1
|
Tamas C, Tamas F, Kovecsi A, Cehan A, Balasa A. Metabolic Contrasts: Fatty Acid Oxidation and Ketone Bodies in Healthy Brains vs. Glioblastoma Multiforme. Int J Mol Sci 2024; 25:5482. [PMID: 38791520 PMCID: PMC11122426 DOI: 10.3390/ijms25105482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/09/2024] [Accepted: 05/15/2024] [Indexed: 05/26/2024] Open
Abstract
The metabolism of glucose and lipids plays a crucial role in the normal homeostasis of the body. Although glucose is the main energy substrate, in its absence, lipid metabolism becomes the primary source of energy. The main means of fatty acid oxidation (FAO) takes place in the mitochondrial matrix through β-oxidation. Glioblastoma (GBM) is the most common form of primary malignant brain tumor (45.6%), with an incidence of 3.1 per 100,000. The metabolic changes found in GBM cells and in the surrounding microenvironment are associated with proliferation, migration, and resistance to treatment. Tumor cells show a remodeling of metabolism with the use of glycolysis at the expense of oxidative phosphorylation (OXPHOS), known as the Warburg effect. Specialized fatty acids (FAs) transporters such as FAT, FABP, or FATP from the tumor microenvironment are overexpressed in GBM and contribute to the absorption and storage of an increased amount of lipids that will provide sufficient energy used for tumor growth and invasion. This review provides an overview of the key enzymes, transporters, and main regulatory pathways of FAs and ketone bodies (KBs) in normal versus GBM cells, highlighting the need to develop new therapeutic strategies to improve treatment efficacy in patients with GBM.
Collapse
Affiliation(s)
- Corina Tamas
- Doctoral School of Medicine and Pharmacy, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania;
- Department of Neurosurgery, Emergency Clinical County Hospital, 540136 Targu Mures, Romania;
- Department of Neurosurgery, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania
| | - Flaviu Tamas
- Doctoral School of Medicine and Pharmacy, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania;
- Department of Neurosurgery, Emergency Clinical County Hospital, 540136 Targu Mures, Romania;
- Department of Neurosurgery, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania
| | - Attila Kovecsi
- Department of Morphopathology, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania;
- Department of Morphopathology, Emergency Clinical County Hospital, 540136 Targu Mures, Romania
| | - Alina Cehan
- Department of Plastic, Esthetics and Reconstructive Surgery, Emergency Clinical County Hospital, 540136 Targu Mures, Romania;
| | - Adrian Balasa
- Department of Neurosurgery, Emergency Clinical County Hospital, 540136 Targu Mures, Romania;
- Department of Neurosurgery, “George Emil Palade” University of Medicine, Pharmacy, Science and Technology, 540142 Targu Mures, Romania
| |
Collapse
|
2
|
Al-Rashed F, Haddad D, Al Madhoun A, Sindhu S, Jacob T, Kochumon S, Obeid LM, Al-Mulla F, Hannun YA, Ahmad R. ACSL1 is a key regulator of inflammatory and macrophage foaming induced by short-term palmitate exposure or acute high-fat feeding. iScience 2023; 26:107145. [PMID: 37416456 PMCID: PMC10320618 DOI: 10.1016/j.isci.2023.107145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 04/29/2023] [Accepted: 06/12/2023] [Indexed: 07/08/2023] Open
Abstract
Foamy and inflammatory macrophages play pathogenic roles in metabolic disorders. However, the mechanisms that promote foamy and inflammatory macrophage phenotypes under acute-high-fat feeding (AHFF) remain elusive. Herein, we investigated the role of acyl-CoA synthetase-1 (ACSL1) in favoring the foamy/inflammatory phenotype of monocytes/macrophages upon short-term exposure to palmitate or AHFF. Palmitate exposure induced a foamy/inflammatory phenotype in macrophages which was associated with increased ACSL1 expression. Inhibition/knockdown of ACSL1 in macrophages suppressed the foamy/inflammatory phenotype through the inhibition of the CD36-FABP4-p38-PPARδ signaling axis. ACSL1 inhibition/knockdown suppressed macrophage foaming/inflammation after palmitate stimulation by downregulating the FABP4 expression. Similar results were obtained using primary human monocytes. As expected, oral administration of ACSL1 inhibitor triacsin-C in mice before AHFF normalized the inflammatory/foamy phenotype of the circulatory monocytes by suppressing FABP4 expression. Our results reveal that targeting ACSL1 leads to the attenuation of the CD36-FABP4-p38-PPARδ signaling axis, providing a therapeutic strategy to prevent the AHFF-induced macrophage foaming and inflammation.
Collapse
Affiliation(s)
- Fatema Al-Rashed
- Immunology & Microbiology Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Dania Haddad
- Genetics and Bioinformatics Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Ashraf Al Madhoun
- Genetics and Bioinformatics Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
- Animal and Imaging Core Facilities, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Sardar Sindhu
- Immunology & Microbiology Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
- Animal and Imaging Core Facilities, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Texy Jacob
- Immunology & Microbiology Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Shihab Kochumon
- Immunology & Microbiology Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Lina M. Obeid
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Fahd Al-Mulla
- Genetics and Bioinformatics Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| | - Yusuf A. Hannun
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Rasheed Ahmad
- Immunology & Microbiology Department, Dasman Diabetes Institute, Kuwait City, Dasman 15462, Kuwait
| |
Collapse
|
3
|
Kolieb E, Maher SA, Shalaby MN, Alsuhaibani AM, Alharthi A, Hassan WA, El-Sayed K. Vitamin D and Swimming Exercise Prevent Obesity in Rats under a High-Fat Diet via Targeting FATP4 and TLR4 in the Liver and Adipose Tissue. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:13740. [PMID: 36360622 PMCID: PMC9656563 DOI: 10.3390/ijerph192113740] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 10/16/2022] [Accepted: 10/18/2022] [Indexed: 11/05/2022]
Abstract
The prevalence of obesity has risen in the last decades, and it has caused massive health burdens on people's health, especially metabolic and cardiovascular issues. The risk of vitamin D insufficiency is increased by obesity, because adipose tissue alters both the requirements for and bioavailability of vitamin D. Exercise training is acknowledged as having a significant and long-term influence on body weight control; the favorable impact of exercise on obesity and obesity-related co-morbidities has been demonstrated via various mechanisms. The current work illustrated the effects of vitamin D supplementation and exercise on obesity induced by a high-fat diet (HFD) and hepatic steatosis in rats and explored how fatty acid transport protein-4 (FATP4) and Toll-like receptor-4 antibodies (TLR4) might be contributing factors to obesity and related hepatic steatosis. Thirty male albino rats were divided into five groups: group 1 was fed a normal-fat diet, group 2 was fed an HFD, group 3 was fed an HFD and given vitamin D supplementation, group 4 was fed an HFD and kept on exercise, and group 5 was fed an HFD, given vitamin D, and kept on exercise. The serum lipid profile adipokines, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were analyzed, and the pathological changes in adipose and liver tissues were examined. In addition, the messenger-ribonucleic acid (mRNA) expression of FATP4 and immunohistochemical expression of TLR4 in adipose and liver tissues were evaluated. Vitamin D supplementation and exercise improved HFD-induced weight gain and attenuated hepatic steatosis, along with improving the serum lipid profile, degree of inflammation, and serum adipokine levels. The expression of FATP4 and TLR4 in both adipose tissue and the liver was downregulated; it was noteworthy that the group that received vitamin D and was kept on exercise showed also improvement in the histopathological picture of this group. According to the findings of this research, the protective effect of vitamin D and exercise against obesity and HFD-induced hepatic steatosis is associated with the downregulation of FATP4 and TLR4, as well as a reduction in inflammation.
Collapse
Affiliation(s)
- Eman Kolieb
- Medical Physiology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Shymaa Ahmed Maher
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt
- Center of Excellence in Molecular and Cellular Medicine (CEMCM), Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Mohammed Nader Shalaby
- Biological Sciences and Sports Health Department, Faculty of Physical Education, Suez Canal University, Ismailia 41522, Egypt
| | - Amnah Mohammed Alsuhaibani
- Department of Physical Sport Science, College of Education, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Afaf Alharthi
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
| | - Wael A. Hassan
- Department of Pathology, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt
- Department of Basic Sciences, College of Medicine, Sulaiman Alrajhi University, Al Bukayriyah 52726, Saudi Arabia
| | - Karima El-Sayed
- Medical Physiology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt
| |
Collapse
|
4
|
Role of fatty acid transport protein 4 in metabolic tissues: insights into obesity and fatty liver disease. Biosci Rep 2022; 42:231317. [PMID: 35583196 PMCID: PMC9160530 DOI: 10.1042/bsr20211854] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 11/28/2022] Open
Abstract
Fatty acid (FA) metabolism is a series of processes that provide structural substances, signalling molecules and energy. Ample evidence has shown that FA uptake is mediated by plasma membrane transporters including FA transport proteins (FATPs), caveolin-1, fatty-acid translocase (FAT)/CD36, and fatty-acid binding proteins. Unlike other FA transporters, the functions of FATPs have been controversial because they contain both motifs of FA transport and fatty acyl-CoA synthetase (ACS). The widely distributed FATP4 is not a direct FA transporter but plays a predominant function as an ACS. FATP4 deficiency causes ichthyosis premature syndrome in mice and humans associated with suppression of polar lipids but an increase in neutral lipids including triglycerides (TGs). Such a shift has been extensively characterized in enterocyte-, hepatocyte-, and adipocyte-specific Fatp4-deficient mice. The mutants under obese and non-obese fatty livers induced by different diets persistently show an increase in blood non-esterified free fatty acids and glycerol indicating the lipolysis of TGs. This review also focuses on FATP4 role on regulatory networks and factors that modulate FATP4 expression in metabolic tissues including intestine, liver, muscle, and adipose tissues. Metabolic disorders especially regarding blood lipids by FATP4 deficiency in different cell types are herein discussed. Our results may be applicable to not only patients with FATP4 mutations but also represent a model of dysregulated lipid homeostasis, thus providing mechanistic insights into obesity and development of fatty liver disease.
Collapse
|
5
|
Muri J, Corak B, Matsushita M, Baes M, Kopf M. Peroxisomes Are Critical for the Development and Maintenance of B1 and Marginal Zone B Cells but Dispensable for Follicular B Cells and T Cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:839-850. [PMID: 35074867 DOI: 10.4049/jimmunol.2100518] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 12/02/2021] [Indexed: 12/31/2022]
Abstract
Antioxidant systems maintain cellular redox (oxidation-reduction) homeostasis. In contrast with other key redox pathways, such as the thioredoxin system, glutathione, and NF-E2-related factor 2 (Nrf2), little is known about the function of the redox-sensitive organelle "peroxisome" in immune cells. In this study, we show that the absence of peroxisomes in conditional Pex5-deficient mice strikingly results in impaired homeostatic maintenance of innate-like B cells, namely, B1 and marginal zone B cells, which translates into a defective Ab response to Streptococcus pneumoniae Surprisingly, however, follicular B2 cell development, homeostatic maintenance, germinal center reactions, Ab production, class switching, and B cell memory formation were unaffected in Pex5-deficient animals. Similarly, T cell development and responses to viral infections also remained unaltered in the absence of Pex5 Thus, this study highlights the differential requirement of peroxisomes in distinct lymphocyte subtypes and may provide a rationale for specifically targeting peroxisomal metabolism in innate-like B cells in certain forms of B cell malignancies involving B1 cells.
Collapse
Affiliation(s)
- Jonathan Muri
- Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland; and
| | - Basak Corak
- Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland; and
| | - Mai Matsushita
- Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland; and
| | - Myriam Baes
- Lab of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Manfred Kopf
- Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland; and
| |
Collapse
|
6
|
Vogel A, Brunner JS, Hajto A, Sharif O, Schabbauer G. Lipid scavenging macrophages and inflammation. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159066. [PMID: 34626791 DOI: 10.1016/j.bbalip.2021.159066] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 08/18/2021] [Indexed: 12/11/2022]
Abstract
Macrophages are professional phagocytes, indispensable for maintenance of tissue homeostasis and integrity. Depending on their resident tissue, macrophages are exposed to highly diverse metabolic environments. Adapted to their niche, they can contribute to local metabolic turnover through metabolite uptake, conversion, storage and release. Disturbances in tissue homeostasis caused by infection, inflammation or damage dramatically alter the local milieu, impacting macrophage activation status and metabolism. In the case of persisting stimuli, defective macrophage responses ensue, which can promote tissue damage and disease. Especially relevant herein are disbalances in lipid rich environments, where macrophages are crucially involved in lipid uptake and turnover, preventing lipotoxicity. Lipid uptake is to a large extent facilitated by macrophage expressed scavenger receptors that are dynamically regulated and important in many metabolic diseases. Here, we review the receptors mediating lipid uptake and summarize recent findings on their role in health and disease. We further highlight the underlying pathways driving macrophage lipid acquisition and their impact on myeloid metabolic remodelling.
Collapse
Affiliation(s)
- Andrea Vogel
- Institute for Vascular Biology, Centre for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Julia Stefanie Brunner
- Institute for Vascular Biology, Centre for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Alexander Hajto
- Institute for Vascular Biology, Centre for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria
| | - Omar Sharif
- Institute for Vascular Biology, Centre for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria.
| | - Gernot Schabbauer
- Institute for Vascular Biology, Centre for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, Vienna, Austria.
| |
Collapse
|
7
|
Tippetts TS, Holland WL, Summers SA. Cholesterol - the devil you know; ceramide - the devil you don't. Trends Pharmacol Sci 2021; 42:1082-1095. [PMID: 34750017 PMCID: PMC8595778 DOI: 10.1016/j.tips.2021.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 01/20/2023]
Abstract
Ectopic lipids play a key role in numerous pathologies, including heart disease, stroke, and diabetes. Of all the lipids studied, perhaps the most well understood is cholesterol, a widely used clinical biomarker of cardiovascular disease and a target of pharmacological interventions (e.g., statins). Thousands of studies have interrogated the regulation and action of this disease-causing sterol. As a growing body of literature indicates, a new class of lipid-based therapies may be on the horizon. Ceramides are cholesterol-independent biomarkers of heart disease and diabetes in humans. Studies in rodents suggest that they are causative agents of disease, as lowering ceramides through genetic or pharmacological interventions prevents cardiovascular disease and diabetes. Herein, we discuss the evidence supporting the potential of therapeutics targeting ceramides to treat cardiometabolic disease, contrasting it with the robust datasets that drove the creation of cholesterol-lowering pharmaceuticals.
Collapse
Affiliation(s)
| | | | - Scott A. Summers
- Correspondence should be addressed to: Scott A. Summers, Department of Nutrition and Integrative Physiology, University of Utah College of Health, 15N, 2030 East, Rm 3110, Salt Lake City Utah 84112, , Tel: 801-585-9359
| |
Collapse
|
8
|
Montgomery MK, Taddese AZ, Bayliss J, Nie S, Williamson NA, Watt MJ. Hexosaminidase A (HEXA) regulates hepatic sphingolipid and lipoprotein metabolism in mice. FASEB J 2021; 35:e22046. [PMID: 34800307 DOI: 10.1096/fj.202101186r] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 02/03/2023]
Abstract
Hexosaminidase A (HexA), a heterodimer consisting of HEXA and HEXB, converts the ganglioside sphingolipid GM2 to GM3 by removing a terminal N-acetyl-d-galactosamine. HexA enzyme deficiency in humans leads to GM2 accumulation in cells, particularly in neurons, and is associated with neurodegeneration. While HexA and sphingolipid metabolism have been extensively investigated in the context of neuronal lipid metabolism, little is known about the metabolic impact of HexA and ganglioside degradation in other tissues. Here, we focussed on the role of HexA in the liver, which is a major regulator of systemic lipid metabolism. We find that hepatic Hexa expression is induced by lipid availability and increased in the presence of hepatic steatosis, which is associated with increased hepatic GM3 content. To assess the impact of HEXA on hepatic lipid metabolism, we used an adeno-associated virus to overexpress HEXA in the livers of high-fat diet fed mice. HEXA overexpression was associated with increased hepatic GM3 content and increased expression of enzymes involved in the degradation of glycated sphingolipids, ultimately driving sphingomyelin accumulation in the liver. In addition, HEXA overexpression led to substantial proteome remodeling in cell surface lipid rafts, which was associated with increased VLDL processing and secretion, hypertriglyceridemia and ectopic lipid accumulation in peripheral tissues. This study established an important role of HEXA in modulating hepatic sphingolipid and lipoprotein metabolism.
Collapse
Affiliation(s)
- Magdalene K Montgomery
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Amanuiel Z Taddese
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jacqueline Bayliss
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Shuai Nie
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science & Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Nicholas A Williamson
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science & Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Matthew J Watt
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| |
Collapse
|
9
|
Liu Y, Long H, Feng S, Ma T, Wang M, Niu L, Zhang X, Wang L, Lei Y, Chen Y, Wang Q, Xu X. Trait correlated expression combined with eQTL and ASE analyses identified novel candidate genes affecting intramuscular fat. BMC Genomics 2021; 22:805. [PMID: 34749647 PMCID: PMC8577010 DOI: 10.1186/s12864-021-08141-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 10/29/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Intramuscular fat (IMF) content is a determining factor for meat taste. The Luchuan pig is a fat-type local breed in southern China that is famous for its desirable meat quality due to high IMF, however, the crossbred offspring of Luchuan sows and Duroc boars displayed within-population variation on meat quality, and the reason remains unknown. RESULTS In the present study, we identified 212 IMF-correlated genes (FDR ≤ 0.01) using correlation analysis between gene expression level and the value of IMF content. The IMF-correlated genes were significantly enriched in the processes of lipid metabolism and mitochondrial energy metabolism, as well as the AMPK/PPAR signaling pathway. From the IMF-correlated genes, we identified 99 genes associated with expression quantitative trait locus (eQTL) or allele-specific expression (ASE) signals, including 21 genes identified by both cis-eQTL and ASE analyses and 12 genes identified by trans-eQTL analysis. Genome-wide association study (GWAS) of IMF identified a significant QTL on SSC14 (p-value = 2.51E-7), and the nearest IMF-correlated gene SFXN4 (r = 0.28, FDR = 4.00E-4) was proposed as the candidate gene. Furthermore, we highlighted another three novel IMF candidate genes, namely AGT, EMG1, and PCTP, by integrated analysis of GWAS, eQTL, and IMF-gene correlation analysis. CONCLUSIONS The AMPK/PPAR signaling pathway together with the processes of lipid and mitochondrial energy metabolism plays a vital role in regulating porcine IMF content. Trait correlated expression combined with eQTL and ASE analysis highlighted a priority list of genes, which compensated for the shortcoming of GWAS, thereby accelerating the mining of causal genes of IMF.
Collapse
Affiliation(s)
- Yan Liu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China.,Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
| | - Huan Long
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Simin Feng
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Tingting Ma
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Mufeng Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Lizhu Niu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Xinyi Zhang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Lianni Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Yu Lei
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Yilong Chen
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Qiankun Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Xuewen Xu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education & College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China. .,The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China. .,Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China.
| |
Collapse
|
10
|
Urso CJ, Zhou H. Role of CD36 in Palmitic Acid Lipotoxicity in Neuro-2a Neuroblastoma Cells. Biomolecules 2021; 11:1567. [PMID: 34827565 PMCID: PMC8615720 DOI: 10.3390/biom11111567] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 01/21/2023] Open
Abstract
Elevated level of palmitic acid (PA), a long-chain saturated fatty acid (SFA), is lipotoxic to many different types of cells including Neuro-2a (N2a) neuroblastoma cells. CD36 is a multifunctional membrane glycoprotein that acts as a fatty acid translocase (FAT) facilitating the transport of long-chain free fatty acids (FFAs) into cells, serves a fatty acid (FA) sensing function in areas including taste buds and the proximal gut, and acts as a scavenger receptor that binds to many ligands, including FAs, collagen, oxidized low-density lipoproteins, and anionic phospholipids. However, the involvement of CD36 in FA uptake and PA lipotoxicity in N2a cells remains unclear. In this study, we examined FA uptake in BSA- and PA-treated N2a cells and investigated the involvement of CD36 in FA uptake and PA lipotoxicity in N2a cells. Our data showed that PA treatment promoted FA uptake in N2a cells, and that treatment with sulfo-N-succinimidyl oleate (SSO), a CD36 inhibitor, significantly decreased FA uptake in BSA- and PA-treated N2a cells, and ameliorated PA-induced decrease of cell viability, decrease of diploid cells, and increase of tetraploid cells. We also found that CD36 knockdown significantly decreased FA uptake in both BSA- and PA-treated cells as compared to their corresponding wild-type controls, and dramatically attenuated PA-induced cell cycle defects in N2a cells. Our data suggest that CD36 may play a critical role in FA uptake and PA lipotoxicity in N2a cells. CD36 may therefore represent a regulatory target against pathologies caused by excess FAs.
Collapse
Affiliation(s)
| | - Heping Zhou
- Department of Biological Sciences, Seton Hall University, 400 South Orange Avenue, South Orange, NJ 07079, USA;
| |
Collapse
|
11
|
Karunakaran U, Elumalai S, Moon JS, Won KC. CD36 Signal Transduction in Metabolic Diseases: Novel Insights and Therapeutic Targeting. Cells 2021; 10:cells10071833. [PMID: 34360006 PMCID: PMC8305429 DOI: 10.3390/cells10071833] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/14/2021] [Accepted: 07/17/2021] [Indexed: 12/24/2022] Open
Abstract
The cluster of differentiation 36 (CD36) is a scavenger receptor present on various types of cells and has multiple biological functions that may be important in inflammation and in the pathogenesis of metabolic diseases, including diabetes. Here, we consider recent insights into how the CD36 response becomes deregulated under metabolic conditions, as well as the therapeutic benefits of CD36 inhibition, which may provide clues for developing strategies aimed at the treatment or prevention of diabetes associated with metabolic diseases. To facilitate this process further, it is important to pinpoint regulatory mechanisms that are relevant under physiological and pathological conditions. In particular, understanding the mechanisms involved in dictating specific CD36 downstream cellular outcomes will aid in the discovery of potent compounds that target specific CD36 downstream signaling cascades.
Collapse
Affiliation(s)
- Udayakumar Karunakaran
- Innovative Center for Aging Research, Yeungnam University Medical Center, Daegu 42415, Korea; (U.K.); (S.E.)
| | - Suma Elumalai
- Innovative Center for Aging Research, Yeungnam University Medical Center, Daegu 42415, Korea; (U.K.); (S.E.)
| | - Jun-Sung Moon
- Innovative Center for Aging Research, Yeungnam University Medical Center, Daegu 42415, Korea; (U.K.); (S.E.)
- Yeungnam University College of Medicine, Daegu 42415, Korea
- Correspondence: (J.-S.M.); (K.-C.W.); Tel.: +82-53-620-3825 (J.-S.M.); +82-53-620-3846 (K.-C.W.)
| | - Kyu-Chang Won
- Innovative Center for Aging Research, Yeungnam University Medical Center, Daegu 42415, Korea; (U.K.); (S.E.)
- Yeungnam University College of Medicine, Daegu 42415, Korea
- Correspondence: (J.-S.M.); (K.-C.W.); Tel.: +82-53-620-3825 (J.-S.M.); +82-53-620-3846 (K.-C.W.)
| |
Collapse
|
12
|
Akiba Y, Maruta K, Takajo T, Narimatsu K, Said H, Kato I, Kuwahara A, Kaunitz JD. Lipopolysaccharides transport during fat absorption in rodent small intestine. Am J Physiol Gastrointest Liver Physiol 2020; 318:G1070-G1087. [PMID: 32390462 PMCID: PMC7311662 DOI: 10.1152/ajpgi.00079.2020] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/29/2020] [Accepted: 05/06/2020] [Indexed: 02/07/2023]
Abstract
Lipopolysaccharides (LPS) are potent pro-inflammatory molecules that enter the systemic circulation from the intestinal lumen by uncertain mechanisms. We investigated these mechanisms and the effect of exogenous glucagon-like peptide-2 (GLP-2) on LPS transport in the rodent small intestine. Transmucosal LPS transport was measured in Ussing-chambered rat jejunal mucosa. In anesthetized rats, the appearance of fluorescein isothiocyanate (FITC)-LPS into the portal vein (PV) and the mesenteric lymph was simultaneously monitored after intraduodenal perfusion of FITC-LPS with oleic acid and taurocholate (OA/TCA). In vitro, luminally applied LPS rapidly appeared in the serosal solution only with luminal OA/TCA present, inhibited by the lipid raft inhibitor methyl-β-cyclodextrin (MβCD) and the CD36 inhibitor sulfosuccinimidyl oleate (SSO), or by serosal GLP-2. In vivo, perfusion of FITC-LPS with OA/TCA rapidly increased FITC-LPS appearance into the PV, followed by a gradual increase of FITC-LPS into the lymph. Rapid PV transport was inhibited by the addition of MβCD or by SSO, whereas transport into the lymph was inhibited by chylomicron synthesis inhibition. Intraveous injection of the stable GLP-2 analog teduglutide acutely inhibited FITC-LPS transport into the PV, yet accelerated FITC-LPS transport into the lymph via Nω-nitro-l-arginine methyl ester (l-NAME)- and PG97-269-sensitive mechanisms. In vivo confocal microscopy in mouse jejunum confirmed intracellular FITC-LPS uptake with no evidence of paracellular localization. This is the first direct demonstration in vivo that luminal LPS may cross the small intestinal barrier physiologically during fat absorption via lipid raft- and CD36-mediated mechanisms, followed by predominant transport into the PV, and that teduglutide inhibits LPS uptake into the PV in vivo.NEW & NOTEWORTHY We report direct in vivo confirmation of transcellular lipopolysaccharides (LPS) uptake from the intestine into the portal vein (PV) involving CD36 and lipid rafts, with minor uptake via the canonical chylomicron pathway. The gut hormone glucagon-like peptide-2 (GLP-2) inhibited uptake into the PV. These data suggest that the bulk of LPS absorption is via the PV to the liver, helping clarify the mechanism of LPS transport into the PV as part of the "gut-liver" axis. These data do not support the paracellular transport of LPS, which has been implicated in the pathogenesis of the "leaky gut" syndrome.
Collapse
Affiliation(s)
- Yasutada Akiba
- Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, California
- Department of Medicine, University of California, School of Medicine, Los Angeles, California
- Brentwood Biomedical Research Institute, Los Angeles, California
| | - Koji Maruta
- Department of Medicine, University of California, School of Medicine, Los Angeles, California
| | - Takeshi Takajo
- Department of Medicine, University of California, School of Medicine, Los Angeles, California
| | - Kazuyuki Narimatsu
- Department of Medicine, University of California, School of Medicine, Los Angeles, California
| | - Hyder Said
- Department of Medicine, University of California, School of Medicine, Los Angeles, California
| | - Ikuo Kato
- Department of Medical Biochemistry, Kobe Pharmaceutical University, Kobe, Japan
| | - Atsukazu Kuwahara
- Research Unit for Epithelial Physiology, Research Organization of Science and Technology, Ritsumeikan University, Kusatsu, Japan
| | - Jonathan D Kaunitz
- Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, California
- Department of Medicine, University of California, School of Medicine, Los Angeles, California
- Department of Surgery, University of California, School of Medicine, Los Angeles, California
- Brentwood Biomedical Research Institute, Los Angeles, California
| |
Collapse
|
13
|
Ruhanen H, Haridas PAN, Minicocci I, Taskinen JH, Palmas F, di Costanzo A, D'Erasmo L, Metso J, Partanen J, Dalli J, Zhou Y, Arca M, Jauhiainen M, Käkelä R, Olkkonen VM. ANGPTL3 deficiency alters the lipid profile and metabolism of cultured hepatocytes and human lipoproteins. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158679. [PMID: 32151767 DOI: 10.1016/j.bbalip.2020.158679] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/28/2020] [Accepted: 03/04/2020] [Indexed: 02/08/2023]
Abstract
Loss-of-function (LOF) mutations in ANGPTL3, an inhibitor of lipoprotein lipase (LPL), cause a drastic reduction of serum lipoproteins and protect against the development of atherosclerotic cardiovascular disease. Therefore, ANGPTL3 is a promising therapy target. We characterized the impacts of ANGPTL3 depletion on the immortalized human hepatocyte (IHH) transcriptome, lipidome and human plasma lipoprotein lipidome. The transcriptome of ANGPTL3 knock-down (KD) cells showed altered expression of several pathways related to lipid metabolism. Accordingly, ANGPTL3 depleted IHH displayed changes in cellular overall fatty acid (FA) composition and in the lipid species composition of several lipid classes, characterized by abundant n-6 and n-3 polyunsaturated FAs (PUFAs). This PUFA increase coincided with an elevation of lipid mediators, among which there were species relevant for resolution of inflammation, protection from lipotoxic and hypoxia-induced ER stress, hepatic steatosis and insulin resistance or for the recovery from cardiovascular events. Cholesterol esters were markedly reduced in ANGPTL3 KD IHH, coinciding with suppression of the SOAT1 mRNA and protein. ANGPTL3 LOF caused alterations in plasma lipoprotein FA and lipid species composition. All lipoprotein fractions of the ANGPTL3 LOF subjects displayed a marked drop of 18:2n-6, while several highly unsaturated triacylglycerol (TAG) species were enriched. The present work reveals distinct impacts of ANGPTL3 depletion on the hepatocellular lipidome, transcriptome and lipid mediators, as well as on the lipidome of lipoproteins isolated from plasma of ANGPTL3-deficient human subjects. It is important to consider these lipidomics and transcriptomics findings when targeting ANGPTL3 for therapy and translating it to the human context.
Collapse
Affiliation(s)
- Hanna Ruhanen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland; Helsinki University Lipidomics Unit (HiLIPID), Helsinki Institute for Life Science (HiLIFE), Helsinki, Finland
| | | | - Ilenia Minicocci
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Juuso H Taskinen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Francesco Palmas
- Lipid Mediator Unit, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Alessia di Costanzo
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Laura D'Erasmo
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Jari Metso
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | | | - Jesmond Dalli
- Lipid Mediator Unit, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom; Centre for Inflammation and Therapeutic Innovation, Queen Mary University of London, London, UK
| | - You Zhou
- Systems Immunity University Research Institute and Division of Infection & Immunity, Cardiff University, Cardiff, United Kingdom
| | - Marcello Arca
- Department of Translational and Precision Medicine, Sapienza University of Rome, Italy
| | - Matti Jauhiainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Reijo Käkelä
- Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland; Helsinki University Lipidomics Unit (HiLIPID), Helsinki Institute for Life Science (HiLIFE), Helsinki, Finland
| | - Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Anatomy, University of Helsinki, Finland.
| |
Collapse
|
14
|
Summers SA. Ceramides: Nutrient Signals that Drive Hepatosteatosis. J Lipid Atheroscler 2019; 9:50-65. [PMID: 32821721 PMCID: PMC7379074 DOI: 10.12997/jla.2020.9.1.50] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 11/04/2019] [Accepted: 11/10/2019] [Indexed: 12/16/2022] Open
Abstract
Ceramides are minor components of the hepatic lipidome that have major effects on liver function. These products of lipid and protein metabolism accumulate when the energy needs of the hepatocyte have been met and its storage capacity is full, such that free fatty acids start to couple to the sphingoid backbone rather than the glycerol moiety that is the scaffold for glycerolipids (e.g., triglycerides) or the carnitine moiety that shunts them into mitochondria. As ceramides accrue, they initiate actions that protect cells from acute increases in detergent-like fatty acids; for example, they alter cellular substrate preference from glucose to lipids and they enhance triglyceride storage. When prolonged, these ceramide actions cause insulin resistance and hepatic steatosis, 2 of the underlying drivers of cardiometabolic diseases. Herein the author discusses the mechanisms linking ceramides to the development of insulin resistance, hepatosteatosis and resultant cardiometabolic disorders.
Collapse
Affiliation(s)
- Scott A Summers
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| |
Collapse
|
15
|
Abstract
Ceramides are products of metabolism that accumulate in individuals with obesity or dyslipidaemia and alter cellular processes in response to fuel surplus. Their actions, when prolonged, elicit the tissue dysfunction that underlies diabetes and heart disease. Here, we review the history of research on these enigmatic molecules, exploring their discovery and mechanisms of action, the evolutionary pressures that have given them their unique attributes and the potential of ceramide-reduction therapies as treatments for cardiometabolic disease.
Collapse
Affiliation(s)
- Scott A Summers
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Center, University of Utah, Salt Lake City, UT, USA.
| | - Bhagirath Chaurasia
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Center, University of Utah, Salt Lake City, UT, USA
| | - William L Holland
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Center, University of Utah, Salt Lake City, UT, USA
| |
Collapse
|
16
|
Ouellette MÈ, Bérubé JC, Bourget JM, Vallée M, Bossé Y, Fradette J. Linoleic acid supplementation of cell culture media influences the phospholipid and lipid profiles of human reconstructed adipose tissue. PLoS One 2019; 14:e0224228. [PMID: 31639818 PMCID: PMC6805161 DOI: 10.1371/journal.pone.0224228] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/08/2019] [Indexed: 01/09/2023] Open
Abstract
Reconstructed human adipose tissues represent novel tools available to perform in vitro pharmaco-toxicological studies. We used adipose-derived human stromal/stem cells to reconstruct, using tissue engineering techniques, such an adipose tridimensional model. To determine to what extent the in vitro model is representative of its native counterpart, adipogenic differentiation, triglycerides accumulation and phospholipids profiles were analysed. Ingenuity Pathway Analysis software revealed pathways enriched with differentially-expressed genes between native and reconstructed human adipose tissues. Interestingly, genes related to fatty acid metabolism were downregulated in vitro, which could be explained in part by the insufficient amount of essential fatty acids provided by the fetal calf serum used for the culture. Indeed, the lipid profile of the reconstructed human adipose tissues indicated a particular lack of linoleic acid, which could interfere with physiological cell processes such as membrane trafficking, signaling and inflammatory responses. Supplementation in the culture medium was able to influence the lipid profile of the reconstructed human adipose tissues. This study demonstrates the possibility to directly modulate the phospholipid profile of reconstructed human adipose tissues. This reinforces its use as a relevant physiological or pathological model for further pharmacological and metabolic studies of human adipose tissue functions.
Collapse
Affiliation(s)
- Marie-Ève Ouellette
- Centre de Recherche en Organogenèse Expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec -Université Laval Research Center, Québec, QC, Canada
- Department of Surgery, Faculty of Medicine, Université Laval, Québec, Canada
| | - Jean-Christophe Bérubé
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Jean-Michel Bourget
- Centre de Recherche en Organogenèse Expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec -Université Laval Research Center, Québec, QC, Canada
- Department of Surgery, Faculty of Medicine, Université Laval, Québec, Canada
| | - Maud Vallée
- Centre de Recherche en Organogenèse Expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec -Université Laval Research Center, Québec, QC, Canada
- Department of Surgery, Faculty of Medicine, Université Laval, Québec, Canada
| | - Yohan Bossé
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Québec, Canada
| | - Julie Fradette
- Centre de Recherche en Organogenèse Expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec -Université Laval Research Center, Québec, QC, Canada
- Department of Surgery, Faculty of Medicine, Université Laval, Québec, Canada
| |
Collapse
|
17
|
Chaurasia B, Tippetts TS, Mayoral Monibas R, Liu J, Li Y, Wang L, Wilkerson JL, Sweeney CR, Pereira RF, Sumida DH, Maschek JA, Cox JE, Kaddai V, Lancaster GI, Siddique MM, Poss A, Pearson M, Satapati S, Zhou H, McLaren DG, Previs SF, Chen Y, Qian Y, Petrov A, Wu M, Shen X, Yao J, Nunes CN, Howard AD, Wang L, Erion MD, Rutter J, Holland WL, Kelley DE, Summers SA. Targeting a ceramide double bond improves insulin resistance and hepatic steatosis. Science 2019; 365:386-392. [PMID: 31273070 DOI: 10.1126/science.aav3722] [Citation(s) in RCA: 284] [Impact Index Per Article: 56.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 06/14/2019] [Indexed: 12/12/2022]
Abstract
Ceramides contribute to the lipotoxicity that underlies diabetes, hepatic steatosis, and heart disease. By genetically engineering mice, we deleted the enzyme dihydroceramide desaturase 1 (DES1), which normally inserts a conserved double bond into the backbone of ceramides and other predominant sphingolipids. Ablation of DES1 from whole animals or tissue-specific deletion in the liver and/or adipose tissue resolved hepatic steatosis and insulin resistance in mice caused by leptin deficiency or obesogenic diets. Mechanistic studies revealed ceramide actions that promoted lipid uptake and storage and impaired glucose utilization, none of which could be recapitulated by (dihydro)ceramides that lacked the critical double bond. These studies suggest that inhibition of DES1 may provide a means of treating hepatic steatosis and metabolic disorders.
Collapse
Affiliation(s)
- Bhagirath Chaurasia
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - Trevor S Tippetts
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | | | - Jinqi Liu
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Ying Li
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - Liping Wang
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - Joseph L Wilkerson
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - C Rufus Sweeney
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | | | - Doris Hissako Sumida
- School of Dentistry, São Paulo State University (UNESP), Araçatuba 16015, Brazil
| | - J Alan Maschek
- Department of Biochemistry and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - James E Cox
- Department of Biochemistry and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - Vincent Kaddai
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | | | | | - Annelise Poss
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | | | | | - Heather Zhou
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - David G McLaren
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | | | - Ying Chen
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Ying Qian
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | | | - Margaret Wu
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Xiaolan Shen
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Jun Yao
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | | | - Andrew D Howard
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Liangsu Wang
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Mark D Erion
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Jared Rutter
- Department of Biochemistry and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA.,Howard Hughes Medical Institute, Salt Lake City, UT 84112, USA
| | - William L Holland
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA
| | - David E Kelley
- Merck Research Laboratories, Merck, Kenilworth, NJ 07033, USA
| | - Scott A Summers
- Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT 84112, USA.
| |
Collapse
|
18
|
Conophylline inhibits high fat diet-induced non-alcoholic fatty liver disease in mice. PLoS One 2019; 14:e0210068. [PMID: 30689650 PMCID: PMC6349312 DOI: 10.1371/journal.pone.0210068] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 12/14/2018] [Indexed: 01/18/2023] Open
Abstract
Conophylline (CnP), a vinca alkaloid extracted from the leaves of the tropical plant Tabernaemontana divaricate, attenuates hepatic fibrosis in mice. We have previously shown that CnP inhibits non-alcoholic steatohepatitis (NASH) using a methionine-choline-deficient (MCD) diet-fed mouse model. However, little is known about the CnP mediated inhibition of hepatic steatosis in high-fat diet-induced non-alcoholic fatty liver disease (NAFLD) mouse models. CnP (0.5 and 1 μg/g/body weight) was co-administered along with a high-fat diet to male BALB/c mice. After nine weeks of administering the high-fat diet, hepatic steatosis, triglyceride, and hepatic fat metabolism-related markers were examined. Administration of a high-fat diet for 9 weeks was found to induce hepatic steatosis. CnP dose-dependently attenuated the high-fat diet-induced hepatic steatosis. The diet also attenuated hepatic peroxisome proliferator-activated receptor alpha (PPARA) mRNA levels. PPARA is known to be involved in β-oxidation. CnP upregulated the mRNA levels of hepatic PPARA and its target genes, such as carnitine palmitoyl transferase 1 (CPT1) and CPT2, in a dose-dependent manner in the liver. Furthermore, levels of hepatic β-hydroxybutyrate, which is a type of ketone body, were increased by CnP in a dose-dependent manner. Finally, CnP increased the expression of the autophagosomal marker LC3-II and decreased the expression of p62, which are known to be selectively degraded during autophagy. These results indicate that CnP inhibits hepatic steatosis through the stimulation of β-oxidation and autophagy in the liver. Therefore, CnP might prove to be a suitable therapeutic target for NAFLD.
Collapse
|
19
|
Bousseau S, Vergori L, Soleti R, Lenaers G, Martinez MC, Andriantsitohaina R. Glycosylation as new pharmacological strategies for diseases associated with excessive angiogenesis. Pharmacol Ther 2018; 191:92-122. [DOI: 10.1016/j.pharmthera.2018.06.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 06/01/2018] [Indexed: 02/07/2023]
|
20
|
Zhang W, Chen R, Yang T, Xu N, Chen J, Gao Y, Stetler RA. Fatty acid transporting proteins: Roles in brain development, aging, and stroke. Prostaglandins Leukot Essent Fatty Acids 2018; 136:35-45. [PMID: 28457600 PMCID: PMC5650946 DOI: 10.1016/j.plefa.2017.04.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 04/16/2017] [Accepted: 04/20/2017] [Indexed: 12/18/2022]
Abstract
Polyunsaturated fatty acids are required for the brain development and significantly impact aging and stroke. Due to the hydrophobicity of fatty acids, fatty acids transportation related proteins that include fatty acid binding proteins (FABPs), long chain acyl-coA synthase (ACS), fatty acid transportation proteins (FATPs), fatty acid translocase (FAT/CD36) and newly reported major facilitator superfamily domain-containing protein (Mfsd2a) play critical roles in the uptake of various fatty acids, especially polyunsaturated fatty acids. They are not only involved in neurodevelopment, but also have great impact on neurological disease, such as aging related dementia and stroke.
Collapse
Affiliation(s)
- Wenting Zhang
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Ruiying Chen
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Tuo Yang
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Na Xu
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Jun Chen
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
| | - R Anne Stetler
- State Key Laboratory of Medical Neurobiology, Institute of Brain Sciences and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA.
| |
Collapse
|
21
|
Legros N, Pohlentz G, Runde J, Dusny S, Humpf HU, Karch H, Müthing J. Colocalization of receptors for Shiga toxins with lipid rafts in primary human renal glomerular endothelial cells and influence of D-PDMP on synthesis and distribution of glycosphingolipid receptors. Glycobiology 2018; 27:947-965. [PMID: 28535204 DOI: 10.1093/glycob/cwx048] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/17/2017] [Indexed: 12/12/2022] Open
Abstract
Damage of human renal glomerular endothelial cells (HRGECs) of the kidney represents the linchpin in the pathogenesis of the hemolytic uremic syndrome caused by Shiga toxins of enterohemorrhagic Escherichia coli (EHEC). We performed a comprehensive structural analysis of the Stx-receptor glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer, Galα4Galβ4Glcβ1Cer) and globotetraosylceramide (Gb4Cer, GalNAcβ3Galα4Galβ4Glcβ1Cer) and their distribution in lipid raft analog detergent-resistant membranes (DRMs) and nonDRMs prepared from primary HRGECs. Predominant receptor lipoforms were Gb3Cer and Gb4Cer with Cer (d18:1, C16:0), Cer (d18:1, C22:0) and Cer (d18:1, C24:1/C24:0). Stx-receptor GSLs co-distribute with sphingomyelin (SM) and cholesterol as well as flotillin-2 in DRMs, representing the liquid-ordered membrane phase and indicating lipid raft association. Lyso-phosphatidylcholine (lyso-PC) was identified as a nonDRM marker phospholipid of the liquid-disordered membrane phase. Exposure of primary HRGECs to the ceramide analogon d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP) reduced total Gb3Cer and Gb4Cer content, roughly calculated from two biological replicates, down to half and quarter of its primordial content, respectively, but strengthened their prevalence and cholesterol preponderance in DRMs. At the same time, the distribution of PC, SM and lyso-PC to subcellular membrane fractions remained unaffected by D-PDMP treatment. Defining the GSL composition and precise microdomain structures of primary HRGECs may help to develop novel therapeutic options to combat life-threatening EHEC infections.
Collapse
Affiliation(s)
- Nadine Legros
- Institute for Hygiene, University of Münster, Robert-Koch-Str. 41, D-48149 Münster, Germany
| | - Gottfried Pohlentz
- Institute for Hygiene, University of Münster, Robert-Koch-Str. 41, D-48149 Münster, Germany
| | - Jana Runde
- Institute for Food Chemistry, University of Münster, D-48149 Münster, Germany
| | - Stefanie Dusny
- Institute for Food Chemistry, University of Münster, D-48149 Münster, Germany
| | - Hans-Ulrich Humpf
- Institute for Food Chemistry, University of Münster, D-48149 Münster, Germany
| | - Helge Karch
- Institute for Hygiene, University of Münster, Robert-Koch-Str. 41, D-48149 Münster, Germany
| | - Johannes Müthing
- Institute for Hygiene, University of Münster, Robert-Koch-Str. 41, D-48149 Münster, Germany
| |
Collapse
|
22
|
Ayisi CL, Yamei C, Zhao JL. Genes, transcription factors and enzymes involved in lipid metabolism in fin fish. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.aggene.2017.09.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
23
|
Russell J, Du Toit EF, Peart JN, Patel HH, Headrick JP. Myocyte membrane and microdomain modifications in diabetes: determinants of ischemic tolerance and cardioprotection. Cardiovasc Diabetol 2017; 16:155. [PMID: 29202762 PMCID: PMC5716308 DOI: 10.1186/s12933-017-0638-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/22/2017] [Indexed: 02/06/2023] Open
Abstract
Cardiovascular disease, predominantly ischemic heart disease (IHD), is the leading cause of death in diabetes mellitus (DM). In addition to eliciting cardiomyopathy, DM induces a ‘wicked triumvirate’: (i) increasing the risk and incidence of IHD and myocardial ischemia; (ii) decreasing myocardial tolerance to ischemia–reperfusion (I–R) injury; and (iii) inhibiting or eliminating responses to cardioprotective stimuli. Changes in ischemic tolerance and cardioprotective signaling may contribute to substantially higher mortality and morbidity following ischemic insult in DM patients. Among the diverse mechanisms implicated in diabetic impairment of ischemic tolerance and cardioprotection, changes in sarcolemmal makeup may play an overarching role and are considered in detail in the current review. Observations predominantly in animal models reveal DM-dependent changes in membrane lipid composition (cholesterol and triglyceride accumulation, fatty acid saturation vs. reduced desaturation, phospholipid remodeling) that contribute to modulation of caveolar domains, gap junctions and T-tubules. These modifications influence sarcolemmal biophysical properties, receptor and phospholipid signaling, ion channel and transporter functions, contributing to contractile and electrophysiological dysfunction, cardiomyopathy, ischemic intolerance and suppression of protective signaling. A better understanding of these sarcolemmal abnormalities in types I and II DM (T1DM, T2DM) can inform approaches to limiting cardiomyopathy, associated IHD and their consequences. Key knowledge gaps include details of sarcolemmal changes in models of T2DM, temporal patterns of lipid, microdomain and T-tubule changes during disease development, and the precise impacts of these diverse sarcolemmal modifications. Importantly, exercise, dietary, pharmacological and gene approaches have potential for improving sarcolemmal makeup, and thus myocyte function and stress-resistance in this ubiquitous metabolic disorder.
Collapse
Affiliation(s)
- Jake Russell
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - Eugene F Du Toit
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - Jason N Peart
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - Hemal H Patel
- VA San Diego Healthcare System and Department of Anesthesiology, University of California San Diego, San Diego, USA
| | - John P Headrick
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia. .,School of Medical Science, Griffith University, Southport, QLD, 4217, Australia.
| |
Collapse
|
24
|
Nakade Y, Sakamoto K, Yamauchi T, Inoue T, Kobayashi Y, Yamamoto T, Ishii N, Ohashi T, Sumida Y, Ito K, Nakao H, Fukuzawa Y, Umezawa K, Yoneda M. Conophylline inhibits non-alcoholic steatohepatitis in mice. PLoS One 2017; 12:e0178436. [PMID: 28594915 PMCID: PMC5464552 DOI: 10.1371/journal.pone.0178436] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 05/12/2017] [Indexed: 01/18/2023] Open
Abstract
Conophylline (CnP), a vinca alkaloid extracted from the leaves of the tropical plant Ervatamia microphylla, attenuates hepatic fibrosis in mice. However, little is known about whether CnP inhibits steatosis, inflammation, and fibrosis in non-alcoholic steatohepatitis (NASH) in mice. A methionine-choline-deficient (MCD) diet was administered to male db/db mice as a NASH model, and CnP (1 μg/kg/d) was co-administered. Eight weeks after the commencement of the MCD diet, hepatic steatosis, inflammation, and fibrosis, and hepatic fat metabolism-, inflammation-, and fibrosis-related markers were examined. Feeding on an MCD for 8 weeks induced hepatic steatosis, inflammation, and fibrosis. CnP significantly attenuated the MCD-induced increases in hepatic steatosis, as well as hepatic inflammation and fibrosis. The MCD diet increased hepatic transforming growth factor-β (TGF-β) mRNA levels, which are correlated with hepatic steatosis, inflammation, and fibrosis. The diet also attenuated acyl-coenzyme A oxidase 1 (ACOX1) and carnitine palmitoyltransferase 1 (CPT1) mRNA levels, which are involved in β-oxidation. The putative mechanism of the CnP effect involves reduced hepatic TGF-β mRNA levels, and increased mRNA levels of hepatic peroxisome proliferator-activated receptor (PPAR) α and its target genes ACOX1 and CPT1. The results of this study indicate that CnP inhibits steatohepatitis, possibly through the inhibition of hepatic TGF-β mRNA levels, and induces an increase in PPARα mRNA levels, resulting in the attenuation of hepatic steatosis, inflammation, and fibrosis in mice. CnP might accordingly be a suitable therapeutic option for NASH.
Collapse
Affiliation(s)
- Yukiomi Nakade
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
- * E-mail:
| | - Kazumasa Sakamoto
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Taeko Yamauchi
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Tadahisa Inoue
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Yuji Kobayashi
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Takaya Yamamoto
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Norimitsu Ishii
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Tomohiko Ohashi
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Yoshio Sumida
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Kiyoaki Ito
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Haruhisa Nakao
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Yoshitaka Fukuzawa
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| | - Kazuo Umezawa
- Department of Molecular Target Medicine Screening, Aichi Medical University, Nagakute, Aichi, Japan
| | - Masashi Yoneda
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan
| |
Collapse
|
25
|
Wei P, Sun FD, Zuo LM, Qu J, Chen P, Xu LD, Luo SZ. Critical residues and motifs for homodimerization of the first transmembrane domain of the plasma membrane glycoprotein CD36. J Biol Chem 2017; 292:8683-8693. [PMID: 28336533 DOI: 10.1074/jbc.m117.779595] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/09/2017] [Indexed: 12/19/2022] Open
Abstract
The plasma transmembrane (TM) glycoprotein CD36 is critically involved in many essential signaling processes, especially the binding/uptake of long-chain fatty acids and oxidized low-density lipoproteins. The association of CD36 potentially activates cytosolic protein tyrosine kinases that are thought to associate with the C-terminal cytoplasmic tail of CD36. To understand the mechanisms by which CD36 mediates ligand binding and signal transduction, we have characterized the homo-oligomeric interaction of CD36 TM domains in membrane environments and with molecular dynamics (MD) simulations. Analysis of pyrene- and coumarin-labeled TM1 peptides in SDS by FRET confirmed the homodimerization of the CD36 TM1 peptide. Homodimerization assays of CD36 TM domains with the TOXCAT technique showed that its first TM (TM1) domain, but not the second TM (TM2) domain, could homodimerize in a cell membrane. Small-residue, site-specific mutation scanning revealed that the CD36 TM1 dimerization is mediated by the conserved small residues Gly12, Gly16, Ala20, and Gly23 Furthermore, molecular dynamics (MD) simulation studies demonstrated that CD36 TM1 exhibited a switching dimerization with two right-handed packing modes driven by the 12GXXXGXXXA20 and 20AXXG23 motifs, and the mutational effect of G16I and G23I revealed these representative conformations of CD36 TM1. This packing switch pattern of CD36 TM1 homodimer was further examined and confirmed by FRET analysis of monobromobimane (mBBr)-labeled CD36 TM1 peptides. Overall, this work provides a structural basis for understanding the role of TM association in regulating signal transduction via CD36.
Collapse
Affiliation(s)
- Peng Wei
- From the Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.,the School of Basic Medical Science, Beijing University of Chinese Medicine, Beijing 100029, China, and
| | - Fu-de Sun
- From the Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Li-Min Zuo
- the Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, Beijing 100050, China
| | - Jing Qu
- From the Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Peng Chen
- From the Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Li-da Xu
- From the Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Shi-Zhong Luo
- From the Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China,
| |
Collapse
|
26
|
Targeting endothelial metabolism for anti-angiogenesis therapy: A pharmacological perspective. Vascul Pharmacol 2017; 90:8-18. [DOI: 10.1016/j.vph.2017.01.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 01/02/2017] [Indexed: 12/19/2022]
|
27
|
Lu JC, Chiang YT, Lin YC, Chang YT, Lu CY, Chen TY, Yeh CS. Disruption of Lipid Raft Function Increases Expression and Secretion of Monocyte Chemoattractant Protein-1 in 3T3-L1 Adipocytes. PLoS One 2016; 11:e0169005. [PMID: 28030645 PMCID: PMC5193455 DOI: 10.1371/journal.pone.0169005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 12/11/2016] [Indexed: 12/13/2022] Open
Abstract
The adipocyte is unique in its capacity to store lipids. In addition to triglycerides, the adipocyte stores a significant amount of cholesterol. Moreover, obese adipocytes are characterized by a redistribution of cholesterol with depleted cholesterol in the plasma membrane, suggesting that cholesterol perturbation may play a role in adipocyte dysfunction. We used methyl-β-cyclodextrin (MβCD), a molecule with high affinity for cholesterol, to rapidly deplete cholesterol level in differentiated 3T3-L1 adipocytes. We tested whether this perturbation altered adipocyte secretion of monocyte chemoattractant protein-1 (MCP-1), a chemokine that is elevated in obesity and is linked to obesity-associated chronic diseases. Depletion of cholesterol by MβCD increased MCP-1 secretion as well as the mRNA and protein levels, suggesting perturbation at biosynthesis and secretion. Pharmacological inhibition revealed that NF-κB, but not MEK, p38 and JNK, was involved in MβCD-stimulated MCP-1 biosynthesis and secretion in adipocytes. Finally, another cholesterol-binding drug, filipin, also induced MCP-1 secretion without altering membrane cholesterol level. Interestingly, both MβCD and filipin disturbed the integrity of lipid rafts, the membrane microdomains enriched in cholesterol. Thus, the depletion of membrane cholesterol in obese adipocytes may result in dysfunction of lipid rafts, leading to the elevation of proinflammatory signaling and MCP-1 secretion in adipocytes.
Collapse
Affiliation(s)
- Juu-Chin Lu
- Department of Physiology and Pharmacology, Chang Gung University, Taoyuan, Taiwan
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan
- * E-mail:
| | - Yu-Ting Chiang
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Chun Lin
- Department of Physiology and Pharmacology, Chang Gung University, Taoyuan, Taiwan
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Tzu Chang
- Department of Physiology and Pharmacology, Chang Gung University, Taoyuan, Taiwan
| | - Chia-Yun Lu
- Department of Physiology and Pharmacology, Chang Gung University, Taoyuan, Taiwan
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Tzu-Yu Chen
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chia-Shan Yeh
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| |
Collapse
|
28
|
Epstein JB, Smutzer G, Doty RL. Understanding the impact of taste changes in oncology care. Support Care Cancer 2016; 24:1917-31. [DOI: 10.1007/s00520-016-3083-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 01/07/2016] [Indexed: 12/22/2022]
|
29
|
Ong WY, Herr DR, Farooqui T, Ling EA, Farooqui AA. Role of sphingomyelinases in neurological disorders. Expert Opin Ther Targets 2015; 19:1725-42. [DOI: 10.1517/14728222.2015.1071794] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
30
|
Kasumov T, Li L, Li M, Gulshan K, Kirwan JP, Liu X, Previs S, Willard B, Smith JD, McCullough A. Ceramide as a mediator of non-alcoholic Fatty liver disease and associated atherosclerosis. PLoS One 2015; 10:e0126910. [PMID: 25993337 PMCID: PMC4439060 DOI: 10.1371/journal.pone.0126910] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 04/09/2015] [Indexed: 12/12/2022] Open
Abstract
Cardiovascular disease (CVD) is a serious comorbidity in nonalcoholic fatty liver disease (NAFLD). Since plasma ceramides are increased in NAFLD and sphingomyelin, a ceramide metabolite, is an independent risk factor for CVD, the role of ceramides in dyslipidemia was assessed using LDLR-/- mice, a diet-induced model of NAFLD and atherosclerosis. Mice were fed a standard or Western diet (WD), with or without myriocin, an inhibitor of ceramide synthesis. Hepatic and plasma ceramides were profiled and lipid and lipoprotein kinetics were quantified. Hepatic and intestinal expression of genes and proteins involved in insulin, lipid and lipoprotein metabolism were also determined. WD caused hepatic oxidative stress, inflammation, apoptosis, increased hepatic long-chain ceramides associated with apoptosis (C16 and C18) and decreased very-long-chain ceramide C24 involved in insulin signaling. The plasma ratio of ApoB/ApoA1 (proteins of VLDL/LDL and HDL) was increased 2-fold due to increased ApoB production. Myriocin reduced hepatic and plasma ceramides and sphingomyelin, and decreased atherosclerosis, hepatic steatosis, fibrosis, and apoptosis without any effect on oxidative stress. These changes were associated with decreased lipogenesis, ApoB production and increased HDL turnover. Thus, modulation of ceramide synthesis may lead to the development of novel strategies for the treatment of both NAFLD and its associated atherosclerosis.
Collapse
Affiliation(s)
- Takhar Kasumov
- Department of Gastroenterology& Hepatology, Cleveland Clinic, Cleveland, OH, United States of America
- * E-mail: (TK); (AM)
| | - Ling Li
- Department of Research Core Services, Cleveland Clinic, Cleveland, OH, United States of America
| | - Min Li
- Department of Pathobiology, Cleveland Clinic, Cleveland, OH, United States of America
| | - Kailash Gulshan
- Department of Cellular & Molecular Medicine, Cleveland Clinic, Cleveland, OH, United States of America
| | - John P. Kirwan
- Department of Pathobiology, Cleveland Clinic, Cleveland, OH, United States of America
| | - Xiuli Liu
- Department of Anatomic Pathology, Cleveland Clinic, Cleveland, OH, United States of America
| | - Stephen Previs
- Department of Nutrition & Medicine, Case Western Reserve University School of Medicine Cleveland Clinic, Cleveland, OH, United States of America
| | - Belinda Willard
- Department of Research Core Services, Cleveland Clinic, Cleveland, OH, United States of America
| | - Jonathan D. Smith
- Department of Cellular & Molecular Medicine, Cleveland Clinic, Cleveland, OH, United States of America
| | - Arthur McCullough
- Department of Gastroenterology& Hepatology, Cleveland Clinic, Cleveland, OH, United States of America
- Department of Pathobiology, Cleveland Clinic, Cleveland, OH, United States of America
- * E-mail: (TK); (AM)
| |
Collapse
|
31
|
Küch EM, Vellaramkalayil R, Zhang I, Lehnen D, Brügger B, Sreemmel W, Ehehalt R, Poppelreuther M, Füllekrug J. Differentially localized acyl-CoA synthetase 4 isoenzymes mediate the metabolic channeling of fatty acids towards phosphatidylinositol. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1841:227-39. [PMID: 24201376 DOI: 10.1016/j.bbalip.2013.10.018] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 09/20/2013] [Accepted: 10/14/2013] [Indexed: 02/06/2023]
Abstract
The acyl-CoA synthetase 4 (ACSL4) has been implicated in carcinogenesis and neuronal development. Acyl-CoA synthetases are essential enzymes of lipid metabolism, and ACSL4 is distinguished by its preference for arachidonic acid. Two human ACSL4 isoforms arising from differential splicing were analyzed by ectopic expression in COS cells. We found that the ACSL4_v1 variant localized to the inner side of the plasma membrane including microvilli, and was also present in the cytosol. ACSL4_v2 contains an additional N-terminal hydrophobic region; this isoform was located at the endoplasmic reticulum and on lipid droplets. A third isoform was designed de novo by appending a mitochondrial targeting signal. All three ACSL4 variants showed the same specific enzyme activity. Overexpression of the isoenzymes increased cellular uptake of arachidonate to the same degree, indicating that the metabolic trapping of fatty acids is independent of the subcellular localization. Remarkably, phospholipid metabolism was changed by ACSL4 expression. Labeling with arachidonate showed that the amount of newly synthesized phosphatidylinositol was increased by all three ACSL4 isoenzymes but not by ACSL1. This was dependent on the expression level and the localization of the ACSL4 isoform. We conclude that in our model system exogenous fatty acids are channeled preferentially towards phosphatidylinositol by ACSL4 overexpression. The differential localization of the endogenous isoenzymes may provide compartment specific precursors of this anionic phospholipid important for many signaling processes.
Collapse
|
32
|
Modes-of-Action Related to Repeated Dose Toxicity: Tissue-Specific Biological Roles of PPAR γ Ligand-Dependent Dysregulation in Nonalcoholic Fatty Liver Disease. PPAR Res 2014; 2014:432647. [PMID: 24772164 PMCID: PMC3977565 DOI: 10.1155/2014/432647] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 01/13/2014] [Accepted: 01/24/2014] [Indexed: 12/17/2022] Open
Abstract
Comprehensive understanding of the precise mode of action/adverse outcome pathway (MoA/AOP) of chemicals becomes a key step towards superseding the current repeated dose toxicity testing methodology with new generation predictive toxicology tools. The description and characterization of the toxicological MoA leading to non-alcoholic fatty liver disease (NAFLD) are of specific interest, due to its increasing incidence in the modern society. Growing evidence stresses on the PPAR γ ligand-dependent dysregulation as a key molecular initiating event (MIE) for this adverse effect. The aim of this work was to analyze and systematize the numerous scientific data about the steatogenic role of PPAR γ . Over 300 papers were ranked according to preliminary defined criteria and used as reliable and significant sources of data about the PPAR γ -dependent prosteatotic MoA. A detailed analysis was performed regarding proteins which PPAR γ -mediated expression changes had been confirmed to be prosteatotic by most experimental evidence. Two probable toxicological MoAs from PPAR γ ligand binding to NAFLD were described according to the Organisation for Economic Cooperation and Development (OECD) concepts: (i) PPAR γ activation in hepatocytes and (ii) PPAR γ inhibition in adipocytes. The possible events at different levels of biological organization starting from the MIE to the organ response and the connections between them were described in details.
Collapse
|
33
|
Lopez S, Bermudez B, Montserrat-de la Paz S, Jaramillo S, Varela LM, Ortega-Gomez A, Abia R, Muriana FJG. Membrane composition and dynamics: a target of bioactive virgin olive oil constituents. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:1638-56. [PMID: 24440426 DOI: 10.1016/j.bbamem.2014.01.007] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 01/03/2014] [Accepted: 01/07/2014] [Indexed: 12/26/2022]
Abstract
The endogenous synthesis of lipids, which requires suitable dietary raw materials, is critical for the formation of membrane bilayers. In eukaryotic cells, phospholipids are the predominant membrane lipids and consist of hydrophobic acyl chains attached to a hydrophilic head group. The relative balance between saturated, monounsaturated, and polyunsaturated acyl chains is required for the organization and normal function of membranes. Virgin olive oil is the richest natural dietary source of the monounsaturated lipid oleic acid and is one of the key components of the healthy Mediterranean diet. Virgin olive oil also contains a unique constellation of many other lipophilic and amphipathic constituents whose health benefits are still being discovered. The focus of this review is the latest evidence regarding the impact of oleic acid and the minor constituents of virgin olive oil on the arrangement and behavior of lipid bilayers. We highlight the relevance of these interactions to the potential use of virgin olive oil in preserving the functional properties of membranes to maintain health and in modulating membrane functions that can be altered in several pathologies. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
Collapse
Affiliation(s)
- Sergio Lopez
- Laboratory of Cellular and Molecular Nutrition, Instituto de la Grasa, CSIC, 41012 Seville, Spain
| | - Beatriz Bermudez
- Laboratory of Cellular and Molecular Nutrition, Instituto de la Grasa, CSIC, 41012 Seville, Spain
| | | | - Sara Jaramillo
- Laboratory of Phytochemicals and Food Quality, Instituto de la Grasa, CSIC, 41014 Seville, Spain
| | - Lourdes M Varela
- Laboratory of Cellular and Molecular Nutrition, Instituto de la Grasa, CSIC, 41012 Seville, Spain
| | - Almudena Ortega-Gomez
- Laboratory of Cellular and Molecular Nutrition, Instituto de la Grasa, CSIC, 41012 Seville, Spain
| | - Rocio Abia
- Laboratory of Cellular and Molecular Nutrition, Instituto de la Grasa, CSIC, 41012 Seville, Spain
| | - Francisco J G Muriana
- Laboratory of Cellular and Molecular Nutrition, Instituto de la Grasa, CSIC, 41012 Seville, Spain.
| |
Collapse
|
34
|
Fatty acid transporters in skin development, function and disease. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:362-8. [PMID: 24120574 DOI: 10.1016/j.bbalip.2013.09.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/25/2013] [Accepted: 09/30/2013] [Indexed: 12/12/2022]
Abstract
Fatty acids in the epidermis can be incorporated into complex lipids or exist in a free form, and they are crucial to proper functions of the epidermis and its appendages, such as sebaceous glands. Epidermal fatty acids can be synthesized de novo by keratinocytes or taken up from extracutaneous sources in a process that likely involves protein transporters. Several proteins that are expressed in the epidermis have been proposed to facilitate the uptake of long-chain fatty acids (LCFA) in mammalian cells, including fatty acid translocase/CD36, fatty acid binding protein, and fatty acid transport protein (FATP)/very long-chain acyl-CoA synthetase. In this review, we will discuss the mechanisms by which these candidate transporters facilitate the uptake of fatty acids. We will then discuss the clinical implications of defects in these transporters and relevant animal models, including the FATP4 animal models and ichthyosis prematurity syndrome, a congenital ichthyosis caused by FATP4 deficiency. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.
Collapse
|
35
|
Buttet M, Traynard V, Tran TTT, Besnard P, Poirier H, Niot I. From fatty-acid sensing to chylomicron synthesis: role of intestinal lipid-binding proteins. Biochimie 2013; 96:37-47. [PMID: 23958439 DOI: 10.1016/j.biochi.2013.08.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 08/05/2013] [Indexed: 12/31/2022]
Abstract
Today, it is well established that the development of obesity and associated diseases results, in part, from excessive lipid intake associated with a qualitative imbalance. Among the organs involved in lipid homeostasis, the small intestine is the least studied even though it determines lipid bioavailability and largely contributes to the regulation of postprandial hyperlipemia (triacylglycerols (TG) and free fatty acids (FFA)). Several Lipid-Binding Proteins (LBP) are expressed in the small intestine. Their supposed intestinal functions were initially based on what was reported in other tissues, and took no account of the physiological specificity of the small intestine. Progressively, the identification of regulating factors of intestinal LBP and the description of the phenotype of their deletion have provided new insights into cellular and molecular mechanisms involved in fat absorption. This review will discuss the physiological contribution of each LBP in the main steps of intestinal absorption of long-chain fatty acids (LCFA): uptake, trafficking and reassembly into chylomicrons (CM). Moreover, current data indicate that the small intestine is able to adapt its lipid absorption capacity to the fat content of the diet, especially through the coordinated induction of LBP. This adaptation requires the existence of a mechanism of intestinal lipid sensing. Emerging data suggest that the membrane LBP CD36 may operate as a lipid receptor that triggers an intracellular signal leading to the modulation of the expression of LBP involved in CM formation. This event could be the starting point for the optimized synthesis of large CM, which are efficiently degraded in blood. Better understanding of this intestinal lipid sensing might provide new approaches to decrease the prevalence of postprandial hypertriglyceridemia, which is associated with cardiovascular diseases, insulin resistance and obesity.
Collapse
Affiliation(s)
- Marjorie Buttet
- Physiologie de la Nutrition et Toxicologie Team (NUTox), UMR U866 INSERM, Université de Bourgogne, AgroSup Dijon, 1 Esplanade Erasme, 21000 Dijon, France
| | | | | | | | | | | |
Collapse
|
36
|
Siddiqi S, Sheth A, Patel F, Barnes M, Mansbach CM. Intestinal caveolin-1 is important for dietary fatty acid absorption. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1831:1311-21. [PMID: 23665238 PMCID: PMC3751415 DOI: 10.1016/j.bbalip.2013.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 04/29/2013] [Accepted: 05/01/2013] [Indexed: 12/16/2022]
Abstract
How dietary fatty acids are absorbed into the enterocyte and transported to the ER is not established. We tested the possibility that caveolin-1 containing lipid rafts and endocytic vesicles were involved. Apical brush border membranes took up 15% of albumin bound (3)H-oleate whereas brush border membranes from caveolin-1 KO mice took up only 1%. In brush border membranes, the (3)H-oleate was in the detergent resistant fraction of an OptiPrep gradient. On OptiPrep gradients of intestinal cytosol, we also found the (3)H-oleate in the detergent resistant fraction, separate from OptiPrep gradients spiked with (3)H-oleate or (3)H-triacylglycerol. Caveolin-1 immuno-depletion of cytosol removed 91% of absorbed (3)H-oleate whereas immuno-depletion using IgG, or anti-caveolin-2 or -3 or anti-clathrin antibodies removed 20%. Electron microscopy showed the presence of caveolin-1 containing vesicles in WT mouse cytosol that were 4 fold increased by feeding intestinal sacs 1mM oleate. No vesicles were seen in caveolin-1 KO mouse cytosol. Caveolin-1 KO mice gained less weight on a 23% fat diet and had increased fat in their stool compared to WT mice. We conclude that dietary fatty acids are absorbed by caveolae in enterocyte brush border membranes, are endocytosed, and transported in cytosol in caveolin-1 containing endocytic vesicles.
Collapse
Affiliation(s)
- Shahzad Siddiqi
- Division of Gastroenterology, Department of Medicine, The University of Tennessee Health Science Center 38163
| | - Atur Sheth
- Division of Gastroenterology, Department of Medicine, The University of Tennessee Health Science Center 38163
| | - Feenalie Patel
- Division of Gastroenterology, Department of Medicine, The University of Tennessee Health Science Center 38163
| | - Matthew Barnes
- Division of Gastroenterology, Department of Medicine, The University of Tennessee Health Science Center 38163
| | - Charles M. Mansbach
- Division of Gastroenterology, Department of Medicine, The University of Tennessee Health Science Center 38163
- Veterans Affairs Medical Center, Memphis, TN 38104
| |
Collapse
|
37
|
|
38
|
Meiler S, Baumer Y, Huang Z, Hoffmann FW, Fredericks GJ, Rose AH, Norton RL, Hoffmann PR, Boisvert WA. Selenoprotein K is required for palmitoylation of CD36 in macrophages: implications in foam cell formation and atherogenesis. J Leukoc Biol 2013; 93:771-80. [PMID: 23444136 DOI: 10.1189/jlb.1212647] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Selk is an ER transmembrane protein important for calcium flux and macrophage activation, but its role in foam cell formation and atherosclerosis has not been evaluated. BMDMs from Selk(-/-) mice exhibited decreased uptake of modLDL and foam cell formation compared with WT controls, and the differences were eliminated with anti-CD36 blocking antibody. CD36 expression was decreased in TNF-α-stimulated Selk(-/-) BMDMs compared with WT controls. Fluorescence microscopy revealed TNF-α-induced clustering of CD36 in WT BMDMs indicative of lipid raft localization, which was absent in Selk(-/-) BMDMs. Fractionation revealed lower levels of CD36 reaching lipid rafts in TNF-α-stimulated Selk(-/-) BMDMs. Immunoprecipitation showed that Selk(-/-) BMDMs have decreased CD36 palmitoylation, which occurs at the ER membrane and is crucial for stabilizing CD36 expression and directing its localization to lipid rafts. To assess if this phenomenon had a role in atherogenesis, a HFD was fed to irradiated Ldlr(-/-) mice reconstituted with BM from Selk(-/-) or WT mice. Selk was detected in aortic plaques of controls, particularly in macrophages. Selk(-/-) in immune cells led to reduction in atherosclerotic lesion formation without affecting leukocyte migration into the arterial wall. These findings suggest that Selk is important for stable, localized expression of CD36 in macrophages during inflammation, thereby contributing to foam cell formation and atherogenesis.
Collapse
Affiliation(s)
- Svenja Meiler
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii 96813, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Mitsutake S, Igarashi Y. Sphingolipids in Lipid Microdomains and Obesity. VITAMINS & HORMONES 2013; 91:271-84. [DOI: 10.1016/b978-0-12-407766-9.00012-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
40
|
Le Maux S, Giblin L, Croguennec T, Bouhallab S, Brodkorb A. β-Lactoglobulin as a molecular carrier of linoleate: characterization and effects on intestinal epithelial cells in vitro. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:9476-9483. [PMID: 22924475 DOI: 10.1021/jf3028396] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The dairy protein β-lactoglobulin (βlg) is known to bind hydrophobic ligands such as fatty acids. In the present work, we investigated the biological activity in vitro of linoleate once complexed to bovine βlg. Binding of linoleate (C18:2) to bovine βlg was achieved by heating at 60 °C for 30 min at pH 7.4, resulting in a linoleate/βlg molar binding stoichiometry of 1.1, 2.1, and 3.4. Two types of binding sites were determined by ITC titrations. Binding of linoleate induced the formation of covalent dimers and trimers of βlg. The LD(50) on Caco-2 cells after 24 h was 58 μM linoleate. However, cell viability was unaffected when 200 μM linoleate was presented to the Caco-2 cells as part of the βlg complex. The Caco-2 cells did not increase mRNA transcript levels of long chain fatty acid transport genes, FATP4 and FABPpm, or increase levels of the cAMP signal, in response to the presence of 50 μM linoleate alone or as part of the βlg complex. Therefore, it is proposed that βlg can act as a molecular carrier and alter the bioaccessibility of linoleate/linoleic acid.
Collapse
|
41
|
Ebba S, Abarintos RA, Kim DG, Tiyouh M, Stull JC, Movalia A, Smutzer G. The examination of fatty acid taste with edible strips. Physiol Behav 2012; 106:579-86. [PMID: 22521910 DOI: 10.1016/j.physbeh.2012.04.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 03/08/2012] [Accepted: 04/04/2012] [Indexed: 12/19/2022]
Abstract
The objective of this study was to determine whether humans could detect long-chain fatty acids when these lipid molecules are delivered to the oral cavity by edible taste strips. For suprathreshold studies, up to 1.7 μmol of stearic acid or linoleic acid was incorporated into 0.03 mm thick, one-inch square taste strips. Normalized taste intensity values for stearic acid were in the barely detectable range, with values equal to, or slightly above control strips. One-third of test subjects described the taste quality as oily/fatty/waxy. Approximately 75% of test subjects could detect the presence of linoleic acid when this fatty acid was incorporated into dissolvable strips. Normalized taste intensity values for linoleic acid were in the weak to moderate range. The most commonly reported taste quality responses for linoleic acid were fatty/oily/waxy, or bitter. When nasal airflow was obstructed, the perceived taste intensity of linoleic acid decreased by approximately 40%. Taste intensity values and taste quality responses for linoleic acid were then compared among tasters and non-tasters of 6-n-propylthiouracil (PROP). Individuals who could detect the bitter taste of PROP reported higher taste intensity values for linoleic acid compared with PROP non-tasters. However, taste quality responses for linoleic acid were similar among both PROP tasters and PROP non-tasters. These results indicate that humans can detect long-chain fatty acids by both olfactory and non-olfactory pathways when these hydrophobic molecules are delivered to the oral cavity by means of edible taste strips. These studies further show that genetic variation in taste sensitivity to PROP affects chemosensory responses to the cis-unsaturated fatty acid (linoleic acid) in the oral cavity.
Collapse
Affiliation(s)
- Sahbina Ebba
- Department of Biology, Temple University, Philadelphia, PA 19122, USA
| | | | | | | | | | | | | |
Collapse
|
42
|
Abstract
This article reviews the current knowledge and experimental research about the mechanisms by which fatty acids and their derivatives control specific gene expression involved during carcinogenesis. Changes in dietary fatty acids, specifically the polyunsaturated fatty acids of the ω-3 and ω-6 families and some derived eicosanoids from lipoxygenases, cyclooxygenases, and cytochrome P-450, seem to control the activity of transcription factor families involved in cancer cell proliferation or cell death. Their regulation may be carried out either through direct binding to DNA as peroxisome proliferator-activated receptors or via modulation in an indirect manner of signaling pathway molecules (e.g., protein kinase C) and other transcription factors (nuclear factor kappa B and sterol regulatory element binding protein). Knowledge of the mechanisms by which fatty acids control specific gene expression may identify important risk factors for cancer and provide insight into the development of new therapeutic strategies for a better management of whole body lipid metabolism.
Collapse
|
43
|
Shu G, Liao WY, Feng JY, Yu KF, Zhai YF, Wang SB, Khondowe P, Wang XQ, Jiang QY. Active immunization of fatty acid translocase specifically decreased visceral fat deposition in male broilers. Poult Sci 2011; 90:2557-64. [PMID: 22010241 DOI: 10.3382/ps.2010-01238] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipid accumulation of avian adipocytes is mainly dependent upon the fatty acid transmembrane uptake process mediated by membrane proteins, such as fatty acid translocase (FAT/CD36), fatty acid transport protein 1, and caveolin-2. To examine the effects of FAT/CD36 on spatial-specific fat deposition, 60 broiler chickens were randomly allocated to 2 groups by sex. Each male or female group contained 2 subgroups (n = 14-15) inoculated by intramuscular injection with chicken FAT/CD36 or BSA (control) immunogens at 34, 49, and 63 d. The subcutaneous and visceral fat deposits were measured, as were levels of plasma triglyceride and free fatty acid. Serum antibody titer was measured by ELISA. The mRNA expression levels of fatty acid transport-related genes in the adipose tissue of the male broilers were investigated to reveal the relationships among various fatty acid transporters. The results showed that active immunization with FAT/CD36 could significantly decrease the visceral fat of the male broilers by up to 40%, but it had no effect on subcutaneous fat stores of male broilers or on either site of fat deposition in female broilers. The concentration of plasma free fatty acids increased in the experimental groups for both male and female broilers. After the FAT/CD36 immunization, very low density lipoprotein receptor mRNA expression was upregulated in both the subcutaneous and visceral fat of male broilers, whereas peroxisome proliferator-activated receptor γ, FAT/CD36, and acyl-CoA binding protein mRNA expression levels were upregulated only in the visceral fat of male broilers. These results indicated a novel role of chicken FAT/CD36 in fat deposition, with sex- and spatial-specific effects.
Collapse
Affiliation(s)
- G Shu
- College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, China
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Mitchell RW, Hatch GM. Fatty acid transport into the brain: of fatty acid fables and lipid tails. Prostaglandins Leukot Essent Fatty Acids 2011; 85:293-302. [PMID: 21816594 DOI: 10.1016/j.plefa.2011.04.007] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The blood-brain barrier formed by the brain capillary endothelial cells provides a protective barrier between the systemic blood and the extracellular environment of the central nervous system. Brain capillaries are a continuous layer of endothelial cells with highly developed tight junctional complexes and a lack of fenestrations. The presence of these tight junctions in the cerebral microvessel endothelial cells aids in the restriction of movement of molecules and solutes into the brain. Fatty acids are important components of biological membranes, are precursors for the biosynthesis of phospholipids and sphingolipids and are utilized for mitochondrial β-oxidation. The brain is capable of synthesizing only a few fatty acids. Hence, most fatty acids must enter into the brain from the blood. Here we review current mechanisms of transport of free fatty acids into cells and describe how free fatty acids move from the blood into the brain. We discuss both diffusional as well as protein-mediated movement of fatty acids across biological membranes.
Collapse
Affiliation(s)
- Ryan W Mitchell
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Manitoba, A307 Chown Building, 753 McDermot Avenue, Winnipeg, Manitoba, Canada R3E 0T6
| | | |
Collapse
|
45
|
Lynes M, Narisawa S, Millán JL, Widmaier EP. Interactions between CD36 and global intestinal alkaline phosphatase in mouse small intestine and effects of high-fat diet. Am J Physiol Regul Integr Comp Physiol 2011; 301:R1738-47. [PMID: 21900644 DOI: 10.1152/ajpregu.00235.2011] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The mechanisms of the saturable component of long-chain fatty acid (LCFA) transport across the small intestinal epithelium and its regulation by a high-fat diet (HFD) are uncertain. It is hypothesized here that the putative fatty acid translocase/CD36 and intestinal alkaline phosphatases (IAPs) function together to optimize LCFA transport. Phosphorylated CD36 (pCD36) was expressed in mouse enterocytes and dephosphorylated by calf IAP (CIAP). Uptake of fluorescently tagged LCFA into isolated enteroctyes was increased when cells were treated with CIAP; this was blocked with a specific CD36 inhibitor. pCD36 colocalized in enterocytes with the global IAP (gIAP) isozyme and, specifically, coimmunoprecipitated with gIAP, but not the duodenal-specific isozyme (dIAP). Purified recombinant gIAP dephosphorylated immunoprecipitated pCD36, and antiserum to gIAP decreased initial LCFA uptake in enterocytes. Body weight, adiposity, and plasma leptin and triglycerides were significantly increased in HFD mice compared with controls fed a normal-fat diet. HFD significantly increased immunoreactive CD36 and gIAP, but not dIAP, in jejunum, but not duodenum. Uptake of LCFA was increased in a CD36-dependent manner in enterocytes from HFD mice. It is concluded that CD36 exists in its phosphorylated and dephosphorylated states in mouse enterocytes, that pCD36 is a substrate of gIAP, and that dephosphorylation by IAPs results in increased LCFA transport capability. HFD upregulates CD36 and gIAP in parallel and enhances CD36-dependent fatty acid uptake. The interactions between these proteins may be important for efficient fat transport in mouse intestine, but whether the changes in gIAP and CD36 in enterocytes contribute to HFD-induced obesity remains to be determined.
Collapse
Affiliation(s)
- Matthew Lynes
- Department of Biology, Boston University, Boston, Massachusetts 02215, USA
| | | | | | | |
Collapse
|
46
|
Lenz LS, Marx J, Chamulitrat W, Kaiser I, Gröne HJ, Liebisch G, Schmitz G, Elsing C, Straub BK, Füllekrug J, Stremmel W, Herrmann T. Adipocyte-specific inactivation of Acyl-CoA synthetase fatty acid transport protein 4 (Fatp4) in mice causes adipose hypertrophy and alterations in metabolism of complex lipids under high fat diet. J Biol Chem 2011; 286:35578-35587. [PMID: 21808061 DOI: 10.1074/jbc.m111.226530] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Fatp4 exhibits acyl-CoA synthetase activity and is thereby able to catalyze the activation of fatty acids for further metabolism. However, its actual function in most tissues remains unresolved, and its role in cellular fatty acid uptake is still controversial. To characterize Fatp4 functions in adipocytes in vivo, we generated a mouse line with adipocyte-specific inactivation of the Fatp4 gene (Fatp4(A-/-)). Under standard conditions mutant mice showed no phenotypical aberrance. Uptake of radiolabeled palmitic and lignoceric acid into adipose tissue of Fatp4(A-/-) mice was unchanged. When exposed to a diet enriched in long chain fatty acids, Fatp4(A-/-) mice gained more body weight compared with control mice, although they were not consuming more food. Pronounced obesity was accompanied by a thicker layer of subcutaneous fat and greater adipocyte circumference, although expression of genes involved in de novo lipogenesis was not changed. However, the increase in total fat mass was contrasted by a significant decrease in various phospholipids, sphingomyelin, and cholesteryl esters in adipocytes. Livers of Fatp4-deficient animals under a high fat diet exhibited a higher degree of fatty degeneration. Nonetheless, no evidence for changes in insulin sensitivity and adipose inflammation was found. In summary, the results of this study confirm that Fatp4 is not crucial for fatty acid uptake into adipocytes. Instead, under the condition of a diet enriched in long chain fatty acids, adipocyte-specific Fatp4 deficiency results in adipose hypertrophy and profound alterations in the metabolism of complex lipids.
Collapse
Affiliation(s)
- Lena-Solveig Lenz
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg
| | - Jana Marx
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg
| | - Walee Chamulitrat
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg
| | - Iris Kaiser
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg
| | - Hermann-Josef Gröne
- Department of Cellular and Molecular Pathology, German Cancer Research Center, 69120 Heidelberg
| | - Gerhard Liebisch
- Institute of Clinical Chemistry, University of Regensburg, 93042 Regensburg
| | - Gerd Schmitz
- Institute of Clinical Chemistry, University of Regensburg, 93042 Regensburg
| | - Christoph Elsing
- Department of Internal Medicine, St. Elisabeth Hospital, 46225 Dorsten
| | - Beate K Straub
- Department of General Pathology, Institute of Pathology, 69120 Heidelberg
| | - Joachim Füllekrug
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg
| | - Wolfgang Stremmel
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg
| | - Thomas Herrmann
- Department of Internal Medicine IV, University of Heidelberg, 69120 Heidelberg; Department of Internal Medicine I, Klinikum Idar-Oberstein, 55743 Idar-Oberstein, Germany.
| |
Collapse
|
47
|
Mitsutake S, Zama K, Yokota H, Yoshida T, Tanaka M, Mitsui M, Ikawa M, Okabe M, Tanaka Y, Yamashita T, Takemoto H, Okazaki T, Watanabe K, Igarashi Y. Dynamic modification of sphingomyelin in lipid microdomains controls development of obesity, fatty liver, and type 2 diabetes. J Biol Chem 2011; 286:28544-55. [PMID: 21669879 DOI: 10.1074/jbc.m111.255646] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lipid microdomains or caveolae, small invaginations of plasma membrane, have emerged as important elements for lipid uptake and glucose homeostasis. Sphingomyelin (SM) is one of the major phospholipids of the lipid microdomains. In this study, we investigated the physiological function of sphingomyelin synthase 2 (SMS2) using SMS2 knock-out mice, and we found that SMS2 deficiency prevents high fat diet-induced obesity and insulin resistance. Interestingly, in the liver of SMS2 knock-out mice, large and mature lipid droplets were scarcely observed. Treatment with siRNA for SMS2 also decreased the large lipid droplets in HepG2 cells. Additionally, the siRNA of SMS2 decreased the accumulation of triglyceride in liver of leptin-deficient (ob/ob) mice, strongly suggesting that SMS2 is involved in lipid droplet formation. Furthermore, we found that SMS2 exists in lipid microdomains and partially associates with the fatty acid transporter CD36/FAT and with caveolin 1, a scaffolding protein of caveolae. Because CD36/FAT and caveolin 1 exist in lipid microdomains and are coordinately involved in lipid droplet formation, SMS2 is implicated in the modulation of the SM in lipid microdomains, resulting in the regulation of CD36/FAT and caveolae. Here, we established new cell lines, in which we can completely distinguish SMS2 activity from SMS1 activity, and we demonstrated that SMS2 could convert ceramide produced in the outer leaflet of the plasma membrane into SM. Our findings demonstrate the novel and dynamic regulation of lipid microdomains via conformational changes in lipids on the plasma membrane by SMS2, which is responsible for obesity and type 2 diabetes.
Collapse
Affiliation(s)
- Susumu Mitsutake
- Department of Biomembrane and Biofunctional Chemistry, Faculty of Advanced Life Science, Hokkaido University, Sapporo 001-0021, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Tran TTT, Poirier H, Clément L, Nassir F, Pelsers MMAL, Petit V, Degrace P, Monnot MC, Glatz JFC, Abumrad NA, Besnard P, Niot I. Luminal lipid regulates CD36 levels and downstream signaling to stimulate chylomicron synthesis. J Biol Chem 2011; 286:25201-10. [PMID: 21610069 DOI: 10.1074/jbc.m111.233551] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The membrane glycoprotein CD36 binds nanomolar concentrations of long chain fatty acids (LCFA) and is highly expressed on the luminal surface of enterocytes. CD36 deficiency reduces chylomicron production through unknown mechanisms. In this report, we provide novel insights into some of the underlying mechanisms. Our in vivo data demonstrate that CD36 gene deletion in mice does not affect LCFA uptake and subsequent esterification into triglycerides by the intestinal mucosa exposed to the micellar LCFA concentrations prevailing in the intestine. In rodents, the CD36 protein disappears early from the luminal side of intestinal villi during the postprandial period, but only when the diet contains lipids. This drop is significant 1 h after a lipid supply and associates with ubiquitination of CD36. Using CHO cells expressing CD36, it is shown that the digestion products LCFA and diglycerides trigger CD36 ubiquitination. In vivo treatment with the proteasome inhibitor MG132 prevents the lipid-mediated degradation of CD36. In vivo and ex vivo, CD36 is shown to be required for lipid activation of ERK1/2, which associates with an increase of the key chylomicron synthesis proteins, apolipoprotein B48 and microsomal triglyceride transfer protein. Therefore, intestinal CD36, possibly through ERK1/2-mediated signaling, is involved in the adaptation of enterocyte metabolism to the postprandial lipid challenge by promoting the production of large triglyceride-rich lipoproteins that are rapidly cleared in the blood. This suggests that CD36 may be a therapeutic target for reducing the postprandial hypertriglyceridemia and associated cardiovascular risks.
Collapse
Affiliation(s)
- Thi Thu Trang Tran
- Physiologie de la Nutrition, U866 INSERM/Université de Bourgogne, AgroSup Dijon, 21000 Dijon, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Lauritzen L, Carlson SE. Maternal fatty acid status during pregnancy and lactation and relation to newborn and infant status. MATERNAL & CHILD NUTRITION 2011; 7 Suppl 2:41-58. [PMID: 21366866 PMCID: PMC6860497 DOI: 10.1111/j.1740-8709.2011.00303.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The present review of determinants of infant fatty acid status was undertaken as part of a conference on 'Fatty acid status in early life in low-income countries: determinants and consequences'. Emphasis is placed on the essential fatty acids, and particularly the physiologically important long chain polyunsaturated fatty acids (LCPUFAs) of 20 and 22 carbons. We are unaware of any studies of determinants of infant fatty acid status in populations with a cultural dietary pattern with low amounts of linoleic acid (LA, 18:2n-6) and α-linolenic acid (ALA,18:3n-3). Many reports suggest that there may be adverse health effects related to the increased proportion of LA in relation to ALA, which have occurred worldwide due to the increased availability of vegetable oils high in LA. The issue of dietary n-6 to n-3 balance may apply to infant fatty acid status both during fetal and post-natal life; however, this review focuses on the n-3 and n-6 LCPUFA, in particular, docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6), which are the predominant n-3 and n-6 LCPUFA found in cell membranes. The evidence that these fatty acids are preferentially transferred from maternal to fetal circulation across the placenta, and the sources and mechanisms for this transfer, are reviewed. We also address the sources of DHA and AA for the newborn including human milk DHA and AA and the factors that influence maternal DHA status and consequently the amount of DHA available for transfer to the fetus and infant via human milk.
Collapse
Affiliation(s)
- Lotte Lauritzen
- Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 30, Frederiksberg, Denmark.
| | | |
Collapse
|
50
|
Khnykin D, Miner JH, Jahnsen F. Role of fatty acid transporters in epidermis: Implications for health and disease. DERMATO-ENDOCRINOLOGY 2011; 3:53-61. [PMID: 21695012 PMCID: PMC3117002 DOI: 10.4161/derm.3.2.14816] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 01/07/2011] [Accepted: 01/13/2011] [Indexed: 12/31/2022]
Abstract
Skin epidermis is an active site of lipid synthesis. The intercellular lipids of human stratum corneum (SC) are unique in composition and quite different from the lipids found in most biological membranes. The three major lipids in the SC are free fatty acids, cholesterol and ceramides. Fatty acids can be synthesized by keratinocytes de novo and, in addition, need to be taken up from the circulation. The latter process has been shown to be protein mediated, and several fatty acid transporters are expressed in skin. Recent studies of transgenic and knockout animal models for fatty acid transporters and the identification of fatty acid transport protein 4 (FATP4 or SLC27A4) mutations as causative for Ichthyosis Prematurity Syndrome highlight the vital roles of fatty acid transport and metabolism in skin homeostasis. This review provides an overview of our current understanding of the role of fatty acids and their transporters in cutaneous biology, including their involvement in epidermal barrier generation and skin inflammation.
Collapse
Affiliation(s)
- Denis Khnykin
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT); Department of Pathology; Oslo University Hospital-Rikshospitalet; Oslo, Norway
| | | | | |
Collapse
|