1
|
Xiao Q, Wang J, Wang L, Ding H. APOA1/C3/A4/A5 Gene Cluster at 11q23.3 and Lipid Metabolism Disorders: From Epigenetic Mechanisms to Clinical Practices. Biomedicines 2024; 12:1224. [PMID: 38927431 PMCID: PMC11201263 DOI: 10.3390/biomedicines12061224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 05/26/2024] [Accepted: 05/29/2024] [Indexed: 06/28/2024] Open
Abstract
The APOA1/C3/A4/A5 cluster is an essential component in regulating lipoprotein metabolism and maintaining plasma lipid homeostasis. A genome-wide association analysis and Mendelian randomization have revealed potential associations between genetic variants within this cluster and lipid metabolism disorders, including hyperlipidemia and cardiovascular events. An enhanced understanding of the complexity of gene regulation has led to growing recognition regarding the role of epigenetic variation in modulating APOA1/C3/A4/A5 gene expression. Intensive research into the epigenetic regulatory patterns of the APOA1/C3/A4/A5 cluster will help increase our understanding of the pathogenesis of lipid metabolism disorders and facilitate the development of new therapeutic approaches. This review discusses the biology of how the APOA1/C3/A4/A5 cluster affects circulating lipoproteins and the current progress in the epigenetic regulation of the APOA1/C3/A4/A5 cluster.
Collapse
Affiliation(s)
- Qianqian Xiao
- Division of Cardiology, Departments of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; (Q.X.); (J.W.); (L.W.)
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan 430030, China
| | - Jing Wang
- Division of Cardiology, Departments of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; (Q.X.); (J.W.); (L.W.)
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan 430030, China
| | - Luyun Wang
- Division of Cardiology, Departments of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; (Q.X.); (J.W.); (L.W.)
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan 430030, China
| | - Hu Ding
- Division of Cardiology, Departments of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; (Q.X.); (J.W.); (L.W.)
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan 430030, China
| |
Collapse
|
2
|
Kim J, Baek Y, Lee S. Consumption of dietary fiber and APOA5 genetic variants in metabolic syndrome: baseline data from the Korean Medicine Daejeon Citizen Cohort Study. Nutr Metab (Lond) 2024; 21:19. [PMID: 38581036 PMCID: PMC10998362 DOI: 10.1186/s12986-024-00793-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 03/13/2024] [Indexed: 04/07/2024] Open
Abstract
BACKGROUND Consumption of dietary fiber has been suggested as an important aspect of a healthy diet to reduce the risk of metabolic syndrome (MetS), including cardiovascular disease. The role of fiber intake in MetS might differ by individual genetic susceptibility. APOA5 encodes a regulator of plasma triglyceride levels, which impacts the related mechanisms of MetS. This study investigated the association between dietary fiber and the risk of MetS, assessing their associations according to APOA5 genetic variants. METHODS A total of 1985 participants aged 30-55 years were included from a cross-sectional study based on the Korean Medicine Daejeon Citizen Cohort study at baseline (2017-2019). Dietary fiber intake was measured using a semiquantitative food frequency questionnaire. The APOA5 polymorphisms (rs2266788 A > G, rs662799 A > G, and rs651821 T > C) were genotyped using the Asia Precision Medicine Research Array. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS A higher consumption of dietary fiber was associated with a lower prevalence of MetS (P = 0.025). Among the components of MetS, an inverse association with dietary fiber was observed in increased waist circumference (OR, 95% CI = 0.60, 0.41-0.88, P for trend = 0.009) and elevated triglycerides (OR, 95% CI = 0.69, 0.50-0.96, P for trend = 0.012). Regarding the interaction with APOA5 genetic variants, a stronger association with dietary fiber intake was shown in G allele carriers of rs662799 than in A/A carriers (OR, 95% CI = 2.34, 1.59-3.44, P for interaction = 0.024) and in C allele carriers of rs651821 than in T/T carriers (OR, 95% CI = 2.35, 1.59-3.46, P for interaction = 0.027). CONCLUSIONS The findings of this study suggest that the benefits of dietary fiber on the risk of MetS could be modified by genetic variants of the APOA5 gene, providing a more effective strategy for preventing MetS.
Collapse
Affiliation(s)
- Jimi Kim
- Department of Food and Nutrition, Changwon National University, 20 Changwondaehak-ro, Uichang-gu, 51140, Changwon, Gyeongnam, South Korea
| | - Younghwa Baek
- Korean Medicine Data Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, 34054, Daejeon, South Korea
| | - Siwoo Lee
- Korean Medicine Data Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, 34054, Daejeon, South Korea.
| |
Collapse
|
3
|
Perera SD, Hegele RA. Genetic variation in apolipoprotein A-V in hypertriglyceridemia. Curr Opin Lipidol 2024; 35:66-77. [PMID: 38117614 PMCID: PMC10919278 DOI: 10.1097/mol.0000000000000916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
PURPOSE OF REVIEW While biallelic rare APOA5 pathogenic loss-of-function (LOF) variants cause familial chylomicronemia syndrome, heterozygosity for such variants is associated with highly variable triglyceride phenotypes ranging from normal to severe hypertriglyceridemia, often in the same individual at different time points. Here we provide an updated overview of rare APOA5 variants in hypertriglyceridemia. RECENT FINDINGS Currently, most variants in APOA5 that are considered to be pathogenic according to guidelines of the American College of Medical Genetics and Genomics are those resulting in premature termination codons. There are minimal high quality functional data on the impact of most rare APOA5 missense variants; many are considered as variants of unknown or uncertain significance. Furthermore, particular common polymorphisms of APOA5 , such as p.Ser19Trp and p.Gly185Cys in Caucasian and Asian populations, respectively, are statistically overrepresented in hypertriglyceridemia cohorts and are sometimes misattributed as being causal for chylomicronemia, when they are merely risk alleles for hypertriglyceridemia. SUMMARY Both biallelic and monoallelic LOF variants in APOA5 are associated with severe hypertriglyceridemia, although the biochemical phenotype in the monoallelic state is highly variable and is often exacerbated by secondary factors. Currently, with few exceptions, the principal definitive mechanism for APOA5 pathogenicity is through premature truncation. The pathogenic mechanisms of most missense variants in APOA5 remain unclear and require additional functional experiments or family studies.
Collapse
Affiliation(s)
- Shehan D Perera
- Departments of Biochemistry and Medicine, Schulich School of Medicine and Dentistry, Western University, 1151 Richmond Street North, London, Ontario, Canada
| | | |
Collapse
|
4
|
Wheless A, Gunn KH, Neher SB. Macromolecular Interactions of Lipoprotein Lipase (LPL). Subcell Biochem 2024; 104:139-179. [PMID: 38963487 DOI: 10.1007/978-3-031-58843-3_8] [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: 07/05/2024]
Abstract
Lipoprotein lipase (LPL) is a critical enzyme in humans that provides fuel to peripheral tissues. LPL hydrolyzes triglycerides from the cores of lipoproteins that are circulating in plasma and interacts with receptors to mediate lipoprotein uptake, thus directing lipid distribution via catalytic and non-catalytic functions. Functional losses in LPL or any of its myriad of regulators alter lipid homeostasis and potentially affect the risk of developing cardiovascular disease-either increasing or decreasing the risk depending on the mutated protein. The extensive LPL regulatory network tunes LPL activity to allocate fatty acids according to the energetic needs of the organism and thus is nutritionally responsive and tissue dependent. Multiple pharmaceuticals in development manipulate or mimic these regulators, demonstrating their translational importance. Another facet of LPL biology is that the oligomeric state of the enzyme is also central to its regulation. Recent structural studies have solidified the idea that LPL is regulated not only by interactions with other binding partners but also by self-associations. Here, we review the complexities of the protein-protein and protein-lipid interactions that govern LPL structure and function.
Collapse
Affiliation(s)
- Anna Wheless
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kathryn H Gunn
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Stony Brook University, Stony Brook, USA
| | - Saskia B Neher
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| |
Collapse
|
5
|
Stankov S, Vitali C, Park J, Nguyen D, Mayne L, Englander SW, Levin MG, Vujkovic M, Hand NJ, Phillips MC, Rader DJ. Comparison of the structure-function properties of wild-type human apoA-V and a C-terminal truncation associated with elevated plasma triglycerides. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.02.21.23286268. [PMID: 36865344 PMCID: PMC9980232 DOI: 10.1101/2023.02.21.23286268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Background Plasma triglycerides (TGs) are causally associated with coronary artery disease and acute pancreatitis. Apolipoprotein A-V (apoA-V, gene APOA5) is a liver-secreted protein that is carried on triglyceride-rich lipoproteins and promotes the enzymatic activity of lipoprotein lipase (LPL), thereby reducing TG levels. Little is known about apoA-V structure-function; naturally occurring human APOA5 variants can provide novel insights. Methods We used hydrogen-deuterium exchange mass spectrometry to determine the secondary structure of human apoA-V in lipid-free and lipid-associated conditions and identified a C-terminal hydrophobic face. Then, we used genomic data in the Penn Medicine Biobank to identify a rare variant, Q252X, predicted to specifically eliminate this region. We interrogated the function of apoA-V Q252X using recombinant protein in vitro and in vivo in apoa5 knockout mice. Results Human apoA-V Q252X carriers exhibited elevated plasma TG levels consistent with loss of function. Apoa5 knockout mice injected with AAV vectors expressing wildtype and variant APOA5-AAV recapitulated this phenotype. Part of the loss of function is due to reduced mRNA expression. Functionally, recombinant apoA-V Q252X was more readily soluble in aqueous solutions and more exchangeable with lipoproteins than WT apoA-V. Despite lacking the C-terminal hydrophobic region (a putative lipid binding domain) this protein also decreased plasma TG in vivo. Conclusions Deletion of apoA-V's C-terminus leads to reduced apoA-V bioavailability in vivo and higher TG levels. However, the C-terminus is not required for lipoprotein binding or enhancement of intravascular lipolytic activity. WT apoA-V is highly prone to aggregation, and this property is markedly reduced in recombinant apoA-V lacking the C-terminus.
Collapse
Affiliation(s)
- Sylvia Stankov
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Cecilia Vitali
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph Park
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David Nguyen
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Leland Mayne
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - S. Walter Englander
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Michael G. Levin
- Division of Cardiovascular Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Marijana Vujkovic
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA
| | - Nicholas J. Hand
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael C. Phillips
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel J. Rader
- Division of Translational Medicine and Human Genetics, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
6
|
Apolipoprotein A-V is a potential target for treating coronary artery disease: evidence from genetic and metabolomic analyses. J Lipid Res 2022; 63:100193. [PMID: 35278410 PMCID: PMC9062431 DOI: 10.1016/j.jlr.2022.100193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 02/14/2022] [Accepted: 02/28/2022] [Indexed: 11/22/2022] Open
Abstract
Triglyceride (TG)-lowering LPL variants in combination with genetic LDL-C-lowering variants are associated with reduced risk of coronary artery disease (CAD). Genetic variation in the APOA5 gene encoding apolipoprotein A-V also strongly affects TG levels, but the potential clinical impact and underlying mechanisms are yet to be resolved. Here, we aimed to study the effects of APOA5 genetic variation on CAD risk and plasma lipoproteins through factorial genetic association analyses. Using data from 309,780 European-ancestry participants from the UK Biobank, we evaluated the effects of lower TG levels as a result of genetic variation in APOA5 and/or LPL on CAD risk with or without a background of reduced LDL-C. Next, we compared lower TG levels via APOA5 and LPL variation with over 100 lipoprotein measurements in a combined sample from the Netherlands Epidemiology of Obesity study (N = 4,838) and the Oxford Biobank (N = 6,999). We found that lower TG levels due to combined APOA5 and LPL variation and genetically-influenced lower LDL-C levels afforded the largest reduction in CAD risk (odds ratio: 0.78 (0.73-0.82)). Compared to patients with genetically-influenced lower TG via LPL, genetically-influenced lower TG via APOA5 had similar and independent, but notably larger, effects on the lipoprotein profile. Our results suggest that lower TG levels as a result of APOA5 variation have strong beneficial effects on CAD risk and the lipoprotein profile, which suggest apo A-V may be a potential novel therapeutic target for CAD prevention.
Collapse
|
7
|
Apolipoprotein A5, a unique modulator of fasting and postprandial triglycerides. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159185. [DOI: 10.1016/j.bbalip.2022.159185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/30/2022] [Accepted: 05/13/2022] [Indexed: 11/19/2022]
|
8
|
Low-density lipoprotein receptor and apolipoprotein A 5, myocardial infarction biomarkers in plasma-derived exosomes. J Cardiol 2022; 79:605-610. [DOI: 10.1016/j.jjcc.2021.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 09/16/2021] [Accepted: 09/21/2021] [Indexed: 11/20/2022]
|
9
|
Heeren J, Scheja L. Metabolic-associated fatty liver disease and lipoprotein metabolism. Mol Metab 2021; 50:101238. [PMID: 33892169 PMCID: PMC8324684 DOI: 10.1016/j.molmet.2021.101238] [Citation(s) in RCA: 210] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/01/2021] [Accepted: 04/15/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Non-alcoholic fatty liver disease, or as recently proposed 'metabolic-associated fatty liver disease' (MAFLD), is characterized by pathological accumulation of triglycerides and other lipids in hepatocytes. This common disease can progress from simple steatosis to steatohepatitis, and eventually end-stage liver diseases. MAFLD is closely related to disturbances in systemic energy metabolism, including insulin resistance and atherogenic dyslipidemia. SCOPE OF REVIEW The liver is the central organ in lipid metabolism by secreting very low density lipoproteins (VLDL) and, on the other hand, by internalizing fatty acids and lipoproteins. This review article discusses recent research addressing hepatic lipid synthesis, VLDL production, and lipoprotein internalization as well as the lipid exchange between adipose tissue and the liver in the context of MAFLD. MAJOR CONCLUSIONS Liver steatosis in MAFLD is triggered by excessive hepatic triglyceride synthesis utilizing fatty acids derived from white adipose tissue (WAT), de novo lipogenesis (DNL) and endocytosed remnants of triglyceride-rich lipoproteins. In consequence of high hepatic lipid content, VLDL secretion is enhanced, which is the primary cause of complex dyslipidemia typical for subjects with MAFLD. Interventions reducing VLDL secretory capacity attenuate dyslipidemia while they exacerbate MAFLD, indicating that the balance of lipid storage versus secretion in hepatocytes is a critical parameter determining disease outcome. Proof of concept studies have shown that promoting lipid storage and energy combustion in adipose tissues reduces hepatic lipid load and thus ameliorates MAFLD. Moreover, hepatocellular triglyceride synthesis from DNL and WAT-derived fatty acids can be targeted to treat MAFLD. However, more research is needed to understand how individual transporters, enzymes, and their isoforms affect steatosis and dyslipidemia in vivo, and whether these two aspects of MAFLD can be selectively treated. Processing of cholesterol-enriched lipoproteins appears less important for steatosis. It may, however, modulate inflammation and consequently MAFLD progression.
Collapse
Affiliation(s)
- Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Ludger Scheja
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| |
Collapse
|
10
|
The Importance of Lipoprotein Lipase Regulation in Atherosclerosis. Biomedicines 2021; 9:biomedicines9070782. [PMID: 34356847 PMCID: PMC8301479 DOI: 10.3390/biomedicines9070782] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/02/2021] [Accepted: 07/04/2021] [Indexed: 02/07/2023] Open
Abstract
Lipoprotein lipase (LPL) plays a major role in the lipid homeostasis mainly by mediating the intravascular lipolysis of triglyceride rich lipoproteins. Impaired LPL activity leads to the accumulation of chylomicrons and very low-density lipoproteins (VLDL) in plasma, resulting in hypertriglyceridemia. While low-density lipoprotein cholesterol (LDL-C) is recognized as a primary risk factor for atherosclerosis, hypertriglyceridemia has been shown to be an independent risk factor for cardiovascular disease (CVD) and a residual risk factor in atherosclerosis development. In this review, we focus on the lipolysis machinery and discuss the potential role of triglycerides, remnant particles, and lipolysis mediators in the onset and progression of atherosclerotic cardiovascular disease (ASCVD). This review details a number of important factors involved in the maturation and transportation of LPL to the capillaries, where the triglycerides are hydrolyzed, generating remnant lipoproteins. Moreover, LPL and other factors involved in intravascular lipolysis are also reported to impact the clearance of remnant lipoproteins from plasma and promote lipoprotein retention in capillaries. Apolipoproteins (Apo) and angiopoietin-like proteins (ANGPTLs) play a crucial role in regulating LPL activity and recent insights into LPL regulation may elucidate new pharmacological means to address the challenge of hypertriglyceridemia in atherosclerosis development.
Collapse
|
11
|
Abstract
The apolipoproteins are well known for their roles in both health and disease, as components of plasma lipoprotein particles, such as high-density lipoprotein (HDL), low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL), chylomicrons, and metabolic, vascular- and inflammation-related disorders, such as cardiovascular disease, atherosclerosis, metabolic syndrome, and diabetes. Increasingly, their roles in neurovascular and neurodegenerative disorders are also being elucidated. They play major roles in lipid and cholesterol transport between blood and organs and are, therefore, critical to maintenance and homeostasis of the lipidome, with apolipoprotein-lipid interactions, including cholesterol, fatty acids, triglycerides, phospholipids, and isoprostanes. Further, they have important pleiotropic roles related to aging and longevity, which are largely managed through their many structural variants, including multiple isoforms, and a diversity of post-translational modifications. Consequently, tools for the characterization and accurate quantification of apolipoproteins, including their diverse array of variant forms, are required to understand their salutary and disease related roles. In this chapter we outline three distinct quantitative approaches suitable for targeting apolipoproteins: (1) multiplex immunoassays, (2) mass spectrometric immunoassay, and (3) multiple reaction monitoring, mass spectrometric quantification. We also discuss management of pre-analytical and experimental design variables.
Collapse
|
12
|
Talbot H, Saada S, Naves T, Gallet PF, Fauchais AL, Jauberteau MO. Regulatory Roles of Sortilin and SorLA in Immune-Related Processes. Front Pharmacol 2019; 9:1507. [PMID: 30666202 PMCID: PMC6330335 DOI: 10.3389/fphar.2018.01507] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/10/2018] [Indexed: 12/25/2022] Open
Abstract
Sortilin, also known as Neurotensin Receptor-3, and the sorting-related receptor with type-A repeats (SorLA) are both members of the Vps10p domain receptor family. Initially identified in CNS cells, they are expressed in various other cell types where they exert multiple functions. Although mostly studied for its involvement in Alzheimer’s disease, SorLA has recently been shown to be implicated in immune response by regulating IL-6-mediated signaling, as well as driving monocyte migration. Sortilin has been shown to act as a receptor, as a co-receptor and as an intra- and extracellular trafficking regulator. In the last two decades, deregulation of sortilin has been demonstrated to be involved in many human pathophysiologies, including neurodegenerative disorders (Alzheimer and Parkinson diseases), type 2 diabetes and obesity, cancer, and cardiovascular pathologies such as atherosclerosis. Several studies highlighted different functions of sortilin in the immune system, notably in microglia, pro-inflammatory cytokine regulation, phagosome fusion and pathogen clearance. In this review, we will analyze the multiple roles of sortilin and SorLA in the human immune system and how their deregulation may be involved in disease development.
Collapse
Affiliation(s)
- Hugo Talbot
- Faculty of Medicine, University of Limoges, Limoges, France
| | - Sofiane Saada
- Faculty of Medicine, University of Limoges, Limoges, France
| | - Thomas Naves
- Faculty of Medicine, University of Limoges, Limoges, France
| | | | - Anne-Laure Fauchais
- Faculty of Medicine, University of Limoges, Limoges, France.,Department of Internal Medicine, University Hospital Limoges Dupuytren Hospital, Limoges, France
| | - Marie-Odile Jauberteau
- Faculty of Medicine, University of Limoges, Limoges, France.,Department of Immunology, University Hospital Limoges Dupuytren Hospital, Limoges, France
| |
Collapse
|
13
|
Hua S, Ma C, Zhang J, Li J, Wu W, Xu N, Luo G, Zhao J. Influence of APOA5 Locus on the Treatment Efficacy of Three Statins: Evidence From a Randomized Pilot Study in Chinese Subjects. Front Pharmacol 2018; 9:352. [PMID: 29695967 PMCID: PMC5904201 DOI: 10.3389/fphar.2018.00352] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 03/27/2018] [Indexed: 12/22/2022] Open
Abstract
Pharmacogenetics or pharmacogenomics approaches are important for addressing the individual variabilities of drug efficacy especially in the era of precision medicine. One particular interesting gene to investigate is APOA5, which has been repeatedly linked with the inter-individual variations of serum triglycerides. Here, we explored APOA5-statin interactions in 195 Chinese subjects randomized to rosuvastatin (5–10 mg/day), atorvastatin (10–20 mg/day), or simvastatin (40 mg/day) for 12 weeks by performing a targeted genotyping analysis of the APOA5 promoter SNP rs662799 (-1131T > C). There were no significant differences between the treatment arms for any of the statin-induced changes in clinical biomarkers. Reductions in LDL cholesterol were influenced by the APOA5 genotype in all three treatment groups. By contrast, changes in HDL cholesterol, and triglycerides were only affected by the APOA5 genotype in the atorvastatin and simvastatin groups and not in the rosuvastatin group. Our results suggest that future studies may need to consider stratifying subjects not only by genetic background but also by prescribed statin type.
Collapse
Affiliation(s)
- Sha Hua
- Department of Cardiology, Ruijin Hospital Luwan Branch, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Chuanxiang Ma
- Department of Pathology, Affiliated Hospital of Weifang Medical University, Weifang, China
| | - Jun Zhang
- Comprehensive Laboratory, Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Jing Li
- Department of Cardiology, Ruijin Hospital Luwan Branch, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Weiwei Wu
- Department of Cardiology, Ruijin Hospital Luwan Branch, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Ning Xu
- Section of Clinical Chemistry and Pharmacology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Guanghua Luo
- Comprehensive Laboratory, Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Jianrong Zhao
- Department of Cardiology, Ruijin Hospital Luwan Branch, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
14
|
Luo J, Xu L, Li J, Zhao S. Effects and mechanisms of apolipoprotein A-V on the regulation of lipid accumulation in cardiomyocytes. Lipids Health Dis 2018. [PMID: 29530023 PMCID: PMC5848552 DOI: 10.1186/s12944-018-0692-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background Apolipoprotein (apo) A-V is a key regulator of triglyceride (TG) metabolism. We investigated effects of apoA-V on lipid metabolism in cardiomyocytes in this study. Methods We first examined whether apoA-V can be taken up by cardiomyocytes and whether low density lipoprotein receptor family members participate in this process. Next, triglyceride (TG) content and lipid droplet changes were detected at different concentrations of apoA-V in normal and lipid-accumulation cells in normal and obese animals. Finally, we tested the levels of fatty acids (FAs) taken up into cardiomyocytes and lipid secretion through [14C]-oleic acid. Results Our results show that heart tissue has apoA-V protein, and apoA-V is taken up by cardiomyocytes. When HL-1 cells were transfected with low density lipoprotein receptor (LDLR)-related protein 1(LRP1) siRNA, apoA-V intake decreased by 53% (P<0.05), while a 37% lipid accumulation in HL-1 cells remain unchanged. ApoA-V localized to the cytoplasm and was associated with lipid droplets in HL-1 cells. A 1200 and 1800 ng/mL apoA-V intervention decreased TG content by 28% and 45% in HL-1 cells, respectively and decreased TG content by 39% in mouse heart tissue (P<0.05). However, apoA-V had no effects on TG content in either normal HL-1 cells or mice. The levels of FAs taken up into cardiomyocytes decreased by 43% (P < 0.05), and the levels of TG and cholesterol ester secretion increased by 1.2-fold and 1.6-fold, respectively (P < 0.05). Conclusion ApoA-V is a novel regulator of lipid metabolism in cardiomyocytes.
Collapse
Affiliation(s)
- Jun Luo
- Department of Cardiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
| | - Li Xu
- Department of The Second Chest Medicine, The Affiliated Cancer Hospital of Xiangya School of medicine, Central South University, Changsha, Hunan, 410013, China
| | - Jiang Li
- Department of Cardiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China.
| | - Shuiping Zhao
- Department of Cardiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China.
| |
Collapse
|
15
|
Zhao SP, Li R, Dai W, Yu BL, Chen LZ, Huang XS. Xuezhikang contributes to greater triglyceride reduction than simvastatin in hypertriglyceridemia rats by up-regulating apolipoprotein A5 via the PPARα signaling pathway. PLoS One 2017; 12:e0184949. [PMID: 28934253 PMCID: PMC5608289 DOI: 10.1371/journal.pone.0184949] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 09/01/2017] [Indexed: 11/18/2022] Open
Abstract
Xuezhikang (XZK), an extract of Chinese red yeast rice, is recommended as an optimal choice for patients with coronary heart disease (CHD) with markedly elevated triglyceride (TG) levels. This study was designed to compare the hypotriglyceridemic effects between XZK and simvastatin. The role of apolipoprotein A5 (apoA5), a key regulator of TG metabolism and a target gene of peroxisome proliferator-activated receptor α (PPARα), was to be identified in XZK-related hypotriglyceridemic actions. For these goals, hypertriglyceridemia of rats was induced by a high-fructose diet. In order to investigate the hypotriglyceridemic effects of XZK and simvastatin on these animals based on an equivalent low-density lipoprotein cholesterol (LDL-C) lowering power, we titrated their doses (XZK 80 mg/kg/d versus simvastatin 1 mg/kg/d) according to plasma LDL-C reduction of rats. Similarly, we titrated the target doses of the two agents (XZK 500 μg/ml versus simvastatin 10 μM) according to hepatocyte LDL receptor expressions, and then compared the effects of the two agents on TG and apoA5 of hepatocytes in vitro. Our results showed that XZK (80 mg/kg/d) had higher hypotriglyceridemic performance than simvastatin (1 mg/kg/d) on these animals albeit their equivalent LDL-C lowering power. Higher plasma apoA5 levels and hepatic apoA5 expressions were observed in rats treated with XZK (80 mg/kg/d) than simvastatin (1 mg/kg/d). Further, XZK (80 mg/kg/d) contributed to higher hepatic PPARα expressions of rats than simvastatin (1 mg/kg/d). Although the two agents led to an equivalent up-regulation of LDL receptors of hepatocytes, more TG reduction and apoA5 elevation were detected in hepatocytes treated with XZK (500 μg/ml) than simvastatin (10 μM). However, PPARα knockdown eliminated the above effects of XZK on hepatocytes. Therefore, our study indicates that XZK has greater hypotriglyceridemic performance than simvastatin in the setting of an equivalent LDL-C lowering power, which is attributed to more apoA5 up-regulation by this agent via the PPARα signaling pathway.
Collapse
Affiliation(s)
- Shui-ping Zhao
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Rong Li
- Department of Stomatology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wen Dai
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Bi-lian Yu
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Lu-zhu Chen
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xian-sheng Huang
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- * E-mail:
| |
Collapse
|
16
|
Guardiola M, Ribalta J. Update on APOA5 Genetics: Toward a Better Understanding of Its Physiological Impact. Curr Atheroscler Rep 2017; 19:30. [DOI: 10.1007/s11883-017-0665-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
17
|
Schmidt V, Subkhangulova A, Willnow TE. Sorting receptor SORLA: cellular mechanisms and implications for disease. Cell Mol Life Sci 2016; 74:1475-1483. [PMID: 27832290 PMCID: PMC5357279 DOI: 10.1007/s00018-016-2410-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 11/01/2016] [Accepted: 11/03/2016] [Indexed: 12/21/2022]
Abstract
Sorting-related receptor with A-type repeats (SORLA) is an intracellular sorting receptor that directs cargo proteins, such as kinases, phosphatases, and signaling receptors, to their correct location within the cell. The activity of SORLA assures proper function of cells and tissues, and receptor dysfunction is the underlying cause of common human malignancies, including Alzheimer’s disease, atherosclerosis, and obesity. Here, we discuss the molecular mechanisms that govern sorting of SORLA and its cargo in multiple cell types, and why genetic defects in this receptor results in devastating diseases.
Collapse
Affiliation(s)
- Vanessa Schmidt
- Max-Delbrueck-Center for Molecular Medicine, Robert-Roessle-Str. 10, 13125, Berlin, Germany.
| | - Aygul Subkhangulova
- Max-Delbrueck-Center for Molecular Medicine, Robert-Roessle-Str. 10, 13125, Berlin, Germany
| | - Thomas E Willnow
- Max-Delbrueck-Center for Molecular Medicine, Robert-Roessle-Str. 10, 13125, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
| |
Collapse
|
18
|
Zhu J, Xu K, Zhang X, Cao J, Jia Z, Yang R, Ma C, Chen C, Zhang T, Yan Z. Studies on the regulation of lipid metabolism and its mechanism of the iridoids rich fraction in Valeriana jatamansi Jones. Biomed Pharmacother 2016; 84:1891-1898. [PMID: 27832992 DOI: 10.1016/j.biopha.2016.10.099] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 10/16/2016] [Accepted: 10/31/2016] [Indexed: 12/27/2022] Open
Abstract
Valeriana jatamansi Jones, a plant with heart-shaped leaves in the Valeriana genus of Valerianaceae, is widely used in Chinese folk medicine. Iridoid is an important constituent of V. jatamansi that contributes to the pharmacological efficacy of the herb. This study aims to investigate the regulation of lipid metabolism and its mechanism of the iridoids rich fraction in V. jatamansi (IRFV). A high fat diet was used to establish the hyperlipidemia rat model, with 2mg/kg/d of simvastatin as a positive control, fed with 7.5, 15, and 30mg/kg/d of IRFV for 20days to investigate the lipid regulation activity and mechanism of IRFV. Body weight, liver index, total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in both serum and liver, as well as total bile acid (TBA), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in serum were measured. The lipoprotein lipase (LPL) and hepatic lipase (HL) activities and the apoprotein A5 (ApoA5), peroxisome proliferator-activated receptor α (PPAR-α), sterol regulatory element-binding proteins (SREBP-1c), and liver X receptor α (LXR-α) protein expressions were observed. Liver pathology was described through hematoxylin-eosin (HE) staining. Compared with the model group, three different IRFV dosages can slow down the weight gain of rats, reduce the contents of TG, and increase the contents of HDL-C in serum. Low IRFV dosage can significantly reduce the AST and ALT contents in serum, liver index, and the TG contents in liver, enhance LPL activity. Medium IRFV dosage can significantly decrease the TG and LDL-C contents in liver. High IRFV dosage can significantly reduce LDL-C, TBA, AST, and ALT contents in serum, and enhance HL activity. Three different IRFV dosages can significantly increase the ApoA5 and PPAR-α protein expression and decrease the SREBP-1c protein expression. Furthermore, the LXR-α protein expression decreased in low- and high-dose groups. Liver tissue pathological observation showed that IRFV can improve cell degeneration to a certain extent. These results strongly suggest that IRFV play significant roles in regulating lipid metabolism, the mechanism may be related to the increased ApoA5 protein expression.
Collapse
Affiliation(s)
- Jiali Zhu
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Keke Xu
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Xuemei Zhang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Jiahong Cao
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Zhanrong Jia
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Ruocong Yang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Chaoying Ma
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Chang Chen
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, PR China
| | - Tiane Zhang
- School of Basic Medicine, Chengdu University of Traditional Chinese Medicine,Chengdu 611137, PR China.
| | - Zhiyong Yan
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China.
| |
Collapse
|
19
|
Metformin ameliorates obesity-associated hypertriglyceridemia in mice partly through the apolipoprotein A5 pathway. Biochem Biophys Res Commun 2016; 478:1173-8. [DOI: 10.1016/j.bbrc.2016.08.087] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 08/15/2016] [Indexed: 12/17/2022]
|
20
|
Doherty CM, Visse R, Dinakarpandian D, Strickland DK, Nagase H, Troeberg L. Engineered Tissue Inhibitor of Metalloproteinases-3 Variants Resistant to Endocytosis Have Prolonged Chondroprotective Activity. J Biol Chem 2016; 291:22160-22172. [PMID: 27582494 PMCID: PMC5063997 DOI: 10.1074/jbc.m116.733261] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Indexed: 01/03/2023] Open
Abstract
Tissue inhibitor of metalloproteinases-3 (TIMP-3) is a central inhibitor of matrix-degrading and sheddase families of metalloproteinases. Extracellular levels of the inhibitor are regulated by the balance between its retention on the extracellular matrix and its endocytic clearance by the scavenger receptor low density lipoprotein receptor-related protein 1 (LRP1). Here, we used molecular modeling to predict TIMP-3 residues potentially involved in binding to LRP1 based on the proposed LRP1 binding motif of 2 lysine residues separated by about 21 Å and mutated the candidate lysine residues to alanine individually and in pairs. Of the 22 mutants generated, 13 displayed a reduced rate of uptake by HTB94 chondrosarcoma cells. The two mutants (TIMP-3 K26A/K45A and K42A/K110A) with lowest rates of uptake were further evaluated and found to display reduced binding to LRP1 and unaltered inhibitory activity against prototypic metalloproteinases. TIMP-3 K26A/K45A retained higher affinity for sulfated glycosaminoglycans than K42A/K110A and exhibited increased affinity for ADAMTS-5 in the presence of heparin. Both mutants inhibited metalloproteinase-mediated degradation of cartilage at lower concentrations and for longer than wild-type TIMP-3, indicating that their increased half-lives improved their ability to protect cartilage. These mutants may be useful in treating connective tissue diseases associated with increased metalloproteinase activity.
Collapse
Affiliation(s)
- Christine M Doherty
- From the Arthritis Research UK Centre for Osteoarthritis Pathogenesis, Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, United Kingdom
| | - Robert Visse
- From the Arthritis Research UK Centre for Osteoarthritis Pathogenesis, Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, United Kingdom
| | - Deendayal Dinakarpandian
- the School of Computing and Engineering, University of Missouri, Kansas City, Missouri 64111, and
| | | | - Hideaki Nagase
- From the Arthritis Research UK Centre for Osteoarthritis Pathogenesis, Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, United Kingdom
| | - Linda Troeberg
- From the Arthritis Research UK Centre for Osteoarthritis Pathogenesis, Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, United Kingdom,
| |
Collapse
|
21
|
Hubacek JA. Apolipoprotein A5 fifteen years anniversary: Lessons from genetic epidemiology. Gene 2016; 592:193-199. [PMID: 27496343 DOI: 10.1016/j.gene.2016.07.070] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 07/14/2016] [Accepted: 07/31/2016] [Indexed: 02/07/2023]
Abstract
Apolipoprotein A5 (APOA5) is a small protein, expressed predominantly in the liver. In plasma, it is located on triglyceride rich lipoprotein particles (chylomicrones and VLDL) and on HDL. Plasma concentration of apolipoprotein A5 is very low, suggesting rather regulatory (activation of lipoprotein lipase, …) than structural function. APOA5 is an important determinant of plasma triglyceride concentration; this effect has been confirmed both on animal models, as well as on human studies. Minor alleles of three commonly analysed variants within this gene (rs662799, rs3135506, rs2075291) are associated with higher plasma TG values and increased risk of myocardial infarction, with some important interethnic differences observed. Further roles of APOA5; determination of BMI, diabetes and last but not least nutri- and pharmaco-genetic interactions are suggested, but without the definitive conclusions.
Collapse
Affiliation(s)
- Jaroslav A Hubacek
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
| |
Collapse
|
22
|
Mahrooz A, Zargari M, Ansari V, Makhlough A, Hashemi-Sooteh MB. Association of APOA5 Gene Promoter Region -1131T>C Polymorphism (rs662799) to Plasma Triglyceride Level in Patients with Type 2 Diabetic Nephropathy. J Clin Diagn Res 2016; 10:BC09-13. [PMID: 27437205 DOI: 10.7860/jcdr/2016/19212.7895] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 03/18/2016] [Indexed: 01/22/2023]
Abstract
INTRODUCTION Diabetic Nephropathy (DN), a serious complication of Type 2 Diabetic Mellitus (T2DM), is progressive and susceptibility to DN varies among T2DM patients. ApoA5-1131T>C polymorphism revealed that is strongly associated with triglyceride levels and proposed as a predisposing factor for DN. AIM The purpose of this study was to investigate the association -1131T>C ApoA5 gene polymorphism with serum lipids levels in Type 2 diabetic (DM) patients with or without DN in north of Iran (Mazandaran province). MATERIALS AND METHODS This study comprised patients with established T2DM (n=161) and controls (n=58). Genotyping of APOA5 -1131T>C polymorphisms was performed by PCR-RFLP. Diabetic patients were divided into two groups: with nephropathy (DN+, n = 90) and without nephropathy (DN-, n = 71). Lipids and lipoproteins were assessed by enzymatic methods. RESULTS The genotype frequencies were 63.8 % TT, 31 % TC, 5.2 % CC in controls, 33.8% TT, 52.1 % TC, 14.1 % CC in DN- and 44.4 % TT, 36.7 % TC, 18.9 % CC in DN+ patients. The TC genotype and the CC genotype were overexpressed among DN+ and DN-population in comparison to the control group. The highest and the lowest TG levels in both diabetic patients and controls belonged to CC+TC and TT genotypes, respectively. Furthermore in both patients TG increased with this order: TT< TC<CC. CONCLUSION These results suggest that APOA5 -1131T>C polymorphisms influence lipid levels in type 2 diabetic patients.
Collapse
Affiliation(s)
- Abdolkarim Mahrooz
- Faculty of Medicine, Department of Biochemistry, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences , Sari, Iran
| | - Mehryar Zargari
- Faculty of Medicine, Department of Biochemistry, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences , Sari, Iran
| | - Vahid Ansari
- Faculty of Medicine, Department of Biochemistry, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences , Sari, Iran
| | - Atieh Makhlough
- Faculty, Department of Nephrology, Imam Khomeini Hospital, Mazandaran University of Medical Sciences , Sari, IR Iran
| | - Mohammad-Bagher Hashemi-Sooteh
- Faculty of Medicine, Department of Biochemistry, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences , Sari, Iran
| |
Collapse
|
23
|
Schmidt V, Schulz N, Yan X, Schürmann A, Kempa S, Kern M, Blüher M, Poy MN, Olivecrona G, Willnow TE. SORLA facilitates insulin receptor signaling in adipocytes and exacerbates obesity. J Clin Invest 2016; 126:2706-20. [PMID: 27322061 DOI: 10.1172/jci84708] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 04/29/2016] [Indexed: 12/22/2022] Open
Abstract
In humans, genetic variation of sortilin-related receptor, L(DLR class) A repeats containing (SORL1), which encodes the intracellular sorting receptor SORLA, is a major genetic risk factor for familial and sporadic forms of Alzheimer's disease. Recent GWAS analysis has also associated SORL1 with obesity in humans and in mouse models, suggesting that this receptor may play a role in regulating metabolism. Here, using mouse models with genetic loss or tissue-specific overexpression of SORLA as well as data from obese human subjects, we observed a gene-dosage effect that links SORLA expression to obesity and glucose tolerance. Overexpression of human SORLA in murine adipose tissue blocked hydrolysis of triacylglycerides and caused excessive adiposity. In contrast, Sorl1 gene inactivation in mice accelerated breakdown of triacylglycerides in adipocytes and protected animals from diet-induced obesity. We then identified the underlying molecular mechanism whereby SORLA promotes insulin-induced suppression of lipolysis in adipocytes. Specifically, we determined that SORLA acts as a sorting factor for the insulin receptor (IR) that redirects internalized receptor molecules from endosomes to the plasma membrane, thereby enhancing IR surface expression and strengthening insulin signal reception in target cells. Our findings provide a molecular mechanism for the association of SORL1 with human obesity and confirm a genetic link between neurodegeneration and metabolism that converges on the receptor SORLA.
Collapse
|
24
|
Abstract
Apolipoprotein A5 (apoA5) is a potent regulator of triglyceride (TG) metabolism and therefore may contribute to the pathogenesis of non-alcoholic fatty liver disease (NAFLD), a disease characterised by excessive TG-rich lipid droplets in hepatocytes. To test this hypothesis, we examined the mRNA expression of apoA5 in paediatric NAFLD livers in comparison to healthy controls. According to microarray and quantitative real-time PCR, human NAFLD livers exhibited elevated apoA5 expression compared to healthy controls. The apoA5 expression levels were positively correlated with hepatic TG storage and a marker for lipid droplets (perilipin), but were not correlated with plasma TG levels. These observations were confirmed with a NAFLD rat model. Interestingly, apoA5 expression was not altered in cultured fat-laden HepG2 cells, demonstrating that fat storage does not induce apoA5 in NAFLD livers. Therefore, the correlation between apoA5 and intracellular fat storage is likely explained by the potent effect of apoA5 in promoting intracellular fat storage. Our NAFLD patients and rats had elevated insulin resistance, which may have a role in elevating apoA5 expression in NAFLD livers. Our data support the hypothesis that apoA5 promotes hepatic TG storage and therefore contributes to the pathogenesis of NAFLD, and may represent a potential target for therapeutic intervention.
Collapse
|
25
|
Schmidt V, Willnow TE. Protein sorting gone wrong – VPS10P domain receptors in cardiovascular and metabolic diseases. Atherosclerosis 2016; 245:194-9. [DOI: 10.1016/j.atherosclerosis.2015.11.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/04/2015] [Accepted: 11/23/2015] [Indexed: 01/02/2023]
|
26
|
LR11/SorLA links triglyceride-rich lipoproteins to risk of developing cardiovascular disease in FH patients. Atherosclerosis 2015; 243:429-37. [DOI: 10.1016/j.atherosclerosis.2015.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 09/22/2015] [Accepted: 10/05/2015] [Indexed: 12/18/2022]
|
27
|
Forte TM, Sharma V, Ryan RO. Apolipoprotein A-V gene therapy for disease prevention / treatment: a critical analysis. J Biomed Res 2015; 30:88-93. [PMID: 26679785 PMCID: PMC4820885 DOI: 10.7555/jbr.30.20150059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 06/06/2015] [Accepted: 09/05/2015] [Indexed: 12/17/2022] Open
Abstract
Apolipoprotein (apo) A-V is a novel member of the class of exchangeable apo's involved in triacylglycerol (TG) homeostasis. Whereas a portion of hepatic-derived apoA-V is secreted into plasma and functions to facilitate lipoprotein lipase-mediated TG hydrolysis, another portion is recovered intracellularly, in association with cytosolic lipid droplets. Loss of apoA-V function is positively correlated with elevated plasma TG and increased risk of cardiovascular disease. Single nucleotide polymorphisms (SNP) in the APOA5 locus can affect transcription efficiency or introduce deleterious amino acid substitutions. Likewise, rare mutations in APOA5 that compromise functionality are associated with increased plasma TG and premature myocardial infarction. Genetically engineered mouse models and human population studies suggest that, in certain instances, supplementation with wild type (WT) apoA-V may have therapeutic benefit. It is hypothesized that individuals that manifest elevated plasma TG owing to deleterious APOA5 SNPs or rare mutations would respond to WT apoA-V supplementation with improved plasma TG clearance. On the other hand, subjects with hypertriglyceridemia of independent origin (unrelated to apoA-V function) may not respond to apoA-V augmentation in this manner. Improvement in the ability to identify individuals predicted to benefit, advances in gene transfer technology and the strong connection between HTG and heart disease, point to apoA-V supplementation as a viable disease prevention / therapeutic strategy. Candidates would include individuals that manifest chronic TG elevation, have low plasma apoA-V due to an APOA5 mutation/polymorphism and not have deleterious mutations/polymorphisms in other genes known to influence plasma TG levels.
Collapse
Affiliation(s)
- Trudy M Forte
- Center for Prevention of Obesity, Diabetes and Cardiovascular Disease, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - Vineeta Sharma
- Center for Prevention of Obesity, Diabetes and Cardiovascular Disease, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - Robert O Ryan
- Center for Prevention of Obesity, Diabetes and Cardiovascular Disease, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA;
| |
Collapse
|
28
|
Ramasamy I. Recent advances in physiological lipoprotein metabolism. Clin Chem Lab Med 2015; 52:1695-727. [PMID: 23940067 DOI: 10.1515/cclm-2013-0358] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 07/08/2013] [Indexed: 01/21/2023]
Abstract
Research into lipoprotein metabolism has developed because understanding lipoprotein metabolism has important clinical indications. Lipoproteins are risk factors for cardiovascular disease. Recent advances include the identification of factors in the synthesis and secretion of triglyceride rich lipoproteins, chylomicrons (CM) and very low density lipoproteins (VLDL). These included the identification of microsomal transfer protein, the cotranslational targeting of apoproteinB (apoB) for degradation regulated by the availability of lipids, and the characterization of transport vesicles transporting primordial apoB containing particles to the Golgi. The lipase maturation factor 1, glycosylphosphatidylinositol-anchored high density lipoprotein binding protein 1 and an angiopoietin-like protein play a role in lipoprotein lipase (LPL)-mediated hydrolysis of secreted CMs and VLDL so that the right amount of fatty acid is delivered to the right tissue at the right time. Expression of the low density lipoprotein (LDL) receptor is regulated at both transcriptional and post-transcriptional level. Proprotein convertase subtilisin/kexin type 9 (PCSK9) has a pivotal role in the degradation of LDL receptor. Plasma remnant lipoproteins bind to specific receptors in the liver, the LDL receptor, VLDL receptor and LDL receptor-like proteins prior to removal from the plasma. Reverse cholesterol transport occurs when lipid free apoAI recruits cholesterol and phospholipid to assemble high density lipoprotein (HDL) particles. The discovery of ABC transporters (ABCA1 and ABCG1) and scavenger receptor class B type I (SR-BI) provided further information on the biogenesis of HDL. In humans HDL-cholesterol can be returned to the liver either by direct uptake by SR-BI or through cholesteryl ester transfer protein exchange of cholesteryl ester for triglycerides in apoB lipoproteins, followed by hepatic uptake of apoB containing particles. Cholesterol content in cells is regulated by several transcription factors, including the liver X receptor and sterol regulatory element binding protein. This review summarizes recent advances in knowledge of the molecular mechanisms regulating lipoprotein metabolism.
Collapse
|
29
|
Dose apolipoprotein AV has influence on the regulation of fatty acids and triglyceride metabolism in cardiomyocyte in case of obesity. Int J Cardiol 2015; 185:109-11. [PMID: 25791104 DOI: 10.1016/j.ijcard.2015.03.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 03/07/2015] [Indexed: 11/23/2022]
|
30
|
Zhang LS, Xu M, Yang Q, Ryan RO, Howles P, Tso P. Apolipoprotein A-V deficiency enhances chylomicron production in lymph fistula mice. Am J Physiol Gastrointest Liver Physiol 2015; 308:G634-42. [PMID: 25617349 PMCID: PMC4385892 DOI: 10.1152/ajpgi.00339.2014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 01/16/2015] [Indexed: 01/31/2023]
Abstract
Apolipoprotein A-V (apoA-V), a liver-synthesized apolipoprotein discovered in 2001, strongly modulates fasting plasma triglycerides (TG). Little is reported on the effect of apoA-V on postprandial plasma TG, an independent predictor for atherosclerosis. Overexpressing apoA-V in mice suppresses postprandial TG, but mechanisms focus on increased lipolysis or clearance of remnant particles. Unknown is whether apoA-V suppresses the absorption of dietary lipids by the gut. This study examines how apoA-V deficiency affects the steady-state absorption and lymphatic transport of dietary lipids in chow-fed mice. Using apoA-V knockout (KO, n = 8) and wild-type (WT, n = 8) lymph fistula mice, we analyzed the uptake and lymphatic transport of lipids during a continuous infusion of an emulsion containing [(3)H]triolein and [(14)C]cholesterol. ApoA-V KO mice showed a twofold increase in (3)H (P < 0.001) and a threefold increase in (14)C (P < 0.001) transport into the lymph compared with WT. The increased lymphatic transport was accompanied by a twofold reduction (P < 0.05) in mucosal (3)H, suggesting that apoA-V KO mice more rapidly secreted [(3)H]TG out of the mucosa into the lymph. ApoA-V KO mice also produced chylomicrons more rapidly than WT (P < 0.05), as measured by the transit time of [(14)C]oleic acid from the intestinal lumen to lymph. Interestingly, apoA-V KO mice produced a steadily increasing number of chylomicron particles over time, as measured by lymphatic apoB output. The data suggest that apoA-V suppresses the production of chylomicrons, playing a previously unknown role in lipid metabolism that may contribute to the postprandial hypertriglyceridemia associated with apoA-V deficiency.
Collapse
Affiliation(s)
- Linda S. Zhang
- 1Children's Hospital Oakland Research Institute, Oakland, California
| | - Min Xu
- 1Children's Hospital Oakland Research Institute, Oakland, California
| | - Qing Yang
- 1Children's Hospital Oakland Research Institute, Oakland, California
| | - Robert O. Ryan
- 2Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio; and
| | - Philip Howles
- 1Children's Hospital Oakland Research Institute, Oakland, California
| | - Patrick Tso
- 1Children's Hospital Oakland Research Institute, Oakland, California
| |
Collapse
|
31
|
Albers K, Schlein C, Wenner K, Lohse P, Bartelt A, Heeren J, Santer R, Merkel M. Homozygosity for a partial deletion of apoprotein A-V signal peptide results in intracellular missorting of the protein and chylomicronemia in a breast-fed infant. Atherosclerosis 2014; 233:97-103. [DOI: 10.1016/j.atherosclerosis.2013.12.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 11/29/2013] [Accepted: 12/01/2013] [Indexed: 10/25/2022]
|
32
|
Affiliation(s)
- Federico Oldoni
- From the Departments of Molecular Genetics (F.O., J.A.K.) and Genetics (R.J.S.), University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Richard J. Sinke
- From the Departments of Molecular Genetics (F.O., J.A.K.) and Genetics (R.J.S.), University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Jan Albert Kuivenhoven
- From the Departments of Molecular Genetics (F.O., J.A.K.) and Genetics (R.J.S.), University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| |
Collapse
|
33
|
Pieper-Fürst U, Lammert F. Low-density lipoprotein receptors in liver: old acquaintances and a newcomer. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1191-8. [PMID: 24046859 DOI: 10.1016/j.bbalip.2013.03.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The lipoprotein receptors low-density lipoprotein receptor (LDLR), the low-density lipoprotein receptor-related protein 1 (LRP1) and megalin/LRP2 share characteristic structural elements. In addition to their well-known roles in endocytosis of lipoproteins and systemic lipid homeostasis, it has been established that LRP1 mediates the endocytotic clearance of a multitude of extracellular ligands and regulates diverse signaling processes such as growth factor signaling, inflammatory signaling pathways, apoptosis, and phagocytosis in liver. Here, possible functions of LRP1 expression in hepatocytes and non-parenchymal cells in healthy and injured liver are discussed. Recent studies indicate the expression of megalin (LRP2) by hepatic stellate cells, myofibroblasts and Kupffer cells and hypothesize that LRP2 might represent another potential regulator of hepatic inflammatory processes. These observations provide the experimental framework for the systematic and dynamic analysis of the LDLR family during chronic liver injury and fibrogenesis.
Collapse
|
34
|
Li G, Luo H, Sun G, Wu G, Wu G, Wang Y, Man Y, Wang S, Li J, Chen B. Cloning and characterization of a novel apolipoprotein gene, apolipoprotein AV, in tree shrews. Mol Biol Rep 2013; 40:5429-38. [PMID: 23681550 DOI: 10.1007/s11033-013-2641-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 05/03/2013] [Indexed: 01/28/2023]
Abstract
Apolipoprotein AV (apoAV) modulates plasma triglyceride levels, which is an independent risk factor for cardiovascular disease. ApoAV is also involved in atherosclerosis lesion formation. In order to systematically evaluate the apolipoprotein-related gene profile in tree shrew, a model for its insusceptibility to atherosclerosis, we performed apoAV cloning and characterization. The full-length cDNA of apoAV was identified using SMART-RACE. ApoAV cDNA sequence revealed two transcripts, 1,948 and 1,397 base pairs, due to alternative polyadenylation. These two transcripts share the same open reading frame (ORF), which encodes a 369-amino acid protein with high identity to human apoAV (75 %), including a 23-amino acid N-terminal signal peptide. ApoAV is expressed exclusively in the liver. Mature apoAV was expressed in E. coli BL21(DE3) and purified by Ni-chelated resin. Lipoprotein lipase activity was significantly stimulated by this recombinant protein. The full-length ORF of apoAV was cloned into pDsRed-monomer-N1 vector with a red fluorescent protein tag and was primarily localized in cytoplasm of hepG2 cells. The successful cloning, expression and localization of apoAV in tree shrew has laid down the foundation for further investigation on its structure and functions.
Collapse
Affiliation(s)
- Guoping Li
- The Key Laboratory of Geriatrics, Beijing Hospital and Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Mendoza-Barberá E, Julve J, Nilsson SK, Lookene A, Martín-Campos JM, Roig R, Lechuga-Sancho AM, Sloan JH, Fuentes-Prior P, Blanco-Vaca F. Structural and functional analysis of APOA5 mutations identified in patients with severe hypertriglyceridemia. J Lipid Res 2013; 54:649-661. [PMID: 23307945 DOI: 10.1194/jlr.m031195] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
During the diagnosis of three unrelated patients with severe hypertriglyceridemia, three APOA5 mutations [p.(Ser232_Leu235)del, p.Leu253Pro, and p.Asp332ValfsX4] were found without evidence of concomitant LPL, APOC2, or GPIHBP1 mutations. The molecular mechanisms by which APOA5 mutations result in severe hypertriglyceridemia remain poorly understood, and the functional impairment/s induced by these specific mutations was not obvious. Therefore, we performed a thorough structural and functional analysis that included follow-up of patients and their closest relatives, measurement of apoA-V serum concentrations, and sequencing of the APOA5 gene in 200 nonhyperlipidemic controls. Further, we cloned, overexpressed, and purified both wild-type and mutant apoA-V variants and characterized their capacity to activate LPL. The interactions of recombinant wild-type and mutated apoA-V variants with liposomes of different composition, heparin, LRP1, sortilin, and SorLA/LR11 were also analyzed. Finally, to explore the possible structural consequences of these mutations, we developed a three-dimensional model of full-length, lipid-free human apoA-V. A complex, wide array of impairments was found in each of the three mutants, suggesting that the specific residues affected are critical structural determinants for apoA-V function in lipoprotein metabolism and, therefore, that these APOA5 mutations are a direct cause of hypertriglyceridemia.
Collapse
Affiliation(s)
| | - Josep Julve
- Institute for Biomedical Research (IIB) Sant Pau, 08025 Barcelona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas, 08017 Barcelona, Spain
| | - Stefan K Nilsson
- Department of Medical Biosciences/Physiological Chemistry, Umeå University, SE90187, Sweden
| | - Aivar Lookene
- Department of Chemistry, Tallinn Technical University, Tallinn 12618, Estonia
| | | | - Rosa Roig
- Institute for Biomedical Research (IIB) Sant Pau, 08025 Barcelona, Spain
| | | | | | | | - Francisco Blanco-Vaca
- Institute for Biomedical Research (IIB) Sant Pau, 08025 Barcelona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas, 08017 Barcelona, Spain; Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08025 Barcelona, Spain
| |
Collapse
|
36
|
Scilabra SD, Troeberg L, Yamamoto K, Emonard H, Thøgersen I, Enghild JJ, Strickland DK, Nagase H. Differential regulation of extracellular tissue inhibitor of metalloproteinases-3 levels by cell membrane-bound and shed low density lipoprotein receptor-related protein 1. J Biol Chem 2013; 288:332-42. [PMID: 23166318 PMCID: PMC3537031 DOI: 10.1074/jbc.m112.393322] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 10/10/2012] [Indexed: 11/06/2022] Open
Abstract
Tissue inhibitor of metalloproteinases-3 (TIMP-3) plays a key role in regulating extracellular matrix turnover by inhibiting matrix metalloproteinases (MMPs), adamalysins (ADAMs), and adamalysins with thrombospondin motifs (ADAMTSs). We demonstrate that levels of this physiologically important inhibitor can be regulated post-translationally by endocytosis. TIMP-3 was endocytosed and degraded by a number of cell types including chondrocytes, fibroblasts, and monocytes, and we found that the endocytic receptor low density lipoprotein receptor-related protein-1 (LRP-1) plays a major role in TIMP-3 internalization. However, the cellular uptake of TIMP-3 significantly slowed down after 10 h due to shedding of LRP-1 from the cell surface and formation of soluble LRP-1 (sLRP-1)-TIMP-3 complexes. Addition of TIMP-3 to HTB94 human chondrosarcoma cells increased the release of sLRP-1 fragments of 500, 215, 160, and 110 kDa into the medium in a concentration-dependent manner, and all of these fragments were able to bind to TIMP-3. TIMP-3 bound to sLRP-1, which was resistant to endocytosis, retained its inhibitory activity against metalloproteinases. Extracellular levels of sLRP-1 can thus increase the half-life of TIMP-3 in the extracellular space, controlling the bioavailability of TIMP-3 to inhibit metalloproteinases.
Collapse
Affiliation(s)
- Simone D. Scilabra
- From the Department of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
- the Kennedy Institute of Rheumatology, University of Oxford, London W6 8LH, United Kingdom
| | - Linda Troeberg
- From the Department of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
- the Kennedy Institute of Rheumatology, University of Oxford, London W6 8LH, United Kingdom
| | - Kazuhiro Yamamoto
- the Kennedy Institute of Rheumatology, University of Oxford, London W6 8LH, United Kingdom
| | - Hervé Emonard
- the University of Reims Champagne-Ardenne, FRE 3481 CNRS, 51100 Reims, France
| | - Ida Thøgersen
- the Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark, and
| | - Jan J. Enghild
- the Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark, and
| | | | - Hideaki Nagase
- From the Department of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
- the Kennedy Institute of Rheumatology, University of Oxford, London W6 8LH, United Kingdom
| |
Collapse
|
37
|
Zheng XY, Zhao SP, Yan H. The role of apolipoprotein A5 in obesity and the metabolic syndrome. Biol Rev Camb Philos Soc 2012; 88:490-8. [PMID: 23279260 DOI: 10.1111/brv.12005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 11/10/2012] [Accepted: 11/20/2012] [Indexed: 12/17/2022]
Affiliation(s)
- Xiao-Yan Zheng
- Department of Cardiology; The Second Xiangya Hospital, Central South University; Changsha; 410011; China
| | - Shui-Ping Zhao
- Department of Cardiology; The Second Xiangya Hospital, Central South University; Changsha; 410011; China
| | - Hu Yan
- Institute of Mental Health; The Second Xiangya Hospital, Central South University; Changsha; 410011; China
| |
Collapse
|
38
|
Jørgensen AB, Frikke-Schmidt R, West AS, Grande P, Nordestgaard BG, Tybjærg-Hansen A. Genetically elevated non-fasting triglycerides and calculated remnant cholesterol as causal risk factors for myocardial infarction. Eur Heart J 2012; 34:1826-33. [PMID: 23248205 DOI: 10.1093/eurheartj/ehs431] [Citation(s) in RCA: 328] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS Elevated non-fasting triglycerides mark elevated levels of remnant cholesterol. Using a Mendelian randomization approach, we tested whether genetically increased remnant cholesterol in hypertriglyceridaemia due to genetic variation in the apolipoprotein A5 gene (APOA5) associates with an increased risk of myocardial infarction (MI). METHODS AND RESULTS We resequenced the core promoter and coding regions of APOA5 in individuals with the lowest 1% (n = 95) and highest 2% (n = 190) triglyceride levels in the Copenhagen City Heart Study (CCHS, n = 10 391). Genetic variants which differed in frequency between the two extreme triglyceride groups (c.-1131T > C, S19W, and c.*31C > T; P-value: 0.06 to <0.001), thus suggesting an effect on triglyceride levels, were genotyped in the Copenhagen General Population Study (CGPS), the CCHS, and the Copenhagen Ischemic Heart Disease Study (CIHDS), comprising a total of 5705 MI cases and 54 408 controls. Genotype combinations of these common variants associated with increases in non-fasting triglycerides and calculated remnant cholesterol of, respectively, up to 68% (1.10 mmol/L) and 56% (0.40 mmol/L) (P < 0.001), and with a corresponding odds ratio for MI of 1.87 (95% confidence interval: 1.25-2.81). Using APOA5 genotypes in instrumental variable analysis, the observational hazard ratio for a doubling in non-fasting triglycerides was 1.57 (1.32-2.68) compared with a causal genetic odds ratio of 1.94 (1.40-1.85) (P for comparison = 0.28). For calculated remnant cholesterol, the corresponding values were 1.67(1.38-2.02) observational and 2.23(1.48-3.35) causal (P for comparison = 0.21). CONCLUSION These data are consistent with a causal association between elevated levels of remnant cholesterol in hypertriglyceridaemia and an increased risk of MI. Limitations include that remnants were not measured directly, and that APOA5 genetic variants may influence other lipoprotein parameters.
Collapse
Affiliation(s)
- Anders Berg Jørgensen
- Department of Clinical Biochemistry KB3011, Section for Molecular Genetics, Rigshospitalet, Copenhagen University Hospitals and Faculty of Health Sciences, University of Copenhagen, Denmark
| | | | | | | | | | | |
Collapse
|
39
|
Garelnabi M, Lor K, Jin J, Chai F, Santanam N. The paradox of ApoA5 modulation of triglycerides: evidence from clinical and basic research. Clin Biochem 2012; 46:12-9. [PMID: 23000317 DOI: 10.1016/j.clinbiochem.2012.09.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 08/13/2012] [Accepted: 09/10/2012] [Indexed: 01/02/2023]
Abstract
UNLABELLED Apolipoprotein A5 (ApoA5) is a key regulator of plasma triglycerides (TG), even though its plasma concentration is very low compared to other known apoproteins. Over the years, researchers have attempted to elucidate the molecular mechanisms by which ApoA5 regulates plasma TG in vivo. Though still under debate, two theories broadly describe how ApoA5 modulates TG levels: (i) ApoA5 enhances the catabolism of TG-rich lipoproteins and (ii) it inhibits the rate of production of very low-density lipoprotein (VLDL), the major carrier of TGs. This review will summarize the basic and clinical studies that describe the importance of ApoA5 in TG metabolism. Population studies conducted in various countries have demonstrated an association between single nucleotide polymorphisms (SNPs) in ApoA5 and the increased risk to cardiovascular disease and metabolic syndrome (including diabetes and obesity). ApoA5 is also highly expressed during liver regeneration and is an acute phase protein associated with HDL, which is independent of its effects on TG metabolism. CONCLUSION Despite considerable evidences available from clinical and basic research studies on the role of ApoA5 in TG metabolism and its indirect link to metabolic diseases, additional investigations are needed to understand the paradoxical role of this important apoprotein is modulated by both diet and its polymorphism variants.
Collapse
Affiliation(s)
- Mahdi Garelnabi
- Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, MA 01854, USA.
| | | | | | | | | |
Collapse
|
40
|
Liu CF, Yang QF, Chen XL, Liu CY. Apolipoprotein a5 gene polymorphism and risk for metabolic syndrome: a meta-analysis. Genet Test Mol Biomarkers 2012; 16:1241-5. [PMID: 22905904 DOI: 10.1089/gtmb.2012.0183] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
BACKGROUND Many studies have focused on the association between the apolipoprotein A5 (ApoA5) polymorphism and the risk of metabolic syndrome (MetS). However, these studies drew inconsistent conclusions. The aim of this study was to evaluate the exact association between the ApoA5 polymorphism and MetS in a large-scale meta-analysis. METHODS The PubMed, Embase, and Science Citation Index (ISI Web of Science) databases were searched to collect all publications on the association between the ApoA5 polymorphism and MetS. Two common variants of ApoA5 (namely -1131T>C in the promoter region and c.56C>G in the coding region) with the risk of MetS were analyzed. The overall odd ratios (ORs) and 95% confidence intervals (CIs) for -1131T>C (CC+TC) versus TT genotype and c.C56G (GG+GC) versus CC were assessed between the MetS and control group. Subgroup analysis was further performed by ethnicity. The meta-analysis was performed by Stata11.0. RESULTS Twelve studies from 10 publications were chosen in our meta-analysis. The combined results showed that C allele carriers (CC+TC) of -1131T>C had a significantly higher risk of MetS for the overall (OR=1.32; 95% CI: 1.14-1.53; p=0.000) with moderate heterogeneity (I2=54.9%, p=0.014). Subgroup analysis was further performed according to ethnicity, and the association was still significant in Asians (OR=1.42; 95% CI: 1.25-1.62; p=0.000), but not in white populations (OR=1.25; 95% CI: 0.97-1.61; p=0.087). When analyzing the association between c.C56G and MetS, the G allele carrier (GG+GC) genotype significantly increased the risk of MetS (OR=1.32; 95% CI: 1.15-1.50; p=0.000) in white populations. No significant publication bias was observed in either -1131T>C or c.C56G. CONCLUSIONS Our study suggested that the ApoA5 -1131T>C polymorphism was significantly associated with the risk of MetS in Asians, but not in white populations. However, the c.C56G polymorphism was significantly associated with MetS in white populations.
Collapse
Affiliation(s)
- Cun-Fei Liu
- Department of Geriatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | | | | | | |
Collapse
|
41
|
Gordts PL, Bartelt A, Nilsson SK, Annaert W, Christoffersen C, Nielsen LB, Heeren J, Roebroek AJ. Impaired LDL receptor-related protein 1 translocation correlates with improved dyslipidemia and atherosclerosis in apoE-deficient mice. PLoS One 2012; 7:e38330. [PMID: 22701627 PMCID: PMC3368875 DOI: 10.1371/journal.pone.0038330] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 05/03/2012] [Indexed: 01/20/2023] Open
Abstract
Objective Determination of the in vivo significance of LDL receptor-related protein 1 (LRP1) dysfunction on lipid metabolism and atherosclerosis development in absence of its main ligand apoE. Methods and Results LRP1 knock-in mice carrying an inactivating mutation in the NPxYxxL motif were crossed with apoE-deficient mice. In the absence of apoE, relative to LRP1 wild-type animals, LRP1 mutated mice showed an increased clearance of postprandial lipids despite a compromised LRP1 endocytosis rate and inefficient insulin-mediated translocation of the receptor to the plasma membrane, likely due to inefficient slow recycling of the mutated receptor. Postprandial lipoprotein improvement was explained by increased hepatic clearance of triglyceride-rich remnant lipoproteins and accompanied by a compensatory 1.6-fold upregulation of LDLR expression in hepatocytes. One year-old apoE-deficient mice having the dysfunctional LRP1 revealed a 3-fold decrease in spontaneous atherosclerosis development and a 2-fold reduction in LDL-cholesterol levels. Conclusion These findings demonstrate that the NPxYxxL motif in LRP1 is important for insulin-mediated translocation and slow perinuclear endosomal recycling. These LRP1 impairments correlated with reduced atherogenesis and cholesterol levels in apoE-deficient mice, likely via compensatory LDLR upregulation.
Collapse
Affiliation(s)
- Philip L.S.M. Gordts
- Laboratory for Experimental Mouse Genetics, Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Alexander Bartelt
- Department of Biochemistry and Molecular Cell Biology
- Department of Orthopedics University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan K. Nilsson
- Department of Medical Biosciences/Physiological Chemistry, Umeå University, Umeå, Sweden
| | - Wim Annaert
- Laboratory of Membrane Trafficking, Department of Molecular and Developmental Genetics, VIB, Leuven, Belgium
- Laboratory of Membrane Trafficking, Center for Human Genetics, KU Leuven, Leuven, Belgium
| | | | - Lars Bo Nielsen
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology
- * E-mail: (AJMR); (JH)
| | - Anton J.M. Roebroek
- Laboratory for Experimental Mouse Genetics, Center for Human Genetics, KU Leuven, Leuven, Belgium
- * E-mail: (AJMR); (JH)
| |
Collapse
|
42
|
Grosskopf I, Shaish A, Afek A, Shemesh S, Harats D, Kamari Y. Apolipoprotein A-V modulates multiple atherogenic mechanisms in a mouse model of disturbed clearance of triglyceride-rich lipoproteins. Atherosclerosis 2012; 224:75-83. [PMID: 22809445 DOI: 10.1016/j.atherosclerosis.2012.04.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 04/12/2012] [Accepted: 04/16/2012] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Apolipoprotein A-V plays an important role in reducing plasma triglyceride levels. We hypothesized that expression of apoA-V would inhibit atherogenesis in apoE(-/-) mice fed chow diet which is a known model of hypercholesterolemia. Our aim was to study this protective effect and to explore possible mechanisms. METHODS AND RESULTS ApoA-V(+/+)ApoE(-/-) mice expressing human apolipoprotein A-V (hapoA-V) were generated and compared to apoE(-/-) mice. Atherosclerotic aortic sinus lesion area was 70% smaller in hapoA-V(+/+)apoE(-/-). This was accompanied by a 58% reduction in lesion macrophage content. Furthermore, advanced atherosclerotic lesions in hapoA-V(+/+)apoE(-/-) mice showed features of a more stable plaque, manifested by 59% and 37% higher collagen and α-actin content, respectively. Plasma triglyceride and cholesterol levels in hapoA-V(+/+)apoE(-/-) mice were 47% and 33% lower, respectively. These were associated with a 33% reduction in very low density lipoprotein triglyceride production and 2-fold acceleration in triglyceride-rich lipoprotein clearance in hapoA-V(+/+)apoE(-/-) mice. In addition, hapoA-V(+/+)apoE(-/-) mice showed enhanced insulin sensitivity (25% and 15% improvement in glucose tolerance and insulin responsiveness, respectively). Finally, hapoA-V(+/+)apoE(-/-) displayed a milder systemic inflammatory response compared to apoE(-/-) mice, manifested by 22%, 65% and 15% lower plasma levels of TNFα, IL-1β and IL-6, respectively. CONCLUSIONS We showed that human apolipoprotein A-V is a potent modulator of atherosclerosis in mice through multiple modes of action. These findings may identify apoA-V as a potential therapeutic target for treatment of atherosclerosis.
Collapse
Affiliation(s)
- Itamar Grosskopf
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel-Hashomer, Israel.
| | | | | | | | | | | |
Collapse
|
43
|
Sóter MO, Gomes KB, Fernandes AP, Carvalho MDG, Pinheiro PS, Bosco AA, Silva DDR, Sousa MO. -1131T>C and SW19 polymorphisms in APOA5 gene and lipid levels in type 2 diabetic patients. Mol Biol Rep 2012; 39:7541-8. [PMID: 22350263 DOI: 10.1007/s11033-012-1588-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2011] [Accepted: 01/31/2012] [Indexed: 10/28/2022]
Abstract
Type 2 diabetes mellitus is a metabolic, vascular, and neuropathic disease with a high risk of atherosclerotic events due to dyslipidemic states. Polymorphisms in Apolipoprotein A5 gene (APOA5) have been associated with increased triglyceride levels in many different populations. This study aimed to identify the frequencies of the APOA5 -1131T>C and SW19 polymorphisms and evaluate their effects on lipid levels in patients with type 2 diabetes. Genotyping of APOA5 -1131T>C and SW19 polymorphisms was performed by PCR-RFLP in 146 diabetic patients and in controls (n = 173), from 30 to 80 years of age. Diabetic patients were divided into two groups: patients not treated with lipid lowering drugs (group G1; n = 62) and those treated with lipid lowering drugs (group G2, n = 84). Lipids and lipoproteins were determined enzymatically. Among participants not treated with lipid-lowering drugs (diabetics G1 and controls; n = 235), the -1131C was associated with lower LDLc levels (p = 0.015). In the diabetic patients, the 19W allele was associated with higher triglyceride levels (p = 0.004). In G1 diabetic patients, the combined analysis of APOA5 -1131T>C and SW19 polymorphisms showed that [TC or CC] + SS carriers presented lower total cholesterol levels than did other genotype combinations (p = 0.049). It could therefore be concluded that APOA5 -1131T>C and SW19 polymorphisms influence lipid levels in type 2 diabetic patients.
Collapse
Affiliation(s)
- Mirelle O Sóter
- Department of Clinical and Toxicological Analysis, Faculty of Pharmacy, Federal University of Minas Gerais, Antônio Carlos Avenue, 6627 Belo Horizonte, Minas Gerais 31270-901, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Hong CJ, Chen TT, Bai YM, Liou YJ, Tsai SJ. Impact of apolipoprotein A5 (APOA5) polymorphisms on serum triglyceride levels in schizophrenic patients under long-term atypical antipsychotic treatment. World J Biol Psychiatry 2012; 13:22-9. [PMID: 21375366 DOI: 10.3109/15622975.2010.551543] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVES Schizophrenic patients treated with clozapine or olanzapine often develop hypertriglyceridemia. The apolipoprotein A5 gene (APOA5), which affects VLDL production and lipolysis, has been implicated in the triglyceride (TG) metabolism. This study examined the association of common APOA5 genetic variants and TG levels in chronically institutionalized schizophrenic patients, on a stable dose of atypical antipsychotic (clozapine, olanzapine or risperidone. METHODS The TG levels in 466 schizophrenic patients treated with clozapine (n = 182), olanzapine (n = 89) or risperidone (n = 195) were measured. Patients were genotyped for the three APOA5 single nucleotide polymorphisms (SNPs) rs662799 (-1131T > C), rs651821 (3A > G) and rs2266788 (1891T > C). RESULTS A gene × drug interaction with TG levels was observed. In single-marker-based analysis, the minor alleles of the two polymorphisms (-1131C and -3G) were observed to be associated with increased TGs in patients treated with risperidone, but not with clozapine or olanzapine. Haplotype analysis further revealed that carriers of the haplotype constructed with the three minor alleles had higher TG levels than those who did not carry this haplotype in patients taking risperidone (CGC((+/+)) vs. = 125.4 ± 59.1 vs. 82.2 ± 65.8, P = 0.015; CGC((-/+ )) vs. CGC((-/-)) = 113.7 ± 80.4 vs. 82.2 ± 65.8, P = 0.012). CONCLUSIONS Our findings extend and add new information to the existing data regarding the association between APOA5 and TG regulation during long-term atypical antipsychotic treatment.
Collapse
Affiliation(s)
- Chen-Jee Hong
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei
| | | | | | | | | |
Collapse
|
45
|
Sharma V, Ryan RO, Forte TM. Apolipoprotein A-V dependent modulation of plasma triacylglycerol: a puzzlement. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:795-9. [PMID: 22209939 DOI: 10.1016/j.bbalip.2011.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 12/12/2011] [Accepted: 12/13/2011] [Indexed: 02/07/2023]
Abstract
The discovery of apolipoprotein A-V (apoA-V) in 2001 has raised a number of intriguing questions about its role in lipid transport and triglyceride (TG) homeostasis. Genome wide association studies (GWAS) have consistently identified APOA5 as a contributor to plasma TG levels. Single nucleotide polymorphisms (SNP) within the APOA5 gene locus have been shown to correlate with elevated plasma TG. Furthermore, transgenic and knockout mouse models support the view that apoA-V plays a critical role in maintenance of plasma TG levels. The present review describes recent concepts pertaining to apoA-V SNP analysis and their association with elevated plasma TG. The interaction of apoA-V with glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 (GPIHBP1) is discussed relative to its postulated role in TG-rich lipoprotein catabolism. The potential role of intracellular apoA-V in regulation of TG homeostasis, as a function of its ability to associate with cytosolic lipid droplets, is reviewed. While some answers are emerging, numerous mysteries remain with regard to this low abundance, yet potent, modulator of TG homeostasis. Given the strong correlation between elevated plasma TG and heart disease, there is great scientific and public interest in deciphering the numerous biological riddles presented by apoA-V. This article is part of a Special Issue entitled Triglyceride Metabolism and Disease.
Collapse
Affiliation(s)
- Vineeta Sharma
- Center for Prevention of Obesity, Diabetes, and Cardiovascular Disease, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | | | | |
Collapse
|
46
|
Apolipoprotein A-V; a potent triglyceride reducer. Atherosclerosis 2011; 219:15-21. [DOI: 10.1016/j.atherosclerosis.2011.07.019] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 07/03/2011] [Accepted: 07/04/2011] [Indexed: 11/21/2022]
|
47
|
Huang YJ, Lin YL, Chiang CI, Yen CT, Lin SW, Kao JT. Functional importance of apolipoprotein A5 185G in the activation of lipoprotein lipase. Clin Chim Acta 2011; 413:246-50. [PMID: 22008704 DOI: 10.1016/j.cca.2011.09.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 08/12/2011] [Accepted: 09/29/2011] [Indexed: 11/25/2022]
Abstract
BACKGROUND Apolipoprotein A5 (APOA5) over-expression enhances lipolysis of triglyceride (TG) through stimulation of lipoprotein lipase (LPL) activity; however, an APOA5 G185C variant was found associated with hypertriglyceridemia. The aim of this study was, therefore, to explore the importance of APOA5 185GG in the activation of LPL. METHODS A fragment containing mature human APOA5 cDNA was obtained by RT-PCR and subcloned into pET-15b vector. Site-directed mutagenesis was performed to generate 19 variants. Recombinant human APOA5 wild type and variants were produced in Escherichia coli, and then activation of LPL was measured. RESULTS Activity of APOA5 variants on LPL-mediated 1,2-dimyristoyl-sn-glycero-3-phosphocholine hydrolysis was reduced by 17 to 74% in comparison to wild type APOA5 (P<0.0001). All variants also showed reduced activation (P<0.0001) of LPL-mediated hydrolysis of very low-density lipoprotein (VLDL); activation abilities of APOA5 variants ranged from 31 to 81% of wild-type APOA5. CONCLUSIONS APOA5 residue 185G is very important in LPL-mediated VLDL hydrolysis, and any mutation at this residue will decrease LPL activation and concomitant TG modulation.
Collapse
Affiliation(s)
- Yi-Jan Huang
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taiwan
| | | | | | | | | | | |
Collapse
|
48
|
Miller M, Stone NJ, Ballantyne C, Bittner V, Criqui MH, Ginsberg HN, Goldberg AC, Howard WJ, Jacobson MS, Kris-Etherton PM, Lennie TA, Levi M, Mazzone T, Pennathur S. Triglycerides and cardiovascular disease: a scientific statement from the American Heart Association. Circulation 2011; 123:2292-333. [PMID: 21502576 DOI: 10.1161/cir.0b013e3182160726] [Citation(s) in RCA: 1261] [Impact Index Per Article: 97.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
49
|
Zhang X, Chen B. Synthesis of recombinant high density lipoprotein with apolipoprotein A-I and apolipoprotein A-V. Biol Chem 2011; 392:423-9. [PMID: 21476871 DOI: 10.1515/bc.2011.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
It has been shown that apolipoprotein A-V (apoA-V) over-expression significantly lowers plasma triglyceride levels and decreases atherosclerotic lesion development. To assess the feasibility of recombinant high density lipoprotein (rHDL) reconstituted with apoA-V and apolipoprotein A-I (apoA-I) as a therapeutic agent for hyperlipidemic disorder and atherosclerosis, a series of rHDL were synthesized in vitro with various mass ratios of recombinant apoA-I and apoA-V. It is interesting to find that apoA-V of rHDL had no effect on lipoprotein lipase (LPL) activation in vitro and very low density lipoprotein (VLDL) clearance in HepG2 cells and in vivo. By contrast, LPL activation and VLDL clearance were inhibited by the addition of apoA-V to rHDL. Furthermore, the apoA-V of rHDL could not redistribute from rHDL to VLDL after incubation at 37°C for 30 min. These findings suggest that an increase of apoA-V in rHDL could not play a role in VLDL clearance in vitro and in vivo, which could, at least in part, attribute to the lost redistribution of apoA-V from rHDL to VLDL and LPL binding ability of apoA-V in rHDL. The therapeutic application of rHDL reconstituted with apoA-V and apoA-I might need the construction of rHDL from which apoA-V could freely redistribute to VLDL.
Collapse
Affiliation(s)
- Xinbo Zhang
- National Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | | |
Collapse
|
50
|
Abstract
PURPOSE OF REVIEW Sortilins are sorting receptors that direct proteins through secretory and endocytic pathways of the cell. Previously, these receptors have been shown to play important roles in regulating protein transport in neurons and to control neuronal viability and death in many diseases of the nervous system. Recent data, including genome-wide association studies, now suggest equally important functions for sortilins in control of systemic lipoprotein metabolism and risk of cardiovascular disease. This review discusses the evidence implicating two members of this gene family, sortilin and SORLA, in cardiovascular processes. RECENT FINDINGS SORLA is a multifunctional receptor expressed in macrophages and vascular smooth muscle cells. It may act proatherogenic by promoting intimal SMC migration and by regulating apolipoprotein A-V dependent activation of lipoprotein lipase to modulate systemic triglyceride levels. Sortilin, encoded by the cardiovascular risk locus 1p13.3, is a novel regulator of hepatic lipoprotein production. It interacts with apolipoprotein B-100 to control release of very low-density lipoproteins, thereby affecting plasma cholesterol concentrations. SUMMARY Recent data shed light on the importance of sorting receptors in control of cellular and systemic lipoprotein metabolism and how altered trafficking pathways may represent a major risk factor for dyslipidemia and atherosclerosis in the human population.
Collapse
|