1
|
Mahrooz A. Pleiotropic functions and clinical importance of circulating HDL-PON1 complex. Adv Clin Chem 2024; 121:132-171. [PMID: 38797541 DOI: 10.1016/bs.acc.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
High density lipoprotein (HDL) functions are mostly mediated through a complex proteome, particularly its enzymes. HDL can provide a scaffold for the assembly of several proteins that affect each other's function. HDL particles, particularly small, dense HDL3, are rich in paraoxonase 1 (PON1), which is an important enzyme in the functionality of HDL, so the antioxidant and antiatherogenic properties of HDL are largely attributed to this enzyme. There is an increasing need to represent a valid, reproducible, and reliable method to assay HDL function in routine clinical laboratories. In this context, HDL-associated proteins may be key players; notably PON1 activity (its arylesterase activity) may be a proper candidate because its decreased activity can be considered an important risk factor for HDL dysfunctionality. Of note, automated methods have been developed for the measurement of serum PON1 activity that facilitates its assay in large sample numbers. Arylesterase activity is proposed as a preferred activity among the different activities of PON1 for its assay in epidemiological studies. The binding of PON1 to HDL is critical for the maintenance of its activity and it appears apolipoprotein A-I plays an important role in HDL-PON1 interaction as well as in the biochemical and enzymatic properties of PON1. The interrelationships between HDL, PON1, and HDL's other components are complex and incompletely understood. The purpose of this review is to discuss biochemical and clinical evidence considering the interactions of PON1 with HDL and the role of this enzyme as an appropriate biomarker for HDL function as well as a potential therapeutic target.
Collapse
Affiliation(s)
- Abdolkarim Mahrooz
- Immunogenetics Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran; Department of Clinical Biochemistry and Medical Genetics, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
| |
Collapse
|
2
|
Denimal D. Antioxidant and Anti-Inflammatory Functions of High-Density Lipoprotein in Type 1 and Type 2 Diabetes. Antioxidants (Basel) 2023; 13:57. [PMID: 38247481 PMCID: PMC10812436 DOI: 10.3390/antiox13010057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/24/2023] [Accepted: 12/27/2023] [Indexed: 01/23/2024] Open
Abstract
(1) Background: high-density lipoproteins (HDLs) exhibit antioxidant and anti-inflammatory properties that play an important role in preventing the development of atherosclerotic lesions and possibly also diabetes. In turn, both type 1 diabetes (T1D) and type 2 diabetes (T2D) are susceptible to having deleterious effects on these HDL functions. The objectives of the present review are to expound upon the antioxidant and anti-inflammatory functions of HDLs in both diabetes in the setting of atherosclerotic cardiovascular diseases and discuss the contributions of these HDL functions to the onset of diabetes. (2) Methods: this narrative review is based on the literature available from the PubMed database. (3) Results: several antioxidant functions of HDLs, such as paraoxonase-1 activity, are compromised in T2D, thereby facilitating the pro-atherogenic effects of oxidized low-density lipoproteins. In addition, HDLs exhibit diminished ability to inhibit pro-inflammatory pathways in the vessels of individuals with T2D. Although the literature is less extensive, recent evidence suggests defective antiatherogenic properties of HDL particles in T1D. Lastly, substantial evidence indicates that HDLs play a role in the onset of diabetes by modulating glucose metabolism. (4) Conclusions and perspectives: impaired HDL antioxidant and anti-inflammatory functions present intriguing targets for mitigating cardiovascular risk in individuals with diabetes. Further investigations are needed to clarify the influence of glycaemic control and nephropathy on HDL functionality in patients with T1D. Furthermore, exploring the effects on HDL functionality of novel antidiabetic drugs used in the management of T2D may provide intriguing insights for future research.
Collapse
Affiliation(s)
- Damien Denimal
- Unit 1231, Center for Translational and Molecular Medicine, University of Burgundy, 21000 Dijon, France;
- Department of Clinical Biochemistry, Dijon Bourgogne University Hospital, 21079 Dijon, France
| |
Collapse
|
3
|
Interaction between Apo A-II -265T > C polymorphism and dietary total antioxidant capacity on some oxidative stress and inflammatory markers in patients with type 2 diabetes mellitus. Br J Nutr 2022; 128:13-29. [PMID: 34372957 DOI: 10.1017/s0007114521002993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This work aims to examine the interaction between apo A2 (Apo A-II) -265T > C SNP and dietary total antioxidant capacity (DTAC) on inflammation and oxidative stress in patients with type 2 diabetes mellitus. The present cross-sectional study included 180 patients (35-65 years) with identified Apo A-II genotype. Dietary intakes were assessed by a FFQ. DTAC was computed using the international databases. IL-18 (IL18), high-sensitivity C-reactive protein (hs-CRP), pentraxin (PTX3), serum total antioxidant capacity (TAC), superoxide dismutase (SOD) activity and 8-isoprostaneF2α (PGF2α) markers were obtained according to standard protocols. General linear model was used to evaluate the interaction. The interaction of gene and DTAC (PFRAP = 0·039 and PORAC = 0·042) on PGF2α level was significant after adjusting for confounders. A significant interaction was observed on IL18 level (PORAC = 0·018 and PFRAP = 0·048) and SOD (PTEAC = 0·037) in obese patients. Among patients whose DTAC was higher than the median intake, the levels of hs-CRP and PGF2α were significantly higher only in individuals with CC genotype. Serum TAC (PFRAP = 0·030, PORAC = 0·049) and SOD were significantly lower in the CC genotype. There was a favourable relationship between the high-DTAC and SOD (obese: PTEAC = 0·034, non-obese: PFRAP = 0·001, PTRAP < 0·0001, PTEAC = 0·003 and PORAC = 0·001) and PGF2α (non-obese: PORAC = 0·024) in T-allele carriers. The rs5082 SNP interacts with DTAC to influence several cardiometabolic risk factors. Also, we found dietary recommendations for antioxidant-rich foods intake might be useful in the prevention of diabetes complications in the T carrier more effectively than the CC genotype. Future large studies are required to confirm these results.
Collapse
|
4
|
Apolipoprotein A-II, a Player in Multiple Processes and Diseases. Biomedicines 2022; 10:biomedicines10071578. [PMID: 35884883 PMCID: PMC9313276 DOI: 10.3390/biomedicines10071578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/21/2022] [Accepted: 06/28/2022] [Indexed: 11/26/2022] Open
Abstract
Apolipoprotein A-II (apoA-II) is the second most abundant apolipoprotein in high-density lipoprotein (HDL) particles, playing an important role in lipid metabolism. Human and murine apoA-II proteins have dissimilar properties, partially because human apoA-II is dimeric whereas the murine homolog is a monomer, suggesting that the role of apoA-II may be quite different in humans and mice. As a component of HDL, apoA-II influences lipid metabolism, being directly or indirectly involved in vascular diseases. Clinical and epidemiological studies resulted in conflicting findings regarding the proatherogenic or atheroprotective role of apoA-II. Human apoA-II deficiency has little influence on lipoprotein levels with no obvious clinical consequences, while murine apoA-II deficiency causes HDL deficit in mice. In humans, an increased plasma apoA-II concentration causes hypertriglyceridemia and lowers HDL levels. This dyslipidemia leads to glucose intolerance, and the ensuing high blood glucose enhances apoA-II transcription, generating a vicious circle that may cause type 2 diabetes (T2D). ApoA-II is also used as a biomarker in various diseases, such as pancreatic cancer. Herein, we provide a review of the most recent findings regarding the roles of apoA-II and its functions in various physiological processes and disease states, such as cardiovascular disease, cancer, amyloidosis, hepatitis, insulin resistance, obesity, and T2D.
Collapse
|
5
|
Assessment of Ex Vivo Antioxidative Potential of Murine HDL in Atherosclerosis. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2419:283-292. [PMID: 35237971 DOI: 10.1007/978-1-0716-1924-7_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
This chapter provides details on a simple and reproducible method used to determine the capacity of murine HDL to prevent the oxidation of LDL . The principle of the method is based on the rearrangement of double bonds of polyunsaturated fatty acids that occurs during the oxidation of human LDL , which generates a sigmoidal curve. The shape and length of the curve is modified in the presence of HDL , and such modifications are easily quantifiable by measuring the absorbance of conjugated dienes at 234 nm. The general technique described herein may be applied to evaluate the effect of HDL obtained from different experimental murine models of atherosclerosis.
Collapse
|
6
|
Interaction between Apo A-II -265T>C polymorphism and dietary total antioxidant capacity on some anthropometric indices and serum lipid profile in patients with type 2 diabetes mellitus. J Nutr Sci 2021; 10:e9. [PMID: 33889392 PMCID: PMC8057501 DOI: 10.1017/jns.2020.61] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 12/15/2020] [Indexed: 12/22/2022] Open
Abstract
The present study aimed to investigate the interaction of Apo A-II polymorphism and dietary total antioxidant capacity (DTAC) with lipid profile and anthropometric markers in patients with type 2 diabetes (T2DM) that are at risk for atherosclerosis. This cross-sectional study was conducted on 778 patients with T2DM (35–65 years). Dietary intakes were assessed by a 147-item food frequency questionnaire. DTAC was computed using international databases. Participants were categorised into two groups based on rs5082 genotypes. The gene–diet interaction was analysed by an ANCOVA multivariate interaction model. Total cholesterol, TC; triacylglycerol, TG; high- and low-density lipoprotein, HDL and LDL; TC–HDL ratio; waist circumference, WC and body mass index, BMI were obtained according to standard protocols. Overall, the frequency of CC homozygous was 12⋅1 % among study participants. We found that a significant interaction between rs5082 variants and DTAC on mean WC (PTEAC = 0⋅044), TC concentration (PFRAP = 0⋅049 and PTEAC = 0⋅031) and TC/HDL (PFRAP = 0⋅031 and PTRAP = 0⋅040). Among patients whose DTAC was higher than the median intake, the mean of weight, WC and TC/HDL were significantly higher only in individuals with CC genotype. Also, the high DTAC was associated with a lower TC concentration only in T-allele carriers (PFRAP = 0⋅042). We found that adherence to a diet with high total antioxidant capacity can improve the complications of diabetes and atherosclerosis in the T carrier genotype more effectively than the CC genotype. These results could indicate the anti-atherogenic properties of Apo A-II. However, further studies are needed to shed light on this issue.
Collapse
|
7
|
Wang Y, Zhao P, Song Z, Du X, Huo X, Lu J, Liu X, Lv J, Li C, Guo M, Chen Z. Generation of Gene-Knockout Mongolian Gerbils via CRISPR/Cas9 System. Front Bioeng Biotechnol 2020; 8:780. [PMID: 32733872 PMCID: PMC7360674 DOI: 10.3389/fbioe.2020.00780] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 06/18/2020] [Indexed: 12/27/2022] Open
Abstract
The Mongolian gerbil (Meriones unguiculatus), a well-known "multifunctional" experimental animal, plays a crucial role in the research of hearing, cerebrovascular diseases and Helicobacter pylori infection. Although the whole-genome sequencing of Mongolian gerbils has been recently completed, lack of valid gene-editing systems for gerbils largely limited the further usage of Mongolian gerbils in biomedical research. Here, efficient targeted mutagenesis in Mongolian gerbils was successfully conducted by pronuclear injection with Cas9 protein and single-guide RNAs (sgRNAs) targeting Cystatin C (Cst3) or Apolipoprotein A-II (Apoa2). We found that 22 h after human chorionic gonadotropin (hCG) injection, zygote microinjection was conducted, and the injected zygotes were transferred into the pseudopregnant gerbils, which were induced by injecting equine chorionic gonadotropin (eCG) and hCG at a 70 h interval and being caged with ligated male gerbils. We successfully obtained Cst3 and Apoa2 gene knockout gerbils with the knockout efficiencies of 55 and 30.9%, respectively. No off-target effects were detected in all knockout gerbils and the mutations can be germline-transmitted. The absence of CST3 protein was observed in the tissues of homozygous Cst3 knockout (Cst3-KO) gerbils. Interestingly, we found that disruption of the Cst3 gene led to more severe brain damage and neurological deficits after unilateral carotid artery ligation, thereby indicating that the gene modifications happened at both genetic and functional levels. In conclusion, we successfully generated a CRISPR/Cas9 system based genome editing platform for Mongolian gerbils, which provided a foundation for obtaining other genetically modified gerbil models for biomedical research.
Collapse
Affiliation(s)
- Yan Wang
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Peikun Zhao
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Zidai Song
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Xiaoyan Du
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Xueyun Huo
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Jing Lu
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Xin Liu
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Jianyi Lv
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Changlong Li
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Meng Guo
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| | - Zhenwen Chen
- Beijing Key Laboratory of Cancer Invasion and Metastasis Research, School of Basic Medical Science, Capital Medical University, Beijing, China
| |
Collapse
|
8
|
Kajani S, Curley S, McGillicuddy FC. Unravelling HDL-Looking beyond the Cholesterol Surface to the Quality Within. Int J Mol Sci 2018; 19:ijms19071971. [PMID: 29986413 PMCID: PMC6073561 DOI: 10.3390/ijms19071971] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 12/11/2022] Open
Abstract
High-density lipoprotein (HDL) particles have experienced a turbulent decade of falling from grace with widespread demotion from the most-sought-after therapeutic target to reverse cardiovascular disease (CVD), to mere biomarker status. HDL is slowly emerging from these dark times due to the HDL flux hypothesis wherein measures of HDL cholesterol efflux capacity (CEC) are better predictors of reduced CVD risk than static HDL-cholesterol (HDL-C) levels. HDL particles are emulsions of metabolites, lipids, protein, and microRNA (miR) built on the backbone of Apolipoprotein A1 (ApoA1) that are growing in their complexity due to the higher sensitivity of the respective “omic” technologies. Our understanding of particle composition has increased dramatically within this era and has exposed how our understanding of these particles to date has been oversimplified. Elucidation of the HDL proteome coupled with the identification of specific miRs on HDL have highlighted the “hormonal” characteristics of HDL in that it carries and delivers messages systemically. HDL can dock to most peripheral cells via its receptors, including SR-B1, ABCA1, and ABCG1, which may be a critical step for facilitating HDL-to-cell communication. The composition of HDL particles is, in turn, altered in numerous disease states including diabetes, auto-immune disease, and CVD. The consequence of changes in composition, however, on subsequent biological activities of HDL is currently poorly understood and this is an important avenue for the field to explore in the future. Improving HDL particle quality as opposed to HDL quantity may, in turn, prove a more beneficial investment to reduce CVD risk.
Collapse
Affiliation(s)
- Sarina Kajani
- Cardiometabolic Research Group, Diabetes Complications Research Centre, UCD Conway Institute, University College Dublin, Belfield, 4 Dublin, Ireland.
| | - Sean Curley
- Cardiometabolic Research Group, Diabetes Complications Research Centre, UCD Conway Institute, University College Dublin, Belfield, 4 Dublin, Ireland.
| | - Fiona C McGillicuddy
- Cardiometabolic Research Group, Diabetes Complications Research Centre, UCD Conway Institute, University College Dublin, Belfield, 4 Dublin, Ireland.
| |
Collapse
|
9
|
Antioxidative activity of high-density lipoprotein (HDL): Mechanistic insights into potential clinical benefit. BBA CLINICAL 2017; 8:66-77. [PMID: 28936395 PMCID: PMC5597817 DOI: 10.1016/j.bbacli.2017.07.002] [Citation(s) in RCA: 135] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 07/21/2017] [Accepted: 07/24/2017] [Indexed: 12/29/2022]
Abstract
Uptake of low-density lipoprotein (LDL) particles by macrophages represents a key step in the development of atherosclerotic plaques, leading to the foam cell formation. Chemical modification of LDL is however necessary to induce this process. Proatherogenic LDL modifications include aggregation, enzymatic digestion and oxidation. LDL oxidation by one-electron (free radicals) and two-electron oxidants dramatically increases LDL affinity to macrophage scavenger receptors, leading to rapid LDL uptake and fatty streak formation. Circulating high-density lipoprotein (HDL) particles, primarily small, dense, protein-rich HDL3, provide potent protection of LDL from oxidative damage by free radicals, resulting in the inhibition of the generation of pro-inflammatory oxidized lipids. HDL-mediated inactivation of lipid hydroperoxides involves their initial transfer from LDL to HDL and subsequent reduction to inactive hydroxides by redox-active Met residues of apolipoprotein A-I. Several HDL-associated enzymes are present at elevated concentrations in HDL3 relative to large, light HDL2 and can be involved in the inactivation of short-chain oxidized phospholipids. Therefore, HDL represents a multimolecular complex capable of acquiring and inactivating proatherogenic lipids. Antioxidative function of HDL can be impaired in several metabolic and inflammatory diseases. Structural and compositional anomalies in the HDL proteome and lipidome underlie such functional deficiency. Concomitant normalization of the metabolism, circulating levels, composition and biological activities of HDL particles, primarily those of small, dense HDL3, can constitute future therapeutic target.
Collapse
|
10
|
Moradi M, Mahmoudi M, Saedisomeolia A, Mansournia MA, Zahirihashemi R, Koohdani F. Study of the relationship between APOA-II -265T>C polymorphism and HDL function in response to weight loss in overweight and obese type 2 diabetic patients. Clin Nutr 2017; 37:965-969. [PMID: 28457653 DOI: 10.1016/j.clnu.2017.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 03/28/2017] [Accepted: 04/02/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND It has been reported that people may respond differently to the same environmental changes because of genome variations. OBJECTIVE The main purpose of the present study is to determine gene-diet interactions between -265T>C apolipoprotein A-II polymorphisms and evaluate the effect of weight loss on parameters related to HDL function. METHODS In the present study, 56 overweight and obese type 2 diabetic patients were chosen from 697 genotype-specified subjects. After matching for gender, age and BMI, an equal number of patients were chosen for each genotype of APOA-II (TT/TC and CC group). After six-week calorie restriction programme, 44 patients completed the study. Serum paraoxonase-1 (PON1), paraoxonase-3 (PON3), pentraxin-3 (PTX3), and PTX3 gene expression in peripheral blood mononuclear cells were compared between two genotypes and also before and after the intervention separated in each genotype. RESULTS The mean differences of PON enzymes and PTX3 between groups were not significant at the baseline. After weight loss, the mean weight, BMI and serum concentration of PON1 and PON3 decreased significantly and PTX3 increased in total population. Although, the mean differences of PON enzymes and PTX3 between two groups were not significant. However, in comparison of mean differences within the groups, decreased PON3 and increased PTX3 have been observed only in TT group. CONCLUSION A comparison of the mean differences in PON3 and PTX3 within two genotype groups showed that T allele carriers are more sensitive to lifestyle modification, and serum PON3 and PTX3 levels significantly changed only in the TT/TC group.
Collapse
Affiliation(s)
- Masoumeh Moradi
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, International Campus, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Mahmoudi
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Saedisomeolia
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran; Department of Pharmacology, School of Medicine, Western Sydney University, NSW, Australia
| | - Mohammad Ali Mansournia
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Roxana Zahirihashemi
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Fariba Koohdani
- Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, International Campus, Tehran University of Medical Sciences, Tehran, Iran; Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran; Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
11
|
Arora S, Patra SK, Saini R. HDL—A molecule with a multi-faceted role in coronary artery disease. Clin Chim Acta 2016; 452:66-81. [DOI: 10.1016/j.cca.2015.10.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 10/13/2015] [Accepted: 10/22/2015] [Indexed: 01/18/2023]
|
12
|
ZHOU LINGYAN, LI CONGCONG, GAO LING, WANG AIHONG. High-density lipoprotein synthesis and metabolism (Review). Mol Med Rep 2015; 12:4015-4021. [DOI: 10.3892/mmr.2015.3930] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 03/26/2015] [Indexed: 11/06/2022] Open
|
13
|
Rached FH, Chapman MJ, Kontush A. HDL particle subpopulations: Focus on biological function. Biofactors 2015; 41:67-77. [PMID: 25809447 DOI: 10.1002/biof.1202] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/04/2015] [Accepted: 02/07/2015] [Indexed: 12/12/2022]
Abstract
Low levels of high-density lipoprotein-cholesterol (HDL-C) constitute an independent biomarker of cardiovascular morbi-mortality. However, recent advances have drastically modified the classical and limited view of HDL as a carrier of 'good cholesterol', and have revealed unexpected levels of complexity in the circulating HDL particle pool. HDL particles are indeed highly heterogeneous in structure, intravascular metabolism and biological activity. This review describes recent progress in our understanding of HDL subpopulations and their biological activities, and focuses on relationships between the structural, compositional and functional heterogeneity of HDL particles.
Collapse
Affiliation(s)
- Fabiana H Rached
- National Institute for Health and Medical Research (INSERM), UMR-ICAN 1166, Université Pierre et Marie Curie-Paris 6, AP-HP, Pitié-Salpétrière University Hospital, ICAN, Paris, France; Heart Institute-InCor, University of Sao Paulo Medical School Hospital, Sao Paulo, Brazil; Hospital Israelita Albert Einstein, Sao Paulo, Brazil
| | | | | |
Collapse
|
14
|
Riwanto M, Rohrer L, von Eckardstein A, Landmesser U. Dysfunctional HDL: from structure-function-relationships to biomarkers. Handb Exp Pharmacol 2015; 224:337-366. [PMID: 25522994 DOI: 10.1007/978-3-319-09665-0_10] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Reduced plasma levels of HDL-C are associated with an increased risk of CAD and myocardial infarction, as shown in various prospective population studies. However, recent clinical trials on lipid-modifying drugs that increase plasma levels of HDL-C have not shown significant clinical benefit. Notably, in some recent clinical studies, there is no clear association of higher HDL-C levels with a reduced risk of cardiovascular events observed in patients with existing CAD. These observations have prompted researchers to shift from a cholesterol-centric view of HDL towards assessing the function and composition of HDL particles. Of importance, experimental and translational studies have further demonstrated various potential antiatherogenic effects of HDL. HDL has been proposed to promote macrophage reverse cholesterol transport and to protect endothelial cell functions by prevention of oxidation of LDL and its adverse endothelial effects. Furthermore, HDL from healthy subjects can directly stimulate endothelial cell production of nitric oxide and exert anti-inflammatory and antiapoptotic effects. Of note, increasing evidence suggests that the vascular effects of HDL can be highly heterogeneous and HDL may lose important anti-atherosclerotic properties and turn dysfunctional in patients with chronic inflammatory disorders. A greater understanding of mechanisms of action of HDL and its altered vascular effects is therefore critical within the context of HDL-targeted therapies.
Collapse
Affiliation(s)
- Meliana Riwanto
- Cardiology, University Heart Center, University Hospital Zurich and Center of Molecular Cardiology, University of Zurich, Rämistrasse 100, CH 8091, Zurich, Switzerland
| | | | | | | |
Collapse
|
15
|
Apolipoprotein A-II is a key regulatory factor of HDL metabolism as appears from studies with transgenic animals and clinical outcomes. Biochimie 2013; 96:56-66. [PMID: 24012775 DOI: 10.1016/j.biochi.2013.08.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 08/28/2013] [Indexed: 01/26/2023]
Abstract
The structure and metabolism of HDL are linked to their major apolipoproteins (apo) A-I and A-II. HDL metabolism is very dynamic and depends on the constant remodeling by lipases, lipid transfer proteins and receptors. HDL exert several cardioprotective effects, through their antioxidant and antiinflammatory capacities and through the stimulation of reverse cholesterol transport from extrahepatic tissues to the liver for excretion into bile. HDL also serve as plasma reservoir for C and E apolipoproteins, as transport vehicles for a great variety of proteins, and may have more physiological functions than previously recognized. In this review we will develop several aspects of HDL metabolism with emphasis on the structure/function of apo A-I and apo A-II. An important contribution to our understanding of the respective roles of apo A-I and apo A-II comes from studies using transgenic animal models that highlighted the stabilizatory role of apo A-II on HDL through inhibition of their remodeling by lipases. Clinical studies coupled with proteomic analyses revealed the presence of dysfunctional HDL in patients with cardiovascular disease. Beyond HDL cholesterol, a new notion is the functionality of HDL particles. In spite of abundant literature on HDL metabolic properties, a major question remains unanswered: which HDL particle(s) confer(s) protection against cardiovascular risk?
Collapse
|
16
|
Riwanto M, Landmesser U. High density lipoproteins and endothelial functions: mechanistic insights and alterations in cardiovascular disease. J Lipid Res 2013; 54:3227-43. [PMID: 23873269 DOI: 10.1194/jlr.r037762] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Prospective population studies in the primary prevention setting have shown that reduced plasma levels of HDL cholesterol are associated with an increased risk of coronary disease and myocardial infarction. Experimental and translational studies have further revealed several potential anti-atherogenic effects of HDL, including protective effects on endothelial cell functions. HDL has been suggested to protect endothelial cell functions by prevention of oxidation of LDL and its adverse endothelial effects. Moreover, HDL from healthy subjects can directly stimulate endothelial cell production of nitric oxide and anti-inflammatory, anti-apoptotic, and anti-thrombotic effects as well as endothelial repair processes. However, several recent clinical trials using HDL cholesterol-raising agents, such as torcetrapib, dalcetrapib, and niacin, did not demonstrate a significant reduction of cardiovascular events in patients with coronary disease. Of note, growing evidence suggests that the vascular effects of HDL can be highly heterogeneous and vasoprotective properties of HDL are altered in patients with coronary disease. Characterization of underlying mechanisms and understanding of the clinical relevance of this "HDL dysfunction" is currently an active field of cardiovascular research. Notably, in some recent studies no clear association of higher HDL cholesterol levels with a reduced risk of cardiovascular events was observed in patients with already established coronary disease. A greater understanding of mechanisms of action of HDL and its altered vascular effects is therefore critical within the context of HDL-targeted therapies. In this review, we will address different effects of HDL on endothelial cell functions potentially relevant to atherosclerotic vascular disease and explore molecular mechanisms leading to "dysfunctional HDL".
Collapse
Affiliation(s)
- Meliana Riwanto
- Cardiology, University Heart Center, University Hospital Zurich and Cardiovascular Research, Institute of Physiology, Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | | |
Collapse
|
17
|
Sigdel M, Yadav BK, Gyawali P, Regmi P, Baral S, Regmi SR, Jha B. Non-high density lipoprotein cholesterol versus low density lipoprotein cholesterol as a discriminating factor for myocardial infarction. BMC Res Notes 2012; 5:640. [PMID: 23158803 PMCID: PMC3520710 DOI: 10.1186/1756-0500-5-640] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 11/13/2012] [Indexed: 11/25/2022] Open
Abstract
Background Serum total cholesterol (TC) and LDL cholesterol (LDL-C) have been used as major laboratory measures in clinical practice to assess cardiovascular risk in the general population and disease management as well as prognosis in patients. However, some studies have also reported the use of non-HDL cholesterol (non-HDL-C). As non-HDL-C can be calculated by subtracting HDL-C from TC, both of which do not require fasting blood sample in contrast to LDL-C which requires fasting blood sample, we aimed to compare non-HDL-C with LDL-C as a predictor of myocardial infarction (MI). Methods This hospital based cross sectional study was undertaken among 51 cases of MI and equal number of controls. MI was diagnosed based on the clinical history, ECG changes and biochemical parameters. 5 mL of fasting blood sample was collected from each research participant for the analysis of lipid profile. Non-HDL-C was calculated by using the equation; Non-HDL-C = TC – HDL-C. Statistical analysis was performed using SPSS 14.0. Results 42 MI cases were dyslipidemic in contrast to 20 dyslipidemic subjects under control group. The differences in the median values of each lipid parameter were statistically significant between MI cases and controls. The lipid risk factors most strongly associated with MI were HDL-C (OR 5.85, 95% CI 2.41-14.23, P value = 0.000) followed by non-HDL-C (OR 3.77, 95% CI 1.64-8.66, P value = 0.002), LDL-C/HDL-C (OR 3.38, 95% CI 1.44-7.89, P value = 0.005), TC/HDL-C (OR 2.93, 95% CI 1.36-7.56, P value = 0.026), LDL-C (OR 2.70, 95% CI 1.20-6.10, P value = 0.017), TC (OR 2.68, 95% CI 1.04-6.97, P value = 0.042) and Tg (OR 2.54, 95% CI 1.01-6.39, P value = 0.047). Area under the receiver operating curve was greater for non-HDL-C than for LDL-C. Non-HDL-C was also found to be more sensitive and specific than LDL-C for MI. Conclusions HDL-C and non-HDL-C are better discriminating parameters than LDL-C for MI. Thus, we can simply perform test for HDL-C and non-HDL-C both of which do not require fasting blood sample rather than waiting for fasting blood sample to measure LDL-C.
Collapse
Affiliation(s)
- Manoj Sigdel
- Department of Biochemistry, Manipal College of Medical Sciences, Pokhara, Nepal.
| | | | | | | | | | | | | |
Collapse
|
18
|
Corsetti JP, Bakker SJL, Sparks CE, Dullaart RPF. Apolipoprotein A-II influences apolipoprotein E-linked cardiovascular disease risk in women with high levels of HDL cholesterol and C-reactive protein. PLoS One 2012; 7:e39110. [PMID: 22723940 PMCID: PMC3377620 DOI: 10.1371/journal.pone.0039110] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 05/17/2012] [Indexed: 11/19/2022] Open
Abstract
Background In a previous report by our group, high levels of apolipoprotein E (apoE) were demonstrated to be associated with risk of incident cardiovascular disease in women with high levels of C-reactive protein (CRP) in the setting of both low (designated as HR1 subjects) and high (designated as HR2 subjects) levels of high-density lipoprotein cholesterol (HDL-C). To assess whether apolipoprotein A-II (apoA-II) plays a role in apoE-associated risk in the two female groups. Methodology/Principal Outcome event mapping, a graphical data exploratory tool; Cox proportional hazards multivariable regression; and curve-fitting modeling were used to examine apoA-II influence on apoE-associated risk focusing on HDL particles with apolipoprotein A-I (apoA-I) without apoA-II (LpA-I) and HDL particles with both apoA-I and apoA-II (LpA-I:A-II). Results of outcome mappings as a function of apoE levels and the ratio of apoA-II to apoA-I revealed within each of the two populations, a high-risk subgroup characterized in each situation by high levels of apoE and additionally: in HR1, by a low value of the apoA-II/apoA-I ratio; and in HR2, by a moderate value of the apoA-II/apoA-I ratio. Furthermore, derived estimates of LpA-I and LpA-I:A-II levels revealed for high-risk versus remaining subjects: in HR1, higher levels of LpA-I and lower levels of LpA-I:A-II; and in HR2 the reverse, lower levels of LpA-I and higher levels of LpA-I:A-II. Results of multivariable risk modeling as a function of LpA-I and LpA-I:A-II (dichotomized as highest quartile versus combined three lower quartiles) revealed association of risk only for high levels of LpA-I:A-II in the HR2 subgroup (hazard ratio 5.31, 95% CI 1.12–25.17, p = 0.036). Furthermore, high LpA-I:A-II levels interacted with high apoE levels in establishing subgroup risk. Conclusions/Significance We conclude that apoA-II plays a significant role in apoE-associated risk of incident CVD in women with high levels of HDL-C and CRP.
Collapse
Affiliation(s)
- James P Corsetti
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA.
| | | | | | | |
Collapse
|
19
|
Relationship between concentration difference of different density lipoproteins and shear stress in atherosclerosis. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2012; 2012:135256. [PMID: 22481972 PMCID: PMC3310262 DOI: 10.1155/2012/135256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 10/16/2011] [Accepted: 11/08/2011] [Indexed: 02/05/2023]
Abstract
Previous research has observed concentration polarization in LDL and HDL in the arterial system. However, there is no report that links this concentration polarization to the development of vascular atherosclerosis (AS). Therefore, the purpose of this study is to establish the relationship between concentration difference of LDL and HDL and shear stress using a carotid bifurcation vascular model. PTFE was employed to create the carotid bifurcation model. Endothelial cells were coated on the inner wall of the graft. In a recirculation system, HDL and LDL concentration were measured under two different ICA flow velocities at 5 different locations within our model. We report the following: (1) LDL and HDL concentration difference was observed in both high flow and low flow environments; (2) the degree of LDL and HDL concentration polarization varied depending of high flow and low flow environment; (3) absolute values of concentration difference between LDL and HDL at the inner wall surface decreased with the increase in shear stress when shear stress was more than 1.5 Pa. This variation trend would be more pronounced if shear stress were less than 0.5 Pa. Our study suggests that under the action of shear stress, concentration differences of LDL or HDL create a disturbance in the balance of atherogenic factors and anti-As factors, resulting in the occurrence of AS.
Collapse
|
20
|
Abstract
Oxidative stress, an emerging risk factor for premature atherosclerosis and cardiovascular disease, mediates the formation of proinflammatory, pro-atherogenic oxidized low-density lipoprotein (oxLDL) in the arterial intima. Circulating HDL particles, and particularly small, dense, protein-rich HDL3, may provide potent protection of LDL in vivo from oxidative damage by free radicals in the arterial intima, resulting in the inhibition of the generation of proinflammatory oxidized lipids, primarily lipid hydroperoxides (LOOH) but also short-chain oxidized phospholipids (oxPL). HDL-mediated inactivation of LOOH involves initial transfer of phospholipid hydroperoxides (PLOOH) from LDL to HDL3, which is governed by the rigidity of the surface monolayer of HDL, and subsequent reduction of PLOOH by redox-active Met residues of apolipoprotein A-I (apoA-I) with the formation of phospholipid hydroxides (PLOH) and methionine sulphoxides. HDL-associated enzymes may in turn contribute to the hydrolytic inactivation of short-chain oxPL. Mounting evidence suggests that the integrated antioxidative activity of HDL appear to be defective in atherogenic dyslipidaemias involving low HDL-cholesterol levels; anomalies in the proteome and lipidome of HDL particles in dyslipidaemic patients may underlie such functional deficiency. Pharmacological normalization of HDL metabolism concomitantly with correction of circulating levels, composition and biological activities of HDL particles, with enrichment in apoA-I and reduction in HDL surface rigidity, may constitute an efficacious therapeutic approach to attenuate atherosclerosis in dyslipidaemic patients at high cardiovascular risk.
Collapse
Affiliation(s)
- Anatol Kontush
- National Institute for Health and Medical Research (INSERM), Dyslipidemia, Inflammation and Atherosclerosis Research Unit (UMR 939), Paris, France.
| | | |
Collapse
|
21
|
Podrez EA. Anti-oxidant properties of high-density lipoprotein and atherosclerosis. Clin Exp Pharmacol Physiol 2010; 37:719-25. [PMID: 20374263 DOI: 10.1111/j.1440-1681.2010.05380.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
1. High-density lipoprotein (HDL) is one of the major carriers of cholesterol in the blood. It attracts particular attention because, in contrast with other lipoproteins, many physiological functions of HDL influence the cardiovascular system in favourable ways unless HDL is modified pathologically. 2. The best known function of HDL is the capacity to promote cellular cholesterol efflux from peripheral cells and deliver cholesterol to the liver for excretion, thereby playing a key role in reverse cholesterol transport. The functions of HDL that have recently attracted attention include anti-inflammatory and anti-oxidant activities. High anti-oxidant and anti-inflammatory activities of HDL are associated with protection from cardiovascular disease. 3. Atheroprotective activities, as well as a functional deficiency of HDL, ultimately depend on the protein and lipid composition of HDL. Conversely, these activities are compromised in many pathological states associated with inflammation. 4. The focus of the present review is on the anti-oxidant and anti-inflammatory functions of HDL and its individual components in relation to protection from atherosclerosis.
Collapse
Affiliation(s)
- Eugene A Podrez
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
| |
Collapse
|
22
|
Concentration polarization of high-density lipoprotein and its relation with shear stress in an in vitro model. J Biomed Biotechnol 2009; 2009:695838. [PMID: 19753319 PMCID: PMC2742649 DOI: 10.1155/2009/695838] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 06/05/2009] [Accepted: 06/20/2009] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to determine the concentration polarization of high-density lipoprotein (HDL) at the surface of the carotid artery under conditions of steady flow and to establish its relationship with shear stress using an in vitro vascular simulation model of carotid bifurcation. Shear stress, HDL concentration at the surface, and the ratio of HDL concentration at the surface to concentration in bulk flow were measured at different locations within the model under high-speed (1.451 m/s) and low-speed (0.559 m/s) flow. HDL showed concentration polarization at the surface of the carotid artery model, particularly in the internal carotid artery sinus. With decreasing flow velocity, the shear stress at the surface also decreased, and HDL concentration polarization increased. The concentration polarization of HDL was negatively and strongly correlated with shear stress at both low- (r = −0.872, P < .001) and high-speed flow (r = −0.592, P = .0018).
Collapse
|
23
|
Gomaraschi M, Sinagra G, Serdoz LV, Pitzorno C, Fonda M, Cattin L, Calabresi L, Franceschini G. The plasma concentration of Lpa-I:A-II particles as a predictor of the inflammatory response in patients with ST-elevation myocardial infarction. Atherosclerosis 2009; 202:304-11. [DOI: 10.1016/j.atherosclerosis.2008.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Revised: 04/02/2008] [Accepted: 04/05/2008] [Indexed: 11/25/2022]
|
24
|
White CR, Datta G, Zhang Z, Gupta H, Garber DW, Mishra VK, Palgunachari MN, Handattu SP, Chaddha M, Anantharamaiah GM. HDL therapy for cardiovascular diseases: the road to HDL mimetics. Curr Atheroscler Rep 2008; 10:405-12. [PMID: 18706282 DOI: 10.1007/s11883-008-0063-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are currently the drug of choice for the clinical management of elevated low-density lipoprotein (LDL) cholesterol. Although statin treatment provides an overall improvement in outcomes, clinical trial data reveal a significant number of cardiac events despite reaching targeted LDL levels. A low serum high-density lipoprotein (HDL) cholesterol level is an independent predictor of cardiovascular risk. Accordingly, there has been interest in determining whether HDL elevation, in addition to LDL lowering, further reduces risk in patients with coronary artery disease. Several commonly prescribed lipid-lowering therapies modestly raise HDL, but their use may be limited by the development of adverse reactions. Emerging data suggest that HDL quality and function may also be significantly reduced by atherosclerosis and other inflammatory diseases. The goal of this review is to discuss the current status of HDL therapeutics, with emphasis on a novel class of agent, the apolipoprotein A-I mimetic peptides, which improve the functional properties of HDL cholesterol.
Collapse
Affiliation(s)
- C Roger White
- Vascular Biology and Hypertension Program, University of Alabama, Birmingham, 1046 Zeigler Research Building, 703 South 19th Street, Birmingham, AL 35294, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Moren X, Deakin S, Liu ML, Taskinen MR, James RW. HDL subfraction distribution of paraoxonase-1 and its relevance to enzyme activity and resistance to oxidative stress. J Lipid Res 2008; 49:1246-53. [DOI: 10.1194/jlr.m700439-jlr200] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
26
|
Delgado-Lista J, Perez-Jimenez F, Tanaka T, Perez-Martinez P, Jimenez-Gomez Y, Marin C, Ruano J, Parnell L, Ordovas JM, Lopez-Miranda J. An apolipoprotein A-II polymorphism (-265T/C, rs5082) regulates postprandial response to a saturated fat overload in healthy men. J Nutr 2007; 137:2024-8. [PMID: 17709437 DOI: 10.1093/jn/137.9.2024] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Apolipoprotein (Apo) A-II is an apolipoprotein with an unknown role in lipid metabolism. It has been suggested that the presence of the less frequent allele of a single nucleotide polymorphism (Apo A-II -265T/C, rs5082) reduces the transcription rate of Apo A-II and enhances VLDL postprandial clearance in middle-aged men. To further investigate the role of Apo A-II -265T/C on lipid metabolism, we studied 88 normolipidemic young men. The participants were given a fatty meal containing 1 g fat and 7 mg cholesterol/kg weight and capsules containing 60,000 IU vitamin A (retinyl palmitate, 15.15 mg RE) per square meter body surface area. Postprandial lipemia was assessed during the 11 h following the meal. Total cholesterol (Chol) and triacylglycerols (TG) in plasma and TG-rich lipoproteins (TRL) (large TRL and small TRL) were measured, as well as HDL, Apo A-I, Apo B, Apo B-48, and Apo B-100. Postprandial responses were higher in the TT group than in carriers of the minor allele (CC/TC) for total TG in plasma (21.37% of change of area under curve, P = 0.014), large TRL-TG (24.75% change, P = 0.017) and small TRL-Chol (26.63% change, P = 0.003). Our work shows that carriers of the minor allele for Apo A-II -265T/C (CC/TC) have a lower postprandial response compared with TT homozygotes. This finding may partially explain the role of Apo A-II in lipid metabolism and can identify a population with a decreased risk of cardiovascular disease, as corresponds to the lower level of postprandial hypertriglyceridemia.
Collapse
Affiliation(s)
- Javier Delgado-Lista
- Lipids and Atherosclerosis Research Unit, Reina Sofía University Hospital, Córdoba, Spain
| | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Kontush A, Chapman MJ. Functionally defective high-density lipoprotein: a new therapeutic target at the crossroads of dyslipidemia, inflammation, and atherosclerosis. Pharmacol Rev 2006; 58:342-74. [PMID: 16968945 DOI: 10.1124/pr.58.3.1] [Citation(s) in RCA: 533] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
High-density lipoproteins (HDL) possess key atheroprotective biological properties, including cellular cholesterol efflux capacity, and anti-oxidative and anti-inflammatory activities. Plasma HDL particles are highly heterogeneous in physicochemical properties, metabolism, and biological activity. Within the circulating HDL particle population, small, dense HDL particles display elevated cellular cholesterol efflux capacity, afford potent protection of atherogenic low-density lipoprotein against oxidative stress and attenuate inflammation. The antiatherogenic properties of HDL can, however be compromised in metabolic diseases associated with accelerated atherosclerosis. Indeed, metabolic syndrome and type 2 diabetes are characterized not only by elevated cardiovascular risk and by low HDL-cholesterol (HDL-C) levels but also by defective HDL function. Functional HDL deficiency is intimately associated with alterations in intravascular HDL metabolism and structure. Indeed, formation of HDL particles with attenuated antiatherogenic activity is mechanistically related to core lipid enrichment in triglycerides and cholesteryl ester depletion, altered apolipoprotein A-I (apoA-I) conformation, replacement of apoA-I by serum amyloid A, and covalent modification of HDL protein components by oxidation and glycation. Deficient HDL function and subnormal HDL-C levels may act synergistically to accelerate atherosclerosis in metabolic disease. Therapeutic normalization of attenuated antiatherogenic HDL function in terms of both particle number and quality of HDL particles is the target of innovative pharmacological approaches to HDL raising, including inhibition of cholesteryl ester transfer protein, enhanced lipidation of apoA-I with nicotinic acid and infusion of reconstituted HDL or apoA-I mimetics. A preferential increase in circulating concentrations of HDL particles possessing normalized antiatherogenic activity is therefore a promising therapeutic strategy for the treatment of common metabolic diseases featuring dyslipidemia, inflammation, and premature atherosclerosis.
Collapse
Affiliation(s)
- Anatol Kontush
- Dyslipoproteinemia and Atherosclerosis Research Unit, National Institute for Health and Medical Research, Hôpital de la Pitié, 83 boulevard de l'Hôpital, 75651 Paris Cedex 13, France.
| | | |
Collapse
|
28
|
Karasawa K. Clinical aspects of plasma platelet-activating factor-acetylhydrolase. Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1359-72. [PMID: 17049457 DOI: 10.1016/j.bbalip.2006.06.017] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2006] [Accepted: 06/15/2006] [Indexed: 11/25/2022]
Abstract
Plasma platelet-activating factor (PAF)-acetylhydrolase (PAF-AH), which is characterized by tight association with plasma lipoproteins, degrades not only PAF but also phospholipids with oxidatively modified short fatty acyl chain esterified at the sn-2 position. Production and accumulation of these phospholipids are associated with the onset of inflammatory diseases and preventive role of this enzyme has been evidenced by many recent studies including prevalence of the genetic deficiency of the enzyme in the patients and therapeutic effects of treatment with recombinant protein or gene transfer. With respect to the atherosclerosis, however, it is not fully cleared whether this enzyme plays an anti-atherogenic role or pro-atherogenic role because plasma PAF-AH also might produce lysophosphatidylcholine (LysoPC) and oxidatively modified nonesterified fatty acids with potent pro-inflammatory and pro-atherogenic bioactivities. These dual roles of plasma PAF-AH might be regulated by the altered distribution of the enzyme between low density lipoprotein (LDL) and high density lipoprotein (HDL) particles because HDL-associated enzymes are considered to contribute to the protection of LDL from oxidative modification. This review focuses on the recent findings which address the role of this enzyme in the human diseases especially including asthma, septic shock and atherosclerosis.
Collapse
Affiliation(s)
- Ken Karasawa
- Laboratory of Molecular Pharmaceutics, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamihara, Kanagawa 199-0195, Japan.
| |
Collapse
|
29
|
Karabina SA, Ninio E. Plasma PAF-acetylhydrolase: an unfulfilled promise? Biochim Biophys Acta Mol Cell Biol Lipids 2006; 1761:1351-8. [PMID: 16807087 DOI: 10.1016/j.bbalip.2006.05.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Revised: 05/04/2006] [Accepted: 05/08/2006] [Indexed: 01/04/2023]
Abstract
Plasma Platelet-activating-Factor (PAF)-acetylhydrolase (PAF-AH also named lipoprotein-PLA(2) or PLA(2)G7 gene) is secreted by macrophages, it degrades PAF and oxidation products of phosphatidylcholine produced upon LDL oxidation and/or oxidative stress, and thus is considered as a potentially anti-inflammatory enzyme. Cloning of PAF-AH has sustained tremendous promises towards the use of PAF-AH recombinant protein in clinical situations. The reason for that stems from the numerous animal models of inflammation, atherosclerosis or sepsis, where raising the levels of circulating PAF-AH either through recombinant protein infusion or through the adenoviral gene transfer showed to be beneficial. Unfortunately, neither in human asthma nor in sepsis the recombinant PAF-AH showed sufficient efficacy. One of the most challenging questions nowadays is as to whether PAF-AH is pro- or anti-atherogenic in humans, as PAF-AH may possess a dual pro- and anti-inflammatory role, depending on the concentration and the availability of potential substrates. It is equally possible that the plasma level of PAF-AH is a diagnostic marker of ongoing atherosclerosis.
Collapse
Affiliation(s)
- Sonia-Athina Karabina
- INSERM U525, Université Pierre et Marie Curie-Paris6, Faculté de Médecine Pierre et Marie Curie, 91, bd de l'Hôpital 75634 Paris cedex 13, France
| | | |
Collapse
|
30
|
Gaidukov L, Tawfik DS. High Affinity, Stability, and Lactonase Activity of Serum Paraoxonase PON1 Anchored on HDL with ApoA-I. Biochemistry 2005; 44:11843-54. [PMID: 16128586 DOI: 10.1021/bi050862i] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Serum paraoxonase (PON1) is a high-density lipoprotein (HDL)-associated enzyme exhibiting antiatherogenic properties. This study examined the interaction of recombinant PON1 with reconstituted HDL comprised of PC, cholesterol, and various apolipoproteins (apoA-I, -II, and -IV). The affinity, stability, and lactonase activity were strongly correlated, with apoA-I exhibiting the strongest effects, apoA-IV exhibiting weaker yet significant effects, and apoA-II having a negative effect relative to protein-free particles. We found that PON1 binds apoA-I HDL with sub-nanomolar affinities (K(d) << 10(-)(9) M) and slow dissociation rates (t(1/2) > 80 min), while binding affinity for other particles was dramatically lower. A truncated form of PON1 lacking the N-terminal helix maintains considerable binding to apoA-I HDL (K(d) = 1.2 x 10(-)(7) M), validating the structural model which indicates additional parts of the enzyme involved in HDL binding. Kinetic inactivation assays revealed the existence of an equilibrium between two forms of PON1 differing in their stability by a factor of 100. Various lipoproteins and detergent preparations shift this equilibrium toward the more stable conformation. Consistent with its highest affinity, only apoA-I HDL is capable of totally shifting the equilibrium toward the stable form. The paraoxonase and arylesterase activities were stimulated by HDL by 2-5-fold as previously reported, almost independently of the apoliporotein content. In contrast, only apoA-I is capable of stimulating the lactonase activity by <or=20-fold to k(cat)/K(M) values of 10(6)-10(7) M(-)(1) s(-)(1), while apoA-IV and apoA-II have almost no effect. Overall, the results indicate the high stability, selectivity, and catalytic proficiency of PON1 when anchored onto apoA-I HDL, toward lactone substrates, and lipophilic lactones in particular.
Collapse
Affiliation(s)
- Leonid Gaidukov
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | | |
Collapse
|
31
|
Deakin S, Moren X, James RW. Very low density lipoproteins provide a vector for secretion of paraoxonase-1 from cells. Atherosclerosis 2005; 179:17-25. [PMID: 15721005 DOI: 10.1016/j.atherosclerosis.2004.08.039] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Revised: 08/13/2004] [Accepted: 08/31/2004] [Indexed: 02/04/2023]
Abstract
Paraoxonase-1 (PON1) requires a suitable acceptor complex for its secretion from producing cells. The serum lipoprotein, high-density lipoprotein (HDL) has been shown to accomplish this function, whereas low-density lipoproteins are ineffective. The present study examined the influence of the third serum lipoprotein subclass, very low density lipoproteins (VLDL), on PON1 secretion. VLDL were shown to promote secretion of PON1 from a transfected Chinese hamster ovary model and from transfected hepatocytes in a high-affinity, saturable manner. The effects of HDL and VLDL were not additive, suggesting that they may employ a common secretion pathway. VLDL was able to stabilise secreted PON1 enzyme activity, but less effectively than stabilisation by HDL. Following co-incubation of VLDL and HDL, the majority of PON1 accumulated in HDL even if HDL was added after initial association of the enzyme with VLDL. VLDL to HDL transfer of PON1 was rapid and did not require lipolysis of VLDL. Low levels of active PON1 were associated with VLDL in human serum, and VLDL-associated enzyme activity was proportional to serum triglyceride concentrations. Serum triglycerides were positively associated with whole serum PON1 mass but negatively associated with specific activity. PON1-enriched VLDL was more resistant to oxidation in vitro. The present study suggests that the triglyceride transport vector, VLDL, can modulate PON1 metabolism and activity. This is due, in part, to an influence of the lipoprotein on PON1 secretion. PON1 was associated with VLDL in human serum, where triglycerides correlated independently with variations in serum mass and activity of the enzyme. VLDL-associated PON1 exerted an anti-oxidative effect, which may be of physiological benefit.
Collapse
Affiliation(s)
- Sara Deakin
- Clinical Diabetes Unit, Division of Endocrinology, Diabetology and Nutrition, Medical Faculty, University Hospital, 1211 Geneva 14, Switzerland
| | | | | |
Collapse
|
32
|
Chait A, Han CY, Oram JF, Heinecke JW. Thematic review series: The Immune System and Atherogenesis. Lipoprotein-associated inflammatory proteins: markers or mediators of cardiovascular disease? J Lipid Res 2005; 46:389-403. [PMID: 15722558 DOI: 10.1194/jlr.r400017-jlr200] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
In humans, a chronically increased circulating level of C-reactive protein (CRP), a positive acute-phase reactant, is an independent risk factor for cardiovascular disease. This observation has led to considerable interest in the role of inflammatory proteins in atherosclerosis. In this review, after discussing CRP, we focus on the potential role in the pathogenesis of human vascular disease of inflammation-induced proteins that are carried by lipoproteins. Serum amyloid A (SAA) is transported predominantly on HDL, and levels of this protein increase markedly during acute and chronic inflammation in both animals and humans. Increased SAA levels predict the risk of cardiovascular disease in humans. Recent animal studies support the proposal that SAA plays a role in atherogenesis. Evidence is accruing that secretory phospholipase A(2), an HDL-associated protein, and platelet-activating factor acetylhydrolase, a protein associated predominantly with LDL in humans and HDL in mice, might also play roles both as markers and mediators of human atherosclerosis. In contrast to positive acute-phase proteins, which increase in abundance during inflammation, negative acute-phase proteins have received less attention. Apolipoprotein A-I (apoA-I), the major apolipoprotein of HDL, decreases during inflammation. Recent studies also indicate that HDL is oxidized by myeloperoxidase in patients with established atherosclerosis. These alterations may limit the ability of apoA-I to participate in reverse cholesterol transport. Paraoxonase-1 (PON1), another HDL-associated protein, also decreases during inflammation. PON1 is atheroprotective in animal models of hypercholesterolemia. Controversy over its utility as a marker of human atherosclerosis may reflect the fact that enzyme activity rather than blood level (or genotype) is the major determinant of cardiovascular risk. Thus, multiple lipoprotein-associated proteins that change in concentration during acute and chronic inflammation may serve as markers of cardiovascular disease. In future studies, it will be important to determine whether these proteins play a causal role in atherogenesis.
Collapse
Affiliation(s)
- Alan Chait
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA 98195, USA.
| | | | | | | |
Collapse
|
33
|
James RW, Deakin SP. The importance of high-density lipoproteins for paraoxonase-1 secretion, stability, and activity. Free Radic Biol Med 2004; 37:1986-94. [PMID: 15544917 DOI: 10.1016/j.freeradbiomed.2004.08.012] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2004] [Revised: 08/10/2004] [Accepted: 08/12/2004] [Indexed: 11/30/2022]
Abstract
The association of paraoxonase-1 (PON1) with high-density lipoproteins (HDL) is a prerequisite for maintaining normal serum activity of the enzyme. The lipoprotein furnishes an amphipathic environment to shield the hydrophobic, N-terminal region of the enzyme, and such an environment may also be necessary for interaction of PON1 with its substrates. HDL provides the optimal physiological acceptor complex, in terms of both stimulating PON1 secretion and stabilizing the secreted peptide. Lipid and peptide components of HDL contribute to these effects, such that modulating HDL composition influences PON1 activity and function. In this context, understanding how PON1 associates with HDL, what governs the association, and the mechanism by which the PON1-HDL complex exerts its antioxidant function is of particular physiological relevance. Moreover, HDL is subject to substantial compositional variations under both normal and pathological metabolic conditions. It has implications for the influence of the enzyme on cardiovascular risk, as normal enzyme activity may not correlate with optimal functional (antioxidant) efficiency. We review evidence that HDL lipid and protein components interact to promote PON1 secretion and maintain serum enzyme activity. Emerging data on how the enzyme associates with HDL are discussed, and the consequences for PON1 function of modifications to HDL are outlined. Finally, we highlight questions concerning the HDL-PON1 association that remain unanswered but are of particular importance in defining PON1 efficiency.
Collapse
Affiliation(s)
- Richard W James
- Clinical Diabetes Unit, Division of Endocrinology, Diabetes, and Nutrition, Faculty of Medicine, University Hospital, 24 Rue Micheli-du-Crest, 1211 Geneva 14, Switzerland.
| | | |
Collapse
|
34
|
Wu A, Hinds CJ, Thiemermann C. High-density lipoproteins in sepsis and septic shock: metabolism, actions, and therapeutic applications. Shock 2004; 21:210-21. [PMID: 14770033 DOI: 10.1097/01.shk.0000111661.09279.82] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Sepsis and septic shock are important causes of morbidity and lethality in noncoronary intensive care units. Circulating levels of high-density lipoproteins (HDLs) are reduced in sepsis/septic shock, and the magnitude of this reduction is positively correlated with the severity of the illness. The mechanisms underlying this phenomenon are incompletely understood, although increased levels of several acute-phase proteins, including serum amyloid A (SAA) and secretory phospholipase A2 (sPLA2), may contribute to the decrease in plasma HDLs. It has been suggested that HDLs possess anti-inflammatory properties and, hence, may play a crucial role in innate immunity by regulating the inflammatory response as well as being capable of reducing the severity of organ injury in animals and patients with septic shock. These protective effects of HDLs are mediated mainly via (a) lipopolysaccharide (LPS) binding and neutralization, (b) the HDL-associated enzymes, plasma paraoxonase (PON1) and platelet-activating factor acetylhydrolase (PAF-AH), which protect low-density lipoproteins against peroxidative damage, (c) inhibition of the expression of endothelial cell adhesion molecules and release of proinflammatory cytokines, which prevents inflammatory cell infiltration and subsequent multiple organ dysfunction, and (d) stimulation of the expression of endothelial nitric oxide synthase (eNOS). Thus, HDL exerts potent anti-inflammatory effects, some of which are independent of endotoxin binding and might be useful in the treatment of patients with not only sepsis/septic shock but also other conditions associated with an uncontrolled inflammatory response, such as ischemia-reperfusion injury and hemorrhagic shock.
Collapse
Affiliation(s)
- Aihua Wu
- Department of Anaesthesia, Beijing Hospital, Beijing 100730, PR China
| | | | | |
Collapse
|
35
|
Ribas V, Sánchez-Quesada JL, Antón R, Camacho M, Julve J, Escolà-Gil JC, Vila L, Ordóñez-Llanos J, Blanco-Vaca F. Human Apolipoprotein A-II Enrichment Displaces Paraoxonase From HDL and Impairs Its Antioxidant Properties. Circ Res 2004; 95:789-97. [PMID: 15388641 DOI: 10.1161/01.res.0000146031.94850.5f] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Apolipoprotein A-II (apoA-II), the second major high-density lipoprotein (HDL) apolipoprotein, has been linked to familial combined hyperlipidemia. Human apoA-II transgenic mice constitute an animal model for this proatherogenic disease. We studied the ability of human apoA-II transgenic mice HDL to protect against oxidative modification of apoB-containing lipoproteins. When challenged with an atherogenic diet, antigens related to low-density lipoprotein (LDL) oxidation were markedly increased in the aorta of 11.1 transgenic mice (high human apoA-II expressor). HDL from control mice and 11.1 transgenic mice were coincubated with autologous very LDL (VLDL) or LDL, or with human LDL under oxidative conditions. The degree of oxidative modification of apoB lipoproteins was then evaluated by measuring relative electrophoretic mobility, dichlorofluorescein fluorescence, 9- and 13-hydroxyoctadecadienoic acid content, and conjugated diene kinetics. In all these different approaches, and in contrast to control mice, HDL from 11.1 transgenic mice failed to protect LDL from oxidative modification. A decreased content of apoA-I, paraoxonase (PON1), and platelet-activated factor acetyl-hydrolase activities was found in HDL of 11.1 transgenic mice. Liver gene expression of these HDL-associated proteins did not differ from that of control mice. In contrast, incubation of isolated human apoA-II with control mouse plasma at 37°C decreased PON1 activity and displaced the enzyme from HDL. Thus, overexpression of human apoA-II in mice impairs the ability of HDL to protect apoB-containing lipoproteins from oxidation. Further, the displacement of PON1 by apoA-II could explain in part why PON1 is mostly found in HDL particles with apoA-I and without apoA-II, as well as the poor antiatherogenic properties of apoA-II–rich HDL.
Collapse
Affiliation(s)
- Vicent Ribas
- Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Asztalos BF. High-density lipoprotein metabolism and progression of atherosclerosis: new insights from the HDL Atherosclerosis Treatment Study. Curr Opin Cardiol 2004; 19:385-91. [PMID: 15218401 DOI: 10.1097/01.hco.0000126979.41946.7e] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE OF REVIEW The purpose of this review is to summarize the current understanding of the potentially antiatherogenic properties of high-density lipoprotein related to its different components. RECENT FINDINGS Recent findings on the role of the different high-density lipoprotein subspecies in reverse cholesterol transport, inflammation, endothelial dysfunction, and low-density lipoprotein oxidation are covered. Special emphasis is put on the heterogeneity of high-density lipoprotein and functional changes related to specific high-density lipoprotein particles with the potential therapeutic alterations of high-density lipoprotein metabolism. SUMMARY The diverse action of high-density lipoprotein observed could be explained by the heterogeneity of high-density lipoprotein particles with completely different composition and properties. The modification of specific high-density lipoprotein subpopulations to reach the maximum atheroprotective effects under various pathologic conditions bears great potential in lipid research.
Collapse
Affiliation(s)
- Bela F Asztalos
- Lipid Metabolism Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts 02111, USA.
| |
Collapse
|
37
|
Kontush A, Chantepie S, Chapman MJ. Small, dense HDL particles exert potent protection of atherogenic LDL against oxidative stress. Arterioscler Thromb Vasc Biol 2003; 23:1881-8. [PMID: 12920049 DOI: 10.1161/01.atv.0000091338.93223.e8] [Citation(s) in RCA: 315] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The relationship of the structural and functional heterogeneity of HDL particles to protection of LDL against oxidative stress is indeterminate. METHODS AND RESULTS HDL subfractions of defined physicochemical properties were isolated by density gradient ultracentrifugation from normolipidemic human serum (n=8), and their capacity to protect LDL from oxidation was evaluated. Under mild oxidative stress induced by AAPH or Cu(II), HDL subfractions (at equal cholesterol or protein concentration or equal particle number) significantly decreased LDL oxidation rate (-20% to -85%) in the propagation phase (234 nm), which was prolonged by up to 82% with decreased maximal diene formation. Antioxidative activity of HDL subfractions increased with increment in density, as follows: HDL2b<HDL2a<HDL3a<HDL3b<HDL3c (confirmed by thiobarbituric acid-reactive substance content and LDL electrophoretic mobility). Concordantly, antioxidative activity of small HDL prepared by FPLC was significantly higher (+56%) than that of large HDL. Antioxidative action of HDL subfractions was primarily associated with inactivation of LDL lipid hydroperoxides. The potent protective activity of small HDL could not be accounted for exclusively by enzymatic activities (PON1, platelet-activating factor acetylhydrolase, and lecithin-cholesterol acyltransferase). CONCLUSIONS Small, dense HDL exhibit potent antioxidant activity, which may arise from synergy in inactivation of oxidized LDL lipids by enzymatic and nonenzymatic mechanisms, in part reflecting distinct intrinsic physicochemical properties.
Collapse
Affiliation(s)
- Anatol Kontush
- Dyslipoproteinemia and Atherosclerosis Research Unit (U.551), National Institute for Health and Medical Research (INSERM), Hôpital de la Pitié, Paris, France.
| | | | | |
Collapse
|
38
|
Caslake MJ, Packard CJ. Lipoprotein-associated phospholipase A2 (platelet-activating factor acetylhydrolase) and cardiovascular disease. Curr Opin Lipidol 2003; 14:347-52. [PMID: 12865731 DOI: 10.1097/00041433-200308000-00002] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Plasma lipoproteins carry a number of highly active enzymes in the circulation. One of these is lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), also known as platelet-activating factor acetylhydrolase. This review addresses the molecular properties of Lp-PLA(2), the controversy surrounding its role in atherosclerosis and the regulation of its plasma levels in humans. RECENT FINDINGS Recent reports indicate that the enzyme Lp-PLA(2) found in both LDL and HDL may be independently regulated in these lipoprotein subclasses and have distinct roles in atherogenesis. Seminal findings establishing the response-to-retention hypothesis of atherosclerosis support further the potentially damaging role that in-situ release of LDL-associated oxidative products by Lp-PLA(2) may have in the formation of arterial wall lesions. In the mouse, where Lp-PLA(2) circulates mainly bound to HDL, overexpression leads to reduced atherosclerosis, raising the possibility that the enzyme in HDL may have a protective role. Further evidence for a potential protective role is seen in studies of partial or complete deficiency of the enzyme. In the more general setting of population studies, however, it is clear that Lp-PLA(2) is a positive risk factor for coronary disease and measurements of its mass may contribute to the prediction of coronary heart disease risk, especially in individuals with low LDL cholesterol levels. SUMMARY Lp-PLA(2) is an enzyme with potentially multiple risks in atherosclerosis. In humans the weight of evidence suggests that it is a positive risk factor for coronary heart disease - an observation commensurate with its position in the direct pathological sequence leading from formation of oxidized LDL in the artery wall to cellular dysfunction and formation of lesions.
Collapse
Affiliation(s)
- Muriel J Caslake
- Department of Pathological Biochemistry, Glasgow Royal Infirmary, Glasgow, UK.
| | | |
Collapse
|
39
|
|
40
|
Kalopissis AD, Pastier D, Chambaz J. Apolipoprotein A-II: beyond genetic associations with lipid disorders and insulin resistance. Curr Opin Lipidol 2003; 14:165-72. [PMID: 12642785 DOI: 10.1097/00041433-200304000-00008] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
PURPOSE OF REVIEW Apolipoprotein A-II, the second major HDL apolipoprotein, was often considered of minor importance relatively to apolipoprotein A-I and its role was controversial. This picture is now rapidly changing, due to novel polymorphisms and mutations, to the outcome of clinical trials, and to studies with transgenic mice. RECENT FINDINGS The -265 T/C polymorphism supports a role for apolipoprotein A-II in postprandial very-low-density lipoprotein metabolism. Fibrates, which increase apolipoprotein A-II synthesis, significantly decrease the incidence of major coronary artery disease events, particularly in subjects with low HDL cholesterol, high plasma triglyceride, and high body weight. The comparison of transgenic mice overexpressing human or murine apolipoprotein A-II has highlighted major structural differences between the two proteins; they have opposite effects on HDL size, apolipoprotein A-I content, plasma concentration, and protection from oxidation. Human apolipoprotein A-II is more hydrophobic, displaces apolipoprotein A-I from HDL, accelerates apolipoprotein A-I catabolism, and its plasma concentration is decreased by fasting. Apolipoprotein A-II stimulates ATP binding cassette transporter 1-mediated cholesterol efflux. Human and murine apolipoprotein A-II differently affect glucose metabolism and insulin resistance. A novel beneficial role for apolipoprotein A-II in the pathogenesis of hepatitis C virus has been shown. SUMMARY The hydrophobicity of human apolipoprotein A-II is a key regulatory factor of HDL metabolism. Due to the lower plasma apolipoprotein A-II concentration during fasting, measurements of apolipoprotein A-II in fed subjects are more relevant. More clinical studies are necessary to clarify the role of apolipoprotein A-II in well-characterized subsets of patients and in the insulin resistance syndrome.
Collapse
Affiliation(s)
- Athina-Despina Kalopissis
- Unité 505 INSERM, Centre de Recherche des Cordeliers, 15 rue de l'Ecole de Médecine, 75006 Paris, France.
| | | | | |
Collapse
|