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PO3-72 QUANTITATION OF GLYCATION ADDUCTS IN HDL BY LIQUID CHROMATOGRAPHY WITH TANDEM MASS SPECTROMETRIC DETECTION
Poster Sessions PO3 Pathophysiology of lipids and lipoproteins lipoproteins (p<0,01), which is probably due to activation of the compensatory mechanisms aimed at normalization of the impaired metabolism. The data obtained revealing that small-size IC prevail in strokes proves the autoantigenicity of atherogenic lipoproteins and testifies that VLDL are the main IC antigens in strokes of atherosclerotic etiology, which can also be proved by the statistically valid correlation between the levels of small-size IC, triglycerides and VLDL in strokes (r = 0,62; r = 0,61) and in transient ischemic attacks (r = 0,71 and r = 0,64) revealed by our study. PO3-69
LP(A) AND APO(A) PHENOTYPE AND WITH PATENCY OF VEIN GRAFT IN PATIENTS AFTER CABG
L.N. Il’yina, O.I. Afanasieva, M.V. Ezhov, M.I. Afanasieva, V.E. Sinitsyn, R.S. Akchurin, S.N. Pokrovsky. Cardiology Research Center, Moscow, Russia
PO3-70
REDUCED APO C-III AND APO E CONCENTRATIONS BUT PARADOXICAL INCREASE OF APO C-III/APO E RATIO IN E4 INDIVIDUALS. A LINK WITH METABOLIC SYNDROME
N. Martinelli 1 , A. Bassi 2 , E. Trabetti 3 , D. Girelli 1 , F. Pizzolo 1 , S. Friso 1 , P.F. Pignatti 3 , R. Corrocher 1 , O. Olivieri 1 . 1 Department of Clinical and Experimental Medicine, University of Verona, Verona, Italy; 2 Institute of Clinical Chemistry, University of Verona, Verona, Italy; 3 Section of Biology and Genetics, Department of Mother and Child Biology-Genetics, University of Verona, Verona, Italy Background and Aims: Triglyceride-rich lipoproteins contain both apolipoproteins E (ApoE) and C-III. (ApoC-III) that show opposite functional properties. ApoC-III/ApoE ratio should therefore more strictly reflect atherogenic/anti-atherogenic balance than the single apolipoprotein. The relationships between APOE (ε2/ε3/ε4) gene polymorphism and ApoC-III/ApoE ratio has never been investigated. Methods: A large population (n=552) of cardiovascular patients, without diabetes and/or lipid-lowering therapy, was genotyped for ε2/ε3/ε4 polymorphism and their ApoC-III/ApoE ratio evaluated. A second group of patients (n=76) affected by peripheral artery disease was also genotyped and ApoC-III/ApoE ratio was measured in HDL and non-HDL fractions. Results: Subjects with E2 had higher and E4 carriers lower TG, ApoE and ApoC-III levels, respectively. ApoC-III/ApoE ratio showed an opposite trend, gradually increasing from E2/E2 to E4/E4 subjects. When the population was subdivided between subjects with (n=100) or without (n=452) metabolic syndrome (MetSyn), E4 carriers were more frequent in MetSyn group (OR 2.08 with a 95%CI 1.22-3.5). MetSyn patients had elevated ApoC-III/ApoE ratio and subjects presenting an increasing number of MetSyn components also had higher ratio values. The distribution of ApoC-III/ApoE ratio was confirmed also in the second group, with lower values in E2/E3 and higher in E3/E4 subjects. Similar results were obtained for the concentrations measured in non-HDL fractions, but not in the HDL fractions. Conclusions: APOE ε2/ε3/ε4 gene polymorphism is a determinant of the relative proportion of apolipoprotein C-III to E. Carriers of unfavourable
E4 allele present the highest ApoC-III/ApoE ratio and are twofold more frequent among individuals affected by MetSyn than in normal population. PO3-71
LIPOPROTEIN(A) AND APO(A) PHENOTYPES ARE ASSOCIATED WITH CAROTID ATHEROSCLEROSIS IN YOUNGER CORONARY HEART DISEASE PATIENTS
O.I. Afanasieva, M.V. Ezhov, A.A. Lyakishev, M.I. Afanasieva, V.V. Kukharchuk, S.N. Pokrovsky. Cardiology Research Center, Moscow, Russia The aim of the study was to assess a relation of Lp(a) and apo(a) phenotypes to carotid atherosclerosis in patients with established CHD. Methods: We have included 168 male patients (mean age 52.8±7.7 years) with CHD proven by angiography. High-resolution duplex ultrasound was used to evaluate the carotid arteries. Lipids, Lp(a) concentrations and apo(a) phenotypes were determined in the patients blood serum. Results: Signs of carotid atherosclerosis (intima-media thickening, n=27, stenosis<50%, n=100, stenosis>50%, n=17) was revealed in 86% of CHD patients. Lp(a), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), age and low-molecular weight (LMW) apo(a) phenotypes correlated with severity of carotid lesions. After adjusting for age and Lp(a)-cholesterol, TC and LDL-C lost their significant association with carotid lesions. Lp(a) levels and frequency LMW of apo(a) phenotypes were higher in group with carotid plaques than in plaques-free group. This difference was expressed only in patients younger than 55 years old, but not the older ones.
Conclusion: Elevated Lp(a) level and low-molecular weight apo(a) phenotypes are associated with presence and severity of carotid atherosclerotic plaques in CHD male patients. This association is stronger in the group of younger patients. PO3-72
QUANTITATION OF GLYCATION ADDUCTS IN HDL BY LIQUID CHROMATOGRAPHY WITH TANDEM MASS SPECTROMETRIC DETECTION
N. Rabbani, P.J. Thornalley. Department of Biological Sciences, University of Essex, Colchester, UK Background and Aims: Glycation changes the structure and impairs the function of HDL in vivo. The “gold standard” assay method for glycation adducts is liquid chromatography with tandem mass spectrometric detection (LC-MS/MS). We report herein the quantitation of the early glycation adduct Nε-fructosyl-lysine (FL) and the advanced glycation endproduct (AGE) Nε-carboxymethyl-lysine (CML) residue content of apolipoprotein A in HDL of patients with type 2 diabetes and normal healthy controls. Methods: Diabetic patients were recruited from those attending the Diabetes Clinic at Colchester General Hospital, Colchester, U.K. Subject characteristics were: age (years) – controls 42 ± 5 (n = 6), diabetics 53 ± 5 (n = 8, P<0.01); glycated haemoglobin (%) - controls 4.88 ± 0.14, diabetics 9.91 ± 2.77 (P<0.001); and HDL cholesterol (mM) – controls 1.40 ± 0.20, diabetics 1.21 ± 0.33. HDL was purified from peripheral venous plasma by density gradient centrifugation and purity confirmed by SDS-PAGE. It was delipidated and hydrolysed by exhaustive enzymatic hydrolysis. FL and CML residue content were determined by LC-MS/MS with internal standardisation by stable isotope substituted standards. Results: The FL residue content of HDL (mmol/mol lys) was: controls 4.7 ± 0.7 and diabetics 12.5 ± 3.7 (P<0.001). The CML residue content of HDL (mmol/mol lys) was: controls 0.0053 ± 0.0025 and diabetics 0.0169 ± 0.0128 (P<0.05). Conclusions: The percentage early glycation (FL) of HDL in control subjects was 10% and increased to 26% in diabetes. The percentage of AGE (CML) of HDL was 0.01% in control subjects and increased 0.03% in diabetes.
76th Congress of the European Atherosclerosis Society, June 10–13, 2007, Helsinki, Finland
POSTER SESSIONS
Aim of the study was to investigate the correlation of the Lp(a) concentration and low-molecular weight phenotype (LMW) apo(a) and the clinical status of CHD in the patients after coronary artery bypass grafting (CABG). Methods: 68 patients – men age 36 - 69 years (mean 53±8) during first year after CABG were tested. Graft patency was examined by electron beam computerized tomography. The determination of Lp(a), serum lipids, apoB and apoAI levels and phenotyping of apo(a) were performed. Results: Patients were divided into two groups in accordance with their graft status: 44 (65%) with one or more occlusions and 24 (35%) without occlusions. There were no significant differences between the groups concerning age, CHD family history, hypertension, serum lipids and apoB. Lp(a) level was higher in group with occlusions 43±42 mg/dl (median 23 mg/dl), than group without the occlusions of 29±35 mg/dl (median 15 mg/dl). LMW apo(a) phenotype was found twice as frequently for patients with angina pectories during the first year after operation than patients without its (58% vs 28% p<0.05). In the group with the occlusions LMW apo(a) phenotype was found in 45% cases, whereas without the occlusions in 34%. Conclusion: The increased concentration Lp(a) and LMW phenotype apo(a) correlate with occlusions of bypass vien graft and chest paint during first year after the CABG.
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LP(A) AND APO(A) PHENOTYPE AND WITH PATENCY OF VEIN GRAFT IN PATIENTS AFTER CABG
L.N. Il’yina, O.I. Afanasieva, M.V. Ezhov, M.I. Afanasieva, V.E. Sinitsyn, R.S. Akchurin, S.N. Pokrovsky. Cardiology Research Center, Moscow, Russia
PO3-70
REDUCED APO C-III AND APO E CONCENTRATIONS BUT PARADOXICAL INCREASE OF APO C-III/APO E RATIO IN E4 INDIVIDUALS. A LINK WITH METABOLIC SYNDROME
N. Martinelli 1 , A. Bassi 2 , E. Trabetti 3 , D. Girelli 1 , F. Pizzolo 1 , S. Friso 1 , P.F. Pignatti 3 , R. Corrocher 1 , O. Olivieri 1 . 1 Department of Clinical and Experimental Medicine, University of Verona, Verona, Italy; 2 Institute of Clinical Chemistry, University of Verona, Verona, Italy; 3 Section of Biology and Genetics, Department of Mother and Child Biology-Genetics, University of Verona, Verona, Italy Background and Aims: Triglyceride-rich lipoproteins contain both apolipoproteins E (ApoE) and C-III. (ApoC-III) that show opposite functional properties. ApoC-III/ApoE ratio should therefore more strictly reflect atherogenic/anti-atherogenic balance than the single apolipoprotein. The relationships between APOE (ε2/ε3/ε4) gene polymorphism and ApoC-III/ApoE ratio has never been investigated. Methods: A large population (n=552) of cardiovascular patients, without diabetes and/or lipid-lowering therapy, was genotyped for ε2/ε3/ε4 polymorphism and their ApoC-III/ApoE ratio evaluated. A second group of patients (n=76) affected by peripheral artery disease was also genotyped and ApoC-III/ApoE ratio was measured in HDL and non-HDL fractions. Results: Subjects with E2 had higher and E4 carriers lower TG, ApoE and ApoC-III levels, respectively. ApoC-III/ApoE ratio showed an opposite trend, gradually increasing from E2/E2 to E4/E4 subjects. When the population was subdivided between subjects with (n=100) or without (n=452) metabolic syndrome (MetSyn), E4 carriers were more frequent in MetSyn group (OR 2.08 with a 95%CI 1.22-3.5). MetSyn patients had elevated ApoC-III/ApoE ratio and subjects presenting an increasing number of MetSyn components also had higher ratio values. The distribution of ApoC-III/ApoE ratio was confirmed also in the second group, with lower values in E2/E3 and higher in E3/E4 subjects. Similar results were obtained for the concentrations measured in non-HDL fractions, but not in the HDL fractions. Conclusions: APOE ε2/ε3/ε4 gene polymorphism is a determinant of the relative proportion of apolipoprotein C-III to E. Carriers of unfavourable
E4 allele present the highest ApoC-III/ApoE ratio and are twofold more frequent among individuals affected by MetSyn than in normal population. PO3-71
LIPOPROTEIN(A) AND APO(A) PHENOTYPES ARE ASSOCIATED WITH CAROTID ATHEROSCLEROSIS IN YOUNGER CORONARY HEART DISEASE PATIENTS
O.I. Afanasieva, M.V. Ezhov, A.A. Lyakishev, M.I. Afanasieva, V.V. Kukharchuk, S.N. Pokrovsky. Cardiology Research Center, Moscow, Russia The aim of the study was to assess a relation of Lp(a) and apo(a) phenotypes to carotid atherosclerosis in patients with established CHD. Methods: We have included 168 male patients (mean age 52.8±7.7 years) with CHD proven by angiography. High-resolution duplex ultrasound was used to evaluate the carotid arteries. Lipids, Lp(a) concentrations and apo(a) phenotypes were determined in the patients blood serum. Results: Signs of carotid atherosclerosis (intima-media thickening, n=27, stenosis<50%, n=100, stenosis>50%, n=17) was revealed in 86% of CHD patients. Lp(a), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), age and low-molecular weight (LMW) apo(a) phenotypes correlated with severity of carotid lesions. After adjusting for age and Lp(a)-cholesterol, TC and LDL-C lost their significant association with carotid lesions. Lp(a) levels and frequency LMW of apo(a) phenotypes were higher in group with carotid plaques than in plaques-free group. This difference was expressed only in patients younger than 55 years old, but not the older ones.
Conclusion: Elevated Lp(a) level and low-molecular weight apo(a) phenotypes are associated with presence and severity of carotid atherosclerotic plaques in CHD male patients. This association is stronger in the group of younger patients. PO3-72
QUANTITATION OF GLYCATION ADDUCTS IN HDL BY LIQUID CHROMATOGRAPHY WITH TANDEM MASS SPECTROMETRIC DETECTION
N. Rabbani, P.J. Thornalley. Department of Biological Sciences, University of Essex, Colchester, UK Background and Aims: Glycation changes the structure and impairs the function of HDL in vivo. The “gold standard” assay method for glycation adducts is liquid chromatography with tandem mass spectrometric detection (LC-MS/MS). We report herein the quantitation of the early glycation adduct Nε-fructosyl-lysine (FL) and the advanced glycation endproduct (AGE) Nε-carboxymethyl-lysine (CML) residue content of apolipoprotein A in HDL of patients with type 2 diabetes and normal healthy controls. Methods: Diabetic patients were recruited from those attending the Diabetes Clinic at Colchester General Hospital, Colchester, U.K. Subject characteristics were: age (years) – controls 42 ± 5 (n = 6), diabetics 53 ± 5 (n = 8, P<0.01); glycated haemoglobin (%) - controls 4.88 ± 0.14, diabetics 9.91 ± 2.77 (P<0.001); and HDL cholesterol (mM) – controls 1.40 ± 0.20, diabetics 1.21 ± 0.33. HDL was purified from peripheral venous plasma by density gradient centrifugation and purity confirmed by SDS-PAGE. It was delipidated and hydrolysed by exhaustive enzymatic hydrolysis. FL and CML residue content were determined by LC-MS/MS with internal standardisation by stable isotope substituted standards. Results: The FL residue content of HDL (mmol/mol lys) was: controls 4.7 ± 0.7 and diabetics 12.5 ± 3.7 (P<0.001). The CML residue content of HDL (mmol/mol lys) was: controls 0.0053 ± 0.0025 and diabetics 0.0169 ± 0.0128 (P<0.05). Conclusions: The percentage early glycation (FL) of HDL in control subjects was 10% and increased to 26% in diabetes. The percentage of AGE (CML) of HDL was 0.01% in control subjects and increased 0.03% in diabetes.
76th Congress of the European Atherosclerosis Society, June 10–13, 2007, Helsinki, Finland
POSTER SESSIONS
Aim of the study was to investigate the correlation of the Lp(a) concentration and low-molecular weight phenotype (LMW) apo(a) and the clinical status of CHD in the patients after coronary artery bypass grafting (CABG). Methods: 68 patients – men age 36 - 69 years (mean 53±8) during first year after CABG were tested. Graft patency was examined by electron beam computerized tomography. The determination of Lp(a), serum lipids, apoB and apoAI levels and phenotyping of apo(a) were performed. Results: Patients were divided into two groups in accordance with their graft status: 44 (65%) with one or more occlusions and 24 (35%) without occlusions. There were no significant differences between the groups concerning age, CHD family history, hypertension, serum lipids and apoB. Lp(a) level was higher in group with occlusions 43±42 mg/dl (median 23 mg/dl), than group without the occlusions of 29±35 mg/dl (median 15 mg/dl). LMW apo(a) phenotype was found twice as frequently for patients with angina pectories during the first year after operation than patients without its (58% vs 28% p<0.05). In the group with the occlusions LMW apo(a) phenotype was found in 45% cases, whereas without the occlusions in 34%. Conclusion: The increased concentration Lp(a) and LMW phenotype apo(a) correlate with occlusions of bypass vien graft and chest paint during first year after the CABG.
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