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Aarnio R, Kirjavainen A, Rajander J, Forsback S, Kalliokoski K, Nuutila P, Milicevic Z, Coskun T, Haupt A, Laitinen I, Haaparanta-Solin M. New improved radiometabolite analysis method for [ 18F]FTHA from human plasma: a test-retest study with postprandial and fasting state. EJNMMI Res 2024; 14:53. [PMID: 38869780 DOI: 10.1186/s13550-024-01114-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Accepted: 05/28/2024] [Indexed: 06/14/2024] Open
Abstract
BACKGROUND Fatty acid uptake can be measured using PET and 14-(R,S)-[18F]fluoro-6-thia-heptadecanoic acid ([18F]FTHA). However, the relatively rapid rate of [18F]FTHA metabolism significantly affects kinetic modeling of tissue uptake. Thus, there is a need for accurate chromatographic methods to analyze the unmetabolized [18F]FTHA (parent fraction). Here we present a new radiometabolite analysis (RMA) method, with comparison to a previous method for parent fraction analysis, and its use in a test-retest clinical study under fasting and postprandial conditions. We developed a new thin-layer chromatography (TLC) RMA method for analysis of [18F]FTHA parent fraction and its radiometabolites from plasma, by testing stationary phases and eluent combinations. Next, we analyzed [18F]FTHA, its radiometabolites, and plasma radioactivity from subjects participating in a clinical study. A total of 17 obese or overweight participants were dosed with [18F]FTHA twice under fasting, and twice under postprandial conditions and plasma samples were obtained between 14 min (mean of first sample) and 72 min (mean of last sample) post-injection. Aliquots of 70 plasma samples were analyzed using both methods, enabling head-to-head comparisons. We performed test-retest and group comparisons of the parent fraction and plasma radioactivity. RESULTS The new TLC method separated seven [18F]FTHA radiometabolite peaks, while the previous method separated three. The new method revealed at least one radiometabolite that was not previously separable from [18F]FTHA. From the plasma samples, the mean parent fraction value was on average 7.2 percentage points lower with the new method, compared to the previous method. Repeated [18F]FTHA investigations on the same subject revealed reproducible plasma SUV and parent fractions, with different kinetics between the fasted and postprandial conditions. CONCLUSIONS The newly developed improved radio-TLC method for [18F]FTHA RMA enables accurate parent fraction correction, which is required to obtain quantitative data for modelling [18F]FTHA PET data. Our test-retest study of fasted and postprandial conditions showed robust reproducibility, and revealed clear differences in the [18F]FTHA metabolic rate under different study settings. TRIAL REGISTRATION EudraCT No: 2020-005211-48, 04Feb2021; and Clinical Trials registry NCT05132335, 29Oct2021, URL: https://classic. CLINICALTRIALS gov/ct2/show/NCT05132335 .
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Affiliation(s)
- Richard Aarnio
- MediCity Research Laboratory, University of Turku, Turku, Finland.
- Drug Research Doctoral Programme, University of Turku, Turku, Finland.
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, Turku, FI-20520, Finland.
| | - Anna Kirjavainen
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, Turku, FI-20520, Finland
| | - Johan Rajander
- Accelerator Laboratory, Turku PET Centre, Åbo Akademi University, Turku, Finland
| | - Sarita Forsback
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, Turku, FI-20520, Finland
| | - Kari Kalliokoski
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, Turku, FI-20520, Finland
| | - Pirjo Nuutila
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, Turku, FI-20520, Finland
- Department of Endocrinology, Turku University Hospital, Turku, Finland
| | | | | | - Axel Haupt
- Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Merja Haaparanta-Solin
- MediCity Research Laboratory, University of Turku, Turku, Finland
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, Turku, FI-20520, Finland
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Klievik BJ, Tyrrell AD, Chen CT, Bazinet RP. Measuring brain docosahexaenoic acid turnover as a marker of metabolic consumption. Pharmacol Ther 2023:108437. [PMID: 37201738 DOI: 10.1016/j.pharmthera.2023.108437] [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: 02/21/2023] [Revised: 05/02/2023] [Accepted: 05/15/2023] [Indexed: 05/20/2023]
Abstract
Docosahexaenoic acid (DHA, 22:6n-3) accretion in brain phospholipids is critical for maintaining the structural fluidity that permits proper assembly of protein complexes for signaling. Furthermore, membrane DHA can by released by phospholipase A2 and act as substrate for synthesis of bioactive metabolites that regulate synaptogenesis, neurogenesis, inflammation, and oxidative stress. Thus, brain DHA is consumed through multiple pathways including mitochondrial β-oxidation, autoxidation to neuroprostanes, as well as enzymatic synthesis of bioactive metabolites including oxylipins, synaptamide, fatty-acid amides, and epoxides. By using models developed by Rapoport and colleagues, brain DHA loss has been estimated to be 0.07-0.26 μmol DHA/g brain/d. Since β-oxidation of DHA in the brain is relatively low, a large portion of brain DHA loss may be attributed to synthesis of autoxidative and bioactive metabolites. In recent years, we have developed a novel application of compound specific isotope analysis to trace DHA metabolism. By the use of natural abundance in 13C-DHA in food supply, we are able to trace brain phospholipid DHA loss in free-living mice with estimates ranging from 0.11 to 0.38 μmol DHA/g brain/d, in reasonable agreement with previous methods. This novel fatty acid metabolic tracing methodology should improve our understanding of the factors that regulate brain DHA metabolism.
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Affiliation(s)
- Brinley J Klievik
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8
| | - Aidan D Tyrrell
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8
| | - Chuck T Chen
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8
| | - Richard P Bazinet
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
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Klievik BJ, Metherel AH, Cisbani G, Valenzuela R, Bazinet RP. Novel 13C enrichment technique reveals early turnover of DHA in peripheral tissues. J Lipid Res 2023; 64:100357. [PMID: 36948271 PMCID: PMC10154972 DOI: 10.1016/j.jlr.2023.100357] [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: 01/28/2023] [Revised: 03/05/2023] [Accepted: 03/14/2023] [Indexed: 03/24/2023] Open
Abstract
The brain is rich in DHA, which plays important roles in regulating neuronal function. Recently, using compound-specific isotope analysis (CSIA) that takes advantage of natural differences in carbon-13 content (13C/12C ratio or δ13C) of the food supply, we determined the brain DHA half-life. However, due to methodological limitations, we were unable to capture DHA turnover rates in peripheral tissues. In the current study, we applied CSIA via high-precision gas chromatography combustion isotope ratio mass spectrometry (GC/C/IRMS) to determine half-lives of brain, liver, and plasma DHA in mice following a dietary switch experiment. To model DHA tissue turnover rates in peripheral tissues, we added earlier timepoints within the diet switch study and took advantage of natural variations in the δ13C-DHA of algal and fish DHA sources to maintain DHA pool sizes and used an enriched (uniformly labeled 13C) DHA treatment. Mice were fed a fish-DHA diet (control) for 3 months, then switched to an algal-DHA treatment diet, the 13C enriched-DHA treatment diet, or they stayed on the control diet for the remainder of the study time course. In mice fed the algal and 13C enriched-DHA diets, the brain DHA half-life was 47 and 46 days, the liver half-life was 5.6 and 7.2 days, and the plasma half-life was 4.7 and 6.4 days respectively. By using improved methodologies, we calculated DHA turnover rates in the liver and plasma, and our study for the first time, by using an artificially enriched DHA source (very high δ13C), validated its utility in diet switch studies.
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Affiliation(s)
- Brinley J Klievik
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8
| | - Adam H Metherel
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8
| | - Giulia Cisbani
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8
| | - Rodrigo Valenzuela
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8
| | - Richard P Bazinet
- Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8.
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Rapoport SI. Aspirin and celecoxib may help to rectify a neurotransmission imbalance in bipolar disorder. Med Hypotheses 2021; 149:110536. [PMID: 33618245 DOI: 10.1016/j.mehy.2021.110536] [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: 01/21/2021] [Accepted: 02/10/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Mood stabilizers with disparate chemical structures are approved for treating bipolar disorder, but their mechanisms of action are not agreed on. However, when administered to unanesthetized rats at clinically relevant doses, they modulate neurotransmission involving arachidonic acid and brain activity of COX-2, which oxidizes arachidonic acid within the arachidonic acid metabolic cascade. HYPOTHESIS Inhibiting COX-2 directly might enhance mood stabilizer effects in bipolar disorder patients. OBSERVATIONS This paper reviews randomized controlled trials that showed that celecoxib, a selective COX-2 inhibitor, or low-dose aspirin, which inhibits COX-1 and inhibits/acetylates COX-2, reduced bipolar symptoms in patients on mood stabilizers. More convincing are two population based pharmacoepidemiological studies that each demonstrated that chronic low dose aspirin reduced bipolar severity markers in patients on mood stabilizers. CONCLUSIONS This clinical evidence is consistent with the hypothesis that low-dose chronic aspirin and celecoxib, which can inhibit COX-2 and enter brain, can be repurposed in bipolar disorder to enhance mood stabilizer effects on arachidonic acid metabolism and neurotransmission.
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Affiliation(s)
- Stanley I Rapoport
- Laboratory on Molecular Signaling, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, United States.
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Liu ZH, Huang YC, Kuo CY, Kuo CY, Chin CY, Yip PK, Chen JP. Docosahexaenoic Acid-Loaded Polylactic Acid Core-Shell Nanofiber Membranes for Regenerative Medicine after Spinal Cord Injury: In Vitro and In Vivo Study. Int J Mol Sci 2020; 21:ijms21197031. [PMID: 32987768 PMCID: PMC7583922 DOI: 10.3390/ijms21197031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 12/13/2022] Open
Abstract
Spinal cord injury (SCI) is associated with disability and a drastic decrease in quality of life for affected individuals. Previous studies support the idea that docosahexaenoic acid (DHA)-based pharmacological approach is a promising therapeutic strategy for the management of acute SCI. We postulated that a nanostructured material for controlled delivery of DHA at the lesion site may be well suited for this purpose. Toward this end, we prepare drug-loaded fibrous mats made of core-shell nanofibers by electrospinning, which contained a polylactic acid (PLA) shell for encapsulation of DHA within the core, for delivery of DHA in situ. In vitro study confirmed sustained DHA release from PLA/DHA core-shell nanofiber membrane (CSNM) for up to 36 days, which could significantly increase neurite outgrowth from primary cortical neurons in 3 days. This is supported by the upregulation of brain-derived neurotropic factor (BDNF) and neurotrophin-3 (NT-3) neural marker genes from qRT-PCR analysis. Most importantly, the sustained release of DHA could significantly increase the neurite outgrowth length from cortical neuron cells in 7 days when co-cultured with PLA/DHA CSNM, compared with cells cultured with 3 μM DHA. From in vivo study with a SCI model created in rats, implantation of PLA/DHA CSNM could significantly improve neurological functions revealed by behavior assessment in comparison with the control (no treatment) and the PLA CSNM groups. According to histological analysis, PLA/DHA CSNM also effectively reduced neuron loss and increased serotonergic nerve sprouting. Taken together, the PLA/DHA CSNM may provide a nanostructured drug delivery system for DHA and contribute to neuroprotection and promoting neuroplasticity change following SCI.
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Affiliation(s)
- Zhuo-Hao Liu
- Department of Neurosurgery, Chang Gung Memorial Hospital, Linkou, Chang Gung University School of Medicine, Kwei-San, Taoyuan 33305, Taiwan; (Z.-H.L.); (Y.-C.H.); (C.-Y.K.); (C.-Y.C.)
| | - Yin-Cheng Huang
- Department of Neurosurgery, Chang Gung Memorial Hospital, Linkou, Chang Gung University School of Medicine, Kwei-San, Taoyuan 33305, Taiwan; (Z.-H.L.); (Y.-C.H.); (C.-Y.K.); (C.-Y.C.)
| | - Chang-Yi Kuo
- Department of Chemical and Materials and Materials Engineering, Chang Gung University, Kwei-San, Taoyuan 33302, Taiwan;
| | - Chao-Ying Kuo
- Department of Neurosurgery, Chang Gung Memorial Hospital, Linkou, Chang Gung University School of Medicine, Kwei-San, Taoyuan 33305, Taiwan; (Z.-H.L.); (Y.-C.H.); (C.-Y.K.); (C.-Y.C.)
| | - Chieh-Yu Chin
- Department of Neurosurgery, Chang Gung Memorial Hospital, Linkou, Chang Gung University School of Medicine, Kwei-San, Taoyuan 33305, Taiwan; (Z.-H.L.); (Y.-C.H.); (C.-Y.K.); (C.-Y.C.)
| | - Ping K. Yip
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute, Centre for Neuroscience, Surgery & Trauma, London E1 2AT, UK;
| | - Jyh-Ping Chen
- Department of Chemical and Materials and Materials Engineering, Chang Gung University, Kwei-San, Taoyuan 33302, Taiwan;
- Department of Plastic and Reconstructive Surgery and Craniofacial Research Center, Chang Gung Memorial Hospital, Linkou, Kwei-San, Taoyuan 33305, Taiwan
- Research Center for Food and Cosmetic Safety, Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 33302, Taiwan
- Department of Materials Engineering, Ming Chi University of Technology, Tai-Shan, New Taipei City 24301, Taiwan
- Correspondence: ; Tel.: +886-3211-8800 (ext. 5298)
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Rapoport SI, Hibbeln JR. THERAPEUTIC TARGETING OF BRAIN ARACHIDONIC ACID CASCADE IN BIPOLAR DISORDER BY LOW DOSE ASPIRIN AND CELECOXIB. Prostaglandins Leukot Essent Fatty Acids 2020; 159:102118. [PMID: 32505122 DOI: 10.1016/j.plefa.2020.102118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 04/21/2020] [Accepted: 04/28/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Studies in unanesthetized rats suggest that mood stabilizers approved for treating bipolar disorder downregulate brain arachidonic acid (AA) metabolism. AA plays a role in neurotransmission and neuroinflammation, among other processes. Other drugs that reduce brain AA metabolism may add to mood stabilizer action. METHODS We reviewed randomized controlled trials (RCTs) and population studies to examine whether celecoxib, a selective cyclooxygenase (COX)-2 inhibitor, and acetylsalicylate (aspirin), a COX-1 and COX-2 inhibitor and acetylator, were useful in bipolar disorder patients on mood stabilizers. COX-1 and COX-2 metabolize AA to bioactive eicosanoids. RESULTS Celecoxib significantly enhanced mood stabilizer efficacy in two 6-week RCTs involving 86 manic bipolar inpatients, and in one 8-week RCT on 49 patients with treatment-resistant bipolar depression. With regard to aspirin, a Dutch pharmacoepidemiological study involving 5145 subjects taking lithium reported symptom reduction with added chronic low dose 30-80 mg/day aspirin, while a Danish study on 321,350 subjects taking chronic 75-150 mg/day aspirin found fewer manic episodes than in subjects not on aspirin. Finally, a recent 6-week RCT using low-dose aspirin and/or minocycline showed a specific positive effect of aspirin. CONCLUSIONS Efficacy of both celecoxib and aspirin as adjuncts to mood stabilizers in the treatment of bipolar disorder is consistent with the AA hypothesis for mood stabilizer action in that disorder.
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Affiliation(s)
- Stanley I Rapoport
- Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892.
| | - Joseph R Hibbeln
- Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892
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Loving BA, Bruce KD. Lipid and Lipoprotein Metabolism in Microglia. Front Physiol 2020; 11:393. [PMID: 32411016 PMCID: PMC7198855 DOI: 10.3389/fphys.2020.00393] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 04/02/2020] [Indexed: 12/25/2022] Open
Abstract
Microglia, once viewed as static bystanders with limited homeostatic functions, are now considered key players in the development of neuroinflammatory and neurodegenerative diseases. Microglial activation is a salient feature of neuroinflammation involving a dynamic process that generates multitudinous microglial phenotypes that can respond to a variety of situational cues in the central nervous system. Recently, a flurry of single cell RNA-sequencing studies have defined microglial phenotypes in unprecedented detail, and have highlighted robust changes in the expression of genes involved in lipid and lipoprotein metabolism. Increased expression of genes such as Apolipoprotein E (ApoE), Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) and Lipoprotein Lipase (LPL) in microglia during development, damage, and disease, suggest that increased lipid metabolism is needed to fuel protective cellular functions such as phagocytosis. This review describes our current understanding of lipid and lipoprotein metabolism in microglia, and highlights microglial lipid metabolism as a modifiable target for the treatment of neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis.
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Affiliation(s)
- Bailey A. Loving
- School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
| | - Kimberley D. Bruce
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
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Lacombe RJS, Lee CC, Bazinet RP. Turnover of brain DHA in mice is accurately determined by tracer-free natural abundance carbon isotope ratio analysis. J Lipid Res 2020; 61:116-126. [PMID: 31712249 PMCID: PMC6939594 DOI: 10.1194/jlr.d119000518] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Indexed: 01/04/2023] Open
Abstract
The brain is highly enriched in the long-chain omega-3 (n-3) PUFA DHA. Due to the limited capacity for local DHA synthesis in the brain, it relies on a continual supply from the circulation to replenish metabolized DHA. Previous studies investigating brain DHA turnover and metabolism have relied on isotope tracers to determine brain fatty acid kinetics; however, this approach is cumbersome and costly. We applied natural abundance carbon isotope ratio analysis via high-precision gas chromatography combustion isotope ratio mass spectrometry, without the use of labeled tracers, to determine the half-life of brain DHA in mice following a dietary switch experiment. Mice fed diets containing either α-linolenic acid (ALA) or DHA as the sole dietary n-3 PUFA were switched onto diets containing ALA, DHA, or ALA + DHA at 6 weeks of age, while control mice were maintained on their respective background diet. We measured brain DHA carbon isotope ratios (reported as δ13CDHA signatures) over a 168-day time course. Brain δ13CDHA signatures of control mice maintained on background diets over the time course were stable (P > 0.05). Brain δ13CDHA signatures of mice switched to the DHA or ALA + DHA diet from the ALA diet changed over time, yielding brain incorporation half-lives of 40 and 34 days, respectively. These half-lives determined by natural abundance carbon isotope ratio analysis were consistent with estimates from kinetic isotope tracer studies. Our results demonstrate the feasibility of natural abundance carbon isotope ratio analysis in the study of fatty acid metabolism without the use of isotopically labeled fatty acid tracers.
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Affiliation(s)
- R J Scott Lacombe
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Chi-Chiu Lee
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
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Swastika, Chaturvedi S, Kaul A, Hazari PP, Jha P, Pal S, Lal S, Singh B, Barthélémy P, Mishra AK. Evaluation of BBB permeable nucleolipid (NLDPU): A di-C15-ketalised palmitone appended uridine as neuro-tracer for SPECT. Int J Pharm 2019; 565:269-282. [DOI: 10.1016/j.ijpharm.2019.04.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 04/16/2019] [Accepted: 04/27/2019] [Indexed: 12/17/2022]
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Ting HC, Chen LT, Chen JY, Huang YL, Xin RC, Chan JF, Hsu YHH. Double bonds of unsaturated fatty acids differentially regulate mitochondrial cardiolipin remodeling. Lipids Health Dis 2019; 18:53. [PMID: 30764880 PMCID: PMC6376731 DOI: 10.1186/s12944-019-0990-y] [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: 12/21/2018] [Accepted: 01/28/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Supplemented fatty acids can incorporate into cardiolipin (CL) and affect its remodeling. The change in CL species may alter the mitochondrial membrane composition, potentially disturbing the mitochondrial structure and function during inflammation. METHOD To investigate the effect of the unsaturation of fatty acids on CL, we supplemented macrophage-like RAW264.7 cells with 18-carbon unsaturated fatty acids including oleic acid (OA, 18:1), linoleic acid (LA, 18:2), α-linolenic acid (ALA, 18:3), γ-linolenic acid (GLA, 18:3), and stearidonic acid (SDA, 18:4). Mitochondrial changes in CL were measured through mass spectrometry. RESULT Our data indicated that OA(18:1) was the most efficient fatty acid that incorporated into CL, forming symmetrical CL without fatty acid elongation and desaturation. In addition, LA(18:2) and ALA(18:3) were further elongated before incorporation, significantly increasing the number of double bonds and the chain length of CL. GLA and SDA were not optimal substrates for remodeling enzymes. The findings of RT-qPCR experiments revealed that none of these changes in CL occurred through the regulation of CL remodeling- or synthesis-related genes. The fatty acid desaturase and transportation genes-Fads2 and Cpt1a, respectively-were differentially regulated by the supplementation of five unsaturated 18-carbon fatty acids. CONCLUSIONS The process of fatty acid incorporation to CL was regulated by the fatty acid desaturation and transportation into mitochondria in macrophage. The double bonds of fatty acids significantly affect the incorporation process and preference. Intact OA(18:1) was incorporated to CL; LA(18:2) and ALA(18:3) were desaturated and elongated to long chain fatty acid before the incorporation; GLA(18:3) and SDA(18:4) were unfavorable for the CL incorporation.
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Affiliation(s)
- Hsiu-Chi Ting
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China
| | - Li-Tzu Chen
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China
| | - Jo-Yu Chen
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China
| | - Yi-Li Huang
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China
| | - Rui-Cheng Xin
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China
| | - Jui-Fen Chan
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China
| | - Yuan-Hao Howard Hsu
- Department of Chemistry, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China. .,Life Science Research Center, Tunghai University, No.1727, Sec4, Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan, Republic of China.
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Nyamugenda E, Trentzsch M, Russell S, Miles T, Boysen G, Phelan KD, Baldini G. Injury to hypothalamic Sim1 neurons is a common feature of obesity by exposure to high-fat diet in male and female mice. J Neurochem 2019; 149:73-97. [PMID: 30615192 DOI: 10.1111/jnc.14662] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 10/16/2018] [Accepted: 01/04/2019] [Indexed: 12/13/2022]
Abstract
The hypothalamus is essential for regulation of energy homeostasis and metabolism. Feeding hypercaloric, high-fat (HF) diet induces hypothalamic arcuate nucleus injury and alters metabolism more severely in male than in female mice. The site(s) and extent of hypothalamic injury in male and female mice are not completely understood. In the paraventricular nucleus (PVN) of the hypothalamus, single-minded family basic helix-loop helix transcription factor 1 (Sim1) neurons are essential to control energy homeostasis. We tested the hypothesis that exposure to HF diet induces injury to Sim1 neurons in the PVN of male and female mice. Mice expressing membrane-bound enhanced green fluorescent protein (mEGFP) in Sim1 neurons (Sim1-Cre:Rosa-mEGFP mice) were generated to visualize the effects of exposure to HF diet on these neurons. Male and female Sim1-Cre:Rosa-mEGFP mice exposed to HF diet had increased weight, hyperleptinemia, and developed hepatosteatosis. In male and female mice exposed to HF diet, expression of mEGFP was reduced by > 40% in Sim1 neurons of the PVN, an effect paralleled by cell apoptosis and neuronal loss, but not by microgliosis. In the arcuate nucleus of the Sim1-Cre:Rosa-mEGFP male mice, there was decreased alpha-melanocyte-stimulating hormone in proopiomelanocortin neurons projecting to the PVN, with increased cell apoptosis, neuronal loss, and microgliosis. These defects were undetectable in the arcuate nucleus of female mice exposed to the HF diet. Thus, injury to Sim1 neurons of the PVN is a shared feature of exposure to HF diet in mice of both sexes, while injury to proopiomelanocortin neurons in arcuate nucleus is specific to male mice. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Eugene Nyamugenda
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Marcus Trentzsch
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Susan Russell
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Tiffany Miles
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Gunnar Boysen
- Department of Environmental and Occupational Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.,The Winthrop P Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Kevin D Phelan
- Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Giulia Baldini
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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12
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Brain docosahexaenoic acid uptake and metabolism. Mol Aspects Med 2018; 64:109-134. [PMID: 29305120 DOI: 10.1016/j.mam.2017.12.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 12/21/2017] [Accepted: 12/28/2017] [Indexed: 12/22/2022]
Abstract
Docosahexaenoic acid (DHA) is the most abundant n-3 polyunsaturated fatty acid in the brain where it serves to regulate several important processes and, in addition, serves as a precursor to bioactive mediators. Given that the capacity of the brain to synthesize DHA locally is appreciably low, the uptake of DHA from circulating lipid pools is essential to maintaining homeostatic levels. Although, several plasma pools have been proposed to supply the brain with DHA, recent evidence suggests non-esterified-DHA and lysophosphatidylcholine-DHA are the primary sources. The uptake of DHA into the brain appears to be regulated by a number of complementary pathways associated with the activation and metabolism of DHA, and may provide mechanisms for enrichment of DHA within the brain. Following entry into the brain, DHA is esterified into and recycled amongst membrane phospholipids contributing the distribution of DHA in brain phospholipids. During neurotransmission and following brain injury, DHA is released from membrane phospholipids and converted to bioactive mediators which regulate signaling pathways important to synaptogenesis, cell survival, and neuroinflammation, and may be relevant to treating neurological diseases. In the present review, we provide a comprehensive overview of brain DHA metabolism, encompassing many of the pathways and key enzymatic regulators governing brain DHA uptake and metabolism. In addition, we focus on the release of non-esterified DHA and subsequent production of bioactive mediators and the evidence of their proposed activity within the brain. We also provide a brief review of the evidence from post-mortem brain analyses investigating DHA levels in the context of neurological disease and mood disorder, highlighting the current disparities within the field.
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13
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Zanderigo F, Kang Y, Kumar D, Nikolopoulou A, Mozley PD, Kothari PJ, He B, Schlyer D, Rapoport SI, Oquendo MA, Vallabhajosula S, Mann JJ, Sublette ME. [ 11 C]arachidonic acid incorporation measurement in human brain: Optimization for clinical use. Synapse 2017; 72. [PMID: 29144569 DOI: 10.1002/syn.22018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 11/10/2017] [Accepted: 11/12/2017] [Indexed: 01/06/2023]
Abstract
Arachidonic acid (AA) is involved in signal transduction, neuroinflammation, and production of eicosanoid metabolites. The AA brain incorporation coefficient (K*) is quantifiable in vivo using [11 C]AA positron emission tomography, although repeatability remains undetermined. We evaluated K* estimates obtained with population-based metabolite correction (PBMC) and image-derived input function (IDIF) in comparison to arterial blood-based estimates, and compared repeatability. Eleven healthy volunteers underwent a [11 C]AA scan; five repeated the scan 6 weeks later, simulating a pre- and post-treatment study design. For all scans, arterial blood was sampled to measure [11 C]AA plasma radioactivity. Plasma [11 C]AA parent fraction was measured in 5 scans. K* was quantified using both blood data and IDIF, corrected for [11 C]AA parent fraction using both PBMC (from published values) and individually measured values (when available). K* repeatability was calculated in the test-retest subset. K* estimates based on blood and individual metabolites were highly correlated with estimates using PBMC with arterial input function (r = 0.943) or IDIF (r = 0.918) in the subset with measured metabolites. In the total dataset, using PBMC, IDIF-based estimates were moderately correlated with arterial input function-based estimates (r = 0.712). PBMC and IDIF-based K* estimates were ∼6.4% to ∼11.9% higher, on average, than blood-based estimates. Average K* test-retest absolute percent difference values obtained using blood data or IDIF, assuming PBMC for both, were between 6.7% and 13.9%, comparable to other radiotracers. Our results support the possibility of simplified [11 C]AA data acquisition through eliminating arterial blood sampling and metabolite analysis, while retaining comparable repeatability and validity.
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Affiliation(s)
- Francesca Zanderigo
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, New York.,Department of Psychiatry, Columbia University, New York, New York
| | - Yeona Kang
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | - Dileep Kumar
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, New York
| | | | - P David Mozley
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | - Paresh J Kothari
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | - Bin He
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | - David Schlyer
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | | | - Maria A Oquendo
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, New York.,Department of Psychiatry, Columbia University, New York, New York
| | | | - J John Mann
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, New York.,Department of Psychiatry, Columbia University, New York, New York.,Department of Radiology, Columbia University, New York, New York
| | - M Elizabeth Sublette
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, New York.,Department of Psychiatry, Columbia University, New York, New York
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14
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Neth BJ, Craft S. Insulin Resistance and Alzheimer's Disease: Bioenergetic Linkages. Front Aging Neurosci 2017; 9:345. [PMID: 29163128 PMCID: PMC5671587 DOI: 10.3389/fnagi.2017.00345] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/13/2017] [Indexed: 12/14/2022] Open
Abstract
Metabolic dysfunction is a well-established feature of Alzheimer's disease (AD), evidenced by brain glucose hypometabolism that can be observed potentially decades prior to the development of AD symptoms. Furthermore, there is mounting support for an association between metabolic disease and the development of AD and related dementias. Individuals with insulin resistance, type 2 diabetes mellitus (T2D), hyperlipidemia, obesity, or other metabolic disease may have increased risk for the development of AD and similar conditions, such as vascular dementia. This association may in part be due to the systemic mitochondrial dysfunction that is common to these pathologies. Accumulating evidence suggests that mitochondrial dysfunction is a significant feature of AD and may play a fundamental role in its pathogenesis. In fact, aging itself presents a unique challenge due to inherent mitochondrial dysfunction and prevalence of chronic metabolic disease. Despite the progress made in understanding the pathogenesis of AD and in the development of potential therapies, at present we remain without a disease-modifying treatment. In this review, we will discuss insulin resistance as a contributing factor to the pathogenesis of AD, as well as the metabolic and bioenergetic disruptions linking insulin resistance and AD. We will also focus on potential neuroimaging tools for the study of the metabolic dysfunction commonly seen in AD with hopes of developing therapeutic and preventative targets.
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Affiliation(s)
- Bryan J Neth
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Suzanne Craft
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
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15
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Chouinard-Watkins R, Chen CT, Metherel AH, Lacombe RS, Thies F, Masoodi M, Bazinet RP. Phospholipid class-specific brain enrichment in response to lysophosphatidylcholine docosahexaenoic acid infusion. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:1092-1098. [DOI: 10.1016/j.bbalip.2017.07.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 07/04/2017] [Accepted: 07/26/2017] [Indexed: 12/15/2022]
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16
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Metherel AH, Kitson AP, Domenichiello AF, Lacombe RJS, Hopperton KE, Trépanier MO, Alashmali SM, Lin L, Bazinet RP. Docosahexaenoic acid (DHA) accretion in the placenta but not the fetus is matched by plasma unesterified DHA uptake rates in pregnant Long Evans rats. Placenta 2017; 58:90-97. [PMID: 28962703 DOI: 10.1016/j.placenta.2017.08.072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/31/2017] [Accepted: 08/29/2017] [Indexed: 12/12/2022]
Abstract
Maternal delivery of docosahexaenoic acid (DHA, 22:6n-3) to the developing fetus via the placenta is required for fetal neurodevelopment, and is the only mechanism by which DHA can be accreted in the fetus. The aim of the current study was to utilize a balance model of DHA accretion combined with kinetic measures of serum unesterified DHA uptake to better understand the mechanism by which maternal DHA is delivered to the fetus via the placenta. Female rats maintained on a 2% α-linolenic acid diet free of DHA for 56 days were mated, and for balance analysis, sacrificed at 18 days of pregnancy, and fetus, placenta and maternal carcass fatty acid concentration were determined. For tissue DHA uptake, pregnant dams (14-18 days) were infused for 5 min with radiolabeled 14C-DHA and kinetic modeling was used to determine fetal and placental serum unesterified DHA uptake rates. DHA accretion rates in the fetus were determined to be 38 ± 2 nmol/d/g, 859 ± 100 nmol/d/litter and 74 ± 3 nmol/d/pup, which are all higher (P < 0.05) than the fetal serum unesterified DHA uptake rates of 16 ± 6 nmol/d/g, 239 ± 145 nmol/d/litter and 14 ± 8 nmol/d/pup. No differences (p > 0.05) in placental DHA accretion rates versus serum unesterified DHA uptake rates were observed as values varied only 6-35% between studies. No differences in placental accretion and uptake rates suggests that serum unesterified DHA is a significant pool for the maternal-placental transfer of DHA, and lower fetal DHA uptake compared to accretion supports remodeling of placental DHA for delivery to the fetus.
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Affiliation(s)
- Adam H Metherel
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada.
| | - Alex P Kitson
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - Anthony F Domenichiello
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - R J Scott Lacombe
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - Kathryn E Hopperton
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - Marc-Olivier Trépanier
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - Shoug M Alashmali
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - Lin Lin
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario M5S 3E2, Canada
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17
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Valnoctamide, which reduces rat brain arachidonic acid turnover, is a potential non-teratogenic valproate substitute to treat bipolar disorder. Psychiatry Res 2017; 254:279-283. [PMID: 28500975 PMCID: PMC5524208 DOI: 10.1016/j.psychres.2017.04.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 04/11/2017] [Accepted: 04/22/2017] [Indexed: 02/06/2023]
Abstract
BACKGROUND Valproic acid (VPA), used for treating bipolar disorder (BD), is teratogenic by inhibiting histone deacetylase. In unanaesthetized rats, chronic VPA, like other mood stabilizers, reduces arachidonic acid (AA) turnover in brain phospholipids, and inhibits AA activation to AA-CoA by recombinant acyl-CoA synthetase-4 (Acsl-4) in vitro. Valnoctamide (VCD), a non-teratogenic constitutional isomer of VPA amide, reported effective in BD, also inhibits recombinant Acsl-4 in vitro. HYPOTHESIS VCD like VPA will reduce brain AA turnover in unanaesthetized rats. METHODS A therapeutically relevant (50mg/kg i.p.) dose of VCD or vehicle was administered daily for 30 days to male rats. AA turnover and related parameters were determined using our kinetic model, following intravenous [1-14C]AA in unanaesthetized rats for 10min, and measuring labeled and unlabeled lipids in plasma and high-energy microwaved brain. RESULTS VCD, compared with vehicle, increased λ, the ratio of brain AA-CoA to unesterified plasma AA specific activities; and decreased turnover of AA in individual and total brain phospholipids. CONCLUSIONS VCD's ability like VPA to reduce rat brain AA turnover and inhibit recombinant Acsl-4, and its efficacy in BD, suggest that VCD be further considered as a non-teratogenic VPA substitute for treating BD.
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18
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Lacombe RJS, Giuliano V, Colombo SM, Arts MT, Bazinet RP. Compound-specific isotope analysis resolves the dietary origin of docosahexaenoic acid in the mouse brain. J Lipid Res 2017; 58:2071-2081. [PMID: 28694298 DOI: 10.1194/jlr.d077990] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/05/2017] [Indexed: 12/23/2022] Open
Abstract
DHA (22:6n-3) may be derived from two dietary sources, preformed dietary DHA or through synthesis from α-linolenic acid (ALA; 18:3n-3). However, conventional methods cannot distinguish between DHA derived from either source without the use of costly labeled tracers. In the present study, we demonstrate the proof-of-concept that compound-specific isotope analysis (CSIA) by GC-isotope ratio mass spectrometry (IRMS) can differentiate between sources of brain DHA based on differences in natural 13C enrichment. Mice were fed diets containing either purified ALA or DHA as the sole n-3 PUFA. Extracted lipids were analyzed by CSIA for natural abundance 13C enrichment. Brain DHA from DHA-fed mice was significantly more enriched (-23.32‰ to -21.92‰) compared with mice on the ALA diet (-28.25‰ to -27.49‰). The measured 13C enrichment of brain DHA closely resembled the dietary n-3 PUFA source, -21.86‰ and -28.22‰ for DHA and ALA, respectively. The dietary effect on DHA 13C enrichment was similar in liver and blood fractions. Our results demonstrate the effectiveness of CSIA, at natural 13C enrichment, to differentiate between the incorporation of preformed or synthesized DHA into the brain and other tissues without the need for tracers.
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Affiliation(s)
- R J Scott Lacombe
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Vanessa Giuliano
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Stefanie M Colombo
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
| | - Michael T Arts
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
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19
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Metherel AH, Kitson AP, Domenichiello AF, Lacombe RJS, Hopperton KE, Trépanier MO, Alashmali SM, Lin L, Bazinet RP. Maternal liver docosahexaenoic acid (DHA) stores are increased via higher serum unesterified DHA uptake in pregnant long Evans rats. J Nutr Biochem 2017. [PMID: 28628798 DOI: 10.1016/j.jnutbio.2017.05.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Maternal docosahexaenoic acid (DHA, 22:6n-3) supplies the developing fetus during pregnancy; however, the mechanisms are unclear. We utilized pregnant rats to determine rates of DHA accretion, tissue unesterified DHA uptake and whole-body DHA synthesis-secretion. Female rats maintained on a DHA-free, 2% α-linolenic acid diet were either:1) sacrificed at 56 days for baseline measures, 2) mated and sacrificed at 14-18 days of pregnancy or 3) or sacrificed at 14-18 days as age-matched virgin controls. Maternal brain, adipose, liver and whole body fatty acid concentrations was determined for balance analysis, and kinetic modeling was used to determine brain and liver plasma unesterified DHA uptake and whole-body DHA synthesis-secretion rates. Total liver DHA was significantly higher in pregnant (95±5 μmol) versus non-pregnant (49±5) rats with no differences in whole-body DHA synthesis-secretion rates. However, liver uptake of plasma unesterified DHA was 3.8-fold higher in pregnant animals compared to non-pregnant controls, and periuterine adipose DHA was lower in pregnant (0.89±0.09 μmol/g) versus non-pregnant (1.26±0.06) rats. In conclusion, higher liver DHA accretion during pregnancy appears to be driven by higher unesterified DHA uptake, potentially via DHA mobilization from periuterine adipose for delivery to the fetus during the brain growth spurt.
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Affiliation(s)
- Adam H Metherel
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2.
| | - Alex P Kitson
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - Anthony F Domenichiello
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - R J Scott Lacombe
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - Kathryn E Hopperton
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - Marc-Olivier Trépanier
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - Shoug M Alashmali
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - Lin Lin
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 150 College St., Toronto, Ontario, Canada, M5S 3E2
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20
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Yassine HN, Croteau E, Rawat V, Hibbeln JR, Rapoport SI, Cunnane SC, Umhau JC. DHA brain uptake and APOE4 status: a PET study with [1- 11C]-DHA. ALZHEIMERS RESEARCH & THERAPY 2017; 9:23. [PMID: 28335828 PMCID: PMC5364667 DOI: 10.1186/s13195-017-0250-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 02/28/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND The apolipoprotein E ɛ4 (APOE4) allele is the strongest genetic risk factor identified for developing Alzheimer's disease (AD). Among brain lipids, alteration in the ω-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) homeostasis is implicated in AD pathogenesis. APOE4 may influence both brain DHA metabolism and cognitive outcomes. METHODS Using positron emission tomography, regional incorporation coefficients (k*), rates of DHA incorporation from plasma into the brain using [1-11C]-DHA (J in), and regional cerebral blood flow using [15O]-water were measured in 22 middle-aged healthy adults (mean age 35 years, range 19-65 years). Data were partially volume error-corrected for brain atrophy. APOE4 phenotype was determined by protein expression, and unesterified DHA concentrations were quantified in plasma. An exploratory post hoc analysis of the effect of APOE4 on DHA brain kinetics was performed. RESULTS The mean global gray matter DHA incorporation coefficient, k*, was significantly higher (16%) among APOE4 carriers (n = 9) than among noncarriers (n = 13, p = 0.046). Higher DHA incorporation coefficients were observed in several brain regions, particularly in the entorhinal subregion, an area affected early in AD pathogenesis. Cerebral blood flow, unesterified plasma DHA, and whole brain DHA incorporation rate (J in) did not differ significantly between the APOE groups. CONCLUSIONS Our findings suggest an increase in the DHA incorporation coefficient in several brain regions in APOE4 carriers. These findings may contribute to understanding how APOE4 genotypes affect AD risk.
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Affiliation(s)
- Hussein N Yassine
- Department of Medicine, University of Southern California, 2250 Alcazar Street, Room 210, Los Angeles, CA, 90033, USA.
| | - Etienne Croteau
- Research Center on Aging, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Varun Rawat
- Department of Medicine, University of Southern California, 2250 Alcazar Street, Room 210, Los Angeles, CA, 90033, USA
| | - Joseph R Hibbeln
- Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD, USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Stephen C Cunnane
- Research Center on Aging, University of Sherbrooke, Sherbrooke, QC, Canada
| | - John C Umhau
- Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD, USA.,Division of Psychiatry Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, College Park, MD, USA
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21
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Brain uptake and metabolism of the endocannabinoid anandamide labeled in either the arachidonoyl or ethanolamine moiety. Nucl Med Biol 2017; 45:43-50. [DOI: 10.1016/j.nucmedbio.2016.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/27/2016] [Accepted: 11/01/2016] [Indexed: 12/20/2022]
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22
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Dietary Linoleic Acid Lowering Reduces Lipopolysaccharide-Induced Increase in Brain Arachidonic Acid Metabolism. Mol Neurobiol 2016; 54:4303-4315. [PMID: 27339880 DOI: 10.1007/s12035-016-9968-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 06/08/2016] [Indexed: 12/29/2022]
Abstract
Linoleic acid (LA, 18:2n-6) is a precursor to arachidonic acid (AA, 20:4n-6), which can be converted by brain lipoxygenase and cyclooxygenase (COX) enzymes into various lipid mediators involved in the regulation of brain immunity. Brain AA metabolism is activated in rodents by the bacterial endotoxin, lipopolysaccharide (LPS). This study tested the hypothesis that dietary LA lowering, which limits plasma supply of AA to the brain, reduces LPS-induced upregulation in brain AA metabolism. Male Fischer CDF344 rats fed an adequate LA (5.2 % energy (en)) or low LA (0.4 % en) diet for 15 weeks were infused with LPS (250 ng/h) or vehicle into the fourth ventricle for 2 days using a mini-osmotic pump. The incorporation rate of intravenously infused unesterified 14C-AA into brain lipids, eicosanoids, and activities of phospholipase A2 and COX-1 and 2 enzymes were measured. Dietary LA lowering reduced the LPS-induced increase in prostaglandin E2 concentration and COX-2 activity (P < 0.05 by two-way ANOVA) without altering phospholipase activity. The 14C-AA incorporation rate into brain lipids was decreased by dietary LA lowering (P < 0.05 by two-way ANOVA). The present findings suggest that dietary LA lowering reduced LPS-induced increase in brain markers of AA metabolism. The clinical utility of LA lowering in brain disorders should be explored in future studies.
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23
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Cansev M. Synaptogenesis: Modulation by Availability of Membrane Phospholipid Precursors. Neuromolecular Med 2016; 18:426-40. [DOI: 10.1007/s12017-016-8414-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 05/24/2016] [Indexed: 10/21/2022]
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24
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Kitson AP, Metherel AH, Chen CT, Domenichiello AF, Trépanier MO, Berger A, Bazinet RP. Effect of dietary docosahexaenoic acid (DHA) in phospholipids or triglycerides on brain DHA uptake and accretion. J Nutr Biochem 2016; 33:91-102. [PMID: 27135386 DOI: 10.1016/j.jnutbio.2016.02.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 01/27/2016] [Accepted: 02/11/2016] [Indexed: 11/28/2022]
Abstract
Tracer studies suggest that phospholipid DHA (PL-DHA) more effectively targets the brain than triglyceride DHA (TAG-DHA), although the mechanism and whether this translates into higher brain DHA concentrations are not clear. Rats were gavaged with [U-(3)H]PL-DHA and [U-(3)H]TAG-DHA and blood sampled over 6h prior to collection of brain regions and other tissues. In another experiment, rats were supplemented for 4weeks with TAG-DHA (fish oil), PL-DHA (roe PL) or a mixture of both for comparison to a low-omega-3 diet. Brain regions and other tissues were collected, and blood was sampled weekly. DHA accretion rates were estimated using the balance method. [U-(3)H]PL-DHA rats had higher radioactivity in cerebellum, hippocampus and remainder of brain, with no differences in other tissues despite higher serum lipid radioactivity in [U-(3)H]TAG-DHA rats. TAG-DHA, PL-DHA or a mixture were equally effective at increasing brain DHA. There were no differences between DHA-supplemented groups in brain region, whole-body, or tissue DHA accretion rates except heart and serum TAG where the PL-DHA/TAG-DHA blend was higher than TAG-DHA. Apparent DHA β-oxidation was not different between DHA-supplemented groups. This indicates that more labeled DHA enters the brain when consumed as PL; however, this may not translate into higher brain DHA concentrations.
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Affiliation(s)
- Alex P Kitson
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, M5S3E2, Canada
| | - Adam H Metherel
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, M5S3E2, Canada
| | - Chuck T Chen
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, M5S3E2, Canada
| | | | - Marc-Olivier Trépanier
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, M5S3E2, Canada
| | - Alvin Berger
- Arctic Nutrition AS, NO-6155, Ørsta, Norway; Department of Food Science & Nutrition, University of Minnesota, St. Paul, MN, 55108-1038, USA
| | - Richard P Bazinet
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, M5S3E2, Canada.
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25
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Mouse Strain Impacts Fatty Acid Uptake and Trafficking in Liver, Heart, and Brain: A Comparison of C57BL/6 and Swiss Webster Mice. Lipids 2016; 51:549-60. [PMID: 26797754 DOI: 10.1007/s11745-015-4117-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 12/10/2015] [Indexed: 01/21/2023]
Abstract
C57BL/6 and Swiss Webster mice are used to study lipid metabolism, although differences in fatty acid uptake between these strains have not been reported. Using a steady state kinetic model, [1-(14)C]16:0, [1-(14)C]20:4n-6, or [1-(14)C]22:6n-3 was infused into awake, adult male mice and uptake into liver, heart, and brain determined. The integrated area of [1-(14)C]20:4n-6 in plasma was significantly increased in C57BL/6 mice, but [1-(14)C]16:0 and [1-(14)C]22:6n-3 were not different between groups. In heart, uptake of [1-(14)C]20:4n-6 was increased 1.7-fold in C57BL/6 mice. However, trafficking of [1-(14)C]22:6n-3 into the organic fraction of heart was significantly decreased 33 % in C57BL/6 mice. Although there were limited differences in fatty acid tracer trafficking in liver or brain, [1-(14)C]16:0 incorporation into liver neutral lipids was decreased 18 % in C57BL/6 mice. In heart, the amount of [1-(14)C]16:0 and [1-(14)C]22:6n-3 incorporated into total phospholipids were decreased 45 and 49 %, respectively, in C57BL/6 mice. This was accounted for by a 53 and 37 % decrease in [1-(14)C]16:0 and 44 and 52 % decrease in [1-(14)C]22:6n-3 entering ethanolamine glycerophospholipids and choline glycerophospholipids, respectively. In contrast, there was a significant increase in [1-(14)C]20:4n-6 esterification into all heart phospholipids of C57BL/6 mice. Although changes in uptake were limited to heart, several significant differences were found in fatty acid trafficking into heart, liver, and brain phospholipids. In summary, our data demonstrates differences in tissue fatty acid uptake and trafficking between mouse strains is an important consideration when carrying out fatty acid metabolic studies.
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Saunders EFH, Reider A, Singh G, Gelenberg AJ, Rapoport SI. Low unesterified:esterified eicosapentaenoic acid (EPA) plasma concentration ratio is associated with bipolar disorder episodes, and omega-3 plasma concentrations are altered by treatment. Bipolar Disord 2015; 17:729-42. [PMID: 26424416 PMCID: PMC4623957 DOI: 10.1111/bdi.12337] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 08/01/2015] [Indexed: 01/09/2023]
Abstract
OBJECTIVES Omega (n)-3 and n-6 polyunsaturated fatty acids (PUFAs) are molecular modulators of neurotransmission and inflammation. We hypothesized that plasma concentrations of n-3 PUFAs would be lower and those of n-6 PUFAs higher in subjects with bipolar disorder (BD) compared to healthy controls (HCs), and would correlate with symptom severity in subjects with BD, and that effective treatment would correlate with increased n-3 but lower n-6 PUFA levels. Additionally, we explored clinical correlations and group differences in plasma levels of saturated and monounsaturated fatty acids. METHODS This observational, parallel group study compared biomarkers between HCs (n = 31) and symptomatic subjects with BD (n = 27) when ill and after symptomatic recovery (follow-up). Plasma concentrations of five PUFAs [linoleic acid (LA), arachidonic acid (AA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA)], two saturated fatty acids (palmitic acid and stearic acid) and two monounsaturated fatty acids (palmitoleic acid and oleic acid) were measured in esterified (E) and unesterified (UE) forms. Calculated ratios included UE:E for the five PUFAs, ratios of n-3 PUFAs (DHA:ALA, EPA:ALA and EPA:DHA), and the ratio of n-6:n-3 AA:EPA. Comparisons of plasma fatty acid levels and ratios between BD and HC groups were made with Student t-tests, and between the BD group at baseline and follow-up using paired t-tests. Comparison of categorical variables was performed using chi-square tests. Pearson's r was used for bivariate correlations with clinical variables, including depressive and manic symptoms, current panic attacks, and psychosis. RESULTS UE EPA was lower in subjects with BD than in HCs, with a large effect size (Cohen's d = 0.86, p < 0.002); however, it was not statistically significant after correction for multiple comparisons. No statistically significant difference was seen in any plasma PUFA concentration between the BD and HC groups after Bonferroni correction for 40 comparisons, at p < 0.001. Neither depressive severity nor mania severity was correlated significantly with any PUFA concentration. Exploratory comparison showed lower UE:E EPA in the BD than the HC group (p < 0.0001). At follow-up in the BD group, UE, E DHA:ALA, and UE EPA:ALA were decreased (p < 0.002). Exploratory correlations of clinical variables revealed that mania severity and suicidality were positively correlated with UE:E EPA ratio, and that several plasma levels and ratios correlated with panic disorder and psychosis. Depressive severity was not correlated with any ratio. No plasma fatty acid level or ratio correlated with self-reported n-3 PUFA intake or use of medication by class. CONCLUSIONS A large effect size of reduced UE EPA, and a lower plasma UE:E concentration ratio of EPA in the symptomatic BD state may be important factors in vulnerability to a mood state. Altered n-3 PUFA ratios could indicate changes in PUFA metabolism concurrent with symptom improvement. Our findings are consistent with preclinical and postmortem data and suggest testing interventions that increase n-3 and decrease n-6 dietary PUFA intake.
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Affiliation(s)
- Erika FH Saunders
- Department of Psychiatry, Penn State College of Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA,University of Michigan Department of Psychiatry, Ann Arbor, MI,University of Michigan Depression Center, Ann Arbor, MI
| | - Aubrey Reider
- Department of Psychiatry, Penn State College of Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA
| | - Gagan Singh
- Department of Psychiatry, Penn State College of Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA
| | - Alan J Gelenberg
- Department of Psychiatry, Penn State College of Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
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Plasma non-esterified docosahexaenoic acid is the major pool supplying the brain. Sci Rep 2015; 5:15791. [PMID: 26511533 PMCID: PMC4625162 DOI: 10.1038/srep15791] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 10/05/2015] [Indexed: 12/27/2022] Open
Abstract
Despite being critical for normal brain function, the pools that supply docosahexaenoic acid (DHA) to the brain are not agreed upon. Using multiple kinetic models in free-living adult rats, we first demonstrate that DHA uptake from the plasma non-esterified fatty acid (NEFA) pool predicts brain uptake of DHA upon oral administration, which enters the plasma NEFA pool as well as multiple plasma esterified pools. The rate of DHA loss by the brain is similar to the uptake from the plasma NEFA pool. Furthermore, upon acute iv administration, although more radiolabeled lysophosphatidylcholine (LPC)-DHA enters the brain than NEFA-DHA, this is due to the longer plasma half-life and exposure to the brain. Direct comparison of the uptake rate of LPC-DHA and NEFA-DHA demonstrates that uptake of NEFA-DHA into the brain is 10-fold greater than LPC-DHA. In conclusion, plasma NEFA-DHA is the major plasma pool supplying the brain.
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Blanchard H, Chang L, Rezvani AH, Rapoport SI, Taha AY. Brain Arachidonic Acid Incorporation and Turnover are not Altered in the Flinders Sensitive Line Rat Model of Human Depression. Neurochem Res 2015; 40:2293-303. [PMID: 26404538 DOI: 10.1007/s11064-015-1719-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 09/05/2015] [Accepted: 09/08/2015] [Indexed: 11/25/2022]
Abstract
Brain serotonergic signaling is coupled to arachidonic acid (AA)-releasing calcium-dependent phospholipase A2. Increased brain serotonin concentrations and disturbed serotonergic neurotransmission have been reported in the Flinders Sensitive Line (FSL) rat model of depression, suggesting that brain AA metabolism may be elevated. To test this hypothesis, (14)C-AA was intravenously infused to steady-state levels into control and FSL rats derived from the same Sprague-Dawley background strain, and labeled and unlabeled brain phospholipid and plasma fatty acid concentrations were measured to determine the rate of brain AA incorporation and turnover. Brain AA incorporation and turnover did not differ significantly between controls and FSL rats. Compared to controls, plasma unesterified docosahexaenoic acid was increased, and brain phosphatidylinositol AA and total lipid linoleic acid and n-3 and n-6 docosapentaenoic acid were significantly decreased in FSL rats. Several plasma esterified fatty acids differed significantly from controls. In summary, brain AA metabolism did not change in FSL rats despite reported increased levels of serotonin concentrations, suggesting possible post-synaptic dampening of serotonergic neurotransmission involving AA.
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Affiliation(s)
- Helene Blanchard
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Lisa Chang
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Amir H Rezvani
- Department of Psychiatric and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Ameer Y Taha
- Department of Food Science and Technology, College of Agriculture and Environmental Sciences, University of California, RMI North, Room 3162, Davis, CA, USA.
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Trépanier MO, Kwong KM, Domenichiello AF, Chen CT, Bazinet RP, Burnham WM. Intravenous infusion of docosahexaenoic acid increases serum concentrations in a dose-dependent manner and increases seizure latency in the maximal PTZ model. Epilepsy Behav 2015; 50:71-6. [PMID: 26141815 DOI: 10.1016/j.yebeh.2015.05.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 05/20/2015] [Accepted: 05/22/2015] [Indexed: 12/18/2022]
Abstract
Docosahexaenoic acid (DHA) is an omega-3 polyunsaturated fatty acid (n-3 PUFA) that has been shown to raise seizure thresholds in the maximal pentylenetetrazole model following acute subcutaneous (s.c.) administration in rats. Following s.c. administration, however, the dose-response relationship for DHA has shown an inverted U-pattern. The purposes of the present experiment were as follows: (1) to determine the pattern of serum unesterified concentrations resulting from the intravenous (i.v.) infusions of various doses of DHA, (2) to determine the time course of these concentrations following the discontinuation of the infusions, and (3) to determine whether seizure protection in the maximal PTZ model would correlate with serum unesterified DHA levels. Animals received 5-minute i.v. infusions of saline or 25, 50, 100, or 200mg/kg of DHA via a cannula inserted into one of the tail veins. Blood was collected during and after the infusions by means of a second cannula inserted into the other tail vein (Experiment 1). A separate group of animals received saline or 12.5-, 25-, 50-, 100-, or 200 mg/kg DHA i.v. via a cannula inserted into one of the tail veins and were then seizure-tested in the maximal PTZ model either during infusion or after the discontinuation of the infusions. Slow infusions of DHA increased serum unesterified DHA concentrations in a dose-dependent manner, with the 200-mg/kg dose increasing the concentration approximately 260-fold compared with saline-infused animals. Following discontinuation of the infusions, serum concentrations rapidly dropped toward baseline, with half-lives of approximately 40 and 11s for the 25-mg/kg dose and 100-mg/kg dose, respectively. In the seizure-tested animals, DHA significantly increased latency to seizure onset in a dose-dependent manner. Following the discontinuation of infusion, seizure latency rapidly decreased toward baseline. Overall, our study suggests that i.v. infusion of unesterified DHA results in transient anticonvulsant effects which parallel unesterified DHA serum concentrations.
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Affiliation(s)
- Marc-Olivier Trépanier
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; University of Toronto Epilepsy Research Program, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Kei-Man Kwong
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5S 1A8, Canada; University of Toronto Epilepsy Research Program, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Anthony F Domenichiello
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Chuck T Chen
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; University of Toronto Epilepsy Research Program, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - W M Burnham
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5S 1A8, Canada; University of Toronto Epilepsy Research Program, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada.
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Domenichiello AF, Kitson AP, Bazinet RP. Is docosahexaenoic acid synthesis from α-linolenic acid sufficient to supply the adult brain? Prog Lipid Res 2015; 59:54-66. [DOI: 10.1016/j.plipres.2015.04.002] [Citation(s) in RCA: 142] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 04/09/2015] [Indexed: 12/13/2022]
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Liu JJ, Green P, John Mann J, Rapoport SI, Sublette ME. Pathways of polyunsaturated fatty acid utilization: implications for brain function in neuropsychiatric health and disease. Brain Res 2015; 1597:220-46. [PMID: 25498862 PMCID: PMC4339314 DOI: 10.1016/j.brainres.2014.11.059] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 11/11/2014] [Accepted: 11/27/2014] [Indexed: 12/28/2022]
Abstract
Essential polyunsaturated fatty acids (PUFAs) have profound effects on brain development and function. Abnormalities of PUFA status have been implicated in neuropsychiatric diseases such as major depression, bipolar disorder, schizophrenia, Alzheimer's disease, and attention deficit hyperactivity disorder. Pathophysiologic mechanisms could involve not only suboptimal PUFA intake, but also metabolic and genetic abnormalities, defective hepatic metabolism, and problems with diffusion and transport. This article provides an overview of physiologic factors regulating PUFA utilization, highlighting their relevance to neuropsychiatric disease.
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Affiliation(s)
- Joanne J Liu
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA; New York Medical College, Valhalla, NY, USA
| | - Pnina Green
- Laboratory of Metabolic Research, Felsenstein Medical Research Center, Tel Aviv University, Petach Tikva, Israel
| | - J John Mann
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University, New York, NY, USA; Department of Radiology, Columbia University, New York, NY, USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - M Elizabeth Sublette
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University, New York, NY, USA.
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Chen CT, Bazinet RP. β-oxidation and rapid metabolism, but not uptake regulate brain eicosapentaenoic acid levels. Prostaglandins Leukot Essent Fatty Acids 2015; 92:33-40. [PMID: 24986271 DOI: 10.1016/j.plefa.2014.05.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The brain has a unique polyunsaturated fatty acid composition, with high levels of arachidonic and docosahexaenoic acids (DHA) while levels of eicosapentaenoic acid (EPA) are several orders of magnitude lower. As evidence accumulated that fatty acid entry into the brain was not selective and, in fact, that DHA and EPA enter the brain at similar rates, new mechanisms were required to explain their large concentration differences in the brain. Here we summarize recent research demonstrating that EPA is rapidly and extensively β-oxidized upon entry into the brain. Although the ATP generated from the β-oxidation of EPA is low compared to the use of glucose, fatty acid β-oxidation may serve to regulate brain fatty acid levels in the absence of selective transportation. Furthermore, when β-oxidation of EPA is blocked, desaturation of EPA increases and Land׳s recycling decreases to maintain low EPA levels.
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Affiliation(s)
- Chuck T Chen
- Department of Nutritional Sciences, University of Toronto, Fitzgerald Building, 150 College St. Room 306, Ontario, Toronto, M5S 3E2 Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, University of Toronto, Fitzgerald Building, 150 College St. Room 306, Ontario, Toronto, M5S 3E2 Canada.
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Lin LE, Chen CT, Hildebrand KD, Liu Z, Hopperton KE, Bazinet RP. Chronic dietary n-6 PUFA deprivation leads to conservation of arachidonic acid and more rapid loss of DHA in rat brain phospholipids. J Lipid Res 2014; 56:390-402. [PMID: 25477531 DOI: 10.1194/jlr.m055590] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
To determine how the level of dietary n-6 PUFA affects the rate of loss of arachidonic acid (ARA) and DHA in brain phospholipids, male rats were fed either a deprived or adequate n-6 PUFA diet for 15 weeks postweaning, and then subjected to an intracerebroventricular infusion of (3)H-ARA or (3)H-DHA. Brains were collected at fixed times over 128 days to determine half-lives and the rates of loss from brain phospholipids (J out). Compared with the adequate n-6 PUFA rats, the deprived n-6-PUFA rats had a 15% lower concentration of ARA and an 18% higher concentration of DHA in their brain total phospholipids. Loss half-lives of ARA in brain total phospholipids and fractions (except phosphatidylserine) were longer in the deprived n-6 PUFA rats, whereas the J out was decreased. In the deprived versus adequate n-6 PUFA rats, the J out of DHA was higher. In conclusion, chronic n-6 PUFA deprivation decreases the rate of loss of ARA and increases the rate of loss of DHA in brain phospholipids. Thus, a low n-6 PUFA diet can be used to target brain ARA and DHA metabolism.
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Affiliation(s)
- Lauren E Lin
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Chuck T Chen
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Kayla D Hildebrand
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Zhen Liu
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Kathryn E Hopperton
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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Taha AY, Chang L, Chen M, Rapoport SI, Ramadan E. D2-like receptor activation does not initiate a brain docosahexaenoic acid signal in unanesthetized rats. BMC Neurosci 2014; 15:113. [PMID: 25359512 PMCID: PMC4295280 DOI: 10.1186/1471-2202-15-113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Accepted: 09/23/2014] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND The polyunsaturated fatty acid, docosahexaenoic acid (DHA), participates in neurotransmission involving activation of calcium-independent phospholipase A2 (iPLA2), which is coupled to muscarinic, cholinergic and serotonergic neuroreceptors. Drug induced activation of iPLA2 can be measured in vivo with quantitative autoradiography using 14C-DHA as a probe. The present study used this approach to address whether a DHA signal is produced following dompaminergic (D)2-like receptor activation with quinpirole in rat brain. Unanesthetized rats were infused intravenously with 14C-DHA one minute after saline or quinpirole infusion, and serial blood samples were collected over a 20-minute period to obtain plasma. The animals were euthanized with sodium pentobarbital and their brains excised, coronally dissected and subjected to quantitative autoradiography to derive the regional incorporation coefficient, k*, a marker of DHA signaling. Plasma labeled and unlabeled unesterified DHA concentrations were measured. RESULTS The incorporation coefficient (k*) for DHA did not differ significantly between quinpirole-treated and control rats in any of 81 identified brain regions. Plasma labeled DHA concentration over the 20-minute collection period (input function) and unlabeled unesterified DHA concentration did not differ significantly between the two groups. CONCLUSION These findings demonstrate that D2-like receptor initiated signaling does not involve DHA as a second messenger, and likely does not involve iPLA2 activation.
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Affiliation(s)
- Ameer Y Taha
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bldg. 9, Room 1S126, Bethesda, MD 20892 USA
| | - Lisa Chang
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bldg. 9, Room 1S126, Bethesda, MD 20892 USA
| | - Mei Chen
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bldg. 9, Room 1S126, Bethesda, MD 20892 USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bldg. 9, Room 1S126, Bethesda, MD 20892 USA
| | - Epolia Ramadan
- Brain Physiology and Metabolism Section, Laboratory of Neuroscience, National Institute on Aging, National Institutes of Health, Bldg. 9, Room 1S126, Bethesda, MD 20892 USA
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Coordination of gene expression of arachidonic and docosahexaenoic acid cascade enzymes during human brain development and aging. PLoS One 2014; 9:e100858. [PMID: 24963629 PMCID: PMC4070994 DOI: 10.1371/journal.pone.0100858] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 05/30/2014] [Indexed: 12/19/2022] Open
Abstract
Background The polyunsaturated arachidonic and docosahexaenoic acids (AA and DHA) participate in cell membrane synthesis during neurodevelopment, neuroplasticity, and neurotransmission throughout life. Each is metabolized via coupled enzymatic reactions within separate but interacting metabolic cascades. Hypothesis AA and DHA pathway genes are coordinately expressed and underlie cascade interactions during human brain development and aging. Methods The BrainCloud database for human non-pathological prefrontal cortex gene expression was used to quantify postnatal age changes in mRNA expression of 34 genes involved in AA and DHA metabolism. Results Expression patterns were split into Development (0 to 20 years) and Aging (21 to 78 years) intervals. Expression of genes for cytosolic phospholipases A2 (cPLA2), cyclooxygenases (COX)-1 and -2, and other AA cascade enzymes, correlated closely with age during Development, less so during Aging. Expression of DHA cascade enzymes was less inter-correlated in each period, but often changed in the opposite direction to expression of AA cascade genes. Except for the PLA2G4A (cPLA2 IVA) and PTGS2 (COX-2) genes at 1q25, highly inter-correlated genes were at distant chromosomal loci. Conclusions Coordinated age-related gene expression during the brain Development and Aging intervals likely underlies coupled changes in enzymes of the AA and DHA cascades and largely occur through distant transcriptional regulation. Healthy brain aging does not show upregulation of PLA2G4 or PTGS2 expression, which was found in Alzheimer's disease.
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Rapoport SI. Lithium and the other mood stabilizers effective in bipolar disorder target the rat brain arachidonic acid cascade. ACS Chem Neurosci 2014; 5:459-67. [PMID: 24786695 DOI: 10.1021/cn500058v] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
This Review evaluates the arachidonic acid (AA, 20:4n-6) cascade hypothesis for the actions of lithium and other FDA-approved mood stabilizers in bipolar disorder (BD). The hypothesis is based on evidence in unanesthetized rats that chronically administered lithium, carbamazepine, valproate, or lamotrigine each downregulated brain AA metabolism, and it is consistent with reported upregulated AA cascade markers in post-mortem BD brain. In the rats, each mood stabilizer reduced AA turnover in brain phospholipids, cyclooxygenase-2 expression, and prostaglandin E2 concentration. Lithium and carbamazepine also reduced expression of cytosolic phospholipase A2 (cPLA2) IVA, which releases AA from membrane phospholipids, whereas valproate uncompetitively inhibited in vitro acyl-CoA synthetase-4, which recycles AA into phospholipid. Topiramate and gabapentin, proven ineffective in BD, changed rat brain AA metabolism minimally. On the other hand, the atypical antipsychotics olanzapine and clozapine, which show efficacy in BD, decreased rat brain AA metabolism by reducing plasma AA availability. Each of the four approved mood stabilizers also dampened brain AA signaling during glutamatergic NMDA and dopaminergic D2 receptor activation, while lithium enhanced the signal during cholinergic muscarinic receptor activation. In BD patients, such signaling effects might normalize the neurotransmission imbalance proposed to cause disease symptoms. Additionally, the antidepressants fluoxetine and imipramine, which tend to switch BD depression to mania, each increased AA turnover and cPLA2 IVA expression in rat brain, suggesting that brain AA metabolism is higher in BD mania than depression. The AA hypothesis for mood stabilizer action is consistent with reports that low-dose aspirin reduced morbidity in patients taking lithium, and that high n-3 and/or low n-6 polyunsaturated fatty acid diets, which in rats reduce brain AA metabolism, were effective in BD and migraine patients.
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Affiliation(s)
- Stanley I. Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, Maryland 20892, United States
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Mason JK, Kharotia S, Wiggins AKA, Kitson AP, Chen J, Bazinet RP, Thompson LU. 17β-Estradiol Increases Liver and Serum Docosahexaenoic Acid in Mice Fed Varying Levels of α-Linolenic Acid. Lipids 2014; 49:745-56. [DOI: 10.1007/s11745-014-3913-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 05/11/2014] [Indexed: 01/25/2023]
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Ramadan E, Blanchard H, Cheon Y, Fox MA, Chang L, Chen M, Ma K, Rapoport SI, Basselin M. Transient postnatal fluoxetine leads to decreased brain arachidonic acid metabolism and cytochrome P450 4A in adult mice. Prostaglandins Leukot Essent Fatty Acids 2014; 90:191-7. [PMID: 24529827 PMCID: PMC3981912 DOI: 10.1016/j.plefa.2014.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/19/2014] [Accepted: 01/21/2014] [Indexed: 12/11/2022]
Abstract
Fetal and perinatal exposure to selective serotonin (5-HT) reuptake inhibitors (SSRIs) has been reported to alter childhood behavior, while transient early exposure in rodents is reported to alter their behavior and decrease brain extracellular 5-HT in adulthood. Since 5-HT2A/2C receptor-mediated neurotransmission can involve G-protein coupled activation of cytosolic phospholipase A2 (cPLA2), releasing arachidonic acid (ARA) from synaptic membrane phospholipid, we hypothesized that transient postnatal exposure to fluoxetine would alter brain ARA metabolism in adult mice. Brain ARA incorporation coefficients k* and rates Jin were quantitatively imaged following intravenous [1-(14)C]ARA infusion of unanesthetized adult mice that had been injected daily with fluoxetine (10mg/kg i.p.) or saline during postnatal days P4-P21. Expression of brain ARA metabolic enzymes and other relevant markers also was measured. On neuroimaging, k* and Jin was decreased widely in early fluoxetine- compared to saline-treated adult mice. Of the enzymes measured, cPLA2 activity was unchanged, while Ca(2+)-independent iPLA2 activity was increased. There was a significant 74% reduced protein level of cytochrome P450 (CYP) 4A, which can convert ARA to 20-HETE. Reduced brain ARA metabolism in adult mice transiently exposed to postnatal fluoxetine, and a 74% reduction in CYP4A protein, suggest long-term effects independent of drug presence in brain ARA metabolism, and in CYP4A metabolites. These changes might contribute to reported altered behavior following early SSRI in rodents.
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Affiliation(s)
- Epolia Ramadan
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Helene Blanchard
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Yewon Cheon
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Meredith A Fox
- Laboratory of Clinical Science, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lisa Chang
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Mei Chen
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Kaizong Ma
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Mireille Basselin
- Brain Physiology and Metabolism Section, Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
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Domenichiello AF, Chen CT, Trepanier MO, Stavro PM, Bazinet RP. Whole body synthesis rates of DHA from α-linolenic acid are greater than brain DHA accretion and uptake rates in adult rats. J Lipid Res 2013; 55:62-74. [PMID: 24212299 PMCID: PMC3927474 DOI: 10.1194/jlr.m042275] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Docosahexaenoic acid (DHA) is important for brain function, however, the exact
amount required for the brain is not agreed upon. While it is believed that the
synthesis rate of DHA from α-linolenic acid (ALA) is low, how this
synthesis rate compares with the amount of DHA required to maintain brain DHA
levels is unknown. The objective of this work was to assess whether DHA
synthesis from ALA is sufficient for the brain. To test this, rats consumed a
diet low in n-3 PUFAs, or a diet containing ALA or DHA for 15 weeks. Over the 15
weeks, whole body and brain DHA accretion was measured, while at the end of the
study, whole body DHA synthesis rates, brain gene expression, and DHA uptake
rates were measured. Despite large differences in body DHA accretion, there was
no difference in brain DHA accretion between rats fed ALA and DHA. In rats fed
ALA, DHA synthesis and accretion was 100-fold higher than brain DHA accretion of
rats fed DHA. Also, ALA-fed rats synthesized approximately 3-fold more DHA than
the DHA uptake rate into the brain. This work indicates that DHA synthesis from
ALA may be sufficient to supply the brain.
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Igarashi M, Chang L, Ma K, Rapoport SI. Kinetics of eicosapentaenoic acid in brain, heart and liver of conscious rats fed a high n-3 PUFA containing diet. Prostaglandins Leukot Essent Fatty Acids 2013; 89:403-12. [PMID: 24209500 PMCID: PMC5861380 DOI: 10.1016/j.plefa.2013.09.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 09/07/2013] [Accepted: 09/07/2013] [Indexed: 01/06/2023]
Abstract
Eicosapentaenoic acid (EPA, 20:5n-3), a precursor of docosahexaenoic acid (DHA), may benefit cardiovascular and brain health. Quantifying EPA's in vivo kinetics might elucidate these effects. [1-(14)C]EPA was infused i.v. for 5min in unanesthetized male rats fed a standard EPA-DHA diet. Plasma and microwaved tissue were analyzed. Kinetic parameters were calculated using our compartmental model. At 5min, 31-48% of labeled EPA in brain and heart was oxidized, 7% in liver. EPA incorporation rates from brain and liver precursor EPA-CoA pools into lipids, mainly phospholipids, were 36 and 2529nmol/s/g×10(-4), insignificant for heart. Deacylation-reacylation half-lives were 22h and 38-128min. Conversion rates to DHA equaled 0.65 and 25.1nmol/s/g×10(-4), respectively. The low brain concentration and incorporation rate and high oxidation of EPA suggest that, if EPA has a beneficial effect in brain, it might result from its suppression of peripheral inflammation and hepatic conversion to bioactive DHA.
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Affiliation(s)
- Miki Igarashi
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Building 9, Room 1S126, Bethesda, MD 20892, USA.
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Brain docosahexaenoic acid [DHA] incorporation and blood flow are increased in chronic alcoholics: a positron emission tomography study corrected for cerebral atrophy. PLoS One 2013; 8:e75333. [PMID: 24098376 PMCID: PMC3788756 DOI: 10.1371/journal.pone.0075333] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 08/12/2013] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVE Chronic alcohol dependence has been associated with disturbed behavior, cerebral atrophy and a low plasma concentration of docosahexaenoic acid (DHA, 22∶6n-3), particularly if liver disease is present. In animal models, excessive alcohol consumption is reported to reduce brain DHA concentration, suggesting disturbed brain DHA metabolism. We hypothesized that brain DHA metabolism also is abnormal in chronic alcoholics. METHODS We compared 15 non-smoking chronic alcoholics, studied within 7 days of their last drink, with 22 non-smoking healthy controls. Using published neuroimaging methods with positron emission tomography (PET), we measured regional coefficients (K*) and rates (J(in)) of DHA incorporation from plasma into the brain of each group using [1-(11)C]DHA, and regional cerebral blood flow (rCBF) using [(15)O]water. Data were partial volume error corrected for brain atrophy. Plasma unesterified DHA concentration also was quantified. RESULTS Mean K* for DHA was significantly and widely elevated by 10-20%, and rCBF was elevated by 7%-34%, in alcoholics compared with controls. Unesterified plasma DHA did not differ significantly between groups nor did whole brain J(in), the product of K* and unesterified plasma DHA concentration. DISCUSSION Significantly higher values of K* for DHA in alcoholics indicate increased brain avidity for DHA, thus a brain DHA metabolic deficit vis-à-vis plasma DHA availability. Higher rCBF in alcoholics suggests increased energy consumption. These changes may reflect a hypermetabolic state related to early alcohol withdrawal, or a general brain metabolic change in chronic alcoholics.
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Chen CT, Domenichiello AF, Trépanier MO, Liu Z, Masoodi M, Bazinet RP. The low levels of eicosapentaenoic acid in rat brain phospholipids are maintained via multiple redundant mechanisms. J Lipid Res 2013; 54:2410-22. [PMID: 23836105 PMCID: PMC3735939 DOI: 10.1194/jlr.m038505] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 06/26/2013] [Indexed: 12/19/2022] Open
Abstract
Brain eicosapentaenoic acid (EPA) levels are 250- to 300-fold lower than docosahexaenoic acid (DHA), at least partly, because EPA is rapidly β-oxidized and lost from brain phospholipids. Therefore, we examined if β-oxidation was necessary for maintaining low EPA levels by inhibiting β-oxidation with methyl palmoxirate (MEP). Furthermore, because other metabolic differences between DHA and EPA may also contribute to their vastly different levels, this study aimed to quantify the incorporation and turnover of DHA and EPA into brain phospholipids. Fifteen-week-old rats were subjected to vehicle or MEP prior to a 5 min intravenous infusion of (14)C-palmitate, (14)C-DHA, or (14)C-EPA. MEP reduced the radioactivity of brain aqueous fractions for (14)C-palmitate-, (14)C-EPA-, and (14)C-DHA-infused rats by 74, 54, and 23%, respectively; while it increased the net rate of incorporation of plasma unesterified palmitate into choline glycerophospholipids and phosphatidylinositol and EPA into ethanolamine glycerophospholipids and phosphatidylserine. MEP also increased the synthesis of n-3 docosapentaenoic acid (n-3 DPA) from EPA. Moreover, the recycling of EPA into brain phospholipids was 154-fold lower than DHA. Therefore, the low levels of EPA in the brain are maintained by multiple redundant pathways including β-oxidation, decreased incorporation from plasma unesterified FA pool, elongation/desaturation to n-3 DPA, and lower recycling within brain phospholipids.
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Affiliation(s)
- Chuck T. Chen
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada M5S 3E2; and
| | - Anthony F. Domenichiello
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada M5S 3E2; and
| | - Marc-Olivier Trépanier
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada M5S 3E2; and
| | - Zhen Liu
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada M5S 3E2; and
| | - Mojgan Masoodi
- Nestlé Institute of Health Sciences SA, Campus EPFL, Quartier de l'innovation, bâtiment G, 1015 Lausanne, Switzerland
| | - Richard P. Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada M5S 3E2; and
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Sato Y, Bernier F, Suzuki I, Kotani S, Nakagawa M, Oda Y. Comparative lipidomics of mouse brain exposed to enriched environment. J Lipid Res 2013; 54:2687-96. [PMID: 23833247 DOI: 10.1194/jlr.m038075] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Several studies have shown that housing conditions and environmental exposure to a series of stimuli lead to behavior improvement in several species. While more works have been focused on illustrating changes of the proteome and transcriptome following enriched environment exposure in mice, little has been done to understand changes in the brain metabolome in this paradigm due to the complexity of this type of analysis. In this paper, lipidomics focused on phospholipids and gangliosides were conducted for brain tissues of mice exposed to enriched or impoverished conditions. We optimized previously reported method and established a reliable relative comparison method for phospholipids and gangliosides in brain tissue using prefractionation with weak anion exchange cartridge. We used liquid chromatography mass spectrometry to explore metabolic signatures of the cerebral cortex and hippocampus after confirming the animals had significant memory differences using the fear conditioning paradigm and brain immunohistochemistry. Although both cerebral cortex and hippocampus regions did not show major alterations in ganglioside composition, we found significant differences in a series of phospholipids containing 22:6 fatty acid in the prefrontal cortex, indicating that environmental enrichment and impoverished housing conditions might be a relevant paradigm to study aberrant lipid metabolism of docosahexaenoic acid consumption. Our study highlights the hypothesis-generating potential of lipidomics and identifies novel region-specific lipid changes possibly linked not only to change of memory function in these models, but also to help us better understand how lipid changes may contribute to memory disorders.
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Affiliation(s)
- Yoshiaki Sato
- Eisai Company, Limited, Ibaraki 300-2635, Japan; and
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44
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Taha AY, Trepanier MO, Ciobanu FA, Taha NM, Ahmed M, Zeng Q, Cheuk WI, Ip B, Filo E, Scott BW, Burnham WM, Bazinet RP. A minimum of 3 months of dietary fish oil supplementation is required to raise amygdaloid afterdischarge seizure thresholds in rats--implications for treating complex partial seizures. Epilepsy Behav 2013; 27:49-58. [PMID: 23376336 DOI: 10.1016/j.yebeh.2012.12.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 11/10/2012] [Accepted: 12/08/2012] [Indexed: 12/14/2022]
Abstract
Complex partial seizures, which typically originate in limbic structures such as the amygdala, are often resistant to antiseizure medications. Our goal was to investigate the effects of chronic dietary supplementation with n-3 polyunsaturated fatty acids (PUFAs) derived from fish oil on seizure thresholds in the amygdala, as well as on blood and brain PUFA levels. The acute effects of injected n-3 PUFAs--eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)--were also tested in the maximal pentylenetetrazol (PTZ) seizure model. In amygdala-implanted subjects, fish oil supplementation significantly increased amygdaloid afterdischarge thresholds, as compared with controls at 3, 5, and 7 months after the start of supplementation. Fish oil supplementation also increased serum EPA and DHA concentrations. DHA concentration in the pyriform-amygdala area increased in the fish-oil treated group by 17-34%, but this effect did not reach statistical significance (P=0.065). DHA significantly increased the latency to seizure onset in the PTZ seizure model, whereas EPA had no significant effect. These observations suggest that chronic dietary fish oil supplementation can raise focal amygdaloid seizure thresholds and that this effect is likely mediated by DHA rather than by EPA.
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Affiliation(s)
- Ameer Y Taha
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada M5S 1A8.
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45
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Modi HR, Taha AY, Kim HW, Chang L, Rapoport SI, Cheon Y. Chronic clozapine reduces rat brain arachidonic acid metabolism by reducing plasma arachidonic acid availability. J Neurochem 2013; 124:376-87. [PMID: 23121637 PMCID: PMC3540173 DOI: 10.1111/jnc.12078] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 10/12/2012] [Accepted: 10/29/2012] [Indexed: 12/23/2022]
Abstract
Chronic administration of mood stabilizers to rats down-regulates the brain arachidonic acid (AA) cascade. This down-regulation may explain their efficacy against bipolar disorder (BD), in which brain AA cascade markers are elevated. The atypical antipsychotics, olanzapine (OLZ) and clozapine (CLZ), also act against BD. When given to rats, both reduce brain cyclooxygenase activity and prostaglandin E(2) concentration; OLZ also reduces rat plasma unesterified and esterified AA concentrations, and AA incorporation and turnover in brain phospholipid. To test whether CLZ produces similar changes, we used our in vivo fatty acid method in rats given 10 mg/kg/day i.p. CLZ, or vehicle, for 30 days; or 1 day after CLZ washout. [1-(14) C]AA was infused intravenously for 5 min, arterial plasma was collected and high-energy microwaved brain was analyzed. CLZ increased incorporation coefficients ki * and decreased [corrected] rates J(in,i) of plasma unesterified AA into brain phospholipids. [corrected]. These effects disappeared after washout. Thus, CLZ and OLZ similarly down-regulated kinetics and cyclooxygenase expression of the brain AA cascade, likely by reducing plasma unesterified AA availability. Atypical antipsychotics and mood stabilizers may be therapeutic in BD by down-regulating, indirectly or directly respectively, the elevated brain AA cascade of that disease.
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Affiliation(s)
- Hiren R Modi
- Brain Physiology and Metabolism Section, National Institute on Aging, Laboratory of Neurosciences, National Institutes of Health, Bethesda, MD 20892, USA.
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Martin ML, Barceló-Coblijn G, de Almeida RFM, Noguera-Salvà MA, Terés S, Higuera M, Liebisch G, Schmitz G, Busquets X, Escribá PV. The role of membrane fatty acid remodeling in the antitumor mechanism of action of 2-hydroxyoleic acid. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1405-13. [PMID: 23360770 DOI: 10.1016/j.bbamem.2013.01.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Revised: 12/15/2012] [Accepted: 01/17/2013] [Indexed: 01/08/2023]
Abstract
The synthetic fatty acid 2-hydroxyoleic acid (2OHOA) is a potent antitumor drug that we rationally designed to regulate the membrane lipid composition and structure. The lipid modifications caused by 2OHOA treatments induce important signaling changes that end up with cell death (Terés et al., 2012 [1]). One of these regulatory effects is restoration of sphingomyelin levels, which are markedly lower in cancer cells compared to normal cells (Barceló-Coblijn et al., 2011 [2]). In this study, we report another important regulatory effect of 2OHOA on cancer cell membrane composition: a large increase in 2OHOA levels, accounting for ~15% of the fatty acids present in membrane phospholipids, in human glioma (SF767 and U118) and lung cancer (A549) cells. Concomitantly, we observed marked reductions in oleic acid levels and inhibition of stearoyl-CoA desaturase. The impact of these changes on the biophysical properties of the lipid bilayer was evaluated in liposomes reconstituted from cancer cell membrane lipid extracts. Thus, 2OHOA increased the packing of ordered domains and decreased the global order of the membrane. The present results further support and extend the knowledge about the mechanism of action for 2OHOA, based on the regulation of the membrane lipid composition and structure and subsequent modulation of membrane protein-associated signaling.
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Affiliation(s)
- Maria Laura Martin
- Department of Biology, University of the Balearic Islands, Balearic Islands, Spain
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47
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Rapoport SI. Translational studies on regulation of brain docosahexaenoic acid (DHA) metabolism in vivo. Prostaglandins Leukot Essent Fatty Acids 2013; 88:79-85. [PMID: 22766388 PMCID: PMC3467358 DOI: 10.1016/j.plefa.2012.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Revised: 04/29/2012] [Accepted: 05/01/2012] [Indexed: 01/30/2023]
Abstract
One goal in the field of brain polyunsaturated fatty acid (PUFA) metabolism is to translate the many studies that have been conducted in vitro and in animal models to the clinical setting. Doing so should elucidate the role of PUFAs in the human brain, and effects of diet, drugs, disease and genetics on this role. This review discusses new in vivo radiotracer kinetic and neuroimaging techniques that allow us to do this, with a focus on docosahexaenoic acid (DHA). We illustrate how brain PUFA metabolism is influenced by graded reductions in dietary n-3 PUFA content in unanesthetized rats. We also show how kinetic tracer techniques in rodents have helped to identify mechanisms of action of mood stabilizers used in bipolar disorder, how DHA participates in neurotransmission, and how brain DHA metabolism is regulated by calcium-independent iPLA₂β. In humans, regional rates of brain DHA metabolism can be quantitatively imaged with positron emission tomography following intravenous injection of [1-¹¹C]DHA.
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Affiliation(s)
- Stanley I Rapoport
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Building 9, Room 1S128, Bethesda, MD 20892, USA.
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48
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Ramadan E, Basselin M, Chang L, Chen M, Ma K, Rapoport SI. Chronic lithium feeding reduces upregulated brain arachidonic acid metabolism in HIV-1 transgenic rat. J Neuroimmune Pharmacol 2012; 7:701-13. [PMID: 22760927 PMCID: PMC3478068 DOI: 10.1007/s11481-012-9381-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 06/04/2012] [Indexed: 01/09/2023]
Abstract
HIV-1 transgenic (Tg) rats, a model for human HIV-1 associated neurocognitive disorder (HAND), show upregulated markers of brain arachidonic acid (AA) metabolism with neuroinflammation after 7 months of age. Since lithium decreases AA metabolism in a rat lipopolysaccharide model of neuroinflammation, and may be useful in HAND, we hypothesized that lithium would dampen upregulated brain AA metabolism in HIV-1 Tg rats. Regional brain AA incorporation coefficients k* and rates J ( in ), markers of AA signaling and metabolism, were measured in 81 brain regions using quantitative autoradiography, after intravenous [1-(14) C]AA infusion in unanesthetized 10-month-old HIV-1 Tg and age-matched wildtype rats that had been fed a control or LiCl diet for 6 weeks. k* and J ( in ) for AA were significantly higher in HIV-1 Tg than wildtype rats fed the control diet. Lithium feeding reduced plasma unesterified AA concentration in both groups and J ( in ) in wildtype rats, and blocked increments in k* (19 of 54 regions) and J ( in ) (77 of 81 regions) in HIV-1 Tg rats. These in vivo neuroimaging data indicate that lithium treatment dampened upregulated brain AA metabolism in HIV-1 Tg rats. Lithium may improve cognitive dysfunction and be neuroprotective in HIV-1 patients with HAND through a comparable effect.
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Affiliation(s)
- Epolia Ramadan
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Mireille Basselin
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Lisa Chang
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Mei Chen
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Kaizong Ma
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - Stanley I. Rapoport
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
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49
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Cheon Y, Kim HW, Igarashi M, Modi HR, Chang L, Ma K, Greenstein D, Wohltmann M, Turk J, Rapoport SI, Taha AY. Disturbed brain phospholipid and docosahexaenoic acid metabolism in calcium-independent phospholipase A(2)-VIA (iPLA(2)β)-knockout mice. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1821:1278-86. [PMID: 22349267 PMCID: PMC3393806 DOI: 10.1016/j.bbalip.2012.02.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/25/2012] [Accepted: 02/03/2012] [Indexed: 10/14/2022]
Abstract
Calcium-independent phospholipase A(2) group VIA (iPLA(2)β) releases docosahexaenoic acid (DHA) from phospholipids in vitro. Mutations in the iPLA(2)β gene, PLA2G6, are associated with dystonia-parkinsonism and infantile neuroaxonal dystrophy. To understand the role of iPLA(2)β in brain, we applied our in vivo kinetic method using radiolabeled DHA in 4 to 5-month-old wild type (iPLA(2)β(+/+)) and knockout (iPLA(2)β(-/-)) mice, and measured brain DHA kinetics, lipid concentrations, and expression of PLA(2), cyclooxygenase (COX), and lipoxygenase (LOX) enzymes. Compared to iPLA(2)β(+/+) mice, iPLA(2)β(-/-) mice showed decreased rates of incorporation of unesterified DHA from plasma into brain phospholipids, reduced concentrations of several fatty acids (including DHA) esterified in ethanolamine- and serine-glycerophospholipids, and increased lysophospholipid fatty acid concentrations. DHA turnover in brain phospholipids did not differ between genotypes. In iPLA(2)β(-/-) mice, brain levels of iPLA(2)β mRNA, protein, and activity were decreased, as was the iPLA(2)γ (Group VIB PLA(2)) mRNA level, while levels of secretory sPLA(2)-V mRNA, protein, and activity and cytosolic cPLA(2)-IVA mRNA were increased. Levels of COX-1 protein were decreased in brain, while COX-2 protein and mRNA were increased. Levels of 5-, 12-, and 15-LOX proteins did not differ significantly between genotypes. Thus, a genetic iPLA(2)β deficiency in mice is associated with reduced DHA metabolism, profound changes in lipid-metabolizing enzyme expression (demonstrating lack of redundancy) and of phospholipid fatty acid content of brain (particularly of DHA), which may be relevant to neurologic abnormalities in humans with PLA2G6 mutations.
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Affiliation(s)
- Yewon Cheon
- National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA.
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50
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Igarashi M, Kim HW, Gao F, Chang L, Ma K, Rapoport SI. Fifteen weeks of dietary n-3 polyunsaturated fatty acid deprivation increase turnover of n-6 docosapentaenoic acid in rat-brain phospholipids. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1821:1235-43. [PMID: 22142872 PMCID: PMC3348251 DOI: 10.1016/j.bbalip.2011.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 10/25/2011] [Accepted: 11/02/2011] [Indexed: 11/23/2022]
Abstract
Docosapentaenoic acid (DPAn-6, 22:5n-6) is an n-6 polyunsaturated fatty acid (PUFA) whose brain concentration can be increased in rodents by dietary n-3 PUFA deficiency, which may contribute to their behavioral dysfunction. We used our in vivo intravenous infusion method to see if brain DPAn-6 turnover and metabolism also were altered with deprivation. We studied male rats that had been fed for 15 weeks post-weaning an n-3 PUFA adequate diet containing 4.6% alpha-linolenic acid (α-LNA, 18:3n-3) or a deficient diet (0.2% α-LNA), each lacking docosahexaenoic acid (22:6n-3) and arachidonic acid (AA, 20:4n-6). [1-(14)C]DPAn-6 was infused intravenously for 5min in unanesthetized rats, after which the brain underwent high-energy microwaving, and then was analyzed. The n-3 PUFA deficient compared with adequate diet increased DPAn-6 and decreased DHA concentrations in plasma and brain, while minimally changing brain AA concentration. Incorporation rates of unesterified DPAn-6 from plasma into individual brain phospholipids were increased 5.2-7.7 fold, while turnover rates were increased 2.1-4.7 fold. The observations suggest that increased metabolism and brain concentrations of DPAn-6 and its metabolites, together with a reduced brain DHA concentration, contribute to behavioral and functional abnormalities reported with dietary n-3 PUFA deprivation in rodents. (196 words).
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Affiliation(s)
- Miki Igarashi
- National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
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