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Racis M, Stanisławska-Sachadyn A, Sobiczewski W, Wirtwein M, Krzemiński M, Krawczyńska N, Limon J, Rynkiewicz A, Gruchała M. Association of Genes Related to Oxidative Stress with the Extent of Coronary Atherosclerosis. Life (Basel) 2020; 10:life10090210. [PMID: 32961879 PMCID: PMC7554836 DOI: 10.3390/life10090210] [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: 08/27/2020] [Revised: 09/14/2020] [Accepted: 09/16/2020] [Indexed: 12/15/2022] Open
Abstract
Oxidative stress is believed to play a critical role in atherosclerosis initiation and progression. In line with this, in a group of 1099 subjects, we determined eight single nucleotide polymorphisms (SNPs) related to oxidative stress (PON1 c.575A>G, MPO c.−463G>A, SOD2 c.47T>C, GCLM c.−590C>T, NOS3 c.894G>T, NOS3 c.−786T>C, CYBA c.214C>T, and CYBA c.−932A>G) and assessed the extent of atherosclerosis in coronary arteries based on Gensini score. An increased risk of having a Gensini score in the higher half of the distribution was observed for the PON1 c.575G allele (odds ratio (OR) = 1.27, 95% confidence interval (CI): 1.004–1.617, p = 0.046). Next, the genetic risk score (GRS) for the additive effect of the total number of pro-oxidative alleles was assessed. We noted an increase in the risk of having a Gensini score above the median with the maximum number of risk alleles (OR = 2.47, 95% CI: 1.19–5.23, p = 0.014). A univariate Spearman’s test revealed significant correlation between the total number of pro-oxidant alleles (GRS) and the Gensini score (ρ = 0.068, p = 0.03). In conclusion, the PON1 c.575A>G variant and the high number of risk alleles (GRS) were independent risk factors for a high Gensini score. We suggest, however, that GRS might occur as a more valuable component in adding a predictive value to the genetic background of atherosclerosis.
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Affiliation(s)
- Milena Racis
- First Department of Cardiology, Medical University of Gdańsk, ul. Dębinki 7, 80-211 Gdańsk, Poland; (W.S.); (M.G.)
- Correspondence: ; Fax: +48-58-3461201
| | - Anna Stanisławska-Sachadyn
- Department of Biology and Genetics, Medical University of Gdańsk, ul. Dębinki 1, 80-211 Gdańsk, Poland; (A.S.-S.); (N.K.); (J.L.)
- Department of Molecular Biotechnology and Microbiology, Gdańsk University of Technology, ul. Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Wojciech Sobiczewski
- First Department of Cardiology, Medical University of Gdańsk, ul. Dębinki 7, 80-211 Gdańsk, Poland; (W.S.); (M.G.)
| | - Marcin Wirtwein
- Department of Pharmacology, Medical University of Gdańsk, ul. Dębinki 7, 80-211 Gdańsk, Poland;
| | - Michał Krzemiński
- Department of Probability and Biomathematics, Gdańsk University of Technology, ul. Narutowicza 11/12, 80-233 Gdańsk, Poland;
| | - Natalia Krawczyńska
- Department of Biology and Genetics, Medical University of Gdańsk, ul. Dębinki 1, 80-211 Gdańsk, Poland; (A.S.-S.); (N.K.); (J.L.)
| | - Janusz Limon
- Department of Biology and Genetics, Medical University of Gdańsk, ul. Dębinki 1, 80-211 Gdańsk, Poland; (A.S.-S.); (N.K.); (J.L.)
| | - Andrzej Rynkiewicz
- Department of Cardiology and Cardiosurgery, University of Warmia and Mazury in Olsztyn, Al. Warszawska 30, 10-082 Olsztyn, Poland;
| | - Marcin Gruchała
- First Department of Cardiology, Medical University of Gdańsk, ul. Dębinki 7, 80-211 Gdańsk, Poland; (W.S.); (M.G.)
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Eryanni-Levin S, Khatib S, Levy-Rosenzvig R, Tamir S, Szuchman-Sapir A. 5,6-δ-DHTL, a stable metabolite of arachidonic acid, is a potential substrate for paraoxonase 1. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:1118-22. [PMID: 25958017 DOI: 10.1016/j.bbalip.2015.04.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/26/2015] [Accepted: 04/30/2015] [Indexed: 01/28/2023]
Abstract
Paraoxonase 1 (PON1) is an antiatherogenic high density lipoprotein-associated lactonase. Recent findings revealed that PON1 knockout mice have low blood pressure, which is negatively correlated with the level of 5,6-epoxyeicosatrienoic acid (5,6-EET), a cytochrome P450 -derived arachidonic acid metabolite. 5,6-EET is an endothelium-derived hyperpolarizing factor that causes arterial dilation. Under physiological conditions, 5,6-EET is unstable, transforming to its δ-lactone (5,6-δ-DHTL) that evades the degradation by soluble epoxide hydrolase (sEH), arguing for the existence of yet another enzyme that is responsible specifically for its hydrolysis. We therefore hypothesized that PON1 degrades the 5,6-δ-DHTL, and this specific PON1 lactonase activity thus decreases endothelial vasodilatation. The aim of the present study was to investigate the PON1-5,6-δ-DHTL relationship. A liquid chromatography mass spectrometry based method for 5,6-EET derivatives identification was developed. Tracking the lactonization of 5,6-EET in a physiological solution revealed that 5,6-EET was fully converted into 5,6-δ-DHTL. Incubation of 5,6-δ-DHTL with rePON1 resulted in 85.1±3.4% degradation of the substrate to 5,6 dihydroxytrienoic acid (5,6-DHET), while only 12.0±8.7% hydrolysis was detected in the absence of PON1. Accordingly, the levels of 5,6-DHTL were found to be significantly higher in the PON1KO mice than in the wild type mice. Kinetic analysis revealed values of Vmax=0.021±0.01μM/s and Km=150.99±62.1μM. Calculation of the docking energy suggested possible interaction of the 5,6-δ-DHTL in the catalytic region of PON1 with free energy of-5.57 Kcal/mol, preferentially for the (S) enantiomer. These findings demonstrate that 5,6-δ-DHTL is a PON1 substrate and imply that the 5,6-EET vasodilation effect may be impaired by PON1.
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Affiliation(s)
- Suzy Eryanni-Levin
- Laboratory of Human Health and Nutrition Sciences, MIGAL-Galilee Research Institute, Ltd., Kiryat Shmona, Israel; Tel-Hai College, Upper Galilee, Israel
| | - Soliman Khatib
- Laboratory of Oxidative Stress and Human Diseases, MIGAL-Galilee Research Institute, Ltd., Kiryat Shmona, Israel; Tel-Hai College, Upper Galilee, Israel
| | - Reut Levy-Rosenzvig
- Laboratory of Human Health and Nutrition Sciences, MIGAL-Galilee Research Institute, Ltd., Kiryat Shmona, Israel; Tel-Hai College, Upper Galilee, Israel
| | - Snait Tamir
- Laboratory of Human Health and Nutrition Sciences, MIGAL-Galilee Research Institute, Ltd., Kiryat Shmona, Israel; Tel-Hai College, Upper Galilee, Israel
| | - Andrea Szuchman-Sapir
- Laboratory of Human Health and Nutrition Sciences, MIGAL-Galilee Research Institute, Ltd., Kiryat Shmona, Israel; Tel-Hai College, Upper Galilee, Israel.
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Dell'Omo G, Penno G, Pucci L, Lucchesi D, Del Prato S, Pedrinelli R. Q192R Paraoxonase (PON)1 Polymorphism, Insulin Sensitivity, and Endothelial Function in Essential Hypertensive Men. CLINICAL MEDICINE INSIGHTS-CARDIOLOGY 2014; 8:57-62. [PMID: 25089090 PMCID: PMC4116359 DOI: 10.4137/cmc.s15493] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 04/30/2014] [Accepted: 05/01/2014] [Indexed: 12/04/2022]
Abstract
AIMS Essential hypertension is characterized by increased reactive oxygen species (ROS) generation harmful for insulin sensitivity and nitric oxide (NO)-mediated vasomotor function, a noxious effect that paraoxonase (PON)1, an antioxidant circulating high-density lipoprotein (HDL)-bound esterase, may counteract. The PON1 gene contains several polymorphisms including a glutamine (Q) to arginine (R) transition at position 192 encoding circulating allozymes with higher antioxidant activity that might influence both parameters. METHODS Q192R was determined by polymerase chain reaction in 72 never-treated, glucose-tolerant, uncomplicated essential hypertensive men. Insulin sensitivity was assessed by homeostasis model assessment (HOMA) and endothelial function by forearm vasodilation (strain-gage venous plethysmography) to intra-arterial acetylcholine (ACH) with sodium nitroprusside (NIP) as a NO-independent control. Additional evaluation variables included 24-hour blood pressure (BP), lipids, BMI, smoking status, and metabolic syndrome (MetS) by Adult Treatment Panel (ATP)-III criteria. R192 was considered as the rare allele, and its associations analyzed by dominant models (Q/Q vs. Q/R + R/R). RESULTS Genotype frequencies were consistent with the Hardy–Weinberg equilibrium. HOMA was lower and insulin resistance (the upper fourth of HOMA values distribution) less prevalent in Q/R + R/R carriers in whom ACH-mediated vasodilatation was greater and endothelial dysfunction (the bottom fourth of ACHAUC values distribution) less frequent than in Q/Q homozygotes. Q192R polymorphism and MetS were unrelated parameters despite their common association with insulin resistance. 24-hour BP, BMI, lipids, and smoking habits were homogeneously distributed across genotypes. CONCLUSIONS Q192R polymorphism associates differentially with insulin sensitivity and endothelial function in essential hypertensive men.
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Affiliation(s)
- Giulia Dell'Omo
- Dipartimenti di Patologia Chirurgica, Medica, Molecolare e dell'Area Critica, Università di Pisa, Pisa, Italy
| | - Giuseppe Penno
- Medicina Clinica e Sperimentale, Università di Pisa, Pisa, Italy
| | - Laura Pucci
- Istituto di Biologia e Biotecnologia Agraria, CNR, Pisa, Italy
| | - Daniela Lucchesi
- Medicina Clinica e Sperimentale, Università di Pisa, Pisa, Italy
| | | | - Roberto Pedrinelli
- Dipartimenti di Patologia Chirurgica, Medica, Molecolare e dell'Area Critica, Università di Pisa, Pisa, Italy
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Paraoxonase1 deficiency in mice is associated with hypotension and increased levels of 5,6-epoxyeicosatrienoic acid. Atherosclerosis 2012; 222:92-8. [DOI: 10.1016/j.atherosclerosis.2012.01.047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/10/2012] [Accepted: 01/28/2012] [Indexed: 01/11/2023]
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Abstract
OBJECTIVES Paraoxonase is a high-density lipoprotein-bound antioxidant enzyme that inhibits atherosclerosis and endothelial dysfunction. Coronary collateral flow is a crucial clinical entity with significant impact on the cardiovascular morbidity and mortality. This study sought to determine the relationship between the degree of angiographically visible coronary collateral circulation and serum paraoxonase activity. METHODS The study population included 98 patients (mean age=57.9+/-10.1 years, 65 men) with angiographically documented total occlusion in one of the major coronary arteries. Development of collaterals was classified by Rentrop's method. Patients were defined as having poorly developed collaterals for Rentrop grades 0 and 1 or well-developed collaterals for Rentrop grades 2 and 3. Serum paraoxonase and arylesterase activities were measured spectrophotometrically. RESULTS Statistically significant differences between well and poorly developed collateral groups in respect to serum low-density lipoprotein cholesterol level (P=0.046), and serum paraoxonase (P=0.001), and arylesterase (P=0.014) activities were present. Serum low-density lipoprotein cholesterol level (chi=4.15, beta=-0.347, P=0.032) and serum paraoxonase activity (chi=10.43, beta=0.008, P=0.022) were independent predictors of well-developed coronary collateral flow. Serum paraoxonase activity gradually increased from collateral grade 0 to collateral grade 3 (analysis of variance P=0.003). Serum paraoxonase (r=0.362 and P<0.001) and arylesterase (r=0.245 and P=0.015) activities were both correlated with collateral flow grade. CONCLUSION Findings of this study suggest that serum paraoxonase activity is independently associated with the degree of coronary collateral flow and reduced serum paraoxonase activity might represent a biochemical marker of impaired coronary collateral flow.
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Yildiz A, Gur M, Yilmaz R, Demirbag R, Polat M, Selek S, Celik H, Erel O. Association of paraoxonase activity and coronary blood flow. Atherosclerosis 2008; 197:257-63. [PMID: 17537444 DOI: 10.1016/j.atherosclerosis.2007.04.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 03/25/2007] [Accepted: 04/03/2007] [Indexed: 01/30/2023]
Abstract
BACKGROUND Paraoxonase (PON) is a high-density lipoprotein-bound anti-oxidant enzyme that inhibits atherosclerosis and endothelial dysfunction. Slow coronary flow (SCF) has long been identified and endothelial dysfunction and atherosclerosis of epicardial coronary arteries and microvasculature were reported to be associated with SCF. Consequently, we aimed to investigate the association between coronary blood flow by means of Thrombolysis in Myocardial Infarction frame count (TFC) and serum PON activity and other laboratory parameters in patients with SCF compared to control cases. METHODS Twenty-four patients with SCF and 110 control cases with normal coronary flow were studied after quantifying coronary blood flow according to TFC. Serum PON activity was evaluated by measuring the rate of paraoxon hydrolysis. The association between TFC and serum PON activity and other clinical and laboratory parameters were evaluated. RESULTS There were statistically significant differences between SCF and control groups in respect to serum uric acid (p=0.001), high sensitive C-reactive protein (p=0.03) levels and serum PON activity (p<0.001). The mean TFC was correlated with male gender (r=0.263, p=0.002), serum uric acid level (r=0.287, p=0.001), hemoglobin concentration (r=0.192, p=0.032) and serum PON activity (r=-0.306, p<0.001). Serum uric acid level (chi(2)=10.08, beta=0.362, p=0.009) and serum PON activity (chi(2)=16.73, beta=-0.005, p=0.001) were independent predictors of SCF whereas the only independent predictor of mean TFC was serum PON activity (beta=-0.318, p<0.001). CONCLUSION These findings suggest that serum PON activity is independently associated with mean TFC and reduced serum PON activity might represent a biochemical marker of SCF.
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Affiliation(s)
- Ali Yildiz
- Harran University, School of Medicine, Department of Cardiology, Sanliurfa, Turkey.
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Marra M, Marchegiani F, Antonicelli R, Sirolla C, Spazzafumo L, Olivieri F, Franceschi C, Testa R, Paolisso G, James RW, Boemi M, Parati G. The PON1192RR genotype is associated with a higher prevalence of arterial hypertension. J Hypertens 2006; 24:1293-8. [PMID: 16794478 DOI: 10.1097/01.hjh.0000234109.46486.9b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate whether genetic polymorphism of paraoxonase (PON1192), an enzyme which protects low density lipoprotein from oxidation, is related to the prevalence of arterial hypertension. METHODS Two groups of carefully selected subjects of both sexes were enrolled and compared. The first group comprised 219 healthy controls (mean age 46.5 +/- 14.7 years) whereas the second comprised 119 hypertensive patients (mean age 47.9 +/- 10.5 years) with untreated essential arterial hypertension. Anthropometric and biochemical parameters were within the normal range in both groups. The PON1192 polymorphism was determined by a polymerase chain reaction-restriction fragment length polymorphism approach. RESULTS In hypertensive patients, a significant increase of the frequency of PON1192RR genotype with respect to healthy controls (14.3 versus 5.0%, P = 0.003) was found. Logistic regression analyses also showed that the PON1192RR genotype was independently associated with a four-fold increase in susceptibility to arterial hypertension (odds ratio = 4.31; 95% confidence interval = 1.63-11.43, P = 0.003). CONCLUSIONS The finding that PON1192RR genotype is associated with a higher prevalence of arterial hypertension may contribute to improving the stratification of cardiovascular risk within a population aged 30-60 years. Determination of the PON1192 polymorphism may help to identify those individuals who are prone to developing cardiovascular diseases at an early stage, suggesting the need for close monitoring of cardiovascular risk factors before the onset of cardiovascular disease.
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Colacurci N, Chiàntera A, Fornaro F, de Novellis V, Manzella D, Arciello A, Chiàntera V, Improta L, Paolisso G. Effects of soy isoflavones on endothelial function in healthy postmenopausal women. Menopause 2005; 12:299-307. [PMID: 15879919 DOI: 10.1097/01.gme.0000147017.23173.5b] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To evaluate the effects of soy isoflavone administration on endothelial function in healthy postmenopausal women. DESIGN Sixty naturally postmenopausal women were randomly assigned to receive isoflavone or placebo tablets for 6 months. Endothelium-dependent vasodilatation was measured by brachial reactivity technique along with levels of plasma soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, P-selectin and soluble thrombomodulin, von Willebrand factor, and tissue plasminogen activator. Differences between endothelium-dependent and endothelium-independent vasodilatation were assessed by evaluating brachial reactivity parameters after reactive hyperemia and after sublingual administration of nitroglycerin; furthermore, in the active group, the effect of isoflavones was also evaluated during the intra-arterial infusion of N-monomethyl-L-arginine. Serum levels of lipids [high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides and lipoprotein(a)] and hemostatic factors (prothrombin, fibrinogen, plasminogen activator inhibitor-1, and fibrin D-dimer) were also measured. To confirm the absorption of isoflavones, their blood concentrations were determined. RESULTS Isoflavone treatment versus placebo was associated with a significant improvement in endothelium-dependent vasodilatation but had no impact on endothelial-independent arterial diameter and flow. Intra-arterial infusion of N-monomethyl-L-arginine inhibited the significant effect of isoflavones on endothelium-mediated vasodilatation. Furthermore, isoflavone group experienced statistically significant reductions in plasma concentrations of ICAM-1, VCAM-1, and E-selectin. Levels of soluble thrombomodulin, von Willebrand factor, tissue plasminogen activator, lipids, and hemostatic factors did not change significantly throughout the study in both groups. CONCLUSIONS Our findings suggest a positive influence of soy isoflavones on endothelial function in healthy postmenopausal women as evidenced by an improvement in endothelium-dependent vasodilatation and a reduction in plasma adhesion molecule levels.
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Affiliation(s)
- Nicola Colacurci
- Department of Gynecology and Obstetrics, IV Internal Medicine, School of Medicine, Second University of Naples, Naples, Italy.
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Manzella D, Grella R, Abbatecola AM, Paolisso G. Repaglinide administration improves brachial reactivity in type 2 diabetic patients. Diabetes Care 2005; 28:366-71. [PMID: 15677794 DOI: 10.2337/diacare.28.2.366] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Several studies have demonstrated that endothelial dysfunction plays a central role in diabetic mortality and that the prooxidative effect of postprandial hyperglycemia may actively contribute to atherogenesis. Thus, we investigated the possible effect of short-acting (repaglinide) and long-acting (glibenclamide) insulin secretagogues on endothelial function in type 2 diabetic patients. RESEARCH DESIGN AND METHODS Sixteen type 2 diabetic patients undergoing diet treatment and with poor glucose control volunteered for the study. The study was designed as a 4-month, randomized, cross-over, parallel-group trial of repaglinide (1 mg twice a day) versus glibenclamide (5 mg twice a day). All patients underwent the following investigations: 1) anthropometrics determinations, 2) blood sampling for routine laboratory analyses and for assessment of oxidative stress indexes, and 3) a brachial reactivity test to evaluate the endothelial function through the study of arterial diameter and flow changes with and without intraarterial infusion of N(G)-monomethyl-l-arginine, an inhibitor of nitric oxide synthase and tetraethylammonium chloride (TEA), a Ca(2+)-activated K(+) (K(Ca)) channel blocker. All patients were randomly assigned to receive repaglinide or glibenclamide for a period of 4 weeks. RESULTS Repaglinide administration was associated with a significant reduction in 2-h plasma glucose levels (P < 0.001) and in plasma thiobarbituric acid-reactive substances (TBARS) concentrations (P < 0.001) and with a significant increase in plasma antioxidant power, assessed as Trolox equivalent antioxidant capacity (TEAC) (P < 0.001), effects not observed after glibenclamide administration. With regard to brachial reactivity parameters, repaglinide but not glibenclamide was associated with a significant improvement in brachial reactivity parameters (P < 0.003 for all parameters). In contrast, intra-arterial infusion of L-NMMA and TEA reduced the beneficial effect of repaglinide. CONCLUSIONS Repaglinide administration, through good control of postprandial glucose levels, improves brachial reactivity and declines oxidative stress indexes.
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Affiliation(s)
- Daniela Manzella
- Department of Geriatric Medicine and Metabolic Diseases VI, Internal Medicine, Piazza Miraglia 2 I-80138, Napoli, Italy
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Bonafè M, Marchegiani F, Cardelli M, Olivieri F, Cavallone L, Giovagnetti S, Pieri C, Marra M, Antonicelli R, Troiano L, Gueresi P, Passeri G, Berardelli M, Paolisso G, Barbieri M, Tesei S, Lisa R, De Benedictis G, Franceschi C. Genetic analysis of Paraoxonase (PON1) locus reveals an increased frequency of Arg192 allele in centenarians. Eur J Hum Genet 2002; 10:292-6. [PMID: 12082503 DOI: 10.1038/sj.ejhg.5200806] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2001] [Revised: 03/08/2002] [Accepted: 03/20/2002] [Indexed: 11/09/2022] Open
Abstract
Human Paraoxonase (PON1) is a High-Density Lipoprotein (HDL)-associated esterase that hydrolyses lipo-peroxides. PON1 has recently attracted attention as a protective factor against oxidative modification of LDL and may therefore play an important role in the prevention of the atherosclerotic process. Two polymorphisms have been extensively studied: a Leucine (L allele) to Methionine (M allele) substitution at codon 55, and a Glutamine (A allele) to Arginine (B allele) substitution at codon 192. We have examined these two aminoacidic changes in 579 people aged 20 to 65 years old, and 308 centenarians. We found that the percentage of carriers of the B allele at codon 192 (B+ individuals) is higher in centenarians than in controls (0.539 vs 0.447), moreover we found that among the B+ individuals, the phenomenon was due to an increase of people carrying M alleles at codon 55 locus. In conclusion, we propose that genetic variability at PON1 locus affects survival at extreme advanced age.
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Abstract
Studies using both in vitro and in vivo techniques have repeatedly shown that endothelium-dependent vasodilation (EDV) is impaired in different forms of experimental as well as human hypercholesterolemia. Clearly this impaired EDV can be reversed by lowering cholesterol levels by diet or medical therapy. Competitive blocking of L-arginine, changes in nitric oxide synthase activity, increased release of endothelin-1, and inactivation of nitric oxide due to superoxide ions all contribute to the impairment in EDV during dyslipidemia. The oxidation of low density lipoprotein, with its compound lysophosphatidylcholine, plays a critical role in these events. However, data on the role of triglycerides and fat-rich meals regarding EDV are not so consistent as data for cholesterol, although a view that the compositions of individual fatty acids and antioxidants are of major importance is emerging. Thus, this review shows that while impaired EDV is a general feature of hypercholesterolemia, the mechanisms involved and the therapeutic opportunities available still have to be investigated. Furthermore, discrepancies regarding the role of triglycerides and fat content in food may be explained by divergent effects of different fatty acids on the endothelium.
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Affiliation(s)
- Lars Lind
- Department of Medicine, Uppsala University Hospital and AstraZeneca R&D, Möndal, Sweden.
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