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He J, Chen Y, Zhong W, Jun L, Chen D, Cheng H, Mei W. Insufficient secretion of pancreatic FGF21 is the toxicological mechanism and therapeutic target of asparaginase-associated pancreatitis. Toxicol Appl Pharmacol 2024; 485:116920. [PMID: 38582373 DOI: 10.1016/j.taap.2024.116920] [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: 02/26/2024] [Revised: 03/19/2024] [Accepted: 03/31/2024] [Indexed: 04/08/2024]
Abstract
Asparaginase-associated pancreatitis (AAP) is a severe and potentially life-threatening drug-induced pancreas targeted toxicity in the combined chemotherapy of acute lymphoblastic leukemia among children and adolescents. The toxicological mechanism of AAP is not yet clear, and there are no effective preventive and treatment measures available clinically. Fibroblast growth factor 21 (FGF21) is a secretory hormone that regulates lipid, glucose, and energy metabolism balance. Acinar tissue is the main source of pancreatic FGF21 protein and plays an important role in maintaining pancreatic metabolic balance. In this study, we found that the decrease of FGF21 in pancreas is closely related to AAP. Pegaspargase (1 IU/g) induces widespread edema and inflammatory infiltration in the pancreas of rats/mice. The specific expression of FGF21 in the acinar tissue of AAP rats was significantly downregulated. Asparaginase caused dysregulation of the ATF4/ATF3/FGF21 axis in acinar tissue or cells, and thus mediated the decrease of FGF21. It greatly activated ATF3 in the acinar, which competed with ATF4 for the Fgf21 promoter, thereby inhibiting the expression of FGF21. Pharmacological replacement of FGF21 (1 mg/kg) or PERK inhibitors (GSK2656157, 25 mg/kg) can significantly mitigate the pancreatic tissue damage and reduce markers of inflammation associated with AAP, representing potential strategies for the prevention and treatment of AAP.
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Affiliation(s)
- Jiang He
- School of Pharmacy, Anhui University of Traditional Chinese Medicine, Hefei 230012, China; Department of Pharmacy, Children's Hospital of Soochow University, Suzhou 215000
| | - Yajing Chen
- Department of Pharmacy, Children's Hospital of Soochow University, Suzhou 215000
| | - Wen Zhong
- Department of Pharmacy, Children's Hospital of Soochow University, Suzhou 215000
| | - Lu Jun
- Department of Pharmacy, Children's Hospital of Soochow University, Suzhou 215000
| | - Dong Chen
- Department of Pharmacy, Children's Hospital of Soochow University, Suzhou 215000
| | - Hui Cheng
- School of Pharmacy, Anhui University of Traditional Chinese Medicine, Hefei 230012, China
| | - Wang Mei
- School of Pharmacy, Anhui University of Traditional Chinese Medicine, Hefei 230012, China; Department of Pharmacy, Children's Hospital of Soochow University, Suzhou 215000.
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2
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Levy JL, Mirek ET, Rodriguez EM, Zalma B, Burns J, Jonsson WO, Sampath H, Staschke KA, Wek RC, Anthony TG. GCN2 is required to maintain core body temperature in mice during acute cold. Am J Physiol Endocrinol Metab 2023; 325:E624-E637. [PMID: 37792040 PMCID: PMC10864021 DOI: 10.1152/ajpendo.00181.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/01/2023] [Accepted: 09/29/2023] [Indexed: 10/05/2023]
Abstract
Nonshivering thermogenesis in rodents requires macronutrients to fuel the generation of heat during hypothermic conditions. In this study, we examined the role of the nutrient sensing kinase, general control nonderepressible 2 (GCN2) in directing adaptive thermogenesis during acute cold exposure in mice. We hypothesized that GCN2 is required for adaptation to acute cold stress via activation of the integrated stress response (ISR) resulting in liver production of FGF21 and increased amino acid transport to support nonshivering thermogenesis. In alignment with our hypothesis, female and male mice lacking GCN2 failed to adequately increase energy expenditure and veered into torpor. Mice administered a small molecule inhibitor of GCN2 were also profoundly intolerant to acute cold stress. Gcn2 deletion also impeded liver-derived FGF21 but in males only. Within the brown adipose tissue (BAT), acute cold exposure increased ISR activation and its transcriptional execution in males and females. RNA sequencing in BAT identified transcripts that encode actomyosin mechanics and transmembrane transport as requiring GCN2 during cold exposure. These transcripts included class II myosin heavy chain and amino acid transporters, critical for maximal thermogenesis during cold stress. Importantly, Gcn2 deletion corresponded with higher circulating amino acids and lower intracellular amino acids in the BAT during cold stress. In conclusion, we identify a sex-independent role for GCN2 activation to support adaptive thermogenesis via uptake of amino acids into brown adipose.NEW & NOTEWORTHY This paper details the discovery that GCN2 activation is required in both male and female mice to maintain core body temperature during acute cold exposure. The results point to a novel role for GCN2 in supporting adaptive thermogenesis via amino acid transport and actomyosin mechanics in brown adipose tissue.
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Affiliation(s)
- Jordan L Levy
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Emily T Mirek
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Esther M Rodriguez
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Brian Zalma
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Jeffrey Burns
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - William O Jonsson
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Harini Sampath
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Kirk A Staschke
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Indiana University Melvin and Bren Simon Comprehensive Cancer Center, Indianapolis, Indiana, United States
| | - Ronald C Wek
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Indiana University Melvin and Bren Simon Comprehensive Cancer Center, Indianapolis, Indiana, United States
| | - Tracy G Anthony
- Department of Nutritional Sciences, New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey, United States
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Tsai CY, Saito T, Sarangdhar M, Abu-El-Haija M, Wen L, Lee B, Yu M, Lipata DA, Manohar M, Barakat MT, Contrepois K, Tran TH, Theoret Y, Bo N, Ding Y, Stevenson K, Ladas EJ, Silverman LB, Quadro L, Anthony TG, Jegga AG, Husain SZ. A systems approach points to a therapeutic role for retinoids in asparaginase-associated pancreatitis. Sci Transl Med 2023; 15:eabn2110. [PMID: 36921036 PMCID: PMC10205044 DOI: 10.1126/scitranslmed.abn2110] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 02/22/2023] [Indexed: 03/17/2023]
Abstract
Among drug-induced adverse events, pancreatitis is life-threatening and results in substantial morbidity. A prototype example is the pancreatitis caused by asparaginase, a crucial drug used to treat acute lymphoblastic leukemia (ALL). Here, we used a systems approach to identify the factors affecting asparaginase-associated pancreatitis (AAP). Connectivity Map analysis of the transcriptomic data showed that asparaginase-induced gene signatures were potentially reversed by retinoids (vitamin A and its analogs). Analysis of a large electronic health record database (TriNetX) and the U.S. Federal Drug Administration Adverse Events Reporting System demonstrated a reduction in AAP risk with concomitant exposure to vitamin A. Furthermore, we performed a global metabolomic screening of plasma samples from 24 individuals with ALL who developed pancreatitis (cases) and 26 individuals with ALL who did not develop pancreatitis (controls), before and after a single exposure to asparaginase. Screening from this discovery cohort revealed that plasma carotenoids were lower in the cases than in controls. This finding was validated in a larger external cohort. A 30-day dietary recall showed that the cases received less dietary vitamin A than the controls did. In mice, asparaginase administration alone was sufficient to reduce circulating and hepatic retinol. Based on these data, we propose that circulating retinoids protect against pancreatic inflammation and that asparaginase reduces circulating retinoids. Moreover, we show that AAP is more likely to develop with reduced dietary vitamin A intake. The systems approach taken for AAP provides an impetus to examine the role of dietary vitamin A supplementation in preventing or treating AAP.
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Affiliation(s)
- Cheng-Yu Tsai
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
| | - Toshie Saito
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
| | - Mayur Sarangdhar
- Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, 45229, USA
- Division of Oncology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
| | - Maisam Abu-El-Haija
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
- Division of Pediatric Gastroenterology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, 45229, USA
| | - Li Wen
- Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100006, China
| | - Bomi Lee
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
| | - Mang Yu
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
| | - Den A. Lipata
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
| | - Murli Manohar
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
| | - Monique T. Barakat
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
- Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University, Palo Alto, CA, 94304, USA
| | - Kévin Contrepois
- Department of Genetics, School of Medicine, Stanford University, Palo Alto, CA, 94304, USA
| | - Thai Hoa Tran
- Division of Pediatric Hematology Oncology, Charles-Bruneau Cancer Center, CHU Sainte-Justine, Montreal, QC, H3T 1C5, Canada
| | - Yves Theoret
- Département Clinique de Médecine de Laboratoire, Secteur Pharmacologie Clinique, Optilab Montréal - CHU Sainte-Justine, Montreal, H3T 1C5, Canada
| | - Na Bo
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, 15261, USA
| | - Ying Ding
- Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, 15261, USA
| | - Kristen Stevenson
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA
| | - Elena J. Ladas
- Division of Pediatric Hematology/Oncology/Stem Cell Transplant, Columbia University Irving Medical Center, New York, NY, 10032, USA
- Institute of Human Nutrition, Columbia University, New York, NY, 10032, USA
| | - Lewis B. Silverman
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA
- Division of Pediatric Hematology-Oncology, Boston, Children’s Hospital, Boston, MA, 02115, USA
| | - Loredana Quadro
- Department of Food Science, Rutgers Center for Lipid Research and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Tracy G. Anthony
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Anil G. Jegga
- Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
| | - Sohail Z. Husain
- Division of Pediatric Gastroenterology, Department of Pediatrics, Stanford University, Palo Alto, CA, 94304, USA
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Growth-Promoting Effects of Zhenqi Granules on Finishing Pigs. Animals (Basel) 2022; 12:ani12243521. [PMID: 36552440 PMCID: PMC9774107 DOI: 10.3390/ani12243521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/09/2022] [Accepted: 12/10/2022] [Indexed: 12/15/2022] Open
Abstract
Developing nonantibiotic livestock growth promoters attracts intensive interest in the post-antibiotic era. In this study, we investigated the growth-promoting efficacy of Zhenqi granules (ZQ) in pigs and further explored the possible mechanisms by transcriptomics analysis. Weaned piglets (52 days old with an average body weight of 17.92 kg) were fed with diets supplemented with different doses of ZQ (0 g/kg, 1 g/kg, and 2 g/kg) for 30 days and continued observations for an additional 32 days after removing ZQ from the diets. Compared with the control group, the average daily gain, carcass weight, average back fat thickness, and fat meat percentage of the group supplemented with 1 g/kg of ZQ showed a significant increase, and the feed/gain ratio was lower. The group supplemented with 2 g/kg of ZQ also showed a significant increase in average daily gain and average backfat thickness. A transcriptomics analysis revealed that the supplementation of ZQ at 1 g/kg upregulated the expression of genes related to collagen biosynthesis and lipid biosynthesis in skeletal muscle and liver. This effect was primarily through upregulating the mRNA levels of structural proteins and lipid-related enzymes. This study demonstrates the growth-promoting efficacy of ZQ and provides some insights of the mechanism of growth promotion.
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Jonsson WO, Mirek ET, Wek RC, Anthony TG. Activation and execution of the hepatic integrated stress response by dietary essential amino acid deprivation is amino acid specific. FASEB J 2022; 36:e22396. [PMID: 35690926 PMCID: PMC9204950 DOI: 10.1096/fj.202200204rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/16/2022] [Accepted: 05/24/2022] [Indexed: 12/30/2022]
Abstract
Dietary removal of an essential amino acid (EAA) triggers the integrated stress response (ISR) in liver. Herein, we explored the mechanisms that activate the ISR and execute changes in transcription and translation according to the missing EAA. Wild‐type mice and mice lacking general control nonderepressible 2 (Gcn2) were fed an amino acid complete diet or a diet devoid of either leucine or sulfur amino acids (methionine and cysteine). Serum and liver leucine concentrations were significantly reduced within the first 6 h of feeding a diet lacking leucine, corresponding with modest, GCN2‐dependent increases in Atf4 mRNA translation and induction of selected ISR target genes (Fgf21, Slc7a5, Slc7a11). In contrast, dietary removal of the sulfur amino acids lowered serum methionine, but not intracellular methionine, and yet hepatic mRNA abundance of Atf4, Fgf21, Slc7a5, Slc7a11 substantially increased regardless of GCN2 status. Liver tRNA charging levels did not correlate with intracellular EAA concentrations or GCN2 status and remained similar to mice fed a complete diet. Furthermore, loss of Gcn2 increased the occurrence of ribosome collisions in liver and derepressed mechanistic target of rapamycin complex 1 signal transduction, but these changes did not influence execution of the ISR. We conclude that ISR activation is directed by intracellular EAA concentrations, but ISR execution is not. Furthermore, a diet devoid of sulfur amino acids does not require GCN2 for the ISR to execute changes to the transcriptome.
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Affiliation(s)
- William O Jonsson
- Department of Nutritional Sciences, School of Environmental and Biological Sciences, New Jersey Institute for Food, Nutrition, and Health, Rutgers University, New Brunswick, New Jersey, USA
| | - Emily T Mirek
- Department of Nutritional Sciences, School of Environmental and Biological Sciences, New Jersey Institute for Food, Nutrition, and Health, Rutgers University, New Brunswick, New Jersey, USA
| | - Ronald C Wek
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Tracy G Anthony
- Department of Nutritional Sciences, School of Environmental and Biological Sciences, New Jersey Institute for Food, Nutrition, and Health, Rutgers University, New Brunswick, New Jersey, USA
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6
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Kosakamoto H, Okamoto N, Aikawa H, Sugiura Y, Suematsu M, Niwa R, Miura M, Obata F. Sensing of the non-essential amino acid tyrosine governs the response to protein restriction in Drosophila. Nat Metab 2022; 4:944-959. [PMID: 35879463 DOI: 10.1038/s42255-022-00608-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 06/15/2022] [Indexed: 11/08/2022]
Abstract
The intake of dietary protein regulates growth, metabolism, fecundity and lifespan across various species, which makes amino acid (AA)-sensing vital for adaptation to the nutritional environment. The general control nonderepressible 2 (GCN2)-activating transcription factor 4 (ATF4) pathway and the mechanistic target of rapamycin complex 1 (mTORC1) pathway are involved in AA-sensing. However, it is not fully understood which AAs regulate these two pathways in living animals and how they coordinate responses to protein restriction. Here we show in Drosophila that the non-essential AA tyrosine (Tyr) is a nutritional cue in the fat body necessary and sufficient for promoting adaptive responses to a low-protein diet, which entails reduction of protein synthesis and mTORC1 activity and increased food intake. This adaptation is regulated by dietary Tyr through GCN2-independent induction of ATF4 target genes in the fat body. This study identifies the Tyr-ATF4 axis as a regulator of the physiological response to a low-protein diet and sheds light on the essential function of a non-essential nutrient.
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Affiliation(s)
- Hina Kosakamoto
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- RIKEN Center for Biosystems and Dynamics Research, Kobe, Japan
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan
| | - Naoki Okamoto
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan
| | - Hide Aikawa
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Yuki Sugiura
- Department of Biochemistry, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Ryusuke Niwa
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan
| | - Masayuki Miura
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Fumiaki Obata
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
- RIKEN Center for Biosystems and Dynamics Research, Kobe, Japan.
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan.
- Laboratory of Molecular Cell Biology and Development, Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
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7
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Kumar GVN, Hoshitsuki K, Rathod S, Ramsey MJ, Kokai L, Kershaw EE, Xie W, Fernandez CA. Mechanistic studies of PEG-asparaginase-induced liver injury and hepatic steatosis in mice. Acta Pharm Sin B 2021; 11:3779-3790. [PMID: 35024306 PMCID: PMC8727916 DOI: 10.1016/j.apsb.2021.11.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/24/2021] [Accepted: 11/25/2021] [Indexed: 01/19/2023] Open
Abstract
PEGylated-l-asparaginase (PEG-ASNase) is a chemotherapeutic agent used to treat pediatric acute lymphoblastic leukemia (ALL). Its use is avoided in adults due to its high risk of liver injury including hepatic steatosis, with obesity and older age considered risk factors of the injury. Our study aims to elucidate the mechanism of PEG-ASNase-induced liver injury. Mice received 1500 U/kg of PEG-ASNase and were sacrificed 1, 3, 5, and 7 days after drug administration. Liver triglycerides were quantified, and plasma bilirubin, ALT, AST, and non-esterified fatty acids (NEFA) were measured. The mRNA and protein levels of genes involved in hepatic fatty acid synthesis, β-oxidation, very low-density lipoprotein (VLDL) secretion, and white adipose tissue (WAT) lipolysis were determined. Mice developed hepatic steatosis after PEG-ASNase, which associated with increases in bilirubin, ALT, and AST. The hepatic genes Ppara, Lcad/Mcad, Hadhb, Apob100, and Mttp were upregulated, and Srebp-1c and Fas were downregulated after PEG-ASNase. Increased plasma NEFA, WAT loss, and adipose tissue lipolysis were also observed after PEG-ASNase. Furthermore, we found that PEG-ASNase-induced liver injury was exacerbated in obese and aged mice, consistent with clinical studies of ASNase-induced liver injury. Our data suggest that PEG-ASNase-induced liver injury is due to drug-induced lipolysis and lipid redistribution to the liver.
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Affiliation(s)
- Gundala Venkata Naveen Kumar
- Department of Pharmaceutical Sciences and Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
| | - Keito Hoshitsuki
- Department of Pharmaceutical Sciences and Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
- Division of General Internal Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Sanjay Rathod
- Department of Pharmaceutical Sciences and Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
| | - Manda J. Ramsey
- Department of Pharmaceutical Sciences and Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
| | - Lauren Kokai
- Department of Plastic Surgery, University of Pittsburgh and the McGowan Institute for Regenerative Medicine, Pittsburgh, PA 15261, USA
| | - Erin E. Kershaw
- University of Pittsburgh, Division of Endocrinology, Department of Medicine, Pittsburgh, PA 15261, USA
| | - Wen Xie
- Department of Pharmaceutical Sciences and Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
| | - Christian A. Fernandez
- Department of Pharmaceutical Sciences and Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
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Khan MS, Spann RA, Münzberg H, Yu S, Albaugh VL, He Y, Berthoud HR, Morrison CD. Protein Appetite at the Interface between Nutrient Sensing and Physiological Homeostasis. Nutrients 2021; 13:4103. [PMID: 34836357 PMCID: PMC8620426 DOI: 10.3390/nu13114103] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/04/2021] [Accepted: 11/11/2021] [Indexed: 12/19/2022] Open
Abstract
Feeding behavior is guided by multiple competing physiological needs, as animals must sense their internal nutritional state and then identify and consume foods that meet nutritional needs. Dietary protein intake is necessary to provide essential amino acids and represents a specific, distinct nutritional need. Consistent with this importance, there is a relatively strong body of literature indicating that protein intake is defended, such that animals sense the restriction of protein and adaptively alter feeding behavior to increase protein intake. Here, we argue that this matching of food consumption with physiological need requires at least two concurrent mechanisms: the first being the detection of internal nutritional need (a protein need state) and the second being the discrimination between foods with differing nutritional compositions. In this review, we outline various mechanisms that could mediate the sensing of need state and the discrimination between protein-rich and protein-poor foods. Finally, we briefly describe how the interaction of these mechanisms might allow an animal to self-select between a complex array of foods to meet nutritional needs and adaptively respond to changes in either the external environment or internal physiological state.
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Affiliation(s)
| | | | | | | | | | | | | | - Christopher D. Morrison
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA; (M.S.K.); (R.A.S.); (H.M.); (S.Y.); (V.L.A.); (Y.H.); (H.-R.B.)
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9
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Hepatic Nfe2l2 Is Not an Essential Mediator of the Metabolic Phenotype Produced by Dietary Methionine Restriction. Nutrients 2021; 13:nu13061788. [PMID: 34073838 PMCID: PMC8225036 DOI: 10.3390/nu13061788] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/13/2021] [Accepted: 05/20/2021] [Indexed: 12/15/2022] Open
Abstract
The principal sensing of dietary methionine restriction (MR) occurs in the liver, where it activates multiple transcriptional programs that mediate various biological components of the response. Hepatic Fgf21 is a key target and essential endocrine mediator of the metabolic phenotype produced by dietary MR. The transcription factor, Nfe2l2, is also activated by MR and functions in tandem with hepatic Atf4 to transactivate multiple, antioxidative components of the integrated stress response. However, it is unclear whether the transcriptional responses linked to Nfe2l2 activation by dietary MR are essential to the biological efficacy of the diet. Using mice with liver-specific deletion of Nfe2l2 (Nfe2l2fl/(Alb)) and their floxed littermates (Nfe2l2fl/fl) fed either Control or MR diets, the absence of hepatic Nfe2l2 had no effect on the ability of the MR diet to increase FGF21, reduce body weight and adiposity, and increase energy expenditure. Moreover, the primary elements of the hepatic transcriptome were similarly affected by MR in both genotypes, with the only major differences occurring in induction of the P450-associated drug metabolism pathway and the pentose glucuronate interconversion pathway. The biological significance of these pathways is uncertain but we conclude that hepatic Nfe2l2 is not essential in mediating the metabolic effects of dietary MR.
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10
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Restriction of essential amino acids dictates the systemic metabolic response to dietary protein dilution. Nat Commun 2020; 11:2894. [PMID: 32518324 PMCID: PMC7283339 DOI: 10.1038/s41467-020-16568-z] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 05/12/2020] [Indexed: 02/07/2023] Open
Abstract
Dietary protein dilution (DPD) promotes metabolic-remodelling and -health but the precise nutritional components driving this response remain elusive. Here, by mimicking amino acid (AA) supply from a casein-based diet, we demonstrate that restriction of dietary essential AA (EAA), but not non-EAA, drives the systemic metabolic response to total AA deprivation; independent from dietary carbohydrate supply. Furthermore, systemic deprivation of threonine and tryptophan, independent of total AA supply, are both adequate and necessary to confer the systemic metabolic response to both diet, and genetic AA-transport loss, driven AA restriction. Dietary threonine restriction (DTR) retards the development of obesity-associated metabolic dysfunction. Liver-derived fibroblast growth factor 21 is required for the metabolic remodelling with DTR. Strikingly, hepatocyte-selective establishment of threonine biosynthetic capacity reverses the systemic metabolic response to DTR. Taken together, our studies of mice demonstrate that the restriction of EAA are sufficient and necessary to confer the systemic metabolic effects of DPD. Dietary protein dilution, where protein is reduced and replaced by other nutrient sources without caloric restriction, promotes metabolic health via the hepatokine Fgf21. Here, the authors show that essential amino acids threonine and tryptophan are necessary and sufficient to induce these effects.
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11
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Golonka RM, Xiao X, Abokor AA, Joe B, Vijay-Kumar M. Altered nutrient status reprograms host inflammation and metabolic health via gut microbiota. J Nutr Biochem 2020; 80:108360. [PMID: 32163821 PMCID: PMC7242157 DOI: 10.1016/j.jnutbio.2020.108360] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/07/2020] [Accepted: 02/08/2020] [Indexed: 02/07/2023]
Abstract
The metabolism of macro- and micronutrients is a complex and highly regulated biological process. An imbalance in the metabolites and their signaling networks can lead to nonresolving inflammation and consequently to the development of chronic inflammatory-associated diseases. Therefore, identifying the accumulated metabolites and altered pathways during inflammatory disorders would not only serve as "real-time" markers but also help in the development of nutritional therapeutics. In this review, we explore recent research that has delved into elucidating the effects of carbohydrate/calorie restriction, protein malnutrition, lipid emulsions and micronutrient deficiencies on metabolic health and inflammation. Moreover, we describe the integrated stress response in terms of amino acid starvation and lipemia and how this modulates new age diseases such as inflammatory bowel disease and atherosclerosis. Lastly, we explain the latest research on metaflammation and inflammaging. This review focuses on multiple signaling pathways, including, but not limited to, the FGF21-β-hydroxybutryate-NLRP3 axis, the GCN2-eIF2α-ATF4 pathway, the von Hippel-Lindau/hypoxia-inducible transcription factor pathway and the TMAO-PERK-FoxO1 axis. Additionally, throughout the review, we explain how the gut microbiota responds to altered nutrient status and also how antimicrobial peptides generated from nutrient-based signaling pathways can modulate the gut microbiota. Collectively, it must be emphasized that metabolic starvation and inflammation are strongly regulated by both environmental (i.e., nutrition, gut microbiome) and nonenvironmental (i.e., genetics) factors, which can influence the susceptibility to inflammatory disorders.
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Affiliation(s)
- Rachel M Golonka
- UT Microbiome Consortium, Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
| | - Xia Xiao
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Ahmed A Abokor
- UT Microbiome Consortium, Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
| | - Bina Joe
- UT Microbiome Consortium, Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
| | - Matam Vijay-Kumar
- UT Microbiome Consortium, Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614.
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12
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Hill CM, Qualls-Creekmore E, Berthoud HR, Soto P, Yu S, McDougal DH, Münzberg H, Morrison CD. FGF21 and the Physiological Regulation of Macronutrient Preference. Endocrinology 2020; 161:5734531. [PMID: 32047920 PMCID: PMC7053867 DOI: 10.1210/endocr/bqaa019] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 02/06/2020] [Indexed: 12/15/2022]
Abstract
The ability to respond to variations in nutritional status depends on regulatory systems that monitor nutrient intake and adaptively alter metabolism and feeding behavior during nutrient restriction. There is ample evidence that the restriction of water, sodium, or energy intake triggers adaptive responses that conserve existing nutrient stores and promote the ingestion of the missing nutrient, and that these homeostatic responses are mediated, at least in part, by nutritionally regulated hormones acting within the brain. This review highlights recent research that suggests that the metabolic hormone fibroblast growth factor 21 (FGF21) acts on the brain to homeostatically alter macronutrient preference. Circulating FGF21 levels are robustly increased by diets that are high in carbohydrate but low in protein, and exogenous FGF21 treatment reduces the consumption of sweet foods and alcohol while alternatively increasing the consumption of protein. In addition, while control mice adaptively shift macronutrient preference and increase protein intake in response to dietary protein restriction, mice that lack either FGF21 or FGF21 signaling in the brain fail to exhibit this homeostatic response. FGF21 therefore mediates a unique physiological niche, coordinating adaptive shifts in macronutrient preference that serve to maintain protein intake in the face of dietary protein restriction.
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Affiliation(s)
| | | | | | - Paul Soto
- Pennington Biomedical Research Center, Baton Rouge, LA
| | - Sangho Yu
- Pennington Biomedical Research Center, Baton Rouge, LA
| | | | | | - Christopher D Morrison
- Pennington Biomedical Research Center, Baton Rouge, LA
- Correspondence: Christopher D. Morrison, Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA, 70808. E-mail:
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13
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Fibroblast Growth Factor 21 and the Adaptive Response to Nutritional Challenges. Int J Mol Sci 2019; 20:ijms20194692. [PMID: 31546675 PMCID: PMC6801670 DOI: 10.3390/ijms20194692] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 02/07/2023] Open
Abstract
The Fibroblast Growth Factor 21 (FGF21) is considered an attractive therapeutic target for obesity and obesity-related disorders due to its beneficial effects in lipid and carbohydrate metabolism. FGF21 response is essential under stressful conditions and its metabolic effects depend on the inducer factor or stress condition. FGF21 seems to be the key signal which communicates and coordinates the metabolic response to reverse different nutritional stresses and restores the metabolic homeostasis. This review is focused on describing individually the FGF21-dependent metabolic response activated by some of the most common nutritional challenges, the signal pathways triggering this response, and the impact of this response on global homeostasis. We consider that this is essential knowledge to identify the potential role of FGF21 in the onset and progression of some of the most prevalent metabolic pathologies and to understand the potential of FGF21 as a target for these diseases. After this review, we conclude that more research is needed to understand the mechanisms underlying the role of FGF21 in macronutrient preference and food intake behavior, but also in β-klotho regulation and the activity of the fibroblast activation protein (FAP) to uncover its therapeutic potential as a way to increase the FGF21 signaling.
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14
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Nikonorova IA, Zhu Q, Signore CC, Mirek ET, Jonsson WO, Kong B, Guo GL, Belden WJ, Anthony TG. Age modulates liver responses to asparaginase-induced amino acid stress in mice. J Biol Chem 2019; 294:13864-13875. [PMID: 31413113 DOI: 10.1074/jbc.ra119.009864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/06/2019] [Indexed: 11/06/2022] Open
Abstract
Asparaginase is an amino acid-depleting agent used to treat blood cancers. Metabolic complications due to asparaginase affect liver function in humans. To examine how the liver response to asparaginase changes during maturity to adulthood, here we treated juvenile (2-week), young adult (8-week), and mature adult (16-week) mice with drug or excipient for 1 week and conducted RNA-Seq and functional analyses. Asparaginase reduced body growth and liver mass in juveniles but not in the adult animals. Unbiased exploration of the effect of asparaginase on the liver transcriptome revealed that the integrated stress response (ISR) was the only molecular signature shared across the ages, corroborating similar eukaryotic initiation factor 2 phosphorylation responses to asparaginase at all ages. Juvenile livers exhibited steatosis and iron accumulation following asparaginase exposure along with a hepatic gene signature indicating that asparaginase uniquely affects lipid, cholesterol, and iron metabolism in juvenile mice. In contrast, asparaginase-treated adult mice displayed greater variability in liver function, which correlated with an acute-phase inflammatory response gene signature. Asparaginase-exposed adults also had a serine/glycine/one-carbon metabolism gene signature in liver that corresponded with reduced circulating glycine and serine levels. These results establish the ISR as a conserved response to asparaginase-mediated amino acid deprivation and provide new insights into the relationship between the liver transcriptome and hepatic function upon asparaginase exposure.
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Affiliation(s)
- Inna A Nikonorova
- Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - Qiaoqiao Zhu
- Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - Christina C Signore
- Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - Emily T Mirek
- Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - Bo Kong
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, New Jersey 08854
| | - Grace L Guo
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, New Jersey 08854
| | - William J Belden
- Department of Animal Sciences, Rutgers University, New Brunswick, New Jersey 08901
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey 08901
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15
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Jonsson WO, Margolies NS, Anthony TG. Dietary Sulfur Amino Acid Restriction and the Integrated Stress Response: Mechanistic Insights. Nutrients 2019; 11:nu11061349. [PMID: 31208042 PMCID: PMC6627990 DOI: 10.3390/nu11061349] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/07/2019] [Accepted: 06/11/2019] [Indexed: 12/17/2022] Open
Abstract
Dietary sulfur amino acid restriction, also referred to as methionine restriction, increases food intake and energy expenditure and alters body composition in rodents, resulting in improved metabolic health and a longer lifespan. Among the known nutrient-responsive signaling pathways, the evolutionary conserved integrated stress response (ISR) is a lesser-understood candidate in mediating the hormetic effects of dietary sulfur amino acid restriction (SAAR). A key feature of the ISR is the concept that a family of protein kinases phosphorylates eukaryotic initiation factor 2 (eIF2), dampening general protein synthesis to conserve cellular resources. This slowed translation simultaneously allows for preferential translation of genes with special sequence features in the 5' leader. Among this class of mRNAs is activating transcription factor 4 (ATF4), an orchestrator of transcriptional control during nutrient stress. Several ATF4 gene targets help execute key processes affected by SAAR such as lipid metabolism, the transsulfuration pathway, and antioxidant defenses. Exploration of the canonical ISR demonstrates that eIF2 phosphorylation is not necessary for ATF4-driven changes in the transcriptome during SAAR. Additional research is needed to clarify the regulation of ATF4 and its gene targets during SAAR.
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Affiliation(s)
- William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
| | - Nicholas S Margolies
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
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16
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Buffalo liver transcriptome analysis suggests immune tolerance as its key adaptive mechanism during early postpartum negative energy balance. Funct Integr Genomics 2019; 19:759-773. [DOI: 10.1007/s10142-019-00676-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 03/03/2019] [Accepted: 04/01/2019] [Indexed: 01/25/2023]
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17
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Parzych K, Saavedra-García P, Valbuena GN, Al-Sadah HA, Robinson ME, Penfold L, Kuzeva DM, Ruiz-Tellez A, Loaiza S, Holzmann V, Caputo V, Johnson DC, Kaiser MF, Karadimitris A, Lam EWF, Chevet E, Feldhahn N, Keun HC, Auner HW. The coordinated action of VCP/p97 and GCN2 regulates cancer cell metabolism and proteostasis during nutrient limitation. Oncogene 2019; 38:3216-3231. [PMID: 30626938 PMCID: PMC6756015 DOI: 10.1038/s41388-018-0651-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 12/30/2022]
Abstract
VCP/p97 regulates numerous cellular functions by mediating protein degradation through its segregase activity. Its key role in governing protein homoeostasis has made VCP/p97 an appealing anticancer drug target. Here, we provide evidence that VCP/p97 acts as a regulator of cellular metabolism. We found that VCP/p97 was tied to multiple metabolic processes on the gene expression level in a diverse range of cancer cell lines and in patient-derived multiple myeloma cells. Cellular VCP/p97 dependency to maintain proteostasis was increased under conditions of glucose and glutamine limitation in a range of cancer cell lines from different tissues. Moreover, glutamine depletion led to increased VCP/p97 expression, whereas VCP/p97 inhibition perturbed metabolic processes and intracellular amino acid turnover. GCN2, an amino acid-sensing kinase, attenuated stress signalling and cell death triggered by VCP/p97 inhibition and nutrient shortages and modulated ERK activation, autophagy, and glycolytic metabolite turnover. Together, our data point to an interconnected role of VCP/p97 and GCN2 in maintaining cancer cell metabolic and protein homoeostasis.
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Affiliation(s)
- Katarzyna Parzych
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Paula Saavedra-García
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Gabriel N Valbuena
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital, London, UK
| | - Hibah A Al-Sadah
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Mark E Robinson
- Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Lucy Penfold
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Desislava M Kuzeva
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Angie Ruiz-Tellez
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Sandra Loaiza
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Viktoria Holzmann
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Valentina Caputo
- Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - David C Johnson
- Division of Molecular Pathfology, Institute of Cancer Research, Sutton, UK
| | - Martin F Kaiser
- Division of Molecular Pathfology, Institute of Cancer Research, Sutton, UK
| | | | - Eric W-F Lam
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital, London, UK
| | - Eric Chevet
- INSERM U1242, Chemistry, Oncogenesis, Stress, Signaling, Université de Rennes 1, Rennes, France
- Centre de Lutte Contre le Cancer Eugène Marquis Rennes, Rennes, France
| | - Niklas Feldhahn
- Centre for Haematology, Department of Medicine, Imperial College London, London, UK
| | - Hector C Keun
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital, London, UK
| | - Holger W Auner
- Cancer Cell Protein Metabolism Group, Centre for Haematology, Department of Medicine, Imperial College London, London, UK.
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18
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Amino acid transporters in the regulation of insulin secretion and signalling. Biochem Soc Trans 2019; 47:571-590. [PMID: 30936244 DOI: 10.1042/bst20180250] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/24/2019] [Accepted: 02/25/2019] [Indexed: 01/02/2023]
Abstract
Amino acids are increasingly recognised as modulators of nutrient disposal, including their role in regulating blood glucose through interactions with insulin signalling. More recently, cellular membrane transporters of amino acids have been shown to form a pivotal part of this regulation as they are primarily responsible for controlling cellular and circulating amino acid concentrations. The availability of amino acids regulated by transporters can amplify insulin secretion and modulate insulin signalling in various tissues. In addition, insulin itself can regulate the expression of numerous amino acid transporters. This review focuses on amino acid transporters linked to the regulation of insulin secretion and signalling with a focus on those of the small intestine, pancreatic β-islet cells and insulin-responsive tissues, liver and skeletal muscle. We summarise the role of the amino acid transporter B0AT1 (SLC6A19) and peptide transporter PEPT1 (SLC15A1) in the modulation of global insulin signalling via the liver-secreted hormone fibroblast growth factor 21 (FGF21). The role of vesicular vGLUT (SLC17) and mitochondrial SLC25 transporters in providing glutamate for the potentiation of insulin secretion is covered. We also survey the roles SNAT (SLC38) family and LAT1 (SLC7A5) amino acid transporters play in the regulation of and by insulin in numerous affective tissues. We hypothesise the small intestine amino acid transporter B0AT1 represents a crucial nexus between insulin, FGF21 and incretin hormone signalling pathways. The aim is to give an integrated overview of the important role amino acid transporters have been found to play in insulin-regulated nutrient signalling.
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19
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Feng W, Lei T, Wang Y, Feng R, Yuan J, Shen X, Wu Y, Gao J, Ding W, Lu Z. GCN2 deficiency ameliorates cardiac dysfunction in diabetic mice by reducing lipotoxicity and oxidative stress. Free Radic Biol Med 2019; 130:128-139. [PMID: 30389499 DOI: 10.1016/j.freeradbiomed.2018.10.445] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 10/19/2018] [Accepted: 10/27/2018] [Indexed: 12/18/2022]
Abstract
Excessive myocardial lipid accumulation is a major feature of diabetic cardiomyopathy (DCM). Although general control nonderepressible 2 (GCN2) has been identified as a sensor of amino acid availability, it also functions as an important regulator of hepatic lipid metabolism. Our previous studies have reported that GCN2 promotes pressure overload or doxorubicin-induced cardiac dysfunction by increasing cardiomyocyte apoptosis and myocardial oxidative stress. However, the impact of GCN2 on the development of DCM remains unclear. In this study, we investigated the effect of GCN2 on DCM in type 1 and type 2 diabetes animal models. After streptozotocin (STZ) or high-fat diet (HFD) plus low-dose STZ treatments, GCN2-/- mice developed less cardiac dysfunction, hyperlipidemia, myocardial hypertrophy, fibrosis, lipid accumulation, oxidative stress, inflammation and apoptosis compared with wild-type (WT) mice. In diabetic hearts, GCN2 deficiency attenuated the upregulation of peroxisome proliferator-activated receptor alpha (PPARα) and gamma (PPARγ), the phosphorylation of eIF2α and the induction of activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP), as well as the reduction of Bcl-2. Furthermore, we found that knockdown of GCN2 attenuated, whereas overexpression of GCN2 exacerbated, high glucose or palmitic acid-induced cell death, oxidative and endoplasmic reticulum stress and lipid accumulation in H9C2 cells. Collectively, our data provide evidence that GCN2 deficiency protects cardiac function by reducing lipid accumulation, oxidative stress and cell death. Our findings suggest that strategies to inhibit GCN2 activity in the heart may be novel approaches for DCM therapy.
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Affiliation(s)
- Wei Feng
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tong Lei
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yue Wang
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Run Feng
- Beijing Laboratory Animal Research Center, Beijing 100012, China
| | - Juntao Yuan
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiyue Shen
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yongguang Wu
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junling Gao
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjun Ding
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Zhongbing Lu
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China.
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20
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Hill CM, Berthoud HR, Münzberg H, Morrison CD. Homeostatic sensing of dietary protein restriction: A case for FGF21. Front Neuroendocrinol 2018; 51:125-131. [PMID: 29890191 PMCID: PMC6175661 DOI: 10.1016/j.yfrne.2018.06.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/03/2018] [Accepted: 06/07/2018] [Indexed: 12/31/2022]
Abstract
Restriction of dietary protein intake increases food intake and energy expenditure, reduces growth, and alters amino acid, lipid, and glucose metabolism. While these responses suggest that animals 'sense' variations in amino acid consumption, the basic physiological mechanism mediating the adaptive response to protein restriction has been largely undescribed. In this review we make the case that the liver-derived metabolic hormone FGF21 is the key signal which communicates and coordinates the homeostatic response to dietary protein restriction. Support for this model centers on the evidence that FGF21 is induced by the restriction of dietary protein or amino acid intake and is required for adaptive changes in metabolism and behavior. FGF21 occupies a unique endocrine niche, being induced when energy intake is adequate but protein and carbohydrate are imbalanced. Collectively, the evidence thus suggests that FGF21 is the first known endocrine signal of dietary protein restriction.
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Affiliation(s)
- Cristal M Hill
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, United States
| | | | - Heike Münzberg
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, United States
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21
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Liu S, Yuan J, Yue W, Bi Y, Shen X, Gao J, Xu X, Lu Z. GCN2 deficiency protects against high fat diet induced hepatic steatosis and insulin resistance in mice. Biochim Biophys Acta Mol Basis Dis 2018; 1864:3257-3267. [PMID: 30006154 DOI: 10.1016/j.bbadis.2018.07.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 06/27/2018] [Accepted: 07/09/2018] [Indexed: 02/05/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic lipid deposition and oxidative stress. It has been demonstrated that general control nonderepressible 2 (GCN2) is required to maintain hepatic fatty acid homeostasis under conditions of amino acid deprivation. However, the impact of GCN2 on the development of NAFLD has not been investigated. In this study, we used Gcn2-/- mice to investigate the effect of GCN2 on high fat diet (HFD)-induced hepatic steatosis. After HFD feeding for 12 weeks, Gcn2-/- mice were less obese than wild-type (WT) mice, and Gcn2-/- significantly attenuated HFD-induced liver dysfunction, hepatic steatosis and insulin resistance. In the livers of the HFD-fed mice, GCN2 deficiency resulted in higher levels of lipolysis genes, lower expression of genes related to FA synthesis, transport and lipogenesis, and less induction of oxidative stress. Furthermore, we found that knockdown of GCN2 attenuated, whereas overexpression of GCN2 exacerbated, palmitic acid-induced steatosis, oxidative & ER stress, and changes of peroxisome proliferator-activated receptor gamma (PPARγ), fatty acid synthase (FAS) and metallothionein (MT) expression in HepG2 cells. Collectively, our data provide evidences that GCN2 deficiency protects against HFD-induced hepatic steatosis by inhibiting lipogenesis and reducing oxidative stress. Our findings suggest that strategies to inhibit GCN2 activity in the liver may provide a novel approach to attenuate NAFLD development.
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Affiliation(s)
- Shasha Liu
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Juntao Yuan
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenhui Yue
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China; Department of Cardiology, Pan-Vascular Research Institute, Shanghai Tenth People's Hospital, Tongji University, Shanghai 200072, China
| | - Yanwei Bi
- Shantou University Medical College, Shantou 515041, China
| | - Xiyue Shen
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junling Gao
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Xu
- Department of Exercise Rehabilitation, Shanghai University of Sport, Shanghai 200438, China.
| | - Zhongbing Lu
- College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China.
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22
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BonDurant LD, Potthoff MJ. Fibroblast Growth Factor 21: A Versatile Regulator of Metabolic Homeostasis. Annu Rev Nutr 2018; 38:173-196. [PMID: 29727594 DOI: 10.1146/annurev-nutr-071816-064800] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fibroblast growth factor 21 (FGF21) is an endocrine hormone derived from the liver that exerts pleiotropic effects on the body to maintain overall metabolic homeostasis. During the past decade, there has been an enormous effort made to understand the physiological roles of FGF21 in regulating metabolism and to identify the mechanism for its potent pharmacological effects to reverse diabetes and obesity. Through both human and rodent studies, it is now evident that FGF21 levels are dynamically regulated by nutrient sensing, and consequently FGF21 functions as a critical regulator of nutrient homeostasis. In addition, recent studies using new genetic and molecular tools have provided critical insight into the actions of this endocrine factor. This review examines the numerous functions of FGF21 and highlights the therapeutic potential of FGF21-targeted pathways for treating metabolic disease.
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Affiliation(s)
- Lucas D BonDurant
- Department of Pharmacology and Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA;
| | - Matthew J Potthoff
- Department of Pharmacology and Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA;
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23
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Ramos-Lopez O, Riezu-Boj JI, Milagro FI, Martinez JA. DNA methylation signatures at endoplasmic reticulum stress genes are associated with adiposity and insulin resistance. Mol Genet Metab 2018; 123:50-58. [PMID: 29221916 DOI: 10.1016/j.ymgme.2017.11.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/27/2017] [Accepted: 11/27/2017] [Indexed: 12/26/2022]
Abstract
A sustained activation of the unfolded protein response and the subsequent endoplasmic reticulum (ER) stress has been involved in the onset and severity of several metabolic diseases. The aim of this study was to analyze the association of DNA methylation signatures at ER stress genes with adiposity traits and related metabolic disorders. An epigenomic analysis within the Methyl Epigenome Network Association (MENA) project was conducted in an adult population (n=474). DNA methylation status in peripheral white blood cells was analyzed by a microarray approach. KEGG database was used to the characterization and discrimination of genes involved in the "protein processing in endoplasmic reticulum pathway". Anthropometric measurements and plasma metabolic profiles were analyzed. A total of 15 CpG sites at genes participating in ER pathway were strongly correlated with BMI after adjusted linear regression analyses (p<0.0001). These included cg08188400 (MAP2K7), cg20541779 (CASP12), cg24776411 (EIF2AK1), cg14190817 (HSPA5), cg21376454 (ERN1), cg06666486 (EIF2AK1), cg03211481 (DNAJC1), cg18357645 (OS9), cg05801879 (MBTPS1), cg20964082 (ERO1LB), cg17300868 (NFE2L2), cg03384128 (EIF2AK4), cg02712587 (EIF2AK4), cg04972384 (SELS), cg02240686 (EIF2AK2). Noteworthy, most of them were implicated in ER stress (p=2.9E-09). However, only methylation levels at cg20964082 (ERO1LB), cg17300868 (NFE2L2), cg05801879 (MBTPS1), and cg03384128 (EIF2AK4) also correlated with total fat mass. Interestingly, significant associations between methylation patterns at cg20964082 (ERO1LB) and cg17300868 (NFE2L2) and insulin and HOMA-IR index were found, whereas cg05801879 (MBTPS1) and cg03384128 (EIF2AK4) were correlated with triglyceride levels. This study suggests associations of methylation signatures at ER stress genes with adiposity and insulin resistance, as revealed by discriminative pathway analyses.
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Affiliation(s)
- Omar Ramos-Lopez
- Department of Nutrition, Food Science and Physiology, Center for Nutrition Research, University of Navarra, Pamplona, Spain
| | - Jose I Riezu-Boj
- Department of Nutrition, Food Science and Physiology, Center for Nutrition Research, University of Navarra, Pamplona, Spain; Navarra Institute for Health Research (IdiSNA), Pamplona, Spain
| | - Fermin I Milagro
- Department of Nutrition, Food Science and Physiology, Center for Nutrition Research, University of Navarra, Pamplona, Spain; Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Carlos III Institute, Madrid, Spain
| | - J Alfredo Martinez
- Department of Nutrition, Food Science and Physiology, Center for Nutrition Research, University of Navarra, Pamplona, Spain; Navarra Institute for Health Research (IdiSNA), Pamplona, Spain; Biomedical Research Centre Network in Physiopathology of Obesity and Nutrition (CIBERobn), Carlos III Institute, Madrid, Spain; Madrid Institute of Advanced Studies (IMDEA Food), Madrid, Spain.
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24
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Latimer MN, Freij KW, Cleveland BM, Biga PR. Physiological and Molecular Mechanisms of Methionine Restriction. Front Endocrinol (Lausanne) 2018; 9:217. [PMID: 29780356 PMCID: PMC5945823 DOI: 10.3389/fendo.2018.00217] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 04/17/2018] [Indexed: 01/17/2023] Open
Abstract
Methionine restriction (MR) has been studied extensively over the last 25 years for its role in altering metabolic hallmarks of disease. Animals subjected to MR, display changes in metabolic flexibility demonstrated by increases in energy expenditure, glucose tolerance, and lifespan. These changes have been well characterized in a number of model systems and significant progress has been made in understanding how hepatic fibroblast growth factor 21 links MR to several components of its metabolic phenotype. Despite these advances, a complete understanding of mechanisms engaged by dietary MR remains elusive. In this review, we offer a brief history of MR and its known mechanisms associated with stress, metabolism, and lifespan extension. We consider the role of epigenetics in the response of animals to MR and propose a novel epigenetic pathway involving the regulation of microRNAs during MR.
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Affiliation(s)
- Mary Neslund Latimer
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Khalid Walid Freij
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Beth M. Cleveland
- National Center for Cool and Cold Water Aquaculture, Agricultural Research Service (USDA), Kearneysville, WV, United States
| | - Peggy R. Biga
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, United States
- *Correspondence: Peggy R. Biga,
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25
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Cummings NE, Williams EM, Kasza I, Konon EN, Schaid MD, Schmidt BA, Poudel C, Sherman DS, Yu D, Arriola Apelo SI, Cottrell SE, Geiger G, Barnes ME, Wisinski JA, Fenske RJ, Matkowskyj KA, Kimple ME, Alexander CM, Merrins MJ, Lamming DW. Restoration of metabolic health by decreased consumption of branched-chain amino acids. J Physiol 2017; 596:623-645. [PMID: 29266268 DOI: 10.1113/jp275075] [Citation(s) in RCA: 222] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 11/20/2017] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS We recently found that feeding healthy mice a diet with reduced levels of branched-chain amino acids (BCAAs), which are associated with insulin resistance in both humans and rodents, modestly improves glucose tolerance and slows fat mass gain. In the present study, we show that a reduced BCAA diet promotes rapid fat mass loss without calorie restriction in obese mice. Selective reduction of dietary BCAAs also restores glucose tolerance and insulin sensitivity to obese mice, even as they continue to consume a high-fat, high-sugar diet. A low BCAA diet transiently induces FGF21 (fibroblast growth factor 21) and increases energy expenditure. We suggest that dietary protein quality (i.e. the precise macronutrient composition of dietary protein) may impact the effectiveness of weight loss diets. ABSTRACT Obesity and diabetes are increasing problems around the world, and although even moderate weight loss can improve metabolic health, reduced calorie diets are notoriously difficult to sustain. Branched-chain amino acids (BCAAs; leucine, isoleucine and valine) are elevated in the blood of obese, insulin-resistant humans and rodents. We recently demonstrated that specifically reducing dietary levels of BCAAs has beneficial effects on the metabolic health of young, growing mice, improving glucose tolerance and modestly slowing fat mass gain. In the present study, we examine the hypothesis that reducing dietary BCAAs will promote weight loss, reduce adiposity, and improve blood glucose control in diet-induced obese mice with pre-existing metabolic syndrome. We find that specifically reducing dietary BCAAs rapidly reverses diet-induced obesity and improves glucoregulatory control in diet-induced obese mice. Most dramatically, mice eating an otherwise unhealthy high-calorie, high-sugar Western diet with reduced levels of BCAAs lost weight and fat mass rapidly until regaining a normal weight. Importantly, this normalization of weight was mediated not by caloric restriction or increased activity, but by increased energy expenditure, and was accompanied by a transient induction of the energy balance regulating hormone FGF21 (fibroblast growth factor 21). Consumption of a Western diet reduced in BCAAs was also accompanied by a dramatic improvement in glucose tolerance and insulin resistance. Our results link dietary BCAAs with the regulation of metabolic health and energy balance in obese animals, and suggest that specifically reducing dietary BCAAs may represent a highly translatable option for the treatment of obesity and insulin resistance.
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Affiliation(s)
- Nicole E Cummings
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Elizabeth M Williams
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Ildiko Kasza
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI, USA
| | - Elizabeth N Konon
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Michael D Schaid
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Interdisciplinary Graduate Program in Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Brian A Schmidt
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Chetan Poudel
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Dawn S Sherman
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Deyang Yu
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Molecular and Environmental Toxicology Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Sebastian I Arriola Apelo
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Department of Dairy Science, University of Wisconsin-Madison, Madison, WI, USA
| | - Sara E Cottrell
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Rural and Urban Scholars in Community Health Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Gabriella Geiger
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Macy E Barnes
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Jaclyn A Wisinski
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
| | - Rachel J Fenske
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Interdisciplinary Graduate Program in Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Kristina A Matkowskyj
- William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,University of Wisconsin Carbone Cancer Center, Madison, WI, USA.,Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Michelle E Kimple
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA.,Interdisciplinary Graduate Program in Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA.,Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI, USA
| | - Caroline M Alexander
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI, USA
| | - Matthew J Merrins
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Dudley W Lamming
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,William S. Middleton Memorial Veterans Hospital, Madison, WI, USA.,Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA.,Interdisciplinary Graduate Program in Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA.,Molecular and Environmental Toxicology Program, University of Wisconsin-Madison, Madison, WI, USA.,University of Wisconsin Carbone Cancer Center, Madison, WI, USA
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26
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Pettit AP, Jonsson WO, Bargoud AR, Mirek ET, Peelor FF, Wang Y, Gettys TW, Kimball SR, Miller BF, Hamilton KL, Wek RC, Anthony TG. Dietary Methionine Restriction Regulates Liver Protein Synthesis and Gene Expression Independently of Eukaryotic Initiation Factor 2 Phosphorylation in Mice. J Nutr 2017; 147:1031-1040. [PMID: 28446632 PMCID: PMC5443467 DOI: 10.3945/jn.116.246710] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/20/2017] [Accepted: 03/15/2017] [Indexed: 01/12/2023] Open
Abstract
Background: The phosphorylation of eukaryotic initiation factor 2 (p-eIF2) during dietary amino acid insufficiency reduces protein synthesis and alters gene expression via the integrated stress response (ISR).Objective: We explored whether a Met-restricted (MR) diet activates the ISR to reduce body fat and regulate protein balance.Methods: Male and female mice aged 3-6 mo with either whole-body deletion of general control nonderepressible 2 (Gcn2) or liver-specific deletion of protein kinase R-like endoplasmic reticulum kinase (Perk) alongside wild-type or floxed control mice were fed an obesogenic diet sufficient in Met (0.86%) or an MR (0.12% Met) diet for ≤5 wk. Ala enrichment with deuterium was measured to calculate protein synthesis rates. The guanine nucleotide exchange factor activity of eIF2B was measured alongside p-eIF2 and hepatic mRNA expression levels at 2 d and 5 wk. Metabolic phenotyping was conducted at 4 wk, and body composition was measured throughout. Results were evaluated with the use of ANOVA (P < 0.05).Results: Feeding an MR diet for 2 d did not increase hepatic p-eIF2 or reduce eIF2B activity in wild-type or Gcn2-/- mice, yet many genes transcriptionally regulated by the ISR were altered in both strains in the same direction and amplitude. Feeding an MR diet for 5 wk increased p-eIF2 and reduced eIF2B activity in wild-type but not Gcn2-/- mice, yet ISR-regulated genes altered in both strains similarly. Furthermore, the MR diet reduced mixed and cytosolic but not mitochondrial protein synthesis in both the liver and skeletal muscle regardless of Gcn2 status. Despite the similarities between strains, the MR diet did not increase energy expenditure or reduce body fat in Gcn2-/- mice. Finally, feeding the MR diet to mice with Perk deleted in the liver increased hepatic p-eIF2 and altered body composition similar to floxed controls.Conclusions: Hepatic activation of the ISR resulting from an MR diet does not require p-eIF2. Gcn2 status influences body fat loss but not protein balance when Met is restricted.
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Affiliation(s)
- Ashley P Pettit
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Albert R Bargoud
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Emily T Mirek
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Frederick F Peelor
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Yongping Wang
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Thomas W Gettys
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Scot R Kimball
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey PA; and
| | - Benjamin F Miller
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Ronald C Wek
- Department of Biochemistry of Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ;
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27
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Al-Baghdadi RJT, Nikonorova IA, Mirek ET, Wang Y, Park J, Belden WJ, Wek RC, Anthony TG. Role of activating transcription factor 4 in the hepatic response to amino acid depletion by asparaginase. Sci Rep 2017; 7:1272. [PMID: 28455513 PMCID: PMC5430736 DOI: 10.1038/s41598-017-01041-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/17/2017] [Indexed: 12/18/2022] Open
Abstract
The anti-leukemic agent asparaginase activates the integrated stress response (ISR) kinase GCN2 and inhibits signaling via mechanistic target of rapamycin complex 1 (mTORC1). The study objective was to investigate the protective role of activating transcription factor 4 (ATF4) in controlling the hepatic transcriptome and mediating GCN2-mTORC1 signaling during asparaginase. We compared global gene expression patterns in livers from wildtype, Gcn2−/−, and Atf4−/− mice treated with asparaginase or excipient and further explored selected responses in livers from Atf4+/− mice. Here, we show that ATF4 controls a hepatic gene expression profile that overlaps with GCN2 but is not required for downregulation of mTORC1 during asparaginase. Ingenuity pathway analysis indicates GCN2 independently influences inflammation-mediated hepatic processes whereas ATF4 uniquely associates with cholesterol metabolism and endoplasmic reticulum (ER) stress. Livers from Atf4−/− or Atf4+/− mice displayed an amplification of the amino acid response and ER stress response transcriptional signatures. In contrast, reduction in hepatic mTORC1 signaling was retained in Atf4−/− mice treated with asparaginase. Conclusions: GCN2 and ATF4 serve complementary roles in the hepatic response to asparaginase. GCN2 functions to limit inflammation and mTORC1 signaling whereas ATF4 serves to limit the amino acid response and prevent ER stress during amino acid depletion by asparaginase.
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Affiliation(s)
- Rana J T Al-Baghdadi
- Endocrinology and Animal Biosciences Graduate Program, Rutgers, The State University of New Jersey, New Brunswick, NJ, 0890, USA.,Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Al-Qadisiyah, Al-Qadisiayah, Iraq
| | - Inna A Nikonorova
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Emily T Mirek
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Yongping Wang
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Jinhee Park
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, 0890, USA
| | - William J Belden
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, 0890, USA
| | - Ronald C Wek
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Tracy G Anthony
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers, The State University of New Jersey, New Brunswick, NJ, 08901, USA.
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28
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Nikonorova IA, Al-Baghdadi RJT, Mirek ET, Wang Y, Goudie MP, Wetstein BB, Dixon JL, Hine C, Mitchell JR, Adams CM, Wek RC, Anthony TG. Obesity challenges the hepatoprotective function of the integrated stress response to asparaginase exposure in mice. J Biol Chem 2017; 292:6786-6798. [PMID: 28242759 DOI: 10.1074/jbc.m116.768408] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 02/17/2017] [Indexed: 01/12/2023] Open
Abstract
Obesity increases risk for liver toxicity by the anti-leukemic agent asparaginase, but the mechanism is unknown. Asparaginase activates the integrated stress response (ISR) via sensing amino acid depletion by the eukaryotic initiation factor 2 (eIF2) kinase GCN2. The goal of this work was to discern the impact of obesity, alone versus alongside genetic disruption of the ISR, on mechanisms of liver protection during chronic asparaginase exposure in mice. Following diet-induced obesity, biochemical analysis of livers revealed that asparaginase provoked hepatic steatosis that coincided with activation of another eIF2 kinase PKR-like endoplasmic reticulum kinase (PERK), a major ISR transducer to ER stress. Genetic loss of Gcn2 intensified hepatic PERK activation to asparaginase, yet surprisingly, mRNA levels of key ISR gene targets such as Atf5 and Trib3 failed to increase. Instead, mechanistic target of rapamycin complex 1 (mTORC1) signal transduction was unleashed, and this coincided with liver dysfunction reflected by a failure to maintain hydrogen sulfide production or apolipoprotein B100 (ApoB100) expression. In contrast, obese mice lacking hepatic activating transcription factor 4 (Atf4) showed an exaggerated ISR and greater loss of endogenous hydrogen sulfide but normal inhibition of mTORC1 and maintenance of ApoB100 during asparaginase exposure. In both genetic mouse models, expression and phosphorylation of Sestrin2, an ATF4 gene target, was increased by asparaginase, suggesting mTORC1 inhibition during asparaginase exposure is not driven via eIF2-ATF4-Sestrin2. In conclusion, obesity promotes a maladaptive ISR during asparaginase exposure. GCN2 functions to repress mTORC1 activity and maintain ApoB100 protein levels independently of Atf4 expression, whereas hydrogen sulfide production is promoted via GCN2-ATF4 pathway.
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Affiliation(s)
| | - Rana J T Al-Baghdadi
- the Endocrinology and Animal Biosciences Graduate Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901
| | | | | | | | | | - Joseph L Dixon
- From the Department of Nutritional Sciences, and.,the Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition and Health, New Brunswick, New Jersey 08901
| | - Christopher Hine
- the Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115
| | - James R Mitchell
- the Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115
| | - Christopher M Adams
- the Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, and
| | - Ronald C Wek
- the Department of Biochemistry and Molecular Biology, Indiana University, School of Medicine, Indianapolis, Indiana 46202
| | - Tracy G Anthony
- From the Department of Nutritional Sciences, and .,the Endocrinology and Animal Biosciences Graduate Program, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901.,the Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition and Health, New Brunswick, New Jersey 08901
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29
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Pérez-Martí A, Sandoval V, Marrero PF, Haro D, Relat J. Nutritional regulation of fibroblast growth factor 21: from macronutrients to bioactive dietary compounds. Horm Mol Biol Clin Investig 2016; 30:/j/hmbci.ahead-of-print/hmbci-2016-0034/hmbci-2016-0034.xml. [PMID: 27583468 DOI: 10.1515/hmbci-2016-0034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 07/21/2016] [Indexed: 12/15/2022]
Abstract
Obesity is a worldwide health problem mainly due to its associated comorbidities. Fibroblast growth factor 21 (FGF21) is a peptide hormone involved in metabolic homeostasis in healthy individuals and considered a promising therapeutic candidate for the treatment of obesity. FGF21 is predominantly produced by the liver but also by other tissues, such as white adipose tissue (WAT), brown adipose tissue (BAT), skeletal muscle, and pancreas in response to different stimuli such as cold and different nutritional challenges that include fasting, high-fat diets (HFDs), ketogenic diets, some amino acid-deficient diets, low protein diets, high carbohydrate diets or specific dietary bioactive compounds. Its target tissues are essentially WAT, BAT, skeletal muscle, heart and brain. The effects of FGF21 in extra hepatic tissues occur through the fibroblast growth factor receptor (FGFR)-1c together with the co-receptor β-klotho (KLB). Mechanistically, FGF21 interacts directly with the extracellular domain of the membrane bound cofactor KLB in the FGF21- KLB-FGFR complex to activate FGFR substrate 2α and ERK1/2 phosphorylation. Mice lacking KLB are resistant to both acute and chronic effects of FGF21. Moreover, the acute insulin sensitizing effects of FGF21 are also absent in mice with specific deletion of adipose KLB or FGFR1. Most of the data show that pharmacological administration of FGF21 has metabolic beneficial effects. The objective of this review is to compile existing information about the mechanisms that could allow the control of endogenous FGF21 levels in order to obtain the beneficial metabolic effects of FGF21 by inducing its production instead of doing it by pharmacological administration.
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30
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Maida A, Zota A, Sjøberg KA, Schumacher J, Sijmonsma TP, Pfenninger A, Christensen MM, Gantert T, Fuhrmeister J, Rothermel U, Schmoll D, Heikenwälder M, Iovanna JL, Stemmer K, Kiens B, Herzig S, Rose AJ. A liver stress-endocrine nexus promotes metabolic integrity during dietary protein dilution. J Clin Invest 2016; 126:3263-78. [PMID: 27548521 PMCID: PMC5004939 DOI: 10.1172/jci85946] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 07/07/2016] [Indexed: 02/06/2023] Open
Abstract
Dietary protein intake is linked to an increased incidence of type 2 diabetes (T2D). Although dietary protein dilution (DPD) can slow the progression of some aging-related disorders, whether this strategy affects the development and risk for obesity-associated metabolic disease such as T2D is unclear. Here, we determined that DPD in mice and humans increases serum markers of metabolic health. In lean mice, DPD promoted metabolic inefficiency by increasing carbohydrate and fat oxidation. In nutritional and polygenic murine models of obesity, DPD prevented and curtailed the development of impaired glucose homeostasis independently of obesity and food intake. DPD-mediated metabolic inefficiency and improvement of glucose homeostasis were independent of uncoupling protein 1 (UCP1), but required expression of liver-derived fibroblast growth factor 21 (FGF21) in both lean and obese mice. FGF21 expression and secretion as well as the associated metabolic remodeling induced by DPD also required induction of liver-integrated stress response-driven nuclear protein 1 (NUPR1). Insufficiency of select nonessential amino acids (NEAAs) was necessary and adequate for NUPR1 and subsequent FGF21 induction and secretion in hepatocytes in vitro and in vivo. Taken together, these data indicate that DPD promotes improved glucose homeostasis through an NEAA insufficiency-induced liver NUPR1/FGF21 axis.
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Affiliation(s)
- Adriano Maida
- Institute for Diabetes and Cancer (IDC), Helmholtz Center Munich, and Joint Heidelberg-IDC Translational Diabetes Program, Munich, Germany
| | - Annika Zota
- Institute for Diabetes and Cancer (IDC), Helmholtz Center Munich, and Joint Heidelberg-IDC Translational Diabetes Program, Munich, Germany
| | - Kim A. Sjøberg
- Section of Molecular Physiology, August Krogh Centre, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Jonas Schumacher
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, Heidelberg, Germany
| | - Tjeerd P. Sijmonsma
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, Heidelberg, Germany
- Division of Chronic Inflammation and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Anja Pfenninger
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt, Germany
| | - Marie M. Christensen
- Section of Molecular Physiology, August Krogh Centre, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Gantert
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, Heidelberg, Germany
| | - Jessica Fuhrmeister
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, Heidelberg, Germany
| | - Ulrike Rothermel
- Division of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany
| | - Dieter Schmoll
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt, Germany
| | - Mathias Heikenwälder
- Division of Chronic Inflammation and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Juan L. Iovanna
- Centre de Recherche en Cancérologie de Marseille, INSERM U1068, CNRS UMR 7258, Aix-Marseille Université and Institut Paoli-Calmettes, Parc Scientifique et Technologique de Luminy, Marseille, France
| | - Kerstin Stemmer
- Division of Metabolism and Cancer, Institute for Diabetes and Obesity, Helmholtz Centre Munich, Munich, Germany
| | - Bente Kiens
- Section of Molecular Physiology, August Krogh Centre, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Stephan Herzig
- Institute for Diabetes and Cancer (IDC), Helmholtz Center Munich, and Joint Heidelberg-IDC Translational Diabetes Program, Munich, Germany
| | - Adam J. Rose
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, Heidelberg, Germany
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Fibroblast growth factor 21 deficiency exacerbates chronic alcohol-induced hepatic steatosis and injury. Sci Rep 2016; 6:31026. [PMID: 27498701 PMCID: PMC4976373 DOI: 10.1038/srep31026] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 07/13/2016] [Indexed: 12/19/2022] Open
Abstract
Fibroblast growth factor 21 (FGF21) is a hepatokine that regulates glucose and lipid metabolism in the liver. We sought to determine the role of FGF21 in hepatic steatosis in mice exposed to chronic alcohol treatment and to discern underlying mechanisms. Male FGF21 knockout (FGF21 KO) and control (WT) mice were divided into groups that were fed either the Lieber DeCarli diet containing 5% alcohol or an isocaloric (control) diet for 4 weeks. One group of WT mice exposed to alcohol received recombinant human FGF21 (rhFGF21) in the last 5 days. Liver steatosis and inflammation were assessed. Primary mouse hepatocytes and AML-12 cells were incubated with metformin or rhFGF21. Hepatic genes and the products involved in in situ lipogenesis and fatty acid β-oxidation were analyzed. Alcohol exposure increased circulating levels and hepatic expression of FGF21. FGF21 depletion exacerbated alcohol-induced hepatic steatosis and liver injury, which was associated with increased activation of genes involved in lipogenesis mediated by SREBP1c and decreased expression of genes involved in fatty acid β-oxidation mediated by PGC1α. rhFGF21 administration reduced alcohol-induced hepatic steatosis and inflammation in WT mice. These results reveal that alcohol-induced FGF21 expression is a hepatic adaptive response to lipid dysregulation. Targeting FGF21 signaling could be a novel treatment approach for alcoholic steatohepatitis.
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Metabolic Responses to Dietary Protein Restriction Require an Increase in FGF21 that Is Delayed by the Absence of GCN2. Cell Rep 2016; 16:707-16. [PMID: 27396336 DOI: 10.1016/j.celrep.2016.06.044] [Citation(s) in RCA: 139] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 04/22/2016] [Accepted: 06/09/2016] [Indexed: 02/06/2023] Open
Abstract
FGF21 contributes to the metabolic response to dietary protein restriction, and prior data implicate GCN2 as the amino acid sensor linking protein restriction to FGF21 induction. Here, we demonstrate the persistent and essential role of FGF21 in the metabolic response to protein restriction. We show that Fgf21 KO mice are fully resistant to low protein (LP)-induced changes in food intake, energy expenditure (EE), body weight gain, and metabolic gene expression for 6 months. Gcn2 KO mice recapitulate this phenotype, but LP-induced effects on food intake, EE, and body weight subsequently begin to appear after 14 days on diet. We show that this delayed emergence of LP-induced metabolic effects in Gcn2 KO mice coincides with a delayed but progressive increase of hepatic Fgf21 expression and blood FGF21 concentrations over time. These data indicate that FGF21 is essential for the metabolic response to protein restriction but that GCN2 is only transiently required for LP-induced FGF21.
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Phillipson-Weiner L, Mirek ET, Wang Y, McAuliffe WG, Wek RC, Anthony TG. General control nonderepressible 2 deletion predisposes to asparaginase-associated pancreatitis in mice. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1061-70. [PMID: 26968207 PMCID: PMC4935488 DOI: 10.1152/ajpgi.00052.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/07/2016] [Indexed: 01/31/2023]
Abstract
Treatment with the antileukemic agent asparaginase can induce acute pancreatitis, but the pathophysiology remains obscure. In the liver of mice, eukaryotic initiation factor 2 (eIF2) kinase general control nonderepressible 2 (GCN2) is essential for mitigating metabolic stress caused by asparaginase. We determined the consequences of asparaginase treatment on the pancreata of wild-type (WT, GCN2-intact) and GCN2-deleted (ΔGcn2) mice. Mean pancreas weights in ΔGcn2 mice treated with asparaginase for 8 days were increased (P < 0.05) above all other groups. Histological examination revealed acinar cell swelling and altered staining of zymogen granules in ΔGcn2, but not WT, mice. Oil Red O staining and measurement of pancreas triglycerides excluded lipid accumulation as a contributor to acini appearance. Instead, transmission electron microscopy revealed dilatation of the endoplasmic reticulum (ER) and accumulation of autophagic vacuoles in the pancreas of ΔGcn2 mice treated with asparaginase. Consistent with the idea that loss of GCN2 in a pancreas exposed to asparaginase induced ER stress, phosphorylation of protein kinase R-like ER kinase (PERK) and its substrate eIF2 was increased in the pancreas of asparaginase-treated ΔGcn2 mice. In addition, mRNA expression of PERK target genes, activating transcription factors 4, 3, and 6 (Atf4, Atf3, and Atf6), fibroblast growth factor 21 (Fgf21), heat shock 70-kDa protein 5 (Hspa5), and spliced Xbp1 (sXbp1), as well as pancreas mass, was elevated in the pancreas of asparaginase-treated ΔGcn2 mice. Furthermore, genetic markers of oxidative stress [sirtuin (Sirt1)], inflammation [tumor necrosis factor-α (Tnfα)], and pancreatic injury [pancreatitis-associated protein (Pap)] were elevated in asparaginase-treated ΔGcn2, but not WT, mice. These data indicate that loss of GCN2 predisposes the exocrine pancreas to a maladaptive ER stress response and autophagy during asparaginase treatment and represent a genetic basis for development of asparaginase-associated pancreatitis.
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Affiliation(s)
- Lindsey Phillipson-Weiner
- 1Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey;
| | - Emily T. Mirek
- 1Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey;
| | - Yongping Wang
- 1Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey;
| | - W. Geoffrey McAuliffe
- 4Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, New Jersey; and
| | - Ronald C. Wek
- 5Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Tracy G. Anthony
- 1Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey; ,2Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey; ,3New Jersey Institute for Food, Nutrition, and Health, Rutgers, The State University of New Jersey, New Brunswick, New Jersey;
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Wanders D, Stone KP, Forney LA, Cortez CC, Dille KN, Simon J, Xu M, Hotard EC, Nikonorova IA, Pettit AP, Anthony TG, Gettys TW. Role of GCN2-Independent Signaling Through a Noncanonical PERK/NRF2 Pathway in the Physiological Responses to Dietary Methionine Restriction. Diabetes 2016; 65:1499-510. [PMID: 26936965 PMCID: PMC4878423 DOI: 10.2337/db15-1324] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 02/23/2016] [Indexed: 01/11/2023]
Abstract
Restricting availability of essential amino acids (EAAs) limits aminoacylation of tRNAs by their cognate EAAs and activates the nutrient-sensing kinase, general control nonderepressible 2 (GCN2). Activated GCN2 phosphorylates eukaryotic initiation factor 2 (eIF2), altering gene-specific translation and initiating a transcriptional program collectively described as the integrated stress response (ISR). Central GCN2 activation by EAA deprivation is also linked to an acute aversive feeding response. Dietary methionine restriction (MR) produces a well-documented series of physiological responses (increased energy intake and expenditure, decreased adiposity, and increased insulin sensitivity), but the role of GCN2 in mediating them is unknown. Using Gcn2(-/-) mice, we found that the absence of GCN2 had no effect on the ability of MR to reduce body weight or adiposity, increase energy intake and expenditure, increase hepatic transcription and release of fibroblast growth factor 21, or improve insulin sensitivity. Interestingly, hepatic eIF2 phosphorylation by MR was uncompromised in Gcn2(-/-) mice. Instead, protein kinase R-like endoplasmic reticulum (ER) kinase (PERK) was activated in both intact and Gcn2(-/-) mice. PERK activation corresponded with induction of the ISR and the nuclear respiratory factor 2 antioxidant program but not ER stress. These data uncover a novel glutathione-sensing mechanism that functions independently of GCN2 to link dietary MR to its metabolic phenotype.
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Affiliation(s)
- Desiree Wanders
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Kirsten P Stone
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Laura A Forney
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Cory C Cortez
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Kelly N Dille
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Jacob Simon
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Mark Xu
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Elisabeth C Hotard
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Inna A Nikonorova
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Ashley P Pettit
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Thomas W Gettys
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
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35
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Anthony TG. Homeostatic responses to amino acid insufficiency. ACTA ACUST UNITED AC 2015; 1:135-137. [PMID: 29767147 PMCID: PMC5945978 DOI: 10.1016/j.aninu.2015.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 10/16/2015] [Indexed: 12/14/2022]
Abstract
This article provides a brief overview describing how two key signaling pathways, namely the integrated stress response and the mammalian target of rapamycin complex 1, work together to facilitate cellular adaptation to dietary amino acid insufficiency. A deeper understanding of these mechanisms is leading to identification of novel targets which aid in disease treatments, improve stress recovery and increase health span through slowed aging and enhanced metabolic fitness.
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Affiliation(s)
- Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick 08901, USA
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36
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Morrison CD, Laeger T. Protein-dependent regulation of feeding and metabolism. Trends Endocrinol Metab 2015; 26:256-62. [PMID: 25771038 PMCID: PMC4416985 DOI: 10.1016/j.tem.2015.02.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 02/19/2015] [Accepted: 02/23/2015] [Indexed: 01/01/2023]
Abstract
Free-feeding animals often face complex nutritional choices that require the balancing of competing nutrients, but the mechanisms driving macronutrient-specific food intake are poorly defined. A large number of behavioral studies indicate that both the quantity and quality of dietary protein can markedly influence food intake and metabolism, and that dietary protein intake may be prioritized over energy intake. This review focuses on recent progress in defining the mechanisms underlying protein-specific feeding. Considering the evidence that protein powerfully regulates both food intake and metabolism, uncovering these protein-specific mechanisms may reveal new molecular targets for the treatment of obesity and diabetes while also offering a more complete understanding of how dietary factors shape both food intake and food choice.
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Affiliation(s)
| | - Thomas Laeger
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
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