1
|
André R, Pacheco R, Alves AC, Santos HM, Bourbon M, Serralheiro ML. The Hypocholesterolemic Potential of the Edible Algae Fucus vesiculosus: Proteomic and Quantitative PCR Analysis. Foods 2023; 12:2758. [PMID: 37509850 PMCID: PMC10379601 DOI: 10.3390/foods12142758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 06/29/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
A brown seaweed consumed worldwide, Fucus vesiculosus, has been used to prevent atherosclerosis and hypercholesterolemia, among other uses. However, the mechanisms of action that lead to these effects are not yet fully understood. This work aims to study the in vitro effect of an aqueous extract of F. vesiculosus, previously characterized as rich in phlorotannins and peptides, on the expression of different proteins involved in the synthesis and transport of cholesterol. A proteomic analysis, Western blot, and qRT-PCR analysis were performed to identify protein changes in HepG2 cells exposed to 0.25 mg/mL of the F. vesiculosus extract for 24 h. The proteomic results demonstrated that, in liver cells, the extract decreases the expression of four proteins involved in the cholesterol biosynthesis process (CYP51A1, DHCR24, HMGCS1 and HSD17B7). Additionally, a 12.76% and 18.40% decrease in the expression of two important transporters proteins of cholesterol, NPC1L1 and ABCG5, respectively, was also observed, as well as a 30% decrease in NPC1L1 mRNA levels in the cells exposed to the extract compared to control cells. Our study reveals some of the mechanisms underlying the actions of bioactive compounds from F. vesiculosus that may explain its previously reported hypocholesterolemic effect, future prospecting its use as a functional food.
Collapse
Affiliation(s)
- Rebeca André
- BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Rita Pacheco
- Department of Chemical Engineering, ISEL-Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Emídio Navarro, 1, 1959-007 Lisboa, Portugal
- Centro de Química Estrutural, Institute of Molecular Sciences, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Ana Catarina Alves
- BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
| | - Hugo M Santos
- LAQV@REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
- PROTEOMASS Scientific Society, Madan Park, Rúa dos Inventores, 2825-182 Caparica, Portugal
| | - Mafalda Bourbon
- BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Unidade de I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
| | - Maria Luísa Serralheiro
- BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Department of Chemistry and Biochemistry, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, C8 Bldg, 1749-016 Lisboa, Portugal
| |
Collapse
|
2
|
Sun F, Yang X, Ma C, Zhang S, Yu L, Lu H, Yin G, Liang P, Feng Y, Zhang F. The Effects of Diosgenin on Hypolipidemia and Its Underlying Mechanism: A Review. Diabetes Metab Syndr Obes 2021; 14:4015-4030. [PMID: 34552341 PMCID: PMC8450287 DOI: 10.2147/dmso.s326054] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 09/01/2021] [Indexed: 12/15/2022] Open
Abstract
Hyperlipidemia is a disorder of lipid metabolism, which is a major cause of coronary heart disease. Although there has been considerable progress in hyperlipidemia treatment, morbidity and risk associated with the condition continue to rise. The first-line treatment for hyperlipidemia, statins, has multiple side effects; therefore, development of safe and effective drugs from natural products to prevent and treat hyperlipidemia is necessary. Diosgenin is primarily derived from fenugreek (Trigonella foenum graecum) seeds, and is also abundant in medicinal herbs such as Dioscorea rhizome, Dioscorea septemloba, and Rhizoma polygonati, is a well-known steroidal sapogenin and the active ingredient in many drugs to treat cardiovascular conditions. There is abundant evidence that diosgenin has potential for application in correcting lipid metabolism disorders. In this review, we evaluated the latest evidence related to diosgenin and hyperlipidemia from clinical and animal studies. Additionally, we elaborate the pharmacological mechanism underlying the activity of diosgenin in treating hyperlipidemia in detail, including its role in inhibition of intestinal absorption of lipids, regulation of cholesterol transport, promotion of cholesterol conversion into bile acid and its excretion, inhibition of endogenous lipid biosynthesis, antioxidation and lipoprotein lipase activity, and regulation of transcription factors related to lipid metabolism. This review provides a deep exploration of the pharmacological mechanisms involved in diosgenin-hyperlipidemia interactions and suggests potential routes for the development of novel drug therapies for hyperlipidemia.
Collapse
Affiliation(s)
- Fengcui Sun
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Xiufen Yang
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Chaoqun Ma
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Shizhao Zhang
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Lu Yu
- Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, People's Republic of China
| | - Haifei Lu
- Hubei University of Traditional Chinese Medicine, Wuhan, 430065, People's Republic of China
| | - Guoliang Yin
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Pengpeng Liang
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Yanan Feng
- Shandong University of Traditional Chinese Medicine, Jinan, 250000, People’s Republic of China
| | - Fengxia Zhang
- Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250011, People’s Republic of China
- Correspondence: Fengxia Zhang Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250011, People’s Republic of ChinaTel +8653168616011 Email
| |
Collapse
|
3
|
Toyoda Y, Takada T, Yamanashi Y, Suzuki H. Pathophysiological importance of bile cholesterol reabsorption: hepatic NPC1L1-exacerbated steatosis and decreasing VLDL-TG secretion in mice fed a high-fat diet. Lipids Health Dis 2019; 18:234. [PMID: 31883528 PMCID: PMC6935138 DOI: 10.1186/s12944-019-1179-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/23/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide, although its pathogenesis remains to be elucidated. A recent study revealed that hepatic Niemann-Pick C1-Like 1 (NPC1L1), a cholesterol re-absorber from bile to the liver expressed on the bile canalicular membrane, is an exacerbation factor of NAFLD. Indeed, transgenic mice with hepatic expression of human NPC1L1 under a liver-specific promoter (L1-Tg mice) developed steatosis with a high-fat diet (HFD) containing cholesterol within a few weeks. However, the mechanism underlying diet-induced hepatic NPC1L1-mediated lipid accumulation is poorly defined. METHODS To achieve a deeper understanding of steatosis development in L1-Tg mice, the biochemical features of hepatic NPC1L1-mediated steatosis were investigated. Hemizygous L1-Tg mice and wild-type littermate controls fed a HFD or control-fat diet were used. At the indicated time points, the livers were evaluated for cholesterol and triglyceride (TG) contents as well as mRNA levels of hepatic genes involved in the maintenance of lipid homeostasis. The hepatic ability to secrete very low-density lipoprotein (VLDL)-TG was also investigated. RESULTS Unlike the livers of wild-type mice that have little expression of hepatic Npc1l1, the livers of L1-Tg mice displayed time-dependent changes that indicated steatosis formation. In steatosis, there were three different stages of development: mild accumulation of hepatic cholesterol and TG (early stage), acceleration of hepatic TG accumulation (middle stage), and further accumulation of hepatic cholesterol (late stage). In the early stage, between WT and L1-Tg mice fed a HFD for 2 weeks, there were no significant differences in the hepatic expression of Pparα, Acox1, Fat/Cd36, Srebf1, and Srebf2; however, the hepatic ability to secrete VLDL-TG decreased in L1-Tg mice (P < 0.05). Furthermore, this decrease was completely prevented by administration of ezetimibe, an NPC1L1-selective inhibitor. CONCLUSION Hepatic NPC1L1 exacerbates diet-induced steatosis, which was accompanied by decreased hepatic ability of VLDL-TG secretion. The obtained results provide a deeper understanding of L1-Tg mice as a promising NAFLD animal model that is able to re-absorb biliary-secreted cholesterol similar to humans. Furthermore, this work supports further studies of the pathophysiological impact of re-absorbed biliary cholesterol on the regulation of hepatic lipid homeostasis.
Collapse
Affiliation(s)
- Yu Toyoda
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Tappei Takada
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
| | - Yoshihide Yamanashi
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Hiroshi Suzuki
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| |
Collapse
|
4
|
Poongavanam V, Kongsted J, Wüstner D. Computational Modeling Explains the Multi Sterol Ligand Specificity of the N-Terminal Domain of Niemann-Pick C1-Like 1 Protein. ACS OMEGA 2019; 4:20894-20904. [PMID: 31867479 PMCID: PMC6921270 DOI: 10.1021/acsomega.9b01668] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 10/18/2019] [Indexed: 06/10/2023]
Abstract
Niemann-Pick C1 like 1 (NPC1L1) is a sterol transporter expressed in the apical membrane of enterocytes and hepatocytes. NPC1L1 resembles the lysosomal NPC1 protein including an N-terminal domain (NTD), which binds a variety of sterols. The molecular mechanisms underlying this multiligand specificity of the NTD of NPC1L1 (NPC1L1-NTD) are not known. On the basis of the crystal structure of NPC1L1-NTD, we have investigated the structural details of protein-sterol interactions using molecular mechanics Poisson Boltzmann surface area calculations here. We found a good agreement between experimental and calculated binding affinities with similar ranking of various sterol ligands. We defined hydrogen bonding of sterol ligands via the 3'-β-hydroxy group inside the binding pose as instrumental in stabilizing the interaction. A leucine residue (LEU213) at the mouth of the binding pocket transiently opens to allow for the access of sterol into the binding pose. Our calculations also predict that NPC1L1-NTD binds polyene sterols, such as dehydroergosterol or cholestatrienol with high affinity, which validates their use in future experiments as close intrinsically fluorescent cholesterol analogs. A free energy decomposition and computational mutation analysis revealed that the binding of various sterols to NPC1L1-NTD depends critically on specific amino acid residues within the binding pocket. Some of these residues were previously detected as being relevant for intestinal cholesterol absorption. We show that clinically known mutations in the NPC1L1-NTD associated with lowered risk of coronary heart disease result in strongly reduced binding energies, providing a molecular explanation for the clinical phenotype.
Collapse
Affiliation(s)
- Vasanthanathan Poongavanam
- Department of Physics, Chemistry and Pharmacy and Department of Biochemistry and
Molecular Biology, University of Southern
Denmark, DK-5230 Odense M, Denmark
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy and Department of Biochemistry and
Molecular Biology, University of Southern
Denmark, DK-5230 Odense M, Denmark
| | - Daniel Wüstner
- Department of Physics, Chemistry and Pharmacy and Department of Biochemistry and
Molecular Biology, University of Southern
Denmark, DK-5230 Odense M, Denmark
| |
Collapse
|
5
|
Ahmed O, Littmann K, Gustafsson U, Pramfalk C, Öörni K, Larsson L, Minniti ME, Sahlin S, Camejo G, Parini P, Eriksson M. Ezetimibe in Combination With Simvastatin Reduces Remnant Cholesterol Without Affecting Biliary Lipid Concentrations in Gallstone Patients. J Am Heart Assoc 2019; 7:e009876. [PMID: 30561264 PMCID: PMC6405603 DOI: 10.1161/jaha.118.009876] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background In randomized trials (SHARP [Study of Heart and Renal Protection], IMPROVE‐IT [Improved Reduction of Outcomes: Vytorin Efficacy International Trial]), combination of statin and ezetimibe resulted in additional reduction of cardiovascular events. The reduction was greater in patients with type 2 diabetes mellitus (T2DM), where elevated remnant cholesterol and high cardiovascular disease risk is characteristic. To evaluate possible causes behind these results, 40 patients eligible for cholecystectomy, randomized to simvastatin, ezetimibe, combined treatment (simvastatin+ezetimibe), or placebo treatment during 4 weeks before surgery, were studied. Methods and Results Fasting blood samples were taken before treatment start and at the end (just before surgery). Bile samples and liver biopsies were collected during surgery. Hepatic gene expression levels were assessed with qPCR. Lipoprotein, apolipoprotein levels, and content of cholesterol, cholesteryl ester, and triglycerides were measured after lipoprotein fractionation. Lipoprotein subclasses were analyzed by nuclear magnetic resonance. Apolipoprotein affinity for human arterial proteoglycans (PG) was measured. Biomarkers of cholesterol biosynthesis and intestinal absorption and bile lipid composition were analyzed using mass spectrometry. Combined treatment caused a statistically significant decrease in plasma remnant particles and apolipoprotein B (ApoB)/lipoprotein content of cholesterol, cholesteryl esters, and triglycerides. All treatments reduced ApoB‐lipoprotein PG binding. Simvastatin and combined treatment modified the composition of lipoproteins. Changes in biomarkers of cholesterol synthesis and absorption and bile acid synthesis were as expected. No adverse events were found. Conclusions Combined treatment caused atheroprotective changes on ApoB‐lipoproteins, remnant particles, bile components, and in ApoB‐lipoprotein affinity for arterial PG. These effects might explain the decrease of cardiovascular events seen in the SHARP and IMPROVE‐IT trials. Clinical Trial Registration URL: www.clinicaltrialsregister.eu. Unique identifier: 2006‐004839‐30).
Collapse
Affiliation(s)
- Osman Ahmed
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden.,2 Department of Biochemistry Faculty of Medicine Khartoum University Khartoum Sudan
| | - Karin Littmann
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden.,3 Function Area Clinical Chemistry Karolinska University Laboratory Function Karolinska University Hospital Stockholm Sweden
| | - Ulf Gustafsson
- 5 Department of Surgery Karolinska Institutet at Danderyd Hospital Stockholm Sweden
| | - Camilla Pramfalk
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden
| | | | - Lilian Larsson
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden
| | - Mirko E Minniti
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden
| | - Staffan Sahlin
- 5 Department of Surgery Karolinska Institutet at Danderyd Hospital Stockholm Sweden
| | - German Camejo
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden
| | - Paolo Parini
- 1 Division of Clinical Chemistry Department of Laboratory Medicine Karolinska Institutet Stockholm Sweden.,4 Patient Area Endocrinology and Nephrology, Inflammation and Infection Theme Karolinska University Hospital Stockholm Sweden.,7 Metabolism Unit Department of Medicine Karolinska Institutet at Karolinska University Hospital Huddinge Stockholm Sweden
| | - Mats Eriksson
- 4 Patient Area Endocrinology and Nephrology, Inflammation and Infection Theme Karolinska University Hospital Stockholm Sweden.,7 Metabolism Unit Department of Medicine Karolinska Institutet at Karolinska University Hospital Huddinge Stockholm Sweden
| |
Collapse
|
6
|
Wang Y, Yang P, Zhang B, Ding Y, Lei S, Hou Y, Guan X, Li Q. Hepatic NPC1L1 overexpression attenuates alcoholic autophagy in mice. Mol Med Rep 2019; 20:3224-3232. [PMID: 31432115 PMCID: PMC6755247 DOI: 10.3892/mmr.2019.10549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/27/2019] [Indexed: 01/25/2023] Open
Abstract
Alcohol consumption causes liver steatosis in humans. Metabolic disorders of lipids are one of the factors that cause liver steatosis in hepatocytes. Hepatic Niemann‑Pick C1‑like 1 (NPC1L1) regulates lipid homeostasis in mammals. The relationship between NPC1L1 and autophagy in those with a history of alcohol abuse is unclear. The present study aimed to investigate the function of NPC1L1 in the activation of hepatic autophagy in a mouse model with a human (h)NPC1L1 transgene under alcohol feeding conditions. The mice expressing hNPC1L1 (Ad‑L1) or controls (Ad‑null) were created by retro‑orbital adenovirus injection. The Ad‑L1 and Ad‑null mice were fed with alcohol or a non‑alcoholic diet to mimic chronic alcohol consumption in humans. Hepatic autophagy was demonstrated in isolated primary hepatocytes by monitoring autophagic vacuoles under fluorescence microscopy, and by western blotting for autophagic makers. Isolated hepatocytes from the livers of Ad‑L1 mice were treated with different doses of ezetimibe to study the restoration of autophagy. Chronic alcohol feeding caused liver injury and steatosis, shown by significantly higher levels of plasma alanine transaminase and aspartate transaminase activity, and by hematoxylin and eosin staining in Ad‑L1 and Ad‑null mice. Compared to Ad‑null control mice, the microtubule‑associated proteins 1A/1B light chain 3 (LC3) particles in the isolated hepatocytes of Ad‑L1 mice were decreased, both under alcohol and non‑alcoholic feeding. The ratio of LC3II/LC3I was significantly decreased, and the level of p62/sequestosome‑1 protein was significantly increased in Ad‑L1 mice compared with Ad‑null mice after alcohol feeding. Levels of LC3II protein were statistically increased in hepatocytes isolated from Ad‑L1 mice with ezetimibe treatment. The increase in LC3II expression was dose dependent. Within the tested range, it reached its highest level at 40 µM. The livers of Ad‑L1 mice represent a more human‑like state for the study of hepatic autophagy. Hepatic expression of human NPC1L1 resulted in an inhibition of autophagy; it may contribute to alcoholic fatty liver disease in humans.
Collapse
Affiliation(s)
- Youlin Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
| | - Pan Yang
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Bo Zhang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
| | - Yao Ding
- Department of Oncology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, P.R. China
| | - Shun Lei
- Department of Oncology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, P.R. China
| | - Yuning Hou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Xiaoqing Guan
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Qingwang Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China
| |
Collapse
|
7
|
Yamamoto H, Yamanashi Y, Takada T, Mu S, Tanaka Y, Komine T, Suzuki H. Hepatic Expression of Niemann-Pick C1-Like 1, a Cholesterol Reabsorber from Bile, Exacerbates Western Diet-Induced Atherosclerosis in LDL Receptor Mutant Mice. Mol Pharmacol 2019; 96:47-55. [PMID: 31064810 DOI: 10.1124/mol.119.115840] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/02/2019] [Indexed: 11/22/2022] Open
Abstract
Westernization of dietary habits increases lipid intake and is responsible for increased numbers of patients with atherosclerotic diseases. Niemann-Pick C1-Like 1 (NPC1L1)-a cholesterol importer-plays a crucial role in dietary cholesterol absorption in the intestine and is closely associated with several lipid-related diseases, including atherosclerosis. NPC1L1 is highly expressed in the liver and intestine in humans, whereas NPC1L1 expression is low in the rodent liver. Due to species differences in the tissue distribution of NPC1L1, there are limited studies on the pathophysiological role of hepatic NPC1L1, a cholesterol reabsorber from bile. In the present study, to explore whether hepatic NPC1L1 is involved in the development/progression of atherosclerosis, we compared four kinds of atherosclerosis mouse models with different expression levels of NPC1L1 in the intestinal and liver tissues in a genetic background of dysfunctional low-density lipoprotein receptor mutation. Western diet (WD)-induced hyperlipidemia and atherosclerotic plaque formation were more severe in mice expressing NPC1L1 in both the liver and intestine (plasma cholesterol, 839.5 mg/dl; plaque area, 29.5% of total aorta), compared with mice expressing NPC1L1 only in the intestine (plasma cholesterol, 573.1 mg/dl; plaque area, 13.3% of total aorta). Such hepatic NPC1L1-mediated promotion of hyperlipidemia and atherosclerosis was not observed in mice not expressing intestinal NPC1L1 and mice treated with ezetimibe, an NPC1L1 inhibitor used clinically for dyslipidemia. These results suggested that hepatic NPC1L1 promotes WD-induced dyslipidemia and atherosclerosis in concert with intestinal NPC1L1. Our findings provide novel insights into the pathophysiological importance of hepatic NPC1L1 in development/progression of atherosclerosis. SIGNIFICANCE STATEMENT: Niemann-Pick C1-Like 1 (NPC1L1) protein, a cholesterol importer and a molecular target of ezetimibe clinically used for dyslipidemia, is highly expressed not only in the intestine, but also in the liver in humans, although the pathophysiological importance of hepatic NPC1L1 in atherosclerotic diseases remained unclear. By using novel mouse models to separately analyze the effects of hepatic and intestinal NPC1L1 on the development/progression of atherosclerosis, we first demonstrated that hepatic NPC1L1 accelerates Western diet-induced atherosclerotic plaque formation in an intestinal NPC1L1-dependent and an ezetimibe-sensitive manner.
Collapse
Affiliation(s)
- Hideaki Yamamoto
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yoshihide Yamanashi
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tappei Takada
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Shuang Mu
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yusuke Tanaka
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Toko Komine
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Suzuki
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
8
|
Wang Y, Tang W, Yang P, Shin H, Li Q. Hepatic NPC1L1 promotes hyperlipidemia in LDL receptor deficient mice. Biochem Biophys Res Commun 2018; 499:626-633. [DOI: 10.1016/j.bbrc.2018.03.200] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 03/27/2018] [Indexed: 10/17/2022]
|
9
|
Gil-Ramírez A, Morales D, Soler-Rivas C. Molecular actions of hypocholesterolaemic compounds from edible mushrooms. Food Funct 2018; 9:53-69. [DOI: 10.1039/c7fo00835j] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Edible mushrooms contain bioactive compounds able to modulate the expression of genes related to absorption, biosynthesis and transport of cholesterol and regulation of its homeostasis.
Collapse
Affiliation(s)
- Alicia Gil-Ramírez
- Department of Production and Characterization of Novel Foods
- CIAL – Research Institute in Food Science (UAM+CSIC)
- C/Nicolas Cabrera 9
- Campus de Cantoblanco
- Universidad Autonoma de Madrid
| | - Diego Morales
- Department of Production and Characterization of Novel Foods
- CIAL – Research Institute in Food Science (UAM+CSIC)
- C/Nicolas Cabrera 9
- Campus de Cantoblanco
- Universidad Autonoma de Madrid
| | - Cristina Soler-Rivas
- Department of Production and Characterization of Novel Foods
- CIAL – Research Institute in Food Science (UAM+CSIC)
- C/Nicolas Cabrera 9
- Campus de Cantoblanco
- Universidad Autonoma de Madrid
| |
Collapse
|
10
|
Chen Z, Lei YL, Wang WP, Lei YY, Liu YH, Hei J, Hu J, Sui H. Effects of Saponin from Trigonella Foenum-Graecum Seeds on Dyslipidemia. IRANIAN JOURNAL OF MEDICAL SCIENCES 2017; 42:577-585. [PMID: 29184266 PMCID: PMC5684379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Saponins identified from fenugreek (Trigonella foenum-graecum) seeds are reported effective on dyslipidemia. However, the definite mechanism is still not elucidated systematically. In this study, we evaluate the effects of saponin extract on cholesterol absorption, metabolism, synthesis, and reverse cholesterol transport in vivo. METHODS Saponin extract was prepared according to a craft established in our previous study. After the establishment of dyslipidemia model, 40 male Sprague-Dawley rats were divided into five groups, namely the control group (normal diet plus normal saline), HFD group (high fat diet plus normal saline), Lipitor group (high fat diet plus Lipitor (2 mg/kg)), and L, M, and H-saponin groups (high fat diet plus saponin in dosages of 6, 12, and 24 mg/kg, respectively). Rats were sacrificed at the end of the 9th week after treatment. Biochemical characteristics of rats were tested, histopathological sections of liver tissue were observed, and the protein and mRNA expression of related factors of cholesterol in the intestine and liver were determined. One-way ANOVA test (SPSS software version 11.5, Chicago, IL, USA) was used to determine statistically significant differences between the HFD and other groups. RESULTS In saponin groups, the serum lipid, bile acid efflux, anti-peroxide activities, and lipid area of liver tissue improved. Cholesterol 7alpha-hydroxylase and scavenger receptor class B type I elevated in the liver. 3-hydroxy-3-methylglutaryl coenzyme A reductase levels were suppressed in both the serum and liver. However, significant cholesterol efflux was not found and Niemann-Pick C1-Like 1 levels elevated in the intestine. CONCLUSION The mechanisms of saponin in Fenugreek effect on ameliorating dyslipidemia are probably related to accelerated cholesterol metabolism, inhibited cholesterol synthesis, and facilitated reverse cholesterol transport, but not cholesterol absorption.
Collapse
Affiliation(s)
- Zhi Chen
- Faculty of Medicine, Shimane University, Shimane, Japan,School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China
| | - Yan-Li Lei
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China
| | - Wen-Ping Wang
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China,Ningxia Engineering and Technology Research Center, Modernization of Hui Medicine, Yinchuan Ningxia, China,Key Lab of Hui Ethnic Medicine Modernization, Ministry of Education, Yinchuan Ningxia, China
| | - Ya-Ya Lei
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China,General Hospital of Ningxia Medical University, Yinchuan Ningxia, China
| | - Yan-Hua Liu
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China,Ningxia Engineering and Technology Research Center, Modernization of Hui Medicine, Yinchuan Ningxia, China,Key Lab of Hui Ethnic Medicine Modernization, Ministry of Education, Yinchuan Ningxia, China
| | - Jing Hei
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China,General Hospital of Ningxia Medical University, Yinchuan Ningxia, China
| | - Jin Hu
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China,General Hospital of Ningxia Medical University, Yinchuan Ningxia, China
| | - Hong Sui
- School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia, China,Ningxia Engineering and Technology Research Center, Modernization of Hui Medicine, Yinchuan Ningxia, China,Key Lab of Hui Ethnic Medicine Modernization, Ministry of Education, Yinchuan Ningxia, China,Correspondence: Hong Sui, PhD; School of Pharmacy, Ningxia Medical University, Yinchuan Ningxia 750001, China Tel: +86 139 95113086 Fax: +86 951 6880693
| |
Collapse
|
11
|
Lin J, Shao WQ, Chen QZ, Zhu WW, Lu L, Jia HL, Chen JH. Osteopontin deficiency protects mice from cholesterol gallstone formation by reducing expression of intestinal NPC1L1. Mol Med Rep 2017. [PMID: 28627641 PMCID: PMC5561929 DOI: 10.3892/mmr.2017.6774] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Homeostasis of cholesterol is regulated by absorption in the intestine and synthesis in the liver. The authors previously demonstrated that OPN (osteopontin) exhibits the ability to alter hepatic cholesterol metabolism, thus affecting cholesterol gallstone formation in mice. The present study investigated the role of OPN in cholesterol gallstone formation, focusing on its effect on intestinal absorption of cholesterol. OPN gene knockout (OPN−/−) mice and wild-type mice were respectively fed with a chow or lithogenic diet (LD) for 8 weeks. Following an 8-week LD period, the incidence of gallstone, bile composition, level of serum and fecal lipids and the expression of intestinal associated genes were analyzed. OPN−/− mice were protected from gallstone formation induced by 8 weeks' LD-feeding. This protective effect from OPN deficiency was associated with alterations in bile composition, including a reduced concentration of biliary cholesterol. Additionally, plasma cholesterol level was decreased in LD-fed OPN−/− mice. The alterations primarily resulted from the decreased expression of intestinal Niemann-Pick C1-like (NPC1 L) 1, which is important in the intestinal absorption of cholesterol. The present study demonstrated that OPN deficiency reduced intestinal absorption of cholesterol by suppressing the expression of NPC1L1, thus protecting mice from cholesterol gallstone formation.
Collapse
Affiliation(s)
- Jing Lin
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Wei-Qing Shao
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Qing-Zhi Chen
- Shanghai Huayu Private Middle School, Shanghai 200231, P.R. China
| | - Wen-Wei Zhu
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Lu Lu
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Hu-Liang Jia
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Jin-Hong Chen
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| |
Collapse
|
12
|
Wu J, Cui W, Cai Q, Fei J, Zhang SD, Han TQ, Hu H, Jiang ZY. The NPC1L1 Polymorphism 1679C>G Is Associated with Gallstone Disease in Chinese Patients. PLoS One 2016; 11:e0147562. [PMID: 26800364 PMCID: PMC4723254 DOI: 10.1371/journal.pone.0147562] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/04/2016] [Indexed: 01/07/2023] Open
Abstract
Niemann Pick Type C1 Like 1 (NPC1L1) protein plays a key role in intestinal and hepatic cholesterol metabolism in humans. Genetic variation in NPC1L1 has been widely studied in recent years. We analyzed NPC1L1 single nucleotide polymorphisms in Chinese gallstone disease patients to investigate their association with gallstone disease. NPC1L1 mRNA expression was also measured in liver biopsies from patients with cholesterol gallstone disease and compared between genotypes. The G allele of the g1679C>G (rs2072183) polymorphism was significantly more prevalent in patients with gallstones compared with gallstone-free subjects. Moreover, patients carrying the G allele had lower hepatic NPC1L1 mRNA expression and higher biliary cholesterol (molar percentages) and cholesterol saturation index. Our study suggests that the G allele of the NPC1L1 polymorphism g1679C>G may be a positive marker of gallstone formation risk.
Collapse
Affiliation(s)
- Jian Wu
- Department of Hepatobiliary and Pancreatic Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
- Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wei Cui
- Department of Surgery, Yijishan Hospital, Wannan Medical College, Jiangsu Province, China
| | - Qu Cai
- Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jian Fei
- Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Sheng-Dao Zhang
- Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Tian-Quan Han
- Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hai Hu
- Department of Hepatobiliary and Pancreatic Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
- * E-mail: (ZYJ); (HH)
| | - Zhao-Yan Jiang
- Department of Hepatobiliary and Pancreatic Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
- * E-mail: (ZYJ); (HH)
| |
Collapse
|
13
|
Fuller S, Stephens JM. Diosgenin, 4-hydroxyisoleucine, and fiber from fenugreek: mechanisms of actions and potential effects on metabolic syndrome. Adv Nutr 2015; 6:189-97. [PMID: 25770257 PMCID: PMC4352177 DOI: 10.3945/an.114.007807] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Metabolic syndrome and its complications continue to rise in prevalence and show no signs of abating in the immediate future. Therefore, the search for effective treatments is a high priority in biomedical research. Products derived from botanicals have a time-honored history of use in the treatment of metabolic diseases including type 2 diabetes. Trigonella foenum-graecum, commonly known as fenugreek, is an annual herbaceous plant that has been a staple of traditional herbal medicine in many cultures. Although fenugreek has been studied in both clinical and basic research settings, questions remain about its efficacy and biologic mechanisms of action. Diosgenin, 4-hydroxyisoleucine, and the fiber component of the plant are the most intensively studied bioactive constituents present in fenugreek. These compounds have been demonstrated to exert beneficial effects on several physiologic markers including glucose tolerance, inflammation, insulin action, liver function, blood lipids, and cardiovascular health. Although insights into the molecular mechanisms underlying the favorable effects of fenugreek have been gained, we still do not have definitive evidence establishing its role as a therapeutic agent in metabolic disease. This review aims to summarize the currently available evidence on the physiologic effects of the 3 best-characterized bioactive compounds of fenugreek, with particular emphasis on biologic mechanisms of action relevant in the context of metabolic syndrome.
Collapse
Affiliation(s)
- Scott Fuller
- Pennington Biomedical Research Center, Baton Rouge, LA; and
| | - Jacqueline M Stephens
- Pennington Biomedical Research Center, Baton Rouge, LA; and Department of Biological Sciences, Louisiana State University, Baton Rouge, LA
| |
Collapse
|
14
|
Fomiroid A, a novel compound from the mushroom Fomitopsis nigra, inhibits NPC1L1-mediated cholesterol uptake via a mode of action distinct from that of ezetimibe. PLoS One 2014; 9:e116162. [PMID: 25551765 PMCID: PMC4281142 DOI: 10.1371/journal.pone.0116162] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 12/03/2014] [Indexed: 12/11/2022] Open
Abstract
Hypercholesterolemia is one of the key risk factors for coronary heart disease, a major cause of death in developed countries. Suppression of NPC1L1-mediated dietary and biliary cholesterol absorption is predicted to be one of the most effective ways to reduce the risk of hypercholesterolemia. In a screen for natural products that inhibit ezetimibe glucuronide binding to NPC1L1, we found a novel compound, fomiroid A, in extracts of the mushroom Fomitopsis nigra. Fomiroid A is a lanosterone derivative with molecular formula C30H48O3. Fomiroid A inhibited ezetimibe glucuronide binding to NPC1L1, and dose-dependently prevented NPC1L1-mediated cholesterol uptake and formation of esterified cholesterol in NPC1L1-expressing Caco2 cells. Fomiroid A exhibited a pharmacological chaperone activity that corrected trafficking defects of the L1072T/L1168I mutant of NPC1L1. Because ezetimibe does not have such an activity, the binding site and mode of action of fomiroid A are likely to be distinct from those of ezetimibe.
Collapse
|
15
|
Arya N, Kharjul MD, Shishoo CJ, Thakare VN, Jain KS. Some molecular targets for antihyperlipidemic drug research. Eur J Med Chem 2014; 85:535-68. [DOI: 10.1016/j.ejmech.2014.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 08/01/2014] [Accepted: 08/05/2014] [Indexed: 12/17/2022]
|
16
|
Castro-Torres IG, De la O-Arciniega M, Bravo-Duarte GA, Gallegos-Estudillo J, Domínguez-Ortíz MÁ, Martínez-Vázquez M. Intestinal and hepatic Niemann–Pick C1L1 proteins: Future therapeutic targets for cholesterol gallstones disease? Eur J Pharmacol 2014; 728:77-81. [DOI: 10.1016/j.ejphar.2014.01.067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 01/13/2014] [Accepted: 01/24/2014] [Indexed: 02/07/2023]
|
17
|
Renaud HJ, Cui JY, Lu H, Klaassen CD. Effect of diet on expression of genes involved in lipid metabolism, oxidative stress, and inflammation in mouse liver-insights into mechanisms of hepatic steatosis. PLoS One 2014; 9:e88584. [PMID: 24551121 PMCID: PMC3925138 DOI: 10.1371/journal.pone.0088584] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 01/08/2014] [Indexed: 12/11/2022] Open
Abstract
Nutritional intake is a fundamental determinant of health. Many studies have correlated excess caloric intake, as well as a high ratio of n-6:n-3 fatty acids, with detrimental health outcomes, such as the metabolic syndrome. In contrast, low-calorie diets have beneficial health effects. Despite these associations, our understanding of the causal relationship between diet and health remains largely elusive. The present study examined the molecular changes elicited by nine diets with varying fat, sugar, cholesterol, omega-3 fatty acids, omega-6 fatty acids, and calories in C57BL/6 male mice. Microarray analyses were conducted on liver samples from three mice per diet and detected 20,449 genes of which 3,734 were responsive to changes in dietary components. Principal component analysis showed that diet restriction correlated the least with the other diets and also affected more genes than any other diet. Interestingly, Gene Set Enrichment Analysis (GSEA) identified gene sets involved in glutathione metabolism, immune response, fatty acid metabolism, cholesterol metabolism, ABC transporters, and oxidative phosphorylation as being highly responsive to changes in diet composition. On the gene level, this study reveals novel findings such as the induction of the drug efflux pump Abcb1a (p-glycoprotein) by diet restriction and an atherogenic diet, as well as the suppression of the rate limiting step of bile acid synthesis, Cyp7a1, by a high fructose diet. This study provides considerable insight into the molecular changes incurred by a variety of diets and furthers our understanding of the causal relationships between diet and health.
Collapse
Affiliation(s)
- Helen J Renaud
- Department of Internal Medicine, Kansas University Medical Center, Kansas City, Kansas, United States of America
| | - Julia Y Cui
- Department of Internal Medicine, Kansas University Medical Center, Kansas City, Kansas, United States of America
| | - Hong Lu
- Department of Pharmacology, State University of New York, Syracuse, New York, United States of America
| | - Curtis D Klaassen
- Department of Internal Medicine, Kansas University Medical Center, Kansas City, Kansas, United States of America
| |
Collapse
|
18
|
van der Wulp MYM, Verkade HJ, Groen AK. Regulation of cholesterol homeostasis. Mol Cell Endocrinol 2013; 368:1-16. [PMID: 22721653 DOI: 10.1016/j.mce.2012.06.007] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 05/17/2012] [Accepted: 06/11/2012] [Indexed: 12/28/2022]
Abstract
Hypercholesterolemia is an important risk factor for cardiovascular disease. It is caused by a disturbed balance between cholesterol secretion into the blood versus uptake. The pathways involved are regulated via a complex interplay of enzymes, transport proteins, transcription factors and non-coding RNA's. The last two decades insight into underlying mechanisms has increased vastly but there are still a lot of unknowns, particularly regarding intracellular cholesterol transport. After decades of concentration on the liver, in recent years the intestine has come into focus as an important control point in cholesterol homeostasis. This review will discuss current knowledge of cholesterol physiology, with emphasis on cholesterol absorption, cholesterol synthesis and fecal excretion, and new (possible) therapeutic options for hypercholesterolemia.
Collapse
|
19
|
Xie P, Jia L, Ma Y, Ou J, Miao H, Wang N, Guo F, Yazdanyar A, Jiang XC, Yu L. Ezetimibe inhibits hepatic Niemann-Pick C1-Like 1 to facilitate macrophage reverse cholesterol transport in mice. Arterioscler Thromb Vasc Biol 2013; 33:920-5. [PMID: 23471229 DOI: 10.1161/atvbaha.112.301187] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Controversies have arisen from recent mouse studies about the essential role of biliary sterol secretion in reverse cholesterol transport (RCT). The objective of this study was to examine the role of biliary cholesterol secretion in modulating macrophage RCT in Niemann-Pick C1-Like 1 (NPC1L1) liver only (L1(LivOnly)) mice, an animal model that is defective in both biliary sterol secretion and intestinal sterol absorption, and determine whether NPC1L1 inhibitor ezetimibe facilitates macrophage RCT by inhibiting hepatic NPC1L1. APPROACH AND RESULTS L1(LivOnly) mice were generated by crossing NPC1L1 knockout (L1-KO) mice with transgenic mice overexpressing human NPC1L1 specifically in liver. Macrophage-to-feces RCT was assayed in L1-KO and L1(LivOnly) mice injected intraperitoneally with [(3)H]-cholesterol-labeled peritoneal macrophages isolated from C57BL/6 mice. Inhibition of biliary sterol secretion by hepatic overexpression of NPC1L1 substantially reduced transport of [(3)H]-cholesterol from primary peritoneal macrophages to the neutral sterol fraction in bile and feces in L1(LivOnly) mice without affecting tracer excretion in the bile acid fraction. Ezetimibe treatment for 2 weeks completely restored both biliary and fecal excretion of [(3)H]-tracer in the neutral sterol fraction in L1(LivOnly) mice. High-density lipoprotein kinetic studies showed that L1(LivOnly) mice compared with L1-KO mice had a significantly reduced fractional catabolic rate without altered hepatic and intestinal uptake of high-density lipoprotein-cholesterol ether. CONCLUSIONS In mice lacking intestinal cholesterol absorption, macrophage-to-feces RCT depends on efficient biliary sterol secretion, and ezetimibe promotes macrophage RCT by inhibiting hepatic NPC1L1 function.
Collapse
Affiliation(s)
- Ping Xie
- Department of Biochemistry, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Catapano A, Toth PP, Tomassini JE, Tershakovec AM. The efficacy and safety of ezetimibe coadministered with statin therapy in various patient groups. ACTA ACUST UNITED AC 2013. [DOI: 10.2217/clp.12.88] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
21
|
Park Y, Carr TP. Unsaturated fatty acids and phytosterols regulate cholesterol transporter genes in Caco-2 and HepG2 cell lines. Nutr Res 2012; 33:154-61. [PMID: 23399666 DOI: 10.1016/j.nutres.2012.11.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 11/18/2012] [Accepted: 11/20/2012] [Indexed: 12/21/2022]
Abstract
Dietary consumption of phytosterols and certain fatty acids has been shown to reduce cholesterol absorption and plasma cholesterol concentrations. However, it has not been fully elucidated whether phytosterols or fatty acids can alter the expression of cholesterol transporters by functioning as signaling molecules. This study tested the hypothesis that various fatty acids and phytosterols commonly found in the food supply can modulate the expression of transporters including Niemann-Pick C1-like 1, low-density lipoprotein receptor, and scavenger receptor class B type I and 3-hydroxy-3-methylglutaryl-coenzyme A reductase in the intestine and liver. Caco-2 cells were used as models of enterocytes, and HepG2 cells were used as a model of hepatocytes. The cells were treated for 18 hours with 100 μmol/L of a fatty acid, or for 24 hours with 10 μmol/L of 25α-hydroxycholesterol, or 100 μmol/L of cholesterol, sitosterol, and stigmasterol to measure expression of genes involved in cholesterol transport using quantitative real-time polymerase chain reaction. Polyunsaturated fatty acids in Caco-2 cells and sterols in HepG2 cells significantly reduced the messenger RNA expression levels of Niemann-Pick C1-like 1, scavenger receptor class B type I, low-density lipoprotein receptor, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Importantly, sitosterol and stigmasterol reduced the messenger RNA levels of genes to a similar extent as cholesterol. The data support the hypothesis that unsaturated fatty acid and phytosterols can act as signaling molecules and alter the expression of genes involved in cholesterol transport and metabolism.
Collapse
Affiliation(s)
- Youngki Park
- Department of Nutrition and Health Sciences, University of Nebraska, Lincoln, NE 68583-0806, USA
| | | |
Collapse
|
22
|
Abstract
Emerging experimental and human evidence has linked altered hepatic cholesterol homeostasis and free cholesterol (FC) accumulation to the pathogenesis of non-alcoholic steatohepatits (NASH). This review focuses on cellular mechanisms of cholesterol toxicity involved in liver injury and on alterations in cholesterol homeostasis promoting hepatic cholesterol overload in NASH. FC accumulation injures hepatocytes directly, by disrupting mitochondrial and endoplasmic reticulum (ER) membrane integrity, triggering mitochondrial oxidative injury and ER stress, and by promoting generation of toxic oxysterols, and indirectly, by inducing adipose tissue dysfunction. Accumulation of oxidized LDL particles may also activate Kupffer and hepatic stellate cells, promoting liver inflammation and fibrogenesis. Hepatic cholesterol accumulation is driven by a deeply deranged cellular cholesterol homeostasis, characterized by elevated cholesterol synthesis and uptake from circulating lipoproteins and by a reduced cholesterol excretion. Extensive dysregulation of cellular cholesterol homeostasis by nuclear transcription factors sterol regulatory binding protein (SREBP)-2, liver X-receptor (LXR)-α and farnesoid X receptor (FXR) plays a key role in hepatic cholesterol accumulation in NASH. The therapeutic implications and opportunities for normalizing cellular cholesterol homeostasis in these patients are also discussed.
Collapse
|
23
|
Bibliography. Hyperlipidaemia and cardiovascular disease. Current world literature. Curr Opin Lipidol 2012; 23:386-91. [PMID: 22801387 DOI: 10.1097/mol.0b013e32835670af] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
24
|
Lipid-altering efficacy of ezetimibe plus statin and statin monotherapy and identification of factors associated with treatment response: A pooled analysis of over 21,000 subjects from 27 clinical trials. Atherosclerosis 2012; 223:251-61. [DOI: 10.1016/j.atherosclerosis.2012.02.016] [Citation(s) in RCA: 168] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 02/01/2012] [Accepted: 02/08/2012] [Indexed: 12/17/2022]
|
25
|
Portincasa P, Wang DQH. Intestinal absorption, hepatic synthesis, and biliary secretion of cholesterol: where are we for cholesterol gallstone formation? Hepatology 2012; 55:1313-6. [PMID: 22271308 DOI: 10.1002/hep.25604] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/04/2012] [Indexed: 12/28/2022]
|
26
|
Niemann-Pick C1-Like 1 and cholesterol uptake. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:964-72. [PMID: 22480541 DOI: 10.1016/j.bbalip.2012.03.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 03/09/2012] [Accepted: 03/12/2012] [Indexed: 01/27/2023]
Abstract
Niemann-Pick C1-Like 1 (NPC1L1) is a polytopic transmembrane protein responsible for dietary cholesterol and biliary cholesterol absorption. Consistent with its functions, NPC1L1 distributes on the brush border membrane of enterocytes and the canalicular membrane of hepatocytes in humans. As the molecular target of ezetimibe, a hypocholesterolemic drug, its physiological and pathological significance has been recognized and intensively studied for years. Recently, plenty of new findings reveal the molecular mechanism of NPC1L1's role in cholesterol uptake, which may provide new insights on our understanding of cholesterol absorption. In this review, we summarized recent progress in these studies and proposed a working model, hoping to provide new perspectives on the regulation of cholesterol transport and metabolism.
Collapse
|
27
|
Davis HR, Tershakovec AM, Tomassini JE, Musliner T. Intestinal sterol transporters and cholesterol absorption inhibition. Curr Opin Lipidol 2011; 22:467-78. [PMID: 22101558 DOI: 10.1097/mol.0b013e32834c7c28] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Statin therapy is the mainstay of lipid-lowering therapy; however, many patients, particularly those at high risk, do not achieve sufficient LDL-cholesterol (LDL-C) lowering. Thus, there remains an unmet medical need for more effective and well tolerated lipid-lowering agents. Guidelines recommend combining additional lipid-lowering agents with a complementary mode of action for these patients. One approach to complementing statin therapy is combination with inhibitors that block the intestinal absorption of dietary and biliary cholesterol. This review summarizes what is currently known about intestinal sterol transporters and cholesterol absorption inhibitors (CAIs). RECENT FINDINGS The only lipid-lowering agent currently available that specifically targets an intestinal sterol transporter (Niemann-Pick C1-like 1) is the CAI, ezetimibe. It is effective in lowering LDL-C, both when given alone and when combined with a statin. Clinical outcome data with ezetimibe combined with simvastatin have recently become available, and definitive evidence that the incremental LDL-C lowering attributable to the ezetimibe component reduces cardiovascular events beyond simvastatin alone is currently under study. Other novel CAIs have been evaluated based upon the structure and properties of ezetimibe, but none remain in development. SUMMARY Additional lipid-lowering agents are needed to fulfill an unmet medical need for those patients who do not achieve optimal LDL-C goals on statin monotherapy. The inhibition of cholesterol absorption is an important therapeutic strategy to reduce cholesterol levels. Based upon the demonstrated lipid-altering efficacy and safety of ezetimibe, several CAIs have been identified; all to date have been discontinued due to limited efficacy.
Collapse
Affiliation(s)
- Harry R Davis
- Merck Research Laboratories, Merck Sharp & Dohme Corp./Merck & Co., Inc., Whitehouse Station, New Jersey, USA.
| | | | | | | |
Collapse
|