1
|
Orekhov A, Khotina V, Sukhorukov V, Sobenin I. Non-oxidative vs Oxidative Forms of Modified Low-density Lipoprotein: What is More Important in Atherogenesis? Curr Med Chem 2024; 31:2309-2313. [PMID: 38204226 DOI: 10.2174/0109298673294245240102105814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/15/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024]
Affiliation(s)
- Alexander Orekhov
- Institute of General Pathology and Pathophysiology, 8 Baltiiskaya Street, Moscow, 125315, Russia
| | | | - Vasily Sukhorukov
- Institute of General Pathology and Pathophysiology, 8 Baltiiskaya Street, Moscow, 125315, Russia
| | - Igor Sobenin
- Institute of General Pathology and Pathophysiology, 8 Baltiiskaya Street, Moscow, 125315, Russia
| |
Collapse
|
2
|
Benitez S, Puig N, Rives J, Solé A, Sánchez-Quesada JL. Can Electronegative LDL Act as a Multienzymatic Complex? Int J Mol Sci 2023; 24:ijms24087074. [PMID: 37108253 PMCID: PMC10138509 DOI: 10.3390/ijms24087074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/06/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Electronegative LDL (LDL(-)) is a minor form of LDL present in blood for which proportions are increased in pathologies with increased cardiovascular risk. In vitro studies have shown that LDL(-) presents pro-atherogenic properties, including a high susceptibility to aggregation, the ability to induce inflammation and apoptosis, and increased binding to arterial proteoglycans; however, it also shows some anti-atherogenic properties, which suggest a role in controlling the atherosclerotic process. One of the distinctive features of LDL(-) is that it has enzymatic activities with the ability to degrade different lipids. For example, LDL(-) transports platelet-activating factor acetylhydrolase (PAF-AH), which degrades oxidized phospholipids. In addition, two other enzymatic activities are exhibited by LDL(-). The first is type C phospholipase activity, which degrades both lysophosphatidylcholine (LysoPLC-like activity) and sphingomyelin (SMase-like activity). The second is ceramidase activity (CDase-like). Based on the complementarity of the products and substrates of these different activities, this review speculates on the possibility that LDL(-) may act as a sort of multienzymatic complex in which these enzymatic activities exert a concerted action. We hypothesize that LysoPLC/SMase and CDase activities could be generated by conformational changes in apoB-100 and that both activities occur in proximity to PAF-AH, making it feasible to discern a coordinated action among them.
Collapse
Affiliation(s)
- Sonia Benitez
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain
- CIBER of Diabetes and Related Metabolic Diseases (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Núria Puig
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain
- Biochemistry and Molecular Biology Department, Universitat Autònoma de Barcelona, 08193 Cerdanyola, Spain
| | - José Rives
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain
- Biochemistry and Molecular Biology Department, Universitat Autònoma de Barcelona, 08193 Cerdanyola, Spain
| | - Arnau Solé
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain
- Biochemistry and Molecular Biology Department, Universitat Autònoma de Barcelona, 08193 Cerdanyola, Spain
| | - José Luis Sánchez-Quesada
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain
- CIBER of Diabetes and Related Metabolic Diseases (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
| |
Collapse
|
3
|
Moreno-Gordaliza E, van der Lee SJ, Demirkan A, van Duijn CM, Kuiper J, Lindenburg PW, Hankemeier T. A novel method for serum lipoprotein profiling using high performance capillary isotachophoresis. Anal Chim Acta 2016; 944:57-69. [DOI: 10.1016/j.aca.2016.09.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 01/22/2023]
|
4
|
Bacterial surface layer proteins as a novel capillary coating material for capillary electrophoretic separations. Anal Chim Acta 2016; 923:89-100. [DOI: 10.1016/j.aca.2016.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/31/2016] [Accepted: 04/02/2016] [Indexed: 11/22/2022]
|
5
|
Development of a low-cost, high-throughput native polyacrylamide gel electrophoresis (N-PAGE) protocol for lipoprotein sub-fractionation using Quality by Design approach. J Pharm Biomed Anal 2014; 92:119-26. [DOI: 10.1016/j.jpba.2014.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/06/2014] [Accepted: 01/07/2014] [Indexed: 11/18/2022]
|
6
|
Sánchez-Quesada JL, Estruch M, Benítez S, Ordóñez-Llanos J. Electronegative LDL: a useful biomarker of cardiovascular risk? ACTA ACUST UNITED AC 2012. [DOI: 10.2217/clp.12.26] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
7
|
Urata J, Ikeda S, Koga S, Nakata T, Yasunaga T, Sonoda K, Koide Y, Ashizawa N, Kohno S, Maemura K. Negatively charged low-density lipoprotein is associated with atherogenic risk in hypertensive patients. Heart Vessels 2011; 27:235-42. [PMID: 21491122 DOI: 10.1007/s00380-011-0139-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Accepted: 03/18/2011] [Indexed: 02/02/2023]
Abstract
Negatively charged low-density lipoprotein (LDL), generated via multiple processes such as oxidation, acetylation, or glycosylation, plays a key role in the initiation and progression of atherosclerosis and related diseases. Anion-exchange high-performance liquid chromatography (AE-HPLC) can subfractionate LDL into LDL-1, LDL-2, and LDL-3 based on LDL particle charge, but the clinical significance of LDL subfractions has not yet been elucidated. The aim of this study was to determine the clinical significance of these fractions with particular regard to atherogenic risk in hypertensive patients. Ninety-eight patients with essential hypertension (age 67.0 ± 10.7 years; 54 males) were enrolled in the present study. The relationships between LDL subfractions and atherogenic risk factors, including lipid profiles, blood pressure and plasma 8-isoprostane as a marker of oxidative stress, were examined. LDL-1 levels were significantly and negatively correlated with body mass index (r = -0.384, p < 0.001), systolic blood pressure (r = -0.457, p < 0.001), non-high-density lipoprotein cholesterol levels (r = -0.457, p < 0.001) and 8-isoprostane levels (r = -0.415, p < 0.001). LDL-3, which is the most negatively charged fraction of total LDL, was significantly and positively correlated with these parameters (r = 0.267, 0.481, 0.357, and 0.337, respectively). LDL-1 levels were significantly lower (p < 0.001), and LDL-2 and LDL-3 levels were significantly higher (each p < 0.001) in patients with poorly controlled hypertension than in patients with well-controlled hypertension. In addition, an increase in the total number of traditional risk factors at time of study participation, but not previous diagnosis, was associated with a decrease in LDL-1 levels and increases in LDL-2 and LDL-3 levels. These data suggest that LDL subfractions are associated with multiple atherogenic risk factors and that treatment to modify these risk factors could result in changes in LDL subfraction levels. In conclusion, LDL subfractions isolated by AE-HPLC may represent a marker of atherogenic risk in patients with hypertension.
Collapse
Affiliation(s)
- Jungo Urata
- Department of Cardiovascular Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Characterization of in vitro modified human high-density lipoprotein particles and phospholipids by capillary zone electrophoresis and LC ESI-MS. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:3495-505. [DOI: 10.1016/j.jchromb.2009.08.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Revised: 08/07/2009] [Accepted: 08/12/2009] [Indexed: 11/22/2022]
|
9
|
Capillary isotachophoresis study of lipoprotein network sensitive to apolipoprotein E phenotype. 1. ApoE distribution between lipoproteins. Mol Cell Biochem 2009; 325:41-51. [DOI: 10.1007/s11010-008-0018-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Accepted: 12/30/2008] [Indexed: 10/21/2022]
|
10
|
Zhang B, Maeda N, Okada K, Tatsukawa M, Sawayama Y, Matsunaga A, Kumagai K, Miura SI, Nagao T, Hayashi J, Saku K. Association between fast-migrating low-density lipoprotein subfraction as characterized by capillary isotachophoresis and intima-media thickness of carotid artery. Atherosclerosis 2006; 187:205-12. [PMID: 16236285 DOI: 10.1016/j.atherosclerosis.2005.09.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2005] [Revised: 08/10/2005] [Accepted: 09/10/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND A mildly modified LDL subfraction that is characterized by an increased negative charge exists in plasma. This electronegative LDL separated by ion-exchange chromatography has been shown to be inflammatory and its proportion is increased in patients with hyperlipidemia and diabetes mellitus. The present study examined the association between the level of fast (f)-migrating LDL subfraction characterized by capillary isotachophoresis (cITP) and carotid-artery intima-media thickness (CA-IMT). METHODS AND RESULTS This study included 469 subjects who underwent a physical examination. CA-IMT was determined by high-resolution B-model ultrasonoraphy. Levels of charge-based LDL subfractions were measured by cITP on a Beckman P/ACE MDQ system. An increased serum LDL-C level and cITP fLDL level were associated with increased CA-IMT after adjusting for age. The extent of the associations between cITP fLDL and CA-IMT and between LDL-C and CA-IMT were similar as assessed by a receiver-operating characteristic curve analysis. LDL-C, triglyceride, and remnant-like particle cholesterol levels were independently correlated with cITP fLDL, and the LDL-C level had the strongest correlation with cITP fLDL. The association between the cITP fLDL level and CA-IMT was significant in the high LDL-C stratum but not in the low stratum, indicating that it is modified by the LDL-C level. The high-LDL-C-high-fLDL group had the highest relative risk for a high CA-IMT among the groups with each combination of LDL-C and cITP fLDL level. CONCLUSION The cITP fLDL level was associated with CA-IMT and its combination with the LDL-C level is a stronger indicator for a high CA-IMT.
Collapse
Affiliation(s)
- Bo Zhang
- Department of Cardiology, Fukuoka University School of Medicine, 7-45-1 Nanakuma Jonan-ku, Fukuoka 814-0180, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Menys VC, Liu Y, Mackness MI, Kwok S, Caslake MJ, Stewart G, Durrington PN. Isolation of plasma small-dense low-density lipoprotein using a simple air-driven ultracentrifuge and quantification using immunassay of apolipoprotein B. ACTA ACUST UNITED AC 2004; 42:30-6. [PMID: 15061377 DOI: 10.1515/cclm.2004.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractSmall-dense low-density lipoprotein (SD-LDL) is associated with coronary heart disease risk. Current methods for its quantification are expensive, complex and time-consuming. Plasma was adjusted to a density (D) of 1.044 g/ml in a volume of 0.18 ml and centrifuged in a Beckman Airfuge at 160 000×
Collapse
Affiliation(s)
- Valentine C Menys
- Department of Medicine, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL, UK.
| | | | | | | | | | | | | |
Collapse
|
12
|
Menys VC, Liu Y, Mackness MI, Caslake MJ, Kwok S, Durrington PN. Measurement of plasma small-dense LDL concentration by a simplified ultracentrifugation procedure and immunoassay of apolipoprotein B. Clin Chim Acta 2003; 334:95-106. [PMID: 12867279 DOI: 10.1016/s0009-8981(03)00231-6] [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: 11/26/2022]
Abstract
BACKGROUND Existing methods for detecting small-dense low-density lipoprotein (SD-LDL) are either semiquantitative (e.g., gradient gel electrophoresis) or require specialised laboratory methods (e.g., density-gradient ultracentrifugation, DGU). METHODS We report a method in which plasma was adjusted to a density (D) of 1.044 and 1.060 g/ml, respectively, in two tubes, both of which underwent ultracentrifugation (UC). A measure of SD-LDL apolipoprotein B (apo B) was obtained by subtraction of the apo B concentration in D>1.060 g/ml lipoproteins from that in D>1.044 g/ml lipoproteins to correct for apo B associated with lipoprotein (a) [Lp(a)]. This procedure was evaluated in paired plasma samples in healthy men (n=62) and in age-matched healthy women (n=74) and in age-matched primary dyslipidaemic men (n=72) and women (n=29) and compared with an established density-gradient ultracentrifugation (DGU) method. RESULTS The dyslipidaemic patients had either decreased high-density lipoprotein cholesterol (HDL-C) and/or increased triglycerides. In dyslipidaemic men, SD-LDL apo B level (23 [5-77] mg/dl) was significantly higher than in healthy men (P<0.001). In dyslipidaemic women, the SD-LDL apo B levels (11 [4-71] mg/dl) were significantly higher than in healthy women (7 [1-45] mg/dl; P<0.005). The concentration of SD-LDL apo B correlated inversely with HDL-C in both women (r=-0.280: P<0.005) and men (r=-0.464; P<0.0001) and positively with triglyceride concentration in both women (r=0.213; P<0.05) and men (r=0.592: P<0.0001). Correction for apo B in Lp(a) increased the analytical variation, which was 12% for apo B at D=1.044-1.060 g/ml and 9% for apo B measured at D>1.044 g/ml. Although the correlation between the new method and DGU results was high (r=0.830; P<0.0001, n=43), the concentration of apo B at D>1.044 g/ml correlated strongly with both corrected results (r=0.978; P<0.0001; n=237) and also with SD-LDL isolated using the DGU method (r=0.832; P<0.0001). Results at D>1.044 g/ml showed the expected correlations both with HDL-C (r=-0.465: P<0.0001) and triglycerides (r=0.526; P<0.0001). CONCLUSIONS The new method gave results consistent with earlier published findings using other techniques. Further simplification of the method using a single-density spin at D>1.044 g/ml appears feasible and may provide an easier quantitative method for clinical use.
Collapse
Affiliation(s)
- Valentine C Menys
- Department of Medicine, Manchester Royal Infirmary, Oxford Road, M13 9WL, Manchester, UK.
| | | | | | | | | | | |
Collapse
|
13
|
Dergunov AD, Hoy A, Smirnova EA, Visvikis S, Siest G. Charge-based heterogeneity of human plasma lipoproteins at hypertriglyceridemia: capillary isotachophoresis study. Int J Biochem Cell Biol 2003; 35:530-43. [PMID: 12565713 DOI: 10.1016/s1357-2725(02)00359-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
To reveal the metabolic links between and within pools of pro-atherogenic triglyceride(TG)-rich lipoproteins and anti-atherogenic high density lipoproteins (HDL), the changes in lipoprotein profile at hypertriglyceridemia were analyzed by capillary isotachophoresis. Plasma samples from patients with apoE3/3 phenotype were stained with a fluorescent probe NBD-C6-ceramide and lipoproteins resolved into six H-, one (V+I) and four L-components which belong to HDL, very low and intermediate density (VLDL+IDL) and low density lipoproteins (LDL), respectively. The expected correlation between the relative size of the combined fractions and lipid and apolipoprotein values was obtained confirming the validity of the approach. The new findings were obtained as follows. (1) The fast L-component correlated inversely with HDL-cholesterol (Chol), while intermediate and slow H-components correlated inversely with plasma and LDL-Chol and apoB. (2) The content of intermediate and slow H-components increased within H-pool and decreased relative TG-rich lipoproteins as hypertriglyceridemia rose due to the impairment of triglyceride hydrolysis by lipoprotein lipase within TG-rich particles. (3) A predictive value of the ratios of fast to slow H-components as an indicator of lecithin:cholesterol acyltransferase activity was demonstrated which tended to decrease at hypertriglyceridemia. (4) The L1/L2 ratio may be considered as an indicator of the accumulation of small dense LDL, which is a feature of clinically manifested atherogenic B-pattern. The competition between H(DL) and L(DL) particles for hepatic lipase and significant contribution of apoE to functional deficiency of H(DL) particles at hypertriglyceridemia are suggested.
Collapse
Affiliation(s)
- Alexander D Dergunov
- National Research Centre for Preventive Medicine, 10, Petroverigsky street, 101953, Moscow, Russia.
| | | | | | | | | |
Collapse
|
14
|
Petersen JR, Okorodudu AO, Mohammad A, Payne DA. Capillary electrophoresis and its application in the clinical laboratory. Clin Chim Acta 2003; 330:1-30. [PMID: 12636924 DOI: 10.1016/s0009-8981(03)00006-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Over the past 10 years, capillary electrophoresis (CE) is an analytical tool that has shown great promise in replacing many conventional clinical laboratory methods, especially electrophoresis and high performance liquid chromatography (HPLC). The main attraction of CE was that it was fast, used small amounts of sample and reagents, and was extremely versatile, being able to separate large and small analytes, both neutral and charged. Because of this versatility, numerous methods for clinically relevant analytes have been developed. However, with the exception of the molecular diagnostic and forensic laboratories CE has not had a major impact. A possible reason is that CE is still perceived as requiring above-average technical expertise, precluding its use in a laboratory workforce that is less technically adept. With the introduction of multicapillary instruments that are more automated, less technique-dependent, in addition to the availability of commercial and cost effective test kit methods, CE may yet be accepted as a instrument routinely used in the clinical laboratories. Thus, this review will focus on the areas where CE shows the most potential to have the greatest impact on the clinical laboratory. These include analysis of proteins found in serum, urine, CSF and body fluids, immunosubstraction electrophoresis, hemoglobin variants, lipoproteins, carbohydrate-deficient transferrin (CDT), forensic and therapeutic drug screening, and molecular diagnostics.
Collapse
Affiliation(s)
- John R Petersen
- Department of Pathology, University of Texas Medical Branch, Galveston, USA.
| | | | | | | |
Collapse
|
15
|
Yamaguchi Y, Kunitomo M, Haginaka J. Assay methods of modified lipoproteins in plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 781:313-30. [PMID: 12450666 DOI: 10.1016/s1570-0232(02)00433-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Modified lipoproteins, especially oxidatively modified low-density lipoprotein (Ox-LDL), are present in the plasma of patients with atherosclerosis and related diseases. The modification of LDL is believed to play an important role in the development of atherosclerosis. Thus, measurement of plasma Ox-LDL is essential not only for investigating its relevance to atherosclerotic diseases, but also for diagnosis. Chromatographic methods are effective for indirectly measuring the oxidatively modified state of LDL or directly measuring the modified LDL. Indirect determination can be done by estimating the LDL subfraction, LDL particle size, oxidized amino acids in apolipoprotein B, lipid hydroperoxide or F(2)-isoprostane in LDL. Direct determination of the modified LDL in plasma can be done with chromatographic methods such as anion-exchange chromatography and size-exclusion chromatography. Other methods for estimating the modified state of LDL include electromigration methods such as agarose gel, polyacrylamide gradient gel and capillary electrophoresis. Recently, enzyme-linked immunosorbent assay methods of malondialdehyde (MDA)-LDL and autoantibodies against Ox-LDL have been developed to assess Ox-LDL in plasma. This review article summarizes the detection and assay methods of modified lipoproteins in plasma.
Collapse
Affiliation(s)
- Yu Yamaguchi
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Mukogawa Women's University, 11-68, Koshien Kyuban-cho, Nishinomiya 663-8179, Japan.
| | | | | |
Collapse
|
16
|
Weiller BH, Ceriotti L, Shibata T, Rein D, Roberts MA, Lichtenberg J, German JB, de Rooij NF, Verpoorte E. Analysis of lipoproteins by capillary zone electrophoresis in microfluidic devices: assay development and surface roughness measurements. Anal Chem 2002; 74:1702-11. [PMID: 12033263 DOI: 10.1021/ac011096y] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The development of a new assay for lipoproteins by capillary electrophoresis in fused-silica capillaries and in glass microdevices is described in this paper. The separation of low-density (LDL) and high-density (HDL) lipoproteins by capillary zone electrophoresis is demonstrated in fused-silica capillaries with both UV absorption and laser-induced fluorescence detection. This separation was accomplished using Tricine buffer (pH 9.0) with methylglucamine added as a dynamic coating. With UV detection, LDL eluted as a relatively sharp peak with a migration time of approximately 11 min and HDL eluted as a broad peak with a migration time of 12.5 min. Fluorescence detection of lipoproteins stained with NBD-ceramide was used with the same buffer system to give comparable results. Furthermore, fluorescence staining of human serum samples yielded results similar to the fluorescently stained LDL and HDL fractions, showing that this method can be used to quantify lipoproteins in serum samples. The method was also used to detect lipoproteins in glass micro-CE devices. Very similar results were obtained in microdevices although with much faster analysis times, LDL eluted as a sharp peak at approximately 25 s and HDL as a broad peak at slightly longer time. In addition, higher resolution was obtained on chips. To our knowledge, these results show the first separation and detection of lipoproteins in a microfluidic device using native serum samples. Atomic force microscopy was used to characterize the rms surface roughness (Rq) of microfluidic channels directly. Devices with different surface roughness values were fabricated using two different etchants for Pyrex wafers with a polysilicon masking layer. Using 49% HF, the measured roughness is Rq = 10.9 +/- 1.6 nm and with buffered HF (NH4F + HF) the roughness is Rq = 2.4 +/- 0.7 nm. At this level of surface roughness, there is no observable effect on the performance of the devices for this lipoprotein separation.
Collapse
Affiliation(s)
- Bruce H Weiller
- Institute of Microtechnology, University of Neuchâtel, Switzerland
| | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Tsumura M, Kinouchi T, Ono S, Nakajima T, Komoda T. Serum lipid metabolism abnormalities and change in lipoprotein contents in patients with advanced-stage renal disease. Clin Chim Acta 2001; 314:27-37. [PMID: 11718676 DOI: 10.1016/s0009-8981(01)00681-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Arteriosclerosis is the major cause of death in patients with chronic renal failure. There is much interest in the lipid metabolism of patients treated with hemodialysis. METHODS We analyzed low-density lipoproteins (LDL) and high-density lipoproteins (HDL) in chronic renal failure (CRF) patients according to patients on hemodialysis (HD), patients with diabetic nephropathy before initiation of dialysis (DN), and patients with chronic glomerulonephritis in the conservative stage (CGN); and compared the lipid metabolic abnormalities in patients on hemodialysis and those not yet on hemodialysis. We also analyzed the qualitative abnormalities of LDL and HDL and their relationship with the pathological stages. RESULTS Electrophoretic patterns identified small LDL particles and small HDL particles in the three groups, and the degree of denaturation was more enhanced in CRF patients in the conservative stage than in HD patients. For LDL susceptibility to oxidation LDL (oxLDL) by addition of Cu(2+), the lag time was approximately 57 min in healthy controls and CGN patients, but was prolonged to approximately 75 min in HD and DN patients. For HDL susceptibility to oxidation HDL (oxHDL), HD, DN and CGN patients showed lag times shorter than those found in healthy control subjects. These results showed that LDL and HDL in the serum of CRF patients were in a state of enhanced susceptibility to oxidative modification. In Western blot analysis using anti-human-denatured LDL and anti-human-oxidized HDL monoclonal antibodies, bands of low molecular oxLDL at 150-197 kDa were detected in all CRF patients, with marked tailing in CGN patients. Similarly, bands of small oxHDL particles at 110 and 120 kDa were found in HD, DN and CGN patients. CONCLUSIONS Oxidative modification of both LDL and HDL occurs in patients with advanced CRF resulting in small lipoproteins. Increased production of oxLDL and oxHDL is the main cause of lipid metabolic abnormality in CRF patients.
Collapse
Affiliation(s)
- M Tsumura
- R&D Center BML Inc., 1361-1 Matoba, Kawagoe, Saitama 350-1101, Japan.
| | | | | | | | | |
Collapse
|
18
|
Thormann W, Lurie IS, McCord B, Marti U, Cenni B, Malik N. Advances ofcapillary electrophoresis in clinical and forensic analysis (1999-2000). Electrophoresis 2001; 22:4216-43. [PMID: 11824639 DOI: 10.1002/1522-2683(200111)22:19<4216::aid-elps4216>3.0.co;2-w] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this paper, capillary electrophoresis in clinical and forensic analysis is reviewed on the basis of the literature of 1999, 2000 and the first papers in 2001. An overview of progress relevant examples for each major field of application, namely (i) analysis of drug seizures, explosives residues, gunshot residues and inks, (ii) monitoring of drugs, endogenous small molecules and ions in biofluids and tissues, (iii) general screening for serum proteins and analysis of specific proteins (carbohydrate deficient transferrin, alpha1-antitrypsin, lipoproteins and hemoglobins) in biological fluids, and (iv) analysis of nucleic acids and oligonucleotides in biological samples, including oligonucleotide therapeutics, are presented.
Collapse
Affiliation(s)
- W Thormann
- Department of Clinical Pharmacology, University of Bern, Switzerland.
| | | | | | | | | | | |
Collapse
|
19
|
Affiliation(s)
- S N Krylov
- Department of Chemistry, University of Alberta, Edmonton, Canada
| | | |
Collapse
|
20
|
Böttcher A, Schlosser J, Kronenberg F, Dieplinger H, Knipping G, Lackner KJ, Schmitz G. Preparative free-solution isotachophoresis for separation of human plasma lipoproteins: apolipoprotein and lipid composition of HDL subfractions. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)32032-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
21
|
Characterization and quantification of serum lipoprotein subfractions by capillary isotachophoresis: relationships with lipid, apolipoprotein, and lipoprotein levels. J Lipid Res 1999. [DOI: 10.1016/s0022-2275(20)32436-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
22
|
Abstract
This review article with 125 references describes recent developments in capillary zone electrophoresis of proteins. It encompasses approximately the last two years, from the previous review (V. Dolník, Electrophoresis 1997, 18, 2353-2361) through Spring 1999. Topics covered include modeling of the electrophoretic properties of proteins, sample preconcentration and derivatization, wall coatings, improving selectivity, special detection techniques, and applications.
Collapse
Affiliation(s)
- V Dolník
- Molecular Dynamics, Sunnyvale, CA 94086, USA.
| |
Collapse
|