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Vergès B, Vantyghem MC, Reznik Y, Duvillard L, Rouland A, Capel E, Vigouroux C. Hypertriglyceridemia Results From an Impaired Catabolism of Triglyceride-Rich Lipoproteins in PLIN1-Related Lipodystrophy. Arterioscler Thromb Vasc Biol 2024; 44:1873-1883. [PMID: 38899472 DOI: 10.1161/atvbaha.124.320774] [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] [Received: 01/25/2024] [Accepted: 06/03/2024] [Indexed: 06/21/2024]
Abstract
BACKGROUND Pathogenic variants in PLIN1-encoding PLIN1 (perilipin-1) are responsible for an autosomal dominant form of familial partial lipodystrophy (FPL) associated with severe insulin resistance, hepatic steatosis, and important hypertriglyceridemia. This study aims to decipher the mechanisms of hypertriglyceridemia associated with PLIN1-related FPL. METHODS We performed an in vivo lipoprotein kinetic study in 6 affected patients compared with 13 healthy controls and 8 patients with type 2 diabetes. Glucose and lipid parameters, including plasma LPL (lipoprotein lipase) mass, were measured. LPL mRNA and protein expression were evaluated in abdominal subcutaneous adipose tissue from patients with 5 PLIN1-mutated FPL and 3 controls. RESULTS Patients with PLIN1-mutated FPL presented with decreased fat mass, insulin resistance, and diabetes (glycated hemoglobin A1c, 6.68±0.70% versus 7.48±1.63% in patients with type 2 diabetes; mean±SD; P=0.27). Their plasma triglycerides were higher (5.96±3.08 mmol/L) than in controls (0.76±0.27 mmol/L; P<0.0001) and patients with type 2 diabetes (2.94±1.46 mmol/L, P=0.006). Compared with controls, patients with PLIN1-related FPL had a significant reduction of the indirect fractional catabolic rate of VLDL (very-low-density lipoprotein)-apoB100 toward IDL (intermediate-density lipoprotein)/LDL (low-density lipoprotein; 1.79±1.38 versus 5.34±2.45 pool/d; P=0.003) and the indirect fractional catabolic rate of IDL-apoB100 toward LDL (2.14±1.44 versus 7.51±4.07 pool/d; P=0.005). VLDL-apoB100 production was not different between patients with PLIN1-related FPL and controls. Compared with patients with type 2 diabetes, patients with PLIN1-related FPL also showed a significant reduction of the catabolism of both VLDL-apoB100 (P=0.031) and IDL-apoB100 (P=0.031). Plasma LPL mass was significantly lower in patients with PLIN1-related FPL than in controls (21.03±10.08 versus 55.76±13.10 ng/mL; P<0.0001), although the LPL protein expression in adipose tissue was similar. VLDL-apoB100 and IDL-apoB100 indirect fractional catabolic rates were negatively correlated with plasma triglycerides and positively correlated with LPL mass. CONCLUSIONS We show that hypertriglyceridemia associated with PLIN1-related FPL results from a marked decrease in the catabolism of triglyceride-rich lipoproteins (VLDL and IDL). This could be due to a pronounced reduction in LPL availability, related to the decreased adipose tissue mass.
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MESH Headings
- Humans
- Male
- Perilipin-1/genetics
- Perilipin-1/metabolism
- Perilipin-1/blood
- Triglycerides/blood
- Hypertriglyceridemia/blood
- Hypertriglyceridemia/genetics
- Female
- Adult
- Middle Aged
- Case-Control Studies
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/complications
- Lipoproteins/blood
- Insulin Resistance
- Lipoprotein Lipase/blood
- Lipoprotein Lipase/metabolism
- Lipoprotein Lipase/genetics
- Lipodystrophy, Familial Partial/genetics
- Lipodystrophy, Familial Partial/blood
- Lipodystrophy, Familial Partial/metabolism
- Mutation
- Blood Glucose/metabolism
- Lipoproteins, VLDL/blood
- Lipoproteins, VLDL/metabolism
- Biomarkers/blood
- Phenotype
- Genetic Predisposition to Disease
- Lipolysis
- RNA, Messenger/metabolism
- RNA, Messenger/genetics
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Affiliation(s)
- Bruno Vergès
- Department of Endocrinology, Diabetology and Metabolic Diseases (B.V., A.R.), University Hospital, Dijon, France
- University of Burgundy, INSERM (Institut national de la santé et de la recherche médicale) CTM (Centre de recherche Translationnelle en Médecine moléculaire) UMR1231, Dijon, France (B.V., L.D., A.R.)
| | - Marie-Christine Vantyghem
- Department of Endocrinology, Diabetology, and Metabolism, University of Lille, CHU (Centre Hospitalier Universitaire) Lille, France (M.C.V.)
- Université Lille, U1190 Translational Research for Diabetes, INSERM, Institut Pasteur de Lille, France (M.C.V.)
| | - Yves Reznik
- Department of Endocrinology, University Hospital, Caen, France (Y.R.)
| | - Laurence Duvillard
- Department of Biochemistry (L.D.), University Hospital, Dijon, France
- University of Burgundy, INSERM (Institut national de la santé et de la recherche médicale) CTM (Centre de recherche Translationnelle en Médecine moléculaire) UMR1231, Dijon, France (B.V., L.D., A.R.)
| | - Alexia Rouland
- Department of Endocrinology, Diabetology and Metabolic Diseases (B.V., A.R.), University Hospital, Dijon, France
- University of Burgundy, INSERM (Institut national de la santé et de la recherche médicale) CTM (Centre de recherche Translationnelle en Médecine moléculaire) UMR1231, Dijon, France (B.V., L.D., A.R.)
| | - Emilie Capel
- Inserm U938, Saint-Antoine Research Centre, Institute of Cardiometabolism and Nutrition, Sorbonne University, Paris, France (E.C., C.V.)
| | - Corinne Vigouroux
- Inserm U938, Saint-Antoine Research Centre, Institute of Cardiometabolism and Nutrition, Sorbonne University, Paris, France (E.C., C.V.)
- Department of Molecular Biology and Genetics (C.V.), Assistance Publique-Hôpitaux de Paris, Saint-Antoine University Hospital, France
- Department of Endocrinology, Diabetology and Reproductive Endocrinology, National Reference Center for Rare Diseases of Insulin Secretion and Insulin Sensitivity (C.V.), Assistance Publique-Hôpitaux de Paris, Saint-Antoine University Hospital, France
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2
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Worthmann A, Ridder J, Piel SYL, Evangelakos I, Musfeldt M, Voß H, O'Farrell M, Fischer AW, Adak S, Sundd M, Siffeti H, Haumann F, Kloth K, Bierhals T, Heine M, Pertzborn P, Pauly M, Scholz JJ, Kundu S, Fuh MM, Neu A, Tödter K, Hempel M, Knippschild U, Semenkovich CF, Schlüter H, Heeren J, Scheja L, Kubisch C, Schlein C. Fatty acid synthesis suppresses dietary polyunsaturated fatty acid use. Nat Commun 2024; 15:45. [PMID: 38167725 PMCID: PMC10762034 DOI: 10.1038/s41467-023-44364-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Abstract
Dietary polyunsaturated fatty acids (PUFA) are increasingly recognized for their health benefits, whereas a high production of endogenous fatty acids - a process called de novo lipogenesis (DNL) - is closely linked to metabolic diseases. Determinants of PUFA incorporation into complex lipids are insufficiently understood and may influence the onset and progression of metabolic diseases. Here we show that fatty acid synthase (FASN), the key enzyme of DNL, critically determines the use of dietary PUFA in mice and humans. Moreover, the combination of FASN inhibition and PUFA-supplementation decreases liver triacylglycerols (TAG) in mice fed with high-fat diet. Mechanistically, FASN inhibition causes higher PUFA uptake via the lysophosphatidylcholine transporter MFSD2A, and a diacylglycerol O-acyltransferase 2 (DGAT2)-dependent incorporation of PUFA into TAG. Overall, the outcome of PUFA supplementation may depend on the degree of endogenous DNL and combining PUFA supplementation and FASN inhibition might be a promising approach to target metabolic disease.
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Affiliation(s)
- Anna Worthmann
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Julius Ridder
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sharlaine Y L Piel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ioannis Evangelakos
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Melina Musfeldt
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Hannah Voß
- Section / Core Facility Mass Spectrometry and Proteomics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marie O'Farrell
- Sagimet Biosciences Inc., 155 Bovet Rd., San Mateo, CA, 94402, USA
| | - Alexander W Fischer
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Sangeeta Adak
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University, St. Louis, MO, USA
| | - Monica Sundd
- National Institute of Immunology, New Delhi, India
| | - Hasibullah Siffeti
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Friederike Haumann
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Katja Kloth
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tatjana Bierhals
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Markus Heine
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Paul Pertzborn
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mira Pauly
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Julia-Josefine Scholz
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Suman Kundu
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021 and Department of Biological Sciences, Birla Institute of Technology and Science Pilani, K K Birla Goa Campus, Goa, 403726, India
| | - Marceline M Fuh
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Axel Neu
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Klaus Tödter
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Maja Hempel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Human Genetics, University Hospital Heidelberg, Im Neuenheimer Feld 440, 69120, Heidelberg, Germany
| | - Uwe Knippschild
- Department of General and Visceral Surgery, University Hospital Ulm, Ulm, Germany
| | - Clay F Semenkovich
- Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University, St. Louis, MO, USA
| | - Hartmut Schlüter
- Section / Core Facility Mass Spectrometry and Proteomics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - 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
| | - Christian Kubisch
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Schlein
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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3
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Michaeloudes C, Christodoulides S, Christodoulou P, Kyriakou TC, Patrikios I, Stephanou A. Variability in the Clinical Effects of the Omega-3 Polyunsaturated Fatty Acids DHA and EPA in Cardiovascular Disease-Possible Causes and Future Considerations. Nutrients 2023; 15:4830. [PMID: 38004225 PMCID: PMC10675410 DOI: 10.3390/nu15224830] [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] [Received: 09/27/2023] [Revised: 11/08/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
Cardiovascular disease (CVD) that includes myocardial infarction and stroke, is the leading cause of mortality worldwide. Atherosclerosis, the primary underlying cause of CVD, can be controlled by pharmacological and dietary interventions, including n-3 polyunsaturated fatty acid (PUFA) supplementation. n-3 PUFA supplementation, primarily consisting of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has shown promise in reducing atherosclerosis by modulating risk factors, including triglyceride levels and vascular inflammation. n-3 PUFAs act by replacing pro-inflammatory fatty acid types in cell membranes and plasma lipids, by regulating transcription factor activity, and by inducing epigenetic changes. EPA and DHA regulate cellular function through shared and differential molecular mechanisms. Large clinical studies on n-3 PUFAs have reported conflicting findings, causing confusion among the public and health professionals. In this review, we discuss important factors leading to these inconsistencies, in the context of atherosclerosis, including clinical study design and the differential effects of EPA and DHA on cell function. We propose steps to improve clinical and basic experimental study design in order to improve supplement composition optimization. Finally, we propose that understanding the factors underlying the poor response to n-3 PUFAs, and the development of molecular biomarkers for predicting response may help towards a more personalized treatment.
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Affiliation(s)
- Charalambos Michaeloudes
- School of Medicine, European University Cyprus, Nicosia 2404, Cyprus; (S.C.); (P.C.); (T.-C.K.); (I.P.); (A.S.)
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4
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West AL, Miles EA, Lillycrop KA, Han L, Napier JA, Calder PC, Burdge GC. Dietary supplementation with seed oil from transgenic Camelina sativa induces similar increments in plasma and erythrocyte DHA and EPA to fish oil in healthy humans. Br J Nutr 2020; 124:922-930. [PMID: 32513312 PMCID: PMC7547888 DOI: 10.1017/s0007114520002044] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/21/2020] [Accepted: 06/02/2020] [Indexed: 01/08/2023]
Abstract
EPA and DHA are required for normal cell function and can also induce health benefits. Oily fish are the main source of EPA and DHA for human consumption. However, food choices and concerns about the sustainability of marine fish stocks limit the effectiveness of dietary recommendations for EPA + DHA intakes. Seed oils from transgenic plants that contain EPA + DHA are a potential alternative source of EPA and DHA. The present study investigated whether dietary supplementation with transgenic Camelina sativa seed oil (CSO) that contained EPA and DHA was as effective as fish oil (FO) in increasing EPA and DHA concentrations when consumed as a dietary supplement in a blinded crossover study. Healthy men and women (n 31; age 53 (range 20-74) years) were randomised to consume 450 mg/d EPA + DHA provided either as either CSO or FO for 8 weeks, followed by 6 weeks washout and then switched to consuming the other test oil. Fasting venous blood samples were collected at the start and end of each supplementation period. Consuming the test oils significantly (P < 0·05) increased EPA and DHA concentrations in plasma TAG, phosphatidylcholine and cholesteryl esters. There were no significant differences between test oils in the increments of EPA and DHA. There was no significant difference between test oils in the increase in the proportion of erythrocyte EPA + DHA (CSO, 12 %; P < 0·0001 and FO, 8 %; P = 0·02). Together, these findings show that consuming CSO is as effective as FO for increasing EPA and DHA concentrations in humans.
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Affiliation(s)
- Annette L. West
- School of Human Development and Health, Faculty of Medicine, University of Southampton, SouthamptonSO16 6YD, UK
| | - Elizabeth A. Miles
- School of Human Development and Health, Faculty of Medicine, University of Southampton, SouthamptonSO16 6YD, UK
| | - Karen A. Lillycrop
- Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, SouthamptonSO17 1BJ, UK
| | - Lihua Han
- Department of Plant Sciences, Rothamsted Research, HarpendenAL5 2JQ, UK
| | | | - Philip C. Calder
- School of Human Development and Health, Faculty of Medicine, University of Southampton, SouthamptonSO16 6YD, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust and University of Southampton, SouthamptonSO16 6YD, UK
| | - Graham C. Burdge
- School of Human Development and Health, Faculty of Medicine, University of Southampton, SouthamptonSO16 6YD, UK
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5
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Khatua B, Trivedi RN, Noel P, Patel K, Singh R, de Oliveira C, Trivedi S, Mishra V, Lowe M, Singh VP. Carboxyl Ester Lipase May Not Mediate Lipotoxic Injury during Severe Acute Pancreatitis. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:1226-1240. [PMID: 30954473 DOI: 10.1016/j.ajpath.2019.02.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/19/2019] [Accepted: 02/21/2019] [Indexed: 12/12/2022]
Abstract
Acute lipolysis of visceral fat or circulating triglycerides may worsen acute pancreatitis (AP)-associated local and systemic injury. The pancreas expresses pancreatic triacylglycerol lipase (PNLIP), pancreatic lipase-related protein 2 (PNLIPRP2), and carboxyl ester lipase (CEL), which may leak into the visceral fat or systemic circulation during pancreatitis. We, thus, aimed to determine the pancreatic lipase(s) regulating lipotoxicity during AP. For this AP, associated fat necrosis was analyzed using Western blot analysis. Bile acid (using liquid chromatography-tandem mass spectrometry) and fatty acid (using gas chromatography) concentrations were measured in human fat necrosis. The fat necrosis milieu was simulated in vitro using glyceryl trilinoleate because linoleic acid is increased in fat necrosis. Bile acid requirements to effectively hydrolyze glyceryl trilinoleate were studied using exogenous or overexpressed lipases. The renal cell line (HEK 293) was used to study lipotoxic injury. Because dual pancreatic lipase knockouts are lethal, exocrine parotid acini lacking lipases were used to verify the results. PNLIP, PNLIPRP2, and CEL were increased in fat necrosis. Although PNLIP and PNLIPRP2 were equipotent in inducing lipolysis and lipotoxic injury, CEL required bile acid concentrations higher than in human fat necrosis. The high bile acid requirements for effective lipolysis make CEL an unlikely mediator of lipotoxic injury in AP. It remains to be explored whether PNLIP or PNLIPRP2 worsens AP severity in vivo.
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Affiliation(s)
| | - Ram N Trivedi
- Department of Medicine, Mayo Clinic, Scottsdale, Arizona
| | - Pawan Noel
- Department of Medicine, Mayo Clinic, Scottsdale, Arizona
| | - Krutika Patel
- Department of Medicine, Mayo Clinic, Scottsdale, Arizona
| | - Ravinder Singh
- Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | | | | | - Vivek Mishra
- Department of Medicine, Mayo Clinic, Scottsdale, Arizona
| | - Mark Lowe
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Vijay P Singh
- Department of Medicine, Mayo Clinic, Scottsdale, Arizona.
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7
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Yanai H, Masui Y, Katsuyama H, Adachi H, Kawaguchi A, Hakoshima M, Waragai Y, Harigae T, Sako A. An Improvement of Cardiovascular Risk Factors by Omega-3 Polyunsaturated Fatty Acids. J Clin Med Res 2018; 10:281-289. [PMID: 29511415 PMCID: PMC5827911 DOI: 10.14740/jocmr3362w] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 02/07/2018] [Indexed: 12/27/2022] Open
Abstract
An epidemiological survey in the Northwest Greenland reported that the Greenlanders have a lower frequency of acute myocardial infarction and diabetes mellitus. The very low incidence of ischemic heart disease in the Greenlanders was explained by consumption of a diet rich in omega-3 polyunsaturated fatty acids (PUFAs). Possible anti-atherothrombotic effects of omega-3 PUFA include an improvement of lipid metabolism such as a reduction of triglyceride and an increase of high-density lipoprotein-cholesterol (HDL-C), and glucose metabolism, anti-platelet activity, anti-inflammatory effects, an improvement of endothelial function and stabilization of atherosclerotic plaque. The present study reviews an improvement of cardiovascular risk factors such as dyslipidemia and diabetes due to consumption of omega-3 PUFA. A sufficient number of studies suggest that omega-3 PUFA supplementation reduces serum triglyceride and increases HDL-cholesterol. The mechanisms for omega-3 PUFA-mediated improvements of lipid metabolism have been partially elucidated. The studies using experimental animals, part of trials in humans, have shown the beneficial effects of omega-3 PUFA on glucose metabolism and insulin sensitivity. The meta-analysis showed that omega-3 PUFA might prevent development of diabetes in part of population. Further studies should be performed to elucidate the association of omega-3 PUFA supplementation with diabetes, in the future.
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Affiliation(s)
- Hidekatsu Yanai
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Yoshinori Masui
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Hisayuki Katsuyama
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Hiroki Adachi
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Akiko Kawaguchi
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Mariko Hakoshima
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Yoko Waragai
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Tadanao Harigae
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
| | - Akahito Sako
- Department of Internal Medicine, National Center for Global Health and Medicine Kohnodai Hospital, Chiba, Japan
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8
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Oscarsson J, Hurt-Camejo E. Omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid and their mechanisms of action on apolipoprotein B-containing lipoproteins in humans: a review. Lipids Health Dis 2017; 16:149. [PMID: 28797250 PMCID: PMC5553798 DOI: 10.1186/s12944-017-0541-3] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 08/02/2017] [Indexed: 11/20/2022] Open
Abstract
Background Epidemiological and genetic studies suggest that elevated triglyceride (TG)-rich lipoprotein levels in the circulation increase the risk of cardiovascular disease. Prescription formulations of omega-3 fatty acids (OM3FAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), reduce plasma TG levels and are approved for the treatment of patients with severe hypertriglyceridemia. Many preclinical studies have investigated the TG-lowering mechanisms of action of OM3FAs, but less is known from clinical studies. Methods We conducted a review, using systematic methodology, of studies in humans assessing the mechanisms of action of EPA and DHA on apolipoprotein B-containing lipoproteins, including TG-rich lipoproteins and low-density lipoproteins (LDLs). A systematic search of PubMed retrieved 55 articles, of which 30 were used in the review; 35 additional arrticles were also included. Results In humans, dietary DHA is retroconverted to EPA, while production of DHA from EPA is not observed. Dietary DHA is preferentially esterified into TGs, while EPA is more evenly esterified into TGs, cholesterol esters and phospholipids. The preferential esterification of DHA into TGs likely explains the higher turnover of DHA than EPA in plasma. The main effects of both EPA and DHA are decreased fasting and postprandial serum TG levels, through reduction of hepatic very-low-density lipoprotein (VLDL)-TG production. The exact mechanism for reduced VLDL production is not clear but does not include retention of lipids in the liver; rather, increased hepatic fatty acid oxidation is likely. The postprandial reduction in TG levels is caused by increased lipoprotein lipase activity and reduced serum VLDL-TG concentrations, resulting in enhanced chylomicron clearance. Overall, no clear differences between the effects of EPA and DHA on TG levels, or on turnover of TG-rich lipoproteins, have been observed. Effects on LDL are complex and may be influenced by genetics, such as APOE genotype. Conclusions EPA and DHA diminish fasting circulating TG levels via reduced production of VLDL. The mechanism of reduced VLDL production does not involve hepatic retention of lipids. Lowered postprandial TG levels are also explained by increased chylomicron clearance. Little is known about the specific cellular and biochemical mechanisms underlying the TG-lowering effects of EPA and DHA in humans.
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Affiliation(s)
- Jan Oscarsson
- AstraZeneca Gothenburg, Pepparedsleden 1, SE-431 83, Mölndal, Sweden.
| | - Eva Hurt-Camejo
- AstraZeneca Gothenburg, Pepparedsleden 1, SE-431 83, Mölndal, Sweden
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9
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AbuMweis S, Jew S, Tayyem R, Agraib L. Eicosapentaenoic acid and docosahexaenoic acid containing supplements modulate risk factors for cardiovascular disease: a meta-analysis of randomised placebo-control human clinical trials. J Hum Nutr Diet 2017; 31:67-84. [PMID: 28675488 DOI: 10.1111/jhn.12493] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Over 200 clinical trials have examined the effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplements on risk factors associated with cardiovascular disease. However, an updated analysis of the evidence is lacking. The aim of the present meta-analysis was to quantify the effect of supplements containing EPA and DHA on risk factors for cardiovascular disease. METHODS An analysis was carried on 171 clinical trials with acceptable quality (Jadad score ≥3) that were identified from a comprehensive electronic search strategy of two databases (Pubmed and Cochrane Library). A random effect model was used to obtain an overall estimate on outcomes of interest. Heterogeneity between trial results was tested for using a standard chi-squared test. RESULTS Compared with control, EPA and DHA supplements produced significant reductions of triglycerides of 0.368 mmol L-1 [95% confidence interval (CI) = -0.427 to -0.309], systolic blood pressure of 2.195 mmHg (95% CI = -3.172 to -1.217), diastolic blood pressure of 1.08 mmHg (95% CI = -1.716 to -0.444), heart rate of 1.37 bpm (95% CI = -2.41 to -0.325) and C-reactive protein of 0.343 mg L-1 (95% CI = -0.454 to -0.232). This analysis indicates an increase in both low-density lipoprotein cholesterol (mean difference = 0.150 mmol L-1 ; 95% CI = 0.058-0.243) and high-density lipoprotein cholesterol (mean difference = 0.039 mmol L-1 ; 95% CI = 0.024-0.054). The triglyceride-lowering effect was dose-dependent. CONCLUSIONS The lipid-lowering, hypotensive, anti-arrhythmic and anti-inflammatory actions of EPA and DHA supplements were confirmed in this analysis of randomised placebo-control blinded clinical trials.
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Affiliation(s)
- S AbuMweis
- Department of Clinical Nutrition and Dietetics, The Hashemite University, Zarqa, Jordan
| | - S Jew
- Richardson Centre for Functional Foods and Nutraceuticals, University of Manitoba, Winnipeg, MB, Canada
| | - R Tayyem
- Department of Nutrition and Food Technology, Faculty of Agriculture, The University of Jordan, Amman, Jordan
| | - L Agraib
- Department of Clinical Nutrition and Dietetics, The Hashemite University, Zarqa, Jordan
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10
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Lee P, Prasad K. Effects of Flaxseed Oil on Serum Lipids and Atherosclerosis in Hypercholesterolemic Rabbits. J Cardiovasc Pharmacol Ther 2016; 8:227-35. [PMID: 14506548 DOI: 10.1177/107424840300800308] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective: Flaxseed oil has very high content of ox-linolenic acid (C18:3n-3, omega-3 [n-3] fatty acid). Based on the usefulness of n-3 fatty acid in fish oil against cardiovascular diseases, flaxseed oil is marketed as a health food. The n-3 fatty acid in flaxseed oil is different than that of fish oil. Indirect evidence suggests that the omega-3 fatty acid in flaxseed oil is not effective in lowering serum lipids and hypercholesterolemic atherosclerosis. The effects of flaxseed oil on serum lipids and hypercholesterolemic atherosclerosis are not known. An investigation, therefore, was made of flaxseed oil on high-cholesterol diet-induced atherosclerosis, serum lipids (triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, risk ratio of total cholesterol to high-density lipoprotein cholesterol), serum and aortic malondialdehyde, an index of levels of reactive oxygen species, aortic chemiluminescence (a measure of antioxidant reserve), and reactive oxygen species-producing activity of white blood cell chemiluminescence in rabbits. Methods: The rabbits were assigned to four groups: Group I, regular diet (control); Group II, 5% flaxseed oil in regular diet; Group III, 0.5% cholesterol diet; Group IV, diet containing 0.5% cholesterol and 5% flaxseed oil. Blood samples were collected before and after 4 and 8 weeks of experimental diets for measurement of serum lipids, serum malondialdehyde, and white blood cell chemiluminescence. At the end of 8 weeks of the experimental diet, aortas were removed for measurement of atherosclerotic plaques, aortic malondialdehyde, and antioxidant reserve. Results: Serum total cholesterol, triglycerides, and low-density and high-density lipoprotein cholesterol, and risk ratio of total cholesterol to high-density lipoprotein cholesterol, were elevated to a similar extent in Groups III and IV compared to Groups I and II. The extent of atherosclerosis in Groups III and IV was similar (56.74% ± 11.14% vs 58.01% ± 10.95%). Groups III and IV both had similar increases in serum and aortic malondialdehyde and antioxidant reserve. Reactive oxygen species-producing activity of white blood cells increased in Group III, and flaxseed oil prevented the cholesterol-induced increase in white blood cell chemiluminescence in Group IV. Conclusion: These results suggest that flaxseed oil does not produce an alteration in serum lipids or in the extent of hypercholesterolemic atherosclerosis; however, it decreases white blood cell chemiluminescence. The ineffectiveness of flaxseed oil was associated with its ineffectiveness in altering the levels of oxidative stress.
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Affiliation(s)
- Paul Lee
- Department of Physiology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Chiesa G, Busnelli M, Manzini S, Parolini C. Nutraceuticals and Bioactive Components from Fish for Dyslipidemia and Cardiovascular Risk Reduction. Mar Drugs 2016; 14:md14060113. [PMID: 27338419 PMCID: PMC4926072 DOI: 10.3390/md14060113] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 05/11/2016] [Accepted: 05/26/2016] [Indexed: 12/12/2022] Open
Abstract
Cardiovascular disease remains the most common health problem in developed countries, and residual risk after implementing all current therapies is still high. Permanent changes in lifestyle may be hard to achieve and people may not always be motivated enough to make the recommended modifications. Emerging research has explored the application of natural food-based strategies in disease management. In recent years, much focus has been placed on the beneficial effects of fish consumption. Many of the positive effects of fish consumption on dyslipidemia and heart diseases have been attributed to n-3 polyunsaturated fatty acids (n-3 PUFAs, i.e., EPA and DHA); however, fish is also an excellent source of protein and, recently, fish protein hydrolysates containing bioactive peptides have shown promising activities for the prevention/management of cardiovascular disease and associated health complications. The present review will focus on n-3 PUFAs and bioactive peptides effects on cardiovascular disease risk factors. Moreover, since considerable controversy exists regarding the association between n-3 PUFAs and major cardiovascular endpoints, we have also reviewed the main clinical trials supporting or not this association.
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Affiliation(s)
- Giulia Chiesa
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, Milano 20133, Italy.
| | - Marco Busnelli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, Milano 20133, Italy.
| | - Stefano Manzini
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, Milano 20133, Italy.
| | - Cinzia Parolini
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, via Balzaretti 9, Milano 20133, Italy.
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Mooradian AD, Haas MJ. The effect of nutritional supplements on serum high-density lipoprotein cholesterol and apolipoprotein A-I. Am J Cardiovasc Drugs 2014; 14:253-74. [PMID: 24604774 DOI: 10.1007/s40256-014-0068-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
One of the factors contributing to the increased risk of developing premature atherosclerosis is low plasma concentrations of high-density lipoprotein (HDL) cholesterol. Multiple potential mechanisms account for the cardioprotective effects of HDL and its main protein apolipoprotein A-I (apo A-I). Diet has an important role in modulating HDL cholesterol level. The widespread use of nutritional supplements may also alter the biology of HDL. In this review, we discuss the effect of select nutritional supplements on serum HDL cholesterol and apo A-I levels. Some nutritional supplements, such as phytosterols, soy proteins, and black seed extracts, may increase HDL cholesterol levels, while others such as cholic acid and high doses of commonly used antioxidant vitamins may downregulate HDL cholesterol levels and reduce its cardioprotection. Multiple mechanisms are involved in the regulation of HDL levels, so changes in production and clearance of HDL may have different clinical implications. The clinical relevance of the changes in HDL and apo A-I caused by nutrient supplementation needs to be tested in controlled clinical trials.
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Affiliation(s)
- Arshag D Mooradian
- Department of Medicine, University of Florida College of Medicine, 653-1 West 8th Street, 4th Floor, LRC, Jacksonville, FL, 32209, USA,
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Effects of eicosapentaenoic acid and docosahexaenoic acid on chylomicron and VLDL synthesis and secretion in Caco-2 cells. BIOMED RESEARCH INTERNATIONAL 2014; 2014:684325. [PMID: 24987699 PMCID: PMC4058467 DOI: 10.1155/2014/684325] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 04/19/2014] [Indexed: 11/18/2022]
Abstract
The present research was undertaken to determine the effects of EPA (20 : 5 n-3) and DHA (22 : 6 n-3) on chylomicron and VLDL synthesis and secretion by Caco-2 cells. Cells were incubated for 12 to 36 h with 400 μM OA, EPA, and DHA; then 36 h was chosen for further study because EPA and DHA decreased de novo triglycerides synthesis in a longer incubation compared with OA (P < 0.01). Neither the uptake nor oxidation was different in response to the respective fatty acids (P > 0.05). Compared with OA, intercellular and secreted nascent apolipoprotein B48 and B100 were decreased by EPA and DHA (P < 0.01). Both DHA and EPA resulted in a lower secretion of chylomicron and VLDL (P < 0.01). In contrast to OA, EPA and DHA were preferentially incorporated into phospholipids instead of triacylglycerols (P < 0.01). These discoveries demonstrated that exposure of DHA and EPA reduced the secretion of chylomicron and VLDL partly by regulating the synthesis of TG and apoB.
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Jones AJ, Grkovic T, Sykes ML, Avery VM. Trypanocidal activity of marine natural products. Mar Drugs 2013; 11:4058-82. [PMID: 24152565 PMCID: PMC3826150 DOI: 10.3390/md11104058] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 10/09/2013] [Accepted: 10/10/2013] [Indexed: 12/21/2022] Open
Abstract
Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion.
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Affiliation(s)
- Amy J Jones
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, Brisbane 4111, Australia.
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15
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Chung KH, Hwang HJ, Shin KO, Jeon WM, Choi KS. Effects of perilla oil on plasma concentrations of cardioprotective (n-3) fatty acids and lipid profiles in mice. Nutr Res Pract 2013; 7:256-61. [PMID: 23964311 PMCID: PMC3746158 DOI: 10.4162/nrp.2013.7.4.256] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 01/27/2013] [Accepted: 03/04/2013] [Indexed: 11/04/2022] Open
Abstract
The aim of this study was to examine the effects of perilla oil as well as several vegetable oils, including flaxseed oil, canola oil, and rice bran oil on plasma levels of cardioprotective (n-3) polyunsaturated fatty acids in mice by feeding each vegetable oil for a period of eight weeks. Concentrations of docosapentaenoic acid (DHA) and eicosapentaenoic acid (EPA), fish-based (n-3) polyunsaturated fatty acids, showed an increase in the plasma of mice fed perilla and flaxseed oils compared to those of mice in the control group (P < 0.05), whereas rice bran and canola oils did not alter plasma DPA and EPA concentrations. Arachidonic acid concentration was increased by feeding rice bran oil (P < 0.05), but not canola, flaxseed, or perilla oil. In addition, oleic acid, linoleic acid, and docosahexaenoic acid concentrations were altered by feeding dietary rice bran, canola, perilla, and flaxseed oils. Findings of this study showed that perilla oil, similar to flaxseed oil, is cardioprotective and could be used as an alternative to fish oil or even flaxseed oil in animal models.
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Affiliation(s)
- Keun Hee Chung
- Department of Food and Nutrition, Sahmyook University, 815, Hwarang-ro, Nowon-gu, Seoul 139-742, Korea
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Echium oil reduces plasma triglycerides by increasing intravascular lipolysis in apoB100-only low density lipoprotein (LDL) receptor knockout mice. Nutrients 2013; 5:2629-45. [PMID: 23857172 PMCID: PMC3738992 DOI: 10.3390/nu5072629] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 06/09/2013] [Accepted: 06/24/2013] [Indexed: 02/06/2023] Open
Abstract
Echium oil (EO), which is enriched in SDA (18:4 n-3), reduces plasma triglyceride (TG) concentrations in humans and mice. We compared mechanisms by which EO and fish oil (FO) reduce plasma TG concentrations in mildly hypertriglyceridemic male apoB100-only LDLrKO mice. Mice were fed one of three atherogenic diets containing 0.2% cholesterol and palm oil (PO; 20%), EO (10% EO + 10% PO), or FO (10% FO + 10% PO). Livers from PO- and EO-fed mice had similar TG and cholesteryl ester (CE) content, which was significantly higher than in FO-fed mice. Plasma TG secretion was reduced in FO vs. EO-fed mice. Plasma very low density lipoprotein (VLDL) particle size was ordered: PO (63 ± 4 nm) > EO (55 ± 3 nm) > FO (40 ± 2 nm). Post-heparin lipolytic activity was similar among groups, but TG hydrolysis by purified lipoprotein lipase was significantly greater for EO and FO VLDL compared to PO VLDL. Removal of VLDL tracer from plasma was marginally faster in EO vs. PO fed mice. Our results suggest that EO reduces plasma TG primarily through increased intravascular lipolysis of TG and VLDL clearance. Finally, EO may substitute for FO to reduce plasma TG concentrations, but not hepatic steatosis in this mouse model.
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Glueck CJ, Khan N, Riaz M, Padda J, Khan Z, Wang P. Titrating lovaza from 4 to 8 to 12 grams/day in patients with primary hypertriglyceridemia who had triglyceride levels >500 mg/dl despite conventional triglyceride lowering therapy. Lipids Health Dis 2012; 11:143. [PMID: 23110706 PMCID: PMC3551656 DOI: 10.1186/1476-511x-11-143] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 10/26/2012] [Indexed: 12/02/2022] Open
Abstract
Background Omega-3 fatty acids are important in treatment of severe primary hypertriglyceridemia (HTG). In 15 patients with severe primary HTG (TG >500 mg/dl despite conventional TG lowering therapy), we assessed efficacy-safety of sequential monthly treatment with Lovaza, 4 to 8 to 12 g/day. Methods With TG >500 mg/dl despite Type V diet, hyperinsulinemia and diabetes control, and fibric acids, Lovaza (4 g/d) was added for 1 month, and if TG remained >500 mg/dl, increased to 8 g/d for 1 month, and then to 12 g/d for 1 month, and subsequently reduced to 4 g/day for 4 months. Results Primary HTG, median TG 884 mg/dl, 14 men, 1 woman, all white, age 50 ± 7 years, 12 non-diabetic, 3 with stable diabetes control. Weight and diet held stable throughout. In 5 patients, after 1, 2, and 3 months on 4 g/day, TG fell <500, mean 1390 to 234 (−83%, p<.0001), to 135 (−90%, p<.0001), and 158 mg/dl (−89%, p<.0001), with a negative TG slope, p=.0013. Non-HDLC fell from 320 to 177 (−45%, p=.001), to 152 (−53%, p=.0002), and to 163 (−49%, p=.0004), with a negative slope, p=.01. In 10 patients, with Lovaza increased from 4 to 8 to 12 g, 3 failed to respond. In 7 of these 10 patients, TG fell 37% from 1075 to 672 on 4 g (p=.006), to 577 on 8 g (−46%, p=.0009), and to 428 mg/dl (−60%, p<.0001) on 12 g/day, with a negative TG slope, p=.0018. TG on 12 g/day was lower than on 8 g/day, p =.03. Non-HDLC fell from 245 to 217 mg/dl (−11%) on 4 g/day, to 203 (−17%, p=.01) on 8 g/day, and to 192 (−22%, p=.003) on 12 g/day, with a negative slope, p=.016. Compared to pre-Lovaza baseline, no abnormal measures developed in safety tests. The 4, 8, and 12 g/d Lovaza doses were well tolerated. Conclusion Titration of Lovaza from 4 to 8 to 12 g/d safely offers an effective way to lower TG beyond conventional 4 g therapy.
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Affiliation(s)
- Charles J Glueck
- Cholesterol Center, Jewish Hospital of Cincinnati, UC Health Building, 3200 Burnet Avenue, Cincinnati, OH 45229, USA.
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Shearer GC, Savinova OV, Harris WS. Fish oil -- how does it reduce plasma triglycerides? Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:843-51. [PMID: 22041134 DOI: 10.1016/j.bbalip.2011.10.011] [Citation(s) in RCA: 183] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 10/07/2011] [Accepted: 10/10/2011] [Indexed: 01/30/2023]
Abstract
Long chain omega-3 fatty acids (FAs) are effective for reducing plasma triglyceride (TG) levels. At the pharmaceutical dose, 3.4g/day, they reduce plasma TG by about 25-50% after one month of treatment, resulting primarily from the decline in hepatic very low density lipoprotein (VLDL-TG) production, and secondarily from the increase in VLDL clearance. Numerous mechanisms have been shown to contribute to the TG overproduction, but a key component is an increase in the availability of FAs in the liver. The liver derives FAs from three sources: diet (delivered via chylomicron remnants), de novo lipogenesis, and circulating non-esterified FAs (NEFAs). Of these, NEFAs contribute the largest fraction to VLDL-TG production in both normotriglyceridemic subjects and hypertriglyceridemic, insulin resistant patients. Thus reducing NEFA delivery to the liver would be a likely locus of action for fish oils (FO). The key regulator of plasma NEFA is intracellular adipocyte lipolysis via hormone sensitive lipase (HSL), which increases as insulin sensitivity worsens. FO counteracts intracellular lipolysis in adipocytes by suppressing adipose tissue inflammation. In addition, FO increases extracellular lipolysis by lipoprotein lipase (LpL) in adipose, heart and skeletal muscle and enhances hepatic and skeletal muscle β-oxidation which contributes to reduced FA delivery to the liver. FO could activate transcription factors which control metabolic pathways in a tissue specific manner regulating nutrient traffic and reducing plasma TG. This article is part of a Special Issue entitled Triglyceride Metabolism and Disease.
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Affiliation(s)
- Gregory C Shearer
- Cardiovascular Health Research Center, Sanford Research USD, SD, USA.
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Simão ANC, Godeny P, Lozovoy MAB, Dichi JB, Dichi I. Efeito dos ácidos graxos n-3 no perfil glicêmico e lipídico, no estresse oxidativo e na capacidade antioxidante total de pacientes com síndrome metabólica. ACTA ACUST UNITED AC 2010; 54:463-9. [DOI: 10.1590/s0004-27302010000500006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 04/24/2010] [Indexed: 11/22/2022]
Abstract
OBJETIVO: A síndrome metabólica (SM) é um conjunto de fatores que favorecem o desenvolvimento de doenças cardiovasculares. Estudos prévios demonstram que os ácidos graxos poliinsaturados (PUFAs) podem melhorar alguns desses fatores. O objetivo foi avaliar o efeito do óleo de peixe rico em PUFAs nos perfis glicêmico e lipídico, no estresse oxidativo e na capacidade antioxidante total (TRAP) no plasma em pacientes com SM. SUJEITOS E MÉTODOS: Foi realizado um ensaio clínico em 40 pacientes com SM (20 controles e 20 pacientes que consumiram 3 g/dia de PUFAs). RESULTADOS: O grupo que recebeu tratamento apresentou redução significativa nos níveis de triacilgliceróis e aumento no TRAP, mas sofreu aumento nos níveis de LDL, glicose e na resistência à insulina. CONCLUSÃO: Conclui-se que a ingestão de óleo de peixe foi capaz de diminuir os níveis de triacilgliceróis e aumentar o TRAP de pacientes com SM, porém verificou-se aumento nos níveis de LDL e na resistência à insulina.
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Tulk HMF, Robinson LE. Modifying the n-6/n-3 polyunsaturated fatty acid ratio of a high-saturated fat challenge does not acutely attenuate postprandial changes in inflammatory markers in men with metabolic syndrome. Metabolism 2009; 58:1709-16. [PMID: 19625064 DOI: 10.1016/j.metabol.2009.05.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 05/20/2009] [Indexed: 01/01/2023]
Abstract
Metabolic syndrome (MetS) features chronic inflammation and exaggerated postprandial triacylglyceride (TAG) responses. Fasting concentrations of interleukin-6 (IL-6) and C-reactive protein (CRP), key inflammatory mediators, decrease after sustained n-3 polyunsaturated fatty acid (PUFA) intake; however, the ability of n-3 PUFA to attenuate postprandial inflammatory responses is not well studied. Thus, we examined the acute effect of modifying the n-6/n-3 PUFA ratio of a high-saturated fatty acid (SFA) oral fat tolerance test (OFTT) on postprandial TAG and inflammatory responses in men with MetS. Men (n = 8, > or = 45 years old) with MetS ingested 2 high-SFA OFTTs (1 g fat per kilogram body weight), with either a 20:1 (low n-3) or 2:1 (high n-3) n-6/n-3 PUFA ratio, and a water control in a randomized crossover design. Blood samples were collected for 8 hours after treatment to measure postprandial TAG, free fatty acids, IL-6, soluble IL-6 receptor, and CRP. Postprandial TAG increased at the same rate after ingestion of the low-n-3 and high-n-3 OFTTs; however, both OFTTs were significantly different from the water control. There were no differences in the rate at which IL-6 concentrations increased after ingestion of either of the OFTTs compared with water. Furthermore, neither time nor treatment affected circulating soluble IL-6 receptor or CRP concentrations. Thus, increasing the n-3 PUFA content of a high-SFA OFTT does not acutely change postprandial TAG or inflammatory responses in men with MetS.
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Affiliation(s)
- Hilary M F Tulk
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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Bell S, Cooney J, Packard CJ, Caslake M, Deighan CJ. Omega-3 fatty acids improve postprandial lipaemia in patients with nephrotic range proteinuria. Atherosclerosis 2009; 205:296-301. [DOI: 10.1016/j.atherosclerosis.2008.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 11/24/2008] [Accepted: 12/01/2008] [Indexed: 10/21/2022]
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Collins N, Tighe AP, Brunton SA, Kris-Etherton PM. Differences between Dietary Supplement and Prescription Drug Omega-3 Fatty Acid Formulations: A Legislative and Regulatory Perspective. J Am Coll Nutr 2008; 27:659-66. [DOI: 10.1080/07315724.2008.10719743] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Sadovsky R, Collins N, Tighe AP, Safeer RS, Morris CM, Brunton SA. Dispelling the myths about omega-3 fatty acids. Postgrad Med 2008; 120:92-100. [PMID: 18654074 DOI: 10.3810/pgm.2008.07.1796] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Although there is an enormous amount of information available on omega-3 fatty acids, it is sometimes misleading, contradictory, and unsupported by scientific fact. Consumers and medical professionals may be confused regarding the potential value of omega-3 fatty acid supplements, despite having either read or heard about fi sh oil consumption and/or omega-3 fatty acid benefits and risks. The availability of a prescription formulation of omega-3-acid ethyl esters (P-OM3) has provided important new information that helps to dispel the myths and alleviate concerns surrounding the use of omega-3 fatty acids in clinical practice. The safety and efficacy of P-OM3, but not dietary-supplement omega-3 fatty acids, are documented in placebo-controlled trials. In general, studies using Food and Drug Administration-approved dosages of P-OM3 have not substantiated various myths surrounding the negative effects of omega-3 fatty acids. Thus, there are now evidence-based clinical guidelines for the use of omega-3 fatty acids in clinical practice.
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Affiliation(s)
- Richard Sadovsky
- SUNY Health Science Center, Brooklyn College of Medicine, Brooklyn, NY 11203, USA.
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Eslick GD, Howe PRC, Smith C, Priest R, Bensoussan A. Benefits of fish oil supplementation in hyperlipidemia: a systematic review and meta-analysis. Int J Cardiol 2008; 136:4-16. [PMID: 18774613 DOI: 10.1016/j.ijcard.2008.03.092] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Revised: 03/24/2008] [Accepted: 03/29/2008] [Indexed: 10/21/2022]
Abstract
BACKGROUND Fish oils have been widely reported as a useful supplement to reduce fasting blood triglyceride levels in individuals with hyperlipidemia. We performed an updated meta-analysis to quantitatively evaluate all the randomized trials of fish oils in hyperlipidemic subjects. METHODS We conducted a systematic literature search using several electronic databases supplemented by manual searches of published reference lists, review articles and conference abstracts. We included all placebo-controlled randomized trials of parallel design that evaluated any of the main blood lipid outcomes: total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol or triglycerides (TG). Data were pooled using DerSimonian-Laird's random effects model. RESULTS The final analysis comprised of 47 studies in otherwise untreated subjects showed that taking fish oils (weighted average daily intake of 3.25 g of EPA and/or DHA) produced a clinically significant reduction of TG (-0.34 mmol/L, 95% CI: -0.41 to -0.27), no change in total cholesterol (-0.01 mmol/L, 95% CI: -0.03 to 0.01) and very slight increases in HDL (0.01 mmol/L, 95% CI: 0.00 to 0.02) and LDL cholesterol (0.06 mmol/L, 95% CI: 0.03 to 0.09). The reduction of TG correlated with both EPA+DHA intake and initial TG level. CONCLUSION Fish oil supplementation produces a clinically significant dose-dependent reduction of fasting blood TG but not total, HDL or LDL cholesterol in hyperlipidemic subjects.
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Affiliation(s)
- Guy D Eslick
- Centre for Complementary Medicine Research, University of Western Sydney, Sydney, New South Wales, Australia.
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Brunton S, Collins N. Differentiating prescription omega-3-acid ethyl esters (P-OM3) from dietary-supplement omega-3 fatty acids. Curr Med Res Opin 2007; 23:1139-45. [PMID: 17519081 DOI: 10.1185/030079907x188017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND A reliable means of treating hyper-triglyceridemia is the use of large doses of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Modest levels of EPA and DHA may be obtained from food, particularly fatty fish. OBJECTIVES This article is intended to review clinically relevant differences between dietary-supplement omega-3 fatty acids and prescription omega-3-acid ethyl esters (P-OM3). METHODS PubMed and the Food and Drug Administration (FDA) Website were searched for articles published between 1995 and 2007 that contained the terms fish oil, fatty acids, n-3 fatty acids, omega fatty acids, docosahexaenoic acid, or eicosapentaenoic acid. Articles discussing sources, recommended intake, and differences among various formulations of omega-3 fatty acids were selected for review. A limitation to this review is the lack of head-to-head clinical trials using P-OM3 and dietary-supplement omega-3 fatty acids. RESULTS Many types of nonprescription dietary supplements of omega-3 fatty acids are available; however, the efficacy, quality, and safety of these products are open to question because they are not regulated by the same standards as pharmaceutical agents. P-OM3 is the only omega-3 fatty acid product (Omacor capsules) approved by the US FDA available in the United States as an adjunct to diet to reduce very high (> or = 500 mg/dL) triglyceride levels in adult patients. CONCLUSIONS P-OM3 can be used with confidence by practitioners who want to provide therapeutic doses of omega-3 fatty acids in a preparation that has been documented to be both safe and effective.
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Abstract
PURPOSE OF REVIEW Fish oils rich in n-3 fatty acids reduce serum triglyceride levels. This well known effect has been shown to be caused by decreased very low-density lipoprotein triglyceride secretion rates in kinetic studies in humans. Animal studies have explored the biochemical mechanisms underlying this effect. Triglyceride synthesis could be reduced by n-3 fatty acids in three general ways: reduced substrate (i.e. fatty acids) availability, which could be secondary to increase in beta-oxidation, decreased free fatty acids delivery to the liver, decreased hepatic fatty acids synthesis; increased phospholipid synthesis; or decreased activity of triglyceride-synthesizing enzymes (diacylgylcerol acyltranferase or phosphatidic acid phosphohydrolase). RECENT FINDINGS Rarely were experimental conditions used in rat studies physiologically relevant to the human situation in which 1.2% energy as n-3 fatty acids lowers serum triglyceride levels. Nevertheless, the most consistent effect of n-3 fatty acids feeding in rats is to decrease lipogenesis. Increased beta-oxidation was frequently, but not consistently, reported with similar numbers of studies reporting increased mitochondrial compared with peroxisomal oxidation. Inhibition of triglyceride-synthesizing enzymes was only occasionally noted. SUMMARY As the vast majority of studies fed unphysiologically high doses of n-3 fatty acids, these findings in rats must be considered tentative, and the mechanism by which n-3 fatty acids reduce triglyceride levels in humans remains speculative.
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Mooradian AD, Haas MJ, Wong NCW. The effect of select nutrients on serum high-density lipoprotein cholesterol and apolipoprotein A-I levels. Endocr Rev 2006; 27:2-16. [PMID: 16243964 DOI: 10.1210/er.2005-0013] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
One of the factors contributing to the increased risk of developing premature atherosclerosis is low plasma concentrations of high-density lipoprotein (HDL) cholesterol (HDLc). Multiple potential mechanisms account for the cardioprotective effects of HDL and its main protein apolipoprotein A-I (apo A-I). The low plasma concentrations of HDL could be the result of increased fractional clearance and reduced expression of apo A-I. To this end, nutrients play an important role in modulating the fractional clearance rate, as well as the rate of apo A-I gene expression. Because medical nutrition therapy constitutes the cornerstone of management of dyslipidemias, it is essential to understand the mechanisms underlying the changes in HDL level in response to alterations in dietary intake. In this review, we will discuss the effect of select nutrients on serum HDLc and apo A-I levels. Specifically, we will review the literature on the effect of carbohydrates, fatty acids, and ketones, as well as some of the nutrient-related metabolites, such as glucosamine and the prostanoids, on apo A-I gene expression. Because there are multiple mechanisms involved in the regulation of serum HDLc levels, changes in gene transcription do not necessarily correlate with clinical observations on serum levels of HDLc.
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Affiliation(s)
- Arshag D Mooradian
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, St. Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, Missouri 63104, USA.
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Hashimoto M, Hossain S, Tanabe Y, Shido O. Effects of aging on the relation of adenyl purine release with plasma membrane fluidity of arterial endothelial cells. Prostaglandins Leukot Essent Fatty Acids 2005; 73:475-83. [PMID: 16165346 DOI: 10.1016/j.plefa.2005.07.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2005] [Accepted: 07/31/2005] [Indexed: 11/15/2022]
Abstract
Age-related changes in adenyl purine release from rat arteries and endothelial cell (EC) plasma membrane (PM) fluidity were studied. High performance liquid chromatography-fluorescence revealed that aging significantly decreased the release of adenyl purines. Pyrene-excimer spectroscopy disclosed that EC PM fluidity of aged rats decreased more significantly than that of young rats. An increase in cholesterol content and a decrease in the unsaturation index (USI) of fatty acids in cholesterol-enriched ECs reduced PM fluidity and 5'-nucleotidase (5'-ND) activity (measured by coupled assay of adenosine deaminase and glutamate dehydrogenase). Moreover, a decrease in cholesterol content and an increase in the USI of fatty acyl chains of the PM in docosahexaenoic acid-enriched ECs concurrently increased enzyme activity and extracellular adenosine. Therefore, decreases in PM fluidity, observed with age-dependent increased cholesterol and decreased USI, induce a decrease in 5'-ND activity, decrease extracellular adenosine levels, and might relate to hypertension in aged rats.
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Affiliation(s)
- Michio Hashimoto
- Department of Environmental Physiology, Shimane University, Faculty of Medicine, Izumo, Japan.
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Lu G, Windsor SL, Harris WS. Omega-3 fatty acids alter lipoprotein subfraction distributions and the in vitro conversion of very low density lipoproteins to low density lipoproteins. J Nutr Biochem 2005; 10:151-8. [PMID: 15539283 DOI: 10.1016/s0955-2863(98)00094-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/1998] [Accepted: 11/11/1998] [Indexed: 10/16/2022]
Abstract
The purpose of this study was to determine the effects of a fish oil concentrate (FOC) on the in vitro conversion of very low density lipoproteins (VLDL) to intermediate (IDL) and low density lipoproteins (LDL). Six hypertriglyceridemic patients were randomly allocated to receive either placebo (olive oil) or FOC (1 g/14 kg body weight/day) for 4 weeks in a crossover study with a 4-week washout period. The FOC provided 3 g of eicosapentaenoic + docosahexaenoic acid per 70 kg of body weight, and it lowered plasma triglyceride and VLDL cholesterol levels by 35% and 42%, respectively. Decreases in the largest particles (VLDL(1)) were primarily responsible, with no effect noted in smaller VLDL particles (VLDL(2) and VLDL(3)). The FOC increased LDL cholesterol levels by 25% (P < 0.06) but did not affect LDL particle size. VLDL(1) and VLDL(3) were incubated in vitro with human postheparin lipases. Although triglycerides from both types of VLDL were hydrolyzed to the same extent with both treatments, particles isolated during the FOC phase were more readily converted into IDL and LDL than were control particles. These data suggest that the marine omega3 fatty acids may enhance the propensity of VLDL to be converted to LDL, partly explaining the decreased VLDL and increased LDL levels in FOC-treated patients.
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Affiliation(s)
- G Lu
- Lipoprotein Research Laboratory, Mid America Heart Institute of Saint Luke's Hospital, University of Missouri-Kansas City, Department of Medicine, Kansas City, MO, USA
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31
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Lin MH, Lu SC, Huang PC, Liu YC, Liu SY. The amount of dietary cholesterol changes the mode of effects of (n-3) polyunsaturated fatty acid on lipoprotein cholesterol in hamsters. ANNALS OF NUTRITION AND METABOLISM 2004; 48:321-8. [PMID: 15467282 DOI: 10.1159/000081199] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2003] [Accepted: 01/19/2004] [Indexed: 11/19/2022]
Abstract
This study was designed to investigate the effects of the interaction between dietary (n-3) polyunsaturated fatty acids (PUFA) and different dietary cholesterol content on plasma and liver cholesterol in hamsters. Male Syrian hamsters consumed diets containing an incremental increase in dietary cholesterol content (0, 0.025, 0.05, 0.1 and 0.2%, w/w) with either (n-3) PUFA (21 g/100 g fatty acids) or (n-6) PUFA (37.4 g/100 g fatty acids) fat for 6 weeks. In hamsters fed the nonatherogenic diet (0 or 0.025% dietary cholesterol), very low density lipoprotein (VLDL)-cholesterol levels in the (n-3) PUFA group were not significantly different from those in the (n-6) PUFA group, and low density lipoprotein (LDL)-cholesterol levels in the (n-3) PUFA group were significantly lower than those in the (n-6) PUFA group. In contrast, in hamsters fed the atherogenic diet (0.1 or 0.2% dietary cholesterol), VLDL- and LDL-cholesterol levels in the (n-3) PUFA group were significantly higher than those in the (n-6) PUFA group, in a dose-dependent manner. When the hamsters were fed with 0, 0.025, 0.05, 0.1 or 0.2% (w/w) dietary cholesterol, high density lipoprotein (HDL) cholesterol concentration was significantly lower in the (n-3) PUFA group than those in the (n-6) PUFA group. Hepatic cholesteryl esters were significantly lower, while hepatic microsomal acyl-coenzyme A:cholesterol acyltransferase activity and VLDL-cholesteryl esters were significantly higher in hamsters fed (n-3) PUFA with the atherogenic diet (0.1 or 0.2% dietary cholesterol) than in those fed (n-6) PUFA with the atherogenic diet. Our results demonstrate that the amount of dietary cholesterol is an important factor in determining the mode and extent of effects of dietary (n-3) PUFA, especially on VLDL- and LDL-cholesterol levels. When dietary cholesterol intake was above 0.1% (w/w), the plasma cholesterol-lowering effect of (n-3) PUFA disappeared, and instead, it showed a cholesterol-increasing effect. However, the effects of dietary (n-3) PUFA on HDL-cholesterol are independent of dietary cholesterol content.
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Affiliation(s)
- Mei-Huei Lin
- Department of Biotechnology, Chia Nan University of Pharmacy and Science, Tainan, Taiwan/ROC.
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Abstract
Impaired clearance of chylomicron remnants is associated with increased risk of atherosclerosis and cardiovascular disease. An intake of 40 to 50 g of fat in a meal results in significant lipemia in healthy adults, with consecutive fat-containing meals enhancing the lipemia. This would suggest that limiting fat intake to approximately 30 g on each eating occasion would minimize postprandial lipemia. Sedentary behavior and obesity independently impair the postprandial metabolism of lipids. Postprandial lipemia causes endothelial dysfunction and results in a transient increase in factor VII activated (FVIIa) concentration. Plasminogen activator inhibitor type-1 activity is associated with fasting plasma triacylglycerol concentration, but is not influenced by postprandial lipemia. Trans-18:1 acid appears to increase cholesterol ester transfer activity acutely compared with oleate. Randomized stearic acid-rich fats result in less postprandial lipemia and a lower postprandial increase in FVIIa, whereas unrandomized cocoa butter results in similar postprandial lipemia and increases in FVIIa compared with oleate. A background diet containing in excess of 3 g/d of long-chain omega-3 fatty acids decreases postprandial lipemia by stimulating lipoprotein lipase expression and decreasing very low-density lipoprotein synthesis, but a diet enriched in alpha-linolenic acid (up to 9.5 g/d) does not show these effects. Future research on diet and postprandial lipids needs to exploit newly gained knowledge on the regulation of adipocyte metabolism by adipokines and nuclear hormone receptors, particularly with regard to fat patterning and reverse cholesterol transport.
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Affiliation(s)
- Tom A B Sanders
- Nutrition Food and Health Research Centre, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, United Kingdom.
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Park Y, Harris WS. Omega-3 fatty acid supplementation accelerates chylomicron triglyceride clearance. J Lipid Res 2003; 44:455-63. [PMID: 12562865 DOI: 10.1194/jlr.m200282-jlr200] [Citation(s) in RCA: 239] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Omega-3 fatty acids (FAs) reduce postprandial triacylglycerol (TG) concentrations. This study was undertaken to determine whether this effect was due to reduced production or increased clearance of chylomicrons. Healthy subjects (n = 33) began with a 4-week, olive oil placebo (4 g/d) run-in period. After a 4-week wash-out period, subjects were randomized to supplementation with 4 g/d of ethyl esters of either safflower oil (SAF), eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA) for 4 weeks. Results for EPA and DHA were similar, and therefore the data were combined into one omega-3 FA group. Omega-3 FA supplementation reduced the postprandial TG and apolipoprotein B (apo B)-48 and apoB-100 concentrations by 16% (P = 0.08), 28% (P < 0.001), and 24% (P < 0.01), respectively. Chylomicron TG half-lives in the fed state were reduced after omega-3 FA treatment (6.0 +/- 0.5 vs. 5.1 +/- 0.4 min; P < 0.05), but not after SAF (6.9 +/- 0.7 vs. 7.1 +/- 0.7 min). Omega-3 FA supplementation decreased chylomicron particle sizes (mean diameter; 293 +/- 44 vs. 175 +/- 25 nm; P < 0.01) and increased preheparin lipoprotein lipase (LPL; 0.6 +/- 0.1 vs. 0.9 +/- 0.1 micromol/h/ml; P < 0.05) activity during the fed state, but had no effect on postheparin LPL or hepatic lipase activities. The results suggest that omega-3 FA supplementation accelerates chylomicron TG clearance by increasing LPL activity, and that EPA and DHA are equally effective.
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Affiliation(s)
- Yongsoon Park
- Department of Medicine, University of Missouri, Kansas City, MO 64108, USA
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Effect of a Supplemented Diet with Canned Sardine on the Lipid Fraction of Human Plasma and Erythrocytes. JOURNAL OF AQUATIC FOOD PRODUCT TECHNOLOGY 2002. [DOI: 10.1300/j030v11n03_14] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Dietary n-3 polyunsaturated fat increases the fractional catabolic rate of medium-sized HDL particles in African green monkeys. J Lipid Res 2001. [DOI: 10.1016/s0022-2275(20)30279-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Arrol S, Mackness MI, Durrington PN. The effects of fatty acids on apolipoprotein B secretion by human hepatoma cells (HEP G2). Atherosclerosis 2000; 150:255-64. [PMID: 10856517 DOI: 10.1016/s0021-9150(99)00374-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have investigated the effect of fatty acids on the rate of apolipoprotein B (apo B) secretion by human hepatoma cells (Hep G2). When Hep G2 cells were maintained in tissue culture flasks oleic acid up to 0.4 mM increased apo B secretion in a dose-dependent manner, whereas increases in triacylglycerol (TG) were smaller and dose dependency was less evident. In the absence of oleic acid, apo B accumulating in the tissue culture medium was predominantly in lipoproteins of higher density than very low density lipoproteins (VLDL). However, when the rate of secretion was stimulated with oleic acid the apo B-containing lipoproteins became lower in density. We postulated that there was a high rate of lipolysis of newly secreted VLDL by Hep G2 cells, which would account both for the relatively smaller effect of oleic acid on TG as opposed to apo B accumulating in the culture medium and the predominance of apo B in lipoproteins of a higher density than VLDL, which became less evident when VLDL secretory rates were stimulated by oleic acid. To test this hypothesis, cultured Hep G2 cells were transferred to columns containing Cytodex beads, permitting their continuous perfusion with culture medium so that newly secreted VLDL did not remain in contact with the cells. Apo B recovered from the perfusate was largely in VLDL range lipoproteins and the TG measured in the perfusate indicated that the true secretory rate of TG-rich lipoproteins was substantially higher than had been reflected by TG accumulating in culture medium left in contact with cells. Apo B measured in the culture medium of Hep G2 cells may thus be a better reflection of VLDL secretion, even though it is contained in higher density lipoproteins due to removal of TG by lipolysis. The effects of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) on apo B (apo B) secretion by Hep G2 cells maintained in tissue culture flasks were next investigated. SFA (0.4 mM), with the exception of stearic acid (C18:0), increased apo B secretion. Lauric acid (C12:0) increased apo B secretion by 32%, myristic acid (C14:0) by 41% (P<0.005), palmitic acid (C16:0) by 154% (P<0.025), and arachidic acid (C20:0) by 186% (P<0.005). The effect of MUFA (0.4 mM) was to increase apo B secretion, oleic acid (C18:1) by 239% ((P<0.0005) and palmitoleic acid (C16: 1) by 125% (P<0.005). Of the PUFA investigated, linolenic acid (C18:3) (0.4 mM) did not have any significant effect on apo B secretion, whereas linoleic acid (C18:2) (0.4mM) arachidonic acid (C20:4) (0.1 mM) and eicosapentaenoic acid (C20:5) (0.1 mM) caused significant increases of 164, 171 and 171%, respectively (P<0.005). The fatty acids studied increased intracellular TG and cholesteryl ester concentrations to varying extents. The increase in intracellular TG produced by the different fatty acids correlated with the rate of apo B secretion (r=0.6; P<0.05). In this human hepatoma cell line, with the exception of the saturated fatty acids, the rate of secretion of apo B-containing lipoproteins does not follow the same pattern as changes in circulating low density lipoprotein (LDL) concentrations reported with dietary manipulation in man. If our findings reflect the in vivo situation, we suggest that whilst the dietary effects of SFA on serum LDL may in part be determined by the hepatic apo B secretory rate, the effects of MUFA and PUFA must be largely mediated through a catabolic effect rather than an effect on hepatic secretion. The marked increase in apo B secretion with the more highly polyunsaturated fatty acids, such as eicosapentaenoic acid, may also explain why they do not lower circulating LDL, despite reports of their apparently favourable effect on LDL-receptor mediated clearance.
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Affiliation(s)
- S Arrol
- The University Department of Medicine, Manchester Royal Infirmary, Oxford Road, M13 9WL, Manchester, UK
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37
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Affiliation(s)
- P Fürst
- Institute for Biological Chemistry and Nutrition, University of Hohenheim, Stuttgart, Germany
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38
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Hsu HC, Lee YT, Chen MF. Effect of n-3 fatty acids on the composition and binding properties of lipoproteins in hypertriglyceridemic patients. Am J Clin Nutr 2000; 71:28-35. [PMID: 10617943 DOI: 10.1093/ajcn/71.1.28] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Treatment of hyperlipidemic patients with fish oil results in an increase in plasma LDL cholesterol despite a marked decrease in the LDL precursor, VLDL. OBJECTIVE We studied the relation between VLDL composition and LDL concentrations. DESIGN Fourteen hypertriglyceridemic patients were treated with encapsulated fish oil (containing 1.45 g eicosapentaenoic acid and 1. 55 g docosahexaenoic acid/d) for 4 wk. Venous blood samples were collected before and after treatment. Eleven normolipidemic subjects served as a control group. RESULTS Fish oil effectively lowered plasma lipid and apolipoprotein (apo) E concentrations in the hypertriglyceridemic patients, whereas apo B concentrations increased. The lipid and apolipoprotein content of VLDL decreased, whereas LDL cholesterol and LDL apo B increased. Fractionation of VLDL by heparin-affinity chromatography showed that before treatment hypertriglyceridemic patients had more VLDL in the 0.05-mol NaCl/L subfraction and less in the 0.20-mol/L subfraction than did control subjects (P < 0.05), whereas the subfraction distribution pattern was normalized after fish-oil treatment. Nevertheless, plasma concentrations of the 0.05-mol NaCl/L subfraction were decreased and those of the 0.20-mol/L subfraction were increased in hypertriglyceridemic patients after fish-oil treatment (P < 0.05). Fish-oil treatment both enhanced VLDL binding and lowered LDL binding to fibroblasts. CONCLUSION Treatment of hypertriglyceridemic patients with fish oil caused differential effects on VLDL subfractions and decreased LDL binding to fibroblast receptors, which may have contributed to the paradoxical increase in LDL-cholesterol concentrations.
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Affiliation(s)
- H C Hsu
- Department of Internal Medicine (Cardiology), National Taiwan University Hospital, Taipei, Taiwan
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39
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Félix Rodríguez Vidigal F, Muñoz Sanz A. Alteraciones del metabolismo de los lípidos en los pacientes infectados por el virus de la inmunodeficiencia humana. Una hipótesis acerca de su patogenia. Med Clin (Barc) 2000. [DOI: 10.1016/s0025-7753(00)71490-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Leng GC, Taylor GS, Lee AJ, Fowkes FG, Horrobin D. Essential fatty acids and cardiovascular disease: the Edinburgh Artery Study. Vasc Med 1999; 4:219-26. [PMID: 10613625 DOI: 10.1177/1358836x9900400403] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this study was to determine whether plasma and red cell fatty acid levels were associated with cardiovascular disease, and whether any association was independent of other major risk factors. Over 1100 subjects were examined in a random sample survey of the general population (the Edinburgh Artery Study). Fatty acids were measured in three plasma fractions (triglyceride, cholesteryl ester and phospholipid) and in red cell phospholipids. Fatty acid levels in groups with cardiovascular disease (myocardial infarction (MI), angina and lower limb disease) were compared with a no disease group. In the cholesteryl ester and phospholipid fractions there were significantly lower levels of eicosapentaenoic acid in the MI group on univariate analysis (p<0.05), but not when adjusted for age, sex, smoking and systolic blood pressure using logistic regression. In the red cell fraction, alpha-linolenic acid was significantly lower in those with stroke (p<0.01) and lower limb disease (p<0.05). Linoleic acid was significantly raised in the triglyceride fraction in those with MI, probably reflecting recent dietary changes. There were significant increases in dihomo-gamma-linolenic acid in the phospholipid and red cell fractions in those with MI, and in the phospholipid fraction in the stroke group. These results do not support the hypothesis that n-6 fatty acids are protective against cardiovascular disease, although there may be some beneficial effects of the n-3 fatty acid, alpha-linolenic acid. Results from cross-sectional surveys must, however, be interpreted with caution because the presence of disease may affect dietary intake.
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Affiliation(s)
- G C Leng
- Department of Public Health Sciences, Edinburgh University, Scotland, UK
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Abstract
Human beings evolved consuming a diet that contained about equal amounts of n-3 and n-6 essential fatty acids. Over the past 100-150 y there has been an enormous increase in the consumption of n-6 fatty acids due to the increased intake of vegetable oils from corn, sunflower seeds, safflower seeds, cottonseed, and soybeans. Today, in Western diets, the ratio of n-6 to n-3 fatty acids ranges from approximately 20-30:1 instead of the traditional range of 1-2:1. Studies indicate that a high intake of n-6 fatty acids shifts the physiologic state to one that is prothrombotic and proaggregatory, characterized by increases in blood viscosity, vasospasm, and vasoconstriction and decreases in bleeding time. n-3 Fatty acids, however, have antiinflammatory, antithrombotic, antiarrhythmic, hypolipidemic, and vasodilatory properties. These beneficial effects of n-3 fatty acids have been shown in the secondary prevention of coronary heart disease, hypertension, type 2 diabetes, and, in some patients with renal disease, rheumatoid arthritis, ulcerative colitis, Crohn disease, and chronic obstructive pulmonary disease. Most of the studies were carried out with fish oils [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)]. However, alpha-linolenic acid, found in green leafy vegetables, flaxseed, rapeseed, and walnuts, desaturates and elongates in the human body to EPA and DHA and by itself may have beneficial effects in health and in the control of chronic diseases.
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Affiliation(s)
- A P Simopoulos
- Center for Genetics, Nutrition and Health, Washington, DC 20009
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42
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Hashimoto M, Shinozuka K, Gamoh S, Tanabe Y, Hossain MS, Kwon YM, Hata N, Misawa Y, Kunitomo M, Masumura S. The hypotensive effect of docosahexaenoic acid is associated with the enhanced release of ATP from the caudal artery of aged rats. J Nutr 1999; 129:70-6. [PMID: 9915878 DOI: 10.1093/jn/129.1.70] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Fish oils have been shown to lower blood pressure in hypertensive subjects. To determine the mechanism of this hypotensive effect, we examined the effects of docosahexaenoic acid (DHA), one of the (n-3) polyunsaturated fatty acids in fish oil, on blood pressure and on the release of adenyl purines, such as ATP, ADP, AMP and adenosine, from the caudal arteries of aged rats. Aged female Wistar rats (100 wk) were fed a high cholesterol diet and were administered intragastrically ethyl all-cis-4,7,10,13,16,19-docosahexaenoate [300 mg/(kg.d)] for 12 wk (DHA group) or vehicle alone (control group). Compared with the controls, rats supplemented with DHA had significantly greater (10.1%) DHA concentrations in the caudal arteries. This was associated with more total (n-3) arterial fatty acids, a greater unsaturation index of arterial fatty acids, 43.9% lower plasma noradrenaline levels and the repression of the elevation in blood pressure observed with advancing age. The amount of purines released, both spontaneously and in response to noradrenaline, from arterial segments of DHA-supplemented rats was significantly higher than that released from tissues of control rats. Regression analysis revealed significant negative relationships between the total amount of purines released from the artery and the systolic (SBP) and diastolic (DBP) blood pressures. These results suggest that in aged rats, supplementation with DHA alters the membrane fatty acid composition as well as the amount of ATP released from vascular endothelial cells and decreases plasma noradrenaline, and that these factors may ameliorate the rise in blood pressure normally associated with advancing age.
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Affiliation(s)
- M Hashimoto
- Department of Physiology, Shimane Medical University, Izumo 693-8501, Japan
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Effects of dietary fish oil on serum lipids and VLDL kinetics in hyperlipidemic apolipoprotein E*3-Leiden transgenic mice. J Lipid Res 1998. [DOI: 10.1016/s0022-2275(20)32542-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Prasad K, Mantha SV, Muir AD, Westcott ND. Reduction of hypercholesterolemic atherosclerosis by CDC-flaxseed with very low alpha-linolenic acid. Atherosclerosis 1998; 136:367-75. [PMID: 9543108 DOI: 10.1016/s0021-9150(97)00239-6] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Flaxseed (Type I flaxseed) with 51-55% alpha-linolenic acid in its oil and richest source of plant lignans, has been shown to reduce hypercholesterolemic atherosclerosis by 46% without lowering serum lipids. Antiatherogenic activity was claimed to be due to its alpha-linolenic acid and/or lignan content. If alpha-linolenic acid component of flaxseed is responsible for antiatherogenic activity, then, CDC-flaxseed (Type II flaxseed) which has similar oil and lignan content but has very little (2-3% of the total oil) alpha-linolenic acid would have no antiatherogenic effect. An investigation, therefore, was made of Type II flaxseed on high cholesterol diet-induced atherosclerosis and serum lipids [total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C)] in rabbits. Rabbits were assigned to four groups: Group I, Control; Group II, Type II flaxseed diet (7.5 g/kg orally daily); Group III, 1% cholesterol diet; Group IV, 1% cholesterol diet supplemented with Type II flaxseed (7.5 g/kg orally daily). Blood samples were collected before (0 time) and after 4 and 8 weeks of experimental diets for measurement of serum lipids. Aorta was removed at the end of 8 weeks for assessment of atherosclerotic plaques. Serum TC, LDL-C, TC/HDL-C, and LDL-C/HDL-C were lower in Group IV as compared to Group III by 14 and 31%, 17 and 32%, 28 and 34% and 24 and 32%, respectively, at 4 and 8 weeks. HDL-C was not affected by Type II flaxseed in hypercholesterolemic rabbit. TG and VLDL-C were markedly increased in Group IV as compared to Group III. Type II flaxseed reduced the development of atherosclerosis by 69%. Histological changes in the atherosclerotic regions were qualitatively similar in Groups III and IV. Results indicate that reduction in hypercholesterolemic atherosclerosis by Type II flaxseed is due to a decrease in serum TC and LDL-C. In conclusion, antiatherogenic activity of Type II flaxseed is not due to alpha-linolenic acid.
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Affiliation(s)
- K Prasad
- Department of Physiology, College of Medicine, University of Saskatchewan and Agriculture and Agrifood Canada, Saskatoon
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Fisher WR, Zech LA, Stacpoole PW. Apolipoprotein B metabolism in hypertriglyceridemic diabetic patients administered either a fish oil- or vegetable oil-enriched diet. J Lipid Res 1998. [DOI: 10.1016/s0022-2275(20)33900-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Sanders TA, Oakley FR, Miller GJ, Mitropoulos KA, Crook D, Oliver MF. Influence of n-6 versus n-3 polyunsaturated fatty acids in diets low in saturated fatty acids on plasma lipoproteins and hemostatic factors. Arterioscler Thromb Vasc Biol 1997; 17:3449-60. [PMID: 9437192 DOI: 10.1161/01.atv.17.12.3449] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Modification of dietary fat composition may influence hemostatic variables, which are associated with increased risk of coronary heart disease (CHD). To address this question, we performed a controlled feeding study on 26 healthy male nonsmoking subjects with diets of differing fat composition. For the first 3 weeks, the subjects were given a diet calculated to supply 30% energy as total fat: 8% as monounsaturated, 4% as polyunsaturated, and 16% energy as saturated fatty acids, respectively (saturated diet). This was followed immediately by two diets taken in random order, each of 3-week duration and separated by an 8-week washout period on the subject's usual diet. Both diets were calculated to supply 30% of energy as fat: 14% monounsaturated, 6% as polyunsaturated, and 8% energy as saturated fatty acids. They both provided 5 g (approximately 1.7% energy) more of polyunsaturated fatty acids than the saturated fat diet; in one diet as long-chain n-3 fatty acids (n-3 diet) and in the other as linoleic acid (n-6 diet). Fasting plasma lipids, lipoproteins, and hemostatic factors were measured on the final 3 days of each dietary period. In a subset of 9 subjects the postprandial responses to a test meal were studied on the penultimate day of each period, each meal having the fat composition of its parent diet. On the n-3 diet compared with the n-6 diet, plasma triglyceride, HDL3 cholesterol, apoprotein AII, and fibrinogen concentrations were lower and HDL2 cholesterol concentration was higher (P = .0001, P = .003, P = .0001, P = .004, and P = .001, respectively). On both the n-3 and n-6 diets compared with the saturated diet, fasting plasma total and LDL cholesterol, apoprotein B, beta-thromboglobulin concentrations, and platelet counts were lower (P < .0001, P < .0001, P < .001, P < .01, and P < .05 respectively) and plasma Lp(a) and von Willebrand factor concentrations were higher (P = .02 and P < .01, respectively). Fasting factor VII coagulant activity (VIIc) was increased and apoprotein AI concentration reduced following the n-3 diet (P = .004 and P = .01, respectively) compared with the saturated diet. Plasma fibrinogen concentration was significantly greater following the n-6 diet than on the saturated diet (P = .02). Postprandially, plasma triglyceridemia was greater on the n-6 diet and lowest on the n-3 diet (P < .001) with the saturated diet being intermediate. Plasma VIIc was increased at 4 hours following the standardized test meals on the n-3 and n-6 diets (both P < .05) but not on the saturated diet. An increased intake of long chain n-3 fatty acids decreases fasting plasma triglyceride and apoprotein AII concentrations and increases HDL2 cholesterol concentrations and results in less postprandial lipemia but leads to an increase in VIIc. An increased intake of linoleic acid may raise plasma fibrinogen concentration. Decreasing the intake of saturated fatty acids reduces plasma LDL cholesterol and apoprotein B without affecting HDL cholesterol concentration independent of the type of polyunsaturated fatty acids in the diet. When advice is given to reduce saturated fat intake, it is important to ensure an appropriate ratio of n-3/n-6 fatty acids in the diet.
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Affiliation(s)
- T A Sanders
- Nutrition, Food & Health Research Centre, Kings College London
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Willumsen N, Vaagenes H, Rustan AC, Grav H, Lundquist M, Skattebøl L, Songstad J, Berge RK. Enhanced hepatic fatty acid oxidation and upregulated carnitine palmitoyltransferase II gene expression by methyl 3-thiaoctadeca-6,9,12,15-tetraenoate in rats. JOURNAL OF LIPID MEDIATORS AND CELL SIGNALLING 1997; 17:115-34. [PMID: 9459137 DOI: 10.1016/s0929-7855(97)00024-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This study reports the effects of a novel polyunsaturated 3-thia fatty acid, methyl 3-thiaoctadeca-6,9,12,15-tetraenoate on serum lipids and key enzymes in hepatic fatty acid metabolism compared to a saturated 3-thia fatty acid, tetradecylthioacetic acid. Palmitic acid treated rats served as controls. Fatty acids were administered by gavage in daily doses of 150 mg/kg body weight for 10 days. The aim of the present study was: (a) To investigate the effect of a polyunsaturated 3-thia fatty acid ester, methyl 3-thiaoctadeca-6,9,12,15-tetraenoate on plasma lipids in normolipidemic rats: (b) to verify whether the lipid-lowering effect could be consistent with enhanced fatty acid oxidation: and (c) to study whether decreased activity of esterifying enzymes and diversion to phospholipid synthesis is a concerted mechanism in limiting the availability of free fatty acid as a substrate for hepatic triglyceride formation. Repeated administration of the polyunsaturated 3-thia fatty acid ester for 10 days resulted in a reduction of plasma triglycerides (40%), cholesterol (33%) and phospholipids (20%) compared to controls. Administration of polyunsaturated and saturated 3-thia fatty acids (daily doses of 150 mg/kg body weight) reduced levels of lipids to a similar extent and followed about the same time-course. Both mitochondrial and peroxisomal fatty acid oxidation increased (1.4-fold- and 4.2-fold, respectively) and significantly increased activities of carnitine palmitoyltransferase (CPT) (1.6-fold), 2,4-dienoyl-CoA reductase (1.2-fold) and fatty acyl-CoA oxidase (3.0-fold) were observed in polyunsaturated 3-thia fatty acid treated animals. This was accompanied by increased CPT-II mRNA (1.7-fold). 2,4-dienoyl-CoA reductase mRNA (2.9-fold) and fatty acyl-CoA oxidase mRNA (1.7-fold). Compared to controls, the hepatic triglyceride biosynthesis was retarded as indicated by a decrease in liver triglyceride content (40%). The activities of glycerophosphate acyltransferase, acyl-CoA: 1,2-diacylglycerol acyltransferase and CTP:phosphocholine cytidylyltransferase were increased. The cholesterol lowering effect was accompanied by a reduction in HMG-CoA reductase activity (80%) and acyl-CoA:cholesterol acyltransferase activity (33%). In hepatocytes treated with methyl 3-thiaoctadeca-6,9,12,15-tetraenoate, fatty acid oxidation was increased 1.8-fold compared to controls. The results suggest that treatment with methyl 3-thiaoctadeca-6,9,12,15-tetraenoate reduces plasma triglycerides by a decrease in the availability of fatty acid substrate for triglyceride biosynthesis via enhanced fatty acid oxidation, most likely attributed to the mitochondrial fatty acid oxidation. It is hypothesized that decreased phosphatidate phosphohydrolase activity may be an additive mechanism which contribute whereby 3-thia fatty acids reduce triglyceride formation in the liver. The cholesterol-lowering effect of the polyunsaturated 3-thia fatty acid ester may be due to changes in cholesterol/cholesterol ester synthesis as 60% of this acid was observed in the hepatic cholesterol ester fraction.
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Affiliation(s)
- N Willumsen
- Department of Clinical Biology, University of Bergen, Haukeland Hospital, Norway
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Frøyland L, Vaagenes H, Asiedu DK, Garras A, Lie O, Berge RK. Hypotriacylglycerolemic component of fish oil. Prostaglandins Leukot Essent Fatty Acids 1997; 57:387-8. [PMID: 9430383 DOI: 10.1016/s0952-3278(97)90415-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- L Frøyland
- University of Bergen, Department of Clinical Biology, Haukeland Hospital, Norway
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Harris WS, Hustvedt BE, Hagen E, Green MH, Lu G, Drevon CA. N-3 fatty acids and chylomicron metabolism in the rat. J Lipid Res 1997. [DOI: 10.1016/s0022-2275(20)37258-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Otto C, Ritter MM, Soennichsen AC, Schwandt P, Richter WO. Effects of n-3 fatty acids and fenofibrate on lipid and hemorrheological parameters in familial dysbetalipoproteinemia and familial hypertriglyceridemia. Metabolism 1996; 45:1305-11. [PMID: 8843189 DOI: 10.1016/s0026-0495(96)90252-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
There is increasing evidence that hemorrheological abnormalities are associated with an enhanced risk of atherosclerosis. The n-3 fatty acids (n-3-FA) have been shown to have beneficial effects on atherosclerosis in patients with dyslipoproteinemias. We studied 23 patients with elevated plasma triglycerides to evaluate the influence of fish oil and fenofibrate therapy on hemorrheological parameters (15 patients with familial hypertriglyceridemia [FHTG] and eight with familial dysbetalipoproteinemia [FDL]). The patients (one woman and 22 men aged 45.7 +/- 2.0 years) were treated with increasing doses of n-3-FA (1.8 to 3.6 g/d: 0.9 to 1.8 g eicosapentaenoic acid and 0.6 to 1.2 g docosahexaenoic acid) for 8 weeks. Lipid parameters, whole-blood viscosity at different shear rates, plasma viscosity, fibrinogen concentration, and red blood cell aggregation (RCA) were measured at baseline and at weeks 2, 4, 8 (end of n-3-FA therapy), and 12. Compliance was ensured by measuring plasma concentrations of eicosapentaenoic acid and docosahexaenoic acid. After 12 weeks, patients began treatment with fenofibrate (250 mg daily); investigations were performed again at week 20. Total triglycerides (from 6.90 +/- 1.70 to 3.61 +/- 0.78 mmol/L in FDL and 7.44 +/- 1.50 to 4.15 +/- 0.55 in FHTG), very-low-density lipoprotein (VLDL) triglycerides, and VLDL cholesterol were significantly decreased with n-3-FA therapy in both groups (P < .05). In FHTG, low-density lipoprotein (LDL) cholesterol increased significantly (from 2.75 +/- 0.28 to 3.97 +/- 0.35 mmol/L, P < .01); in FDL, total cholesterol decreased (from 9.76 +/- 1.32 to 7.34 +/- 1.07 mmol/L, P < .05). No significant changes were observed in hemorrheological parameters, except for reduced RCA with 3.6 g n-3-FA in FHTG. However, with fenofibrate therapy, in addition to comparable lipoprotein changes seen with fish oil, fibrinogen levels and plasma and blood viscosity decreased in patients with FDL. We conclude that n-3-FA and fenofibrate have comparable effects on lipid parameters in patients with FDL and FHTG. Because of additional beneficial effects on hemorrheological parameters, fenofibrate may be preferred for the treatment of FDL.
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Affiliation(s)
- C Otto
- Medical Department II, Klinikum Grosshadern, University of Munich, Germany
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