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Kanta JM, Lundsgaard AM, Havelund JF, Armour SL, Bæk O, Nguyen DN, Richter EA, Knudsen JG, Kleinert M, Færgeman NJ, Fritzen AM, Kiens B. Metabolic effects of medium-chain triacylglycerol consumption are preserved in obesity. Am J Physiol Endocrinol Metab 2025; 328:E1-E20. [PMID: 39441241 DOI: 10.1152/ajpendo.00234.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Revised: 10/11/2024] [Accepted: 10/15/2024] [Indexed: 10/25/2024]
Abstract
Several health-beneficial effects are associated with intake of medium-chain triacylglycerol (MCT); however, the underlying mechanisms are unknown. Furthermore, it remains uncertain whether the acute metabolic effects of MCT differ between lean individuals and individuals with obesity-and whether these effects are sustained following chronic intake. This study aimed to elucidate the postprandial physiological and metabolic effects of MCT before and after 8 days intake compared with intake of energy-matched triacylglycerol consisting of long-chain fatty acids (long-chain triacylglycerols, LCT) using a randomized cross-over design in lean individuals (n = 8) and individuals with obesity (n = 8). The study revealed that consumption of MCT increased ketogenesis and metabolic rate while lowering blood glucose levels over 5 h. The hypoglycemic action of MCT intake was accompanied by a concomitant transient increase in plasma insulin and glucagon levels. Interestingly, the effects on ketogenesis, metabolic rate, and glycemia were preserved in individuals with obesity and sustained after 8 days of daily supplementation. Lipidomic plasma analysis in lean individuals (n = 4) showed that a part of the ingested MCT bypasses the liver and enters the systemic circulation as medium-chain fatty acids (MCFAs). The findings suggest that MCFAs, along with ketone bodies from the liver, may act as signaling molecules and/or substrates in the peripheral tissues, thereby contributing to the effects of MCT intake. In summary, these findings underscore the health benefits of MCT in metabolically compromised individuals after daily supplementation. Moreover, we uncover novel aspects of MCFA biology, providing insights into how these fatty acids orchestrate physiological effects in humans.NEW & NOTEWORTHY We reveal that medium-chain triacylglycerol (MCT) intake increases postprandial ketogenesis and metabolic rate and reduces plasma glucose levels in humans. Notably, these responses persist in individuals with obesity and are maintained following chronic MCT supplementation. Some medium-chain fatty acids entered the circulation, suggesting that these, together with ketone bodies, act as signaling molecules/substrates in peripheral tissues. The findings highlight health beneficial effects of dietary MCT in individuals with obesity and reveal new insights into lipid biology.
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Affiliation(s)
- Josephine M Kanta
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
| | - Anne-Marie Lundsgaard
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
- Novo Nordisk A/S, Søborg, Denmark
| | - Jesper F Havelund
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Sara L Armour
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Denmark
| | - Ole Bæk
- Section for Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
- Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Duc Ninh Nguyen
- Section for Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Erik A Richter
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
| | - Jakob G Knudsen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Denmark
| | - Maximilian Kleinert
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
- Muscle Physiology and Metabolism Group, German Institute of Human Nutrition (DIfE), Potsdam-Rehbruecke, Germany
| | - Nils J Færgeman
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Andreas M Fritzen
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Medical and Health Sciences, University of Copenhagen, Denmark
| | - Bente Kiens
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
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Pinheiro RRS, Watanabe PH, Araújo LRS, Mendonça IBD, Sales JJDM, Santos MEC, Pascoal LAF, Guerra RR, Almeida JMDS, Freitas ER. Structured lipids from fish viscera and coconut oils improve weight gain and intestinal morphology of piglets at nursery phase. Trop Anim Health Prod 2024; 56:403. [PMID: 39652263 DOI: 10.1007/s11250-024-04235-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Accepted: 11/13/2024] [Indexed: 12/20/2024]
Abstract
Five metabolism assays were performed to determine the metabolizable energy (ME) content of soybean oil, coconut oil, fish viscera oil, physical mixture of coconut oil and fish viscera oil (3:2, in kg: kg) and structured lipid prepared from interesterification of fish viscera oil and coconut oil (3: 2, in kg: kg), and one assay to evaluate the effects of including these lipid sources in piglet diets on performance, digestibility of diets, incidence of diarrhea and intestinal morphometry at nursery phase. Soybean, coconut, fish viscera, physical mixture and structured lipid oils showed ME values of 8239, 8199, 8839, 8268 and 8523 kcal/kg DM respectively. In the performance trial, a total of 90 piglets with 23 days of age were distributed among 5 diets, differing in the lipid source used (soybean oil, coconut oil, fish viscera oil, physical mixture or structured lipid). Piglets fed diet containing structured lipid showed better feed conversion, higher duodenal goblet cell number and jejunal absorption area (P < 0.05), with better digestibility of ether extract and energy of diets. Interesterification of lipid sources such as coconut oil and fish viscera oil improves intestinal morphology, positively influencing the performance of piglets at nursery phase.
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Affiliation(s)
| | | | | | | | | | | | | | - Ricardo Romão Guerra
- Departamento de Ciências Veterinárias, Universidade Federal da Paraíba, Areia, Brazil
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Zhang J, Zang X, Jiao P, Wu J, Meng W, Zhao L, Lv Z. Alterations of Ceramides, Acylcarnitines, GlyceroLPLs, and Amines in NSCLC Tissues. J Proteome Res 2024; 23:4343-4358. [PMID: 39317643 DOI: 10.1021/acs.jproteome.4c00344] [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] [Indexed: 09/26/2024]
Abstract
Abnormal lipid metabolism plays an important role in cancer development. In this study, nontargeted lipidomic study on 230 tissue specimens from 79 nonsmall cell lung cancer (NSCLC) patients was conducted using ultraperformance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS). Downregulation of sphingosine and medium-long-chain ceramides and short-medium-chain acylcarnitine, upregulation of long-chain acylcarnitine C20:0, and enhanced histamine methylation were revealed in NSCLC tissues. Compared with paired noncancerous tissues, adenocarcinoma (AC) tissues had significantly decreased levels of sphingosine, medium-long-chain ceramides (Cer d18:1/12:0 and Cer d16:1/14:0, Cer d18:0/16:0, Cer d18:1/16:0, Cer d18:2/16:0, Cer d18:2/18:0), short-medium-chain (C2-C16) acylcarnitines, LPC 20:0 and LPC 22:1, and significantly increased levels of the long-chain acylcarnitine C20:0, LPC 16:0, LPC P-16:0, LPC 20:1, LPC 20:2, glyceroPC, LPE 16:0, and LPE 18:2. In squamous cell carcinoma (SCC) tissues, sphingosine, Cer d18:2/16:0 and Cer d18:2/18:0, and short-medium-chain acylcarnitines had significantly lower levels, while long-chain acylcarnitines (C20:0, and C22:0 or C22:0 M), LPC 20:1, LPC 20:2, and N1,N12-diacetylspermine had significantly higher levels compared to controls. In AC and SCC tissues, the levels of LPG 18:0, LPG 18:1, and LPS 18:1 were significantly decreased, while the levels of ceramide-1-phosphate (C1P) d18:0/3:0 or LPE P-16:0, N1-acetylspermidine, and 1-methylhistamine were significantly increased than controls. Furthermore, an orthogonal partial least-squares-discriminant analysis (OPLS-DA) model based on a 4-lipid panel was established, showing good discrimination ability between cancerous and noncancerous tissues.
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Affiliation(s)
- Jie Zhang
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, P. R. China
| | - Xiaoling Zang
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, P. R. China
- Qingdao Marine Science and Technology Center, Qingdao, Shandong 266235, P. R. China
| | - Peng Jiao
- Department of Thoracic Surgery, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing 100730, P. R. China
| | - Jiangyu Wu
- Department of Thoracic Surgery, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing 100730, P. R. China
| | - Wei Meng
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, P. R. China
| | - Lizhen Zhao
- College of Physics, Qingdao University, Qingdao, Shandong 266071, P. R. China
| | - Zhihua Lv
- School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, P. R. China
- Qingdao Marine Science and Technology Center, Qingdao, Shandong 266235, P. R. China
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Nishida R, Nukaga S, Kawahara I, Miyagawa Y, Goto K, Nakashima C, Luo Y, Sasaki T, Fujii K, Ohmori H, Ogata R, Mori S, Fujiwara-Tani R, Kuniyasu H. Differential Effects of Three Medium-Chain Fatty Acids on Mitochondrial Quality Control and Skeletal Muscle Maturation. Antioxidants (Basel) 2024; 13:821. [PMID: 39061890 PMCID: PMC11273902 DOI: 10.3390/antiox13070821] [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: 06/05/2024] [Revised: 07/03/2024] [Accepted: 07/07/2024] [Indexed: 07/28/2024] Open
Abstract
Nutritional interventions are one focus of sarcopenia treatment. As medium-chain fatty acids (MCFAs) are oxidized in the mitochondria and produce energy through oxidative phosphorylation (OXPHOS), they are key parts of nutritional interventions. We investigated the in vitro effects of three types of MCFA, caprylic acid (C8), capric acid (C10), and lauric acid (C12), in skeletal muscle cells. Compared with C10 and C12, C8 promoted mitophagy through the phosphatase and tensin homolog (PTEN)-induced kinase 1-Parkin pathway and increased the expression of peroxisome proliferator-activated receptor gamma coactivator 1-α and dynamin-related protein 1 to reduce mitochondrial oxidative stress and promote OXPHOS. Furthermore, the expression of myogenic differentiation 1 and myosin heavy chain increased in myotubes, thus promoting muscle differentiation and maturation. These results suggest that C8 improves mitochondrial quality and promotes skeletal muscle maturation; in contrast, C10 and C12 poorly promoted mitochondrial quality control and oxidative stress and suppressed energy production. Future animal experiments are required to establish the usefulness of C8 for nutritional interventions for sarcopenia.
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Grants
- 23K16547 Ministry of Education, Culture, Sports, Science and Technology
- 22K17655 Ministry of Education, Culture, Sports, Science and Technology
- 19K16564 Ministry of Education, Culture, Sports, Science and Technology
- 20K21659 Ministry of Education, Culture, Sports, Science and Technology
- 21K06926 Ministry of Education, Culture, Sports, Science and Technology
- 22K11423 Ministry of Education, Culture, Sports, Science and Technology
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Hiroki Kuniyasu
- Department of Molecular Pathology, Nara Medical University, 840 Shijo-cho, Kashihara 634-8521, Japan; (R.N.); (S.N.); (I.K.); (Y.M.); (K.G.); (C.N.); (Y.L.); (T.S.); (K.F.); (H.O.); (R.O.); (S.M.); (R.F.-T.)
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Maruyama T, Matsui S, Kobayashi R, Horii T, Oguri Y, Tsuzuki S, Horie T, Ono K, Hatada I, Sasaki T. Medium-chain triglyceride-specific appetite is regulated by the β-oxidation of medium-chain fatty acids in the liver. Am J Physiol Endocrinol Metab 2024; 326:E735-E746. [PMID: 38597830 DOI: 10.1152/ajpendo.00031.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 03/28/2024] [Accepted: 03/31/2024] [Indexed: 04/11/2024]
Abstract
Most studies on fat appetite have focused on long-chain triglycerides (LCTs) due to their obesogenic properties. Medium-chain triglycerides (MCTs), conversely, exhibit antiobesogenic effects; however, the regulation of MCT intake remains elusive. Here, we demonstrate that mice can distinguish between MCTs and LCTs, and the specific appetite for MCTs is governed by hepatic β-oxidation. We generated liver-specific medium-chain acyl-CoA dehydrogenase (MCAD)-deficient (MCADL-/-) mice and analyzed their preference for MCT and LCT solutions using glyceryl trioctanoate (C8-TG), glyceryl tridecanoate (C10-TG), corn oil, and lard oil in two-bottle choice tests conducted over 8 days. In addition, we used lick microstructure analyses to evaluate the palatability and appetite for MCT and LCT solutions. Finally, we measured the expression levels of genes associated with fat ingestion (Galanin, Qrfp, and Nmu) in the hypothalamus 2 h after oral gavage of fat. Compared with control mice, MCADL-/- mice exhibited a significantly reduced preference for MCT solutions, with no alteration in the preference for LCTs. Lick analysis revealed that MCADL-/- mice displayed a significantly decreased appetite for MCT solutions only while the palatability of both MCT and LCT solutions remained unaffected. Hypothalamic Galanin expression in control mice was elevated by oral gavage of C8-TG but not by LCTs, and this response was abrogated in MCADL-/- mice. In summary, our data suggest that hepatic β-oxidation is required for MCT-specific appetite but not for LCT-specific appetite. The induction of hypothalamic galanin upon MCT ingestion, dependent on hepatic β-oxidation, could be involved in the regulation of MCT-specific appetite.NEW & NOTEWORTHY Whether and how medium-chain triglyceride (MCT) intake is regulated remains unknown. Here, we showed that mice can discriminate between MCTs and LCTs. Hepatic β-oxidation participates in MCT-specific appetite, and hypothalamic galanin may be one of the factors that regulate MCT intake. Because of the antiobesity effects of MCTs, studying MCT-specific appetite may help combat obesity by promoting the intake of MCTs instead of LCTs.
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Affiliation(s)
- Tsugunori Maruyama
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Sho Matsui
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Ryosuke Kobayashi
- Laboratory of Genome Science, Biosignal Genome Resource Center, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Takuro Horii
- Laboratory of Genome Science, Biosignal Genome Resource Center, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Yasuo Oguri
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Satoshi Tsuzuki
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takahiro Horie
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Koh Ono
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Izuho Hatada
- Laboratory of Genome Science, Biosignal Genome Resource Center, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
- Viral Vector Core, Gunma University Initiative for Advanced Research, Maebashi, Japan
| | - Tsutomu Sasaki
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
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Babcock SJ, Houten SM, Gillingham MB. A review of fatty acid oxidation disorder mouse models. Mol Genet Metab 2024; 142:108351. [PMID: 38430613 PMCID: PMC11073919 DOI: 10.1016/j.ymgme.2024.108351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 03/05/2024]
Abstract
Fatty acid oxidation disorders (FAODs) are a family of rare, genetic disorders that affect any part of the fatty acid oxidation pathway. Patients present with severe phenotypes, such as hypoketotic hypoglycemia, cardiomyopathy, and rhabdomyolysis, and currently manage these symptoms by the avoidance of fasting and maintaining a low-fat, high-carbohydrate diet. Because knowledge about FAODs is limited due to the small number of patients, rodent models have been crucial in learning more about these disorders, particularly in studying the molecular mechanisms involved in different phenotypes and in evaluating treatments for patients. The purpose of this review is to present the different FAOD mouse models and highlight the benefits and limitations of using these models. Specifically, we discuss the phenotypes of the available FAOD mouse models, the potential molecular causes of prominent FAOD phenotypes that have been studied using FAOD mouse models, and how FAOD mouse models have been used to evaluate treatments for patients.
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Affiliation(s)
- Shannon J Babcock
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA.
| | - Sander M Houten
- Deparment of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Melanie B Gillingham
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA
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Gerrard SD, Yonke JA, McMillan RP, Sunny NE, El-Kadi SW. Medium-Chain Fatty Acid Feeding Reduces Oxidation and Causes Panacinar Steatosis in Livers of Neonatal Pigs. J Nutr 2024; 154:908-920. [PMID: 38253226 DOI: 10.1016/j.tjnut.2024.01.023] [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: 11/16/2023] [Revised: 01/10/2024] [Accepted: 01/19/2024] [Indexed: 01/24/2024] Open
Abstract
BACKGROUND Medium-chain fatty acids (MCFAs) are commonly used to enhance the caloric content of infant formulas. We previously reported that pigs fed MCFA developed hepatic steatosis when compared to those fed isocaloric long-chain fatty acid (LCFA) rich formula. OBJECTIVES The objectives of this study were to investigate: 1) whether MCFA and LCFA feeding affect hepatic fatty acid oxidation, and 2) how fat type alters the expression of hepatic fatty acid metabolic genes. METHODS Twenty-six, 7-d-old pigs were fed a low-energy control (CONT) formula, or 2 isocaloric high-energy formulas rich in LCFA or MCFA for 22 days. Livers were collected for examining ex vivo fatty acid oxidation, fatty acid content, and mRNA expression of fatty acid metabolic genes. RESULTS Liver fat was 20% for pigs in the MCFA compared with 2.9% and 4.6% for those in the CONT and LCFA groups (P < 0.05). MCFA-fed pigs had greater amounts of hepatic laurate, myristate, palmitate, and palmitoleate (14, 34, 49, and 9.3 mg · g-1) than those fed LCFA and CONT (1.8, 1.9, 19, 1.5 mg · g-1) formulas (P ≤ 0.05). Hepatic laurate and palmitate oxidation was reduced for pigs fed MCFA (29 mmol · mg-1 · h-1) compared with those fed CONT (54 mmol · mg-1 · h-1) and LCFA (51 mmol · mg-1 · h-1) formulas (P < 0.05). Expression of fatty acid synthase 3 (FASN-3), fatty acid binding protein 1 (FABP-1), and acetyl-CoA carboxylase 1 (ACACA-1) were 8-, 6-, and 2-fold greater for pigs in the MCFA than those in the LCFA and CONT groups (P < 0.05). CONCLUSIONS Feeding MCFA resulted in hepatic steatosis compared with an isocaloric formula rich in LCFA. Steatosis occurred concomitantly with reduced fatty acid oxidation but greater mRNA expression of fatty acid synthetic and catabolic genes.
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Affiliation(s)
- Samuel D Gerrard
- School of Animal Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Joseph A Yonke
- School of Animal Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Ryan P McMillan
- Virginia Tech Metabolic Phenotyping Core, Virginia Tech, Blacksburg, VA, United States
| | - Nishanth E Sunny
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, United States
| | - Samer W El-Kadi
- School of Animal Sciences, Virginia Tech, Blacksburg, VA, United States.
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Singh C. Systems levels analysis of lipid metabolism in oxygen-induced retinopathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.21.568200. [PMID: 38045301 PMCID: PMC10690220 DOI: 10.1101/2023.11.21.568200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Hyperoxia induces glutamine-fueled anaplerosis in the Muller cells, endothelial cells, and retinal explants. Anaplerosis takes away glutamine from the biosynthetic pathway to the energy-producing TCA cycle. This process depletes biosynthetic precursors from newly proliferating endothelial cells. The induction of anaplerosis in the hyperoxic retina is a compensatory response, either to decreased glycolysis or decreased flux from glycolysis to the TCA cycle. We hypothesized that by providing substrates that feed into TCA, we could reverse or prevent glutamine-fueled anaplerosis, thereby abating the glutamine wastage for energy generation. Using an oxygen-induced retinopathy (OIR) mouse model, we first compared the difference in fatty acid metabolism between OIR-resistant BALB/cByJ and OIR susceptible C57BL/6J strains to understand if these strains exhibit metabolic difference that protects BALB/cByJ from the hyperoxic conditions and prevents their vasculature in oxygen-induced retinopathy model. Based on our findings from the metabolic comparison between two mouse strains, we hypothesized that the medium-chain fatty acid, octanoate, can feed into the TCA and serve as an alternative energy source in response to hyperoxia. Our systems levels analysis of OIR model shows that the medium chain fatty acid can serve as an alternative source to feed TCA. We here, for the first time, demonstrate that the retina can use medium-chain fatty acid octanoate to replenish TCA in normoxic and at a higher rate in hyperoxic conditions.
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