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Jiang Q, Xiao J, Hsieh YC, Kumar NL, Han L, Zou Y, Li H. The Role of the PI3K/Akt/mTOR Axis in Head and Neck Squamous Cell Carcinoma. Biomedicines 2024; 12:1610. [PMID: 39062182 PMCID: PMC11274428 DOI: 10.3390/biomedicines12071610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Revised: 07/15/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies globally, representing a significant public health problem with a poor prognosis. The development of efficient therapeutic strategies for HNSCC prevention and treatment is urgently needed. The PI3K/AKT/mTOR (PAM) signaling pathway is a highly conserved transduction network in eukaryotic cells that promotes cell survival, growth, and cycle progression. Dysfunction in components of this pathway, such as hyperactivity of PI3K, loss of PTEN function, and gain-of-function mutations in AKT, are well-known drivers of treatment resistance and disease progression in cancer. In this review, we discuss the major mutations and dysregulations in the PAM signaling pathway in HNSCC. We highlight the results of clinical trials involving inhibitors targeting the PAM signaling pathway as a strategy for treating HNSCC. Additionally, we examine the primary mechanisms of resistance to drugs targeting the PAM pathway and potential therapeutic strategies.
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Affiliation(s)
- Qian Jiang
- Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Institute of Stomatology, Nanjing University, Nanjing 210093, China; (Q.J.)
- International Dentist Pathway, University of California, San Francisco, CA 94158, USA
| | - Jingyi Xiao
- Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Institute of Stomatology, Nanjing University, Nanjing 210093, China; (Q.J.)
| | - Yao-Ching Hsieh
- International Dentist Pathway, University of California, San Francisco, CA 94158, USA
| | - Neha Love Kumar
- International Dentist Pathway, University of California, San Francisco, CA 94158, USA
| | - Lei Han
- Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Institute of Stomatology, Nanjing University, Nanjing 210093, China; (Q.J.)
| | - Yuntao Zou
- Division of Hospital Medicine, University of California, San Francisco, CA 94158, USA
| | - Huang Li
- Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Institute of Stomatology, Nanjing University, Nanjing 210093, China; (Q.J.)
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Cao S, Jurczak MJ, Shuda Y, Sun R, Shuda M, Chang Y, Moore PS. Mitotic CDK1 and 4E-BP1 II: A single phosphomimetic mutation in 4E-BP1 induces glucose intolerance in mice. PLoS One 2023; 18:e0282914. [PMID: 36897840 PMCID: PMC10004604 DOI: 10.1371/journal.pone.0282914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 02/24/2023] [Indexed: 03/11/2023] Open
Abstract
OBJECTIVE Cyclin-dependent kinase 1 (CDK1)/cyclin B1 phosphorylates many of the same substrates as mTORC1 (a key regulator of glucose metabolism), including the eukaryotic initiation factor 4E-binding protein 1 (4E-BP1). Only mitotic CDK1 phosphorylates 4E-BP1 at residue S82 in mice (S83 in humans), in addition to the common 4E-BP1 phospho-acceptor sites phosphorylated by both CDK1 and mTORC1. We examined glucose metabolism in mice having a single aspartate phosphomimetic amino acid knock in substitution at the 4E-BP1 serine 82 (4E-BP1S82D) mimicking constitutive CDK1 phosphorylation. METHODS Knock-in homozygous 4E-BP1S82D and 4E-BP1S82A C57Bl/6N mice were assessed for glucose tolerance testing (GTT) and metabolic cage analysis on regular and on high-fat chow diets. Gastrocnemius tissues from 4E-BP1S82D and WT mice were subject to Reverse Phase Protein Array analysis. Since the bone marrow is one of the few tissues typically having cycling cells that transit mitosis, reciprocal bone-marrow transplants were performed between male 4E-BP1S82D and WT mice, followed by metabolic assessment, to determine the role of actively cycling cells on glucose homeostasis. RESULTS Homozygous knock-in 4E-BP1S82D mice showed glucose intolerance that was markedly accentuated with a diabetogenic high-fat diet (p = 0.004). In contrast, homozygous mice with the unphosphorylatable alanine substitution (4E-BP1S82A) had normal glucose tolerance. Protein profiling of lean muscle tissues, largely arrested in G0, did not show protein expression or signaling changes that could account for these results. Reciprocal bone-marrow transplantation between 4E-BP1S82D and wild-type littermates revealed a trend for wild-type mice with 4E-BP1S82D marrow engraftment on high-fat diets to become hyperglycemic after glucose challenge. CONCLUSIONS 4E-BP1S82D is a single amino acid substitution that induces glucose intolerance in mice. These findings indicate that glucose metabolism may be regulated by CDK1 4E-BP1 phosphorylation independent from mTOR and point towards an unexpected role for cycling cells that transit mitosis in diabetic glucose control.
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Affiliation(s)
- Simon Cao
- Hillman Cancer Center, Cancer Virology Program, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Michael J. Jurczak
- Division of Endocrinology and Metabolism, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Yoko Shuda
- Hillman Cancer Center, Cancer Virology Program, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Rui Sun
- Hillman Cancer Center, Cancer Virology Program, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Masahiro Shuda
- Hillman Cancer Center, Cancer Virology Program, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Yuan Chang
- Hillman Cancer Center, Cancer Virology Program, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Patrick S. Moore
- Hillman Cancer Center, Cancer Virology Program, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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Fajardo L, Sanchez P, Salles J, Rigaudière JP, Patrac V, Caspar-Bauguil S, Bergoglgio C, Moro C, Walrand S, Le Bacquer O. Inhibition of the endocannabinoid system reverses obese phenotype in aged mice and partly restores skeletal muscle function. Am J Physiol Endocrinol Metab 2023; 324:E176-E184. [PMID: 36629822 DOI: 10.1152/ajpendo.00258.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Sarcopenia, the age-related loss of skeletal muscle mass, is associated with lipid accumulation and anabolic resistance; phenomena also observed in obesity and worsen when obesity and aging are combined. The endocannabinoid system (ECS) is overactivated in obesity, but its role in aging obesity-related muscle dysfunction is unknown. The aims of this study were to evaluate the effect of inhibition of the ECS by rimonabant (RIM) on the metabolic alterations induced by a high-fat high-sucrose diet and on skeletal muscle mass/function in aged mice. Eighteen-month-old male mice were subjected to a control (CTL) or a high-fat high-sucrose (HFHS) diet for 24 weeks. Mice were administered with saline or RIM (10 mg/kg/day) for the last 4 weeks of the diet. Skeletal muscle function was evaluated by open-field, rotarod, and grip strength tests. Metabolic alterations in liver, adipose tissue, and skeletal muscle were investigated by quantitative RT-PCR. Body mass was higher in HFHS mice compared to CTL mice (48.0 ± 1.5 vs. 33.5 ± 0.7 g, P < 0.01), as a result of fat accumulation (34.8 ± 1.0 vs. 16.7 ± 0.8%, P < 0.01). RIM reduced body fat mass in both CTL (-16%, P < 0.05) and HFHS conditions (-40%, P < 0.01), without affecting hindlimb skeletal muscle mass. In HFHS mice, grip strength evolution was improved (-0.29 ± 0.06 vs. -0.49 ± 0.06 g/g lean mass, P < 0.05), and rotarod activity was increased by ≈60% in response to RIM (45.9 ± 6.3 vs. 28.5 ± 4.6 cm, P < 0.05). Lipolysis and β-oxidation genes were upregulated in the liver as well as genes involved in adipose tissue browning. These results demonstrate that inhibition of the ECS induces metabolic changes in liver and adipose tissue associated with a reversion of the obese phenotype and that RIM is able to improve motor coordination and muscle strength in aged mice, without affecting skeletal muscle mass.NEW & NOTEWORTHY In 24-month-old mice submitted to high-fat high-sucrose-induced obesity, inhibition of the endocannabinoid system by rimonabant reversed the obese phenotype by promoting adipose tissue browning and β-oxidation in the liver but not in skeletal muscle. These metabolism modifications are associated with improved skeletal muscle function.
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Affiliation(s)
- Lucas Fajardo
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - Phelipe Sanchez
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - Jérôme Salles
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - Jean Paul Rigaudière
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - Véronique Patrac
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - Sylvie Caspar-Bauguil
- Team MetaDiab, Institute of Metabolic and Cardiovascular Diseases (I2MC), Inserm/Paul Sabatier University UMR1297, Toulouse, France
- Department of Clinical Biochemistry, Toulouse University Hospitals, Toulouse, France
| | - Camille Bergoglgio
- Team MetaDiab, Institute of Metabolic and Cardiovascular Diseases (I2MC), Inserm/Paul Sabatier University UMR1297, Toulouse, France
| | - Cédric Moro
- Team MetaDiab, Institute of Metabolic and Cardiovascular Diseases (I2MC), Inserm/Paul Sabatier University UMR1297, Toulouse, France
| | - Stéphane Walrand
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
- Service de Nutrition Clinique, Hôpital Gabriel Montpied, Centre Hospitalier Universitaire (CHU) Clermont-Ferrand, Clermont-Ferrand, France
| | - Olivier Le Bacquer
- Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
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Kincheloe GN, Roberson PA, Toro AL, Stanley BA, Stanley AE, Jefferson LS, Dennis MD, Kimball SR. Loss of 4E-BPs prevents the hindlimb immobilization-induced decrease in protein synthesis in skeletal muscle. J Appl Physiol (1985) 2023; 134:72-83. [PMID: 36454675 PMCID: PMC9799152 DOI: 10.1152/japplphysiol.00563.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/30/2022] [Accepted: 11/30/2022] [Indexed: 12/05/2022] Open
Abstract
The present study was designed to test the hypothesis that upregulating protein synthesis attenuates the loss of muscle mass in a model of disuse atrophy. The studies compared the effect of unilateral hindlimb immobilization in wild-type (WT) mice and double-knockout (DKO) mice lacking the translational regulators 4E-BP1 and 4E-BP2. Immobilization-induced downregulation of protein synthesis occurred in both groups of mice, but protein synthesis was higher in gastrocnemius muscle from the immobilized hindlimb of fasted DKO compared with WT mice. Surprisingly, although protein synthesis was partially elevated in DKO compared with WT mice, atrophy occurred to the same extent in both groups of animals. This may be partially due to impaired leucine-induced stimulation of protein synthesis in DKO compared with WT mice due to downregulated eukaryotic initiation factor eIF4E expression in muscle of DKO compared with WT mice. Expression of the E3 ubiquitin ligases MAFbx and MuRF-1 mRNAs and total protein ubiquitylation was upregulated in the immobilized compared with the nonimmobilized hindlimb of both WT and DKO mice, with little difference in the magnitude of the upregulation between genotypes. Analysis of newly synthesized proteins revealed downregulation of several glycolytic enzymes in the gastrocnemius of DKO mice compared with WT mice, as well as in the immobilized compared with the nonimmobilized hindlimb. Overall, the results suggest that the elevated rate of protein synthesis during hindlimb immobilization in fasted DKO mice is insufficient to prevent disuse-induced muscle atrophy, probably due to induction of compensatory mechanisms including downregulation of eIF4E expression.NEW & NOTEWORTHY Basal rates of protein synthesis are elevated in skeletal muscle in the immobilized leg of mice lacking the translational repressors, 4E-BP1 and 4E-BP2 (knockout mice), compared with wild-type mice. However, disuse-induced muscle atrophy occurs to the same extent in both wild-type and knockout mice suggesting that compensatory mechanisms are induced that overcome the upregulation of muscle protein synthesis. Proteomic analysis revealed that mRNAs encoding several glycolytic enzymes are differentially translated in wild-type and knockout mice.
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Affiliation(s)
- Gregory N Kincheloe
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Paul A Roberson
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Allyson L Toro
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Bruce A Stanley
- Mass Spectrometry & Proteomics Core, Penn State College of Medicine, Hershey, Pennsylvania
| | - Anne E Stanley
- Mass Spectrometry & Proteomics Core, Penn State College of Medicine, Hershey, Pennsylvania
| | - Leonard S Jefferson
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Michael D Dennis
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Scot R Kimball
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
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Wang J, Eming SA, Ding X. Role of mTOR Signaling Cascade in Epidermal Morphogenesis and Skin Barrier Formation. BIOLOGY 2022; 11:biology11060931. [PMID: 35741452 PMCID: PMC9220260 DOI: 10.3390/biology11060931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/13/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary The skin epidermis is a stratified multilayered epithelium that provides a life-sustaining protective and defensive barrier for our body. The barrier machinery is established and maintained through a tightly regulated keratinocyte differentiation program. Under normal conditions, the basal layer keratinocytes undergo active proliferation and migration upward, differentiating into the suprabasal layer cells. Perturbation of the epidermal differentiation program often results in skin barrier defects and inflammatory skin disorders. The protein kinase mechanistic target of rapamycin (mTOR) is the central hub of cell growth, metabolism and nutrient signaling. Over the past several years, we and others using transgenic mouse models have unraveled that mTOR signaling is critical for epidermal differentiation and barrier formation. On the other hand, there is increasing evidence that disturbed activation of mTOR signaling is significantly implicated in the development of various skin diseases. In this review, we focus on the formation of skin barrier and discuss the current understanding on how mTOR signaling networks, including upstream inputs, kinases and downstream effectors, regulate epidermal differentiation and skin barrier formation. We hope this review will help us better understand the metabolic signaling in the epidermis, which may open new vistas for epidermal barrier defect-associated disease therapy. Abstract The skin epidermis, with its capacity for lifelong self-renewal and rapid repairing response upon injury, must maintain an active status in metabolism. Mechanistic target of rapamycin (mTOR) signaling is a central controller of cellular growth and metabolism that coordinates diverse physiological and pathological processes in a variety of tissues and organs. Recent evidence with genetic mouse models highlights an essential role of the mTOR signaling network in epidermal morphogenesis and barrier formation. In this review, we focus on the recent advances in understanding how mTOR signaling networks, including upstream inputs, kinases and downstream effectors, regulate epidermal morphogenesis and skin barrier formation. Understanding the details of the metabolic signaling will be critical for the development of novel pharmacological approaches to promote skin barrier regeneration and to treat epidermal barrier defect-associated diseases.
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Affiliation(s)
- Juan Wang
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong 226011, China;
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai 200444, China
| | - Sabine A. Eming
- Department of Dermatology, University of Cologne, 50937 Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50674 Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
- Institute of Zoology, Developmental Biology Unit, University of Cologne, 50674 Cologne, Germany
- Correspondence: (S.A.E.); (X.D.); Tel.: +86-137-6457-1130 (X.D.)
| | - Xiaolei Ding
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong 226011, China;
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai 200444, China
- Department of Dermatology, University of Cologne, 50937 Cologne, Germany
- Correspondence: (S.A.E.); (X.D.); Tel.: +86-137-6457-1130 (X.D.)
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Welles JE, Lacko H, Kawasawa YI, Dennis MD, Jefferson LS, Kimball SR. An integrative approach to assessing effects of a short-term Western diet on gene expression in rat liver. Front Endocrinol (Lausanne) 2022; 13:1032293. [PMID: 36387860 PMCID: PMC9643360 DOI: 10.3389/fendo.2022.1032293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 10/12/2022] [Indexed: 12/05/2022] Open
Abstract
Consumption of a diet rich in saturated fatty acids and carbohydrates contributes to the accumulation of fat in the liver and development of non-alcoholic steatohepatitis (NASH). Herein we investigated the hypothesis that short-term consumption of a high fat/sucrose Western diet (WD) alters the genomic and translatomic profile of the liver in association with changes in signaling through the protein kinase mTORC1, and that such alterations contribute to development of NAFLD. The results identify a plethora of mRNAs that exhibit altered expression and/or translation in the liver of rats consuming a WD compared to a CD. In particular, consumption of a WD altered the abundance and ribosome association of mRNAs involved in lipid and fatty acid metabolism, as well as those involved in glucose metabolism and insulin signaling. Hepatic mTORC1 signaling was enhanced when rats were fasted overnight and then refed in the morning; however, this effect was blunted in rats fed a WD as compared to a CD. Despite similar plasma insulin concentrations, fatty acid content was elevated in the liver of rats fed a WD as compared to a CD. We found that feeding had a significant positive effect on ribosome occupancy of 49 mRNAs associated with hepatic steatosis (e.g., LIPE, LPL), but this effect was blunted in the liver of rats fed a WD. In many cases, changes in ribosome association were independent of alterations in mRNA abundance, suggesting a critical role for diet-induced changes in mRNA translation in the expression of proteins encoded by those mRNAs. Overall, the findings demonstrate that short-term consumption of a WD impacts hepatic gene expression by altering the abundance of many mRNAs, but also causes wide-spread variation in mRNA translation that potentially contribute to development of hepatic steatosis.
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Affiliation(s)
- Jaclyn E. Welles
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, United States
| | - Holly Lacko
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, United States
| | - Yuka Imamura Kawasawa
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA, United States
| | - Michael D. Dennis
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, United States
| | - Leonard S. Jefferson
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, United States
| | - Scot R. Kimball
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, United States
- *Correspondence: Scot R. Kimball,
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Anderson R, Agarwal A, Ghosh A, Guan B, Casteel J, Dvorina N, Baldwin WM, Mazumder B, Nazarko TY, Merrick WC, Buchner DA, Hatzoglou M, Kondratov RV, Komar AA. eIF2A-knockout mice reveal decreased life span and metabolic syndrome. FASEB J 2021; 35:e21990. [PMID: 34665898 PMCID: PMC8848898 DOI: 10.1096/fj.202101105r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/02/2021] [Accepted: 09/29/2021] [Indexed: 01/07/2023]
Abstract
Eukaryotic initiation factor 2A (eIF2A) is a 65 kDa protein that functions in minor initiation pathways, which affect the translation of only a subset of messenger ribonucleic acid (mRNAs), such as internal ribosome entry site (IRES)-containing mRNAs and/or mRNAs harboring upstream near cognate/non-AUG start codons. These non-canonical initiation events are important for regulation of protein synthesis during cellular development and/or the integrated stress response. Selective eIF2A knockdown in cellular systems significantly inhibits translation of such mRNAs, which rely on alternative initiation mechanisms for their translation. However, there exists a gap in our understanding of how eIF2A functions in mammalian systems in vivo (on the organismal level) and ex vivo (in cells). Here, using an eIF2A-knockout (KO) mouse model, we present evidence implicating eIF2A in the biology of aging, metabolic syndrome and central tolerance. We discovered that eIF2A-KO mice have reduced life span and that eIF2A plays an important role in maintenance of lipid homeostasis, the control of glucose tolerance, insulin resistance and also reduces the abundance of B lymphocytes and dendritic cells in the thymic medulla of mice. We also show the eIF2A KO affects male and female mice differently, suggesting that eIF2A may affect sex-specific pathways. Interestingly, our experiments involving pharmacological induction of endoplasmic reticulum (ER) stress with tunicamycin did not reveal any substantial difference between the response to ER stress in eIF2A-KO and wild-type mice. The identification of eIF2A function in the development of metabolic syndrome bears promise for the further identification of specific eIF2A targets responsible for these changes.
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Affiliation(s)
- Richard Anderson
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | - Anchal Agarwal
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | - Arnab Ghosh
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | - Bo‐Jhih Guan
- Department of Genetics and Genome SciencesCase Western Reserve University School of MedicineClevelandOhioUSA
| | - Jackson Casteel
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | - Nina Dvorina
- Department of Inflammation and ImmunityCleveland Clinic Lerner College of MedicineClevelandOhioUSA
| | - William M. Baldwin
- Department of Inflammation and ImmunityCleveland Clinic Lerner College of MedicineClevelandOhioUSA
| | - Barsanjit Mazumder
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | | | - William C. Merrick
- Department of BiochemistryCase Western Reserve University School of MedicineClevelandOhioUSA
| | - David A. Buchner
- Department of Genetics and Genome SciencesCase Western Reserve University School of MedicineClevelandOhioUSA,Department of BiochemistryCase Western Reserve University School of MedicineClevelandOhioUSA
| | - Maria Hatzoglou
- Department of Genetics and Genome SciencesCase Western Reserve University School of MedicineClevelandOhioUSA
| | - Roman V. Kondratov
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA
| | - Anton A. Komar
- Center for Gene Regulation in Health and DiseaseDepartment of Biological, Geological and Environmental SciencesCleveland State UniversityClevelandOhioUSA,Department of BiochemistryCase Western Reserve University School of MedicineClevelandOhioUSA
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8
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Nie X, Ricupero CL, Jiao K, Yang P, Mao JJ. mTOR deletion in neural crest cells disrupts cardiac outflow tract remodeling and causes a spectrum of cardiac defects through the mTORC1 pathway. Dev Biol 2021; 477:241-250. [PMID: 34052210 DOI: 10.1016/j.ydbio.2021.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 04/17/2021] [Accepted: 05/15/2021] [Indexed: 11/28/2022]
Abstract
A critical cell type participating in cardiac outflow tract development is a subpopulation of the neural crest cells, the cardiac neural crest cells (NCCs), whose defect causes a spectrum of cardiovascular abnormalities. Accumulating evidence indicates that mTOR, which belongs to the PI3K-related kinase family and impacts multiple signaling pathways in a variety of contexts, plays a pivotal role for NCC development. Here, we investigated functional roles of mTOR for cardiac neural crest development using several lines of mouse genetic models. We found that disruption of mTOR caused NCC defects and failure of cardiac outflow tract separation, which resulted in a spectrum of cardiac defects including persistent truncus arteriosus, ventricular septal defect and ventricular wall defect. Specifically, mutant neural crest cells showed reduced migration into the cardiac OFT and prematurely exited the cell cycle. A number of critical factors and fundamental signaling pathways, which are important for neural crest and cardiomyocyte development, were impaired. Moreover, actin dynamics was disrupted by mTOR deletion. Finally, by phenotyping the neural crest Rptor and Rictor knockout mice respectively, we demonstrate that mTOR acts principally through the mTORC1 pathway for cardiac neural crest cells. Altogether, these data established essential roles of mTOR for cardiac NCC development and imply that dysregulation of mTOR in NCCs may underline a spectrum of cardiac defects.
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Affiliation(s)
- Xuguang Nie
- Center for Birth Defects Research,Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA; College of Dental Medicine, Columbia University in the City of New York, New York, NY, USA.
| | - Christopher L Ricupero
- College of Dental Medicine, Columbia University in the City of New York, New York, NY, USA
| | - Kai Jiao
- University of Alabama at Birmingham, Department of Genetics and Genomic Sciences, Birmingham, AL, USA
| | - Peixin Yang
- Center for Birth Defects Research,Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jeremy J Mao
- College of Dental Medicine, Columbia University in the City of New York, New York, NY, USA.
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Conn CS, Yang H, Tom HJ, Ikeda K, Oses-Prieto JA, Vu H, Oguri Y, Nair S, Gill RM, Kajimura S, DeBerardinis RJ, Burlingame AL, Ruggero D. The major cap-binding protein eIF4E regulates lipid homeostasis and diet-induced obesity. Nat Metab 2021; 3:244-257. [PMID: 33619378 DOI: 10.1038/s42255-021-00349-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 01/19/2021] [Indexed: 12/18/2022]
Abstract
Obesity is a global epidemic leading to increased mortality and susceptibility to comorbidities, with few viable therapeutic interventions. A hallmark of disease progression is the ectopic deposition of lipids in the form of lipid droplets in vital organs such as the liver. However, the mechanisms underlying the dynamic storage and processing of lipids in peripheral organs remain an outstanding question. Here, we show an unexpected function for the major cap-binding protein, eIF4E, in high-fat-diet-induced obesity. In response to lipid overload, select networks of proteins involved in fat deposition are altered in eIF4E-deficient mice. Specifically, distinct messenger RNAs involved in lipid metabolic processing and storage pathways are enhanced at the translation level by eIF4E. Failure to translationally upregulate these mRNAs results in increased fatty acid oxidation, which enhances energy expenditure. We further show that inhibition of eIF4E phosphorylation genetically-and by a potent clinical compound-restrains weight gain following intake of a high-fat diet. Together, our study uncovers translational control of lipid processing as a driver of high-fat-diet-induced weight gain and provides a pharmacological target to treat obesity.
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Affiliation(s)
- Crystal S Conn
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA
- School of Medicine and Department of Urology, University of California, San Francisco, CA, USA
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Haojun Yang
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA.
- School of Medicine and Department of Urology, University of California, San Francisco, CA, USA.
| | - Harrison J Tom
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA
- School of Medicine and Department of Urology, University of California, San Francisco, CA, USA
| | - Kenji Ikeda
- Diabetes Center, University of California, San Francisco, CA, USA
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA
| | - Juan A Oses-Prieto
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Hieu Vu
- Children's Research Institute and Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yasuo Oguri
- Diabetes Center, University of California, San Francisco, CA, USA
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA
| | - Supna Nair
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Ryan M Gill
- Department of Pathology, University of California, San Francisco, CA, USA
| | - Shingo Kajimura
- Diabetes Center, University of California, San Francisco, CA, USA
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA
| | - Ralph J DeBerardinis
- Children's Research Institute and Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Howard Hughes Medical Institute, UT Southwestern Medical Center, Dallas, TX, USA
| | - Alma L Burlingame
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Davide Ruggero
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA.
- School of Medicine and Department of Urology, University of California, San Francisco, CA, USA.
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA.
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10
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Pearl D, Katsumura S, Amiri M, Tabatabaei N, Zhang X, Vinette V, Pang X, Beug ST, Kim SH, Jones LM, Robichaud N, Ong SG, Jia JJ, Ali H, Tremblay ML, Jaramillo M, Alain T, Morita M, Sonenberg N, Tahmasebi S. 4E-BP-Dependent Translational Control of Irf8 Mediates Adipose Tissue Macrophage Inflammatory Response. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 204:2392-2400. [PMID: 32213561 DOI: 10.4049/jimmunol.1900538] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 02/02/2020] [Indexed: 12/16/2022]
Abstract
Deregulation of mRNA translation engenders many human disorders, including obesity, neurodegenerative diseases, and cancer, and is associated with pathogen infections. The role of eIF4E-dependent translational control in macrophage inflammatory responses in vivo is largely unexplored. In this study, we investigated the involvement of the translation inhibitors eIF4E-binding proteins (4E-BPs) in the regulation of macrophage inflammatory responses in vitro and in vivo. We show that the lack of 4E-BPs exacerbates inflammatory polarization of bone marrow-derived macrophages and that 4E-BP-null adipose tissue macrophages display enhanced inflammatory gene expression following exposure to a high-fat diet (HFD). The exaggerated inflammatory response in HFD-fed 4E-BP-null mice coincides with significantly higher weight gain, higher Irf8 mRNA translation, and increased expression of IRF8 in adipose tissue compared with wild-type mice. Thus, 4E-BP-dependent translational control limits, in part, the proinflammatory response during HFD. These data underscore the activity of the 4E-BP-IRF8 axis as a paramount regulatory mechanism of proinflammatory responses in adipose tissue macrophages.
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Affiliation(s)
- Dana Pearl
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Sakie Katsumura
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Mehdi Amiri
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Negar Tabatabaei
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612
| | - Xu Zhang
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Valerie Vinette
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Xinhe Pang
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612
| | - Shawn T Beug
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Sung-Hoon Kim
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Laura M Jones
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Nathaniel Robichaud
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Sang-Ging Ong
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612
- Division of Cardiology, Department of Medicine, University of Illinois College of Medicine, Chicago, IL 60612
| | - Jian-Jun Jia
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Hamza Ali
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Michel L Tremblay
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Maritza Jaramillo
- Institut National de la Recherche Scientifique-Institut Armand-Frappier, Laval, Quebec H7V 1B7, Canada; and
| | - Tommy Alain
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 8L1, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Masahiro Morita
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229;
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan
| | - Nahum Sonenberg
- Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada;
- Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Soroush Tahmasebi
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612;
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11
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Le Bacquer O, Combe K, Patrac V, Ingram B, Combaret L, Dardevet D, Montaurier C, Salles J, Giraudet C, Guillet C, Sonenberg N, Boirie Y, Walrand S. 4E-BP1 and 4E-BP2 double knockout mice are protected from aging-associated sarcopenia. J Cachexia Sarcopenia Muscle 2019; 10:696-709. [PMID: 30927336 PMCID: PMC6596930 DOI: 10.1002/jcsm.12412] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/04/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Sarcopenia is the loss of muscle mass/function that occurs during the aging process. The links between mechanistic target of rapamycin (mTOR) activity and muscle development are largely documented, but the role of its downstream targets in the development of sarcopenia is poorly understood. Eukaryotic initiation factor 4E-binding proteins (4E-BPs) are targets of mTOR that repress mRNA translation initiation and are involved in the control of several physiological processes. However, their role in skeletal muscle is still poorly understood. The goal of this study was to assess how loss of 4E-BP1 and 4E-BP2 expression impacts skeletal muscle function and homeostasis in aged mice and to characterize the associated metabolic changes by metabolomic and lipidomic profiling. METHODS Twenty-four-month-old wild-type and whole body 4E-BP1/4E-BP2 double knockout (DKO) mice were used to measure muscle mass and function. Protein homeostasis was measured ex vivo in extensor digitorum longus by incorporation of l-[U-14 C]phenylalanine, and metabolomic and lipidomic profiling of skeletal muscle was performed by Metabolon, Inc. RESULTS The 4E-BP1/2 DKO mice exhibited an increase in muscle mass that was associated with increased grip strength (P < 0.05). Protein synthesis was higher under both basal (+102%, P < 0.05) and stimulated conditions (+65%, P < 0.05) in DKO skeletal muscle. Metabolomic and complex lipid analysis of skeletal muscle revealed robust differences pertaining to amino acid homeostasis, carbohydrate abundance, and certain aspects of lipid metabolism. In particular, levels of most free amino acids were lower within the 4E-BP1/2 DKO muscle. Interestingly, although glucose levels were unchanged, differences were observed in the isobaric compound maltitol/lactitol (33-fold increase, P < 0.01) and in several additional carbohydrate compounds. 4E-BP1/2 depletion also resulted in accumulation of medium-chain acylcarnitines and a 20% lower C2/C0 acylcarnitine ratio (P < 0.01) indicative of reduced β-oxidation. CONCLUSIONS Taken together, these findings demonstrate that deletion of 4E-BPs is associated with perturbed energy metabolism in skeletal muscle and could have beneficial effects on skeletal muscle mass and function in aging mice. They also identify 4E-BPs as potential targets for the treatment of sarcopenia.
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Affiliation(s)
- Olivier Le Bacquer
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Kristell Combe
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Véronique Patrac
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | | | - Lydie Combaret
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Dominique Dardevet
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Christophe Montaurier
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Jérôme Salles
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Christophe Giraudet
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Christelle Guillet
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | - Yves Boirie
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France.,CHU Clermont-Ferrand, Service Nutrition Clinique, Clermont-Ferrand, France
| | - Stéphane Walrand
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
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12
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Jiang B, Lv Q, Wan W, Le L, Xu L, Hu K, Xiao P. Transcriptome analysis reveals the mechanism of the effect of flower tea Coreopsis tinctoria on hepatic insulin resistance. Food Funct 2019; 9:5607-5620. [PMID: 30370909 DOI: 10.1039/c8fo00965a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Non-Camellia tea and herbal medicine help prevent the development of diabetes and other metabolic diseases. Previous studies revealed that Coreopsis tinctoria (CT) flower tea increases insulin sensitivity and, in some high-fat diet (HFD)-fed rats, even prevents hepatic metabolic disorders. However, the molecular mechanisms by which CT improves insulin resistance are not known. In this study, six-week-old rats were fed a normal diet (ND), an HFD or an HFD supplemented with CT for 8 weeks. Serum samples were collected, and the livers were extracted for RNA-seq gene expression analysis. Real-time PCR and western blotting further verified the RNA-seq results. In our results, dietary CT ameliorated HFD-induced hepatosteatosis, glucose intolerance, and insulin resistance. In the HFD group, 1667 differentially expressed genes (DEGs) were identified compared with the ND group. In the CT group, 327 DEGs were identified compared with the HFD group. Some of these DEGs were related to insulin signalling, hepatic lipogenesis and glucose homeostasis. This study suggested that insulin resistance with hyperinsulinaemia, and not insulin insufficiency, is an early problem in HFD-fed rats, and CT downregulates insulin secretion genes (e.g., Rasd1, Stxbp1 and Sfxn1). Hepatic gene and protein expression analyses indicated that the regulatory effects of CT on glucose and lipid homeostasis are likely mediated via the Akt/FoxO1 signalling pathway and are regulated by the transcription factors hairy and enhancer of split 1 (HES1) and small heterodimer partner (SHP). Our study provides transcriptomic evidence of the complex pathogenic mechanism involved in hepatic insulin resistance and proves that supplementation with CT improves insulin resistance at a global scale.
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Affiliation(s)
- Baoping Jiang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100193, China.
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