1
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Mo P, Chen H, Jiang X, Hu F, Zhang F, Shan G, Chen W, Li S, Xu G. Effect of hepatic NPC1L1 on cholesterol gallstone disease and its mechanism. Heliyon 2023; 9:e15757. [PMID: 37159680 PMCID: PMC10163659 DOI: 10.1016/j.heliyon.2023.e15757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 05/11/2023] Open
Abstract
Cholesterol gallstone disease (CGD) is associated with bile cholesterol supersaturation. The Niemann-Pick C1-like 1 (NPC1L1), the inhibitory target of ezetimibe (EZE), is a critical sterol transporter of cholesterol absorption. Intestinal NPC1L1 facilitates the absorption of cholesterol, whereas hepatic NPC1L1 promotes cholesterol uptake by hepatocytes and reduces bile cholesterol supersaturation. The potential of hepatic NPC1L1 to prevent CGD has yet to be established due to its absence in the mice model. In this study, we generated mice expressing hepatic NPC1L1 using adeno-associated virus (AAV) gene delivery. The biliary cholesterol saturations and gallstone formations were explored under chow diet and lithogenic diet (LD) with or without EZE treatment. The long-term (8-week) LD-fed AAV-mNPC1L1 mice exhibited no significant differences in biliary cholesterol saturation and gallstone formation compared to WT mice. EZE effectively prevented CGD in both WT and AAV-mNPC1L1 mice. Mechanistically, prolonged LD feeding induced the degradation of hepatic NPC1L1, whereas short-term (2-week) LD feeding preserved the expression of hepatic NPC1L1. In conclusion, our findings suggest that hepatic NPC1L1 is unable to prevent CGD, whereas EZE functions as an efficient bile cholesterol desaturator during CGD development.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Guoqiang Xu
- Corresponding author. Department of Gastroenterology, the First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou 310006, Zhejiang, China.
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2
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Mo P, Chen H, Jiang X, Hu F, Zhang F, Shan G, Chen W, Li S, Li Y, Xu G. FGF15 promotes hepatic NPC1L1 degradation in lithogenic diet-fed mice. Lipids Health Dis 2022; 21:97. [PMID: 36209166 PMCID: PMC9547418 DOI: 10.1186/s12944-022-01709-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 09/26/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cholesterol gallstone disease (CGD) is accompanied by biliary cholesterol supersaturation. Hepatic Niemann-Pick C1-like 1 (NPC1L1), which is present in humans but not in wild-type (WT) mice, promotes hepatocyte cholesterol uptake and decreases biliary cholesterol supersaturation. In contrast, intestinal NPC1L1 promotes intestinal cholesterol absorption, increasing biliary cholesterol supersaturation. Ezetimibe (EZE) can inhibit both hepatic and intestinal NPC1L1. However, whether hepatic NPC1L1 can affect CGD progress remains unknown. METHODS Mice expressing hepatic NPC1L1 (NPC1L1hepatic-OE mice) were generated using Adeno-associated viruses (AAV) gene delivery. The protein level and function of hepatic NPC1L1 were examined under chow diet, high fat-cholesterol diet (HFCD), and lithogenic diet (LD) feeding. Gallstone formation rates were examined with or without EZE treatment. Fibroblast growth factor 15 (FGF15) treatment and inhibition of fibroblast growth factor receptor 4 (FGFR4) were applied to verify the mechanism of hepatic NPC1L1 degradation. RESULTS The HFCD-fed NPC1L1hepatic-OE mice retained the biliary cholesterol desaturation function of hepatic NPC1L1, whereas EZE treatment decreased biliary cholesterol saturation and did not cause CGD. The ubiquitination and degradation of hepatic NPC1L1 were discovered in LD-fed NPC1L1hepatic-OE mice. Treatment of FGF15 during HFCD feeding and inhibition of FGFR4 during LD feeding could affect the protein level and function of hepatic NPC1L1. CONCLUSIONS LD induces the ubiquitination and degradation of hepatic NPC1L1 via the FGF15-FGFR4 pathway. EZE may act as an effective preventative agent for CGD.
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Affiliation(s)
- Pingfan Mo
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Hongtan Chen
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Xin Jiang
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Fengling Hu
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Fenming Zhang
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Guodong Shan
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Wenguo Chen
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Sha Li
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China
| | - Yiqiao Li
- Urology& Nephrology Center, Department of Nephrology, Zhejiang Provincial People's Hospital and Hangzhou Medical College Affiliated People's Hospital, 158 Shangtang Road, Hangzhou, 310014, Zhejiang, China.
| | - Guoqiang Xu
- Department of Gastroenterology, Zhejiang University School of Medicine, The First Affiliated Hospital, 79 Qingchun Road, Hangzhou, 310006, Zhejiang, China.
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3
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Kaushik P, Ahlawat P, Singh K, Singh R. Chemical constituents, pharmacological activities, and uses of common ayurvedic medicinal plants: a future source of new drugs. ADVANCES IN TRADITIONAL MEDICINE 2021. [DOI: 10.1007/s13596-021-00621-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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4
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Rosa L, Lobos-González L, Muñoz-Durango N, García P, Bizama C, Gómez N, González X, Wichmann IA, Saavedra N, Guevara F, Villegas J, Arrese M, Ferreccio C, Kalergis AM, Miquel JF, Espinoza JA, Roa JC. Evaluation of the chemopreventive potentials of ezetimibe and aspirin in a novel mouse model of gallbladder preneoplasia. Mol Oncol 2020; 14:2834-2852. [PMID: 33326125 PMCID: PMC7607176 DOI: 10.1002/1878-0261.12766] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/04/2020] [Accepted: 06/14/2020] [Indexed: 12/24/2022] Open
Abstract
Gallbladder stones (cholecystolithiasis) are the main risk factor for gallbladder cancer (GBC), a lethal biliary malignancy with poor survival rates worldwide. Gallbladder stones are thought to damage the gallbladder epithelium and trigger chronic inflammation. Preneoplastic lesions that arise in such an inflammatory microenvironment can eventually develop into invasive carcinoma, through mechanisms that are not fully understood. Here, we developed a novel gallbladder preneoplasia mouse model through the administration of two lithogenic diets (a low‐ or a high‐cholesterol diet) in wild‐type C57BL/6 mice over a period of 9 months. Additionally, we evaluated the chemopreventive potentials of the anti‐inflammatory drug aspirin and the cholesterol absorption inhibitor ezetimibe. Both lithogenic diets induced early formation of gallbladder stones, together with extensive inflammatory changes and widespread induction of metaplasia, an epithelial adaptation to tissue injury. Dysplastic lesions were presented only in mice fed with high‐cholesterol diet (62.5%) in late stages (9th month), and no invasive carcinoma was observed at any stage. The cholesterol absorption inhibitor ezetimibe inhibited gallbladder stone formation and completely prevented the onset of metaplasia and dysplasia in both lithogenic diets, whereas aspirin partially reduced metaplasia development only in the low‐cholesterol diet setting. This model recapitulates several of the structural and inflammatory findings observed in human cholecystolithiasic gallbladders, making it relevant for the study of gallbladder carcinogenesis. In addition, our results suggest that the use of cholesterol absorption inhibitors and anti‐inflammatory drugs can be evaluated as chemopreventive strategies to reduce the burden of GBC among high‐risk populations.
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Affiliation(s)
- Lorena Rosa
- Doctorado en Ciencias mención Biología Celular y Molecular Aplicada, Universidad de La Frontera, Temuco, Chile.,Departamento de Patología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Lorena Lobos-González
- Centro de Medicina Regenerativa, Facultad de Medicina-Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile
| | - Natalia Muñoz-Durango
- Millennium Institute of Immunology and Immunotherapy (IMII), Santiago, Chile.,Departmento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Patricia García
- Departamento de Patología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina Bizama
- Departamento de Patología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Natalia Gómez
- Departamento de Patología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ximena González
- Departamento de Patología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ignacio A Wichmann
- Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile.,Departamento de Hematología-Oncología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás Saavedra
- Departamento de Ciencias Básicas, Centro de Biología Molecular y Farmacogenética, BIOREN, Universidad de La Frontera, Temuco, Chile
| | | | - Jaime Villegas
- Fundación Ciencia & Vida, Santiago, Chile.,Centro de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - Marco Arrese
- Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Catterina Ferreccio
- Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile.,Departamento de Salud Publica, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M Kalergis
- Millennium Institute of Immunology and Immunotherapy (IMII), Santiago, Chile.,Departmento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departmento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Francisco Miquel
- Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jaime A Espinoza
- SciLifeLab, Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Juan C Roa
- Departamento de Patología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Han T, Lv Y, Wang S, Hu T, Hong H, Fu Z. Pioglitazone prevents cholesterol gallstone formation through the regulation of cholesterol homeostasis in guinea pigs with a lithogenic diet. Lipids Health Dis 2019; 18:218. [PMID: 31829191 PMCID: PMC6907187 DOI: 10.1186/s12944-019-1159-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/29/2019] [Indexed: 02/07/2023] Open
Abstract
Background The cholesterol gallstones diseases (CGD) is highly correlated with metabolic syndrome and type 2 diabetes. The present study aimed to investigate preventive effects of pioglitazone (PIO), an antidiabetic drug, on the CGD in guinea pigs fed with a lithogenic diet (LD). Methods The guinea pigs were fed with the LD for 8 weeks. All guinea pigs were grouped as follows: low fat diet; LD; LD plus PIO (4 mg/kg); LD plus PIO (8 mg/kg); LD plus ezetimibe (EZE) (2 mg/kg). Gallbladder stones were observed using microscopy. The profile of biliary composition, and blood glucose, insulin and lipid were analyzed. The liver or ileum was harvested for determinations of hydroxyl-methyl-glutaryl-CoA reductase (HMGCR), sterol regulatory element-binding proteins 2 (SREBP2), 7α-hydroxylase (CYP7A1), adenosine triphosphate-binding cassette (ABC) sterol transporters G5 and G8 (ABCG5, ABCG8), bile salt export pump (BSEP), Niemann-Pick C1-Like 1 (NPC1L1) and acetyl-coenzyme A cholesterol acyltransferase (ACAT2) by Western blot. The gallbladders were used for histological examination. Results The LD successfully induced gallstone. Both pioglitazone and ezetimibe prevented gallstone formation, as well as hepatic and cholecystic damages. Pioglitazone significantly decreased HMGCR and SREBP2, but increased CYP7A1, ABCG5, ABCG8, and BSEP in the liver. Pioglitazone also remarkably decreased NPC1L1 and ACAT2, while increased ABCG5/8 in the intestine. The beneficial alterations of cholesterol and bile acids in the bile, as well as profile of glucose, insulin and lipid in the blood were found in the guinea pigs treated with pioglitazone. Conclusion Pioglitazone has a noticeable benefit towards the CGD, which is involved in changes of synthesis, transformation, absorption, and transportation of cholesterol.
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Affiliation(s)
- Tao Han
- Department of Intensive Care Unit, the First Affiliated Hospital of Nanjing Medical University, Nanjing, 210000, Jiangsu, China
| | - Yangge Lv
- Department of Pharmacology, China Pharmaceutical University, Nanjing, 210009, China
| | - Shijia Wang
- Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, 210000, Jiangsu, China
| | - Tao Hu
- Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, 210000, Jiangsu, China
| | - Hao Hong
- Department of Pharmacology, China Pharmaceutical University, Nanjing, 210009, China
| | - Zan Fu
- Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, 210000, Jiangsu, China.
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6
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Di Ciaula A, Wang DQH, Portincasa P. Cholesterol cholelithiasis: part of a systemic metabolic disease, prone to primary prevention. Expert Rev Gastroenterol Hepatol 2019; 13:157-171. [PMID: 30791781 DOI: 10.1080/17474124.2019.1549988] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cholesterol gallstone disease have relationships with various conditions linked with insulin resistance, but also with heart disease, atherosclerosis, and cancer. These associations derive from mechanisms active at a local (i.e. gallbladder, bile) and a systemic level and are involved in inflammation, hormones, nuclear receptors, signaling molecules, epigenetic modulation of gene expression, and gut microbiota. Despite advanced knowledge of these pathways, the available therapeutic options for symptomatic gallstone patients remain limited. Therapy includes oral litholysis by the bile acid ursodeoxycholic acid (UDCA) in a small subgroup of patients at high risk of postdissolution recurrence, or laparoscopic cholecystectomy, which is the therapeutic radical gold standard treatment. Cholecystectomy, however, may not be a neutral event, and potentially generates health problems, including the metabolic syndrome. Areas covered: Several studies on risk factors and pathogenesis of cholesterol gallstone disease, acting at a systemic level have been reviewed through a PubMed search. Authors have focused on primary prevention and novel potential therapeutic strategies. Expert commentary: The ultimate goal appears to target the manageable systemic mechanisms responsible for gallstone occurrence, pointing to primary prevention measures. Changes must target lifestyles, as well as experimenting innovative pharmacological tools in subgroups of patients at high risk of developing gallstones.
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Affiliation(s)
- Agostino Di Ciaula
- a Division of Internal Medicine , Hospital of Bisceglie , Bisceglie , Italy
| | - David Q-H Wang
- b Department of Medicine, Division of Gastroenterology and Liver Diseases , Marion Bessin Liver Research Center, Albert Einstein College of Medicine , Bronx , NY , USA
| | - Piero Portincasa
- c Department of Biomedical Sciences and Human Oncology, Clinica Medica "A. Murri" , University of Bari Medical School , Bari , Italy
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Ren S, Yan X, Ma J, Pan Y, Zhang W, Wang D, Fei Z, Liu X. Defatted walnut powder extract reduces cholesterol gallstones formation in C57BL/6 mice by downregulating the levels of ABCG5/8 in the liver and NPC1L1 in the intestine. J Funct Foods 2018. [DOI: 10.1016/j.jff.2018.06.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Peroxisome Proliferator-Activated Receptor- γ Prevents Cholesterol Gallstone Formation in C57bl Mice by Regulating Bile Acid Synthesis and Enterohepatic Circulation. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7475626. [PMID: 30105244 PMCID: PMC6076980 DOI: 10.1155/2018/7475626] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 06/13/2018] [Accepted: 06/27/2018] [Indexed: 12/28/2022]
Abstract
To investigate the role of the peroxisome proliferator-activated receptor-γ (PPARγ) in the progression of cholesterol gallstone disease (CGD), C57bl/6J mice were randomized to the following groups (n=7/group): L (lithogenic diet, LGD), LM (LGD+pioglitazone), CM (chow diet+pioglitazone), and NC (normal control, chow diet). Gallbladder stones were observed by microscopy. Histological gallbladder changes were assessed. Bile acids (BA) and cholesterol were measured in the serum, bile, and feces. Proteins and mRNA expression of genes involved in BA metabolism and enterohepatic circulation were assessed by western blotting and real-time RT-PCR. PPARγ activation was performed in LO2 cell by lentivirus transfection and in Caco2 cell by PPARγ agonist treatment. Downregulation of farnesoid X receptor (FXR) by small interference RNA (siRNA) was performed in L02 cells and Caco2 cells, respectively. Results showed that pharmacological activation of PPARγ by pioglitazone prevents cholesterol gallstone formation by increasing biliary BA synthesis and enterohepatic circulation. Activated PPARγ induced the expression of genes involved in enterohepatic circulation and bile acid synthesis (like PCG1α, BSEP, MRP2, MRP3, MRP4, NTCP, CYP7A1, CYP27A1, ASBT, OSTα, and OSTβ). Downregulation of FXR repressed expression of partial genes involved in BA enterohepatic circulation. These findings suggest a new function of PPARγ in preventing CGD by handling BA synthesis and transport through a FXR dependent or independent pathway.
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9
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Abstract
PURPOSE OF REVIEW The establishment of mouse models of gallstones, and the contribution of mouse models to genetic studies of gallstone disease, as well as the latest advances in the pathophysiology of gallstones from mouse experiments are summarized. RECENT FINDINGS The combined uses of genomic strategies and phenotypic studies in mice have successfully led to the identification of many Lith genes, which pave the way for the discovery of human LITH genes. The physical-chemical, genetic, and molecular biological studies of gallstone disease in mice with knockout or transgene of specific target genes have provided many novel insights into the complex pathophysiological mechanisms of this very common hepatobiliary disease worldwide, showing that interactions of five primary defects play a critical role in the pathogenesis of cholesterol gallstones. Based on mouse studies, a new concept has been proposed that hepatic hypersecretion of biliary cholesterol is induced by multiple Lith genes, with insulin resistance as part of the metabolic syndrome interacting with cholelithogenic environmental factors to cause the phenotype. SUMMARY The mouse model of gallstones is crucial for elucidating the physical-chemical and genetic mechanisms of cholesterol crystallization and gallstone formation, which greatly increase our understanding of the pathogenesis of this disease in humans.
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10
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Abstract
PURPOSE OF REVIEW Gallstone disease is a major epidemiologic and economic burden worldwide, and the most frequent form is cholesterol gallstone disease. RECENT FINDINGS Major pathogenetic factors for cholesterol gallstones include a genetic background, hepatic hypersecretion of cholesterol, and supersaturated bile which give life to precipitating cholesterol crystals that accumulate and grow in a sluggish gallbladder. Additional factors include mucin and inflammatory changes in the gallbladder, slow intestinal motility, increased intestinal absorption of cholesterol, and altered gut microbiota. Mechanisms of disease are linked with insulin resistance, obesity, the metabolic syndrome, and type 2 diabetes. The role of nuclear receptors, signaling pathways, gut microbiota, and epigenome are being actively investigated. SUMMARY Ongoing research on cholesterol gallstone disease is intensively investigating several pathogenic mechanisms, associated metabolic disorders, new therapeutic approaches, and novel strategies for primary prevention, including lifestyles.
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Affiliation(s)
| | - David Q.-H. Wang
- Department of Medicine, Division of Gastroenterology and Liver Diseases, Marion Bessin Liver Research Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Piero Portincasa
- Department of Biomedical Sciences and Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, Bari, Italy
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Abstract
The high prevalence of cholesterol gallstones, the availability of new information about pathogenesis, and the relevant health costs due to the management of cholelithiasis in both children and adults contribute to a growing interest in this disease. From an epidemiologic point of view, the risk of gallstones has been associated with higher risk of incident ischemic heart disease, total mortality, and disease-specific mortality (including cancer) independently from the presence of traditional risk factors such as body weight, lifestyle, diabetes, and dyslipidemia. This evidence points to the existence of complex pathogenic pathways linking the occurrence of gallstones to altered systemic homeostasis involving multiple organs and dynamics. In fact, the formation of gallstones is secondary to local factors strictly dependent on the gallbladder (that is, impaired smooth muscle function, wall inflammation, and intraluminal mucin accumulation) and bile (that is, supersaturation in cholesterol and precipitation of solid crystals) but also to "extra-gallbladder" features such as gene polymorphism, epigenetic factors, expression and activity of nuclear receptors, hormonal factors (in particular, insulin resistance), multi-level alterations in cholesterol metabolism, altered intestinal motility, and variations in gut microbiota. Of note, the majority of these factors are potentially manageable. Thus, cholelithiasis appears as the expression of systemic unbalances that, besides the classic therapeutic approaches to patients with clinical evidence of symptomatic disease or complications (surgery and, in a small subgroup of subjects, oral litholysis with bile acids), could be managed with tools oriented to primary prevention (changes in diet and lifestyle and pharmacologic prevention in subgroups at high risk), and there could be relevant implications in reducing both prevalence and health costs.
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Affiliation(s)
- Agostino Di Ciaula
- Division of Internal Medicine - Hospital of Bisceglie, ASL BAT, Bisceglie, Italy
| | - Piero Portincasa
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Bari, Italy
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12
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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.
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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
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Hepatitis C virus may have an entero-hepatic cycle which could be blocked with ezetimibe. Med Hypotheses 2017; 102:51-55. [PMID: 28478831 DOI: 10.1016/j.mehy.2017.03.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 03/08/2017] [Indexed: 12/11/2022]
Abstract
Hepatitis C virus can lead to chronic infection, cirrhosis and hepatocellular carcinoma. With more than 170 million people infected worldwide, eradication remains a challenge even with the revolutionary current direct antiviral agents (DAAs). The risk of resistance, the safety profile in some populations, the genotype specificity and the high price of current DAAs explain why there is still interest in developing host targeting agents (HTA) that may help overcome some of these difficulties. Specifically, targeting the entry of HCV to the cell seems like a promising strategy. Recently it has been shown that the cholesterol transporter NPC1L1, a protein located in the small bowel epithelium and in the canalicular membrane of the hepatocyte is also an HCV receptor. Just as this protein is key in the entero-hepatic cycle of cholesterol, we hypothesize that there is an entero-hepatic cycle of HCV that could be disrupted by blocking NPC1L1 with ezetimibe, an already approved and readily available safe drug. Ezetimibe, either alone or in combination with DAAs, could decrease relapse rates, reduce resistance and even make treatments cheaper.
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Jakulj L, van Dijk TH, de Boer JF, Kootte RS, Schonewille M, Paalvast Y, Boer T, Bloks VW, Boverhof R, Nieuwdorp M, Beuers UHW, Stroes ESG, Groen AK. Transintestinal Cholesterol Transport Is Active in Mice and Humans and Controls Ezetimibe-Induced Fecal Neutral Sterol Excretion. Cell Metab 2016; 24:783-794. [PMID: 27818259 DOI: 10.1016/j.cmet.2016.10.001] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 05/09/2016] [Accepted: 09/30/2016] [Indexed: 01/10/2023]
Abstract
Except for conversion to bile salts, there is no major cholesterol degradation pathway in mammals. Efficient excretion from the body is therefore a crucial element in cholesterol homeostasis. Yet, the existence and importance of cholesterol degradation pathways in humans is a matter of debate. We quantified cholesterol fluxes in 15 male volunteers using a cholesterol balance approach. Ten participants repeated the protocol after 4 weeks of treatment with ezetimibe, an inhibitor of intestinal and biliary cholesterol absorption. Under basal conditions, about 65% of daily fecal neutral sterol excretion was bile derived, with the remainder being contributed by direct transintestinal cholesterol excretion (TICE). Surprisingly, ezetimibe induced a 4-fold increase in cholesterol elimination via TICE. Mouse studies revealed that most of ezetimibe-induced TICE flux is mediated by the cholesterol transporter Abcg5/Abcg8. In conclusion, TICE is active in humans and may serve as a novel target to stimulate cholesterol elimination in patients at risk for cardiovascular disease.
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Affiliation(s)
- Lily Jakulj
- Department of Vascular Medicine, Academic Medical Center, Amsterdam 1105AZ, the Netherlands
| | - Theo H van Dijk
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Jan Freark de Boer
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Ruud S Kootte
- Department of Vascular Medicine, Academic Medical Center, Amsterdam 1105AZ, the Netherlands
| | - Marleen Schonewille
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Yared Paalvast
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Theo Boer
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Vincent W Bloks
- Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Renze Boverhof
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands
| | - Max Nieuwdorp
- Department of Vascular Medicine, Academic Medical Center, Amsterdam 1105AZ, the Netherlands
| | - Ulrich H W Beuers
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam 1105AZ, the Netherlands
| | - Erik S G Stroes
- Department of Vascular Medicine, Academic Medical Center, Amsterdam 1105AZ, the Netherlands
| | - Albert K Groen
- Department of Vascular Medicine, Academic Medical Center, Amsterdam 1105AZ, the Netherlands; Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands; Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen 9713ZG, the Netherlands; Amsterdam Diabetes Research Center, Academic Medical Center, Amsterdam 1105AZ, the Netherlands; Groningen Center of Systems Biology, University Medical Center Groningen, Groningen 9713ZG, the Netherlands.
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15
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EASL Clinical Practice Guidelines on the prevention, diagnosis and treatment of gallstones. J Hepatol 2016; 65:146-181. [PMID: 27085810 DOI: 10.1016/j.jhep.2016.03.005] [Citation(s) in RCA: 266] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 03/09/2016] [Indexed: 02/06/2023]
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16
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Qamar A, Usmani A, Waqar H, Siddiqui A, Kumar H. Ameliorating effect of Allium Sativum on high-fat diet induced fatty liver in albino rats. Pak J Med Sci 2016; 32:403-7. [PMID: 27182249 PMCID: PMC4859032 DOI: 10.12669/pjms.322.9025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Objective: To assess the hepatoprotective effect provided by fresh garlic on fatty liver induced by high-fat diet. Methods: This experimental study was carried out at BMSI, JPMC from October to November 2008. Thirty adult albino rats, 200-240 gram weight, were divided into three groups. Group A received control diet, Group B received high-fat diet (20 mg butter/100 gm diet) and Group C received high-fat diet with fresh garlic (20 mg butter with 6 gm fresh garlic/100 gm diet). The groups were further divided on the basis of duration of treatment, four weeks and eight weeks respectively. The rats were sacrificed, liver removed, weighed and relative liver weight calculated. Hepatic tissue was processed and tissue slides stained with haematoxylin and eosin. Results: There was significant increase in relative liver weight in group B animals as compared to the control animals, which decreased significantly in group C. Haematoxylin and eosin stained sections revealed ballooned hepatocytes having vesicular appearance with pyknotic nuclei in high-fat group which were preserved to a great extent in group C animals. Conclusion: This study has shown that use of fresh garlic along with high-fat diet prevents its damaging effects on liver to a great extent.
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Affiliation(s)
- Aisha Qamar
- Dr. Ayesha Qamar, M Phil, Department of Anatomy, Bahria University Medical and Dental College, Karachi - Pakistan
| | - Ambreen Usmani
- Dr. Ambreen Usmani, M Phil, Department of Anatomy, Bahria University Medical and Dental College, Karachi - Pakistan
| | - Humera Waqar
- Dr. Humera Waqar, MBBS, Department of Anatomy, Bahria University Medical and Dental College, Karachi - Pakistan
| | - Asma Siddiqui
- Dr. Asma Siddiqui, M Phil, Department of Anatomy, Bahria University Medical and Dental College, Karachi - Pakistan
| | - Hemant Kumar
- Dr. Hemant Kumar, M Phil, Department of Anatomy, Hamdard University, Karachi - Pakistan
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Portincasa P, Di Ciaula A, de Bari O, Garruti G, Palmieri VO, Wang DQH. Management of gallstones and its related complications. Expert Rev Gastroenterol Hepatol 2016; 10:93-112. [PMID: 26560258 DOI: 10.1586/17474124.2016.1109445] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The majority of gallstone patients remain asymptomatic; however, interest toward the gallstone disease is continuing because of the high worldwide prevalence and management costs and the development of gallstone symptoms and complications. For cholesterol gallstone disease, moreover, a strong link exists between this disease and highly prevalent metabolic disorders such as obesity, dyslipidemia, type 2 diabetes, hyperinsulinemia, hypertriglyceridemia and the metabolic syndrome. Information on the natural history as well as the diagnostic, surgical (mainly laparoscopic cholecystectomy) and medical tools available to facilitate adequate management of cholelithiasis and its complications are, therefore, crucial to prevent the negative outcomes of gallstone disease. Moreover, some risk factors for gallstone disease are modifiable and some preventive strategies have become necessary to reduce the onset and the severity of complications.
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Affiliation(s)
- P Portincasa
- a Department of Biomedical Sciences and Human Oncology, Clinica Medica "A. Murri" , University of Bari Medical School , Bari , Italy
| | - A Di Ciaula
- b Division of Internal Medicine , Hospital of Bisceglie , Bisceglie , Italy
| | - O de Bari
- a Department of Biomedical Sciences and Human Oncology, Clinica Medica "A. Murri" , University of Bari Medical School , Bari , Italy
- d Department of Internal Medicine, Division of Gastroenterology and Hepatology , Saint Louis University School of Medicine , St. Louis , MO , USA
| | - G Garruti
- c Department of Emergency and Organ Transplants, Section of Endocrinology, Andrology and Metabolic Diseases , University of Bari Medical School , Bari , Italy
| | - V O Palmieri
- a Department of Biomedical Sciences and Human Oncology, Clinica Medica "A. Murri" , University of Bari Medical School , Bari , Italy
| | - D Q-H Wang
- d Department of Internal Medicine, Division of Gastroenterology and Hepatology , Saint Louis University School of Medicine , St. Louis , MO , USA
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18
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Gil-Ramírez A, Caz V, Martin-Hernandez R, Marín FR, Largo C, Rodríguez-Casado A, Tabernero M, Ruiz-Rodríguez A, Reglero G, Soler-Rivas C. Modulation of cholesterol-related gene expression by ergosterol and ergosterol-enriched extracts obtained from Agaricus bisporus. Eur J Nutr 2015; 55:1041-57. [DOI: 10.1007/s00394-015-0918-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 04/25/2015] [Indexed: 01/31/2023]
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19
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Lauridsen BK, Stender S, Frikke-Schmidt R, Nordestgaard BG, Tybjærg-Hansen A. Genetic variation in the cholesterol transporter NPC1L1, ischaemic vascular disease, and gallstone disease. Eur Heart J 2015; 36:1601-8. [DOI: 10.1093/eurheartj/ehv108] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 03/17/2015] [Indexed: 11/12/2022] Open
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20
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de Bari O, Wang HH, Portincasa P, Paik CN, Liu M, Wang DQH. Ezetimibe prevents the formation of oestrogen-induced cholesterol gallstones in mice. Eur J Clin Invest 2014; 44:1159-68. [PMID: 25303682 PMCID: PMC4659711 DOI: 10.1111/eci.12350] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 10/03/2014] [Indexed: 12/15/2022]
Abstract
BACKGROUND Oestrogen is an important risk factor for cholesterol cholelithiasis not only in women of childbearing age taking oral contraceptives and postmenopausal women undergoing hormone replacement therapy, but also in male patients receiving oestrogen therapy for prostatic cancer. In women, hormonal changes occurring during pregnancy markedly increase the risk of developing gallstones. We investigated whether the potent cholesterol absorption inhibitor ezetimibe could prevent the formation of oestrogen-induced cholesterol gallstones in mice. DESIGN Following ovariectomy, female AKR mice were implanted subcutaneously with pellets releasing 17β-estradiol at 6 μg/day and fed a lithogenic diet supplemented with ezetimibe in doses of 0 or 8 mg/kg/day for 8 weeks. Cholesterol crystallization and gallstone prevalence, lipid concentrations and composition in bile, and biliary lipid output were analysed by physical-chemical methods. Intestinal cholesterol absorption efficiency was determined by faecal dual-isotope ratio methods. RESULTS Ezetimibe inhibited intestinal cholesterol absorption, while significantly reducing hepatic secretion of biliary cholesterol. Consequently, bile was desaturated through the formation of numerous unsaturated micelles and gallstones were prevented by ezetimibe in mice exposed to high doses of oestrogen and fed the lithogenic diet. Ezetimibe did not influence mRNA levels of the classical oestrogen receptors α (ERα) and ERβ, as well as a novel oestrogen receptor the G protein-coupled receptor 30 (GPR30) in the liver. CONCLUSIONS Ezetimibe protects against the oestrogen-mediated lithogenic actions on gallstone formation in mice. Our finding may provide an efficacious novel strategy for the prevention of cholesterol gallstones in high-risk subjects, especially those exposed to high levels of oestrogen.
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Affiliation(s)
- Ornella de Bari
- Department of Internal Medicine, Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, St. Louis, MO, USA
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21
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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]
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22
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Stokes CS, Gluud LL, Casper M, Lammert F. Pharmacological interventions for the primary prevention of gallbladder stones in adults. Hippokratia 2014. [DOI: 10.1002/14651858.cd011037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Caroline S. Stokes
- Saarland University Hospital; Department of Medicine II; Kirrberger Str. 1 Homburg/Saar Germany 66421
| | - Lise Lotte Gluud
- Copenhagen University Hospital Hvidovre; Gastro Unit, Medical Division; Kettegaards Alle Hvidovre Denmark 2650
| | - Markus Casper
- Saarland University Hospital; Department of Medicine II; Kirrberger Str. 1 Homburg/Saar Germany 66421
| | - Frank Lammert
- Saarland University Hospital; Department of Medicine II; Kirrberger Str. 1 Homburg/Saar Germany 66421
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23
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Abstract
Polytopic transmembrane protein, Niemann-Pick C1-Like 1 (NPC1L1) is localized at the apical membrane of enterocytes and the canalicular membrane of hepatocytes. It mediates intestinal cholesterol absorption and prevents extensive loss of cholesterol by transporting biliary cholesterol into hepatocytes. NPC1L1 is a molecular target of ezetimibe, an agent for hypercholesterolemia. Recently, NPC1L1 inhibition has been shown to prevent metabolic disorders such as fatty liver disease, obesity, diabetes, and atherosclerosis. In this review, the identification and characterization of NPC1L1, NPC1L1-dependent cholesterol transport, the relationship with pathogenesis of metabolic disease and its newly introduced function for virus entry are discussed.
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Affiliation(s)
- Sung-Woo Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
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24
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Wang HH, Portincasa P, de Bari O, Liu KJ, Garruti G, Neuschwander-Tetri BA, Wang DQH. Prevention of cholesterol gallstones by inhibiting hepatic biosynthesis and intestinal absorption of cholesterol. Eur J Clin Invest 2013; 43:413-26. [PMID: 23419155 PMCID: PMC3996849 DOI: 10.1111/eci.12058] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 01/22/2013] [Indexed: 12/14/2022]
Abstract
BACKGROUND Cholesterol cholelithiasis is a multifactorial disease influenced by a complex interaction of genetic and environmental factors and represents a failure of biliary cholesterol homoeostasis in which the physical-chemical balance of cholesterol solubility in bile is disturbed. DESIGN The primary pathophysiologic event is persistent hepatic hypersecretion of biliary cholesterol, which has both hepatic and small intestinal components. The majority of the environmental factors are probably related to Western-type dietary habits, including excess cholesterol consumption. RESULTS Laparoscopic cholecystectomy, one of the most commonly performed surgical procedures in the United States, is nowadays a major treatment for gallstones. However, it is invasive and can cause surgical complications, and not all patients with symptomatic gallstones are candidates for surgery. The hydrophilic bile acid, ursodeoxycholic acid (UDCA), has been employed as first-line pharmacological therapy in a subgroup of symptomatic patients with small, radiolucent cholesterol gallstones. Long-term administration of UDCA can promote the dissolution of cholesterol gallstones. However, the optimal use of UDCA is not always achieved in clinical practice because of failure to titrate the dose adequately. CONCLUSIONS Therefore, the development of novel, effective and noninvasive therapies is crucial for reducing the costs of health care associated with gallstones. In this review, we summarize recent progress in investigating the inhibitory effects of ezetimibe and statins on intestinal absorption and hepatic biosynthesis of cholesterol, respectively, for the treatment of gallstones, as well as in elucidating their molecular mechanisms by which combination therapy could prevent this very common liver disease worldwide.
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Affiliation(s)
- Helen H Wang
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
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25
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Castro-Torres IG, De la O-Arciniega M, Gallegos-Estudillo J, Naranjo-Rodríguez EB, Domínguez-Ortíz MÁ. Raphanus sativus L. var niger as a source of phytochemicals for the prevention of cholesterol gallstones. Phytother Res 2013; 28:167-71. [PMID: 23495001 DOI: 10.1002/ptr.4964] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 01/27/2013] [Accepted: 02/01/2013] [Indexed: 12/21/2022]
Abstract
Raphanus sativus L. var niger (black radish) is a plant of the cruciferous family with important ethnobotanical uses for the treatment of gallstones in Mexican traditional medicine. It has been established that the juice of black radish decreases cholesterol levels in plasma and dissolves gallstones in mice. Glucosinolates, the main secondary metabolites of black radish, can hydrolyze into its respective isothiocyanates and have already demonstrated antioxidant properties as well as their ability to diminish hepatic cholesterol levels; such therapeutic effects can prevent the formation of cholesterol gallstones. This disease is considered a current problem of public health. In the present review, we analyze and discuss the therapeutic effects of the main glucosinolates of black radish, as well as the effects that this plant has on cholesterol gallstones disease.
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26
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Stender S, Frikke-Schmidt R, Benn M, Nordestgaard BG, Tybjærg-Hansen A. Low-density lipoprotein cholesterol and risk of gallstone disease: a Mendelian randomization study and meta-analyses. J Hepatol 2013; 58:126-33. [PMID: 22922093 DOI: 10.1016/j.jhep.2012.08.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 07/22/2012] [Accepted: 08/09/2012] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS Drugs which reduce plasma low-density lipoprotein cholesterol (LDL-C) may protect against gallstone disease. Whether plasma levels of LDL-C per se predict risk of gallstone disease remains unclear. We tested the hypothesis that elevated LDL-C is a causal risk factor for symptomatic gallstone disease. METHODS We used a Mendelian randomization approach and genotyped 63,051 individuals from a prospective cohort study of the general Danish population, including 3323 subjects with symptomatic gallstones. We selected eight genetic variants in APOE, APOB, LDLR, and PCSK9 affecting LDL-C. Furthermore, studies of APOE rs429358/rs7412 (defining ε2/ε3/ε4 alleles; 12 studies) and APOB rs693 (eight studies) were included in meta-analyses. RESULTS The observational hazard ratio (HR) for symptomatic gallstone disease for the fifth versus first quintile of LDL-C was 0.94 (95% confidence interval: 0.76-1.17), despite a corresponding 134% increase in LDL-C. Furthermore, although individual genetic variants in APOE, APOB, LDLR, and PCSK9 associated with stepwise increases/decreases in LDL-C of up to +59% compared with non-carriers (p <0.001), none predicted the risk of symptomatic gallstone disease. Combining all variants into 10 genotypes, carriers of 9 versus ⩽3 LDL-C increasing alleles associated with 41% increased LDL-C (p <0.001), but predicted a HR for symptomatic gallstone disease of 1.09 (0.70-1.69). Finally, in meta-analyses, random effects odds ratios for gallstone disease were 0.91 (0.78-1.06) for carriers of APOE ε4 versus non-carriers, and 1.25 (0.95-1.63) for APOB rs693 CT+TT versus CC. CONCLUSIONS Results from the observational study, genetic studies, and meta-analyses suggest that elevated plasma levels of LDL-C are not causally associated with increased risk of symptomatic gallstone disease.
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Affiliation(s)
- Stefan Stender
- Department of Clinical Biochemistry, Rigshospitalet, Denmark
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27
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Xia X, Jung D, Webb P, Zhang A, Zhang B, Li L, Ayers SD, Gabbi C, Ueno Y, Gustafsson JÅ, Alpini G, Moore DD, LeSage GD. Liver X receptor β and peroxisome proliferator-activated receptor δ regulate cholesterol transport in murine cholangiocytes. Hepatology 2012; 56:2288-96. [PMID: 22729460 PMCID: PMC3469731 DOI: 10.1002/hep.25919] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 06/03/2012] [Indexed: 02/02/2023]
Abstract
UNLABELLED Nuclear receptors (NRs) play crucial roles in the regulation of hepatic cholesterol synthesis, metabolism, and conversion to bile acids, but their actions in cholangiocytes have not been examined. In this study, we investigated the roles of NRs in cholangiocyte physiology and cholesterol metabolism and flux. We examined the expression of NRs and other genes involved in cholesterol homeostasis in freshly isolated and cultured murine cholangiocytes and found that these cells express a specific subset of NRs, including liver X receptor (LXR) β and peroxisome proliferator-activated receptor (PPAR) δ. Activation of LXRβ and/or PPARδ in cholangiocytes induces ATP-binding cassette cholesterol transporter A1 (ABCA1) and increases cholesterol export at the basolateral compartment in polarized cultured cholangiocytes. In addition, PPARδ induces Niemann-Pick C1-like L1 (NPC1L1), which imports cholesterol into cholangiocytes and is expressed on the apical cholangiocyte membrane via specific interaction with a peroxisome proliferator-activated response element (PPRE) within the NPC1L1 promoter. CONCLUSION We propose that (1) LXRβ and PPARδ coordinate NPC1L1/ABCA1-dependent vectorial cholesterol flux from bile through cholangiocytes and (2) manipulation of these processes may influence bile composition with important applications in cholestatic liver disease and gallstone disease, two serious health concerns for humans.
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Affiliation(s)
- Xuefeng Xia
- Methodist Hospital Research Institute, Weill Cornell School of Medicine, Houston, TX 77030, USA.
| | - Dongju Jung
- Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030
| | - Paul Webb
- The Methodist Hospital Research Institute, Weill Cornell School of Medicine, 6670 Bertner Ave, Houston, TX 77030
| | - Aijun Zhang
- The Methodist Hospital Research Institute, Weill Cornell School of Medicine, 6670 Bertner Ave, Houston, TX 77030
| | - Bin Zhang
- The Methodist Hospital Research Institute, Weill Cornell School of Medicine, 6670 Bertner Ave, Houston, TX 77030
| | - Lifei Li
- The First Hospital, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Stephen D. Ayers
- The Methodist Hospital Research Institute, Weill Cornell School of Medicine, 6670 Bertner Ave, Houston, TX 77030
| | - Chiara Gabbi
- Center for Nuclear Receptor and Cell Signaling, University of Houston, Calhoun Road, Houston TX77004,Karolinska Institutet, Department of Biosciences and Nutrition, NOVUM, 14186 Stockholm, Sweden
| | - Yoshiyuki Ueno
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Jan-Åke Gustafsson
- Center for Nuclear Receptor and Cell Signaling, University of Houston, Calhoun Road, Houston TX77004,Karolinska Institutet, Department of Biosciences and Nutrition, NOVUM, 14186 Stockholm, Sweden
| | - Gianfranco Alpini
- Scott & White Digestive Diseases Research Center, Temple, TX 76504,Division Research, Central Texas Veterans Health Care System, Temple, TX 76504,Department of Medicine, Texas A & M Health Science Center College of Medicine, Temple, TX 76504
| | - David D. Moore
- Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030
| | - Gene D. LeSage
- Department of Internal Medicine at East Tennessee State University’s James H. Quillen College of Medicine, Johnson City, TN 37614,Correspondence to: Xuefeng Xia, The Methodist Hospital Research Institute, 6670 Bertner Ave, R8-117, Houston, TX 77030, Telephone: 713-441-6665, Fax: 713-793-7162, and Gene LeSage, Department of Internal Medicine, East Tennessee State University, VA Bldg. 1, Box 70622, Johnson City, TN 37614, Telephone: 423-439-6282, Fax: 423-439-6387,
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28
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Jeong SU, Lee SK. [Obesity and gallbladder diseases]. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2012; 59:27-34. [PMID: 22289951 DOI: 10.4166/kjg.2012.59.1.27] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Obesity is an important health problem in the world and related to many critical diseases, such as diabetes, cardiovascular disease, and metabolic syndrome. Obesity leads to fat infiltration of multiple organs and infiltrated adipose tissue produces many cytokines resulting in the dysfunction of organs such as the gallbladder. In the biliary diseases, obesity and overweight have been known as a major risk factor for gallstones. According to current studies, obesity, insulin resistance, hyperinsulinemia, and metabolic syndrome are related to various gallbladder diseases including gallbladder stones, cholecystitis, gallbladder polyps, and gallbladder cancers. We reviewed further literature on the obesity and gallbladder diseases, in aspects of epidemiology, mechanism, pathology and prevention.
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Affiliation(s)
- Seung Uk Jeong
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
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Krawczyk M, Lütjohann D, Schirin-Sokhan R, Villarroel L, Nervi F, Pimentel F, Lammert F, Miquel JF. Phytosterol and cholesterol precursor levels indicate increased cholesterol excretion and biosynthesis in gallstone disease. Hepatology 2012; 55:1507-17. [PMID: 22213168 DOI: 10.1002/hep.25563] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 12/06/2011] [Indexed: 01/10/2023]
Abstract
UNLABELLED In hepatocytes and enterocytes sterol uptake and secretion is mediated by Niemann-Pick C1-like 1 (NPC1L1) and ATP-binding cassette (ABC)G5/8 proteins, respectively. Whereas serum levels of phytosterols represent surrogate markers for intestinal cholesterol absorption, cholesterol precursors reflect cholesterol biosynthesis. Here we compare serum and biliary sterol levels in ethnically different populations of patients with gallstone disease (GSD) and stone-free controls to identify differences in cholesterol transport and synthesis between these groups. In this case-control study four cohorts were analyzed: 112 German patients with GSD and 152 controls; two distinct Chilean ethnic groups: Hispanics (100 GSD, 100 controls), and Amerindians (20 GSD, 20 controls); additionally an 8-year follow-up of 70 Hispanics was performed. Serum sterols were measured by gas chromatography / mass spectrometry. Gallbladder bile sterol levels were analyzed in cholesterol GSD and controls. Common ABCG5/8 variants were genotyped. Comparison of serum sterols showed lower levels of phytosterols and higher levels of cholesterol precursors in GSD patients than in controls. The ratios of phytosterols to cholesterol precursors were lower in GSD patients, whereas biliary phytosterol and cholesterol concentrations were elevated as compared with controls. In the follow-up study, serum phytosterol levels were significantly lower even before GSD was detectable by ultrasound. An ethnic gradient in the ratios of phytosterols to cholesterol precursors was apparent (Germans > Hispanics > Amerindians). ABCG5/8 variants did not fully explain the sterol metabolic trait of GSD in any of the cohorts. CONCLUSION Individuals predisposed to GSD display increased biliary output of cholesterol in the setting of relatively low intestinal cholesterol absorption, indicating enhanced whole-body sterol clearance. This metabolic trait precedes gallstone formation and is a feature of ethnic groups at higher risk of cholesterol GSD.
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Affiliation(s)
- Marcin Krawczyk
- Department of Medicine II, Saarland University Medical Center, Saarland University, Homburg, Germany
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30
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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]
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31
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Portincasa P, Ciaula AD, Bonfrate L, Wang DQ. Therapy of gallstone disease: What it was, what it is, what it will be. World J Gastrointest Pharmacol Ther 2012; 3:7-20. [PMID: 22577615 PMCID: PMC3348960 DOI: 10.4292/wjgpt.v3.i2.7] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 09/21/2011] [Accepted: 09/28/2011] [Indexed: 02/06/2023] Open
Abstract
Cholesterol gallstone disease is a common clinical condition influenced by genetic factors, increasing age, female gender, and metabolic factors. Although laparoscopic cholecystectomy is currently considered the gold standard in treating patients with symptomatic gallstones, new perspectives regarding medical therapy of cholelithiasis are currently under discussion, also taking into account the pathogenesis of gallstones, the natural history of the disease and the analysis of the overall costs of therapy. A careful selection of patients may lead to successful non-surgical therapy in symptomatic subjects with a functioning gallbladder harboring small radiolucent stones. The classical oral litholysis by ursodeoxycholic acid has been recently paralleled by new experimental observations, suggesting that cholesterol-lowering agents which inhibit cholesterol synthesis (statins) or intestinal cholesterol absorption (ezetimibe), or drugs acting on specific nuclear receptors involved in cholesterol and bile acid homeostasis, might be proposed as additional approaches for treating cholesterol gallstones. In this review we discuss old, recent and future perspectives on medical treatment of cholesterol cholelithiasis.
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Affiliation(s)
- Piero Portincasa
- Piero Portincasa, Leonilde Bonfrate, Department of Biomedical Sciences and Human Oncology, Clinica Medica "A. Murri", University of Bari Medical School, Piazza Giulio Cesare 11, Policlinico, 70124 Bari, Italy
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Reshetnyak VI. Concept of the pathogenesis and treatment of cholelithiasis. World J Hepatol 2012; 4:18-34. [PMID: 22400083 PMCID: PMC3295849 DOI: 10.4254/wjh.v4.i2.18] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 11/15/2011] [Accepted: 02/24/2012] [Indexed: 02/06/2023] Open
Abstract
Gallstone disease (GD) is a chronic recurrent hepatobiliary disease, the basis for which is the impaired metabolism of cholesterol, bilirubin and bile acids, which is characterized by the formation of gallstones in the hepatic bile duct, common bile duct, or gallbladder. GD is one of the most prevalent gastrointestinal diseases with a substantial burden to health care systems. GD can result in serious outcomes, such as acute gallstone pancreatitis and gallbladder cancer. The epidemiology, pathogenesis and treatment of GD are discussed in this review. The prevalence of GD varies widely by region. The prevalence of gallstone disease has increased in recent years. This is connected with a change in lifestyle: reduction of motor activity, reduction of the physical load and changes to diets. One of the important benefits of early screening for gallstone disease is that ultrasonography can detect asymptomatic cases, which results in early treatment and the prevention of serious outcomes. The pathogenesis of GD is suggested to be multifactorial and probably develops from complex interactions between many genetic and environmental factors. It suggests that corticosteroids and oral contraceptives, which contain hormones related to steroid hormones, may be regarded as a model system of cholelithiasis development in man. The achievement in the study of the physiology of bile formation and the pathogenesis of GD has allowed expanding indications for therapeutic treatment of GD.
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Affiliation(s)
- Vasiliy Ivanovich Reshetnyak
- Vasiliy Ivanovich Reshetnyak, VA Negovsky Scientific Research Institute of General Reanimatology, Russia Academy of Medical Sciences, Moscow 107031, Russia
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Xie M, Kotecha VR, Andrade JDP, Fox JG, Carey MC. Augmented cholesterol absorption and sarcolemmal sterol enrichment slow small intestinal transit in mice, contributing to cholesterol cholelithogenesis. J Physiol 2012; 590:1811-24. [PMID: 22331417 DOI: 10.1113/jphysiol.2011.224717] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Cholesterol gallstones are associated with slow intestinal transit in humans as well as in animal models, but the molecular mechanism is unknown. We investigated in C57L/J mice whether the components of a lithogenic diet (LD; 1.0% cholesterol, 0.5% cholic acid and 17% triglycerides), as well as distal intestinal infection with Helicobacter hepaticus, influence small intestinal transit time. By quantifying the distribution of 3H-sitostanol along the length of the small intestine following intraduodenal instillation,we observed that, in both sexes, the geometric centre (dimensionless) was retarded significantly (P <0.05) by LD but not slowed further by helicobacter infection (males, 9.4±0.5 (uninfected), 9.6±0.5 (infected) on LD compared with 12.5±0.4 and 11.4±0.5 on chow). The effect of the LD was reproduced only by the binary combination of cholesterol and cholic acid. We inferred that the LD-induced cholesterol enrichment of the sarcolemmae of intestinal smooth muscle cells produced hypomotility from signal-transduction decoupling of cholecystokinin (CCK), a physiological agonist for small intestinal propulsion in mice. Treatment with ezetimibe in an amount sufficient to block intestinal cholesterol absorption caused small intestinal transit time to return to normal. In most cholesterol gallstone-prone humans, lithogenic bile carries large quantities of hepatic cholesterol into the upper small intestine continuously, thereby reproducing this dietary effect in mice. Intestinal hypomotility promotes cholelithogenesis by augmenting formation of deoxycholate, a pro-lithogenic secondary bile salt, and increasing the fraction of intestinal cholesterol absorbed.
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Affiliation(s)
- Meimin Xie
- Department of Medicine, Harvard Medical School, Boston, MA, USA
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de Bari O, Neuschwander-Tetri BA, Liu M, Portincasa P, Wang DQH. Ezetimibe: its novel effects on the prevention and the treatment of cholesterol gallstones and nonalcoholic Fatty liver disease. J Lipids 2011; 2012:302847. [PMID: 22132342 PMCID: PMC3216277 DOI: 10.1155/2012/302847] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 08/26/2011] [Indexed: 12/18/2022] Open
Abstract
The cholesterol absorption inhibitor ezetimibe can significantly reduce plasma cholesterol concentrations by inhibiting the Niemann-Pick C1-like 1 protein (NPC1L1), an intestinal sterol influx transporter that can actively facilitate the uptake of cholesterol for intestinal absorption. Unexpectedly, ezetimibe treatment also induces a complete resistance to cholesterol gallstone formation and nonalcoholic fatty liver disease (NAFLD) in addition to preventing hypercholesterolemia in mice on a Western diet. Because chylomicrons are the vehicles with which the enterocytes transport cholesterol and fatty acids into the body, ezetimibe could prevent these two most prevalent hepatobiliary diseases possibly through the regulation of chylomicron-derived cholesterol and fatty acid metabolism in the liver. It is highly likely that there is an intestinal and hepatic cross-talk through the chylomicron pathway. Therefore, understanding the molecular mechanisms whereby cholesterol and fatty acids are absorbed from the intestine could offer an efficacious novel approach to the prevention and the treatment of cholesterol gallstones and NAFLD.
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Affiliation(s)
- Ornella de Bari
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Edward Doisy Research Center, Saint Louis University School of Medicine, 1100 S. Grand Boulevard, Room 205, St. Louis, MO 63104, USA
| | - Brent A. Neuschwander-Tetri
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Edward Doisy Research Center, Saint Louis University School of Medicine, 1100 S. Grand Boulevard, Room 205, St. Louis, MO 63104, USA
| | - Min Liu
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
| | - Piero Portincasa
- Department of Internal Medicine and Public Medicine, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy
| | - David Q.-H. Wang
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Edward Doisy Research Center, Saint Louis University School of Medicine, 1100 S. Grand Boulevard, Room 205, St. Louis, MO 63104, USA
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Ahmed MH, Hamad MA, Routh C, Connolly V. Statins as potential treatment for cholesterol gallstones: an attempt to understand the underlying mechanism of actions. Expert Opin Pharmacother 2011; 12:2673-81. [PMID: 22043827 DOI: 10.1517/14656566.2011.629995] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Statin therapy is widely used across the globe for the treatment and prevention of cardiovascular disease (CVD). It is well established that statin therapy is associated with significant decreases in low-density lipoprotein cholesterol (LDL-C) and plasma cholesterol levels. Cholesterol gallstones are a common problem, resulting in hospital admission and surgery, throughout western healthcare systems. AREAS COVERED This review describes the mechanisms, and addresses the potential, for statins to be used as a treatment for gallstones. Medline was searched for the risk factors and treatment of cholesterol gallstones. EXPERT OPINION Obesity, metabolic syndrome, non-alcoholic fatty liver disease (NAFLD), insulin resistance and high-fat diets (unsaturated fats) rich in cholesterol are all associated risk factors for cholesterol gallstones. In view of the high prevalence of cholesterol gallstones, there is an urgent need to understand whether pharmacological therapies can be harnessed for the treatment of cholesterol gallstones. Gallstones are shown to be associated with an increased risk, not only of mortality, but also of CVD. Statins, widely used in prevention of CVD and hypercholesteremia, have been shown to dissolve cholesterol gallstones in animal models and human studies, highlighting the potential for a pharmacological therapy for gallstones. More studies are required to understand the role of statins in the treatment of gallstones and for comparison with current treatment strategies.
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Affiliation(s)
- Mohamed H Ahmed
- The James Cook University Hospital, Cardiothoracic Division, Department of Cardiology, Marton Road, Middlesbrough TS4 3BW, UK
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36
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The chylomicron: relationship to atherosclerosis. Int J Vasc Med 2011; 2012:784536. [PMID: 22007304 PMCID: PMC3189596 DOI: 10.1155/2012/784536] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 08/08/2011] [Indexed: 12/20/2022] Open
Abstract
The B-containing lipoproteins are the transporters of cholesterol, and the evidence suggests that the apo B48-containing postprandial chylomicron particles and the triglyceride-rich very low density lipoprotein (VLDL) particles play an important part in the development of the plaque both directly and indirectly by their impact on LDL composition. The ratio of dietary to synthesised cholesterol is variable but tightly regulated: hence intervention with diet at best reduces serum cholesterol by <20% andusually <10%. Statins are the mainstay of cholesterol reduction therapy, but they increase cholesterol absorption, an example of the relationship between synthesis and absorption. Inhibition of cholesterol absorption with Ezetimibe, an inhibitor of Niemann Pick C1-like 1 (NPC1-L1), the major regulator of cholesterol absorption, increases cholesterol synthesis and hence the value of adding an inhibitor of cholesterol absorption to an inhibitor of cholesterol synthesis. Apo B48, the structural protein of the chylomicron particle, is synthesised in abundance so that the release of these particles is dependent on the amount of cholesterol and triglyceride available in the intestine. This paper will discuss cholesterol absorption and synthesis, chylomicron formation, and the effect of postprandial lipoproteins on factors involved in atherosclerosis.
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Jia L, Betters JL, Yu L. Niemann-pick C1-like 1 (NPC1L1) protein in intestinal and hepatic cholesterol transport. Annu Rev Physiol 2011; 73:239-59. [PMID: 20809793 DOI: 10.1146/annurev-physiol-012110-142233] [Citation(s) in RCA: 218] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Increased blood cholesterol is an independent risk factor for atherosclerotic cardiovascular disease. Cholesterol homeostasis in the body is controlled mainly by endogenous synthesis, intestinal absorption, and hepatic excretion. Niemann-Pick C1-Like 1 (NPC1L1) is a polytopic transmembrane protein localized at the apical membrane of enterocytes and the canalicular membrane of hepatocytes. It functions as a sterol transporter to mediate intestinal cholesterol absorption and counter-balances hepatobiliary cholesterol excretion. NPC1L1 is the molecular target of ezetimibe, a potent cholesterol absorption inhibitor that is widely used in treating hypercholesterolemia. Recent findings suggest that NPC1L1 deficiency or ezetimibe treatment also prevents diet-induced hepatic steatosis and obesity in addition to reducing blood cholesterol. Future studies should focus on molecular mechanisms underlying NPC1L1-dependent cholesterol transport and elucidation of how a cholesterol transporter modulates the pathogenesis of metabolic diseases.
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Affiliation(s)
- Lin Jia
- Section on Lipid Sciences, Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1040, USA
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38
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Tang W, Jia L, Ma Y, Xie P, Haywood J, Dawson PA, Li J, Yu L. Ezetimibe restores biliary cholesterol excretion in mice expressing Niemann-Pick C1-Like 1 only in liver. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1811:549-55. [PMID: 21683156 DOI: 10.1016/j.bbalip.2011.05.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 04/28/2011] [Accepted: 05/31/2011] [Indexed: 01/19/2023]
Abstract
Niemann-Pick C1-Like 1 (NPC1L1) is highly expressed in the small intestine across mammalian species and is the target of ezetimibe, a potent cholesterol absorption inhibitor. In humans, NPC1L1 is also expressed in the liver. We found that transgenic overexpression of NPC1L1 in the wild-type mouse liver inhibits biliary cholesterol secretion and raises blood cholesterol, which can be reversed by ezetimibe treatment. Unfortunately, the high expression of endogenous NPC1L1 in the intestine hampered a definitive establishment of the role of hepatic NPC1L1 in cholesterol metabolism and ezetimibe action in the liver because intestinal NPC1L1 dramatically influences cholesterol homeostasis and is a target of ezetimibe. To circumvent this obstacle, we crossed liver-specific NPC1L1 transgenic mice to NPC1L1 knockout (L1-KO) mice and created a mouse line expressing no endogenous NPC1L1, but human NPC1L1 in liver only (L1(LivOnly) mice). Compared to L1-KO mice, L1(LivOnly) mice on a 0.2% cholesterol diet showed significantly increased hepatic and plasma cholesterol, and despite a 90% reduction in biliary cholesterol excretion, their fecal cholesterol excretion remained completely unaltered. Remarkably, 4days of ezetimibe treatment significantly restored biliary cholesterol secretion in L1(LivOnly) mice. These findings demonstrated a direct role of hepatic NPC1L1 in regulating biliary cholesterol excretion and hepatic/blood cholesterol levels, and unequivocally established hepatic NPC1L1 as a target of ezetimibe.
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Affiliation(s)
- Weiqing Tang
- The 5th Clinical Hospital (Beijing Hospital), Peking University, and Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, Ministry of Health, Da Hua Road, Beijing, 100730, China
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39
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Davidson MH. Therapies targeting exogenous cholesterol uptake: new insights and controversies. Curr Atheroscler Rep 2011; 13:95-100. [PMID: 21188557 DOI: 10.1007/s11883-010-0151-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Exogenous cholesterol uptake involves a complex process in the intestines for the absorption of cholesterol and bile acids. This process is regulated by intestinal nuclear transcription factors such as LXR that affect sterol transporters NPC1L1, ABCG5/G8, and ABCG1, and enzymes such as ACAT-2. Plant sterol/stanols, ezetimibe, and bile acid sequestrants have a variety of effects on these various transporters, and new insights into their mechanism(s) of action have provided a plethora of exciting targets for metabolic diseases, dyslipidemia, and atherosclerosis.
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Affiliation(s)
- Michael H Davidson
- Clinical Professor, Director of Preventive Cardiology, The University of Chicago Pritzker School of Medicine, 515 North State Street, Suite 2700, Chicago, IL 60654, USA.
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40
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Ahmed MH, Byrne CD. Potential therapeutic uses for ezetimibe beyond lowering LDL-c to decrease cardiovascular events. Diabetes Obes Metab 2010; 12:958-66. [PMID: 20880342 DOI: 10.1111/j.1463-1326.2010.01261.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ezetimibe is a relatively new drug that inhibits the absorption of dietary cholesterol in the small intestine. It is a low density lipoprotein-cholesterol (LDL-C) lowering medication that acts directly on the intestine by inhibiting Niemann-Pick C1 Like1 (NPC1L1). Recently, results of the ARBITER 6-HALTS trial (Arterial Biology for the Investigation of the Treatment Effects of Reducing Cholesterol 6-HDL and LDL Treatment Strategies) and the ENHANCE trial (Ezetimibe and Simvastatin in Hypercholesterolemia Enhances Atherosclerosis Regression) showed that ezetimibe had no effect on atherosclerosis despite producing a marked decrease in LDL-C. Recent studies show a potential benefit of ezetimibe in treating insulin resistance, non-alcoholic fatty liver disease (NAFLD), gallstones and dyslipidaemia associated with chronic renal failure and organ transplantation. All of these conditions are known to be associated with an increase in risk of cardiovascular disease (CVD) and further studies are needed to assess the potential benefits of ezetimibe in these therapeutics areas.
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Affiliation(s)
- M H Ahmed
- Chemical Pathology Department, Southampton University Hospitals NHS Trust, Southampton, UK
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41
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Ahmed MH, Byrne CD. Ezetimibe as a potential treatment for non-alcoholic fatty liver disease: is the intestine a modulator of hepatic insulin sensitivity and hepatic fat accumulation? Drug Discov Today 2010; 15:590-5. [DOI: 10.1016/j.drudis.2010.06.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 05/30/2010] [Accepted: 06/14/2010] [Indexed: 01/12/2023]
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Betters JL, Yu L. NPC1L1 and cholesterol transport. FEBS Lett 2010; 584:2740-7. [PMID: 20307540 PMCID: PMC2909875 DOI: 10.1016/j.febslet.2010.03.030] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 03/15/2010] [Accepted: 03/16/2010] [Indexed: 12/18/2022]
Abstract
The polytopic transmembrane protein, Niemann-Pick C1-Like 1 (NPC1L1), is enriched in the apical membrane of small intestine absorptive enterocytes where it mediates extracellular sterol transport across the brush border membrane. It is essential for intestinal sterol absorption and is the molecular target of ezetimibe, a potent cholesterol absorption inhibitor that lowers blood cholesterol in humans. NPC1L1 is also highly expressed in human liver. The hepatic function of NPC1L1 may be to limit excessive biliary cholesterol loss. NPC1L1-dependent sterol uptake seems to be a clathrin-mediated endocytic process and is regulated by cellular cholesterol content. Recently, NPC1L1 inhibition has been shown to have beneficial effects on components of the metabolic syndrome, such as obesity, insulin resistance, and fatty liver, in addition to atherosclerosis.
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Affiliation(s)
- Jenna L. Betters
- Department of Pathology Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Liqing Yu
- Department of Pathology Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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43
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Wang HH, Portincasa P, Afdhal NH, Wang DQH. Lith genes and genetic analysis of cholesterol gallstone formation. Gastroenterol Clin North Am 2010; 39:185-207, vii-viii. [PMID: 20478482 DOI: 10.1016/j.gtc.2010.02.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Epidemiologic investigations, clinical observations, and family and twin studies in humans, as well as gallstone prevalence investigations in inbred mouse models, support the concept that cholesterol cholelithiasis could result from a complex interaction of environmental factors and the effects of multiple undetermined genes. Quantitative trait locus (QTL) analysis is a powerful genetic method for identifying primary rate-limiting genetic defects and discriminating them from secondary downstream lithogenic effects caused by mutations of the primary genes, and the subsequent positional cloning of such genes responsible for QTLs, followed by the use of manufactured mouse strains with "knockout" or "knockin" of the genes, could lead to the discovery of lithogenic actions of gallstone (LITH) genes. The combined use of genomic strategies and phenotypic studies in inbred strains of mice has successfully resulted in the identification of many candidate LITH genes. Because there is exceptionally close homology between mouse and human genomes, the orthologous human LITH genes can be identified from the mouse study. The discovery of LITH genes and more fundamental knowledge concerning the genetic determinants and molecular mechanisms underlying the formation of cholesterol gallstones in humans will pave the way for critical diagnostic and prelithogenic preventive measures for this exceptionally prevalent digestive disease.
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Affiliation(s)
- Helen H Wang
- Liver Center and Gastroenterology Division, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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44
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Di Ciaula A, Wang DQH, Wang HH, Bonfrate L, Portincasa P. Targets for current pharmacologic therapy in cholesterol gallstone disease. Gastroenterol Clin North Am 2010; 39:245-64, viii-ix. [PMID: 20478485 PMCID: PMC2915454 DOI: 10.1016/j.gtc.2010.02.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Gallstone disease is a frequent condition throughout the world and, cholesterol stones are the most frequent form in Western countries. The standard treatment of symptomatic gallstone subjects is laparoscopic cholecystectomy. The selection of patients amenable for nonsurgical, medical therapy is of key importance; a careful analysis should consider the natural history of the disease and the overall costs of therapy. Only patients with mild symptoms and small, uncalcified cholesterol gallstones in a functioning gallbladder with a patent cystic duct are considered for oral litholysis by hydrophilic ursodeoxycholic acid, in the hope of achieving cholesterol desaturation of bile and progressive stone dissolution. Recent studies have raised the possibility that cholesterol-lowering agents that inhibit hepatic cholesterol synthesis (statins) or intestinal cholesterol absorption (ezetimibe), or drugs acting on specific nuclear receptors involved in cholesterol and bile acid homeostasis, may offer, alone or in combination, additional medical therapeutic tools for treating cholesterol gallstones. Recent perspectives on medical treatment of cholesterol gallstone disease are discussed in this article.
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Affiliation(s)
- Agostino Di Ciaula
- Division of Internal Medicine, Hospital of Bisceglie, via Bovio 279 - 70052 - Bisceglie (Bari), Italy, +39-80-3363271, +39-80-3363232 (fax)
| | - David Q.-H. Wang
- Liver Center and Gastroenterology Division, Beth Israel Deaconess Medical Center, Department of Medicine, Harvard Medical School and Harvard Digestive Diseases Center, 330 Brookline Avenue, DA 601, Boston, MA 02215, (617) 667-0561, (617) 975-5071 (fax)
| | - Helen H. Wang
- Department of Medicine, Liver Center and Gastroenterology Division, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, DA 601, Boston, MA 02215, (617) 667-5156, (617) 975-5071 (fax)
| | - Leonilde Bonfrate
- Clinica Medica “A. Murri”, Department of Internal and Public Medicine, University of Bari Medical School, Piazza Giulio Cesare 11, Policlinico, 70124 Bari, Italy. +39-80-5478227, +39-80-5478232 (fax)
| | - Piero Portincasa
- Clinica Medica “A. Murri”, Department of Internal Medicine and Public Medicine, University Medical School, Bari, Italy
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Abstract
Obesity is associated with insulin resistance, non-alcoholic fatty liver disease (NAFLD) and gallstones. High fat diets (unsaturated fats) rich in cholesterol have been demonstrated to produce not only gallstones but also NAFLD and insulin resistance. Interestingly, a high incidence of gallstones is being reported in association with insulin resistance and NAFLD. Laparoscopic cholecystectomy is the best definitive therapy for symptomatic gallbladder disease. Ezetimibe is a drug that inhibits the absorption of both dietary and biliary cholesterol in the small intestine. Importantly, ezetimibe showed potential benefit not only in treating and preventing gallstones but also in insulin resistance and NAFLD. Further studies are required before the use of ezetimibe for the treatment of gallstones can be advocated.
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Abstract
Dysregulation of cholesterol balance contributes significantly to atherosclerotic cardiovascular disease (ASCVD), the leading cause of death in the United States. The intestine has the unique capability to act as a gatekeeper for entry of cholesterol into the body, and inhibition of intestinal cholesterol absorption is now widely regarded as an attractive non-statin therapeutic strategy for ASCVD prevention. In this chapter we discuss the current state of knowledge regarding sterol transport across the intestinal brush border membrane. The purpose of this work is to summarize substantial progress made in the last decade in regards to protein-mediated sterol trafficking, and to discuss this in the context of human disease.
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Affiliation(s)
| | - Liqing Yu
- Address correspondence to: Liqing Yu, M.D., Ph.D., Department of Pathology Section on Lipid Sciences, Wake Forest University School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157-1040, Tel: 336-716-0920, Fax: 336-716-6279,
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47
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Lu Y, Feskens EJM, Boer JMA, Müller M. The potential influence of genetic variants in genes along bile acid and bile metabolic pathway on blood cholesterol levels in the population. Atherosclerosis 2009; 210:14-27. [PMID: 19932478 DOI: 10.1016/j.atherosclerosis.2009.10.035] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 10/22/2009] [Accepted: 10/26/2009] [Indexed: 01/10/2023]
Abstract
The liver is currently known to be the major organ to eliminate excess cholesterol from our body. It accomplishes this function in two ways: conversion of cholesterol molecules into bile acids (BAs) and secretion of unesterified cholesterol molecules into bile. BAs are synthesized in the hepatocytes, secreted into bile and delivered to the lumen of the small intestine where they act as detergents to facilitate absorption of fats and fat-soluble vitamins. About 95% of BAs are recovered in the ileum during each cycle of the enterohepatic circulation. Five percent are lost and replaced by newly synthesized BAs, which amounts to approximately 500 mg/day in adult humans. In contrast to the efficiency of the BAs' enterohepatic circulation, 50% of the 1000 mg of cholesterol secreted daily into bile is lost in feces. It is known that rare human mutations in certain genes in bile acid and bile metabolic pathway influence blood cholesterol levels. With the recent success of genome-wide association studies, we are convinced that common genetic variants also play a role in the genetic architecture of plasma lipid traits. In this review, we summarized the current state of knowledge about genetic variations in bile acid and bile metabolic pathway, and assessed their impact on blood cholesterol levels and cholesterol metabolic kinetics in the population.
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Affiliation(s)
- Yingchang Lu
- Division of Human Nutrition, Wageningen University and Research Center, PO Box 8129, 6700 EV Wageningen, The Netherlands.
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48
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Cheng Y, Liu F, Wu J, Zhang Y, Nilsson A, Duan RD. Ezetimibe inhibits expression of acid sphingomyelinase in liver and intestine. Lipids 2009; 44:897-906. [PMID: 19777283 DOI: 10.1007/s11745-009-3343-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Accepted: 09/03/2009] [Indexed: 11/25/2022]
Abstract
Ezetimibe inhibits cholesterol absorption in the intestine. Sphingomyelin has strong interactions with cholesterol. We investigated the effects of ezetimibe on Sphingomyelinase (SMase) expression in intestine and liver. After feeding rats with ezetimibe (5 mg/kg per day) for 14 days, acid SMase activities in the liver and in the proximal part of small intestine were reduced by 34 and 25%, respectively. Alkaline SMase (alk-SMase) was increased in the proximal part of the small intestine. Administration of lower doses of ezetimibe reduced acid SMase only in the liver by 14% (P < 0.05). In cell culture studies, ezetimibe decreased acid SMase activity in Hep G2 and Caco-2 cells dose-dependently. The reductions were more rapid for Hep G2 cells than for Caco-2 cells. Western blot showed that acid SMase protein was decreased in both Hep G2 and Caco-2 cells by 100 microM ezetimibe. The SM content was increased in Hep G2 cells but not Caco-2 cells, and total cholesterol content was increased in both cell lines 24 h after stimulation with 100 microM ezetimibe. Mevastatin, the inhibitor of cholesterol synthesis, induced a mild increase in acid SMase activity in Hep G2 cells but not Caco-2 cells. Following the reduction of acid SMase, ezetimibe at high dose slightly increased alk-SMase activity. In conclusion, the study demonstrates an inhibitory effect of ezetimibe on acid SMase activity and expression in both liver and intestine.
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Affiliation(s)
- Yajun Cheng
- Gastroenterology and Nutrition Lab, BMC, B11, Institution of Clinical Sciences, Lund University, 221 84, Lund, Sweden
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49
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New insights into the molecular mechanisms underlying effects of estrogen on cholesterol gallstone formation. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:1037-47. [PMID: 19589396 DOI: 10.1016/j.bbalip.2009.06.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 06/25/2009] [Accepted: 06/25/2009] [Indexed: 02/07/2023]
Abstract
Epidemiological and clinical studies have found that at all ages women are twice as likely as men to form cholesterol gallstones, and this gender difference begins since puberty and continues through the childbearing years, which highlight the importance of female sex hormones. Estrogen is a crucial hormone in human physiology and regulates a multitude of biological processes. The actions of estrogen have traditionally been ascribed to two closely related classical nuclear hormone receptors, estrogen receptor 1 (ESR1) and ESR2. Recent studies have revealed that the increased risk for cholesterol gallstones in women vs. men is related to differences in how the liver metabolizes cholesterol in response to estrogen. A large number of human and animal studies have proposed that estrogen increases the risk of developing cholesterol gallstones by increasing the hepatic secretion of biliary cholesterol, which, in turn, leads to an increase in cholesterol saturation of bile. Furthermore, it has been identified that hepatic ESR1, but not ESR2, plays a major role in cholesterol gallstone formation in mice in response to high doses of 17beta-estradiol. The mechanisms mediating estrogen's action have become more complicated with the recent identification of a novel estrogen receptor, G protein-coupled receptor 30 (GPR30), a member of the seven-transmembrane G protein-coupled receptor superfamily. In this review, we provide an overview of the evidence for the lithogenic actions of estrogen through ESR1 and discuss the cellular and physiological actions of GPR30 in estrogen-dependent processes and the relationship between GPR30 and classical ESR1 on gallstone formation.
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50
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Brown JM, Yu L. Opposing Gatekeepers of Apical Sterol Transport: Niemann-Pick C1-Like 1 (NPC1L1) and ATP-Binding Cassette Transporters G5 and G8 (ABCG5/ABCG8). IMMUNOLOGY, ENDOCRINE & METABOLIC AGENTS IN MEDICINAL CHEMISTRY 2009; 9:18-29. [PMID: 20174593 PMCID: PMC2824437 DOI: 10.2174/187152209788009797] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cholesterol is essential for the growth and function of all mammalian cells, but abnormally elevated levels of circulating low-density lipoprotein cholesterol (LDL-C) are a major risk factor for the development of atherosclerotic cardiovascular disease (ASCVD). For many years, statin drugs have been used to effectively lower LDL-C, but ASCVD still persists in most of the world. Hence, additional LDL-C lowering is now recommended, and the search for therapeutic strategies that work in synergy with statins has now begun. Intestinal absorption and biliary excretion of cholesterol represent two major pathways and continue to show promise as druggable processes. Importantly, both of these complex physiological pathways are tightly regulated by key proteins located at the apical surface of the small intestine and the liver. One of these proteins, the target of ezetimibe Niemann-Pick C1-Like 1 (NPC1L1), was recently identified to be essential for intestinal cholesterol absorption and protect against excessive biliary sterol loss. In direct opposition of NPC1L1, the heterodimer of ATP-binding cassette transporters G5 and G8 (ABCG5/ABCG8) has been shown to be critical for promoting biliary cholesterol secretion in the liver, and has also been proposed to play a direct role in intestinal disposal of sterols. The purpose of this review is to summarize the current state of knowledge regarding the function of these opposing apical cholesterol transporters, and provide a framework for future studies examining these proteins.
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Affiliation(s)
- J. Mark Brown
- Department of Pathology-Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Liqing Yu
- Department of Pathology-Section on Lipid Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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