1
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Zhao M, Shi J, Li W, Guan C, Sun C, Peng Y, Zheng J. Metabolic Activation of Gemfibrozil Mediated by Cytochrome P450 Enzymes and Sulfotransferases. Chem Res Toxicol 2022; 35:1257-1266. [PMID: 35763595 DOI: 10.1021/acs.chemrestox.2c00054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Gemfibrozil (GEM), a lipid regulator, is a fibric acid derivative widely used in the treatment of hyperlipidemia. It has been reported that GEM can induce acute liver injury in the course of therapy in clinical practice, so it is necessary to elucidate the mechanisms of toxic action. The present study focused on metabolic activation of GEM, possibly participating in GEM-mediated liver injury. A benzylic alcohol metabolite (M1), along with a phenol metabolite (M2), was detected in microsomal incubations, rat primary hepatocyte culturing, and rats given GEM. A GSH conjugate (M3) was detected in cultured rat hepatocytes after exposure to GEM. Formation of M1 was found to be NADPH dependent, and generation of M3 required M1 and 3'-phosphoadenosine-5'-phosphosulfate. It is most likely that GEM was biotransformed to M1, which was further metabolized to a sulfate. The resulting sulfate was reactive to bio-thiols. Cytochrome P450 and sulfotransferases participated in the phase I and phase II reactions, respectively. M1 and M3 were chemically synthesized, and their structures were characterized by mass spectrometry and NMR. The present study has particular value for elucidating the mechanism of liver injury caused by GEM.
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Affiliation(s)
- Min Zhao
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China
| | - Junzu Shi
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China
| | - Wei Li
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China
| | - Chunjing Guan
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China
| | - Chen Sun
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China
| | - Ying Peng
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China
| | - Jiang Zheng
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, P. R. China.,State Key Laboratory of Functions and Applications of Medicinal Plants, Key Laboratory of Pharmaceutics of Guizhou Province, Guizhou Medical University, Guiyang, Guizhou 550025, P. R. China.,Key Laboratory of Environmental Pollution, Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, Guizhou 550025, P. R. China
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2
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Scott KA, Cox PB, Njardarson JT. Phenols in Pharmaceuticals: Analysis of a Recurring Motif. J Med Chem 2022; 65:7044-7072. [PMID: 35533692 DOI: 10.1021/acs.jmedchem.2c00223] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Phenols and phenolic ethers are significant scaffolds recurring both in nature and among approved small-molecule pharmaceuticals. This compendium presents the first comprehensive compilation and analysis of the structures of U.S. FDA-approved molecules containing phenol or phenolic ether fragments. This dataset comprises 371 structures, which are strongly represented by natural products. A total of 55 of the compounds described here are on the World Health Organization's list of essential medicines. Structural analysis reveals significant differences in the physicochemical properties imparted by phenols versus phenol ethers, each having benefits and drawbacks for drug developability. Despite trends over the past decade to increase the fraction of sp3 centers in drug leads, thereby "escaping flatland", phenols and phenolic ethers are represented in 62% of small-molecule drugs approved in 2020, suggesting that this aromatic moiety holds a special place in drugs and natural products.
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Affiliation(s)
- Kevin A Scott
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States.,Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona 85721, United States
| | - Philip B Cox
- Drug Discovery Science and Technology, AbbVie Inc., 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Jon T Njardarson
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
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3
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Structural Analysis of Human Serum Albumin in Complex with the Fibrate Drug Gemfibrozil. Int J Mol Sci 2022; 23:ijms23031769. [PMID: 35163693 PMCID: PMC8836495 DOI: 10.3390/ijms23031769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/28/2022] [Accepted: 01/31/2022] [Indexed: 02/01/2023] Open
Abstract
Gemfibrozil (GEM) is an orally administered lipid-regulating fibrate derivative drug sold under the brand name Lopid®, among others. Since its approval in the early 80s, GEM has been largely applied to treat hypertriglyceridemia and other disorders of lipid metabolism. Though generally well tolerated, GEM can alter the distribution and the free, active concentration of some co-administered drugs, leading to adverse effects. Most of them appear to be related to the ability of GEM to bind with high affinity human serum albumin (HSA), the major drug-carrier protein in blood plasma. Here, we report the crystal structure of HSA in complex with GEM. Two binding sites have been identified, namely Sudlow’s binding sites I (FA7) and II (FA3–FA4). A comparison of the crystal structure of HSA in complex with GEM with those of other previously described HSA–drug complexes enabled us to appreciate the analogies and differences in their respective binding modes. The elucidation of the molecular interaction between GEM and HSA might offer the basis for the development of novel GEM derivatives that can be safely and synergistically co-administered with other drugs, enabling augmented therapeutic efficacies.
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4
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Mohanalakshmi S, Bhatt S, Ashok Kumar C. Enhanced antihyperlipidemic potential of gemfibrozil under co-administration with piperine. CURRENT RESEARCH IN PHARMACOLOGY AND DRUG DISCOVERY 2021; 2:100021. [PMID: 34909656 PMCID: PMC8663971 DOI: 10.1016/j.crphar.2021.100021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 11/15/2022] Open
Abstract
Gemfibrozil is a well-known potent antihyperlipidemic drug with the capacity to lower triglyceride and cholesterol levels, which are responsible for most cardiovascular and cerebrovascular diseases. In addition, gemfibrozil has a potent activity at elevating the high density lipoprotein levels. However, this drug has a very short half-life of about 2 h and toxicity is observed in the liver as the dose increases. The drug piperine has the capacity to enhance the bioavailability of other drugs without altering their basic properties as well as improving their activity. In this study, we aimed to enhance the bioavailability of gemfibrozil as well as making it more potent and less toxic by applying piperine as a bio-enhancer. Thus, piperine was co-administered to rats with gemfibrozil and the antihyperlipidemic activity was tested when fed on a high fat diet. The results showed that co-administration of gemfibrozil with piperine decreased the elevated triglyceride and cholesterol levels to normal, and they performed significantly better than the individual drugs. Weight gain was controlled effectively by drug administration together with piperine compared with other groups. Hepatic function analyses demonstrated that the potentiation of gemfibrozil did not alter the hepatic function but instead it improved significantly by normalizing the elevated serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, and alkaline phosphatase levels. The plasma drug concentration of gemfibrozil was studied over time, where the enhanced activity of the drug reached its Cmax within 1 h of administration and the activated drug level was observed in the blood for 4 h. Gemfibrozil is a potent antihyperlipidemic drug with a short half-life. Piperine is used as a natural bio-enhancer to improve the activities of many drugs. Lipid lowering activity of gemfibrozil enhanced by administration with piperine. Piperine enhanced the liver function and plasma concentration of gemfibrozil. Peak plasma concentration of gemfibrozil improved within 1 h.
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Affiliation(s)
- S. Mohanalakshmi
- Amity Institute of Pharmacy, Amity University, Maharajpura (Opposite Airport), Gwalior, 474005, Madhya Pradesh, India
- Corresponding author.
| | - Shvetank Bhatt
- Amity Institute of Pharmacy, Amity University, Maharajpura (Opposite Airport), Gwalior, 474005, Madhya Pradesh, India
| | - C.K. Ashok Kumar
- School of Pharmacy, Guru Nanak Institutions Technical Campus, Khanapur, Ibrahimpatam, Ranga Reddy Dist, Hyderabad, Telangana State, 501506, India
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5
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Fraz S, Lee AH, Pollard S, Srinivasan K, Vermani A, Wilson JY. Parental gemfibrozil exposure impacts zebrafish F 1 offspring, but not subsequent generations. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 212:194-204. [PMID: 31132737 DOI: 10.1016/j.aquatox.2019.04.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 04/26/2019] [Accepted: 04/29/2019] [Indexed: 06/09/2023]
Abstract
Gemfibrozil (GEM) is a fibrate lipid regulator and one of the most commonly occurring fresh water pharmaceuticals. The negative effects of fibrates including GEM on fish reproduction have been frequently reported including effects of F0 GEM exposure on reproduction of the unexposed F1 offspring. We predicted that chronic, direct exposure of zebrafish with low concentrations of GEM would adversely affect parental male reproduction and unexposed offspring for multiple generations. Adult zebrafish were exposed to 10 μg/L GEM for 6 weeks and a range of reproductive indices were analyzed. The F1-F4 offspring were reared in clean water from 3 distinct lineages where only a single or both parents were exposed and compared to a control lineage where parents were unexposed. Reproductive indices were examined in unexposed F1-F4 offspring to test the hypothesis of multi- or trans- generational impacts. Exposure to GEM caused a decline in breeding success and mean embryo production in F0 parents and a reduction in whole body 11-ketotestosterone (11-KT), altered male courtship, aggression and sperm morphology. Our results indicate that paternal exposure alone is sufficient to result in reproductive effects in unexposed male offspring but that effects are mostly limited to F1. We suggest that GEM may act as a reproductive endocrine disruptor in fish and that chronic exposure reduced male reproductive fitness but not over multiple generations.
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Affiliation(s)
- Shamaila Fraz
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada.
| | - Abigail H Lee
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada.
| | - Simon Pollard
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada.
| | - Krishna Srinivasan
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada.
| | - Abhilasha Vermani
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada.
| | - Joanna Y Wilson
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, ON, Canada.
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6
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Kalam MA, Alshehri S, Alshamsan A, Alkholief M, Ali R, Shakeel F. Solubility measurement, Hansen solubility parameters and solution thermodynamics of gemfibrozil in different pharmaceutically used solvents. Drug Dev Ind Pharm 2019; 45:1258-1264. [PMID: 30995878 DOI: 10.1080/03639045.2019.1594884] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Gemfibrozil (GEM) is cholesterol-lowering agent which is being proposed as poorly water soluble drug (PWSD). Temperature based solubility values of GEM are not yet available in literature or any pharmacopoeia/monograph. Hence, the present studies were carried out to determine the solubility of PWSD GEM (as mole fraction) in various pharmaceutically used solvents such as water (H2O), methanol (MeOH), ethanol (EtOH), isopropanol (IPA), 1-butanol (1-BuOH), 2-butanol (2-BuOH), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), ethyl acetate (EA), dimethyl sulfoxide (DMSO) and Transcutol® (THP) at the temperatures ranging from T = 298.2 K-318.2 K under atmospheric pressure P = 0.1 MPa. Equilibrium/experimental solubilities of GEM were recorded by applying a saturation shake flask methodology and regressed using 'van't Hoff and Apelblat models'. Hansen solubility parameters for GEM and various pharmaceutically used solvents were estimated using HSPiP software. The solid states of GEM (both in pure and equilibrated states) were studied by 'Differential Scanning Calorimetry' which confirmed no transformation of GEM after equilibrium. Experimental solubilities of GEM in mole fraction were observed maximum in THP (1.81 × 10-1) followed by DMSO, PEG-400, EA, 1-BuOH, 2-BuOH, IPA, EtOH, PG, MeOH, EG and H2O (3.24 × 10-6) at T = 318.2 K and similar tendencies were also recorded at T = 298.2 K, T = 303.2 K, T = 308.2 K and T = 313.2 K. 'Apparent thermodynamic analysis' on experimental solubilities furnished 'endothermic and entropy-driven dissolution' of GEM in each pharmaceutically used solvent.
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Affiliation(s)
- Mohd Abul Kalam
- a Nanobiotechnology Unit, Department of Pharmaceutics , College of Pharmacy, King Saud University , Riyadh , Saudi Arabia
| | - Sultan Alshehri
- b Department of Pharmaceutics , College of Pharmacy, King Saud University , Riyadh , Saudi Arabia
| | - Aws Alshamsan
- a Nanobiotechnology Unit, Department of Pharmaceutics , College of Pharmacy, King Saud University , Riyadh , Saudi Arabia
| | - Musaed Alkholief
- a Nanobiotechnology Unit, Department of Pharmaceutics , College of Pharmacy, King Saud University , Riyadh , Saudi Arabia
| | - Raisuddin Ali
- b Department of Pharmaceutics , College of Pharmacy, King Saud University , Riyadh , Saudi Arabia.,c Central Laboratory , Research Center, College of Pharmacy, King Saud University , Riyadh , Saudi Arabia
| | - Faiyaz Shakeel
- b Department of Pharmaceutics , College of Pharmacy, King Saud University , Riyadh , Saudi Arabia
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7
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Hong F, Xu P, Zhai Y. The Opportunities and Challenges of Peroxisome Proliferator-Activated Receptors Ligands in Clinical Drug Discovery and Development. Int J Mol Sci 2018; 19:ijms19082189. [PMID: 30060458 PMCID: PMC6121873 DOI: 10.3390/ijms19082189] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/16/2018] [Accepted: 07/24/2018] [Indexed: 12/12/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) are a well-known pharmacological target for the treatment of multiple diseases, including diabetes mellitus, dyslipidemia, cardiovascular diseases and even primary biliary cholangitis, gout, cancer, Alzheimer's disease and ulcerative colitis. The three PPAR isoforms (α, β/δ and γ) have emerged as integrators of glucose and lipid metabolic signaling networks. Typically, PPARα is activated by fibrates, which are commonly used therapeutic agents in the treatment of dyslipidemia. The pharmacological activators of PPARγ include thiazolidinediones (TZDs), which are insulin sensitizers used in the treatment of type 2 diabetes mellitus (T2DM), despite some drawbacks. In this review, we summarize 84 types of PPAR synthetic ligands introduced to date for the treatment of metabolic and other diseases and provide a comprehensive analysis of the current applications and problems of these ligands in clinical drug discovery and development.
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Affiliation(s)
- Fan Hong
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China.
- Key Laboratory for Cell Proliferation and Regulation Biology of State Education Ministry, College of Life Sciences, Beijing Normal University, Beijing 100875, China.
| | - Pengfei Xu
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China.
| | - Yonggong Zhai
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing 100875, China.
- Key Laboratory for Cell Proliferation and Regulation Biology of State Education Ministry, College of Life Sciences, Beijing Normal University, Beijing 100875, China.
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8
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Hromádka R, Kejík Z, Jakubek M, Kaplánek R, Šandriková V, Urban M, Martásek P, Král V. Pigments from Filamentous Ascomycetes for Combination Therapy. Curr Med Chem 2018; 26:3812-3834. [PMID: 29600749 DOI: 10.2174/0929867325666180330091933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/21/2018] [Accepted: 03/21/2018] [Indexed: 11/22/2022]
Abstract
Filamentous ascomycetes (Neurospora and Monascus) have been studied for a long time because of their production of secondary metabolites such as microbial pigments. The ascomycetes represent an interesting group of compounds with high potential for medicinal applications. Many recent studies have shown their efficacy in the treatment of serious pathological states such as oncological diseases, neurodegenerative diseases and hyperlipidaemia. Nevertheless, the clinical usability of ascomycetes is still limited. However, this problem can be solved by the use of these compounds with combinations of other therapeutic agents. This strategy can suppress their side effects and improve their therapeutic efficacy. Moreover, their co-application can significantly enhance conventional therapies that are used. This review summarizes and discusses the general principles of this approach, introduced and supported by numerous examples. In addition, the prediction of the future potential application of this methodology is included.
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Affiliation(s)
- Róbert Hromádka
- C2P s.r.o. Jungmannova 101 503 51 Chlumec nad Cidlinou, Czech Republic
| | - Zdeněk Kejík
- Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague 2, Czech Republic
| | - Milan Jakubek
- BIOCEV, First Faculty of Medicine, Charles University, Prumyslova 595, 252 50 Vestec, Czech Republic.,Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Robert Kaplánek
- BIOCEV, First Faculty of Medicine, Charles University, Prumyslova 595, 252 50 Vestec, Czech Republic.,Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Viera Šandriková
- C2P s.r.o. Jungmannova 101 503 51 Chlumec nad Cidlinou, Czech Republic
| | - Marian Urban
- Food Research Institute Prague, Radiova 1285/7, 1285/7, Prague 10, Czech Republic
| | - Pavel Martásek
- Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague 2, Czech Republic
| | - Vladimír Král
- BIOCEV, First Faculty of Medicine, Charles University, Prumyslova 595, 252 50 Vestec, Czech Republic.,Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
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9
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Türkoğlu E, Osma E, Elveren M. Effects of Acetaminophen (Paracetamol) and Gemfibrozil on Seed Development and Antioxidant Enzyme Activities in Different Wheat Varieties. IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY TRANSACTION A-SCIENCE 2017. [DOI: 10.1007/s40995-017-0386-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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10
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Matsuoka Y, Ike A, Ogawa M, Gondo K, Shirai K, Sugihara M, Nose D, Nishikawa H, Iwata A, Kawamura A, Mori K, Zhang B, Yasunaga S, Miura SI, Saku K. Sex difference between target levels of cholesterol-related parameters and post-PCI long-term clinical outcomes: From the FU-Registry. J Cardiol 2017; 71:259-267. [PMID: 29129396 DOI: 10.1016/j.jjcc.2017.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 09/06/2017] [Accepted: 09/19/2017] [Indexed: 01/08/2023]
Abstract
BACKGROUND Since single lipid parameters are too weak to predict the risk of coronary artery disease, we examined whether the allocation of patients into four groups based on achievement of the target levels set by the Japan Atherosclerosis Guidelines at the time of percutaneous coronary intervention (PCI) would reveal different long-term (5 years) clinical outcomes in males and females. METHODS The results of a 5-year follow-up study are summarized as FU-Registry, Long-Term Clinical Outcome Results. The subjects consisted of 1158 patients who underwent elective PCI. The male and female patients were separately allocated into four groups: (1) high-density lipoprotein cholesterol (HDL-C≥40mg/dl as well as low-density lipoprotein-cholesterol (LDL-C)≥100mg/dl); (2) HDL-C≥40mg/dl as well as LDL-C<100mg/dl; (3) HDL-C<40mg/dl as well as LDL-C≥100mg/dl; (4) HDL-C<40mg/dl as well as LDL-C<100mg/dl, for a comparison of both patient as well as lesion characteristics and the endpoint of major adverse cardiac events (MACEs). RESULTS Regarding lesion characteristics, significant differences (p<0.05) were detected in the usage rate of a drug-eluting stent (DES) as well as the bend, stent reference diameter, and stent minimum lumen diameter in females by ANOVA, and in severe calcification, the bend, and usage rate of DES (p<0.001) in males. In females, significant differences (p<0.05) were observed in MACEs and target lesion revascularization-PCI. In contrast, among males, the four groups had nearly equivalent outcomes. Uni- and multivariate analyses revealed that HDL-C as well as LDL-C in females were associated with MACEs [OR 3.29 (95% CI 1.05-8.57, p=0.04)], while no association was observed in male multivariate analysis. CONCLUSION In female patients, HDL-C<40mg/dl and LDL-C≥100mg/dl were even more strongly related to MACEs, whereas the combination of LDL-C and HDL-C was not related to MACEs in male patients.
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Affiliation(s)
- Yuta Matsuoka
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Amane Ike
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan.
| | - Masahiro Ogawa
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Kouki Gondo
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Kazuyuki Shirai
- Department of Cardiology, Fukuoka University Chikushi Hospital, Fukuoka, Japan; Division of Cardiology, Hakujyuji Hospital, Fukuoka, Japan
| | - Makoto Sugihara
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Daisuke Nose
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan; Division of Cardiology, Hakujyuji Hospital, Fukuoka, Japan
| | - Hiroaki Nishikawa
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Atsushi Iwata
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Akira Kawamura
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Ken Mori
- Department of Cardiology, Fukuoka University Chikushi Hospital, Fukuoka, Japan
| | - Bo Zhang
- Department of Biochemistry, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Shin'ichiro Yasunaga
- Department of Biochemistry, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Shin-Ichiro Miura
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Keijiro Saku
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan; General Medical Research Center, Fukuoka University School of Medicine, Fukuoka, Japan.
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11
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Sayar F, Akhondi N, Fallah S, Moalemnia AA, Cheraghi A. Association of Serum Triglyceride Level and Gemfibrozil Consumption With Periodontal Status. J Periodontol 2017; 88:457-463. [DOI: 10.1902/jop.2016.160366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Ferena Sayar
- Department of Periodontics, Tehran Dental Branch, Islamic Azad University, Tehran, Iran
| | - Nasrin Akhondi
- Department of Mathematics, South Tehran Branch, Islamic Azad University
| | | | | | - Azra Cheraghi
- Department of Periodontics, Tehran Dental Branch, Islamic Azad University, Tehran, Iran
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12
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Degirolamo C, Sabbà C, Moschetta A. Intestinal nuclear receptors in HDL cholesterol metabolism. J Lipid Res 2014; 56:1262-70. [PMID: 25070952 DOI: 10.1194/jlr.r052704] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Indexed: 12/18/2022] Open
Abstract
The intestine plays a pivotal role in cholesterol homeostasis by functioning as an absorptive and secretory organ in the reverse cholesterol transport pathway. Enterocytes control cholesterol absorption, apoAI synthesis, HDL biogenesis, and nonbiliary cholesterol fecal disposal. Thus, intestine-based therapeutic interventions may hold promise in the management of diseases driven by cholesterol overload. Lipid-sensing nuclear receptors (NRs) are highly expressed in the intestinal epithelium and regulate transcriptionally the handling of cholesterol by the enterocytes. Here, we discuss the NR regulation of cholesterol fluxes across the enterocytes with special emphasis on NR exploitation as a bona fide novel HDL-raising strategy.
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Affiliation(s)
- Chiara Degirolamo
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Tumori "Giovanni Paolo II", 70124 Bari, Italy
| | - Carlo Sabbà
- Clinica Medica "Cesare Frugoni", Department of Interdisciplinary Medicine, University of Bari "Aldo Moro", 70124 Bari, Italy
| | - Antonio Moschetta
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Tumori "Giovanni Paolo II", 70124 Bari, Italy Clinica Medica "Cesare Frugoni", Department of Interdisciplinary Medicine, University of Bari "Aldo Moro", 70124 Bari, Italy
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13
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Zhang B, Kawachi E, Miura SI, Uehara Y, Matsunaga A, Kuroki M, Saku K. Therapeutic Approaches to the Regulation of Metabolism of High-Density Lipoprotein. Circ J 2013; 77:2651-63. [DOI: 10.1253/circj.cj-12-1584] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Bo Zhang
- Department of Biochemistry, Fukuoka University School of Medicine
- The AIG Collaborative Research Institute of Cardiovascular Medicine, Fukuoka University School of Medicine
| | - Emi Kawachi
- Department of Cardiology, Fukuoka University School of Medicine
| | - Shin-ichiro Miura
- The AIG Collaborative Research Institute of Cardiovascular Medicine, Fukuoka University School of Medicine
- Department of Cardiology, Fukuoka University School of Medicine
- Department of Molecular Cardiovascular Therapeutics, Fukuoka University School of Medicine
| | - Yoshinari Uehara
- The AIG Collaborative Research Institute of Cardiovascular Medicine, Fukuoka University School of Medicine
- Department of Cardiology, Fukuoka University School of Medicine
- Department of Molecular Cardiovascular Therapeutics, Fukuoka University School of Medicine
| | - Akira Matsunaga
- The AIG Collaborative Research Institute of Cardiovascular Medicine, Fukuoka University School of Medicine
- Department of Laboratory Medicine, Fukuoka University School of Medicine
| | - Masahide Kuroki
- Department of Biochemistry, Fukuoka University School of Medicine
| | - Keijiro Saku
- The AIG Collaborative Research Institute of Cardiovascular Medicine, Fukuoka University School of Medicine
- Department of Cardiology, Fukuoka University School of Medicine
- Department of Molecular Cardiovascular Therapeutics, Fukuoka University School of Medicine
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14
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Combined Treatment with Pravastatin and Gemfibrozil in Patients with Refractory Familial Combined Hyperlipidaemia. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/bf03258465] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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15
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Eapen DJ, Kalra GL, Rifai L, Eapen CA, Merchant N, Khan BV. Raising HDL cholesterol in women. Int J Womens Health 2010; 1:181-91. [PMID: 21072287 PMCID: PMC2971704 DOI: 10.2147/ijwh.s5110] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Indexed: 01/21/2023] Open
Abstract
High-density lipoprotein cholesterol (HDL-C) concentration is essential in the determination of coronary heart disease (CHD) risk in women. This is especially true in the postmenopausal state, where lipid profiles and CHD risk mimic that of age-matched men. Thus, interventions designed to reduce CHD risk by raising HDL-C levels may have particular significance during the transition to menopause. This review discusses HDL-C-raising therapies and the role of HDL in the primary prevention of CHD in women. Lifestyle-based interventions such as dietary change, aerobic exercise regimens, and smoking cessation are initial steps that are effective in raising HDL-C, and available data suggest women respond similarly to men with these interventions. When combined with pharmacotherapy, the effects of these lifestyle alterations are further amplified. Though studies demonstrating gender-specific differences in therapy are limited, niacin continues to be the most effective agent in raising HDL-C levels, especially when used in combination with fibrate or statin therapy. Emerging treatments such as HDL mimetic therapy show much promise in further raising HDL-C levels and improving cardiovascular outcomes.
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Affiliation(s)
- Danny J Eapen
- Emory University School of Medicine, Atlanta, GA, USA
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16
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Abstract
The inverse correlation between high-density lipoprotein (HDL) levels and cardiovascular disease has driven several investigators to target the increase in this lipoprotein to prevent atherosclerosis and its complications. However, many reports have demonstrated that the use of HDL cholesterol (HDL-C) levels as a means to prevent and treat atherosclerosis has mainly resulted in negative outcomes. These findings may help to increase our knowledge of HDL metabolism and its protective effect. There is evidence that the mechanism by which HDL-C levels are raised has a great impact on cardiovascular outcomes. When the increase in HDL-C levels is secondary to greater synthesis, a strong beneficial effect in the prevention of cardiovascular diseases is observed. Even small increases in HDL-C levels induce a marked reduction in cardiovascular events; this has been observed during treatment with fibrates. In contrast, when the increase in HDL-C levels is secondary to a reduction in HDL catabolism, unexpectedly, the opposite effects are usually noted. Even dramatic increases in HDL-C levels are not associated with better cardiovascular outcomes. In fact, these increases have been related to a greater number of cardiovascular-related deaths. This became clear from the results of trials that tested inhibitors of cholesteryl ester transfer protein (CETP). We suggest that increases in reverse cholesterol transport are more important than HDL-C levels. Strong evidence is provided by individuals that express apolipoprotein (apo)A-I Milano. These individuals have extremely low HDL-C levels due to greater catabolism of the lipoprotein. However, reverse cholesterol transport is increased in these individuals and, as a consequence, they have a low incidence of cardiovascular diseases. We reinforce that, in clinical practice, the currently recommended levels of HDL-C should still be a major target to be aimed for. However, in the research field, we emphasize the need to look for other methods to improve reverse cholesterol transport, irrespective of HDL-C levels.
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Affiliation(s)
- Jose Oyama Leite
- Department of Nutritional Sciences, University of Connecticut, Storrs, Connecticut 06269-4017, USA.
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17
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Natarajan P, Ray KK, Cannon CP. High-Density Lipoprotein and Coronary Heart Disease. J Am Coll Cardiol 2010; 55:1283-99. [PMID: 20338488 DOI: 10.1016/j.jacc.2010.01.008] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 01/04/2010] [Accepted: 01/04/2010] [Indexed: 12/29/2022]
Affiliation(s)
- Pradeep Natarajan
- Department of Medicine, Cardiovascular Division, Brigham & Women's Hospital/Harvard Medical School, Boston, Massachusetts 02115, USA
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18
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Abstract
Gemfibrozil is long known for its ability to reduce the level of triglycerides in the blood circulation and to decrease the risk of hyperlipidemia. However, a number of recent studies reveal that apart from its lipid-lowering effects, gemfibrozil can also regulate many other signaling pathways responsible for inflammation, switching of T-helper cells, cell-to-cell contact, migration, and oxidative stress. In this review, we have made an honest attempt to analyze various biological activities of gemfibrozil and associated mechanisms that may help to consider this drug for different human disorders as primary or adjunct therapy.
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Affiliation(s)
- Avik Roy
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois 60612, USA
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19
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Shah A, Rader DJ, Millar JS. The effect of PPAR-alpha agonism on apolipoprotein metabolism in humans. Atherosclerosis 2009; 210:35-40. [PMID: 20005515 DOI: 10.1016/j.atherosclerosis.2009.11.010] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 09/30/2009] [Accepted: 11/09/2009] [Indexed: 11/27/2022]
Abstract
Metabolic syndrome, diabetes and obesity are frequently associated with hypertriglyceridemia, hypercholesterolemia and low HDL levels, a phenotype known as atherogenic dyslipidemia. Atherogenic dyslipidemia and hypertriglyceridemia are frequently treated with fibric acid derivatives which activate the nuclear receptor PPAR-alpha leading to reduce plasma triglycerides and an increase in HDL cholesterol levels. The mechanism by which activation of PPAR-alpha with fibrates improves the plasma lipid profile in patients with atherogenic dyslipidemia and hypertriglyceridemia has been examined in several small studies measuring lipoprotein kinetics. The results of these studies indicate that the changes in lipoprotein metabolism observed in response to fibrate treatment vary according to lipoprotein phenotype. In general, fibrates act to reduce VLDL apoB-100 through enhanced fractional catabolism (clearance) of VLDL apoB-100 with additional effects on reducing VLDL apoB-100 production. LDL apoB-100 levels generally decrease in response to fibrates due to increased LDL fractional catabolism except in those patients with high to very high plasma triglyceride levels (>400mg/dL). Fibrates also increase HDL apoA-I and apoA-II levels by enhancing apoA-I and apoA-II production, although this is partially counteracted by increasing fractional catabolism of these apolipoproteins. The potent and specific PPAR-alpha agonist LY518674, reduced VLDL apoB-100 levels through enhanced fractional catabolism similar to what is seen with fibrates. In contrast to fibrates, LY518674 did not change HDL apoA-I levels in response to due to an increased turnover of apoA-I where an increased fractional catabolic rate entirely counteracted the increase in apoA-I production. The changes in apoB metabolism in response to PPAR-alpha activation with fibrates and specific PPAR-alpha agonists would be expected to reduce the risk of cardiovascular disease. However, the benefit of the enhanced turnover of HDL apoA-I in response to PPAR-alpha activation remains to be determined.
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Affiliation(s)
- Ashish Shah
- University of Pennsylvania, Depts. of Medicine and Pharmacology, 652 BRB II/III, 421 Curie Blvd., Philadelphia, PA 19104, United States
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20
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21
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Abstract
UNLABELLED Cardiovascular disease remains a leading cause of mortality worldwide. As dyslipidemia increases cardiovascular disease risk, proper management of dyslipidemia is one means by which to decrease cardiovascular disease risk. This review focuses on dyslipidemia treatment utilizing fibrate therapy, which targets high trigylcerides, low HDL, and high small, dense LDL, while contrasting fibrate therapy with statin therapy and combined therapy. Studies were obtained using electronic search strategies, such as Medline and Cochrane Library. Sources selected were limited to those that discussed fibrates, statins, and combined therapy, with specific emphasis placed on sources that focused on fibrates. Selected studies were then assessed for quality via analysis of the study's methodology, results, and data. RESULTS of selected studies were then stratified using a rating system devised to determine the quality of results using the scientific evidence provided for them. Combination fibrate and statin therapy can be more effective in achieving optimal lipid levels than just fibrate or statin therapy alone without significant side effects as long as gemfibrozil is not used in therapy.
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22
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Millar JS, Duffy D, Gadi R, Bloedon LT, Dunbar RL, Wolfe ML, Movva R, Shah A, Fuki IV, McCoy M, Harris CJ, Wang MD, Howey DC, Rader DJ. Potent and selective PPAR-alpha agonist LY518674 upregulates both ApoA-I production and catabolism in human subjects with the metabolic syndrome. Arterioscler Thromb Vasc Biol 2008; 29:140-6. [PMID: 18988892 DOI: 10.1161/atvbaha.108.171223] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE The study of PPAR-alpha activation on apoA-I production in humans has been limited to fibrates, relatively weak PPAR-alpha agonists that may have other molecular effects. We sought to determine the effect of a potent and highly specific PPAR-alpha agonist, LY518674, on apoA-I, apoA-II, and apoB-100 kinetics in humans with metabolic syndrome and low levels of HDL cholesterol (C). METHODS AND RESULTS Subjects were randomized to receive LY518674 (100 microg) once daily (n=13) or placebo (n=15) for 8 weeks. Subjects underwent a kinetic study using a deuterated leucine tracer to measure apolipoprotein production and fractional catabolic rates (FCR) at baseline and after treatment. LY518674 significantly reduced VLDL-C (-38%, P=0.002) and triglyceride (-23%, P=0.002) levels whereas LDL-C and HDL-C levels were unchanged. LY518674 significantly reduced VLDL apoB-100 (-12%, P=0.01) levels, attributable to an increased VLDL apoB-100 FCR with no change in VLDL apoB-100 production. IDL and LDL apoB-100 kinetics were unchanged. LY518674 significantly increased the apoA-I production rate by 31% (P<0.0001), but this was accompanied by a 33% increase in the apoA-I FCR (P=0.002), resulting in no change in plasma apoA-I. There was a 71% increase in the apoA-II production rate (P<0.0001) accompanied by a 25% increase in the FCR (P<0.0001), resulting in a significant increase in plasma apoA-II. CONCLUSIONS Activation of PPAR-alpha with LY518674 (100 microg) in subjects with metabolic syndrome and low HDL-C increased the VLDL apoB-100 FCR consistent with enhanced lipolysis of plasma triglyceride. Significant increases in the apoA-I and apoA-II production rates were accompanied by increased FCRs resulting in no change in HDL-C levels. These data indicate a major effect of LY518674 on the production and clearance of apoA-I and HDL despite no change in the plasma concentration. The effect of these changes on reverse cholesterol transport remains to be determined.
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Affiliation(s)
- John S Millar
- Departments of Pharmacology, University of Pennsylvania, 652 BRB II/III, 421 Curie Blvd, Philadelphia, PA 19104, USA.
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23
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Klaunig JE, Babich MA, Baetcke KP, Cook JC, Corton JC, David RM, DeLuca JG, Lai DY, McKee RH, Peters JM, Roberts RA, Fenner-Crisp PA. PPARα Agonist-Induced Rodent Tumors: Modes of Action and Human Relevance. Crit Rev Toxicol 2008; 33:655-780. [PMID: 14727734 DOI: 10.1080/713608372] [Citation(s) in RCA: 433] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Widely varied chemicals--including certain herbicides, plasticizers, drugs, and natural products--induce peroxisome proliferation in rodent liver and other tissues. This phenomenon is characterized by increases in the volume density and fatty acid oxidation of these organelles, which contain hydrogen peroxide and fatty acid oxidation systems important in lipid metabolism. Research showing that some peroxisome proliferating chemicals are nongenotoxic animal carcinogens stimulated interest in developing mode of action (MOA) information to understand and explain the human relevance of animal tumors associated with these chemicals. Studies have demonstrated that a nuclear hormone receptor implicated in energy homeostasis, designated peroxisome proliferator-activated receptor alpha (PPARalpha), is an obligatory factor in peroxisome proliferation in rodent hepatocytes. This report provides an in-depth analysis of the state of the science on several topics critical to evaluating the relationship between the MOA for PPARalpha agonists and the human relevance of related animal tumors. Topics include a review of existing tumor bioassay data, data from animal and human sources relating to the MOA for PPARalpha agonists in several different tissues, and case studies on the potential human relevance of the animal MOA data. The summary of existing bioassay data discloses substantial species differences in response to peroxisome proliferators in vivo, with rodents more responsive than primates. Among the rat and mouse strains tested, both males and females develop tumors in response to exposure to a wide range of chemicals including DEHP and other phthalates, chlorinated paraffins, chlorinated solvents such as trichloroethylene and perchloroethylene, and certain pesticides and hypolipidemic pharmaceuticals. MOA data from three different rodent tissues--rat and mouse liver, rat pancreas, and rat testis--lead to several different postulated MOAs, some beginning with PPARalpha activation as a causal first step. For example, studies in rodent liver identified seven "key events," including three "causal events"--activation of PPARalpha, perturbation of cell proliferation and apoptosis, and selective clonal expansion--and a series of associative events involving peroxisome proliferation, hepatocyte oxidative stress, and Kupffer-cell-mediated events. Similar in-depth analysis for rat Leydig-cell tumors (LCTs) posits one MOA that begins with PPARalpha activation in the liver, but two possible pathways, one secondary to liver induction and the other direct inhibition of testicular testosterone biosynthesis. For this tumor, both proposed pathways involve changes in the metabolism and quantity of related hormones and hormone precursors. Key events in the postulated MOA for the third tumor type, pancreatic acinar-cell tumors (PACTs) in rats, also begin with PPARalpha activation in the liver, followed by changes in bile synthesis and composition. Using the new human relevance framework (HRF) (see companion article), case studies involving PPARalpha-related tumors in each of these three tissues produced a range of outcomes, depending partly on the quality and quantity of MOA data available from laboratory animals and related information from human data sources.
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Affiliation(s)
- James E Klaunig
- Indiana University School of Medicine, Indianapolis, IN, USA
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24
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Krause BR, Sliskovic DR, Ma Bocan T. Section Review—Cardiovascular & Renal: Emerging Therapies in Atherosclerosis. Expert Opin Investig Drugs 2008. [DOI: 10.1517/13543784.4.5.353] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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25
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Zurita JL, Repetto G, Jos A, Salguero M, López-Artíguez M, Cameán AM. Toxicological effects of the lipid regulator gemfibrozil in four aquatic systems. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2007; 81:106-15. [PMID: 17169444 DOI: 10.1016/j.aquatox.2006.11.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 11/09/2006] [Accepted: 11/14/2006] [Indexed: 05/13/2023]
Abstract
Gemfibrozil is a lipid-regulating agent widely used in patients at risk of coronary disease. Pharmaceutical products, such as gemfibrozil, are found in municipal effluents and represent a major source of contamination. To date, there is little available information about the adverse effects of gemfibrozil in aquatic organisms. For this reason, the toxic effects were investigated using model systems from four trophic levels. The most sensitive system was the immobilization of Daphnia magna, with a non-observed adverse effect level of 30 microM and a mean effective concentration of 120 microM after 72 h, followed by the inhibition of bioluminescence of Vibrio fischeri, the hepatoma fish cell line PLHC-1 line and the inhibition of the growth of Chlorella vulgaris. Although protein content, neutral red uptake, methylthiazol metabolization and lysosomal function were reduced in PLHC-1 cells, stimulations were observed for lysosomal function, metallothionein levels and succinate dehydrogenase, glucose-6-phosphate dehydrogenase and acetylcholinesterase activities. No changes were observed in ethoxyresorufin-O-deethylase activity. The main morphological alterations were hydropic degeneration and loss of cells. Modulation studies on gemfibrozil toxicity were also carried out. General antioxidants and calcium chelators did not modify the toxicity of gemfibrozil, whereas a Fe(III) chelator, a membrane permeable sulphydryl-protecting compound and glutathione level modifying agents did change the toxicity. One of the possible mechanisms of gemfibrozil toxicity seems to be the binding to sulphydryl groups, including those of glutathione. According to the result, gemfibrozil should be classified as harmful to aquatic organisms. However, comparing the concentrations in water and the toxicity quantified in the assayed systems, gemfibrozil is not expected to represent acute risk to the aquatic biota.
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Affiliation(s)
- Jorge L Zurita
- National Institute of Toxicology and Forensic Sciences. Av. Dr Fedriani s/n, 41009 Seville, Spain
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26
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Luoma PV. Cytochrome P450--physiological key factor against cholesterol accumulation and the atherosclerotic vascular process. Ann Med 2007; 39:359-70. [PMID: 17701478 DOI: 10.1080/07853890701379767] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In the early 1960s liver cytochrome P450 (P450) was known as an enzyme in drug metabolism. By the late 1970s, P450 induction was associated with elevation of plasma high-density lipoprotein cholesterol and apolipoprotein AI indicating a reduced risk of atherosclerotic disease. Later on, 57 human P450 genes have been identified. One P450 enzyme participates in cholesterol synthesis, and several others catabolize it to oxysterols and other metabolites. Oxysterols are physiological ligands specific for liver X receptors (LXRs) in the activation of ATP-binding cassette (ABC) transporter and other cholesterol-lowering genes. Elevation of cholesterol leads to an endogenous induction of P450 and consequently to enhanced generation of oxysterols and activation of genes coding proteins which efflux cholesterol out of cells, transport it to the liver, catabolize and excrete cholesterol into bile, and prevent absorption of cholesterol in the intestine in the processes that maintain cellular cholesterol homeostasis and protect arteries from atherosclerosis. Peroxisome proliferator-activated receptors (PPARs) co-operate with LXRs and ABC transporters in cholesterol regulation. Secretion of oxysterol is a direct pathway for cellular cholesterol elimination. Several compounds induce P450 and other genes regulating cholesterol balance and prevent or regress atherosclerosis, whereas inhibition of P450 blocks oxidative reactions, promotes cholesterol accumulation, and enhances the atherosclerotic vascular process.
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Affiliation(s)
- Pauli V Luoma
- Institute of Biomedicine, Pharmacology, University of Helsinki, Finland.
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27
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Rashid S, Patterson BW, Lewis GF. Thematic review series: patient-oriented research. What have we learned about HDL metabolism from kinetics studies in humans? J Lipid Res 2006; 47:1631-42. [PMID: 16685079 DOI: 10.1194/jlr.r600008-jlr200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Plasma measurements of lipids, lipoproteins, and apolipoproteins provide information on the static levels of these fractions without providing key information on the dynamic fluxes of lipoproteins in the circulation. Kinetics studies, in contrast, provide additional information on the production and clearance rates of lipoproteins and the flow of lipids and apolipoproteins through lipoprotein fractions. This information is crucial in accurately delineating the metabolism of HDL in plasma, because plasma concentrations of HDL are the net result of the de novo production and catabolism of HDL as well as the recycling of HDL particles and the contribution to HDL from components of other lipoproteins. Studies aimed at measuring the metabolism of HDL particles have shown that HDL metabolism in vivo is complex and consists of multiple components. Kinetics studies provide a window into the metabolism of HDL, allowing us to better understand the mechanisms of HDL decrease in human conditions and the functionality of HDL particles. Here, we review the progress in our understanding of HDL metabolism derived from in vivo kinetics studies, focusing primarily on studies in humans but also reviewing key studies in animal models.
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Affiliation(s)
- Shirya Rashid
- Department of Cardiology, McGill University, Montreal, Canada
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28
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Abstract
There is a distinct inverse relationship between high-density lipoprotein cholesterol (HDL-C) and cardiovascular disease risk. HDL-C mediates cholesterol efflux from the vasculature and promotes anti-oxidant, anti-inflammatory, and anti-thrombotic effects. There are multiple lifestyle and therapeutic interventions that raise HDL-C, and there is increasing evidence that these interventions improve cardiovascular outcomes. Recent findings regarding the role of HDL-C in cholesterol metabolism offer new strategies designed to target atherosclerosis. This review highlights the utility of existing HDL-C-raising strategies and examines new potential therapies.
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Affiliation(s)
- Jeffrey T Kuvin
- Division of Cardiology, Department of Medicine, Tufts-New England Medical Center, Tufts University School of Medicine Boston, Massachusettes 0211, USA.
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29
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Després JP, Lemieux I, Robins SJ. Role of fibric acid derivatives in the management of risk factors for coronary heart disease. Drugs 2005; 64:2177-98. [PMID: 15456334 DOI: 10.2165/00003495-200464190-00003] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Although elevated low-density lipoprotein (LDL)-cholesterol is a well established coronary heart disease (CHD) risk factor, the ability to adequately discriminate high-risk individuals by this risk factor alone is limited and other metabolic risk variables are known to modulate CHD risk. For instance, it has been reported that the cluster of metabolic disturbances observed among individuals with abdominal obesity, the so-called metabolic syndrome, is associated with a substantially increased risk of CHD. Among the features of the dyslipidaemic profile observed in these individuals, the high triglyceride-low high-density lipoprotein (HDL)-cholesterol dyslipidaemia is predictive of an elevated risk of CHD. Fibric acid derivatives (fibrates) have been used in clinical practice for more than 2 decades as a class of agents known to decrease triglyceride levels while substantially increasing HDL-cholesterol levels, with a limited but significant additional lowering effect on LDL-cholesterol levels. Although the clinical benefits of HMG-CoA reductase inhibitors (statins) have been well documented by primary and secondary prevention trials that justify their widespread use, it was not until the publication of the VA-HIT (Veterans Affairs High-Density Lipoprotein Intervention Trial) that the relevance of identifying HDL-cholesterol as a therapeutic target to reduce the risk of recurrent CHD events was finally confirmed. The clinical benefits of fibrate therapy are especially important in the subpopulation of patients with low HDL-cholesterol levels with the metabolic syndrome, particularly in patients with type 2 diabetes mellitus or in abdominally obese, hyperinsulinaemic patients. Evidence also suggests that there is a 'fibrate effect' that mediates the reduction in CHD risk beyond the favourable impact of these agents on HDL-cholesterol levels. This last notion is consistent with the pleiotropic effects of fibrates which are known to be related to their mechanisms of action. Through peroxisome proliferator-activated alpha-receptors, fibrates have a significant impact on the synthesis of several apolipoproteins (apo) and enzymes of lipoprotein metabolism as well as on the expression of several genes involved in fibrinolysis and inflammation. Fibrate therapy has been reported to decrease apo CIII levels (a powerful inhibitor of lipoprotein lipase) and increase apo AI levels, as well as to increase lipoprotein lipase activity. Such changes contribute to improve the catabolism of triglyceride-rich lipoproteins, leading to a substantial increase in HDL-cholesterol levels accompanied by a shift in the size and density of LDL particles (from small, dense LDL particles to larger, more buoyant cholesteryl ester-rich LDL). It is proposed that some of these pleiotropic effects could explain some of the clinical benefits of fibrate therapy beyond its HDL-raising properties, particularly among patients with abdominal obesity, hyperinsulinaemia or type 2 diabetes with both low HDL- and low/normal LDL-cholesterol levels.
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30
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Zhang B, Tomura H, Kuwabara A, Kimura T, Miura SI, Noda K, Okajima F, Saku K. Correlation of high density lipoprotein (HDL)-associated sphingosine 1-phosphate with serum levels of HDL-cholesterol and apolipoproteins. Atherosclerosis 2005; 178:199-205. [PMID: 15585219 DOI: 10.1016/j.atherosclerosis.2004.08.024] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2004] [Revised: 07/06/2004] [Accepted: 08/20/2004] [Indexed: 11/16/2022]
Abstract
BACKGROUND Extracellular sphingosine 1-phosphate (S1P) has been shown to contribute to the action of high density lipoprotein (HDL) on endothelial and smooth muscle cells. We examined the relationship of lipoprotein-associated S1P concentrations with cholesterol (C) and apolipoprotein (apo) contents of lipoprotein and lipoprotein subfractions characterized by capillary isotachophoresis (cITP). METHODS Blood samples were drawn from 16 volunteers. S1P concentrations were quantified by bioassay based on the ability of S1P to stimulate its receptor. cITP was performed using plasma that had been prestained with NBD-ceramide. RESULTS In plasma, S1P was concentrated in HDL and associated with LDL at a much lower concentration. HDL-S1P was the major determinant of the plasma S1P concentration. HDL-S1P was strongly and positively (p<0.001) correlated with serum levels of HDL-C (r=0.82), apo A-I (r=0.91) and apo A-II (r=0.92). HDL-S1P was strongly and positively (p<0.01) correlated with the apo A-I- and apo A-I/apo A-II-containing cITP HDL subfractions [fast HDL-C (r=0.66) and intermediate HDL-C (r=0.80)], but was not significantly correlated with apo E-containing slow HDL, suggesting that S1P is associated with both apo A-I HDL and apo A-I/A-II HDL. LDL-S1P was positively correlated (p<0.01) with levels of LDL-C (r=0.65) and apo B (r=0.85). CONCLUSION Lipoprotein-associated S1P was related to the lipoprotein composition of cholesterol and apolipoproteins, suggesting that extracellular S1P may play different roles depending on the particles with which it is associated.
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Affiliation(s)
- Bo Zhang
- Department of Cardiology, Fukuoka University School of Medicine, 7-45-1 Nanakuma Jonan-ku, Fukuoka 814-0180, Japan
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31
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Chan DC, Barrett PHR, Watts GF. Lipoprotein transport in the metabolic syndrome: pathophysiological and interventional studies employing stable isotopy and modelling methods. Clin Sci (Lond) 2004; 107:233-49. [PMID: 15225143 DOI: 10.1042/cs20040109] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Revised: 05/19/2004] [Accepted: 06/30/2004] [Indexed: 01/03/2023]
Abstract
The accompanying review in this issue of Clinical Science [Chan, Barrett and Watts (2004) Clin. Sci. 107, 221–232] presented an overview of lipoprotein physiology and the methodologies for stable isotope kinetic studies. The present review focuses on our understanding of the dysregulation and therapeutic regulation of lipoprotein transport in the metabolic syndrome based on the application of stable isotope and modelling methods. Dysregulation of lipoprotein metabolism in metabolic syndrome may be due to a combination of overproduction of VLDL [very-LDL (low-density lipoprotein)]-apo (apolipoprotein) B-100, decreased catabolism of apoB-containing particles and increased catabolism of HDL (high-density lipoprotein)-apoA-I particles. These abnormalities may be consequent on a global metabolic effect of insulin resistance, partly mediated by depressed plasma adiponectin levels, that collectively increases the flux of fatty acids from adipose tissue to the liver, the accumulation of fat in the liver and skeletal muscle, the hepatic secretion of VLDL-triacylglycerols and the remodelling of both LDL (low-density lipoprotein) and HDL particles in the circulation. These lipoprotein defects are also related to perturbations in both lipolytic enzymes and lipid transfer proteins. Our knowledge of the pathophysiology of lipoprotein metabolism in the metabolic syndrome is well complemented by extensive cell biological data. Nutritional modifications may favourably alter lipoprotein transport in the metabolic syndrome by collectively decreasing the hepatic secretion of VLDL-apoB and the catabolism of HDL-apoA-I, as well as by potentially increasing the clearance of LDL-apoB. Several pharmacological treatments, such as statins, fibrates or fish oils, can also correct the dyslipidaemia by diverse kinetic mechanisms of action, including decreased secretion and increased catabolism of apoB, as well as increased secretion and decreased catabolism of apoA-I. The complementary mechanisms of action of lifestyle and drug therapies support the use of combination regimens in treating dyslipoproteinaemia in subjects with the metabolic syndrome.
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Affiliation(s)
- Dick C Chan
- Lipoprotein Research Unit, School of Medicine and Pharmacology, University of Western Australia, Perth, WA 6847
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Abstract
There is a large body of evidence demonstrating an inverse correlation between circulating levels of high-density lipoprotein (HDL) cholesterol and cardiovascular disease risk. For every 1-mg/dL increase in HDL, it is estimated that the risk of cardiovascular events decreases by 2% to 3%. HDL is one of many factors that contribute to the regulation of the atherosclerotic process. HDL mediates reverse cholesterol transport and exhibits numerous beneficial properties, including antioxidant, antiinflammatory, and antithrombotic effects on the vasculature. Recent studies have expanded our understanding of the vasoprotective mechanisms of HDL to include enhanced nitric oxide production and improved endothelium-dependent relaxation. Progress has also been made in determining the molecular mechanisms that mediate reverse cholesterol transport. Recently published National Cholesterol Education Program Adult Treatment Panel guidelines have broadened the definition of low levels of HDL and encourage more aggressive screening and treatment of lipid abnormalities. Several therapeutic interventions can augment HDL concentrations, and there is increasing evidence that these interventions improve cardiovascular outcomes. Research focusing on defining the molecular roles of HDL will likely identify potential therapeutic targets for decreasing the incidence and progression of coronary heart disease. This review highlights the role of HDL in coronary heart disease, from basic mechanisms of action to recent clinical trial results.
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Affiliation(s)
- Christine E Young
- Department of Medicine/Division of Cardiology, Tufts-New England Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
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Chan DC, Barrett PHR, Watts GF. Lipoprotein kinetics in the metabolic syndrome: pathophysiological and therapeutic lessons from stable isotope studies. Clin Biochem Rev 2004; 25:31-48. [PMID: 18516204 PMCID: PMC1853360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Dyslipoproteinaemia is a cardinal feature of the metabolic syndrome that accelerates atherosclerosis. It is usually characterised by high plasma concentrations of triglyceride-rich and apolipoprotein (apo) B-containing lipoproteins, with depressed concentrations of high-density lipoprotein (HDL). Dysregulation of lipoprotein metabolism in these subjects may be due to a combination of overproduction of very-low-density lipoprotein (VLDL) apoB-100, decreased catabolism of apoB-containing particles, and increased catabolism of HDL apoA-I particles. These abnormalities may be consequent on a global metabolic effect of insulin resistance that increases the flux of fatty acids from adipose tissue to the liver, the accumulation of fat in the liver, the increased hepatic secretion of VLDL-triglycerides and the remodelling of both low-density lipoprotein (LDL) and HDL particles in the circulation; perturbations in lipolytic enzymes and lipid transfer proteins contribute to the dyslipidaemia. Our in vivo understanding of the kinetic defects in lipoprotein metabolism in the metabolic syndrome has been chiefly achieved by ongoing developments in the use of stable isotope tracers and mathematical modelling. Knowledge of the pathophysiology of lipoprotein metabolism in the metabolic syndrome is well complemented by extensive cell biological data. Nutritional modifications and increased physical exercise may favourably alter lipoprotein transport in the metabolic syndrome by collectively decreasing the hepatic secretion of VLDL-apoB and the catabolism of HDL apoA-I, as well as by increasing the clearance of LDL-apoB. Pharmacological treatments, such as statins, fibrates or fish oils, can also correct the dyslipidaemia by several mechanisms of action including decreased secretion and increased catabolism of apoB, as well as increased secretion and decreased catabolism of apoA-I. The complementary mechanisms of action of lifestyle and drug therapies support the use of combination regimens to treat dyslipidaemia in the metabolic syndrome.
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Affiliation(s)
- Dick C Chan
- Lipoprotein Research Unit, School of Medicine and Pharmacology, University of Western Australia and The Western Australian Institute for Medical Research, Perth, WA 6847, Australia
| | - P Hugh R Barrett
- Lipoprotein Research Unit, School of Medicine and Pharmacology, University of Western Australia and The Western Australian Institute for Medical Research, Perth, WA 6847, Australia
| | - Gerald F Watts
- Lipoprotein Research Unit, School of Medicine and Pharmacology, University of Western Australia and The Western Australian Institute for Medical Research, Perth, WA 6847, Australia
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Shimoji E, Zhang B, Fan P, Saku K. Inhibition of cholesteryl ester transfer protein increases serum apolipoprotein (apo) A-I levels by increasing the synthesis of apo A-I in rabbits. Atherosclerosis 2004; 172:247-57. [PMID: 15019534 DOI: 10.1016/j.atherosclerosis.2003.09.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2003] [Revised: 07/23/2003] [Accepted: 09/17/2003] [Indexed: 11/25/2022]
Abstract
BACKGROUND Inhibition of cholesteryl ester transfer protein (CETP) is an effective way to increase HDL levels in animals and humans. The effects of a CETP inhibitor, JTT-705, on the in vivo kinetics of apolipoprotein (apo) A-I and apo A-I gene expression in the liver and intestine were investigated. METHODS Japanese White rabbits were randomly fed normal rabbit chow LRC-4 (n=10, control) or a food admixture of LRC-4 and 0.75% JTT-705 (n=10, treated) for 7 months. An in vivo kinetics study of apo A-I was performed by injecting rabbit 125I-apo A-I, and apo A-I mRNA levels were quantified by RT-PCR. RESULTS JTT-705 significantly inhibited CETP activities, increased serum levels of HDL-cholesterol (C), HDL2-C, HDL-phospholipid, and apo A-I, and decreased HDL-triglyceride levels. The synthetic rate of apo A-I was higher in the treated rabbits than in control rabbits (13.7 +/- 2.6 versus 9.5 +/- 1.3 mg/kg per day, P < 0.05), while the fractional catabolic rate was similar in the two groups. JTT-705 increased apo A-I mRNA levels in the liver without affecting those in the intestine. CONCLUSION Inhibition of CETP activity by JTT-705 increases HDL levels by increasing the synthesis of apo A-I, suggesting that it could be a promising therapeutic approach for atherosclerosis.
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Affiliation(s)
- Eiso Shimoji
- Department of Cardiology, Fukuoka University School of Medicine, 7-45-1 Nanakuma Jonan-ku, Fukuoka 814-0180, Japan
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Bilz S, Wagner S, Schmitz M, Bedynek A, Keller U, Demant T. Effects of atorvastatin versus fenofibrate on apoB-100 and apoA-I kinetics in mixed hyperlipidemia. J Lipid Res 2004; 45:174-85. [PMID: 14523053 DOI: 10.1194/jlr.m300309-jlr200] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Kinetics of apo B and apo AI were assessed in 8 patients with mixed hyperlipidemia at baseline and after 8 weeks of atorvastatin 80 mg q.d. and micronised fenofibrate 200 mg q.d. in a cross-over study. Both increased hepatic production and decreased catabolism of VLDL accounted for elevated cholesterol and triglyceride concentrations at baseline. Atorvastatin significantly decreased triglyceride, total, VLDL and LDL cholesterol and apo B concentrations (-65%, -36%, -57%, -40% and -33%, respectively, P<0.05). Kinetic analysis revealed that atorvastatin stimulated the catabolism of apo B containing lipoproteins, enhanced the delipidation of VLDL1 and decreased VLDL1 production. Fenofibrate lowered triglycerides and VLDL cholesterol (-57% and -64%, respectively, P<0.05) due to enhanced delipidation of VLDL1 and VLDL2 and increased VLDL1 catabolism. Changes of HDL particle composition accounted for the increase of HDL cholesterol during atorvastatin and fenofibrate (18% and 23%, P<0.01). Only fenofibrate increased apo AI concentrations through enhanced apo AI synthesis (45%, P<0.05). We conclude that atorvastatin exerts additional beneficial effects on the metabolism of apo B containing lipoproteins unrelated to an increase in LDL receptor activity. Fenofibrate but not atorvastatin increases apo AI production and plasma turnover.
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Affiliation(s)
- Stefan Bilz
- Division of Endocrinology, Diabetology, and Clinical Nutrition, University Hospital Basel, Basel, Switzerland
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Calza L, Manfredi R, Farneti B, Chiodo F. Incidence of hyperlipidaemia in a cohort of 212 HIV-infected patients receiving a protease inhibitor-based antiretroviral therapy. Int J Antimicrob Agents 2003; 22:54-9. [PMID: 12842328 DOI: 10.1016/s0924-8579(03)00100-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Two hundred and twelve HIV-positive patients who started a new protease inhibitor (PI)-based antiretroviral regimen between January 1998 and December 2000 in our tertiary care centre were prospectively followed-up during a 12-month study period, in order to assess the incidence of hyperlipidaemia and related clinical adverse events. At the end of 1-year follow-up, PI-containing antiretroviral treatment led to a statistically significant increase in serum triglyceride levels (P<0.005) and total and LDL-cholesterol levels (P<0.05). The overall incidence of hypertriglyceridaemia and hypercholesterolaemia was 38.2 and 25%, respectively. The incidence of increased serum triglyceride levels was significantly higher in patients treated with ritonavir (66.6%) or lopinavir/ritonavir (60.7%), compared with other PIs (P<0.04). Clinical adverse events possibly related to the hyperlipidaemia (such as cardiovascular diseases or acute pancreatitis) were not observed during the entire 12 months study period. In conformity with other previously published studies, the very high incidence of hyperlipidaemia during a PI-based therapy recognised in our work raises a big concern about its potential clinico-pathological consequences and the most convenient pharmacological management of these metabolic imbalances.
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Affiliation(s)
- Leonardo Calza
- Department of Clinical and Experimental Medicine, Section of Infectious Diseases, University of Bologna, S. Orsola Hospital, via G. Massarenti 11, I-40138 Bologna, Italy.
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Després JP, Lemieux I, Pascot A, Alméras N, Dumont M, Nadeau A, Bergeron J, Prud'homme D. Gemfibrozil reduces plasma C-reactive protein levels in abdominally obese men with the atherogenic dyslipidemia of the metabolic syndrome. Arterioscler Thromb Vasc Biol 2003; 23:702-3. [PMID: 12692010 DOI: 10.1161/01.atv.0000062990.62034.64] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Zhang B, Shimoji E, Tanaka H, Saku K. Evaluation of apolipoprotein A-I kinetics in rabbits in vivo using in situ and exogenous radioiodination methods. Lipids 2003; 38:209-18. [PMID: 12784860 DOI: 10.1007/s11745-003-1053-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The kinetics of in vivo clearance of apolipoprotein (apo) A-I radioiodinated by the iodine monochloride (ICI) method of McFarlane [McFarlane, A.S. (1958) Efficient Trace-Labelling of Proteins with Iodine, Nature 182, 53] as modified by Bilheimer and co-workers [Bilheimer, D.W., Eisenberg, S., and Levy, R.I. (1972) The Metabolism of Very Low Density Lipoprotein Proteins. I. Preliminary in vitro and in vivo Observations, Biochim. Biophys. Acta 260, 212-221] and by using the IODO Beads Iodination Reagent were evaluated in rabbits. Both human apoA-I and rabbit HDL radioiodinated by the IODO Beads Iodination Reagent were cleared faster from plasma of rabbits than those radiolabeled by the ICI method. However, the different radiolabeling procedures in the ICI method, i.e., apoA-I radiolabeled either exogenously or in situ as a part of intact HDL, were not associated with a significant difference in the in vivo kinetics of apoA-I in rabbits if apoA-I was prepared by the guanidine HCI method and used fresh. 125I-ApoA-I subjected to delipidation and lyophilization was cleared only slightly faster from the plasma of rabbits than fresh 125I-apoA-I. We also found that apoA-I separated by the guanidine HCI method and used fresh was cleared faster from the plasma of rabbits when it was injected as free apoA-I without adding serum albumin or after in vitro incubation with rabbit HDL than when injected after reassociation with rabbit plasma. We conclude that the ICI method is a more appropriate radioiodination method for studying the in vivo kinetics of HDL than the IODO Beads Iodination Reagent and that the in vitro incubation conditions before injection are important factors that affect the in vivo kinetics of apo A-I.
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Affiliation(s)
- Bo Zhang
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka 814-0180, Japan
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Watts GF, Barrett PHR, Ji J, Serone AP, Chan DC, Croft KD, Loehrer F, Johnson AG. Differential regulation of lipoprotein kinetics by atorvastatin and fenofibrate in subjects with the metabolic syndrome. Diabetes 2003; 52:803-11. [PMID: 12606523 DOI: 10.2337/diabetes.52.3.803] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The metabolic syndrome is characterized by insulin resistance and abnormal apolipoprotein AI (apoAI) and apolipoprotein B-100 (apoB) metabolism that may collectively accelerate atherosclerosis. The effects of atorvastatin (40 mg/day) and micronised fenofibrate (200 mg/day) on the kinetics of apoAI and apoB were investigated in a controlled cross-over trial of 11 dyslipidemic men with the metabolic syndrome. ApoAI and apoB kinetics were studied following intravenous d(3)-leucine administration using gas-chromatography mass spectrometry with data analyzed by compartmental modeling. Compared with placebo, atorvastatin significantly decreased (P < 0.001) plasma concentrations of cholesterol, triglyceride, LDL cholesterol, VLDL apoB, intermediate-density lipoprotein (IDL) apoB, and LDL apoB. Fenofibrate significantly decreased (P < 0.001) plasma triglyceride and VLDL apoB and elevated HDL(2) cholesterol (P < 0.001), HDL(3) cholesterol (P < 0.01), apoAI (P = 0.01), and apoAII (P < 0.001) concentrations, but it did not significantly alter LDL cholesterol. Atorvastatin significantly increased (P < 0.002) the fractional catabolic rate (FCR) of VLDL apoB, IDL apoB, and LDL apoB but did not affect the production of apoB in any lipoprotein fraction or in the turnover of apoAI. Fenofibrate significantly increased (P < 0.01) the FCR of VLDL, IDL, and LDL apoB but did not affect the production of VLDL apoB. Relative to placebo and atorvastatin, fenofibrate significantly increased the production (P < 0.001) and FCR (P = 0.016) of apoAI. Both agents significantly lowered plasma triglycerides and apoCIII concentrations, but only atorvastatin significantly lowered (P < 0.001) plasma cholesteryl ester transfer protein activity. Neither treatment altered insulin resistance. In conclusion, these differential effects of atorvastatin and fenofibrate on apoAI and apoB kinetics support the use of combination therapy for optimally regulating dyslipoproteinemia in the metabolic syndrome.
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Affiliation(s)
- Gerald F Watts
- Lipoprotein Research Unit, Department of Medicine, University of Western Australia, Royal Perth Hospital, Box X2213 GPO, Perth, WA 6847, Australia.
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40
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Abstract
Plasma levels of high-density lipoprotein-cholesterol (HDL-C) are a powerful independent cardiovascular risk factor, bearing an inverse relationship with atherosclerotic cardiovascular disease (with risk rising sharply when levels are <1.04 mmol/L). Apart from its protective role in atherosclerosis, HDL-C increases fibrinolysis, is an antioxidant to low density lipoprotein-cholesterol (LDL-C), and decreases platelet aggregability. Up to a third of patients with atherosclerotic cardiovascular disease have 'desirable' plasma levels of total cholesterol but low HDL-C levels. Benefits of treating low plasma HDL-C levels were clearly demonstrated in the Veterans Affairs HDL Intervention Trial (VA-HIT) where gemfibrozil reduced nonfatal infarcts and coronary deaths by 22%. This was achieved by a 6% increase in plasma HDL-C levels, and a 24.5% decrease in plasma levels of triglycerides, without any significant decrease in LDL-C levels. Multivariate analyses revealed the rise in plasma HDL-C levels after treatment, but not decreases in plasma levels of triglycerides or LDL-C, predicted coronary artery disease events. The typical patient under consideration in this article is one with plasma levels of HDL-C <1 mmol/L, LDL-C <3.37 mmol/L [either receiving therapeutic lifestyle changes or or LDL-C-lowering therapy comprising a hydroxymethylglutaryl coenzyme-A (HMG-CoA) reductase inhibitor or bile acid sequestrant] and fasting triglycerides <2.26 mmol/L. We propose this dyslipidemia be classified as Type VI phenotype following the Frederickson and Lees classification. High-risk patients (with >/=2 risk factors for atherosclerotic cardiovascular disease, or 10-year cardiovascular risk >20%), patients with established atherosclerotic cardiovascular disease, or type 2 diabetes mellitus, or metabolic syndrome should receive pharmacotherapy. Plasma HDL-C levels >1.16 mmol/L may be considered optimal and between 1 and 1.16 mmol/L as desirable. Fibric acid derivatives, nicotinic acid, HMG-CoA reductase inhibitors, estrogens, and ethanol (not recommended as therapy) increase plasma HDL-C levels. Nicotinic acid is the most potent agent and recent reports indicate that, in contrast to gemfibrozil, it selectively increases antiatherogenic HDL subfraction, lipoprotein (Lp) AI (without apolipoprotein AII), in patients with low plasma HDL-C levels. An extended-release formulation, administered once daily, has improved the tolerability of nicotinic acid. Recent evidence also indicates that nicotinic acid may effectively correct dyslipidemia in patients with diabetes mellitus without significantly compromising glycemic control. Fibric acid derivatives and estrogen raise plasma HDL-C levels by different mechanisms of action, and these agents may be used with nicotinic acid. Combination therapy (especially HMG-CoA reductase inhibitor and nicotinic acid) should be considered in patients with atherosclerotic cardiovascular disease and low plasma HDL-C levels.
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Affiliation(s)
- Moti L Kashyap
- Department of Veterans Affairs Healthcare System, Long Beach, California, USA.
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41
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Zhu D, Ganji SH, Kamanna VS, Kashyap ML. Effect of gemfibrozil on apolipoprotein B secretion and diacylglycerol acyltransferase activity in human hepatoblastoma (HepG2) cells. Atherosclerosis 2002; 164:221-8. [PMID: 12204791 DOI: 10.1016/s0021-9150(02)00060-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mechanism of action of a widely used drug gemfibrozil to reduce triglycerides (TG) and apolipoprotein B (apo B) is incompletely understood. Using human hepatoblastoma (HepG2) cells, we examined the effect of gemfibrozil on apo B secretion and TG synthesis catalyzed by diacylglycerol acyltransferase (DGAT), primary processes associated with the secretion of LDL. Gemfibrozil significantly decreased apo B secretion by HepG2 cells. It decreased oleate-induced stimulation of apo B secretion, suggesting that gemfibrozil-mediated inhibition of apo B secretion may be dependent on the synthesis of TG catalyzed by DGAT. Pre-incubation of HepG2 cells with gemfibrozil (200-400 micromol/l for 48 h) significantly inhibited microsomal DGAT activity. When added directly to the DGAT assay system containing control microsomes, gemfibrozil significantly inhibited the activity of DGAT by 14-25%. Gemfibrozil (200-400 micromol/l) inhibited TG synthesis by 47-50% as measured by the incorporation of 3H-oleic acid into TG. The data indicate that gemfibrozil inhibits DGAT activity resulting in decreased synthesis of TG and its availability for apo B lipidation rendering it susceptible to intracellular apo B degradation leading to the decreased secretion. These in-vitro data suggest a novel additional mechanism by which gemfibrozil lowers plasma TG and atherogenic apo B lipoproteins in dyslipidemic patients.
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Affiliation(s)
- Daming Zhu
- Cholesterol Research Center, Long Beach Department of Veterans Affairs Healthcare System and University of California, Irvine, 5901 E. Seventh Street (11-111I), Long Beach, CA 90822, USA
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42
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Affiliation(s)
- Lucian Saucan
- From the Carl T. Hayden VA Medical Center, Phoenix, Ariz
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43
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Sakai T, Kamanna VS, Kashyap ML. Niacin, but not gemfibrozil, selectively increases LP-AI, a cardioprotective subfraction of HDL, in patients with low HDL cholesterol. Arterioscler Thromb Vasc Biol 2001; 21:1783-9. [PMID: 11701466 DOI: 10.1161/hq1001.096624] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Evidence indicates that the high density lipoprotein (HDL) subfraction containing apolipoprotein A-I without apolipoprotein AII (LP-AI) is more antiatherogenic than HDL particles containing apolipoprotein A-I and apolipoprotein A-II (LP-AI+AII). This study examined the effect of extended-release niacin (niacin-ER) and gemfibrozil on LP-AI and LP-AI+AII particles in patients with low levels of HDL cholesterol (HDL-C). Mechanisms by which these agents modulate HDL particles were investigated by in vitro studies using human hepatoblastoma (Hep G2) cells. A total of 139 patients with low HDL-C (</=40 mg/dL) were randomized to niacin-ER or gemfibrozil in a multicenter double-blind trial. Patients were dose-escalated with once-nightly niacin-ER (1 to 2 g) or gemfibrozil (1.2 g) for 19 weeks. Niacin-ER had a greater effect in raising HDL-C and apolipoprotein A-I levels than did gemfibrozil. Niacin-ER at 1- and 2-g doses increased LP-AI levels by 8.7+/-4.0% (P=0.033) and 24.0+/-4.4% (P<0.001), respectively. Gemfibrozil had no consistent effect on LP-AI levels. LP-AI+AII levels increased 5% to 8% by both agents. In vitro studies showed that niacin, but not gemfibrozil, selectively decreased the uptake of (125)I-labeled LP-AI holoparticles by Hep G2 cells. The uptake of [(3)H]cholesterol ester was approximately 75% greater from LP-AI versus LP-AI+AII particles, but neither niacin nor gemfibrozil affected cholesterol ester uptake. These data indicate that unlike gemfibrozil, niacin selectively increases LP-AI compared with LP-AI+AII particle concentration in patients with low HDL-C levels. The mechanism of action of increased LP-AI concentration appears to be mediated by decreased hepatic removal of LP-AI particles, which are more efficient in reverse cholesterol transport, thus suggesting an additional mechanism by which niacin mediates its antiatherogenic properties.
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Affiliation(s)
- T Sakai
- Cholesterol Research Center, Department of Veterans Affairs Healthcare System, Long Beach, California, USA
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Zhang B, Saku K, Ohta T. In vivo metabolism of HDL, apo A-I, and lp A-I, and function of HDL--a clinical perspective. J Atheroscler Thromb 2001; 7:59-66. [PMID: 11426583 DOI: 10.5551/jat1994.7.59] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Serum levels of high density lipoprotein cholesterol (HDL-C) are inversely correlated with coronary heart disease (CHD). Kinetic studies indicate that the mechanism for the variation in HDL levels associated with various pathophysiologic states includes changes in the fractional catabolic rate (FCR) and/or the synthesis rate of HDL and its major proteins apolipoprotein (apo) A-I and apo A-II. The antiatherogenic effects of HDL are thought to be mainly due to its role in reverse cholesterol transport. HDL is an assembly of heterogeneous particles. HDL enlarges when it takes up cellular cholesterol, and shrinks when HDL cholesterol ester (CE) is transfered to low density lipoprotein (LDL) and very low density lipoprotein (VLDL) particles. The functional ability of HDL (to remove cellular cholesterol) has drawn considerable attention. The fractional esterification rate of cholesterol in HDL (FER(HDL)) has been established as a functional assay of HDL, and reflects the size of HDL particles. We investigated the clinical significance of FER(HDL) and its relationship to the quantity of HDL. FER(HDL) values were inversely correlated with levels of HDL-C and large lipoprotein containing apo A-I (LpA-I). The association between FER(HDL) and CHD changed with serum HDL-C levels: increased FER(HDL) values significantly increased the risk of CHD when serum HDL-C levels were low, while there was no such relationship when HDL-C levels were high. We concluded that the combination of HDL-C levels and FER(HDL) is a stronger indicator of CHD than either the HDL-C level (quantitative measure of HDL) or FER(HDL) (functional measure of HDL) alone.
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Affiliation(s)
- B Zhang
- Department of Cardiology, Fukuoka University School of Medicine, Japan
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45
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Affiliation(s)
- P P Toth
- Sterling Rock Falls Clinic, Southern Illinois University School of Medicine, USA
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46
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Chen MF, Wang TD, Yeh HT, Hsu HC, Lee YT. Gemfibrozil treatment potentiates oxidative resistance of high-density lipoprotein in hypertriglyceridemic patients. Eur J Clin Invest 2001; 31:707-13. [PMID: 11473572 DOI: 10.1046/j.1365-2362.2001.00868.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Studies suggest that both oxidized low and high density lipoprotein (LDL and HDL) play a role in the pathogenesis of atherosclerosis. Gemfibrozil is widely used and is reported to increase cholesterol of LDL and HDL in hypertriglyceridemic patients. The aim of this study was to investigate the effect of gemfibrozil treatment on the oxidative status of lipoprotein particles in Fredrickson phenotype IV hypertriglyceridemic patients. METHODS Twenty-two patients, aged 38-64 years, with fasting plasma triglyceride concentrations between 2.90 and 8.97 mmol L(-1), were recruited and were given gemfibrozil 300 mg three times daily for 12 weeks. Venous blood samples were collected before gemfibrozil treatment, after 4, 8, or 12 weeks of treatment, and 4 weeks after termination of treatment, and used to analyse the plasma lipid profile, isolate lipoproteins, and analyse the chemical composition and in vitro oxidation of lipoprotein particles. RESULTS Gemfibrozil treatment resulted in a decrease in plasma total triglyceride levels and the triglyceride content of all lipoproteins. Plasma total cholesterol levels were decreased as a result of a decrease in very low density lipoprotein (VLDL) cholesterol levels. A slight increase in LDL cholesterol levels was observed, whereas the thiobarbituric acid-reactive substances (TBARS) of LDL were decreased and the lag and peak time of LDL to oxidation were unchanged and maximal diene production was decreased. Plasma HDL cholesterol levels, the surface-to-core ratio of HDL particles, and the resistance of HDL to oxidation were increased. CONCLUSION The decreased TBARS and diene production of LDL, increased HDL cholesterol levels, and increased resistance of HDL to oxidation may, in part, explain why gemfibrozil treatment was found to be generally beneficial in terms of protection against coronary heart disease.
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Affiliation(s)
- M F Chen
- Department of Internal Medicine (Cardiology), National Taiwan University Medical Center, Taipei, Taiwan
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47
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Dubé MP, Sprecher D, Henry WK, Aberg JA, Torriani FJ, Hodis HN, Schouten J, Levin J, Myers G, Zackin R, Nevin T, Currier JS. Preliminary guidelines for the evaluation and management of dyslipidemia in adults infected with human immunodeficiency virus and receiving antiretroviral therapy: Recommendations of the Adult AIDS Clinical Trial Group Cardiovascular Disease Focus Group. Clin Infect Dis 2000; 31:1216-24. [PMID: 11073755 DOI: 10.1086/317429] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2000] [Revised: 07/25/2000] [Indexed: 11/03/2022] Open
Abstract
Dyslipidemia is a prevalent condition that affects patients infected with human immunodeficiency virus (HIV) who are receiving antiretroviral therapy. These preliminary recommendations summarize the current understanding in this area and propose guidelines for management. Existing guidelines for the management of dyslipidemia in the general population formed the general basis for our recommendations. Data on the prevalence and treatment of dyslipidemia of HIV-infected patients, implications of treatment-related dyslipidemia in other chronically ill populations, and pharmacokinetic profiles for the available hypolipidemic agents in non-HIV populations were considered. Although the implications of dyslipidemia in this population are not fully known, the frequency, type, and magnitude of lipid alterations in HIV-infected people are expected to result in increased cardiovascular morbidity. We propose that these patients undergo evaluation and treatment on the basis of existing guidelines for dyslipidemia, with the caveat that avoidance of interactions with antiretroviral agents is paramount.
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Affiliation(s)
- M P Dubé
- Indiana University, Indianapolis, IN 46202, USA.
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48
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Ferguson EE. Preventing, stopping, or reversing coronary artery disease--triglyceride-rich lipoproteins and associated lipoprotein and metabolic abnormalities: the need for recognition and treatment. Dis Mon 2000; 46:421-503. [PMID: 10943222 DOI: 10.1016/s0011-5029(00)90011-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A substantial number of treated patients with or at high risk for coronary artery disease continue to have fatal and nonfatal coronary artery events in spite of significant reduction of elevated levels of low-density lipoprotein cholesterol. Other lipoprotein abnormalities besides an elevated level of low-density lipoprotein cholesterol contribute to risk of coronary artery disease and coronary artery events, and the predominant abnormalities that appear to explain much of this continued risk are an elevated serum triglyceride level and a low level of high-density lipoprotein cholesterol. Most patients with coronary artery disease have a mixed dyslipidemia with hypertriglyceridemia, which is associated and metabolically intertwined with other atherogenic risk factors, including the presence of triglyceride-rich lipoprotein remnants, low levels of high-density lipoprotein cholesterol, small, dense, low-density lipoprotein particles, postprandial hyperlipidemia, and a prothrombotic state. Aggressive treatment of these patients needs to focus on these other lipoprotein abnormalities as much as on low-density lipoprotein cholesterol. Combination drug therapy will usually be required. Reliable assessment of risk of coronary artery disease from lipoprotein measurements and response to therapy requires inclusion of all atherogenic lipoproteins in laboratory measurements and treatment protocols. At present this may be best accomplished by use of non-high-density lipoprotein cholesterol (total cholesterol minus high-density lipoprotein cholesterol) calculated from standard laboratory lipoprotein values. Ultimately, a more comprehensive assessment of coronary artery disease risk and appropriate therapy may include measurement of lipoprotein subclass distribution including determination of low-density lipoprotein particle concentration and sizes of the various lipoprotein particles.
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Affiliation(s)
- E E Ferguson
- Department of Medicine, University of Wisconsin Hospital and Clinics, Madison
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Winkler K, Schaefer JR, Klima B, Nuber C, Friedrich I, Köster W, Gierens H, Scharnagl H, Soufi M, Wieland H, März W. HDL steady state levels are not affected, but HDL apoA-I turnover is enhanced by Lifibrol in patients with hypercholesterolemia and mixed hyperlipidemia. Atherosclerosis 2000; 150:113-20. [PMID: 10781641 DOI: 10.1016/s0021-9150(99)00351-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Lifibrol (4-(4'-tert-butylphenyl)-1-(4'carboxyphenoxy)-2-butanol) is a new hypocholesterolemic drug effectively reducing total cholesterol, LDL cholesterol, and apolipoprotein (apo) B in experimental animals and in humans. In contrast to fibrates and HMG-CoA reductase inhibitors the cholesterol and triglyceride lowering effect of Lifibrol is not accompanied by increases in HDL cholesterol and apoA-I levels. We examined the impact of Lifibrol on the metabolism of HDL apoA-I in patients with hyperlipoproteinemia, using endogenous labeling with stable isotopes. Kinetic studies were performed in five male hypercholesterolemic individuals (type IIa), before and on treatment with 450 mg of Lifibrol daily for 4 weeks and in five male individuals suffering from mixed hyperlipidemia (type IIb), before and on therapy, for 12 weeks. Lifibrol reduced total cholesterol by 14% (P=0.02) and LDL cholesterol by 16% (P=0. 014) in all patients, and decreased triglycerides by 34% in type IIb patients. During Lifibrol therapy, HDL cholesterol and ApoA-I concentrations did not change. Tracer kinetics revealed that the fractional catabolic rate (FCR) of HDL apoA-I increased by 22% (P=0. 013). This increase in the apoA-I FCR was accompanied by a 23% increase in HDL apoA-I production rate (P=0.006). We conclude that Lifibrol, although not changing HDL steady state concentrations, enhances the turnover of apoA-I containing HDL particles.
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Affiliation(s)
- K Winkler
- Department of Medicine, Division of Clinical Chemistry, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany.
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Shiomi M, Ito T, Fujioka T, Tsujita Y. Age-associated decrease in plasma cholesterol and changes in cholesterol metabolism in homozygous Watanabe heritable hyperlipidemic rabbits. Metabolism 2000; 49:552-6. [PMID: 10778885 DOI: 10.1016/s0026-0495(00)80025-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We examined the cholesterol metabolism of homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits, an animal model deficient in low-density lipoprotein (LDL) receptors, to clarify the mechanism of the age-associated decrease of plasma total cholesterol, one of the properties of WHHL rabbits. The rabbits were examined at several ages: after weaning at 3 months, at sexual maturation at 6 months, at 12 months, and at 24 months, equivalent to about 35 years of age in humans. Plasma total cholesterol, triglyceride, and phospholipid levels decreased with aging by about 45%. These reductions were mainly dependent on a decrease in the LDL fraction. In the liver microsomal fraction, although there were no age-related changes in the cholesterol concentration and cholesterol 7alpha-hydroxylase (C7H) activity, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity increased and acyl-coenzyme A:cholesterol acyltransferase (ACAT) activity decreased with aging. The lipolytic activity varied with aging. The secretion rate of very-low-density lipoprotein (VLDL) cholesterol as determined by injection of Triton WR-1339 decreased significantly with aging, while the catabolic rate of VLDL cholesterol was about 2-fold higher in the oldest group versus the young groups. From these results, we conclude that the age-associated decrease in plasma cholesterol in WHHL rabbits is related not only to a decrease in the secretion rate of VLDL cholesterol but also to an increase in the catabolic rate.
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Affiliation(s)
- M Shiomi
- Institute for Experimental Animals, Kobe University School of Medicine, Japan
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