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Gao F, Tom E, Rydz C, Cho W, Kolesnikov AV, Sha Y, Papadam A, Jafari S, Joseph A, Ahanchi A, Saraei NBS, Lyon D, Foik A, Nie Q, Grassmann F, Kefalov VJ, Skowronska-Krawczyk D. Polyunsaturated Fatty Acid - mediated Cellular Rejuvenation for Reversing Age-related Vision Decline. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.01.601592. [PMID: 39005302 PMCID: PMC11244954 DOI: 10.1101/2024.07.01.601592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
The retina is uniquely enriched in polyunsaturated fatty acids (PUFAs), which are primarily localized in cell membranes, where they govern membrane biophysical properties such as diffusion, permeability, domain formation, and curvature generation. During aging, alterations in lipid metabolism lead to reduced content of very long-chain PUFAs (VLC-PUFAs) in the retina, and this decline is associated with normal age-related visual decline and pathological age-related macular degeneration (AMD). ELOVL2 (Elongation of very-long-chain fatty acids-like 2) encodes a transmembrane protein that produces precursors to docosahexaenoic acid (DHA) and VLC-PUFAs, and methylation level of its promoter is currently the best predictor of chronological age. Here, we show that mice lacking ELOVL2-specific enzymatic activity (Elovl2 C234W ) have impaired contrast sensitivity and slower rod response recovery following bright light exposure. Intravitreal supplementation with the direct product of ELOVL2, 24:5n-3, in aged animals significantly improved visual function and reduced accumulation of ApoE, HTRA1 and complement proteins in sub-RPE deposits. At the molecular level, the gene expression pattern observed in retinas supplemented with 24:5n-3 exhibited a partial rejuvenation profile, including decreased expression of aging-related genes and a transcriptomic signature of younger retina. Finally, we present the first human genetic data showing significant association of several variants in the human ELOVL2 locus with the onset of intermediate AMD, underlying the translational significance of our findings. In sum, our study identifies novel therapeutic opportunities and defines ELOVL2 as a promising target for interventions aimed at preventing age-related vision loss.
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Affiliation(s)
- Fangyuan Gao
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
| | - Emily Tom
- Department of Physiology and Biophysics, School of Medicine, University of California Irvine, CA
| | - Cezary Rydz
- Department of Physiology and Biophysics, School of Medicine, University of California Irvine, CA
| | - William Cho
- Department of Physiology and Biophysics, School of Medicine, University of California Irvine, CA
| | - Alexander V. Kolesnikov
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
| | - Yutong Sha
- Department of Mathematics, University of California Irvine, CA
| | | | - Samantha Jafari
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
| | - Andrew Joseph
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
| | - Ava Ahanchi
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
| | - Nika Balalaei Someh Saraei
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
| | - David Lyon
- Department of Anatomy and Neurobiology, School of Medicine, University of California Irvine, CA
| | - Andrzej Foik
- International Centre for Translational Eye Research, Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Qing Nie
- Department of Mathematics, University of California Irvine, CA
| | - Felix Grassmann
- Institute for Clinical Research and System Medicine, Health and Medical University, Potsdam, Germany
| | - Vladimir J. Kefalov
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
- Department of Physiology and Biophysics, School of Medicine, University of California Irvine, CA
| | - Dorota Skowronska-Krawczyk
- Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA
- Department of Physiology and Biophysics, School of Medicine, University of California Irvine, CA
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2
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Song C, Wade A, Rainier JD. A gram-scale synthesis of very-long chain polyunsaturated fatty acids (VLC-PUFAs). Org Biomol Chem 2024; 22:3951-3954. [PMID: 38686739 DOI: 10.1039/d4ob00536h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
This manuscript describes our third generation, gram-scale synthesis of very long chain-polyunsaturated fatty acids (VLC-PUFAs), a unique and increasingly important class of lipids. Critical to this work and what makes it different from our previous approach to this family was the avoidance of oxidation sequences. Central to accomplishing this involved the use of a Negishi coupling reaction between the acid chloride derived from DHA and a saturated alkyl zinc reaction. Overall, the general approach required 6 synthetic transformations from DHA and was accomplished with an overall yield of 40%.
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Affiliation(s)
- Changqing Song
- Department of Chemistry, 315 South, 1100 East, University of Utah, Salt Lake City, Utah, 84112, USA.
| | - Alex Wade
- Department of Chemistry, 315 South, 1100 East, University of Utah, Salt Lake City, Utah, 84112, USA.
| | - Jon D Rainier
- Department of Chemistry, 315 South, 1100 East, University of Utah, Salt Lake City, Utah, 84112, USA.
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3
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Nwagbo U, Parvez S, Maschek JA, Bernstein PS. Elovl4b knockout zebrafish as a model for ocular very-long-chain PUFA deficiency. J Lipid Res 2024; 65:100518. [PMID: 38342437 PMCID: PMC10940177 DOI: 10.1016/j.jlr.2024.100518] [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: 11/02/2023] [Revised: 02/03/2024] [Accepted: 02/06/2024] [Indexed: 02/13/2024] Open
Abstract
Very-long-chain PUFAs (VLC-PUFAs) are a group of lipids with chain lengths >24 carbons, and the ELOVL4 (elongation of very-long-chain FA-4) enzyme is responsible for vertebrate VLC-PUFA biosynthesis. Studies on the role of VLC-PUFAs in vision have been hindered because of the need for adequate animal models to capture the global loss of VLC-PUFAs. Since homozygous Elovl4 ablation is lethal in neonatal mice because of catastrophic drying from the loss of their protective skin barrier, we established a zebrafish (Danio rerio) model of Elovl4 ablation. We generated Elovl4b KO zebrafish by creating a 56-bp deletion mutation in exon 2 of the Elovl4b gene using CRISPR-Cas9. We used GC-MS and LC-MS/MS to analyze the VLC-PUFA and lipid profiles from wild-type and Elovl4b KO fish eyes. We also performed histology and visual-behavioral tests. We found that heterozygous and homozygous Elovl4b KO zebrafish eyes had altered lipid profiles and a significantly lower C30 to C36 VLC-PUFA abundance than wild-type fish. Moreover, Elovl4b+/- and Elovl4b-/- KO larvae had significantly lower motor activity in response to light-dark cycles than their age-matched controls. Elovl4b-/- adult fish showed no obvious differences in gross retinal morphology and lamination compared with wild type, except for the presence of lipid droplets within the retinal pigment epithelial cell layer of Elovl4b-/- fish. Our data indicate that the loss of Elovl4b in zebrafish changes ocular lipid profiles and leads to visual abnormalities and subtle retinal changes. These findings highlight the use of zebrafish as a model for VLC-PUFA depletion and ELOVL4-related dysfunction.
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Affiliation(s)
- Uzoamaka Nwagbo
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA; Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA
| | - Saba Parvez
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA
| | - J Alan Maschek
- Metabolomics Core, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - Paul S Bernstein
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA; Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA.
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4
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Gong C, Guo Z, Hu Y, Yang Z, Xia J, Yang X, Xie W, Wang S, Wu Q, Ye W, Zhou X, Turlings TCJ, Zhang Y. A Horizontally Transferred Plant Fatty Acid Desaturase Gene Steers Whitefly Reproduction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306653. [PMID: 38145364 PMCID: PMC10933598 DOI: 10.1002/advs.202306653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/05/2023] [Indexed: 12/26/2023]
Abstract
Polyunsaturated fatty acids (PUFAs) are essential nutrients for all living organisms. PUFA synthesis is mediated by Δ12 desaturases in plants and microorganisms, whereas animals usually obtain PUFAs through their diet. The whitefly Bemisia tabaci is an extremely polyphagous agricultural pest that feeds on phloem sap of many plants that do not always provide them with sufficient PUFAs. Here, a plant-derived Δ12 desaturase gene family BtFAD2 is characterized in B. tabaci and it shows that the BtFAD2-9 gene enables the pest to synthesize PUFAs, thereby significantly enhancing its fecundity. The role of BtFAD2-9 in reproduction is further confirmed by transferring the gene to Drosophila melanogaster, which also increases the fruit fly's reproduction. These findings reveal an extraordinary evolutionary scenario whereby a phytophagous insect acquired a family of plant genes that enables it to synthesize essential nutrients, thereby lessening its nutritional dependency and allowing it to feed and reproduce on many host plants.
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Affiliation(s)
- Cheng Gong
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Zhaojiang Guo
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Yuan Hu
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Zezhong Yang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
- Institute of Plant ProtectionTianjin Academy of Agricultural SciencesTianjin300381China
| | - Jixing Xia
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Xin Yang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Wen Xie
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Shaoli Wang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Qingjun Wu
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Wenfeng Ye
- Laboratory of Fundamental and Applied Research in Chemical EcologyInstitute of BiologyUniversity of NeuchâtelNeuchâtelCH‐2000Switzerland
| | - Xuguo Zhou
- Department of EntomologyUniversity of KentuckyLexingtonKY40546‐0091USA
| | - Ted C. J. Turlings
- Laboratory of Fundamental and Applied Research in Chemical EcologyInstitute of BiologyUniversity of NeuchâtelNeuchâtelCH‐2000Switzerland
| | - Youjun Zhang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
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5
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Tobin D, Svensen H, Shanmugasundaram D, Ruyter B, Stoknes I, Dornish M. Toxicological evaluation of a fish oil concentrate containing Very Long Chain Fatty Acids. Food Chem Toxicol 2024; 186:114518. [PMID: 38387522 DOI: 10.1016/j.fct.2024.114518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 02/24/2024]
Abstract
Very long chain fatty acids (VLCFA) have a chain length ≥24 carbons. Fish contain low levels of these fatty acids. A commercial oil called EPAX® Evolve 05 with an up-concentration of VLCFAs of approximately 10 times, has been developed as a dietary supplement by Epax Norway AS. A series of toxicological studies were performed using mice and rats to determine the safety and toxicity of repeat dosing with a gavage administered VLCFA formulation. The results suggest transient lipid accumulation in kidneys and liver. Lipid accumulation was seen with the test item and with the soya control but was not dose related. Liver and kidney lipid accumulation, whilst present in 14- day repeat dose study, was absent in a 90-day rat study. No treatment-effect was seen in urine analysis in any of the studies. No treatment-related effects were seen with a functional observation battery, ophthalmological examination, haematology, urine analysis, oestrus cycle, thyroid hormones, organ weight, or histopathology. In the 90-day study the liver enzymes ALP, AST and ALT were statistically significantly increased with test item but within control values. There were no associated histological findings in the liver suggesting there was no toxic effect and the normalisation of values for all liver enzymes in the recovery groups suggests an adaptive response rather than a prevailing toxic response. The no-observed-adverse-effect level (NOAEL) was determined as 1200 mg VLCFA/kg b.w./day.
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6
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Heyen S, Schneider V, Hüppe L, Meyer B, Wilkes H. Variations of intact phospholipid compositions in the digestive system of Antarctic krill, Euphausia superba, between summer and autumn. PLoS One 2023; 18:e0295677. [PMID: 38157351 PMCID: PMC10756546 DOI: 10.1371/journal.pone.0295677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 11/28/2023] [Indexed: 01/03/2024] Open
Abstract
The biochemical composition of Antarctic krill, Euphausia superba, is largely determined by their feeding behaviour. As they supply energy for animals of a higher trophic level and are also commercialized for human consumption, the interest in research on the species is high. Lipids, especially phospholipids, make up a high proportion of dry weight in krill. Seasonal changes are well documented in the fingerprint of free fatty acids analysed after hydrolysis of phospholipids, but the underlying intact polar lipids are rarely considered. In this study, we evaluated the compositions of intact phospholipids (IPLs) in the stomach, digestive gland and hind gut of Antarctic krill caught in summer and autumn at the Antarctic Peninsula region. Using high-resolution mass spectrometry, the fatty acid composition of 179 intact phospholipids could be resolved. Most IPLs were phosphatidylcholines, followed by phosphatidylethanolamines. Several very long chain polyunsaturated fatty acids up to 38:8, which have not been reported in krill before, were identified. The composition shifted to higher molecular weight IPLs with a higher degree of unsaturation for summer samples, especially for samples of the digestive gland. The data supplied in this paper provides new insights into lipid dynamics between summer and autumn usually described by free fatty acid biomarkers.
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Affiliation(s)
- Simone Heyen
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Vivien Schneider
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Lukas Hüppe
- Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
- Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Bettina Meyer
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
- Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
- Helmholtz Institute for Marine Functional Biodiversity (HIFMB), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Heinz Wilkes
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
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7
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Yang ZH, Gorusupudi A, Lydic TA, Mondal AK, Sato S, Yamazaki I, Yamaguchi H, Tang J, Rojulpote KV, Lin AB, Decot H, Koch H, Brock DC, Arunkumar R, Shi ZD, Yu ZX, Pryor M, Kun JF, Swenson RE, Swaroop A, Bernstein PS, Remaley AT. Dietary fish oil enriched in very-long-chain polyunsaturated fatty acid reduces cardiometabolic risk factors and improves retinal function. iScience 2023; 26:108411. [PMID: 38047069 PMCID: PMC10692724 DOI: 10.1016/j.isci.2023.108411] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 08/31/2023] [Accepted: 11/03/2023] [Indexed: 12/05/2023] Open
Abstract
Very-long-chain polyunsaturated fatty acids (VLCPUFAs; C24-38) constitute a unique class of PUFA that have important biological roles, but the lack of a suitable dietary source has limited research in this field. We produced an n-3 C24-28-rich VLCPUFA-oil concentrated from fish oil to study its bioavailability and physiological functions in C57BL/6J mice. The serum and retinal C24:5 levels increased significantly compared to control after a single-dose gavage, and VLCPUFAs were incorporated into the liver, brain, and eyes after 8-week supplementation. Dietary VLCPUFAs resulted in favorable cardiometabolic changes, and improved electroretinography responses and visual performance. VLCPUFA supplementation changed the expression of genes involved in PPAR signaling pathways. Further in vitro studies demonstrated that the VLCPUFA-oil and chemically synthesized C24:5 are potent agonists for PPARs. The multiple potential beneficial effects of fish oil-derived VLCPUFAs on cardiometabolic risk and eye health in mice support future efforts to develop VLCPUFA-oil into a supplemental therapy.
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Affiliation(s)
- Zhi-Hong Yang
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Aruna Gorusupudi
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, Salt Lake City, UT 84132, USA
| | - Todd A. Lydic
- Department of Physiology, Collaborative Mass Spectrometry Core, Michigan State University, East Lansing, MI 48824, USA
| | - Anupam K. Mondal
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, NIH, Bethesda, MD 20892, USA
| | - Seizo Sato
- Central Research Laboratory, Nissui Corporation, 1-32-3 Nanakuni, Hachioji, Tokyo 192-0991, Japan
| | - Isao Yamazaki
- Central Research Laboratory, Nissui Corporation, 1-32-3 Nanakuni, Hachioji, Tokyo 192-0991, Japan
| | - Hideaki Yamaguchi
- Central Research Laboratory, Nissui Corporation, 1-32-3 Nanakuni, Hachioji, Tokyo 192-0991, Japan
| | - Jingrong Tang
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Krishna Vamsi Rojulpote
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Anna B. Lin
- Department of Physiology, Collaborative Mass Spectrometry Core, Michigan State University, East Lansing, MI 48824, USA
| | - Hannah Decot
- Department of Physiology, Collaborative Mass Spectrometry Core, Michigan State University, East Lansing, MI 48824, USA
| | - Hannah Koch
- Department of Physiology, Collaborative Mass Spectrometry Core, Michigan State University, East Lansing, MI 48824, USA
| | - Daniel C. Brock
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, NIH, Bethesda, MD 20892, USA
| | - Ranganathan Arunkumar
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, Salt Lake City, UT 84132, USA
| | - Zhen-Dan Shi
- Chemistry and Synthesis Center, NHLBI, NIH, Bethesda, MD 20892, USA
| | - Zu-Xi Yu
- Pathology Core, NHLBI, NIH, Bethesda, MD 20892, USA
| | - Milton Pryor
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Julia F. Kun
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Rolf E. Swenson
- Chemistry and Synthesis Center, NHLBI, NIH, Bethesda, MD 20892, USA
| | - Anand Swaroop
- Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute, NIH, Bethesda, MD 20892, USA
| | - Paul S. Bernstein
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, Salt Lake City, UT 84132, USA
| | - Alan T. Remaley
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
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8
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Tobin D, Svensen H, Stoknes I, Dornish M. Genotoxicity evaluation of a fish oil concentrate containing Very Long Chain Fatty Acids. Toxicol Rep 2023; 11:249-258. [PMID: 37752908 PMCID: PMC10518352 DOI: 10.1016/j.toxrep.2023.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/29/2023] [Accepted: 09/10/2023] [Indexed: 09/28/2023] Open
Abstract
Very long chain fatty acids (VLCFAs) are lipids found in fish with a chain length longer than C22. They represent a minor lipid fraction composing of less than 1% of the total lipid. EPAX® EVOLVE 05 is a concentrate of VLCFAs providing roughly 10 times the amount found in fish. Here we report genotoxocity studies performed in cell culture and using a rat model. No genotoxicity was noted in a bacterial reverse mutation test (AMES test). An in vitro micronucleus assay was negative with a 4-hr test item incubation but a 24-hr incubation resulted in a positive signal. This prompted further study using an in vivo Sprague Dawley rat model. Test item exposure was demonstrated by plasma measurements from Sprague Dawley rats with peak absorption at 2-4 h post administration, as expected for fatty acids. The micronucleus assay showed no genotoxicity for fish oil containing VLCFAs. Together, the data shows that VLCFAs up to the test dose of 1200 mg/kg b.w. do not show genotoxicity.
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9
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Honzíková T, Agbaga MP, Anderson RE, Brush R, Ahmad M, Musílková L, Šejstalová K, Alishevich K, Beneš R, Šimicová P, Berčíková M, Filip V, Kyselka J. Novel Approaches for Elongation of Fish Oils into Very-Long-Chain Polyunsaturated Fatty Acids and Their Enzymatic Interesterification into Glycerolipids. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:17909-17923. [PMID: 37947776 PMCID: PMC10682991 DOI: 10.1021/acs.jafc.3c05355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/13/2023] [Accepted: 10/20/2023] [Indexed: 11/12/2023]
Abstract
Elongation of the Very-Long-Chain Fatty Acids-4 (ELOVL4) enzyme that is expressed in neuronal tissues, sperm, and testes mediates biosynthesis of very-long-chain polyunsaturated fatty acids (VLC-PUFAs) from dietary long chain PUFAs (LC-PUFAs). The VLC-PUFAs are critical for neuronal and reproductive function. Therefore, mutations in ELOVL4 that affect VLC-PUFA biosynthesis contribute to retinal degenerative diseases including Autosomal Dominant Stargardt-like Macular Dystrophy (STGD3). Recent studies have also shown not only a depletion of retinal VLC-PUFAs with normal aging but also a more significant loss of VLC-PUFAs in donor eyes of patients with age-related macular degeneration (AMD). However, currently, there are no natural sources of VLC-PUFAs to be evaluated as dietary supplements for the attenuation of retinal degeneration in animal models of STGD3. Here, we report the development of a novel chemical approach for elongation of eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids from fish oils by 6 carbon atoms to make a unique group of VLC-PUFAs, namely all-cis-hexacosa-11,14,17,20,23-pentaenoic acids (C26:5 n-3) and all-cis-octacosa-10,13,16,19,22,25-hexaenoic acids (C28:6 n-3). The three-step elongation approach that we report herein resulted in a good overall yield of up to 20.2%. This more sustainable approach also resulted in improved functional group compatibility and minimal impact on the geometrical integrity of the all-cis double bond system of the VLC-PUFAs. In addition, we also successfully used commercial deep-sea fish oil concentrate as an inexpensive material for the C6 elongation of fish oil LC-PUFAs into VLC-PUFAs, which resulted in the making of gram scales of VLC-PUFAs with an even higher isolation yield of 31.0%. The quality of fish oils and the content of oxidized lipids were key since both strongly affected the activity of the PEPPSI-IPr catalyst and ultimately the yield of coupling reactions. Downstream enzymatic interesterification was used for the first time to prepare structured glycerolipids enriched with VLC-PUFAs that could be evaluated in vivo to determine absorption and transport to target tissues relative to those of the free fatty acid forms. It turned out that in the synthesis of structured triacylglycerols and glycerophospholipids with VLC-PUFAs, the polarity of the immobilized lipase carrier and its humidity were essential.
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Affiliation(s)
- Tereza Honzíková
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
| | - Martin-Paul Agbaga
- Departments of Cell Biology & Ophthalmology,
Dean McGee Eye Institute, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Robert Eugene Anderson
- Departments of Cell Biology & Ophthalmology,
Dean McGee Eye Institute, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Richard Brush
- Departments of Cell Biology & Ophthalmology,
Dean McGee Eye Institute, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Mohiuddin Ahmad
- Departments of Cell Biology & Ophthalmology,
Dean McGee Eye Institute, University of
Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Lenka Musílková
- The
Department of Chemistry of Natural Compounds, Faculty of Food and
Biochemical Technology, University of Chemistry
and Technology, Technická
5, 166 28 Prague, Czechia
| | - Karolína Šejstalová
- The
Department of Chemistry of Natural Compounds, Faculty of Food and
Biochemical Technology, University of Chemistry
and Technology, Technická
5, 166 28 Prague, Czechia
| | - Katsiaryna Alishevich
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
| | - Radek Beneš
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
| | - Petra Šimicová
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
| | - Markéta Berčíková
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
| | - Vladimír Filip
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
| | - Jan Kyselka
- Department
of Dairy, Fat and Cosmetics, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague, Czechia
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10
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Gao F, Tom E, Lieffrig SA, Finnemann SC, Skowronska-Krawczyk D. A novel quantification method for retinal pigment epithelium phagocytosis using a very-long-chain polyunsaturated fatty acids-based strategy. Front Mol Neurosci 2023; 16:1279457. [PMID: 37928068 PMCID: PMC10622967 DOI: 10.3389/fnmol.2023.1279457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/10/2023] [Indexed: 11/07/2023] Open
Abstract
Introduction The vertebrate retinal pigment epithelium (RPE) lies adjacent to the photoreceptors and is responsible for the engulfment and degradation of shed photoreceptor outer segment fragments (POS) through receptor-mediated phagocytosis. Phagocytosis of POS is critical for maintaining photoreceptor function and is a key indicator of RPE functionality. Popular established methods to assess RPE phagocytosis rely mainly on quantifying POS proteins, especially their most abundant protein rhodopsin, or on fluorescent dye conjugation of bulk, unspecified POS components. While these approaches are practical and quantitative, they fail to assess the fate of POS lipids, which make up about 50% of POS by dry weight and whose processing is essential for life-long functionality of RPE and retina. Methods We have developed a novel very-long-chain polyunsaturated fatty acids (VLC-PUFA)-based approach for evaluating RPE phagocytic activity by primary bovine and rat RPE and the human ARPE-19 cell line and validated its results using traditional methods. Results and discussion This new approach can be used to detect in vitro the dynamic process of phagocytosis at varying POS concentrations and incubation times and offers a robust, unbiased, and reproducible assay that will have utility in studies of POS lipid processing.
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Affiliation(s)
- Fangyuan Gao
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, United States
| | - Emily Tom
- Department of Physiology and Biophysics, Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, United States
| | - Stephanie A. Lieffrig
- Center for Cancer, Genetic Diseases and Gene Regulation, Department of Biological Sciences, Fordham University, New York, NY, United States
| | - Silvia C. Finnemann
- Center for Cancer, Genetic Diseases and Gene Regulation, Department of Biological Sciences, Fordham University, New York, NY, United States
| | - Dorota Skowronska-Krawczyk
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, United States
- Department of Physiology and Biophysics, Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, United States
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11
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Ye S, Wang Z, Ma JH, Ji S, Peng Y, Huang Y, Chen J, Tang S. Diabetes Reshapes the Circadian Transcriptome Profile in Murine Retina. Invest Ophthalmol Vis Sci 2023; 64:3. [PMID: 37788001 PMCID: PMC10552875 DOI: 10.1167/iovs.64.13.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/09/2023] [Indexed: 10/04/2023] Open
Abstract
Purpose Diabetic retinopathy (DR) is a common complication of diabetes and has a high prevalence. Dysregulation of circadian rhythmicity is associated with the development of DR. This research aimed to investigate rhythmical transcriptome alterations in the retina of diabetic mice. Methods C57BL/6J mice were used to establish a diabetes model by intraperitoneal injection of streptozotocin (STZ). After 12 weeks, retinas were collected continuously at 4-hour intervals over 1 day. Total RNA was extracted from normal and STZ-treated retinas and RNA sequencing was performed. Meta2d algorithm, Kyoto Encyclopedia of Genes, Phase Set Enrichment Analysis, and time-series cluster analysis were used to identify, analyze and annotate the composition, phase, and molecular functions of rhythmic transcripts in retinas. Results The retina exhibited powerful transcriptome rhythmicity. STZ-induced diabetes markedly modified the transcriptome characteristics of the circadian transcriptome in the retina, including composition, phase, and amplitude. Moreover, the diabetic mice led to re-organized temporal and clustering enrichment pathways in space and time and affected core clock machinery. Conclusions Diabetes impairs the circadian rhythm of the transcriptomic profile of retinas. This study offers new perspectives on the negative effects of diabetes on the retina, which may provide important information for the development of new treatments for DR.
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Affiliation(s)
- Suna Ye
- AIER Eye Hospital, Jinan University, Guangzhou, China
- AIER Eye Institute, Changsha, China
| | | | | | | | | | | | - Jiansu Chen
- AIER Eye Hospital, Jinan University, Guangzhou, China
- AIER Eye Institute, Changsha, China
| | - Shibo Tang
- AIER Eye Hospital, Jinan University, Guangzhou, China
- AIER Eye Institute, Changsha, China
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12
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Gyening YK, Boris K, Cyril M, Brush RS, Nassogne MC, Agbaga MP. A novel ELOVL4 variant, L168S, causes early childhood-onset Spinocerebellar ataxia-34 and retinal dysfunction: a case report. Acta Neuropathol Commun 2023; 11:131. [PMID: 37568198 PMCID: PMC10416515 DOI: 10.1186/s40478-023-01628-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/22/2023] [Indexed: 08/13/2023] Open
Abstract
Spinocerebellar ataxia 34 (SCA34) is an autosomal dominant inherited disease characterized by age-related cerebellar degeneration and ataxia caused by mutations in the Elongation of Very Long Chain Fatty Acid-4 (ELOVL4) gene. The ELOVL4 enzyme catalyzes the biosynthesis of both very long chain saturated fatty acids (VLC-SFA) and very long chain polyunsaturated fatty acids (VLC-PUFA) that are important for neuronal, reproductive, and skin function. Several variants in ELOVL4 have been shown to cause different tissue-specific disorders including SCA34 with or without Erythrokeratodermia Variabilis (EKV), a skin condition characterized by dry, scaly skin, Autosomal Dominant Stargardt-Like Macular Dystrophy (STGD3), and seizures associated with neuro-ichthyotic disorders. What is puzzling is how different mutations in the same gene seem to cause different tissue-specific disorders. To date, no SCA34 patients have presented with both SCA34 and STGD3 pathology that is caused by ELOVL4 variants that cause truncation of ELOVL4. Here, we report a novel case of an early childhood onset and rapidly progressive cerebellar degeneration and retinal dysfunction in a Belgian-Italian girl who developed severe dysarthria and gait problems starting at about 3.5 years of age and progressed to immobility by 4.5 years of age. Brain magnetic resonance imaging (MRI) revealed progressive vermian, cerebellar, cortical atrophy, progressive corpus callosum slimming, and hot cross bun sign visible on the MRI. Ophthalmological examinations also revealed progressive macular dysfunction as measured by electroretinography. Using exome sequencing, we identified a novel heterozygous ELOVL4 variant, c.503 T > C (p. L168S) in the patient. To understand the enzymatic function of this novel ELOVL4 variant and how it alters the levels of VLC-PUFA and VLC-SFA biosynthesis to contribute to cerebellar and retinal dysfunction, we expressed wild-type ELOVL4 or the L168S ELOVL4 variant in cell culture and supplemented the cultures with VLC-PUFA or VLC-SFA precursors. We showed that the L168S ELOVL4 variant is deficient in the biosynthesis of VLC-SFA and VLC-PUFA. Our work suggests that differential depletion of these fatty acids may be a contributing factor to the pathogenic mechanism of SCA34 with or without EKV. Further studies will help further define how the different ELOVL4 variants cause different tissue-specific disorders with variable ages of onset.
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Affiliation(s)
- Yeboah Kofi Gyening
- Department of Cell Biology, University of Oklahoma Health Sciences Center, DMEI 423 Parke Pavilion, 608 Stanton L. Young Boulevard, Oklahoma City, OK, 73104, USA
- Department of Ophthalmology and Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, USA
- Unité Déficiences Intellectuelles/Troubles du, Développement, Service de Génétique Clinique et Médicale, AP-HP. Sorbonne Université -Hôpital de La Pitié-Salpêtrière, Paris, France
| | - Keren Boris
- UF de Génomique du Développement, Centre de Génétique Moléculaire et Chromosomique, AP-HP.Sorbonne Université - Hôpital de La Pitié-Salpêtrière, Paris, France
- Unité Déficiences Intellectuelles/Troubles du, Développement, Service de Génétique Clinique et Médicale, AP-HP. Sorbonne Université -Hôpital de La Pitié-Salpêtrière, Paris, France
| | - Mignot Cyril
- Unité Déficiences Intellectuelles/Troubles du, Développement, Service de Génétique Clinique et Médicale, AP-HP. Sorbonne Université -Hôpital de La Pitié-Salpêtrière, Paris, France
- Centre de Référence des Maladies Héréditaires du Métabolisme - Service de NeurologiePédiatrique, Cliniques Universitaires Saint-Luc -UCLouvain, Avenue Hippocrate, 10, 1200, Brussels, Belgium
| | - Richard S Brush
- Department of Cell Biology, University of Oklahoma Health Sciences Center, DMEI 423 Parke Pavilion, 608 Stanton L. Young Boulevard, Oklahoma City, OK, 73104, USA
- Department of Ophthalmology and Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, USA
- Unité Déficiences Intellectuelles/Troubles du, Développement, Service de Génétique Clinique et Médicale, AP-HP. Sorbonne Université -Hôpital de La Pitié-Salpêtrière, Paris, France
| | - Marie-Cécile Nassogne
- Centre de Référence des Maladies Héréditaires du Métabolisme - Service de NeurologiePédiatrique, Cliniques Universitaires Saint-Luc -UCLouvain, Avenue Hippocrate, 10, 1200, Brussels, Belgium.
| | - Martin-Paul Agbaga
- Department of Cell Biology, University of Oklahoma Health Sciences Center, DMEI 423 Parke Pavilion, 608 Stanton L. Young Boulevard, Oklahoma City, OK, 73104, USA.
- Department of Ophthalmology and Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
- Unité Déficiences Intellectuelles/Troubles du, Développement, Service de Génétique Clinique et Médicale, AP-HP. Sorbonne Université -Hôpital de La Pitié-Salpêtrière, Paris, France.
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13
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Nwagbo U, Bernstein PS. Understanding the Roles of Very-Long-Chain Polyunsaturated Fatty Acids (VLC-PUFAs) in Eye Health. Nutrients 2023; 15:3096. [PMID: 37513514 PMCID: PMC10383069 DOI: 10.3390/nu15143096] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 07/06/2023] [Accepted: 07/08/2023] [Indexed: 07/30/2023] Open
Abstract
Lipids serve many roles in the neural system, from synaptic stabilization and signaling to DNA regulation and neuroprotection. They also regulate inflammatory responses, maintain cellular membrane structure, and regulate the homeostatic balance of ions and signaling molecules. An imbalance of lipid subgroups is implicated in the progression of many retinal diseases, such as age-related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy, and diet can play a key role in influencing these diseases' onset, progression, and severity. A special class of lipids termed very-long-chain polyunsaturated fatty acids (VLC-PUFAs) is found exclusively in mammalian vertebrate retinas and a few other tissues. They comprise <2% of fatty acids in the retina and are depleted in the retinas of patients with diseases like diabetic retinopathy and AMD. However, the implications of the reduction in VLC-PUFA levels are poorly understood. Dietary supplementation studies and ELOVL4 transgene studies have had positive outcomes. However, much remains to be understood about their role in retinal health and the potential for targeted therapies against retinal disease.
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Affiliation(s)
- Uzoamaka Nwagbo
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT 84132, USA;
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Paul S. Bernstein
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT 84132, USA;
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
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14
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Inague A, Alecrim LC, Monteiro JS, Yoshinaga MY, Setubal JC, Miyamoto S, Giordano RJ. Oxygen-induced pathological angiogenesis promotes intense lipid synthesis and remodeling in the retina. iScience 2023; 26:106777. [PMID: 37213234 PMCID: PMC10199268 DOI: 10.1016/j.isci.2023.106777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/26/2023] [Accepted: 04/25/2023] [Indexed: 05/23/2023] Open
Abstract
The retina is a notable tissue with high metabolic needs which relies on specialized vascular networks to protect the neural retina while maintaining constant supplies of oxygen, nutrients, and dietary essential fatty acids. Here we analyzed the lipidome of the mouse retina under healthy and pathological angiogenesis using the oxygen-induced retinopathy model. By matching lipid profiles to changes in mRNA transcriptome, we identified a lipid signature showing that pathological angiogenesis leads to intense lipid remodeling favoring pathways for neutral lipid synthesis, cholesterol import/export, and lipid droplet formation. Noteworthy, it also shows profound changes in pathways for long-chain fatty acid production, vital for retina homeostasis. The net result is accumulation of large quantities of mead acid, a marker of essential fatty acid deficiency, and a potential marker for retinopathy severity. Thus, our lipid signature might contribute to better understand diseases of the retina that lead to vision impairment or blindness.
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Affiliation(s)
- Alex Inague
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Lilian Costa Alecrim
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Jhonatas Sirino Monteiro
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Marcos Yukio Yoshinaga
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - João Carlos Setubal
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Sayuri Miyamoto
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
- Corresponding author
| | - Ricardo José Giordano
- Biochemistry Department, Institute of Chemistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
- Corresponding author
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15
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Protocol and Methods Applicable to Retinal Vascular Diseases. Methods Mol Biol 2023; 2625:71-78. [PMID: 36653633 DOI: 10.1007/978-1-0716-2966-6_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Lipidomics is a branch of omics biology that enables the characterization and determination of different lipid classes. Mass spectrometry is a widely used tool to identify and obtain qualitative and quantitative measurements of the range of lipid species in various cell/tissue types. Human retina is highly rich in different classes of lipids that are liable to undergo modification such as oxidation, isomerization, peroxidation, and hydroxylation due to continuous metabolic activity in response to light photons. Alterations in lipid metabolism are associated with retinal diseases such as age-related macular degeneration, diabetic retinopathy, and retinopathy of prematurity. However, a clear understanding on the type of lipids/alterations involved in these diseases is not established yet. The unavailability of suitable biological retinal tissue need for this research has prompted us to explore vitreous humor and tear film for studying lipidomic alterations in different ocular diseases. Subjecting the lipid extract to tandem mass spectrometry further gives qualitative and quantitative lipidome of the diseased tissue. While the mass spectrometry approaches for lipid profiling have been adequately described, the present chapter focusses on a simplified protocol for extracting sufficient lipids/metabolites from vitreous humor and tear samples obtained from patients and their subsequent mass spectrometry analysis.
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16
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Untargeted Analysis of Lipids Containing Very Long Chain Fatty Acids in Retina and Retinal Tight Junctions. Methods Mol Biol 2023; 2625:269-290. [PMID: 36653650 DOI: 10.1007/978-1-0716-2966-6_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Several recent studies suggest that C24-C38 very long chain fatty acids (VLCFA) play an important role in vision, and decreased levels of retina VLCFA have been associated with vision disorders including the onset and progression of diabetic retinopathy in animal models. Traditional methods for VLCFA analysis lack the sensitivity and specificity needed to enable detailed characterization of VLCFA incorporation into complex lipids in tissues and subcellular components. To assess whether decreased VLCFA in diabetic retina are directly implicated in diabetes-induced breakdown of the blood-retinal barrier, we demonstrated the utility of performing untargeted lipid analysis via Orbitrap high resolution/accurate mass MS and MS/MS-based shotgun lipidomics to identify structural lipids containing VLCFA substituents. This comprehensive and highly sensitive approach to untargeted lipid identification enabled us to characterize low-abundance sphingolipids containing very long chain fatty acids from isolated retinal tight junction complexes, as well as VLCFA-containing phospholipids in retinal tissues. To facilitate future biochemical and physiological studies of the roles of VLCFA in blood-retina barrier integrity and maintenance of vision, this chapter describes steps to isolate tight junction complexes from a cell culture model of the outer blood-retinal barrier and perform untargeted Orbitrap high resolution/accurate mass-based lipid analysis to identify VLCFA in tight junctions and retina tissue.
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17
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Gyening YK, Chauhan NK, Tytanic M, Ea V, Brush RS, Agbaga MP. ELOVL4 Mutations That Cause Spinocerebellar Ataxia-34 Differentially Alter Very Long Chain Fatty Acid Biosynthesis. J Lipid Res 2023; 64:100317. [PMID: 36464075 PMCID: PMC9823237 DOI: 10.1016/j.jlr.2022.100317] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/28/2022] [Accepted: 11/17/2022] [Indexed: 12/03/2022] Open
Abstract
The FA Elongase-4 (ELOVL4) enzyme mediates biosynthesis of both very long chain (VLC)-PUFAs and VLC-saturated FA (VLC-SFAs). VLC-PUFAs play critical roles in retina and sperm function, whereas VLC-SFAs are predominantly associated with brain function and maintenance of the skin permeability barrier. While some ELOVL4 mutations cause Autosomal Dominant Stargardt-like Macular Dystrophy (STGD3), other ELOVL4 point mutations, such as L168F and W246G, affect the brain and/or skin, leading to Spinocerebellar Ataxia-34 (SCA34) and Erythrokeratodermia variabilis. The mechanisms by which these ELOVL4 mutations alter VLC-PUFA and VLC-SFA biosynthesis to cause the different tissue-specific pathologies are not well understood. To understand how these mutations alter VLC-PUFA and VLC-SFA biosynthesis, we expressed WT-ELOVL4, L168F, and W246G ELOVL4 variants in cell culture and supplemented the cultures with VLC-PUFA or VLC-SFA precursors. Total lipids were extracted, converted to FA methyl esters, and quantified by gas chromatography. We showed that L168F and W246G mutants were capable of VLC-PUFA biosynthesis. W246G synthesized and accumulated 32:6n3, while L168F exhibited gain of function in VLC-PUFA biosynthesis as it made 38:5n3, which we did not detect in WT-ELOVL4 or W246G-expressing cells. However, compared with WT-ELOVL4, both L168F and W246G mutants were deficient in VLC-SFA biosynthesis, especially the W246G protein, which showed negligible VLC-SFA biosynthesis. These results suggest VLC-PUFA biosynthetic capabilities of L168F and W246G in the retina, which may explain the lack of retinal phenotype in SCA34. Defects in VLC-SFA biosynthesis by these variants may be a contributing factor to the pathogenic mechanism of SCA34 and Erythrokeratodermia variabilis.
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Affiliation(s)
- Yeboah Kofi Gyening
- Departments of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Oklahoma, USA
| | - Neeraj Kumar Chauhan
- Departments of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Oklahoma, USA
| | - Madison Tytanic
- Departments of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Oklahoma, USA
| | - Vicki Ea
- Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Oklahoma, USA
| | - Richard S Brush
- Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Oklahoma, USA; Departments of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Martin-Paul Agbaga
- Departments of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Oklahoma, USA; Departments of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
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18
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Gorusupudi A, Nwagbo U, Bernstein PS. Role of VLC-PUFAs in Retinal and Macular Degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:257-261. [PMID: 37440042 DOI: 10.1007/978-3-031-27681-1_37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Very-long-chain polyunsaturated fatty acids (VLC-PUFAs) are a special class of fatty acids that are present in the retina and a few other human tissues. They cannot be synthesized de novo and are rarely present in dietary sources. Structurally, these lipids are composed of a proximal end with a typical saturated fatty acid character and a distal end more characteristic of common PUFAs. They have not been studied in detail until recently due to their low abundance in these tissues and technical difficulties in assaying these lipids by conventional chromatography. This unique class of lipids has chain lengths greater than 24 carbons, with the longest typically 38 carbons long. There is increasing interest in understanding their roles in the maintenance of retinal membrane integrity and the prevention of macular degeneration and inherited retinal diseases.
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Affiliation(s)
- Aruna Gorusupudi
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Uzoamaka Nwagbo
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Paul S Bernstein
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT, USA.
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19
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Cheng V, Rallabandi R, Gorusupudi A, Lucas S, Rognon G, Bernstein PS, Rainier JD, Conboy JC. Influence of very-long-chain polyunsaturated fatty acids on membrane structure and dynamics. Biophys J 2022; 121:2730-2741. [PMID: 35711144 PMCID: PMC9382336 DOI: 10.1016/j.bpj.2022.06.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/24/2022] [Accepted: 06/10/2022] [Indexed: 11/30/2022] Open
Abstract
The unique attributes of very-long-chain polyunsaturated fatty acids (VLC-PUFAs), their long carbon chains (n > 24) and high degree of unsaturation, impart unique chemical and physical properties to this class of fatty acids. The changes imparted by VLC-PUFA 32:6 n-3 on lipid packing and the compression moduli of model membranes were evaluated from π-A isotherms of VLC-PUFA in 1,2-distearoyl-sn-3-glycero-phosphocholine (DSPC) lipid monolayers. To compare the attractive or repulsive forces between VLC-PUFA and DSPC lipid monolayers, the measured mean molecular areas (MMAs) were compared with the calculated MMAs of an ideal mixture of VLC-PUFA and DSPC. The presence of 0.1, 1, and 10 mol % VLC-PUFA shifted the π-A isotherm to higher MMAs of the lipids comprising the membrane and the observed positive deviations from ideal behavior of the mixed VLC-PUFA:DSPC monolayers correspond to repulsive forces between VLC-PUFAs and DSPC. The MMA of the VLC-PUFA component was estimated using the measured MMAs of DSPC of 47.1 ± 0.7 Å2/molecule, to be 15,000, 1100, and 91 Å2/molecule at 0.1, 1, and 10 mol % VLC-PUFA:DSPC mixtures, respectively. The large MMAs of VLC-PUFA suggest that the docosahexaenoic acid tail reinserts into the membrane and adopts a nonlinear structure in the membrane, which is most pronounced at 0.1 mol % VLC-PUFA. The presence of 0.1 mol % VLC-PUFA:DSPC also significantly increased the compression modulus of the membrane by 28 mN/m compared with a pure DSPC membrane. The influence of VLC-PUFA on lipid "flip-flop" was investigated by sum-frequency vibrational spectroscopy. The incorporation of 0.1 mol % VLC-PUFA increased the DSPC flip-flop rate fourfold. The fact that VLC-PUFA promotes lipid translocation is noteworthy as retinal membranes require a high influx of retinoids which may be facilitated by lipid flip-flop.
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Affiliation(s)
- Victoria Cheng
- Department of Chemistry, University of Utah, Salt Lake City, Utah
| | | | - Aruna Gorusupudi
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah
| | - Steven Lucas
- Department of Chemistry, University of Utah, Salt Lake City, Utah
| | - Gregory Rognon
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah
| | - Paul S Bernstein
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah
| | - Jon D Rainier
- Department of Chemistry, University of Utah, Salt Lake City, Utah
| | - John C Conboy
- Department of Chemistry, University of Utah, Salt Lake City, Utah.
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20
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Kyselová L, Vítová M, Řezanka T. Very long chain fatty acids. Prog Lipid Res 2022; 87:101180. [PMID: 35810824 DOI: 10.1016/j.plipres.2022.101180] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/21/2022] [Accepted: 07/04/2022] [Indexed: 11/26/2022]
Abstract
Very long chain fatty acids (VLCFAs) are important components of various lipid classes in most organisms, from bacteria to higher plants and mammals, including humans. VLCFAs, or very long chain polyunsaturated fatty acids (VLCPUFAs), can be defined as fatty acids with 23 or more carbon atoms in the molecule. The main emphasis in this review is on the analysis of these acids, including obtaining standards from natural sources or their synthesis. Furthermore, the occurrence and analysis of these compounds in both lower (bacteria, invertebrates) and higher organisms (flowering plants or mammals) are discussed in detail. Attention is paid to their biosynthesis, especially the elongation of very long chain fatty acids protein (ELOVL4). This review deals with papers describing these very interesting compounds, whose chemical, biochemical and biological properties have not been fully explored.
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Affiliation(s)
- Lucie Kyselová
- Research Institute of Brewing and Malting, Lípová 511, 120 44 Prague, Czech Republic.
| | - Milada Vítová
- Institute of Botany, Czech Academy of Sciences, Centre for Phycology, Dukelská 135, 379 01 Třeboň, Czech Republic.
| | - Tomáš Řezanka
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
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21
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Lewandowski D, Sander CL, Tworak A, Gao F, Xu Q, Skowronska-Krawczyk D. Dynamic lipid turnover in photoreceptors and retinal pigment epithelium throughout life. Prog Retin Eye Res 2022; 89:101037. [PMID: 34971765 PMCID: PMC10361839 DOI: 10.1016/j.preteyeres.2021.101037] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/13/2021] [Accepted: 12/15/2021] [Indexed: 12/13/2022]
Abstract
The retinal pigment epithelium-photoreceptor interphase is renewed each day in a stunning display of cellular interdependence. While photoreceptors use photosensitive pigments to convert light into electrical signals, the RPE supports photoreceptors in their function by phagocytizing shed photoreceptor tips, regulating the blood retina barrier, and modulating inflammatory responses, as well as regenerating the 11-cis-retinal chromophore via the classical visual cycle. These processes involve multiple protein complexes, tightly regulated ligand-receptors interactions, and a plethora of lipids and protein-lipids interactions. The role of lipids in maintaining a healthy interplay between the RPE and photoreceptors has not been fully delineated. In recent years, novel technologies have resulted in major advancements in understanding several facets of this interplay, including the involvement of lipids in phagocytosis and phagolysosome function, nutrient recycling, and the metabolic dependence between the two cell types. In this review, we aim to integrate the complex role of lipids in photoreceptor and RPE function, emphasizing the dynamic exchange between the cells as well as discuss how these processes are affected in aging and retinal diseases.
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Affiliation(s)
- Dominik Lewandowski
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA
| | - Christopher L Sander
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA; Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Aleksander Tworak
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA
| | - Fangyuan Gao
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA
| | - Qianlan Xu
- Department of Physiology and Biophysics, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA
| | - Dorota Skowronska-Krawczyk
- Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA; Department of Physiology and Biophysics, Center for Translational Vision Research, School of Medicine, UC Irvine, Irvine, CA, USA.
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22
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Bernstein PS. Nourishing Better Vision: The ARVO 2021 Mildred Weisenfeld Award Lecture. Invest Ophthalmol Vis Sci 2022; 63:13. [PMID: 35285848 PMCID: PMC8934560 DOI: 10.1167/iovs.63.3.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
- Paul S Bernstein
- Moran Eye Center, University of Utah, Salt Lake City, Utah, United States
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23
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Sander CL, Sears AE, Pinto AF, Choi EH, Kahremany S, Gao F, Salom D, Jin H, Pardon E, Suh S, Dong Z, Steyaert J, Saghatelian A, Skowronska-Krawczyk D, Kiser PD, Palczewski K. Nano-scale resolution of native retinal rod disk membranes reveals differences in lipid composition. J Cell Biol 2021; 220:e202101063. [PMID: 34132745 PMCID: PMC8240855 DOI: 10.1083/jcb.202101063] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 04/26/2021] [Accepted: 05/18/2021] [Indexed: 02/07/2023] Open
Abstract
Photoreceptors rely on distinct membrane compartments to support their specialized function. Unlike protein localization, identification of critical differences in membrane content has not yet been expanded to lipids, due to the difficulty of isolating domain-specific samples. We have overcome this by using SMA to coimmunopurify membrane proteins and their native lipids from two regions of photoreceptor ROS disks. Each sample's copurified lipids were subjected to untargeted lipidomic and fatty acid analysis. Extensive differences between center (rhodopsin) and rim (ABCA4 and PRPH2/ROM1) samples included a lower PC to PE ratio and increased LC- and VLC-PUFAs in the center relative to the rim region, which was enriched in shorter, saturated FAs. The comparatively few differences between the two rim samples likely reflect specific protein-lipid interactions. High-resolution profiling of the ROS disk lipid composition gives new insights into how intricate membrane structure and protein activity are balanced within the ROS, and provides a model for future studies of other complex cellular structures.
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Affiliation(s)
- Christopher L. Sander
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Avery E. Sears
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Antonio F.M. Pinto
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA
| | - Elliot H. Choi
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Shirin Kahremany
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Fangyuan Gao
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - David Salom
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Hui Jin
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
| | - Els Pardon
- Vlaams Instituut voor Biotechnologie–Vrije Universiteit Brussel Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - Susie Suh
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Zhiqian Dong
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Jan Steyaert
- Vlaams Instituut voor Biotechnologie–Vrije Universiteit Brussel Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - Alan Saghatelian
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA
| | - Dorota Skowronska-Krawczyk
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA
| | - Philip D. Kiser
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA
- Research Service, VA Long Beach Healthcare System, Long Beach, CA
| | - Krzysztof Palczewski
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA
- Department of Chemistry, University of California, Irvine, Irvine, CA
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24
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Wade A, Rallabandi R, Lucas S, Oberg C, Gorusupudi A, Bernstein PS, Rainier JD. The synthesis of the very long chain polyunsaturated fatty acid (VLC-PUFA) 32:6 n-3. Org Biomol Chem 2021; 19:5563-5566. [PMID: 34080605 DOI: 10.1039/d1ob00491c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This article describes the synthesis of VLC-PUFA 32:6 n-3, D2-labeled 32:6 n-3, and the uptake of 32:6 n-3 into mouse retinal tissue.
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Affiliation(s)
- Alexander Wade
- Department of Chemistry, University of Utah, 315 South, 1400 East, Salt Lake City, UT 84112, USA.
| | - Rameshu Rallabandi
- Department of Chemistry, University of Utah, 315 South, 1400 East, Salt Lake City, UT 84112, USA.
| | - Steven Lucas
- Department of Chemistry, University of Utah, 315 South, 1400 East, Salt Lake City, UT 84112, USA.
| | - Catrina Oberg
- Department of Chemistry, University of Utah, 315 South, 1400 East, Salt Lake City, UT 84112, USA.
| | - Aruna Gorusupudi
- Department of Ophthalmology and Visual Sciences, 65 Mario Capecchi Drive, Moran Eye Center, University of Utah, Salt Lake City, UT 84132, USA
| | - Paul S Bernstein
- Department of Ophthalmology and Visual Sciences, 65 Mario Capecchi Drive, Moran Eye Center, University of Utah, Salt Lake City, UT 84132, USA
| | - Jon D Rainier
- Department of Chemistry, University of Utah, 315 South, 1400 East, Salt Lake City, UT 84112, USA.
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