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Mormone A, Tortorella G, Esposito F, Caturano A, Marrone A, Cozzolino D, Galiero R, Marfella R, Sasso FC, Rinaldi L. Advances in Pharmacological Approaches for Managing Hypercholesterolemia: A Comprehensive Overview of Novel Treatments. Biomedicines 2024; 12:432. [PMID: 38398034 PMCID: PMC10887105 DOI: 10.3390/biomedicines12020432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Hypercholesterolemia plays a crucial role in the formation of lipid plaques, particularly with elevated low-density lipoprotein (LDL-C) levels, which are linked to increased risks of cardiovascular disease, cerebrovascular disease, and peripheral arterial disease. Controlling blood cholesterol values, specifically reducing LDL-C, is widely recognized as a key modifiable risk factor for decreasing the morbidity and mortality associated with cardiovascular diseases. Historically, statins, by inhibiting the enzyme β-hydroxy β-methylglutaryl-coenzyme A (HMG)-CoA reductase, have been among the most effective drugs. However, newer non-statin agents have since been introduced into hypercholesterolemia therapy, providing a viable alternative with a favorable cost-benefit ratio. This paper aims to delve into the latest therapies, shedding light on their mechanisms of action and therapeutic benefits.
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Affiliation(s)
- Andrea Mormone
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Giovanni Tortorella
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Francesca Esposito
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Alfredo Caturano
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
- Department of Experimental Medicine, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy
| | - Aldo Marrone
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Domenico Cozzolino
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Raffaele Galiero
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Raffaele Marfella
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Ferdinando Carlo Sasso
- Department of Advanced Medical and Surgical Sciences, “Luigi Vanvitelli” University of Campania, 80131 Naples, Italy; (A.M.); (G.T.); (F.E.); (A.C.); (A.M.); (D.C.); (R.G.); (R.M.); (F.C.S.)
| | - Luca Rinaldi
- Department of Medicine and Health Sciences “Vincenzo Tiberio”, Università degli Studi del Molise, 86100 Campobasso, Italy
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Ayoub C, Azar Y, Maddah D, Ghaleb Y, Elbitar S, Abou-Khalil Y, Jambart S, Varret M, Boileau C, El Khoury P, Abifadel M. Low circulating PCSK9 levels in LPL homozygous children with chylomicronemia syndrome in a syrian refugee family in Lebanon. Front Genet 2022; 13:961028. [PMID: 36061186 PMCID: PMC9437297 DOI: 10.3389/fgene.2022.961028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 07/26/2022] [Indexed: 12/17/2022] Open
Abstract
Familial chylomicronemia syndrome is a rare autosomal recessive disorder of lipoprotein metabolism characterized by the presence of chylomicrons in fasting plasma and an important increase in plasma triglycerides (TG) levels that can exceed 22.58 mmol/l. The disease is associated with recurrent episodes of abdominal pain and pancreatitis, eruptive cutaneous xanthomatosis, lipemia retinalis, and hepatosplenomegaly. A consanguineous Syrian family who migrated to Lebanon was referred to our laboratory after perceiving familial chylomicronemia syndrome in two children. The LPL and PCSK9 genes were sequenced and plasma PCSK9 levels were measured. Sanger sequencing of the LPL gene revealed the presence of the p.(Val227Phe) pathogenic variant in exon 5 at the homozygous state in the two affected children, and at the heterozygous state in the other recruited family members. Interestingly, PCSK9 levels in homozygous carriers of the p.(Val227Phe) were ≈50% lower than those in heterozygous carriers of the variant (p-value = 0.13) and ranged between the 5th and the 7.5th percentile of PCSK9 levels in a sample of Lebanese children of approximately the same age group. Moreover, this is the first reported case of individuals carrying simultaneously an LPL pathogenic variant and PCSK9 variants, the L10 and L11 leucine insertion, which can lower and raise low-density lipoprotein cholesterol (LDL-C) levels respectively. TG levels fluctuated concomitantly between the two children, were especially high following the migration from a country to another, and were reduced under a low-fat diet. This case is crucial to raise public awareness on the risks of consanguineous marriages to decrease the emergence of inherited autosomal recessive diseases. It also highlights the importance of the early diagnosis and management of these diseases to prevent serious complications, such as recurrent pancreatitis in the case of familial hyperchylomicronemia.
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Affiliation(s)
- Carine Ayoub
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
| | - Yara Azar
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
| | - Dina Maddah
- Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
| | - Youmna Ghaleb
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
| | - Sandy Elbitar
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
| | - Yara Abou-Khalil
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
| | - Selim Jambart
- Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
| | - Mathilde Varret
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
| | - Catherine Boileau
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
- Genetic Department, AP-HP, Hôpital Bichat, Paris, France
| | - Petra El Khoury
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
| | - Marianne Abifadel
- Laboratory of Biochemistry and Molecular Therapeutics (LBTM), Faculty of Pharmacy, Pôle Technologie- Santé, Saint Joseph University of Beirut, Beirut, Lebanon
- Laboratory for Vascular Translational Science (LVTS), INSERM, Paris Cité University and Sorbonne Paris Nord University, Paris, France
- *Correspondence: Marianne Abifadel,
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Cheng W, He B, Basu S, Souillac P. Identification of Key Excipients for the Solubilization and Structural Characterization of Lipoprotein Lipase, An Enzyme for Hydrolysis of Triglyceride. J Pharm Sci 2021; 110:1958-1968. [PMID: 33516753 DOI: 10.1016/j.xphs.2021.01.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/16/2021] [Accepted: 01/19/2021] [Indexed: 11/17/2022]
Abstract
Lipoprotein lipase (LPL) is an essential enzyme that hydrolyzes triglycerides in chylomicrons and very low-density lipoprotein into glycerol and fatty acids. One major hurdle in using LPL as a therapeutic has been its poor solubility/stability after purification. Solutions used to preserve purified LPL commonly contain either heparin, or concentrated glycerol and sodium chloride, resulting in hypertonic solutions. These solutions are not acceptable as pharmaceutical formulations. This paper describes the identification of a key excipient, sodium laurate, which can solubilize LPL in an isotonic environment without heparin or concentrated glycerol. A follow-up multi-variant study was performed to identify the effect of sodium laurate and its interaction with sodium chloride on the solubility and processing conditions of LPL. The LPL concentration (up to 14 mg/mL) achievable in pharmaceutically relevant and salt-free conditions was identified to be closely correlated to the concentration of sodium laurate, which was co-concentrated with LPL. The result that sodium laurate increases stability of LPL characterized by differential scanning calorimetry and UV absorbance spectra suggests that the mechanism of solubilization of LPL by sodium laurate is related to LPL structural stabilization. The findings indicate that substrates and their enzymatic products can be strong stabilizers for other protein molecules.
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Affiliation(s)
- Weiqiang Cheng
- Drug Product Development-Biologics, Takeda R&D, 200 Shire Way, Lexington, MA 02421, USA.
| | - Bing He
- Drug Product Development-Biologics, Takeda R&D, 200 Shire Way, Lexington, MA 02421, USA
| | - Sujit Basu
- Medical Device Center of Excellence, Takeda R&D, 125 Spring Street, Lexington, MA 02421, USA
| | - Pierre Souillac
- Drug Product Development-Biologics, Takeda R&D, 200 Shire Way, Lexington, MA 02421, USA.
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Dron JS, Wang J, McIntyre AD, Cao H, Robinson JF, Duell PB, Manjoo P, Feng J, Movsesyan I, Malloy MJ, Pullinger CR, Kane JP, Hegele RA. Partial LPL deletions: rare copy-number variants contributing towards severe hypertriglyceridemia. J Lipid Res 2019; 60:1953-1958. [PMID: 31519763 DOI: 10.1194/jlr.p119000335] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 09/09/2019] [Indexed: 01/31/2023] Open
Abstract
Severe hypertriglyceridemia (HTG) is a relatively common form of dyslipidemia with a complex pathophysiology and serious health complications. HTG can develop in the presence of rare genetic factors disrupting genes involved in the triglyceride (TG) metabolic pathway, including large-scale copy-number variants (CNVs). Improvements in next-generation sequencing technologies and bioinformatic analyses have better allowed assessment of CNVs as possible causes of or contributors to severe HTG. We screened targeted sequencing data of 632 patients with severe HTG and identified partial deletions of the LPL gene, encoding the central enzyme involved in the metabolism of TG-rich lipoproteins, in four individuals (0.63%). We confirmed the genomic breakpoints in each patient with Sanger sequencing. Three patients carried an identical heterozygous deletion spanning the 5' untranslated region (UTR) to LPL exon 2, and one patient carried a heterozygous deletion spanning the 5'UTR to LPL exon 1. All four heterozygous CNV carriers were determined to have multifactorial severe HTG. The predicted null nature of our identified LPL deletions may contribute to relatively higher TG levels and a more severe clinical phenotype than other forms of genetic variation associated with the disease, particularly in the polygenic state. The identification of novel CNVs in patients with severe HTG suggests that methods for CNV detection should be included in the diagnostic workup and molecular genetic evaluation of patients with high TG levels.
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Affiliation(s)
- Jacqueline S Dron
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada.,Departments of Biochemistry Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
| | - Jian Wang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
| | - Adam D McIntyre
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
| | - Henian Cao
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
| | - John F Robinson
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
| | - P Barton Duell
- Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR 97239
| | - Priya Manjoo
- Department of Medicine, Gordon and Leslie Diamond Centre, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - James Feng
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94158
| | - Irina Movsesyan
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94158
| | - Mary J Malloy
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94158
| | - Clive R Pullinger
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94158
| | - John P Kane
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94158
| | - Robert A Hegele
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada .,Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada.,Medicine, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
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Abstract
PURPOSE OF REVIEW DNA copy number variations (CNVs) are large-scale mutations that include deletions and duplications larger than 50 bp in size. In the era when single-nucleotide variations were the major focus of genetic technology and research, CNVs were largely overlooked. However, CNVs clearly underlie a substantial proportion of clinical disorders. Here, we update recent progress in identifying CNVs in dyslipidemias. RECENT FINDINGS Until last year, only the LDLR and LPA genes were appreciated as loci within which clinically relevant CNVs contributed to familial hypercholesterolemia and variation in Lp(a) levels, respectively. Since 2017, next-generation sequencing panels have identified pathogenic CNVs in at least five more genes underlying dyslipidemias, including a PCSK9 whole-gene duplication in familial hypercholesterolemia; LPL, GPIHBP1, and APOC2 deletions in hypertriglyceridemia; and ABCA1 deletions in hypoalphalipoproteinemia. SUMMARY CNVs are an important class of mutation that contribute to the molecular genetic heterogeneity underlying dyslipidemias. Clinical applications of next-generation sequencing technologies need to consider CNVs concurrently with familiar small-scale genetic variation, given the likely implications for improved diagnosis and treatment.
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Affiliation(s)
- Michael A Iacocca
- Robarts Research Institute, and Department of Biochemistry, Schulich School of Medicine and Dentistry
| | - Jacqueline S Dron
- Robarts Research Institute, and Department of Biochemistry, Schulich School of Medicine and Dentistry
| | - Robert A Hegele
- Robarts Research Institute, and Department of Biochemistry, Schulich School of Medicine and Dentistry
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
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Severe hypertriglyceridemia in Japan: Differences in causes and therapeutic responses. J Clin Lipidol 2017; 11:1383-1392. [PMID: 28958672 DOI: 10.1016/j.jacl.2017.08.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 07/27/2017] [Accepted: 08/10/2017] [Indexed: 01/01/2023]
Abstract
BACKGROUND Severe hypertriglyceridemia (>1000 mg/dL) has a variety of causes and frequently leads to life-threating acute pancreatitis. However, the origins of this disorder are unclear for many patients. OBJECTIVE We aimed to characterize the causes of and responses to therapy in rare cases of severe hypertriglyceridemia in a group of Japanese patients. METHODS We enrolled 121 patients from a series of case studies that spanned 30 years. Subjects were divided into 3 groups: (1) primary (genetic causes); (2) secondary (acquired); and (3) disorders of uncertain causes. In the last group, we focused on 3 possible risks factors for hypertriglyceridemia: obesity, diabetes mellitus, and heavy alcohol intake. RESULTS Group A (n = 20) included 13 patients with familial lipoprotein lipase deficiency, 3 patients with apolipoprotein CII deficiency, and other genetic disorders in the rest of the group. Group B patients (n = 15) had various metabolic and endocrine diseases. In Group C (uncertain causes; n = 86), there was conspicuous gender imbalance (79 males, 3 females) and most male subjects were heavy alcohol drinkers. In addition, 18 of 105 adult patients (17%) had histories of acute pancreatitis. CONCLUSION The cause of severe hypertriglyceridemia is uncertain in many patients. In primary genetic forms of severe hypertriglyceridemia, genetic diversity between populations is unknown. In the acquired forms, we found fewer cases of estrogen-induced hypertriglyceridemia than in Western countries. In our clinical experience, the cause of most hypertriglyceridemia is uncertain. Our work suggests that genetic factors for plasma triglyceride sensitivity to alcohol should be explored.
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Brunham LR, Hayden MR. Human genetics of HDL: Insight into particle metabolism and function. Prog Lipid Res 2015; 58:14-25. [DOI: 10.1016/j.plipres.2015.01.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 12/22/2014] [Accepted: 01/07/2015] [Indexed: 10/24/2022]
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Grosios K, Petry H, Lubelski J. Adeno-Associated Virus Gene Therapy and Its Application to the Prevention and Personalised Treatment of Rare Diseases. Rare Dis 2015. [DOI: 10.1007/978-94-017-9214-1_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Lipoprotein lipase activity in heterozygotes for lipoprotein lipase gene mutations reveals a gender bias. Ann Clin Biochem 2014; 51:294-7. [DOI: 10.1177/0004563213498711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background Familial lipoprotein lipase (LPL) deficiency is a very rare autosomal recessive disorder characterized by marked elevation of plasma triglyceride concentrations. Since 1989, a variety of mutations have been reported in affected patients. Studies on subjects with heterozygous LPL deficiency, on the other hand, have been limited. Methods We examined post-heparin plasma LPL activity in 15 subjects with heterozygous LPL deficiency. Results The heterozygotes exhibited normal or slightly elevated plasma triglyceride concentrations. The mean LPL activity was reduced by 25% in the heterozygotes relative to controls. Interestingly, LPL activity was reduced specifically in female heterozygotes. Conclusion LPL activity is decreased in female, but not in male, subjects heterozygous for a number of different LPL gene mutations.
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Kastelein JJP, Ross CJD, Hayden MR. From mutation identification to therapy: discovery and origins of the first approved gene therapy in the Western world. Hum Gene Ther 2013; 24:472-8. [PMID: 23578007 DOI: 10.1089/hum.2013.063] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- John J P Kastelein
- Department of Vascular Medicine, Academic Medical Centre, University of Amsterdam, The Netherlands.
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Abstract
Severe hypertriglyceridemia is associated with acute pancreatitis and can be a manifestation of lipoprotein lipase (LPL) deficiency. It is associated with a spectrum of disorders, ranging from heterozygous LPL deficiency allied with environmental factors to rare severe cases of homozygous LPL deficiency. The genes associated with reduced LPL activity include LPL, its cofactor apoC-2, a controlling protein apoA-5 and the LPL receptor GPI-HBP1. The effects of mutations are exacerbated by environmental factors such as diet, pregnancy and insulin resistance. Treatment of clinical LPL deficiency is by ultra-low-fat diet along with the use of fibrates, omega-3 fatty acids, niacin, statins and insulin-sensitizing therapies, depending on the extent of residual LPL activity. Novel therapies that target lipoprotein particle assembly through the antisense oligonucleotides or by interference with triglyceride-loading microsomal transport protein inhibitors offer new potential options for treating hypertriglyceridemia.
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Affiliation(s)
- Adie Viljoen
- Lister Hospital, Stevenage, Hertfordshire, SG1 4AB, UK
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Dubey P, Jayasooriya AP, Cheema SK. Diets Enriched in Fish-Oil or Seal-Oil have Distinct Effects on Lipid Levels and Peroxidation in BioF1B Hamsters. Nutr Metab Insights 2011; 4:7-17. [PMID: 23946657 PMCID: PMC3738469 DOI: 10.4137/nmi.s6728] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aim: Fish-oil omega-3 polyunsaturated fatty acids (n-3 PUFAs) are mostly esterified to the sn-2 position of triglycerides, while in seal-oil triglycerides, these are mostly esterified to the sn-1 and -3 positions. We investigated whether fish-oil and seal-oil feeding has a different effect on the regulation of lipid metabolism and oxidative stress in BioF1B hamsters. Methods: BioF1B hamsters were fed high fat diets rich in fish-oil or seal-oil for 4 weeks, and fasted for 14 hours prior to blood and tissue collection. Results: Plasma and hepatic lipids and lipid peroxidation levels were significantly lower in seal-oil-fed hamsters as compared to those fed fish-oil. There was a selective hindrance of clearance of lipids in fish-oil-fed hamsters as reflected by higher levels of plasma apoB48. Conclusion: Differences in the fatty acid composition and positional distribution of n-3 PUFAs in triglycerides of fish-oil and seal-oil are suggested to trigger metabolic differences.
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Affiliation(s)
- Pratibha Dubey
- Department of Biochemistry, Memorial University, St. John's, NL, A1B 3X9, Canada
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Abstract
Lipoprotein lipase (LPL) is a multifunctional enzyme produced by many tissues, including adipose tissue, cardiac and skeletal muscle, islets, and macrophages. LPL is the rate-limiting enzyme for the hydrolysis of the triglyceride (TG) core of circulating TG-rich lipoproteins, chylomicrons, and very low-density lipoproteins (VLDL). LPL-catalyzed reaction products, fatty acids, and monoacylglycerol are in part taken up by the tissues locally and processed differentially; e.g., they are stored as neutral lipids in adipose tissue, oxidized, or stored in skeletal and cardiac muscle or as cholesteryl ester and TG in macrophages. LPL is regulated at transcriptional, posttranscriptional, and posttranslational levels in a tissue-specific manner. Nutrient states and hormonal levels all have divergent effects on the regulation of LPL, and a variety of proteins that interact with LPL to regulate its tissue-specific activity have also been identified. To examine this divergent regulation further, transgenic and knockout murine models of tissue-specific LPL expression have been developed. Mice with overexpression of LPL in skeletal muscle accumulate TG in muscle, develop insulin resistance, are protected from excessive weight gain, and increase their metabolic rate in the cold. Mice with LPL deletion in skeletal muscle have reduced TG accumulation and increased insulin action on glucose transport in muscle. Ultimately, this leads to increased lipid partitioning to other tissues, insulin resistance, and obesity. Mice with LPL deletion in the heart develop hypertriglyceridemia and cardiac dysfunction. The fact that the heart depends increasingly on glucose implies that free fatty acids are not a sufficient fuel for optimal cardiac function. Overall, LPL is a fascinating enzyme that contributes in a pronounced way to normal lipoprotein metabolism, tissue-specific substrate delivery and utilization, and the many aspects of obesity and other metabolic disorders that relate to energy balance, insulin action, and body weight regulation.
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Affiliation(s)
- Hong Wang
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado 80045, USA
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Sagoo GS, Tatt I, Salanti G, Butterworth AS, Sarwar N, van Maarle M, Jukema JW, Wiman B, Kastelein JJP, Bennet AM, de Faire U, Danesh J, Higgins JPT. Seven lipoprotein lipase gene polymorphisms, lipid fractions, and coronary disease: a HuGE association review and meta-analysis. Am J Epidemiol 2008; 168:1233-46. [PMID: 18922999 DOI: 10.1093/aje/kwn235] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Lipoprotein lipase (LPL) is a key enzyme in lipoprotein metabolism and a major candidate gene for coronary heart disease (CHD). The authors assessed associations between 7 LPL polymorphisms and lipid fractions and CHD risk in population-based cohort, case-control, and cross-sectional studies published by January 2007. Meta-analyses of 22,734 CHD cases and 50,177 controls in 89 association studies focused on the relations of the T-93G (rs1800590), D9N (rs1801177), G188E, N291S (rs268), PvuII (rs285), HindIII (rs320), and S447X (rs328) polymorphisms to high density lipoprotein cholesterol, triglycerides, myocardial infarction, or coronary stenosis. Carriers of 9N or 291S had modestly adverse lipid profiles. Carriers of the less common allele of HindIII or of 447X had modestly advantageous profiles. The combined odds ratio for CHD among carriers was 1.33 (95% confidence interval (CI): 1.14, 1.56) for 9N, 1.07 (95% CI: 0.96, 1.20) for 291S, 0.89 (95% CI: 0.81, 0.98) for the less common HindIII allele, and 0.84 (95% CI: 0.75, 0.94) for 447X. For T-93G (odds ratio (OR) = 1.22, 95% CI: 0.98, 1.52) and PvuII (OR = 0.96, 95% CI: 0.89, 1.04), there were null associations with lipid levels or CHD risk; information on G188E was limited (OR = 2.80, 95% CI: 0.88, 8.87). The study of LPL genotypes confirms the existence of close interrelations between high density lipoprotein cholesterol and triglyceride pathways. The influence of these genotypes on CHD risk warrants further investigation.
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Affiliation(s)
- Gurdeep S Sagoo
- United Kingdom HuGENet Coordinating Centre, Strangeways Research Laboratory, Cambridge, United Kingdom
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Cheema SK, Cornish ML. Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism. Nutr Metab (Lond) 2007; 4:27. [PMID: 18070363 PMCID: PMC2235869 DOI: 10.1186/1743-7075-4-27] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Accepted: 12/10/2007] [Indexed: 11/19/2022] Open
Abstract
Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in lipoprotein lipase activity and mRNA levels contribute to varied response of these hamsters to dietary fat, highlighting the importance of genetic background in the regulation of lipid and lipoprotein metabolism by dietary fats. Bio F1B hamster may prove to be an important animal model to investigate nutrient mediated regulation of metabolic parameters under lipoprotein lipase deficiency.
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Pollex RL, Hegele RA. Genomic copy number variation and its potential role in lipoprotein and metabolic phenotypes. Curr Opin Lipidol 2007; 18:174-80. [PMID: 17353666 DOI: 10.1097/mol.0b013e32802e6c12] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW This review examines the role of copy number variation in the human genome as a newly recognized determinant of lipoprotein and metabolic phenotypes. RECENT FINDINGS Much of the recent progress defining the molecular basis of lipoprotein disorders has been the result of studying genomic DNA at the single nucleotide level, for instance with nucleotide sequence analysis or genotyping to detect single nucleotide polymorphisms. Focus on single nucleotides, however, fails to capture the complete spectrum of potential genetic variability. Recent genome-wide mapping studies have demonstrated the surprising ubiquity of large-scale copy number variations in apparently healthy people, adding to the complexity of the 'normal' genome, but also emphasizing this form of genetic variation as a potential disease mechanism. The application of this understanding to the genetics of lipoprotein disorders has been rapid. For instance, the use of novel techniques to detect copy number variations, such as multiplex ligation-dependent probe amplification, has revealed many additional causative mutations in the low-density lipoprotein receptor gene in patients with familial hypercholesterolemia. SUMMARY Copy number variations thus represent a new level of genomic variation that is both an important mechanism of monogenic lipoprotein disorders and a potential contributor to common complex lipoprotein and metabolic phenotypes in the general population.
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Affiliation(s)
- Rebecca L Pollex
- Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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17
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Chan AOK, But WM, Lau GTC, Tse WY, Shek CC. A novel nonsense mutation in the LPL gene in a Chinese neonate with hypertriglyceridemia. Clin Chim Acta 2006; 368:120-4. [PMID: 16460718 DOI: 10.1016/j.cca.2005.12.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 12/16/2005] [Accepted: 12/16/2005] [Indexed: 11/29/2022]
Abstract
BACKGROUND Lipoprotein lipase (LPL) deficiency is a rare autosomal recessive disorder characterized by hypertriglyceridemia. The genetic defect lies in a mutation of the LPL gene. METHODS A Chinese neonate with non-consanguineous parents was incidentally found to have hypertriglyceridemia. Mutation in her LPL gene was screened by using polymerase chain reaction and direct DNA sequencing. RESULTS Homozygous missense mutations (L252V) were detected in the LPL gene of the patient. A novel nonsense mutation (C27X) was also identified. CONCLUSION Our finding supports L252V mutation in the LPL gene is a common mutation in Chinese with familial hyperchylomicronemia syndrome. DNA-based diagnosis in this syndrome is definitive. It saves the need for heparin-infusion test, which carries the risk of hemorrhage, and the measurement of LPL activity, which is tedious and is not widely available.
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Affiliation(s)
- Angel On-kei Chan
- Department of Pathology, Queen Elizabeth Hospital, Hong Kong, China.
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18
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Schad J, Ganzhorn JU, Sommer S. PARASITE BURDEN AND CONSTITUTION OF MAJOR HISTOCOMPATIBILITY COMPLEX IN THE MALAGASY MOUSE LEMUR, MICROCEBUS MURINUS. Evolution 2005. [DOI: 10.1111/j.0014-3820.2005.tb01002.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Ma YQ, Thomas GN, Critchley JAJH, Lee ZSK, Chan JCN, Tomlinson B. Association of the D8S282 marker near the lipoprotein lipase gene locus with systolic blood pressure in healthy Chinese subjects. J Hypertens 2002; 20:2199-204. [PMID: 12409958 DOI: 10.1097/00004872-200211000-00019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the association between the marker D8S282 near the lipoprotein lipase (LPL) gene locus, and blood pressure, anthropometric and biochemical parameters in 229 healthy Chinese subjects. METHOD Genotyping was performed using an automated DNA sequencer and the Base ImageIR software. Eight different alleles were identified (272-286 bp) resulting in 15 genotypes in our population. We investigated the association between the common (28.8%) 278 bp allele and the anthropometric and biochemical parameters. RESULTS In a tertile analysis, the frequency of the 278 bp allele increased linearly ( P = 0.003) with increasing systolic blood pressure (SBP). The relationship was most evident in the females ( n = 141); SBP was higher in homozygotes for the 278 bp allele (117 +/- 10 mmHg, = 12) than those without this allele (109 +/- 9 mmHg, = 77, 0.05) and was gene-dose dependent, and this difference was more significant after adjusting for age (P = 0.004). No relationship between the locus and the anthropometric or biochemical parameters investigated was observed. CONCLUSION The D8S282 marker near the LPL gene locus contributes to the variance of SBP in healthy Hong Kong Chinese subjects, particularly in females.
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Affiliation(s)
- Yan-Qing Ma
- Department of Medicine and Theraputics. The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR
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20
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Martinez J, Dugaiczyk LJ, Zielinski R, Dugaiczyk A. Human genetic disorders, a phylogenetic perspective. J Mol Biol 2001; 308:587-96. [PMID: 11350162 DOI: 10.1006/jmbi.2001.4755] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
When viewed from the perspective of time, human genetic disorders give new insights into their etiology and evolution. Here, we have correlated a specific set of Alu repetitive DNA elements, known to be the basis of certain genetic defects, with their phylogenetic roots in primate evolution. From a differential distribution of Alu repeats among primate species, we identify the phylogenetic roots of three human genetic diseases involving the LPL, ApoB, and HPRT genes. The different phylogenetic age of these genetic disorders could explain the different susceptibility of various primate species to genetic diseases. Our results show that LPL deficiency is the oldest and should affect humans, apes, and monkeys. ApoB deficiency should affect humans and great apes, while a disorder in the HPRT gene (leading to the Lesch-Nyhan syndrome) is unique to human, chimpanzee, and gorilla. Similar results can be obtained for cancer. We submit that de novo transpositions of Alu elements, and saltatory appearances of Alu-mediated genetic disorders, represent singularities, places where behavior changes suddenly. Alus' propensity to spread, not only increased the regulatory and developmental complexity of the primate genome, it also increased its instability and susceptibility to genetic defects and cancer. The dynamic spread not only provided markers of primate phylogeny, it must have actively shaped the course of that phylogeny.
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Affiliation(s)
- J Martinez
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
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21
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Gilbert B, Rouis M, Griglio S, de Lumley L, Laplaud P. Lipoprotein lipase (LPL) deficiency: a new patient homozygote for the preponderant mutation Gly188Glu in the human LPL gene and review of reported mutations: 75 % are clustered in exons 5 and 6. ANNALES DE GENETIQUE 2001; 44:25-32. [PMID: 11334614 DOI: 10.1016/s0003-3995(01)01037-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We have investigated the lipoprotein lipase (LPL) gene of a 2-year-old patient presenting classical features of the familial LPL deficiency including undetectable LPL activity. DNA sequence analysis of exon 5 identified the patient as a homozygote for the Gly188Glu mutation, frequently involved in this disease. A review of cases of LPL deficiency with molecular study of the LPL gene showed a total number of 221 reported mutations involved in this disease. Gly188Glu was involved in 23.5 % of cases and 74.6 % of mutations were clustered in exons 5 and 6. Based on these observations, we propose a method of screening for mutations in this gene.
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Affiliation(s)
- B Gilbert
- Unité de génétique, hôpital Dupuytren, Limoges, France.
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22
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Mailly F, Palmen J, Muller DP, Gibbs T, Lloyd J, Brunzell J, Durrington P, Mitropoulos K, Betteridge J, Watts G, Lithell H, Angelico F, Humphries SE, Talmud PJ. Familial lipoprotein lipase (LPL) deficiency: a catalogue of LPL gene mutations identified in 20 patients from the UK, Sweden, and Italy. Hum Mutat 2000; 10:465-73. [PMID: 9401010 DOI: 10.1002/(sici)1098-1004(1997)10:6<465::aid-humu8>3.0.co;2-c] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The aim of this study was to identify mutations in the lipoprotein lipase (LPL) gene in 20 unrelated patients with familial lipoprotein deficiency (FLLD) and to investigate the genotype/phenotype relationship. The previously reported G188E mutation (Monsalve et al., J Clin Invest 86:728-734, 1990) was screened for and found to be present in seven individuals (12/40 alleles). In addition, three patients were heterozygous for the 2.0 kb insertion (Langlois et al., Proc Nalt Acad Sci US 86:948-952, 1989). Two approaches were taken for new mutation detection; single-strand conformation polymorphism and sequencing to identify micro-mutations in the proximal promoter and exons 1-9 of the LPL gene and Southern blotting to identify gross mutations. Ten different point mutations were found (W86G, A158T, H183Q, G188E, S193R, P207L, L252X, N291S, M301T, L303P). Additionally, a two nucleotide deletion in exon 6 (delta1006-1007), a six nucleotide deletion in exon 8 (delta1441-1447), and a silent substitution in the wobble position of codon E118 were identified. In vitro mutagenesis and expression in COS-B cells suggested that the A158T and S193R substitutions virtually abolished enzyme activity. In analysing the genotype/phenotype relationship, there was no strong association between age at diagnosis, severity of symptoms, lipid levels, and the nature/position of the mutation. Triglyceride levels, however, were higher in compound heterozygotes compared to true homozygotes, possibly reflecting increased instability of heterodimers. Overall, 29 of 40 (72.5%) mutant alleles were identified. Failure to identify the mutation in 11 alleles might reflect the inadequacy of the method or the possibility that mutations lie within regions of the gene not screened in the study because of lack of availability of sequence.
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Affiliation(s)
- F Mailly
- Department of Medicine, University College London Medical School, UK
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23
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Abstract
This essay addresses the paradoxes of the complex and highly redundant genomes. The central theses developed are that: (1) the distinctive feature of complex genomes is the existence of epigenetic mechanisms that permit extremely high levels of both tandem and dispersed redundancy; (2) the special contribution of transposable elements is to modularize the genome; and (3) the labilizing forces of recombination and transposition are just barely contained, giving a dynamic genetic system of ever increasing complexity that verges on the chaotic.
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Affiliation(s)
- N V Fedoroff
- Biotechnology Institute, Pennsylvania State University, University Park 16802, USA
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24
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Abstract
The chylomicronemia syndrome is a disorder characterized by severe hypertriglyceridemia and fasting chylomicronemia. Genetic causes of the syndrome are rare and include deficiency of lipoprotein lipase (LPL), apolipoprotein C-II, and familial inhibitor of LPL. Patients with familial forms of hypertriglyceridemia in combination with secondary acquired disorders account for most individuals presenting with chylomicronemia. The clinical manifestations--lipid and other biochemical abnormalities--as well as treatment options for chylomicronemic patients are discussed.
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Affiliation(s)
- S Santamarina-Fojo
- Section of Molecular Biology, Molecular Disease Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
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25
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Murano T, Miyashita Y, Itoh Y, Tsuzuki S, Yamamori S, Watanabe H, Shirai K. Incidence of lipoprotein lipase genotype for premature termination codon (Ser447-Ter) in Japanese, and association with dyslipoproteinemia. Clin Chim Acta 1998; 275:205-13. [PMID: 9721078 DOI: 10.1016/s0009-8981(98)00084-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- T Murano
- Department of Clinical Laboratory Medicine, Chiba Prefecture, Japan
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26
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Foubert L, De Gennes JL, Benlian P, Truffert J, Miao L, Hayden MR. Compound heterozygosity for frameshift mutations in the gene for lipoprotein lipase in a patient with early-onset chylomicronemia. Hum Mutat 1998; Suppl 1:S141-4. [PMID: 9452069 DOI: 10.1002/humu.1380110148] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- L Foubert
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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27
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Galton DJ, Zhang Q, Cavallero E, Cavanna J, Kay A, Charles A, Braschi S, Perlemuter L, Jacotot B. Lipid transport genes and their relation to the syndrome of insulin resistance. Ann N Y Acad Sci 1997; 827:100-9. [PMID: 9329745 DOI: 10.1111/j.1749-6632.1997.tb51825.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- D J Galton
- Department of Human Metabolism and Genetics, St. Bartholomew's Hospital, London, United Kingdom
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28
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Rouis M, Dugi KA, Previato L, Patterson AP, Brunzell JD, Brewer HB, Santamarina-Fojo S. Therapeutic response to medium-chain triglycerides and omega-3 fatty acids in a patient with the familial chylomicronemia syndrome. Arterioscler Thromb Vasc Biol 1997; 17:1400-6. [PMID: 9261273 DOI: 10.1161/01.atv.17.7.1400] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have studied the underlying molecular defect in a patient presenting with recurrent pancreatitis, hypertriglyceridemia, and virtually undetectable postheparin plasma lipoprotein lipase (LPL) mass and activity, who normalized her triglycerides 3 to 6 months after initiation of either medium-chain triglyceride (MCT) oil or omega-3 fatty acid (omega-3-FA) therapy. After treatment, postheparin plasma LPL activity and mass ranged from 24% to 39% of normal and LPL specific activity was normal (1.0 nmol.ng-1.min-1). On discontinuation of MCT oil or omega-3-FA, plasma triglyceride increased to > 2000 mg/dL. Northern blotting revealed both normal size and abundance of LPL mRNA isolated from adipocytes as well as macrophages. Sequence analysis of the LPL gene, which included all 10 exons, intron-exon splice junctions, and 1.7 kb of the 5'-flanking region, and of LPL cDNA failed to identify any mutations. ApoC-II activity and mass assays revealed the presence of normal levels of a fully functional cofactor as well as the absence of circulating plasma inhibitors of lipase function. In summary, we describe a unique patient presenting with classical features of the familial chylomicronemia syndrome who manifests an unusually beneficial therapeutic response to MCT oil and omega-3-FA therapy. Unlike that in most patients with LPL deficiency, the chylomicronemia in this patient is not caused by a mutation in the structural LPL gene but possibly by a posttranscriptional defect. Thus, a subset of LPL-deficient patients with unique genetic defects respond to therapy by normalizing fasting plasma triglycerides; a therapeutic trial with MCT oil should be considered in all patients presenting with the familial chylomicronemia syndrome.
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Affiliation(s)
- M Rouis
- Molecular Disease Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Md. 20892-1666, USA
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29
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Hokanson JE. Lipoprotein lipase gene variants and risk of coronary disease: a quantitative analysis of population-based studies. INTERNATIONAL JOURNAL OF CLINICAL & LABORATORY RESEARCH 1997; 27:24-34. [PMID: 9144024 DOI: 10.1007/bf02827239] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The purpose of this study is to quantify the magnitude of the association between common variants in the lipoprotein lipase gene and coronary disease, based on published population-based studies. Fourteen studies, representing 15,708 subjects, report allelic distribution for lipoprotein lipase gene variants among coronary disease patients and control subjects. Patient outcomes included clinical coronary disease events and documented coronary disease based on angiography. Allele frequencies are estimated for disease and non-disease groups within each study. A 2 x 2 contingency table is used to compute individual study odds ratios and 95% confidence intervals, relating the presence of the rare allele to disease status. Mantel-Haenszel-stratified analysis of each allelic variant results in a summary odds ratio and 95% confidence interval for the association between each rare allele in the lipoprotein lipase gene and coronary disease. The lipoprotein lipase D9N allele has a summary odds ratio of 1.59 (95% confidence interval 1.03-2.55), indicating a 59% increase in risk of coronary disease for carriers with this allelic variant. The lipoprotein lipase N291S allele showed no association with coronary disease (summary odds ratio 0.93, 95% confidence interval 0.73-1.19). The summary odds ratio for lipoprotein lipase S447Ter allele is 0.81 (95% confidence interval 0.65-1.0), indicating a marginal negative association between this variant and coronary disease. The common lipoprotein lipase Pvu II polymorphism shows no relation to coronary disease (summary odds ratio 0.90, 95% confidence interval 0.80-1.01). The rare allele of the lipoprotein lipase HindIII polymorphism is negatively associated with coronary disease (summary odds ratio 0.84, 95% confidence interval 0.73-0.96). The lipoprotein lipase D9N allele is associated with high levels of triglyceride and low levels of high-density lipoprotein. Similar atherogenic lipid levels are observed in subjects with structural mutations lipoprotein lipase C188E and P207L. Carriers of the S447Ter allele have low levels of triglyceride. The lipoprotein, lipase gene variants which decrease lipoprotein lipase catalytic activity are associated with familial combined hyperlipidemia, but not the elevation of apolipoprotein B seen in this disorder. In conclusion, allelic variants in the lipoprotein lipase gene are associated with altered lipid levels and differential coronary disease risk.
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Affiliation(s)
- J E Hokanson
- Department of Medicine, School of Public Health and Community Medicine, University of Washington, Seattle, USA
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30
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Rouis M, Lohse P, Dugi KA, Lohse P, Beg OU, Ronan R, Talley GD, Brunzell JD, Santamarina-Fojo S. Homozygosity for two point mutations in the lipoprotein lipase (LPL) gene in a patient with familial LPL deficiency: LPL(Asp9–>Asn, Tyr262–>His). J Lipid Res 1996. [DOI: 10.1016/s0022-2275(20)37606-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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31
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Bijvoet S, Gagné SE, Moorjani S, Gagné C, Henderson HE, Fruchart JC, Dallongeville J, Alaupovic P, Prins M, Kastelein JJ, Hayden MR. Alterations in plasma lipoproteins and apolipoproteins before the age of 40 in heterozygotes for lipoprotein lipase deficiency. J Lipid Res 1996. [DOI: 10.1016/s0022-2275(20)37605-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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32
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Bagdade JD, Ritter MC, Lithell H, Bassett D, Mailly F, Talmud P, Hayden MR. Reduced cholesteryl ester transfer in plasma of patients with lipoprotein lipase deficiency. J Lipid Res 1996. [DOI: 10.1016/s0022-2275(20)39112-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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33
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Benlian P, Etienne J, de Gennes JL, Noé L, Brault D, Raisonnier A, Arnault F, Hamelin J, Foubert L, Chuat JC. Homozygous deletion of exon 9 causes lipoprotein lipase deficiency: possible intron-Alu recombination. J Lipid Res 1995. [DOI: 10.1016/s0022-2275(20)39913-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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34
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Gagné E, Genest J, Zhang H, Clarke LA, Hayden MR. Analysis of DNA changes in the LPL gene in patients with familial combined hyperlipidemia. ARTERIOSCLEROSIS AND THROMBOSIS : A JOURNAL OF VASCULAR BIOLOGY 1994; 14:1250-7. [PMID: 8049185 DOI: 10.1161/01.atv.14.8.1250] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Familial combined hyperlipidemia (FCHL) is a common lipid disorder characterized by an increase in cholesterol and/or triglyceride levels in multiple individuals of the same family. Prior reports document a decreased activity of lipoprotein lipase (LPL) in FCHL, and studies of the role of LPL in the remodeling of nascent lipoproteins suggest that disturbances in LPL function could underlie FCHL. We studied the LPL gene in 31 unrelated individuals with FCHL. A total of 25 DNA changes (13 "silent" substitutions and 12 DNA changes resulting in amino acid substitutions) were detected in 16 patients. Three new exonic polymorphisms as well as a previously described Ser447-->stop and an Asp9-->Asn substitution were seen with similar frequency on control and FCHL chromosomes. Two novel DNA changes resulting in an Asp21-->Val and an His44-->Tyr substitution were seen in only two FCHL individuals. In vitro studies showed no effect of these mutations on LPL catalytic activity. LPL mutations impairing catalytic activity did not represent a significant factor leading to FCHL in this population. Variations in any portion of the coding region of the LPL gene affecting other functions besides catalysis are not a frequent cause of FCHL.
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Affiliation(s)
- E Gagné
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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35
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Nevin DN, Brunzell JD, Deeb SS. The LPL gene in individuals with familial combined hyperlipidemia and decreased LPL activity. ARTERIOSCLEROSIS AND THROMBOSIS : A JOURNAL OF VASCULAR BIOLOGY 1994; 14:869-73. [PMID: 8199176 DOI: 10.1161/01.atv.14.6.869] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Familial combined hyperlipidemia (FCHL) is an oligogenic disorder, with family members having elevated apolipoprotein B-100 levels and either elevated plasma cholesterol or triglyceride levels or both. Obligate heterozygous parents of children with lipoprotein lipase (LPL) deficiency express a mild FCHL phenotype. Of patients with FCHL, 36% have diminished postheparin LPL activity and mass values that are comparable with those of obligate heterozygotes for LPL deficiency. It is hypothesized that heterozygosity for mutations in the LPL gene could contribute to FCHL in this subset of patients. Single-strand conformation polymorphism (SSCP) analysis, direct DNA sequencing, and Southern blot analysis were used to examine exons 1 through 9 and exon-intron junctions of the LPL gene in 20 patients with FCHL and low LPL activity and mass. One subject had a substitution (GAC-->AAC) in exon 2, changing Asp9 to Asn. Two subjects had a previously undescribed "silent" substitution (GTG-->GTA) in exon 3 at Val108. Three patients had a premature termination at codon 447 in exon 9 resulting in truncation of the mature protein by two amino acids. In addition to SSCP analysis, exons 4, 5, and 6, where almost all mutations in LPL-deficient patients have been found, were sequenced and no additional mutations were found. Southern blot analysis of the LPL gene revealed one subject with heterozygous loss of an EcoRI site but without an abnormality in Stu I restriction fragments; this mutation is therefore unlikely to be functionally significant. The substitutions identified at codons 9 and 447 have previously been found not to affect lipolytic activity when expressed in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- D N Nevin
- Department of Medicine, University of Washington, Seattle 98195
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36
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37
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Bruin T, Tuzgöl S, van Diermen DE, Hoogerbrugge-van der Linden N, Brunzell JD, Hayden MR, Kastelein JJ. Recurrent pancreatitis and chylomicronemia in an extended Dutch kindred is caused by a Gly154–>Ser substitution in lipoprotein lipase. J Lipid Res 1993. [DOI: 10.1016/s0022-2275(20)35352-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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38
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Robinson A. No prescription for despair. CMAJ 1993; 149:639-43. [PMID: 8364820 PMCID: PMC1485986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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39
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Overexpression of human lipoprotein lipase in transgenic mice. Resistance to diet-induced hypertriglyceridemia and hypercholesterolemia. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(17)46793-7] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Zannis VI, Kardassis D, Zanni EE. Genetic mutations affecting human lipoproteins, their receptors, and their enzymes. ADVANCES IN HUMAN GENETICS 1993; 21:145-319. [PMID: 8391199 DOI: 10.1007/978-1-4615-3010-7_3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- V I Zannis
- Department of Medicine, Housman Medical Research Center, Boston University Medical Center, Massachusetts 02118
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41
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Reina M, Brunzell JD, Deeb SS. Molecular basis of familial chylomicronemia: mutations in the lipoprotein lipase and apolipoprotein C-II genes. J Lipid Res 1992. [DOI: 10.1016/s0022-2275(20)41340-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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42
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Bruin T, Kastelein JJ, Van Diermen DE, Ma Y, Henderson HE, Stuyt PM, Stalenhoef AF, Sturk A, Brunzell JD, Hayden MR. A missense mutation Pro157 Arg in lipoprotein lipase (LPLNijmegen) resulting in loss of catalytic activity. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 208:267-72. [PMID: 1521525 DOI: 10.1111/j.1432-1033.1992.tb17182.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Here we report on the molecular defect that leads to a deficiency of lipoprotein lipase (LPL) activity in a proband of Dutch descent. Southern-blot analysis of the LPL gene from the patient did not reveal any major DNA rearrangements. Sequencing of polymerase-chain-reaction-amplified DNA revealed that the proband is a homozygote for G725C, resulting in a substitution of Pro157 for Arg. This substitution alters a restriction site for PvuII, which allowed rapid identification of the mutant allele in family members. Site-directed mutagenesis and transient expression of the mutant LPL in COS cells produced an enzymatically inactive protein, establishing the functional significance of this mutation. This naturally occurring mutation which alters the Pro157 adjacent to Asp156 of the proposed catalytic triad, indicates that this region of the protein is indeed crucial for LPL catalytic activity.
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Affiliation(s)
- T Bruin
- Centre for Hemostasis, Thrombosis, Atherosclerosis and Inflammation Research, University of Amsterdam, The Netherlands
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43
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Abstract
Lipoprotein lipase (LPL) hydrolysis the triglyceride core of circulating chylomicrons and very-low-density lipoprotein, and modulates the levels and lipid composition of low and high density lipoproteins. Worldwide, more than 20 mutations in the LPL gene have been identified in patients with familial LPL deficiency. Most of these mutations are clustered in the region encoded by exons 4, 5 and 6 which forms the proposed catalytic domain of LPL. In French Canadians who have the highest reported frequency for LPL deficiency, three common mutations in the LPL gene have been identified which account for approximately 97% of mutant genes in this group. Simple DNA-based tests for the detection of all these mutations have been developed for the screening for carriers of LPL deficiency. This will facilitate further studies of phenotypic expression in heterozygous carriers and assessment of the risk of atherosclerosis in these individuals.
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Affiliation(s)
- M R Hayden
- Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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44
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Sprecher DL, Kobayashi J, Rymaszewski M, Goldberg IJ, Harris BV, Bellet PS, Ameis D, Yunker RL, Black DM, Stein EA. Trp64—-nonsense mutation in the lipoprotein lipase gene. J Lipid Res 1992. [DOI: 10.1016/s0022-2275(20)41511-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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45
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Stocks J, Thorn JA, Galton DJ. Lipoprotein lipase genotypes for a common premature termination codon mutation detected by PCR-mediated site-directed mutagenesis and restriction digestion. J Lipid Res 1992. [DOI: 10.1016/s0022-2275(20)41510-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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46
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Abstract
Hypertriglyceridaemia, as defined by fasting triglyceride levels of greater than 2.8 mmol l-1, is a prevalent dyslipoproteinaemia in our population. The underlying pathophysiological mechanisms that result in elevations of plasma triglycerides are heterogeneous and, in most cases, incompletely understood. However, in a subset of patients presenting with this lipid disorder, the biochemical and genetic defects that lead to hypertriglyceridaemia have been well characterized. These individuals present with the familial chylomicronaemia syndrome, a rare genetic disorder that is inherited as an autosomal recessive trait, and is characterized by severe fasting hypertriglyceridaemia, massive accumulations of chylomicrons in plasma, and recurrent bouts of pancreatitis. The two major causes of the familial chylomicronaemia syndrome are a deficiency of the enzyme, lipoprotein lipase (LPL), or its cofactor, apolipoprotein (apo) C-II. Together, these two proteins initiate the hydrolysis of triglycerides present in chylomicrons and very low density lipoproteins. In the past decade our understanding of the underlying molecular defects that lead to familial chylomicronaemia has been greatly enhanced by the identification of mutations in the genes for LPL and apoC-II. Characterization of these defects has provided new insights into the structure and function of apoC-II and LPL and established the important role that these two proteins play in normal triglyceride metabolism.
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Affiliation(s)
- S S Fojo
- Molecular Disease Branch, National Heart, Lung and Blood Institute, National Institute of Health, Bethesda, MD
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47
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Fojo SS, Beg O, Dichek H, Brewer HB. The molecular defects in lipoprotein lipase deficient patients. Eur J Epidemiol 1992; 8 Suppl 1:59-63. [PMID: 1505655 DOI: 10.1007/bf00145351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The underlying molecular defects that lead to a deficiency of lipoprotein lipase in two patients from different kindreds presenting with the familial hyperchylomicronemia syndrome have been identified. Sequence analysis of amplified LPL cDNA of the patient from the Bethesda kindred revealed a single point mutation (G to A) at position 781 of the normal gene that resulted in the substitution of an alanine for a threonine at residue 176 and the loss of an SfaN1 site present in the normal LPL gene. Amplification of patient cDNA by the PCR followed by restriction enzyme digestion with SfaN1 established that the patient is a true homozygote for the defect. The proband from the second kindred was found to be a compound heterozygote for two separate allelic mutations, including a T to C transition at nucleotide 836 and a G to A mutation at base 983 that led to the substitution of Ile194 by Thr and Arg243 by His, respectively. Transient expression of the mutant LPL cDNAs from both kindreds in human embryonal kidney-293 cells resulted in the synthesis of enzymatically inactive proteins, establishing the functional significance of the mutations.
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Affiliation(s)
- S S Fojo
- Molecular Disease Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892
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48
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Ishimura-Oka K, Semenkovich CF, Faustinella F, Goldberg IJ, Shachter N, Smith LC, Coleman T, Hide WA, Brown WV, Oka K. A missense (Asp250—-Asn) mutation in the lipoprotein lipase gene in two unrelated families with familial lipoprotein lipase deficiency. J Lipid Res 1992. [DOI: 10.1016/s0022-2275(20)41438-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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49
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Bergeron J, Normand T, Bharucha A, Ven Murthy MR, Julien P, Gagné C, Dionne C, De Braekeleer M, Brun D, Hayden MR. Prevalence, geographical distribution and genealogical investigations of mutation 188 of lipoprotein lipase gene in the French Canadian population of Québec. Clin Genet 1992; 41:206-10. [PMID: 1576758 DOI: 10.1111/j.1399-0004.1992.tb03664.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Familial lipoprotein lipase deficiency (FLD) is of particular interest to the French Canadian population of Québec since the largest concentration of homozygotes and carriers of this genetic disease in the world resides in this area. We have previously described a missense mutation (M-188) in the lipoprotein lipase (LPL) gene which was present in FLD patients belonging to different ancestries, including a number of French Canadians (Monsalve MV et al. J Clin Invest 1990: 86: 728-734). In the present report, we show that this mutation, although found in largest absolute numbers among French Canadians as compared to other groups in the world, accounts for only a small proportion (24%) of all the LPL mutant alleles in this population. The M-188 occurs either in the homozygote state or as a compound heterozygote with another LPL mutation. Analysis of geographic distribution indicates that the M-188 is more prevalent in western Québec, with the highest carrier rate in the Mauricie region. Genealogical reconstruction leads to the recognition of four founders for M-188, all emigrants from France to Québec in the 17th century.
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Affiliation(s)
- J Bergeron
- Department of Biochemistry, Faculty of Medicine, Laval University, Québec, Canada
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50
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Takagi A, Ikeda Y, Tsutsumi Z, Shoji T, Yamamoto A. Molecular studies on primary lipoprotein lipase (LPL) deficiency. One base deletion (G916) in exon 5 of LPL gene causes no detectable LPL protein due to the absence of LPL mRNA transcript. J Clin Invest 1992; 89:581-91. [PMID: 1737848 PMCID: PMC442891 DOI: 10.1172/jci115624] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We have systematically investigated a genetic defect resulting in a primary lipoprotein lipase (LPL) deficiency in a proband TN and his affected brother SN, both manifesting familial hyperchylomicronemia. Neither LPL activity nor immunoreactive LPL mass was detected in postheparin plasma from the two patients. Immunocytochemical and biosynthetic studies on the proband's monocyte-derived macrophages with rabbit anti-human LPL antiserum revealed that no immunochemically detectable LPL protein was found in either the cells or culture medium, whereas LPL having a molecular mass of 61 kD was detected in normal cells. No detectable LPL mRNA was identified from poly(A)+RNA of the proband's macrophages by Northern blot analysis, and grossly visible LPL gene rearrangement was not observed by Southern blot analysis. Sequence analysis of polymerase chain reaction-amplified LPL gene exons detected one base deletion of G (first position of Ala221) at base 916 in exon 5 which leads to a premature termination by a frameshift. This mutation, designated as LPLArita and resulting in the loss of an AluI restriction enzyme site, was newly identified. We further analyzed the LPL gene from the two patients and their family members by digestion with AluI. Both patients were homozygous for LPLArita allele, while their spouses did not have this mutation. As genetically expected, their children were all heterozygous for LPLArita. We conclude that primary LPL deficiency in the proband was caused by a lack of enzyme synthesis due to the absence of LPL mRNA resulting from one base deletion of G in exon 5, and that heterozygous LPLArita deficient subjects show almost half value of control LPL mass.
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Affiliation(s)
- A Takagi
- Department of Etiology and Pathophysiology, National Cardiovascular Center Research Institute, Osaka, Japan
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