, Lincoln, NE
| |
Collapse
|
5
|
Barnaby OS, Wa C, Cerny RL, Clarke W, Hage DS. Quantitative analysis of glycation sites on human serum albumin using (16)O/(18)O-labeling and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Clin Chim Acta 2010; 411:1102-10. [PMID: 20394739 DOI: 10.1016/j.cca.2010.04.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 04/06/2010] [Accepted: 04/07/2010] [Indexed: 11/27/2022]
Abstract
BACKGROUND One of the long term complications of diabetes is the non-enzymatic addition of glucose to proteins in blood, such as human serum albumin (HSA), which leads to the formation of an Amadori product and advanced glycation end products (AGEs). This study uses (16)O/(18)O-labeling and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to provide quantitative data on the extent of modification that occurs in the presence of glucose at various regions in the structure of minimally glycated HSA. METHODS Normal HSA, with no significant levels of glycation, was digested by various proteolytic enzymes in the presence of water, while a similar sample containing in vitro glycated HSA was digested in (18)O-enriched water. These samples were then mixed and the (16)O/(18)O ratios were measured for peptides in each digest. The values obtained for the (16)O/(18)O ratios of the detected peptides for the mixed sample were used to determine the degree of modification that occurred in various regions of glycated HSA. RESULTS Peptides containing arginines 114, 81, or 218 and lysines 413, 432, 159, 212, or 323 were found to have (16)O/(18)O ratios greater than a cut off value of 2.0 (i.e., a cut off value based on results noted when using only normal HSA as a reference). A qualitative comparison of the (16)O- and (18)O-labeled digests indicated that lysines 525 and 439 also had significant degrees of modification. The modifications that occurred at these sites were variations of fructosyl-lysine and AGEs which included 1-alkyl-2-formyl-3,4-glycoyl-pyrole and pyrraline. CONCLUSIONS Peptides containing arginine 218 and lysines 212, 413, 432, and 439 contained high levels of modification and are also present near the major drug binding sites on HSA. This result is clinically relevant because it suggests the glycation of HSA may alter its ability to bind various drugs and small solutes in blood.
Collapse
Affiliation(s)
- Omar S Barnaby
- Department of Chemistry, University of Nebraska, Lincoln, NE, United States
| | | | | | | | | |
Collapse
|
6
|
Williams JP, Jackson H, Green BN. Hb Belleville [β10(A7)Ala→Thr] Affects The Determination of Hb A 1cby Routine Cation Exchange High Performance Liquid Chromatography. Hemoglobin 2009; 33:45-50. [DOI: 10.1080/03630260802625915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
7
|
Monaci L, van Hengel AJ. Effect of heat treatment on the detection of intact bovine beta-lactoglobulins by LC mass spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:2985-92. [PMID: 17381107 DOI: 10.1021/jf063083x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Lactoglobulin (LG) is the most abundant protein of the whey fraction of cow's milk, and due to its high nutritional value as well as its technological properties it is widely used as an ingredient in food preparation. As a consequence of heat treatment, milk proteins may undergo structural changes such as protein unfolding and aggregation, in addition to chemical modifications. This, in turn can change the allergenic potential of LG. In this study, the potential of mass spectrometry has been exploited to investigate LG protein modification and stability as a consequence of thermal treatments applied to both standard solutions and milk samples. An investigation into the charge-state distribution in ESI-MS source revealed that, in standard solutions, a higher degree of protonation accompanies increases in the severity of the heat treatment applied. In contrast, the analysis of milk samples revealed a higher stability of the charge-state distribution of LG. However, we observed modification of LG spectra after heating of standard solutions as well as milk samples caused by lactosylation. The degree of LG lactosylation has been investigated in raw milk samples by LC-MS and provides a potential marker to trace heat treatments.
Collapse
Affiliation(s)
- Linda Monaci
- European Commission, Directorate General Joint Research Centre, Institute for Reference Material and Measurements, Retieseweg 111, B-2440 Geel, Belgium
| | | |
Collapse
|
8
|
Delpierre G, Veiga-da-Cunha M, Vertommen D, Buysschaert M, Van Schaftingen E. Variability in erythrocyte fructosamine 3-kinase activity in humans correlates with polymorphisms in the FN3K gene and impacts on haemoglobin glycation at specific sites. DIABETES & METABOLISM 2006; 32:31-9. [PMID: 16523184 DOI: 10.1016/s1262-3636(07)70244-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Part of the fructosamines that are bound to intracellular proteins are repaired by fructosamine 3-kinase (FN3K). Because subject-to-subject variations in erythrocyte FN3K activity could affect the level of glycated haemoglobin independently of differences in blood glucose level, we explored if such variability existed, if it was genetically determined by the FN3K locus on 17q25 and if the FN3K activity correlated inversely with the level of glycated haemoglobin. RESULTS The mean erythrocyte FN3K activity did not differ between normoglycaemic subjects (n = 26) and type 1 diabetic patients (n = 31), but there was a wide interindividual variability in both groups (from about 1 to 4 mU/g haemoglobin). This variability was stable with time and associated (P < 0.0001) with two single nucleotide polymorphisms in the promoter region and exon 6 of the FN3K gene. There was no significant correlation between FN3K activity and the levels of HbA1c, total glycated haemoglobin (GHb) and haemoglobin fructoselysine residues, either in the normoglycaemic or diabetic group. However, detailed analysis of the glycation level at various sites in haemoglobin indicated that the glycation level of Lys-B-144 was about twice as high in normoglycaemic subjects with the lowest FN3K activities as compared to those with the highest FN3K activities. CONCLUSION Interindividual variability of FN3K activity is substantial and impacts on the glycation level at specific sites of haemoglobin, but does not detectably affect the level of HbA1c or GHb. As FN3K opposes one of the chemical effects of hyperglycaemia, it would be of interest to test whether hypoactivity of this enzyme favours the development of diabetic complications.
Collapse
Affiliation(s)
- G Delpierre
- Laboratory of Physiological Chemistry, ICP and Université catholique de Louvain, Brussels, Belgium
| | | | | | | | | |
Collapse
|
9
|
Guy PA, Fenaille F. Contribution of mass spectrometry to assess quality of milk-based products. MASS SPECTROMETRY REVIEWS 2006; 25:290-326. [PMID: 16369930 DOI: 10.1002/mas.20074] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The vast knowledge of milk chemistry has been extensively used by the dairy manufacturing industry to develop and optimize the modern technology required to produce high-quality milk products to which we are accustomed. A thorough understanding of the chemistry of milk and its numerous components is essential for designing processing equipment and conditions needed for the manufacture and distribution of high-quality dairy products. Knowledge and application of milk chemistry is also indispensable for fractionating milk into its principal components for use as functional and nutritional ingredients by the food industry. For all these reasons, powerful analytical methods are required. Because of the complexity of the milk matrix, mass spectrometry, coupled or not to separation techniques, constitutes a key tool in this area. In the present manuscript, we review the contribution and potentialities of mass spectrometry-based techniques to assess quality of milk-based products.
Collapse
Affiliation(s)
- Philippe A Guy
- Department of Quality and Safety Assurance, Nestlé Research Center, Lausanne, Switzerland.
| | | |
Collapse
|
10
|
Gasthuys M, Alves S, Fenaille F, Tabet JC. Simple Identification of A Cross-Linked Hemoglobin by Tandem Mass Spectrometry in Human Serum. Anal Chem 2004; 76:6628-34. [PMID: 15538786 DOI: 10.1021/ac049275d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hemoglobin-based oxygen therapeutics are prepared by reaction of hemoglobin with cross-linking molecules and are utilized as blood substitutes. They can be used as doping agents to increase the oxygen-carrying capacity of hemoglobin. We have compared a glutaraldehyde-polymerized bovine hemoglobin (Oxyglobin, Biopure Corp.) with natural bovine hemoglobin by mass spectrometry in order to detect specific fragment ions of the cross-linked protein for further potential applications in doping control of human blood samples. HCl acid (6 N) hydrolysis was performed in parallel on both proteins. Hydrolysates were then analyzed by direct infusion electrospray mass spectrometry (ESIMS) using a triple quadrupole mass spectrometer. Confirmation and precision were obtained by LC-ESIMS(n) experiments performed on an ion trap mass spectrometer. Chromatographic and mass spectrometry data allowed detection of two potential Oxyglobin-specific ions--m/z 299 and 399--that were shown to lose a 159 u neutral fragment under collision-induced dissociation conditions. Thus, monitoring of constant neutral loss of 159 u on acid hydrolysates of human serum samples spiked with different amounts of Oxyglobin has proved to be an efficient screening method to specifically detect and identify Oxyglobin. LC-MS of the spiked serum sample hydrolysates enabled detection of Oxyglobin at a detection limit of 4 g x L(-1).
Collapse
Affiliation(s)
- Maryline Gasthuys
- LCSOB, University Pierre et Marie Curie, Boite 45, 4 place Jussieu 75252 Paris Cedex 05, France
| | | | | | | |
Collapse
|
11
|
Fenaille F, Campos-Giménez E, Guy PA, Schmitt C, Morgan F. Monitoring of beta-lactoglobulin dry-state glycation using various analytical techniques. Anal Biochem 2003; 320:144-8. [PMID: 12895479 DOI: 10.1016/s0003-2697(03)00357-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- François Fenaille
- Nestlé Research Center, Nestec Ltd., Vers-Chez-Les-Blanc, Lausanne, Switzerland
| | | | | | | | | |
Collapse
|
12
|
Fenaille F, Morgan F, Parisod V, Tabet JC, Guy PA. Solid-state glycation of beta-lactoglobulin monitored by electrospray ionisation mass spectrometry and gel electrophoresis techniques. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2003; 17:1483-1492. [PMID: 12820216 DOI: 10.1002/rcm.1077] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Glycation of beta-lactoglobulin (beta-Lg) with either lactose or galactose in a solid-state medium was monitored using gel electrophoresis techniques and liquid chromatography coupled to electrospray ionisation mass spectrometry (LC/ESI-MS). The kinetics of glycation monitored by SDS polyacrylamide gel electrophoresis showed a molecular weight increase over time of the beta-Lg bands for both sugars, but no significant amounts of aggregated proteins were observed. The isoelectric point of the protein, observed by isoelectric focusing gel electrophoresis, was dramatically affected by galactosylation. LC/MS measurements of beta-Lg variants A and B, over the whole glycation reaction time, showed a larger extent of glycation with galactose (from 4 up to 22 adducts) as compared with lactose (from 0 up to 14 adducts), and confirmed that early Maillard reaction products were the main species observed. Based on the relative abundances obtained from the deconvoluted mass spectra after a 8 h 15 min incubation time at 60 degrees C, the mean values of lactose and galactose molecules bound to the protein species were calculated to be 10.4 and 17.9, and 10.5 and 18.6, for variants A and B, respectively. Furthermore, the charge state distribution data obtained by ESI-MS was studied using different methanol percentages, and indicated that adduct formation with lactose, but more significantly galactose, tends to improve the stability properties of the native protein towards denaturation.
Collapse
Affiliation(s)
- François Fenaille
- Nestlé Research Center, Nestec Ltd., Vers-Chez-Les-Blanc, 1000 Lausanne 26, Switzerland
| | | | | | | | | |
Collapse
|
13
|
Nakanishi T, Miyazaki A, Shimizu A, Yamaguchi A, Nishimura S. Assessment of the effect of hemoglobin variants on routine HbA1c measurements by electrospray ionization mass spectrometry. Clin Chim Acta 2002; 323:89-101. [PMID: 12135809 DOI: 10.1016/s0009-8981(02)00183-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We applied electrospray ionization mass spectrometry (ESI-MS) to identify hemoglobin (Hb) variants, and to assess the effect of the variants on routine measurements of a glycated Hb, HbA1c. Over the past 8 years, we have diagnosed 83 cases, including 42 kinds of variant Hb, using MS as the main technology. Of these variants, 3 were new, and 9 were the first cases in Japan. Some abnormal Hbs cause diseases, and most cause erroneous values of HbA1c measured by various methods. ESI-MS was also successfully used for the accurate determination of glycated Hb. We and other groups proposed methods to examine glycated Hb by ESI-MS using enzyme-digested peptides, or intact globin without enzyme digestion. Using the peptide method, we clarified the extent of discrepancies among the HbA1c values measured by conventional methods and accurate values for samples containing various Hb variants identified by the MS method. We applied the globin method to measure the ratio of the glycated component of a variant chain and that of a normal chain obtained from the same erythrocytes. Although the glycation degree on most variant chains was similar to that on normal chains obtained from the same erythrocytes, the content of the glycated component of a particular variant beta-chain was approximately three times as much as that of the normal beta-chain. Abnormal Hbs cause erroneous values for HbA1c to various extents with commercial measurement methods, and MS may offer an unrivaled strategy to correct these errors.
Collapse
Affiliation(s)
- Toyofumi Nakanishi
- Department of Clinical Pathology, Osaka Medical College, 2-7, Daigaku-cho, Osaka, 569-8686, Takatsuki, Japan
| | | | | | | | | |
Collapse
|
14
|
Shimizu A, Nakanishi T, Kishikawa M, Miyazaki A. Detection and identification of protein variants and adducts in blood and tissues: an application of soft ionization mass spectrometry to clinical diagnosis. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 776:15-30. [PMID: 12127321 DOI: 10.1016/s1570-0232(02)00031-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The detection and identification of protein variants and abnormally increased modified proteins are important for clinical diagnosis. We applied soft ionization mass spectrometry (MS) to analyze proteins in blood and tissues from various patients. Over the past 8 years, we diagnosed 132 cases (55 kinds) of variant proteins including hemoglobin (Hb), transthyretin (TTR), and Cu/Zn-superoxide dismutase (SOD-1), using MS as the leading technology. Of these variants, eight were new, and nine were the first cases in Japan. Some abnormal Hb cause diseases, and most of them cause erroneous levels of glycated Hb, HbA1c, i.e., a popular index of diabetes. Most of the variant TTR causes amyloidotic polyneuropathy. Variant SOD-1 causes amyotrophic lateral sclerosis. We first showed that immunoprecipitation by a specific antiserum is a reliable and simple method to prepare protein from sera and tissues for analysis by matrix-assisted laser desorption time-of-flight MS, and liquid chromatography-electrospray ionization MS (LC-ESI-MS). The use of this technology has become widespread. Using an immunoprecipitated target protein and LC-ESI-MS, we showed that the ratios of tetra-, di- and a-sialo-transferrin from two cases of congenital glycoprotein deficient syndrome were clearly distinguishable from those of control samples. We first reported a unique modified form of TTR, that is, S-sulfonated TTR, which increased markedly and specifically in three cases with molibdenum cofactor deficiency. We proposed that S-sulfonated TTR is a useful marker for screening this disease. ESI-MS was successfully used for the accurate determination of HbA1c, and we clarified the extent of discrepancies between the HbA1c value measured by conventional methods and the accurate values for samples containing various Hb variants determined by the MS method.
Collapse
Affiliation(s)
- Akira Shimizu
- Department of Clinical Pathology, Osaka Medical College, 2-7 Daigakucho, Takatsuki City, Osaka 569-8686, Japan.
| | | | | | | |
Collapse
|
15
|
Zhang X, Medzihradszky KF, Cunningham J, Lee PD, Rognerud CL, Ou CN, Harmatz P, Witkowska HE. Characterization of glycated hemoglobin in diabetic patients: usefulness of electrospray mass spectrometry in monitoring the extent and distribution of glycation. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 759:1-15. [PMID: 11499613 DOI: 10.1016/s0378-4347(01)00196-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A combination of chromatographic and mass spectrometric techniques was used to evaluate the extent and distribution of glycation within the glycated hemoglobin (GHb) molecule. Studies on quantification of hemoglobin (Hb) glycation by electrospray ionization mass spectrometry (ES-MS) of intact globins employed specimens from 10 diabetic individuals and five normal controls. Detailed structural analysis of the phenylboronate affinity chromatography/ion-exchange (IE) HPLC-separated sub-populations of GHb was performed on a specimen carrying 13.7% GHb. An efficient protocol for mapping glycation sites within alpha and beta globins was developed, e.g., Glu-C/Asp-N proteolytic digestion followed by LC-ES-MS. Relative site occupancy within discrete components of GHb was evaluated. A correlation between the degree of glycation measured at Hb level (by affinity chromatography) and at globin level (measured by ES-MS) was carried out. The above studies led us to conclude that during the process of phenylboronate chromatography GHb dimers, rather than tetramers, are bound to the affinity resin so a fraction of glycated dimers rather than tetramers is measured. This finding implies that a process of glycation affects a much higher number of native Hb tetramers than was previously contemplated. No glycation sites appear to be missed by phenylboronate affinity chromatography. We have found no evidence of the presence of multiple glycations within a single globin chain. While glycation of both globins within a dimer cannot be excluded, it is unlikely to be a significant phenomenon. According to ES-MS data, an equivalent of about one globin per alphabeta dimer of the affinity chromatography-isolated GHb carried glycation.
Collapse
Affiliation(s)
- X Zhang
- Children's Hospital Oakland Research Institute, CA 94609, USA
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Venkatraman J, Aggarwal K, Balaram P. Helical peptide models for protein glycation: proximity effects in catalysis of the Amadori rearrangement. CHEMISTRY & BIOLOGY 2001; 8:611-25. [PMID: 11451663 DOI: 10.1016/s1074-5521(01)00036-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Non-enzymatic glycation of proteins has been implicated in various diabetic complications and age-related disorders. Proteins undergo glycation at the N-terminus or at the epsilon-amino group of lysine residues. The observation that only a fraction of all lysine residues undergo glycation indicates the role of the immediate chemical environment in the glycation reaction. Here we have constructed helical peptide models, which juxtapose lysine with potentially catalytic residues in order to probe their roles in the individual steps of the glycation reaction. RESULTS The peptides investigated in this study are constrained to adopt helical conformations allowing residues in the i and i+4 positions to come into spatial proximity, while residues i and i+2 are far apart. The placing of aspartic acid and histidine residues at interacting positions with lysine modulates the steps involved in early peptide glycation (reversible Schiff base formation and its subsequent irreversible conversion to a ketoamine product, the Amadori rearrangement). Proximal positioning of aspartic acid or histidine with respect to the reactive lysine residue retards initial Schiff base formation. On the contrary, aspartic acid promotes catalysis of the Amadori rearrangement. Presence of the strongly basic residue arginine proximate to lysine favorably affects the pK(a) of both the lysine epsilon-amino group and the singly glycated lysine, aiding in the formation of doubly glycated species. The Amadori product also formed carboxymethyl lysine, an advanced glycation endproduct (AGE), in a time-dependent manner. CONCLUSIONS Stereochemically defined peptide scaffolds are convenient tools for studying near neighbor effects on the reactivity of functional amino acid sidechains. The present study utilizes stereochemically defined peptide helices to effectively demonstrate that aspartic acid is an efficient catalytic residue in the Amadori arrangement. The results emphasize the structural determinants of Schiff base and Amadori product formation in the final accumulation of glycated peptides.
Collapse
Affiliation(s)
- J Venkatraman
- Molecular Biophysics Unit, Indian Institute of Science, Banglore, India
| | | | | |
Collapse
|
17
|
Roberts NB, Amara AB, Morris M, Green BN. Long-Term Evaluation of Electrospray Ionization Mass Spectrometric Analysis of Glycated Hemoglobin. Clin Chem 2001. [DOI: 10.1093/clinchem/47.2.316] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Background: Electrospray ionization mass spectrometry (ESIMS) has been successfully applied to the identification of hemoglobin (Hb) variants and the presence of glucose adducts (mass difference of 162 Da) on the separate Hb α and β chains. To establish the potential of ESIMS as a routine and/or a reference method for the quantification of glycohemoglobin (HbA1c), we carried out a detailed evaluation over a 4-month period in a routine laboratory environment.
Methods: We optimized a procedure using ESIMS suitable for the routine quantitative analysis of HbA1c. We determined reliability and reproducibility over 4 months and assessed the potential for automated sample injection. We then compared values of 1022 blood samples from diabetic patients with a routine HPLC-based ion-exchange procedure (HA-8140; Menarini).
Results: Results of HbA1c measurement by ESIMS were available within 3 min. The analytical imprecision (CV) was 1.6–5.0% for both manual and automated injections. Data collection over the m/z 980-1400 range confirmed lower glycation of the α chain relative to the β chain (0.66:1). Only one glycation was observed per globin chain. The overall glycohemoglobin (i.e., the average of α- and β-chain glycations) measured by ESIMS (x) on 1022 blood samples was lower than by HPLC (y): y = 1.0432x + 0.4815. However, the β-chain glycation measured by ESIMS was up to 20% higher than the value measured by ion-exchange HPLC and showed a close conformity, particularly at 5–10% HbA1c, with the ion-exchange Diabetes Control and Complications Trial (DCCT)-corrected and the United Kingdom National External Quality Assessment Scheme DCCT mean return values.
Conclusions: ESIMS provides a precise measurement of HbA1c and, in particular, glycation of the β chain. The method is robust and could be proposed as a procedure to substantiate HbA1c measurement and/or calibration.
Collapse
Affiliation(s)
- Norman B Roberts
- Department of Clinical Chemistry, Royal Liverpool University Hospital, Liverpool L7 8XP, United Kingdom
| | - Alieu B Amara
- Department of Clinical Chemistry, Royal Liverpool University Hospital, Liverpool L7 8XP, United Kingdom
| | - Michael Morris
- Micromass (UK) Ltd., Wythenshawe, Manchester M239LZ, United Kingdom
| | - Brian N Green
- Micromass (UK) Ltd., Wythenshawe, Manchester M239LZ, United Kingdom
| |
Collapse
|
18
|
Nakanishi T, Shimizu A. Determination of ionization efficiency of glycated and non-glycated peptides from the N-terminal of hemoglobin beta-chain by electrospray ionization mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 746:83-9. [PMID: 11048743 DOI: 10.1016/s0378-4347(00)00115-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We compared the ionization efficiency of glycated and non-glycated peptides for the HbA1c measurement method developed by Kobold et al. [Clin. Chem., 43 (1997) 1944] based on LC-ESI-MS analysis of the N-terminal peptides of the beta-chains released by cleavage of the hemoglobin with endoproteinase Glu-C. Taking half the peak area of the doubly charged ion and adding it to the area of the singly charged ion, we determined that the slope of the resulting calibration curve was nearly equal to 1, and the reproducibility of the added values was better than the values calculated by the doubly or the singly charged ion alone.
Collapse
Affiliation(s)
- T Nakanishi
- Department of Clinical Pathology, Osaka Medical College, Takatsuki, Japan
| | | |
Collapse
|
19
|
Feng B, Smith RD. A simple nanoelectrospray arrangement with controllable flowrate for mass analysis of submicroliter protein samples. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2000; 11:94-99. [PMID: 10631670 DOI: 10.1016/s1044-0305(99)00124-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A simple arrangement for nanoelectrospray ionization using a conventional syringe pump connected to a pulled unmodified capillary has been evaluated. This arrangement avoids several disadvantages associated with metal-coated nanoelectrospray emitters. The relatively large orifice (approximately 9 microns) at the pulled capillary tip reduces sample clogging and the use of the pump minimizes spray disruption due to gas bubbles. Subattomole detection limit was achieved with nanomolar protein sample solutions at 5-10 nL/min flowrates using an LCQ mass spectrometer. Submicroliter samples can be loaded from the tip orifice and stored inside the capillary to virtually eliminate any dead volume, and then be electrosprayed for extended periods at well-controlled flowrates.
Collapse
Affiliation(s)
- B Feng
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | | |
Collapse
|
20
|
Saraswathi M, Nakanishi T, Shimizu A. Relative quantification of glycated Cu-Zn superoxide dismutase in erythrocytes by electrospray ionization mass spectrometry. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1426:483-90. [PMID: 10076065 DOI: 10.1016/s0304-4165(98)00171-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Electrospray ionization mass spectrometry (ESIMS) was used for relative quantification of glycated Cu-Zn superoxide dismutase (SOD-1) in human erythrocytes. SOD-1 samples were prepared from erythrocytes by removing hemoglobin using hemoglobind gel followed by ethanol and chloroform extraction. The reproducibility in measurement of the relative percentage of glycated protein was good, and the standard deviation of each measurement was 4.0%. From the mass spectral analysis of a mixture of commercial SOD-1 and in vitro partially glycated SOD-1 in several ratios, it was found that free and glycated SOD-1 have the same ionization efficiencies. The percentage of glycation on SOD-1 was measured in 30 individuals, including patients with diabetes mellitus. The glycation levels ranged from 4.5% to below the detection limit. The SOD-1 sample extracted from erythrocytes was fractionated by Glyco-Gel B chromatography, and the separated fractions were analyzed by MS. The mass spectra of absorbed fraction showed significant amounts of non-specific binding of non-glycated proteins to Glyco-Gel B.
Collapse
Affiliation(s)
- M Saraswathi
- Department of Clinical Pathology, Osaka Medical College, 2-7 Daigaku-cho, Takatsuki-city, Osaka 569-8686, Japan
| | | | | |
Collapse
|
21
|
Lapolla A, Fedele D, Plebani M, Garbeglio M, Seraglia R, D'Alpaos M, Aricò CN, Traldi P. Direct evaluation of glycated and glyco-oxidized globins by matrix-assisted laser desorption/ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1999; 13:8-14. [PMID: 9921686 DOI: 10.1002/(sici)1097-0231(19990115)13:1<8::aid-rcm438>3.0.co;2-h] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Matrix-assisted laser desorption ionization (MALDI) mass spectrometry (MS) has been applied to achieve a qualitative and quantitative evaluation of glycated globins on a wide number of healthy and diabetic subjects. The method allowed us to establish that both alpha- and beta-globins are glycated and that, in addition to simply glycated products, other species are detected. Investigations by different sample treatments and by analysis of the glycated beta-globin fraction obtained by preparative chromatography indicated that these species correspond to glyco-oxidized globins. Consequently MALDI-MS can be validly employed to evaluate not only the glycation level, but also the degree of oxidative stress. The percentages of glycated and glycooxidized species were calculated from the related MALDI spectra by the measurement of the related peak areas, without any other treatment of data. A linear relationship between HbA1c values and the total percentage of glycated and glyco-oxidized globins has been found, and its slope (< 1) has been rationalized by the uncorrected evaluation of glycated globins content in the standard samples employed for HbA1c measurements.
Collapse
Affiliation(s)
- A Lapolla
- Istituto di Medicina Interna, Malattie del Metabolismo, Padova, Italy
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Nakanishi T, Miyazaki A, Kishikawa M, Shimizu A, Kishida O, Sumi S, Tsubakio T, Imai K. A new hemoglobin variant found during Hb A1c measurement: Hb Hokusetsu [beta52(D3)Asp-->Gly]. Hemoglobin 1998; 22:355-71. [PMID: 9730366 DOI: 10.3109/03630269809071530] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A new beta chain variant was accidentally found through the assay of Hb A1c in a diabetic patient. The variant was detected by polyacrylamide gel isoelectrofocusing and electrospray ionization mass spectrometry. For sequence determination, globin was cleaved with combination of trypsin and lysyl endopeptidase and analyzed by high performance liquid chromatography connected to electrospray ionization mass spectrometry. An abnormal betaT-5 peptide was found by reconstructed selected ion monitoring. The collision-induced dissociation spectrum of an ion derived from the abnormal betaT-5 peptide revealed a new substitution, [beta52(D3)Asp-->Gly], named Hb Hokusetsu. The sequence was confirmed with an automatic sequencer using peptides isolated by reversed phase high performance liquid chromatography. Amplification of the beta-globin exon 2 and nucleotide sequencing revealed a GAT-->GGT mutation in codon 52 corresponding to an Asp-->Gly replacement. Electrospray ionization mass spectrometry analysis of the hemolysate showed a reasonable value of 10.4% for glycated globin. The variant migrated as Hb S on isoelectrofocusing. Hematological analysis revealed normal parameters. The patient's hemolysate showed normal stability in the isopropanol test. Oxygen equilibrium studies on the patient's red blood cells and hemolysate showed no significant change in oxygen affinity or cooperativity.
Collapse
Affiliation(s)
- T Nakanishi
- Department of Clinical Pathology, Osaka Medical College, Takatsuki, Japan
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Nakanishi T, Kishikawa M, Miyazaki A, Shimizu A, Ogawa Y, Sakoda S, Ohi T, Shoji H. Simple and defined method to detect the SOD-1 mutants from patients with familial amyotrophic lateral sclerosis by mass spectrometry. J Neurosci Methods 1998; 81:41-4. [PMID: 9696308 DOI: 10.1016/s0165-0270(98)00012-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mutations in Cu/Zn superoxide dismutase (SOD1) cause a subset of cases of familial amyotrophic lateral sclerosis (FALS). We established a simple and defined method to detect the mutant SODI in erythrocytes by electrospray ionization mass spectrometry (ESIMS) using materials precipitated with specific antiserum. Hemolysate was mixed with anti-SOD1 antiserum and the generated precipitate, which was soluble in the solvent for MS analysis, was injected on to an LC column connected to an ESI-mass spectrometer. MS spectra of the reduced SOD1 prepared from normal individuals showed ion peaks corresponding to free monomer SOD1. The spectra from FALS patients revealed doublet ion peaks corresponding to normal and mutant components. The ratios of mutant to normal SOD1 were about 1/2 in cases of (G37R) and (A4S), and about 0.15 in a case of (H46R). This method provides for the rapid diagnosis using small amount of specimens, and will contribute to elucidate the pathomechanism of FALS through the quantification of SOD1 mutants in erythrocytes and in tissues of nervous systems.
Collapse
Affiliation(s)
- T Nakanishi
- Department of Clinical Pathology, Osaka Medical College, Takatsuki, Japan
| | | | | | | | | | | | | | | |
Collapse
|