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Windler E, Beil FU, Berthold HK, Gouni-Berthold I, Kassner U, Klose G, Lorkowski S, März W, Parhofer KG, Plat J, Silbernagel G, Steinhagen-Thiessen E, Weingärtner O, Zyriax BC, Lütjohann D. Phytosterols and Cardiovascular Risk Evaluated against the Background of Phytosterolemia Cases-A German Expert Panel Statement. Nutrients 2023; 15:nu15040828. [PMID: 36839186 PMCID: PMC9963617 DOI: 10.3390/nu15040828] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/08/2023] Open
Abstract
Phytosterols (PSs) have been proposed as dietary means to lower plasma LDL-C. However, concerns are raised that PSs may exert atherogenic effects, which would offset this benefit. Phytosterolemia was thought to mimic increased plasma PSs observed after the consumption of PS-enriched foods. This expert statement examines the possibility of specific atherogenicity of PSs based on sterol metabolism, experimental, animal, and human data. Observational studies show no evidence that plasma PS concentrations would be associated with an increased risk of atherosclerosis or cardiovascular (CV) events. Since variants of the ABCG5/8 transporter affect the absorption of cholesterol and non-cholesterol sterols, Mendelian randomization studies examining the effects of ABCG5/8 polymorphisms cannot support or refute the potential atherogenic effects of PSs due to pleiotropy. In homozygous patients with phytosterolemia, total PS concentrations are ~4000% higher than under physiological conditions. The prevalence of atherosclerosis in these individuals is variable and may mainly relate to concomitant elevated LDL-C. Consuming PS-enriched foods increases PS concentrations by ~35%. Hence, PSs, on a molar basis, would need to have 20-40 times higher atherogenicity than cholesterol to offset their cholesterol reduction benefit. Based on their LDL-C lowering and absence of adverse safety signals, PSs offer a dietary approach to cholesterol management. However, their clinical benefits have not been established in long-term CV endpoint studies.
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Affiliation(s)
- Eberhard Windler
- Preventive Medicine, University Heart Center, University Hospital Hamburg-Eppendorf, Hamburg-Eppendorf, Martinistr. 52-Bldg. N26, 20246 Hamburg, Germany
| | - Frank-Ulrich Beil
- Ambulanzzentrum, Universitätsklinikum Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Heiner K. Berthold
- Department of Internal Medicine and Geriatrics, Bethel Clinic, 33611 Bielefeld, Germany
| | - Ioanna Gouni-Berthold
- Center for Endocrinology, Diabetes and Preventive Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Ursula Kassner
- Lipid Clinic at the Interdisciplinary Metabolism Center, Charite-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Gerald Klose
- Praxen Dres. T. Beckenbauer & S. Maierhof, Am Markt 11, 28195 Bremen und Dres. I. van de Loo & K. Spieker, Gerold Janssen Straße 2 A, 28359 Bremen, Germany
| | - Stefan Lorkowski
- Institute of Nutritional Science and Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD), Halle-Jena-Leipzig, Friedrich Schiller University Jena, Dornburger Str. 25, 07743 Jena, Germany
| | - Winfried März
- SYNLAB Akademie für Ärztliche Fortbildung, SYNLAB Holding Deutschland GmbH, P5,7, 68161 Mannheim, Germany
- Medical Clinic V, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8010 Graz, Austria
- Correspondence:
| | - Klaus G. Parhofer
- Medizinische Klinik IV, Klinikum der Universität München, Grosshadern, Marchioninistr. 15, 81377 München, Germany
| | - Jogchum Plat
- Department of Nutrition and Movement Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, 6211 LK Maastricht, The Netherlands
| | - Günter Silbernagel
- Division of Vascular Medicine, Department of Internal Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Elisabeth Steinhagen-Thiessen
- Arbeitsbereich Lipidstoffwechsel der Medizinischen Klinik für Endokrinologie und Stoffwechselmedizin, Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Oliver Weingärtner
- Klinik für Innere Medizin I, Universitätskliniken Jena, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
| | - Birgit-Christiane Zyriax
- Midwifery Science—Health Care Research and Prevention, Research Group, Preventive Medicine and Nutrition, Institute for Health Services Research in Dermatology and Nursing (IVDP), University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Dieter Lütjohann
- Institute of Clinical Chemistry and Clinical Pharmacology, University Clinics Bonn, 53127 Bonn, Germany
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Kwek E, Zhu H, Ding H, He Z, Hao W, Liu J, Ma KY, Chen ZY. Peony seed oil decreases plasma cholesterol and favorably modulates gut microbiota in hypercholesterolemic hamsters. Eur J Nutr 2022; 61:2341-2356. [PMID: 35107625 DOI: 10.1007/s00394-021-02785-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 12/13/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE Peony (Paeonia spp.) seed oil (PSO) contains a high amount of α-linolenic acid. The effects of PSO on hypercholesterolemia and gut microbiota remains unclear. The present study was to investigate effects of PSO supplementation on cholesterol metabolism and modulation of the gut microbiota. METHODS Male Golden Syrian hamsters (n = 40) were randomly divided into five groups (n = 8, each) fed one of the following diets namely low-cholesterol diet (LCD); high cholesterol diet (HCD); HCD with PSO substituting 50% lard (LPSO), PSO substituting 100% lard (HPSO) and HCD with addition of 0.5% cholestyramine (PCD), respectively, for 6 weeks. RESULTS PSO supplementation dose-dependently reduced plasma total cholesterol (TC) by 9-14%, non-high-density lipoprotein cholesterol (non-HDL-C) by 7-18% and triacylglycerols (TG) by 14-34% (p < 0.05). In addition, feeding PSO diets reduced the formation of plaque lesions by 49-61% and hepatic lipids by 9-19% compared with feeding HCD diet (p < 0.01). PSO also altered relative genus abundance of unclassified_f__Coriobacteriaceae, unclassified_f__Erysipelotrichaceae, Peptococcus, unclassified_f__Ruminococcaceae, norank_o__Mollicutes_RF9 and Christensenellaceae_R-7_group. CONCLUSIONS It was concluded that PSO was effective in reducing plasma cholesterol and hepatic lipids and favorably modulating gut microbiota associated with cholesterol metabolism.
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Affiliation(s)
- Erika Kwek
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Hanyue Zhu
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
- School of Food Science and Engineering/South China Food Safety Research Center, Foshan University, Foshan, Guangdong, China
| | - Huafang Ding
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Zouyan He
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
- School of Public Health, Guangxi Medical University, Nanning, 530021, China
| | - Wangjun Hao
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Jianhui Liu
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
- College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, 210023, China
| | - Ka Ying Ma
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Zhen-Yu Chen
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
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3
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Zhang Z, Lu Y, Qi J, Wu W. An update on oral drug delivery via intestinal lymphatic transport. Acta Pharm Sin B 2021; 11:2449-2468. [PMID: 34522594 PMCID: PMC8424224 DOI: 10.1016/j.apsb.2020.12.022] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/14/2020] [Accepted: 12/07/2020] [Indexed: 12/17/2022] Open
Abstract
Orally administered drug entities have to survive the harsh gastrointestinal environment, penetrate the enteric epithelia and circumvent hepatic metabolism before reaching the systemic circulation. Whereas the gastrointestinal stability can be well maintained by taking proper measures, hepatic metabolism presents as a formidable barrier to drugs suffering from first-pass metabolism. The pharmaceutical academia and industries are seeking alternative pathways for drug transport to circumvent problems associated with the portal pathway. Intestinal lymphatic transport is emerging as a promising pathway to this end. In this review, we intend to provide an updated overview on the rationale, strategies, factors and applications involved in intestinal lymphatic transport. There are mainly two pathways for peroral lymphatic transport-the chylomicron and the microfold cell pathways. The underlying mechanisms are being unraveled gradually and nowadays witness increasing research input and applications.
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Key Words
- ACQ, aggregation-caused quenching
- ASRT, apical sodium-dependent bile acid transporter
- AUC, area under curve
- BCS, biopharmaceutics classification system
- CM, chylomicron
- Chylomicron
- DC, dendritic cell
- DDT, dichlorodiphenyltrichloroethane
- DTX, docetaxel
- Drug absorption
- Drug carriers
- Drug delivery
- FA, fatty acid
- FAE, follicle-associated epithelia
- FRET, Föster resonance energy transfer
- GIT, gastrointestinal tract
- HBsAg, hepatitis B surface antigen
- HIV, human immunodeficiency virus
- LDL, low-density lipoprotein
- LDV, Leu-Asp-Val
- LDVp, LDV peptidomimetic
- Lymphatic transport
- M cell, microfold cells
- MG, monoglyceride
- MPA, mycophenolic acid
- MPS, mononuclear phagocyte system
- Microfold cell
- Nanoparticles
- OA, oleate
- Oral
- PCL, polycaprolactone
- PEG-PLA, polyethylene glycol-poly(lactic acid)
- PEI, polyethyleneimine
- PLGA, poly(lactic-co-glycolic acid)
- PVA, poly(vinyl alcohol)
- RGD, Arg-Gly-Asp
- RGDp, RGD peptidomimetic
- SEDDS, self-emulsifying drug delivery system
- SLN, solid lipid nanoparticles
- SNEDDS, self-nanoemulsifying drug delivery system
- TEM, transmission electron microscopy
- TG, triglyceride
- TPGS, D-α-tocopherol polyethylene glycol 1000 succinate
- TU, testosterone undecanoate
- WGA, wheat germ agglutinin
- YCW, yeast cell wall
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Affiliation(s)
- Zichen Zhang
- Key Laboratory of Smart Drug Delivery of MOE, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Yi Lu
- Key Laboratory of Smart Drug Delivery of MOE, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Jianping Qi
- Key Laboratory of Smart Drug Delivery of MOE, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Wei Wu
- Key Laboratory of Smart Drug Delivery of MOE, School of Pharmacy, Fudan University, Shanghai 201203, China
- Center for Medical Research and Innovation, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai 201399, China
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Williams K, Segard A, Graf GA. Sitosterolemia: Twenty Years of Discovery of the Function of ABCG5ABCG8. Int J Mol Sci 2021; 22:2641. [PMID: 33807969 PMCID: PMC7961684 DOI: 10.3390/ijms22052641] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/19/2021] [Accepted: 02/26/2021] [Indexed: 02/06/2023] Open
Abstract
Sitosterolemia is a lipid disorder characterized by the accumulation of dietary xenosterols in plasma and tissues caused by mutations in either ABCG5 or ABCG8. ABCG5 ABCG8 encodes a pair of ABC half transporters that form a heterodimer (G5G8), which then traffics to the surface of hepatocytes and enterocytes and promotes the secretion of cholesterol and xenosterols into the bile and the intestinal lumen. We review the literature from the initial description of the disease, the discovery of its genetic basis, current therapy, and what has been learned from animal, cellular, and molecular investigations of the transporter in the twenty years since its discovery. The genomic era has revealed that there are far more carriers of loss of function mutations and likely pathogenic variants of ABCG5 ABCG8 than previously thought. The impact of these variants on G5G8 structure and activity are largely unknown. We propose a classification system for ABCG5 ABCG8 mutants based on previously published systems for diseases caused by defects in ABC transporters. This system establishes a framework for the comprehensive analysis of disease-associated variants and their impact on G5G8 structure-function.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily G, Member 5/genetics
- ATP Binding Cassette Transporter, Subfamily G, Member 5/history
- ATP Binding Cassette Transporter, Subfamily G, Member 5/metabolism
- ATP Binding Cassette Transporter, Subfamily G, Member 8/genetics
- ATP Binding Cassette Transporter, Subfamily G, Member 8/history
- ATP Binding Cassette Transporter, Subfamily G, Member 8/metabolism
- Animals
- Cholesterol/metabolism
- Enterocytes/metabolism
- Enterocytes/pathology
- Hepatocytes/metabolism
- Hepatocytes/pathology
- History, 21st Century
- Humans
- Hypercholesterolemia/genetics
- Hypercholesterolemia/history
- Hypercholesterolemia/metabolism
- Hypercholesterolemia/pathology
- Intestinal Diseases/genetics
- Intestinal Diseases/history
- Intestinal Diseases/metabolism
- Intestinal Diseases/pathology
- Lipid Metabolism, Inborn Errors/genetics
- Lipid Metabolism, Inborn Errors/history
- Lipid Metabolism, Inborn Errors/metabolism
- Lipid Metabolism, Inborn Errors/pathology
- Lipoproteins/genetics
- Lipoproteins/history
- Lipoproteins/metabolism
- Mutation
- Phytosterols/adverse effects
- Phytosterols/genetics
- Phytosterols/history
- Phytosterols/metabolism
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Affiliation(s)
- Kori Williams
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA; (K.W.); (A.S.)
| | - Allison Segard
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA; (K.W.); (A.S.)
| | - Gregory A. Graf
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA; (K.W.); (A.S.)
- Saha Cardiovascular Research Center, Lexington, KY 40536, USA
- Barnstable Brown Diabetes and Obesity Center, Lexington, KY 40536, USA
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5
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ABCG5/G8: a structural view to pathophysiology of the hepatobiliary cholesterol secretion. Biochem Soc Trans 2020; 47:1259-1268. [PMID: 31654053 PMCID: PMC6824678 DOI: 10.1042/bst20190130] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/26/2019] [Accepted: 09/30/2019] [Indexed: 12/17/2022]
Abstract
The ABCG5/G8 heterodimer is the primary neutral sterol transporter in hepatobiliary and transintestinal cholesterol excretion. Inactivating mutations on either the ABCG5 or ABCG8 subunit cause Sitosterolemia, a rare genetic disorder. In 2016, a crystal structure of human ABCG5/G8 in an apo state showed the first structural information on ATP-binding cassette (ABC) sterol transporters and revealed several structural features that were observed for the first time. Over the past decade, several missense variants of ABCG5/G8 have been associated with non-Sitosterolemia lipid phenotypes. In this review, we summarize recent pathophysiological and structural findings of ABCG5/G8, interpret the structure-function relationship in disease-causing variants and describe the available evidence that allows us to build a mechanistic view of ABCG5/G8-mediated sterol transport.
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6
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Mechanisms and regulation of cholesterol homeostasis. Nat Rev Mol Cell Biol 2019; 21:225-245. [DOI: 10.1038/s41580-019-0190-7] [Citation(s) in RCA: 450] [Impact Index Per Article: 90.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2019] [Indexed: 12/14/2022]
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7
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Karadagi A, Johansson H, Zemack H, Salipalli S, Mörk LM, Kannisto K, Jorns C, Gramignoli R, Strom S, Stokkeland K, Ericzon BG, Jonigk D, Janciauskiene S, Nowak G, Ellis ECS. Exogenous alpha 1-antitrypsin down-regulates SERPINA1 expression. PLoS One 2017; 12:e0177279. [PMID: 28486562 PMCID: PMC5423693 DOI: 10.1371/journal.pone.0177279] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/01/2017] [Indexed: 11/19/2022] Open
Abstract
The main goal of the therapy with purified human plasma alpha1-antitrypsin (A1AT) is to increase A1AT levels and to prevent lungs from elastolytic activity in patients with PiZZ (Glu342Lys) A1AT deficiency-related emphysema. Potential hepatic gains of this therapy are unknown. Herein, we investigated the effect of A1AT therapy on SERPINA1 (gene encoding A1AT) expression. The expression of SERPINA1 was determined in A1AT or A1AT plus Oncostatin M (OSM) treated primary human hepatocytes isolated from liver tissues from A1AT deficient patients and control liver tissues. In addition, SERPINA1 mRNA was assessed in lung tissues from PiZZ emphysema patients with and without A1AT therapy, and in adherent human peripheral blood mononuclear cells (PBMC) isolated from healthy PiMM donors. In a dose-dependent manner purified A1AT lowered SERPINA1 expression in hepatocytes. This latter effect was more prominent in hepatocytes stimulated with OSM. Although it did not reach statistical significance (P = 0.0539)-analysis of lung tissues showed lower SERPINA1 expression in PiZZ emphysema patients receiving augmentation therapy relative to those without therapy. Finally, exogenously added purified A1AT (1mg/ml) reduced SERPINA1 expression in naïve as well as in lipopolysaccharide (LPS)-stimulated human adherent PBMCs. Exogenous A1AT protein reduces its own endogenous expression. Hence, augmentation with native M-A1AT protein and a parallel reduction in expression of dysfunctional mutant Z-A1AT may be beneficial for PiZZ liver, and this motivates further studies.
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Affiliation(s)
- Ahmad Karadagi
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Helene Johansson
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Helen Zemack
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Sandeep Salipalli
- Department of Respiratory Medicine, Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany
| | - Lisa-Mari Mörk
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Kristina Kannisto
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Carl Jorns
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Roberto Gramignoli
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Stephen Strom
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Knut Stokkeland
- Department of Medicine, Visby Hospital, Visby, Sweden
- Department of Medicine, Gastroenterology and Hepatology Unit, Karolinska Institute, Stockholm, Sweden
| | - Bo-Göran Ericzon
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Danny Jonigk
- Institute of Pathology, Hannover Medical School, Hannover, Germany
| | - Sabina Janciauskiene
- Department of Respiratory Medicine, Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany
| | - Greg Nowak
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Ewa C S Ellis
- Division of Transplantation Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
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Soayfane Z, Tercé F, Cantiello M, Robenek H, Nauze M, Bézirard V, Allart S, Payré B, Capilla F, Cartier C, Peres C, Al Saati T, Théodorou V, Nelson DW, Yen CLE, Collet X, Coméra C. Exposure to dietary lipid leads to rapid production of cytosolic lipid droplets near the brush border membrane. Nutr Metab (Lond) 2016; 13:48. [PMID: 27478484 PMCID: PMC4965885 DOI: 10.1186/s12986-016-0107-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 07/21/2016] [Indexed: 12/17/2022] Open
Abstract
Background Intestinal absorption of dietary lipids involves their hydrolysis in the lumen of proximal intestine as well as uptake, intracellular transport and re-assembly of hydrolyzed lipids in enterocytes, leading to the formation and secretion of the lipoproteins chylomicrons and HDL. In this study, we examined the potential involvement of cytosolic lipid droplets (CLD) whose function in the process of lipid absorption is poorly understood. Methods Intestinal lipid absorption was studied in mouse after gavage. Three populations of CLD were purified by density ultracentrifugations, as well as the brush border membranes, which were analyzed by western-blots. Immunofluorescent localization of membranes transporters or metabolic enzymes, as well as kinetics of CLD production, were also studied in intestine or Caco-2 cells. Results We isolated three populations of CLD (ranging from 15 to 1000 nm) which showed differential expression of the major lipid transporters scavenger receptor BI (SR-BI), cluster of differentiation 36 (CD-36), Niemann Pick C-like 1 (NPC1L1), and the ATP-binding cassette transporters ABCG5/G8 but also caveolin 2 and fatty acid binding proteins. The enzyme monoacylglycerol acyltransferase 2 (MGAT2) was identified in the brush border membrane (BBM) in addition to the endoplasmic reticulum, suggesting local synthesis of triglycerides and CLD at both places. Conclusions We show a very fast production of CLD by enterocytes associated with a transfer of apical constituents as lipid transporters. Our findings suggest that following their uptake by enterocytes, lipids can be partially metabolized at the BBM and packaged into CLD for their transportation to the ER. Electronic supplementary material The online version of this article (doi:10.1186/s12986-016-0107-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zeina Soayfane
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France
| | - François Tercé
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France
| | - Michela Cantiello
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France
| | - Horst Robenek
- Leibniz-Institut für Arterioskleroseforschung, Universität Münster, Münster, Germany
| | - Michel Nauze
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France
| | - Valérie Bézirard
- UMR 1331 Toxalim, INRA, Université de Toulouse, ENVT, INP-Purpan, 180 chemin de Tournefeuille, BP 93173, 31027 Toulouse, cedex 3, France
| | - Sophie Allart
- INSERM UMR 1043 (INSERM/UPS/CNRS/USC Inra), CHU Purpan, Toulouse, France
| | - Bruno Payré
- CMEAB, Faculté de Médecine Rangueil, Toulouse, France
| | - Florence Capilla
- INSERM/UPS - US006/CREFRE, Service d'Histopathologie, CHU Purpan, Toulouse, France
| | - Christel Cartier
- UMR 1331 Toxalim, INRA, Université de Toulouse, ENVT, INP-Purpan, 180 chemin de Tournefeuille, BP 93173, 31027 Toulouse, cedex 3, France
| | - Christine Peres
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France
| | - Talal Al Saati
- INSERM/UPS - US006/CREFRE, Service d'Histopathologie, CHU Purpan, Toulouse, France
| | - Vassilia Théodorou
- UMR 1331 Toxalim, INRA, Université de Toulouse, ENVT, INP-Purpan, 180 chemin de Tournefeuille, BP 93173, 31027 Toulouse, cedex 3, France
| | - David W Nelson
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI USA
| | - Chi-Liang Eric Yen
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI USA
| | - Xavier Collet
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France
| | - Christine Coméra
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, UMR 1048, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, F-31000 France.,UMR 1331 Toxalim, INRA, Université de Toulouse, ENVT, INP-Purpan, 180 chemin de Tournefeuille, BP 93173, 31027 Toulouse, cedex 3, France
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Uwiera RR, Mangat R, Kelly S, Uwiera TC, Proctor SD. Long-Term Catheterization of the Intestinal Lymph Trunk and Collection of Lymph in Neonatal Pigs. J Vis Exp 2016. [PMID: 27023826 DOI: 10.3791/53457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Catheterization of the intestinal lymph trunk in neonatal pigs is a technique allowing for the long-term collection of large quantities of intestinal (central) efferent lymph. Importantly, the collection of central lymph from the intestine enables researchers to study both the mechanisms and lipid constitutes associated with lipid metabolism, intestinal inflammation and cancer metastasis, as well as cells involved in immune function and immunosurveillance. A ventral mid-line surgical approach permits excellent surgical exposure to the cranial abdomen and relatively easy access to the intestinal lymph trunk vessel that lies near the pancreas and the right ventral segment of the portal vein underneath the visceral aspect of the right liver lobe. The vessel is meticulously dissected and released from the surrounding fascia and then dilated with sutures allowing for insertion and subsequent securing of the catheter into the vessel. The catheter is exteriorized and approximately 1 L/24 hr of lymph is collected over a 7 day period. While this technique enables the collection of large quantities of central lymph over an extended period of time, the success depends on careful surgical dissection, tissue handling and close attention to proper surgical technique. This is particularly important with surgeries in young animals as the lymph vessels can easily tear, potentially leading to surgical and experimental failure. The video demonstrates an excellent surgical technique for the collection of intestinal lymph.
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Affiliation(s)
- Richard R Uwiera
- Department of Agricultural, Food and Nutritional Science, University of Alberta;
| | - Rabban Mangat
- Department of Agricultural, Food and Nutritional Science, University of Alberta
| | - Sandra Kelly
- Department of Agricultural, Food and Nutritional Science, University of Alberta
| | | | - Spencer D Proctor
- Department of Agricultural, Food and Nutritional Science, University of Alberta
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10
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ABCG5/G8 deficiency in mice reduces dietary triacylglycerol and cholesterol transport into the lymph. Lipids 2015; 50:371-9. [PMID: 25676339 DOI: 10.1007/s11745-015-3995-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 02/01/2015] [Indexed: 10/24/2022]
Abstract
The adenosine triphosphate-binding cassette (ABC) transporter G5/G8 is critical in protecting the body from accumulating dietary plant sterols. Expressed in the liver and small intestine, it transports plant sterols into the biliary and intestinal lumens, thus promoting their excretion. The extent to which G5/G8 regulates cholesterol absorption remains unclear. G5/G8 is also implicated in reducing the absorption of dietary triacylglycerols (TAG) by unknown mechanisms. We hypothesized that G5/G8 suppresses the production of chylomicrons, and its deficiency would enhance the absorption of both dietary TAG and cholesterol. The aim of this study was to investigate the effects of G5/G8 deficiency on lipid uptake and secretion into the lymph under steady-state conditions. Surprisingly, compared with wild-type mice (WT) (n = 9), G5/G8 KO (n = 13) lymph fistula mice given a continuous intraduodenal infusion of [3H]-TAG and [14C]-cholesterol showed a significant (P < 0.05) reduction in lymphatic transport of both [(3)H]-TAG and [(14)C]-cholesterol, concomitant with a significant (P < 0.05) increase of [(3)H]-TAG and [(14)C]-cholesterol accumulated in the intestinal lumen. There was no difference in the total amount of radiolabeled lipids retained in the intestinal mucosa between the two groups. G5/G8 KO mice given a bolus of TAG showed reduced intestinal TAG secretion compared with WT, suggesting an independent role for G5/G8 in facilitating intestinal TAG transport. Our data demonstrate that G5/G8 deficiency reduces the uptake and secretion of both dietary TAG and cholesterol by the intestine, suggesting a novel role for the sterol transporter in the formation and secretion of chylomicrons.
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11
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Wang X, Huang W, Lei L, Liu Y, Ma KY, Li YM, Wang L, Huang Y, Chen ZY. Blockage of hydroxyl group partially abolishes the cholesterol-lowering activity of β-sitosterol. J Funct Foods 2015. [DOI: 10.1016/j.jff.2014.11.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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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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Sodhi SS, Ghosh M, Song KD, Sharma N, Kim JH, Kim NE, Lee SJ, Kang CW, Oh SJ, Jeong DK. An approach to identify SNPs in the gene encoding acetyl-CoA acetyltransferase-2 (ACAT-2) and their proposed role in metabolic processes in pig. PLoS One 2014; 9:e102432. [PMID: 25050817 PMCID: PMC4106792 DOI: 10.1371/journal.pone.0102432] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 06/17/2014] [Indexed: 12/01/2022] Open
Abstract
The novel liver protein acetyl-CoA acetyltransferase-2 (ACAT2) is involved in the beta-oxidation and lipid metabolism. Its comprehensive relative expression, in silico non-synonymous single nucleotide polymorphism (nsSNP) analysis, as well as its annotation in terms of metabolic process with another protein from the same family, namely, acetyl-CoA acyltransferase-2 (ACAA2) was performed in Sus scrofa. This investigation was conducted to understand the most important nsSNPs of ACAT2 in terms of their effects on metabolic activities and protein conformation. The two most deleterious mutations at residues 122 (I to V) and 281 (R to H) were found in ACAT2. Validation of expression of genes in the laboratory also supported the idea of differential expression of ACAT2 and ACAA2 conceived through the in silico analysis. Analysis of the relative expression of ACAT2 and ACAA2 in the liver tissue of Jeju native pig showed that the former expressed significantly higher (P<0.05). Overall, the computational prediction supported by wet laboratory analysis suggests that ACAT2 might contribute more to metabolic processes than ACAA2 in swine. Further associations of SNPs in ACAT2 with production traits might guide efforts to improve growth performance in Jeju native pigs.
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Affiliation(s)
- Simrinder Singh Sodhi
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Mrinmoy Ghosh
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Ki Duk Song
- The Animal Genomics and Breeding Center, Hankyong National University, Anseong-si, Gyeonggi-do, South Korea
| | - Neelesh Sharma
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Jeong Hyun Kim
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Nam Eun Kim
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Sung Jin Lee
- Department of Animal Biotechnology, College of Animal Bioscience and Technology, Kangwon National University, Chuncheon, South Korea
| | - Chul Woong Kang
- Department of Mechanical and System Engineering, College of Engineering, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Sung Jong Oh
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
| | - Dong Kee Jeong
- Department of Animal Biotechnology, Faculty of Biotechnology, Jeju National University, Jeju-si, Jeju-do, South Korea
- Sustainable Agriculture Research Institute (SARI), Jeju National University, Jeju-si, Jeju-do, South Korea
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14
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Escolà-Gil JC, Quesada H, Julve J, Martín-Campos JM, Cedó L, Blanco-Vaca F. Sitosterolemia: Diagnosis, Investigation, and Management. Curr Atheroscler Rep 2014; 16:424. [DOI: 10.1007/s11883-014-0424-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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15
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Chuang JC, Valasek MA, Lopez AM, Posey KS, Repa JJ, Turley SD. Sustained and selective suppression of intestinal cholesterol synthesis by Ro 48-8071, an inhibitor of 2,3-oxidosqualene:lanosterol cyclase, in the BALB/c mouse. Biochem Pharmacol 2014; 88:351-63. [PMID: 24486573 DOI: 10.1016/j.bcp.2014.01.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 01/17/2014] [Accepted: 01/21/2014] [Indexed: 01/11/2023]
Abstract
The small intestine plays a fundamentally important role in regulating whole body cholesterol balance and plasma lipoprotein composition. This is articulated through the interplay of a constellation of genes that ultimately determines the net amount of chylomicron cholesterol delivered to the liver. Major advances in our insights into regulation of the cholesterol absorption pathway have been made using genetically manipulated mouse models and agents such as ezetimibe. One unresolved question is how a sustained pharmacological inhibition of intestinal cholesterol synthesis in vivo may affect cholesterol handling by the absorptive cells. Here we show that the lanosterol cyclase inhibitor, Ro 48-8071, when fed to BALB/c mice in a chow diet (20 mg/day/kg body weight), leads to a rapid and sustained inhibition (>50%) of cholesterol synthesis in the whole small intestine. Sterol synthesis was also reduced in the large intestine and stomach. In contrast, hepatic cholesterol synthesis, while markedly suppressed initially, rebounded to higher than baseline rates within 7 days. Whole body cholesterol synthesis, fractional cholesterol absorption, and fecal neutral and acidic sterol excretion were not consistently changed with Ro 48-8071 treatment. There were no discernible effects of this agent on intestinal histology as determined by H&E staining and the level of Ki67, an index of proliferation. The mRNA expression for multiple genes involved in intestinal cholesterol regulation including NPC1L1 was mostly unchanged although there was a marked rise in the mRNA level for the PXR target genes CYP3A11 and CES2A.
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Affiliation(s)
- Jen-Chieh Chuang
- Departments of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States.
| | - Mark A Valasek
- Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States.
| | - Adam M Lopez
- Departments of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States.
| | - Kenneth S Posey
- Departments of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States.
| | - Joyce J Repa
- Departments of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States; Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States.
| | - Stephen D Turley
- Departments of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, United States.
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16
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Othman RA, Myrie SB, Jones PJH. Non-cholesterol sterols and cholesterol metabolism in sitosterolemia. Atherosclerosis 2013; 231:291-9. [PMID: 24267242 DOI: 10.1016/j.atherosclerosis.2013.09.038] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 09/05/2013] [Accepted: 09/30/2013] [Indexed: 12/14/2022]
Abstract
Sitosterolemia (STSL) is a rare autosomal recessive disease, manifested by extremely elevated plant sterols (PS) in plasma and tissue, leading to xanthoma and premature atherosclerotic disease. Therapeutic approaches include limiting PS intake, interrupting enterohepatic circulation of bile acid using bile acid binding resins such as cholestyramine, and/or ileal bypass, and inhibiting intestinal sterol absorption by ezetimibe (EZE). The objective of this review is to evaluate sterol metabolism in STSL and the impact of the currently available treatments on sterol trafficking in this disease. The role of PS in initiation of xanthomas and premature atherosclerosis is also discussed. Blocking sterols absorption with EZE has revolutionized STSL patient treatment as it reduces circulating levels of non-cholesterol sterols in STSL. However, none of the available treatments including EZE have normalized plasma PS concentrations. Future studies are needed to: (i) explore where cholesterol and non-cholesterol sterols accumulate, (ii) assess to what extent these sterols in tissues can be mobilized after blocking their absorption, and (iii) define the factors governing sterol flux.
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Affiliation(s)
- Rgia A Othman
- Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Richardson Centre for Functional Foods and Nutraceuticals, University of Manitoba, Winnipeg, Manitoba, Canada
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17
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Quantitative analysis of the effect of triglyceride alkyl-chain length on the partitioning of highly lipophilic compounds to the mesenteric lymph in intestinal cells. Arch Pharm Res 2013; 37:937-46. [PMID: 24081442 DOI: 10.1007/s12272-013-0249-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 09/20/2013] [Indexed: 12/26/2022]
Abstract
The purpose of this study was to quantitatively clarify the effect of alky-chain length of a triglyceride in an emulsion on the partitioning of highly lipophilic compounds into the lymph fluid after their oral administration. Highly lipophilic anthraquinone derivatives were orally administered in emulsions to rats. Emulsions composed of long-, medium-, and short-chain triglycerides (LCT, MCT, and SCT emulsions, respectively) were used. The concentrations of the compounds in plasma and lymph fluid were periodically determined and their partitioning to the lymph was calculated using a mathematical model. Intestinal absorption of all compounds was enhanced and the plasma concentrations of the compounds were found to be in the following order: LCT emulsion > MCT emulsion > SCT emulsion. The amounts of each compound recovered in the lymph were not in agreement with their lipophilicity. Quantitative analysis revealed that the partitioning of the compounds to the lymph may be determined by the solubility of the compound in the triglyceride in the form of an emulsion and the amount of triglyceride transferred to the lymph fluid. These results suggest a possibility that the amount of a compound absorbed via the lymph route after oral administration can be quantitatively controlled by the formulations.
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18
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Sontag TJ, Chellan B, Getz GS, Reardon CA. Differing rates of cholesterol absorption among inbred mouse strains yield differing levels of HDL-cholesterol. J Lipid Res 2013; 54:2515-24. [PMID: 23812556 DOI: 10.1194/jlr.m040055] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Inbred strains of mice with differing susceptibilities to atherosclerosis possess widely varying plasma HDL levels. Cholesterol absorption and lipoprotein formation were compared between atherosclerosis-susceptible, low-HDL C57BL6/J mice and atherosclerosis-resistant, high-HDL FVBN/J mice. [(3)H]cholesterol and triglyceride appeared in the plasma of FVB mice gavaged with cholesterol in olive oil at a much higher rate than in C57 mice. The plasma cholesterol was found almost entirely as HDL-cholesterol in both strains. Inhibition of lipoprotein catabolism with Tyloxapol revealed that the difference in the rate of [(3)H]cholesterol appearance in the plasma was due entirely to a greater rate of chylomicron secretion from the intestine of the FVB mice. Lipid absorption into the 2nd quarter of the small intestine is greater in the FVB mice and indicates that this region may contain the factors that give rise to the differences in absorption observed between the two mouse strains. Additionally, ad libitum feeding prior to cholesterol gavage accentuates the absorption rate differences compared with fasting. The resultant remodeling of the increased levels of chylomicron in the plasma may contribute to increased plasma HDL. Intestinal gene expression analysis reveals several genes that may play a role in these differences, including microsomal triglyceride transfer protein and ABCG8.
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Affiliation(s)
- Timothy J Sontag
- Department of Pathology, University of Chicago, Chicago, IL, USA.
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