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Xu H, Xin Y, Wang J, Liu Z, Cao Y, Li W, Zhou Y, Wang Y, Liu P. The TICE Pathway: Mechanisms and Potential Clinical Applications. Curr Atheroscler Rep 2023; 25:653-662. [PMID: 37736845 DOI: 10.1007/s11883-023-01147-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2023] [Indexed: 09/23/2023]
Abstract
PURPOSE OF REVIEW Transintestinal cholesterol excretion (TICE) is a non-biliary pathway that excretes excess cholesterol from the body through feces. This article focuses on the research progress of the TICE pathway in the last few years, including the discovery process of the TICE pathway, its molecular mechanism, and potential clinical applications. RECENT FINDINGS Cholesterol homeostasis is vital for cardiovascular diseases, stroke, and neurodegenerative diseases. Beyond the cholesterol excretion via hepatobiliary pathway, TICE contributes significantly to reverse cholesterol transport ex vivo and in vivo. Nuclear receptors are ligand-activated transcription factors that regulate cholesterol metabolism. The farnesoid X receptor (FXR) and liver X receptor (LXR) activated, respectively, by oxysterols and bile acids promote intestinal cholesterol secretion through ABCG5/G8. Nutrient regulators and intestinal flora also modulate cholesterol secretion through the TICE pathway. TICE allows direct elimination of plasma cholesterol, which may provide an attractive therapeutic targets. TICE pathway may provide a potential target to stimulate cholesterol elimination and reduce the risk of cardiovascular diseases.
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Affiliation(s)
- Huimin Xu
- Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, Henan University, Henan, China
| | - Yiyang Xin
- Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, Henan University, Henan, China
| | - Jiaxin Wang
- Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, Henan University, Henan, China
| | - Zixin Liu
- Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, Henan University, Henan, China
| | - Yutong Cao
- Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, Henan University, Henan, China
| | - Weiguo Li
- People's Hospital of Hebi, Henan University, Henan, China
| | - Yun Zhou
- Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, Henan University, Henan, China.
| | - Yandong Wang
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China.
| | - Peng Liu
- People's Hospital of Hebi, Henan University, Henan, China.
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2
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Zhou M, Kong B, Zhang X, Xiao K, Lu J, Li W, Li M, Li Z, Ji W, Hou J, Xu T. A proximity labeling strategy enables proteomic analysis of inter-organelle membrane contacts. iScience 2023; 26:107159. [PMID: 37485370 PMCID: PMC10362359 DOI: 10.1016/j.isci.2023.107159] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/03/2023] [Accepted: 06/13/2023] [Indexed: 07/25/2023] Open
Abstract
Inter-organelle membrane contacts are highly dynamic and act as central hubs for many biological processes, but the protein compositions remain largely unknown due to the lack of efficient tools. Here, we developed BiFCPL to analyze the contact proteome in living cells by a bimolecular fluorescence complementation (BiFC)-based proximity labeling (PL) strategy. BiFCPL was applied to study mitochondria-endoplasmic reticulum contacts (MERCs) and mitochondria-lipid droplet (LD) contacts. We identified 403 highly confident MERC proteins, including many transiently resident proteins and potential tethers. Moreover, we demonstrated that mitochondria-LD contacts are sensitive to nutrient status. A comparative proteomic analysis revealed that 60 proteins are up- or downregulated at contact sites under metabolic challenge. We verified that SQLE, an enzyme for cholesterol synthesis, accumulates at mitochondria-LD contact sites probably to utilize local ATP for cholesterol synthesis. This work provides an efficient method to identify key proteins at inter-organelle membrane contacts in living cells.
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Affiliation(s)
- Maoge Zhou
- Guangzhou Laboratory, Guangzhou, Guangdong 510005, China
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Bingjie Kong
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiang Zhang
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Ke Xiao
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jing Lu
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Weixing Li
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Min Li
- Guangzhou Laboratory, Guangzhou, Guangdong 510005, China
| | - Zonghong Li
- Guangzhou Laboratory, Guangzhou, Guangdong 510005, China
| | - Wei Ji
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junjie Hou
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Tao Xu
- Guangzhou Laboratory, Guangzhou, Guangdong 510005, China
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
- School of Biomedical Engineering, Guangzhou Medical University, Guangzhou, Guangdong 511436, China
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3
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The effect of nutrient deprivation on proteasome activity in 4-week-old mice and 24-week-old mice. J Nutr Biochem 2022; 105:108993. [DOI: 10.1016/j.jnutbio.2022.108993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 10/20/2021] [Accepted: 02/03/2022] [Indexed: 11/21/2022]
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Abstract
PURPOSE OF REVIEW The transintestinal cholesterol efflux (TICE) pathway is the second described route for plasma cholesterol fecal elimination. This article summarizes recent TICE research progresses, involving TICE inducers, molecular determinants of this pathway, and its role in lipoprotein metabolism. RECENT FINDINGS TICE is an active pathway in mice, rats, and humans. Kinetic measurements showed that under basal conditions, the relative contribution of TICE in fecal elimination of plasma cholesterol is quantitatively less important than the hepatobiliary pathway. However, the amplitude of TICE can be induced by numerous nutritional factors and pharmacological drugs. More importantly, by contrast with the stimulation of biliary cholesterol excretion that is associated with an increased risk of gallstone formation, TICE appears as a safer therapeutical target. Finally, several independent studies have demonstrated that TICE is actively contributing to the anti-atherogenic reverse cholesterol pathway reinforcing the interest to better understand its mode of action. The discovery of TICE and the understanding of its mode of action open new therapeutical perspectives for patients at high risk of cardiovascular diseases.
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Giroud S, Chery I, Arrivé M, Prost M, Zumsteg J, Heintz D, Evans AL, Gauquelin-Koch G, Arnemo JM, Swenson JE, Lefai E, Bertile F, Simon C, Blanc S. Hibernating brown bears are protected against atherogenic dyslipidemia. Sci Rep 2021; 11:18723. [PMID: 34548543 PMCID: PMC8455566 DOI: 10.1038/s41598-021-98085-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 08/23/2021] [Indexed: 11/16/2022] Open
Abstract
To investigate mechanisms by which hibernators avoid atherogenic hyperlipidemia during hibernation, we assessed lipoprotein and cholesterol metabolisms of free-ranging Scandinavian brown bears (Ursus arctos). In winter- and summer-captured bears, we measured lipoprotein sizes and sub-classes, triglyceride-related plasma-enzyme activities, and muscle lipid composition along with plasma-levels of antioxidant capacities and inflammatory markers. Although hibernating bears increased nearly all lipid levels, a 36%-higher cholesteryl-ester transfer-protein activity allowed to stabilize lipid composition of high-density lipoproteins (HDL). Levels of inflammatory metabolites, i.e., 7-ketocholesterol and 11ß-prostaglandin F2α, declined in winter and correlated inversely with cardioprotective HDL2b-proportions and HDL-sizes that increased during hibernation. Lower muscle-cholesterol concentrations and lecithin-cholesterol acyltransferase activity in winter suggest that hibernating bears tightly controlled peripheral-cholesterol synthesis and/or release. Finally, greater plasma-antioxidant capacities prevented excessive lipid-specific oxidative damages in plasma and muscles of hibernating bears. Hence, the brown bear manages large lipid fluxes during hibernation, without developing adverse atherogenic effects that occur in humans and non-hibernators.
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Affiliation(s)
- Sylvain Giroud
- Research Institute of Wildlife Ecology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine, Vienna, Savoyenstraße 1, 1160, Vienna, Austria.
| | - Isabelle Chery
- University of Strasbourg, 4 rue Blaise Pascal, 67081, Strasbourg, France.,CNRS, UMR7178, Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du Loess, 67087, Strasbourg, France
| | - Mathilde Arrivé
- University of Strasbourg, 4 rue Blaise Pascal, 67081, Strasbourg, France.,CNRS, UMR7178, Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du Loess, 67087, Strasbourg, France
| | | | - Julie Zumsteg
- Plant Imaging & Mass Spectrometry (PIMS), Institute of Plant Molecular Biology, CNRS, University of Strasbourg, 12 rue du Général Zimmer, 67084, Strasbourg, France
| | - Dimitri Heintz
- Plant Imaging & Mass Spectrometry (PIMS), Institute of Plant Molecular Biology, CNRS, University of Strasbourg, 12 rue du Général Zimmer, 67084, Strasbourg, France
| | - Alina L Evans
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, 2480, Koppang, Norway
| | | | - Jon M Arnemo
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, 2480, Koppang, Norway.,Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, 90183, Umeå, Sweden
| | - Jon E Swenson
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, 1432, Ås, Norway
| | - Etienne Lefai
- University of Auvergne, INRAE, UNH UMR1019, 63122, Saint-Genès Champanelle, France
| | - Fabrice Bertile
- University of Strasbourg, 4 rue Blaise Pascal, 67081, Strasbourg, France.,CNRS, UMR7178, Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du Loess, 67087, Strasbourg, France
| | - Chantal Simon
- CARMEN, INSERM U1060/University of Lyon / INRA U1235, Oullins, France
| | - Stéphane Blanc
- University of Strasbourg, 4 rue Blaise Pascal, 67081, Strasbourg, France.,CNRS, UMR7178, Institut Pluridisciplinaire Hubert Curien (IPHC), 23 rue du Loess, 67087, Strasbourg, France
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6
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Nabi G, Li Y, McLaughlin RW, Mei Z, Wang K, Hao Y, Zheng J, Wang D. Immune Responses of the Critically Endangered Yangtze Finless Porpoises ( Neophocaena asiaeorientalis ssp. asiaeorientalis) to Escalating Anthropogenic Stressors in the Wild and Seminatural Environments. Front Physiol 2020; 10:1594. [PMID: 32116734 PMCID: PMC7010939 DOI: 10.3389/fphys.2019.01594] [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: 08/29/2019] [Accepted: 12/19/2019] [Indexed: 01/03/2023] Open
Abstract
Increasing anthropogenic stressors are potential threats to biodiversity conservation and management of Yangtze finless porpoises (YFPs). The objective of this study was to indirectly compare the habitat quality of a natural reserve, Poyang Lake and a seminatural reserve, the Tian-E-Zhou Oxbow (TZO) in terms of anthropogenic stressors by investigating different stress and immunological parameters in the blood of YFPs. Samples from a total of 74 YFPs from the TZO (n = 43) and Poyang Lake (n = 31) were collected and analyzed. The animals were divided into ontogenetic groups: male calf, female calf, juvenile female, juvenile male, and adult male, and reproductive groups: pregnant female, lactating female, and pregnant plus lactating. The blood from all the animals was analyzed for general stress (HSP14, SOD1, TXN, and FTL), metabolic stress (ACAT2 and THRA), and immunity-related genes (IL12p40, IFNγ, TNFα; IL1α, IL1ra, COX2, CRPL, IL4, and IL8) using qPCR. YFPs living in Poyang Lake showed an increased relative expression pattern for IFNγ, IL1ra, IL4, ACAT2, and CRPL across all the ontogenetic groups with significantly higher expression in adult males. In contrast, YFPs living in the TZO showed a significantly higher expression in 13 of 15 genes analyzed in the male calf group. Across the reproductive states for porpoises living in Poyang Lake, eight of the 15 genes in the pregnant female and three of the 15 genes in the pregnant plus lactating group had a significantly higher expression level. However, in YFPs living in the TZO, eight of the 15 genes showed significantly higher expression in the pregnant and lactating groups. There was significantly a higher expression of most of the genes in porpoises living in the TZO compared to the age-matched groups from porpoises living in Poyang Lake. The exception was the pregnant female group. The higher relative expression of stress and immune genes in the TZO porpoise population compared to porpoises living in Poyang Lake suggests the effects of worsening habitat quality, possibly indicating water pollution and lack of feeding resources.
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Affiliation(s)
- Ghulam Nabi
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China.,Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Science, Hebei Normal University, Shijiazhuang, China
| | - Ying Li
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | | | - Zhigang Mei
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Kexiong Wang
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Yujiang Hao
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jinsong Zheng
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Ding Wang
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
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7
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Yokota SI, Ando M, Nakamura K, Shibata S. Combined effect of shortened photoperiod and low crude protein diet on liver triglyceride accumulation and lipid-related gene expression in quail. Livest Sci 2018. [DOI: 10.1016/j.livsci.2018.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Ahn WG, Jung JS, Song DK. Lipidomic analysis of plasma lipids composition changes in septic mice. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2018; 22:399-408. [PMID: 29962854 PMCID: PMC6019871 DOI: 10.4196/kjpp.2018.22.4.399] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 03/30/2018] [Accepted: 04/06/2018] [Indexed: 01/16/2023]
Abstract
A lipidomic study on extensive plasma lipids in bacterial peritonitis (cecal ligation and puncture, CLP)-induced sepsis in mice was done at 24 h post-CLP. The effects of administration of lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA), compounds known to have beneficial effects in CLP, on the sepsis-induced plasma lipid changes were also examined. Among the 147 plasma lipid species from 13 lipid subgroups (fatty acid [FA], LPA, LPC, lysophosphatidylethanolamine [LPE], phosphatidic acid [PA], phosphatidylcholine [PC], phosphatidylethanolamine [PE], phosphatidylinositol [PI], monoacylglyceride [MG], diacylglyceride [DG], triacylglyceride [TG], sphingomyelin [SM], and ceramide [Cer]) analyzed in this study, 40 and 70 species were increased, and decreased, respectively, in the CLP mice. Treatments with LPC and LPA affected 14 species from 7 subgroups, and 25 species from 9 subgroups, respectively. These results could contribute to finding the much needed reliable biomarkers of sepsis.
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Affiliation(s)
- Won-Gyun Ahn
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
| | - Jun-Sub Jung
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
| | - Dong-Keun Song
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
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9
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Nabi G, Hao Y, Zeng X, Jinsong Z, McLaughlin RW, Wang D. Hematologic and biochemical differences between two free ranging Yangtze finless porpoise populations: The implications of habitat. PLoS One 2017; 12:e0188570. [PMID: 29190288 PMCID: PMC5708617 DOI: 10.1371/journal.pone.0188570] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/09/2017] [Indexed: 11/19/2022] Open
Abstract
The goals of this study were to compare the serum chemistry and hematology values of wild and semi-natural free-ranging Yangtze Finless Porpoises (Neophocaena asiaeorientalis ssp. asiaeorientalis) populations and to ascertain how these values change with the different environmental condition. For this study, samples were collected from 81 YFPs, 35 living in the wild and 46 living in a semi-natural reserve. Each population was divided into 8 life history categories; Male Calf, Female Calf, Juvenile Male, Juvenile Female, Adult Male, Pregnant, Lactating and Pregnant plus Lactating. Statistically significant differences in the various parameters were observed in the same life history categories for both populations. Generally, Lipid Profile, Hepatic Enzymes, Creatine Kinase, Red Blood Cells, Hemoglobin, Hematocrit and Neutrophils were significantly higher in the Tian-E-Zhou Oxbow population while, Creatinine, Phosphate, Lactate Dehydrogenase, Bilirubin and Lymphocytes were significantly higher in the Poyang Lake YFPs. Across the groups in the Tian-E-Zhou Oxbow population, a significant decrease in serum Albumin, Alkaline Phosphatase and Calcium, while a significant increase in the Neutrophils and Platelets was observed. Similarly, in the Poyang Lake, Alkaline Phosphatase levels in the Female Calves group, High Density Lipoprotein Cholesterol in Lactating group, basophil counts in Pregnant plus Lactating group, lymphocytes counts in Juvenile Females group and Globulin and Total Protein levels in Pregnant group were significantly higher. This study in health assessments can help us to understand the effect of sex, age, reproductive status and environmental conditions on the well-being of Yangtze Finless Porpoises.
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Affiliation(s)
- Ghulam Nabi
- Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, Hubei, PR China
- University of the Chinese Academy of Sciences, Shijingshan District, Beijing, PR China
| | - Yujiang Hao
- Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, Hubei, PR China
- * E-mail: (DW); (YH)
| | - Xianyuan Zeng
- Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, Hubei, PR China
- University of the Chinese Academy of Sciences, Shijingshan District, Beijing, PR China
| | - Zheng Jinsong
- Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, Hubei, PR China
| | - Richard W. McLaughlin
- General Studies, Gateway Technical College, Kenosha, Wisconsin, United States of America
| | - Ding Wang
- Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, Hubei, PR China
- * E-mail: (DW); (YH)
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10
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Paalvast Y, Gerding A, Wang Y, Bloks VW, van Dijk TH, Havinga R, Willems van Dijk K, Rensen PCN, Bakker BM, Kuivenhoven JA, Groen AK. Male apoE*3-Leiden.CETP mice on high-fat high-cholesterol diet exhibit a biphasic dyslipidemic response, mimicking the changes in plasma lipids observed through life in men. Physiol Rep 2017; 5:e13376. [PMID: 29038350 PMCID: PMC5641925 DOI: 10.14814/phy2.13376] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 07/08/2017] [Accepted: 07/10/2017] [Indexed: 12/18/2022] Open
Abstract
Physiological adaptations resulting in the development of the metabolic syndrome in man occur over a time span of several decades. This combined with the prohibitive financial cost and ethical concerns to measure key metabolic parameters repeatedly in subjects for the major part of their life span makes that comprehensive longitudinal human data sets are virtually nonexistent. While experimental mice are often used, little is known whether this species is in fact an adequate model to better understand the mechanisms that drive the metabolic syndrome in man. We took up the challenge to study the response of male apoE*3-Leiden.CETP mice (with a humanized lipid profile) to a high-fat high-cholesterol diet for 6 months. Study parameters include body weight, food intake, plasma and liver lipids, hepatic transcriptome, VLDL - triglyceride production and importantly the use of stable isotopes to measure hepatic de novo lipogenesis, gluconeogenesis, and biliary/fecal sterol secretion to assess metabolic fluxes. The key observations include (1) high inter-individual variation; (2) a largely unaffected hepatic transcriptome at 2, 3, and 6 months; (3) a biphasic response curve of the main metabolic features over time; and (4) maximum insulin resistance preceding dyslipidemia. The biphasic response in plasma triglyceride and total cholesterol appears to mimic that of men in cross-sectional studies. Combined, these observations suggest that studies such as these can help to delineate the causes of metabolic derangements in patients suffering from metabolic syndrome.
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Affiliation(s)
- Yared Paalvast
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Albert Gerding
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Yanan Wang
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
- Department Medicine, Division Endocrinology, Leiden University Medical Center, Leiden, The Netherlands
| | - Vincent W Bloks
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Theo H van Dijk
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Rick Havinga
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Ko Willems van Dijk
- Department Medicine, Division Endocrinology, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine Leiden University Medical Center, Leiden, The Netherlands
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Patrick C N Rensen
- Department Medicine, Division Endocrinology, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine Leiden University Medical Center, Leiden, The Netherlands
| | - Barbara M Bakker
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan Albert Kuivenhoven
- Department of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands
| | - Albert K Groen
- Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
- Department of Vascular Medicine, Amsterdam Medical Center, Amsterdam, The Netherlands
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11
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Feng L, Yuen YL, Xu J, Liu X, Chan MYC, Wang K, Fong WP, Cheung WT, Lee SST. Identification and characterization of a novel PPARα-regulated and 7α-hydroxyl bile acid-preferring cytosolic sulfotransferase mL-STL (Sult2a8). J Lipid Res 2017; 58:1114-1131. [PMID: 28442498 DOI: 10.1194/jlr.m074302] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 04/19/2017] [Indexed: 12/25/2022] Open
Abstract
PPARα has been known to play a pivotal role in orchestrating lipid, glucose, and amino acid metabolism via transcriptional regulation of its target gene expression during energy deprivation. Recent evidence has also suggested that PPARα is involved in bile acid metabolism, but how PPARα modulates the homeostasis of bile acids during fasting is still not clear. In a mechanistic study aiming to dissect the spectrum of PPARα target genes involved in metabolic response to fasting, we identified a novel mouse gene (herein named mL-STL for mouse liver-sulfotransferase-like) that shared extensive homology with the Sult2a subfamily of a superfamily of cytosolic sulfotransferases, implying its potential function in sulfonation. The mL-STL gene expressed predominantly in liver in fed state, but PPARα was required to sustain its expression during fasting, suggesting a critical role of PPARα in regulating the mL-STL-mediated sulfonation during fasting. Functional studies using recombinant His-tagged mL-STL protein revealed its narrow sulfonating activities toward 7α-hydroxyl primary bile acids, including cholic acid, chenodeoxycholic acid, and α-muricholic acid, and thus suggesting that mL-STL may be the major hepatic bile acid sulfonating enzyme in mice. Together, these studies identified a novel PPARα-dependent gene and uncovered a new role of PPARα as being an essential regulator in bile acid biotransformation via sulfonation during fasting.
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Affiliation(s)
- Lu Feng
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Yee-Lok Yuen
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Jian Xu
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Xing Liu
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Martin Yan-Chun Chan
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Kai Wang
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Wing-Ping Fong
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Wing-Tai Cheung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Susanna Sau-Tuen Lee
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
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12
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Abstract
Extended bouts of fasting are ingrained in the ecology of many organisms, characterizing aspects of reproduction, development, hibernation, estivation, migration, and infrequent feeding habits. The challenge of long fasting episodes is the need to maintain physiological homeostasis while relying solely on endogenous resources. To meet that challenge, animals utilize an integrated repertoire of behavioral, physiological, and biochemical responses that reduce metabolic rates, maintain tissue structure and function, and thus enhance survival. We have synthesized in this review the integrative physiological, morphological, and biochemical responses, and their stages, that characterize natural fasting bouts. Underlying the capacity to survive extended fasts are behaviors and mechanisms that reduce metabolic expenditure and shift the dependency to lipid utilization. Hormonal regulation and immune capacity are altered by fasting; hormones that trigger digestion, elevate metabolism, and support immune performance become depressed, whereas hormones that enhance the utilization of endogenous substrates are elevated. The negative energy budget that accompanies fasting leads to the loss of body mass as fat stores are depleted and tissues undergo atrophy (i.e., loss of mass). Absolute rates of body mass loss scale allometrically among vertebrates. Tissues and organs vary in the degree of atrophy and downregulation of function, depending on the degree to which they are used during the fast. Fasting affects the population dynamics and activities of the gut microbiota, an interplay that impacts the host's fasting biology. Fasting-induced gene expression programs underlie the broad spectrum of integrated physiological mechanisms responsible for an animal's ability to survive long episodes of natural fasting.
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Affiliation(s)
- Stephen M Secor
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA
| | - Hannah V Carey
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin, USA
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Yokota SI, Nakamura K, Ando M, Kamei H, Hakuno F, Takahashi SI, Shibata S. Acetylcholinesterase (AChE) inhibition aggravates fasting-induced triglyceride accumulation in the mouse liver. FEBS Open Bio 2014; 4:905-14. [PMID: 25383314 PMCID: PMC4223152 DOI: 10.1016/j.fob.2014.10.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 10/13/2014] [Accepted: 10/16/2014] [Indexed: 12/11/2022] Open
Abstract
Although fasting induces hepatic triglyceride (TG) accumulation in both rodents and humans, little is known about the underlying mechanism. Because parasympathetic nervous system activity tends to attenuate the secretion of very-low-density-lipoprotein-triglyceride (VLDL-TG) and increase TG stores in the liver, and serum cholinesterase activity is elevated in fatty liver disease, the inhibition of the parasympathetic neurotransmitter acetylcholinesterase (AChE) may have some influence on hepatic lipid metabolism. To assess the influence of AChE inhibition on lipid metabolism, the effect of physostigmine, an AChE inhibitor, on fasting-induced increase in liver TG was investigated in mice. In comparison with ad libitum-fed mice, 30 h fasting increased liver TG accumulation accompanied by a downregulation of sterol regulatory element-binding protein 1 (SREBP-1) and liver-fatty acid binding-protein (L-FABP). Physostigmine promoted the 30 h fasting-induced increase in liver TG levels in a dose-dependent manner, accompanied by a significant fall in plasma insulin levels, without a fall in plasma TG. Furthermore, physostigmine significantly attenuated the fasting-induced decrease of both mRNA and protein levels of SREBP-1 and L-FABP, and increased IRS-2 protein levels in the liver. The muscarinic receptor antagonist atropine blocked these effects of physostigmine on liver TG, serum insulin, and hepatic protein levels of SREBP-1 and L-FABP. These results demonstrate that AChE inhibition facilitated fasting-induced TG accumulation with up regulation of the hepatic L-FABP and SREBP-1 in mice, at least in part via the activation of muscarinic acetylcholine receptors. Our studies highlight the crucial role of parasympathetic regulation in fasting-induced TG accumulation, and may be an important source of information on the mechanism of hepatic disorders of lipid metabolism.
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Key Words
- ACC, acetyl coenzyme-A carboxylase
- ACh, acetylcholine
- AChE, acetylcholinesterase
- CPT-1, carnitine palmitoyltransferase 1
- FA, fatty acid(s)
- FAS, fatty acid synthase
- Fatty liver
- IRS-2, insulin receptor substrate
- L-FABP, liver fatty acid-binding protein
- Lipogenesis
- Lipolysis
- Metabolic syndrome
- PEPCK, phosphoenolpyruvate carboxykinase
- PGC-1α, peroxisome proliferator activated receptor gamma coactivator 1-alpha
- PPAR-α, peroxisome proliferator activated receptor alpha
- Parasympathetic nerve
- SREBP, sterol regulatory element binding proteins
- TG, triglyceride(s)
- Triglyceride
- VLDL, very low-density lipoprotein(s)
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Affiliation(s)
- Shin-Ichi Yokota
- Department of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan ; Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, Tokyo, Japan
| | - Kaai Nakamura
- Department of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Midori Ando
- Department of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Hiroyasu Kamei
- Department of Animal Sciences and Applied Biological Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Fumihiko Hakuno
- Department of Animal Sciences and Applied Biological Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Shin-Ichiro Takahashi
- Department of Animal Sciences and Applied Biological Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Shigenobu Shibata
- Department of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
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Blanchard C, Moreau F, Cariou B, Le May C. [Trans-intestinal cholesterol excretion (TICE): a new route for cholesterol excretion]. Med Sci (Paris) 2014; 30:896-901. [PMID: 25311025 DOI: 10.1051/medsci/20143010017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The small intestine plays a crucial role in dietary and biliary cholesterol absorption, as well as its lymphatic secretion as chylomicrons (lipoprotein exogenous way). Recently, a new metabolic pathway called TICE (trans-intestinal excretion of cholesterol) that plays a central role in cholesterol metabolism has emerged. TICE is an inducible way, complementary to the hepatobiliary pathway, allowing the elimination of the plasma cholesterol directly into the intestine lumen through the enterocytes. This pathway is poorly characterized but several molecular actors of TICE have been recently identified. Although it is a matter of debate, two independent studies suggest that TICE is involved in the anti-atherogenic reverse cholesterol transport pathway. Thus, TICE is an innovative drug target to reduce -cardiovascular diseases.
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Affiliation(s)
- Claire Blanchard
- IRS-UN, institut du thorax, unité Inserm UMR 1087/CNRS UMR 6291, 8, quai Moncousu, 44007 Nantes Cedex 1, France
| | - François Moreau
- IRS-UN, institut du thorax, unité Inserm UMR 1087/CNRS UMR 6291, 8, quai Moncousu, 44007 Nantes Cedex 1, France
| | - Bertrand Cariou
- IRS-UN, institut du thorax, unité Inserm UMR 1087/CNRS UMR 6291, 8, quai Moncousu, 44007 Nantes Cedex 1, France
| | - Cédric Le May
- IRS-UN, institut du thorax, unité Inserm UMR 1087/CNRS UMR 6291, 8, quai Moncousu, 44007 Nantes Cedex 1, France
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15
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Regnault C, Worms IAM, Oger-Desfeux C, MelodeLima C, Veyrenc S, Bayle ML, Combourieu B, Bonin A, Renaud J, Raveton M, Reynaud S. Impaired liver function in Xenopus tropicalis exposed to benzo[a]pyrene: transcriptomic and metabolic evidence. BMC Genomics 2014; 15:666. [PMID: 25103525 PMCID: PMC4141109 DOI: 10.1186/1471-2164-15-666] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 07/30/2014] [Indexed: 12/20/2022] Open
Abstract
Background Despite numerous studies suggesting that amphibians are highly sensitive to cumulative anthropogenic stresses, the role pollutants play in the decline of amphibian populations remains unclear. Amongst the most common aquatic contaminants, polycyclic aromatic hydrocarbons (PAHs) have been shown to induce several adverse effects on amphibian species in the larval stages. Conversely, adults exposed to high concentrations of the ubiquitous PAH, benzo[a]pyrene (BaP), tolerate the compound thanks to their highly efficient hepatic detoxification mechanisms. Due to this apparent lack of toxic effect on adults, no studies have examined in depth the potential toxicological impact of PAH on the physiology of adult amphibian livers. This study sheds light on the hepatic responses of Xenopus tropicalis when exposed to high environmentally relevant concentrations of BaP, by combining a high throughput transcriptomic approach (mRNA deep sequencing) and a characterization of cellular and physiological modifications to the amphibian liver. Results Transcriptomic changes observed in BaP-exposed Xenopus were further characterized using a time-dependent enrichment analysis, which revealed the pollutant-dependent gene regulation of important biochemical pathways, such as cholesterol biosynthesis, insulin signaling, adipocytokines signaling, glycolysis/gluconeogenesis and MAPK signaling. These results were substantiated at the physiological level with the detection of a pronounced metabolic disorder resulting in a possible insulin resistance-like syndrome phenotype. Hepatotoxicity induced by lipid and cholesterol metabolism impairments was clearly identified in BaP-exposed individuals. Conclusions Our data suggested that BaP may disrupt overall liver physiology, and carbohydrate and cholesterol metabolism in particular, even after short-term exposure. These results are further discussed in terms of how this deregulation of liver physiology can lead to general metabolic impairment in amphibians chronically exposed to contaminants, thereby illustrating the role xenobiotics might play in the global decline in amphibian populations. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-666) contains supplementary material, which is available to authorized users.
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16
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A single daily meal at the beginning of the active or inactive period inhibits food deprivation-induced fatty liver in mice. Nutr Res 2014; 34:613-22. [PMID: 25150120 DOI: 10.1016/j.nutres.2014.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 06/02/2014] [Accepted: 06/06/2014] [Indexed: 12/11/2022]
Abstract
Food deprivation (FD) induces hepatic steatosis in both rodents and humans. Although body composition, age, and sex influence hepatic triglyceride (TG) levels after FD, whether feeding patterns affect FD-induced liver TG increases is unknown. We hypothesized that restricted feeding (RF) of 1 meal per day during the active or inactive period (especially the inactive period) augments FD-induced elevation of liver TGs because RF in the inactive period impairs the circadian rhythm. Triglyceride levels and the expression of genes related to TG metabolism in the liver were examined by a bioassay and real-time reverse transcription-polymerase chain reaction, respectively. In the first experiment, when compared to nonfasted mice, mice that fasted for 24 hours showed a 1.5-fold (FD starting during the inactive period) to 3-fold (FD started during the active period) increase in liver TG levels. This experiment showed that TG levels depend upon the starting time of FD. In the second experiment, mice were given free access to food for 3 hours at the beginning of either the inactive ("supper-only") or the active ("breakfast-only") period for 2 weeks. Restricted feeding inhibited the FD-induced increases in liver and serum TG levels, serum free fatty acids, and the expression of genes related to fatty acid uptake in the liver, including fatty acid transport protein 1 (Fatp1) and 4 (Fatp4). Unexpectedly, compared to free feeding, RF during the active or inactive period resulted in resistance to FD-induced fatty liver. This is the first study to demonstrate that feeding patterns affect FD-induced TG accumulation in the mouse liver.
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Osada J. The use of transcriptomics to unveil the role of nutrients in Mammalian liver. ISRN NUTRITION 2013; 2013:403792. [PMID: 24967258 PMCID: PMC4045299 DOI: 10.5402/2013/403792] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Accepted: 08/04/2013] [Indexed: 01/03/2023]
Abstract
Liver is the organ primarily responding to diet, and it is crucial in determining plasma carbohydrate, protein, and lipid levels. In addition, it is mainly responsible for transformation of xenobiotics. For these reasons, it has been a target of transcriptomic analyses. In this review, we have covered the works dealing with the response of mammalian liver to different nutritional stimuli such as fasting/feeding, caloric restriction, dietary carbohydrate, cholesterol, fat, protein, bile acid, salt, vitamin, and oligoelement contents. Quality of fats or proteins has been equally addressed, and has the influence of minor dietary components. Other compounds, not purely nutritional as those represented by alcohol and food additives, have been included due to their relevance in processed food. The influence has been studied not only on mRNA but also on miRNA. The wide scope of the technology clearly reflects that any simple intervention has profound changes in many metabolic parameters and that there is a synergy in response when more compounds are included in the intervention. Standardized arrays to systematically test the same genes in all studies and analyzing data to establish patterns of response are required, particularly for RNA sequencing. Moreover, RNA is a valuable, easy-screening ally but always requires further confirmation.
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Affiliation(s)
- Jesús Osada
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Veterinaria, Instituto de Investigación Sanitaria de Aragón, Universidad de Zaragoza, 50013 Zaragoza, Spain ; CIBER de Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 28029 Madrid, Spain
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18
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Sokolović A, van Roomen CPAA, Ottenhoff R, Scheij S, Hiralall JK, Claessen N, Aten J, Oude Elferink RPJ, Groen AK, Sokolović M. Fasting reduces liver fibrosis in a mouse model for chronic cholangiopathies. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1482-91. [PMID: 23707514 DOI: 10.1016/j.bbadis.2013.05.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 05/06/2013] [Accepted: 05/14/2013] [Indexed: 01/18/2023]
Abstract
Chronic cholangiopathies often lead to fibrosis, as a result of a perpetuated wound healing response, characterized by increased inflammation and excessive deposition of proteins of the extracellular matrix. Our previous studies have shown that food deprivation suppresses the immune response, which led us to postulate its beneficial effects on pathology in liver fibrosis driven by portal inflammation. We investigated the consequences of fasting on liver fibrosis in Abcb4(-/-) mice that spontaneously develop it due to a lack of phospholipids in bile. The effect of up to 48h of food deprivation was studied by gene expression profiling, (immuno)histochemistry, and biochemical assessments of biliary output, and hepatic and plasma lipid composition. In contrast to increased biliary output in the wild type counterparts, bile composition in Abcb4(-/-) mice remained unchanged with fasting and did not influence the attenuation of fibrosis. Markers of inflammation, however, dramatically decreased in livers of Abcb4(-/-) mice already after 12h of fasting. Reduced presence of activated hepatic stellate cells and actively increased tissue remodeling further propelled a decrease in parenchymal fibrosis in fasting. This study is the first to show that food deprivation positively influences liver pathology in a fibrotic mouse model for chronic cholangiopathies, opening a door for new strategies to improve liver regeneration in chronic disease.
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19
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Gebhardt R, Coffer PJ. Hepatic autophagy is differentially regulated in periportal and pericentral zones - a general mechanism relevant for other tissues? Cell Commun Signal 2013; 11:21. [PMID: 23531205 PMCID: PMC3623826 DOI: 10.1186/1478-811x-11-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 03/11/2013] [Indexed: 02/08/2023] Open
Abstract
Background Liver zonation, the fact that metabolic pathways are spatially separated along the liver sinusoids, is fundamental for proper functioning of this organ. For example, glutamine synthesis from glutamate and ammonia is localized pericentrally in only 7% of the hepatocytes concentrically arranged around the central veins. Recently, we found that FOXO transcription factors lead to upregulation of glutamine synthetase expression inducing autophagy via increasing glutamine production. Since in liver this mechanism can only be functioning in the pericentral zone it remains unclear how autophagy might be regulated in the rest of liver parenchyma. Presentation of the hypothesis We hypothesize that the regulation of autophagy by glutamine in liver is zonated. In the periportal zone, autophagy is inhibited by low intracellular glutamine but high essential amino acids, while in the pericentral zone it is stimulated by high intracellular glutamine. This zonation may be controlled by the Wnt and Hedgehog signalling pathways through reciprocal influence on the expression of amino acid transporters and metabolic enzymes in the different zones of the parenchyma. Testing the hypothesis The hypothesis can be tested in transgenic mice with conditional hepatocyte-specific modulation of Wnt and Hedgehog signalling. Isolated periportal and pericentral hepatocyte populations allow for determining the different activities of autophagy and its regulating mechanisms in different zones of the parenchyma. Implications of the hypothesis Zonation of the regulation of autophagy may allow adapting the extent of the proteolytic breakdown of proteins and organelles to different physiological needs in different zones of liver parenchyma. In this manner metabolic functions can be supported in one zone, for example maintenance of blood glucose levels during starvation which is a periportal issue, while simultaneously preventing cytotoxic events in the opposite zone. Likewise, lipid metabolism can be differentially influenced by uncoupling periportal lipophagy from pericentral breakdown of peroxisomes. Further implications concern the shaping of morphogen gradients along the sinusoidal axis by autophagy, and the different contribution of autophagy to the development of various different liver pathologies. The proposed dependence of the dual glutamine-dependent regulatory mechanisms of autophagy on inverse gradients of Wnt and hedgehog signalling may be relevant for other tissues in which GS is heterogeneously expressed.
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Affiliation(s)
- Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany.
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20
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The Lipid Transfer Protein StarD7: Structure, Function, and Regulation. Int J Mol Sci 2013; 14:6170-86. [PMID: 23507753 PMCID: PMC3634439 DOI: 10.3390/ijms14036170] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 02/17/2013] [Accepted: 02/22/2013] [Indexed: 02/06/2023] Open
Abstract
The steroidogenic acute regulatory (StAR) protein-related lipid transfer (START) domain proteins constitute a family of evolutionarily conserved and widely expressed proteins that have been implicated in lipid transport, metabolism, and signaling. The 15 well-characterized mammalian START domain-containing proteins are grouped into six subfamilies. The START domain containing 7 mRNA encodes StarD7, a member of the StarD2/phosphatidylcholine transfer protein (PCTP) subfamily, which was first identified as a gene overexpressed in a choriocarcinoma cell line. Recent studies show that the StarD7 protein facilitates the delivery of phosphatidylcholine to the mitochondria. This review summarizes the latest advances in StarD7 research, focusing on the structural and biochemical features, protein-lipid interactions, and mechanisms that regulate StarD7 expression. The implications of the role of StarD7 in cell proliferation, migration, and differentiation are also discussed.
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21
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Wegner CJ, Kim B, Lee J. Trust your gut: galvanizing nutritional interest in intestinal cholesterol metabolism for protection against cardiovascular diseases. Nutrients 2013; 5:208-22. [PMID: 23325147 PMCID: PMC3571644 DOI: 10.3390/nu5010208] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 01/09/2013] [Accepted: 01/11/2013] [Indexed: 02/08/2023] Open
Abstract
Recent studies have demonstrated that the intestine is a key target organ for overall health and longevity. Complementing these studies is the discovery of the trans-intestinal cholesterol efflux pathway and the emerging role of the intestine in reverse cholesterol transport. The surfacing dynamics of the regulation of cholesterol metabolism in the intestine provides an attractive platform for intestine-specific nutritional intervention strategies to lower blood cholesterol levels for protection against cardiovascular diseases. Notably, there is mounting evidence that stimulation of pathways associated with calorie restriction may have a large effect on the regulation of cholesterol removal by the intestine. However, intestinal energy metabolism, specifically the idiosyncrasies surrounding intestinal responses to energy deprivation, is poorly understood. The goal of this paper is to review recent insights into cholesterol regulation by the intestine and to discuss the potential for positive regulation of intestine-driven cholesterol removal through the nutritional induction of pathways associated with calorie restriction.
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Affiliation(s)
- Casey J Wegner
- Department of Nutritional Sciences, University of Connecticut, 216 Advanced Technology Laboratory Building, 1392 Storrs Road, Storrs, CT 06269, USA.
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22
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Moustafa T, Fickert P, Magnes C, Guelly C, Thueringer A, Frank S, Kratky D, Sattler W, Reicher H, Sinner F, Gumhold J, Silbert D, Fauler G, Höfler G, Lass A, Zechner R, Trauner M. Alterations in lipid metabolism mediate inflammation, fibrosis, and proliferation in a mouse model of chronic cholestatic liver injury. Gastroenterology 2012; 142:140-151.e12. [PMID: 22001865 DOI: 10.1053/j.gastro.2011.09.051] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 09/05/2011] [Accepted: 09/29/2011] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS The liver controls central processes of lipid and bile acid homeostasis. We aimed to investigate whether alterations in lipid metabolism contribute to the pathogenesis of chronic cholestatic liver disease in mice. METHODS We used microarray and metabolic profiling analyses to identify alterations in systemic and hepatic lipid metabolism in mice with disruption of the gene ATP-binding cassette sub-family B member 4 (Abcb4(-/-) mice), a model of inflammation-induced cholestatic liver injury, fibrosis, and cancer. RESULTS Alterations in Abcb4(-/-) mice, compared with wild-type mice, included deregulation of genes that control lipid synthesis, storage, and oxidation; decreased serum levels of cholesterol and phospholipids; and reduced hepatic long-chain fatty acyl-CoAs (LCA-CoA). Feeding Abcb4(-/-) mice the side chain-modified bile acid 24-norursodeoxycholic acid (norUDCA) reversed their liver injury and fibrosis, increased serum levels of lipids, lowered phospholipase and triglyceride hydrolase activities, and restored hepatic LCA-CoA and triglyceride levels. Additional genetic and nutritional studies indicated that lipid metabolism contributed to chronic cholestatic liver injury; crossing peroxisome proliferator-activated receptor (PPAR)-α-deficient mice with Abcb4(-/-) mice (to create double knockouts) or placing Abcb4(-/-) mice on a high-fat diet protected against liver injury, with features similar to those involved in the response to norUDCA. Placing pregnant Abcb4(-/-) mice on high-fat diets prevented liver injury in their offspring. However, fenofibrate, an activator of PPARα, aggravated liver injury in Abcb4(-/-) mice. CONCLUSIONS Alterations in lipid metabolism contribute to the pathogenesis and progression of cholestatic liver disease in mice.
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Affiliation(s)
- Tarek Moustafa
- Laboratory of Experimental and Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
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23
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Otis JP, Sahoo D, Drover VA, Yen CLE, Carey HV. Cholesterol and lipoprotein dynamics in a hibernating mammal. PLoS One 2011; 6:e29111. [PMID: 22195001 PMCID: PMC3240636 DOI: 10.1371/journal.pone.0029111] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2011] [Accepted: 11/21/2011] [Indexed: 01/01/2023] Open
Abstract
Hibernating mammals cease feeding during the winter and rely primarily on stored lipids to fuel alternating periods of torpor and arousal. How hibernators manage large fluxes of lipids and sterols over the annual hibernation cycle is poorly understood. The aim of this study was to investigate lipid and cholesterol transport and storage in ground squirrels studied in spring, summer, and several hibernation states. Cholesterol levels in total plasma, HDL and LDL particles were elevated in hibernators compared with spring or summer squirrels. Hibernation increased plasma apolipoprotein A-I expression and HDL particle size. Expression of cholesterol 7 alpha-hydroxylase was 13-fold lower in hibernators than in active season squirrels. Plasma triglycerides were reduced by fasting in spring but not summer squirrels. In hibernators plasma β-hydroxybutyrate was elevated during torpor whereas triglycerides were low relative to normothermic states. We conclude that the switch to a lipid-based metabolism during winter, coupled with reduced capacity to excrete cholesterol creates a closed system in which efficient use of lipoproteins is essential for survival.
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Affiliation(s)
- Jessica P. Otis
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Daisy Sahoo
- Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Victor A. Drover
- Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Chi-Liang Eric Yen
- Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Hannah V. Carey
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
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24
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Tift MS, Houser DS, Crocker DE. High-density lipoprotein remains elevated despite reductions in total cholesterol in fasting adult male elephant seals (Mirounga angustirostris). Comp Biochem Physiol B Biochem Mol Biol 2011; 159:214-9. [PMID: 21596155 DOI: 10.1016/j.cbpb.2011.04.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 04/22/2011] [Accepted: 04/25/2011] [Indexed: 11/20/2022]
Affiliation(s)
- Michael S Tift
- Department of Biology, Sonoma State University, Rohnert Park, CA 94928, USA.
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25
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Tailleux A, Staels B. Overview of the Measurement of Lipids and Lipoproteins in Mice. ACTA ACUST UNITED AC 2011; 1:265-77. [DOI: 10.1002/9780470942390.mo110001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Anne Tailleux
- Université Lille Nord de France Lille France
- Inserm, U1011 Lille France
- UDSL Lille France
- Institut Pasteur de Lille Lille France
| | - Bart Staels
- Université Lille Nord de France Lille France
- Inserm, U1011 Lille France
- UDSL Lille France
- Institut Pasteur de Lille Lille France
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26
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Hakvoort TBM, Moerland PD, Frijters R, Sokolović A, Labruyère WT, Vermeulen JLM, Ver Loren van Themaat E, Breit TM, Wittink FRA, van Kampen AHC, Verhoeven AJ, Lamers WH, Sokolović M. Interorgan coordination of the murine adaptive response to fasting. J Biol Chem 2011; 286:16332-43. [PMID: 21393243 DOI: 10.1074/jbc.m110.216986] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Starvation elicits a complex adaptive response in an organism. No information on transcriptional regulation of metabolic adaptations is available. We, therefore, studied the gene expression profiles of brain, small intestine, kidney, liver, and skeletal muscle in mice that were subjected to 0-72 h of fasting. Functional-category enrichment, text mining, and network analyses were employed to scrutinize the overall adaptation, aiming to identify responsive pathways, processes, and networks, and their regulation. The observed transcriptomics response did not follow the accepted "carbohydrate-lipid-protein" succession of expenditure of energy substrates. Instead, these processes were activated simultaneously in different organs during the entire period. The most prominent changes occurred in lipid and steroid metabolism, especially in the liver and kidney. They were accompanied by suppression of the immune response and cell turnover, particularly in the small intestine, and by increased proteolysis in the muscle. The brain was extremely well protected from the sequels of starvation. 60% of the identified overconnected transcription factors were organ-specific, 6% were common for 4 organs, with nuclear receptors as protagonists, accounting for almost 40% of all transcriptional regulators during fasting. The common transcription factors were PPARα, HNF4α, GCRα, AR (androgen receptor), SREBP1 and -2, FOXOs, EGR1, c-JUN, c-MYC, SP1, YY1, and ETS1. Our data strongly suggest that the control of metabolism in four metabolically active organs is exerted by transcription factors that are activated by nutrient signals and serves, at least partly, to prevent irreversible brain damage.
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Affiliation(s)
- Theodorus B M Hakvoort
- Tytgat Institute for Liver and Intestinal Research (formerly AMC Liver Center), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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27
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Makovicky P, Dudova M, Tumova E, Rajmon R, Vodkova Z. Experimental study of non-alcoholic fatty liver disease (NAFLD) on a model of starving chickens: Is generalization of steatosis accompanied by fibrosis of the liver tissue? Pathol Res Pract 2011; 207:151-5. [DOI: 10.1016/j.prp.2010.12.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 12/04/2010] [Accepted: 12/13/2010] [Indexed: 01/20/2023]
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