1
|
Smiles WJ, Ovens AJ, Oakhill JS, Kofler B. The metabolic sensor AMPK: Twelve enzymes in one. Mol Metab 2024; 90:102042. [PMID: 39362600 DOI: 10.1016/j.molmet.2024.102042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2024] [Revised: 09/12/2024] [Accepted: 09/27/2024] [Indexed: 10/05/2024] Open
Abstract
BACKGROUND AMP-activated protein kinase (AMPK) is an evolutionarily conserved regulator of energy metabolism. AMPK is sensitive to acute perturbations to cellular energy status and leverages fundamental bioenergetic pathways to maintain cellular homeostasis. AMPK is a heterotrimer comprised of αβγ-subunits that in humans are encoded by seven individual genes (isoforms α1, α2, β1, β2, γ1, γ2 and γ3), permitting formation of at least 12 different complexes with personalised biochemical fingerprints and tissue expression patterns. While the canonical activation mechanisms of AMPK are well-defined, delineation of subtle, as well as substantial, differences in the regulation of heterogenous AMPK complexes remain poorly defined. SCOPE OF REVIEW Here, taking advantage of multidisciplinary findings, we dissect the many aspects of isoform-specific AMPK function and links to health and disease. These include, but are not limited to, allosteric activation by adenine nucleotides and small molecules, co-translational myristoylation and post-translational modifications (particularly phosphorylation), governance of subcellular localisation, and control of transcriptional networks. Finally, we delve into current debate over whether AMPK can form novel protein complexes (e.g., dimers lacking the α-subunit), altogether highlighting opportunities for future and impactful research. MAJOR CONCLUSIONS Baseline activity of α1-AMPK is higher than its α2 counterpart and is more sensitive to synergistic allosteric activation by metabolites and small molecules. α2 complexes however, show a greater response to energy stress (i.e., AMP production) and appear to be better substrates for LKB1 and mTORC1 upstream. These differences may explain to some extent why in certain cancers α1 is a tumour promoter and α2 a suppressor. β1-AMPK activity is toggled by a 'myristoyl-switch' mechanism that likely precedes a series of signalling events culminating in phosphorylation by ULK1 and sensitisation to small molecules or endogenous ligands like fatty acids. β2-AMPK, not entirely beholden to this myristoyl-switch, has a greater propensity to infiltrate the nucleus, which we suspect contributes to its oncogenicity in some cancers. Last, the unique N-terminal extensions of the γ2 and γ3 isoforms are major regulatory domains of AMPK. mTORC1 may directly phosphorylate this region in γ2, although whether this is inhibitory, especially in disease states, is unclear. Conversely, γ3 complexes might be preferentially regulated by mTORC1 in response to physical exercise.
Collapse
Affiliation(s)
- William J Smiles
- Research Program for Receptor Biochemistry and Tumour Metabolism, Department of Paediatrics, University Hospital of the Paracelsus Medical University, Salzburg, Austria; Metabolic Signalling Laboratory, St. Vincent's Institute of Medical Research, Fitzroy, Melbourne, Australia.
| | - Ashley J Ovens
- Protein Engineering in Immunity & Metabolism, St. Vincent's Institute of Medical Research, Fitzroy, Melbourne, Australia
| | - Jonathan S Oakhill
- Metabolic Signalling Laboratory, St. Vincent's Institute of Medical Research, Fitzroy, Melbourne, Australia; Department of Medicine, University of Melbourne, Parkville, Australia
| | - Barbara Kofler
- Research Program for Receptor Biochemistry and Tumour Metabolism, Department of Paediatrics, University Hospital of the Paracelsus Medical University, Salzburg, Austria
| |
Collapse
|
2
|
Smith TKT, Ghorbani P, LeBlond ND, Nunes JRC, O'Dwyer C, Ambursley N, Fong-McMaster C, Minarrieta L, Burkovsky LA, El-Hakim R, Trzaskalski NA, Locatelli CAA, Stotts C, Pember C, Rayner KJ, Kemp BE, Loh K, Harper ME, Mulvihill EE, St-Pierre J, Fullerton MD. AMPK-mediated regulation of endogenous cholesterol synthesis does not affect atherosclerosis in a murine Pcsk9-AAV model. Atherosclerosis 2024; 397:117608. [PMID: 38880706 DOI: 10.1016/j.atherosclerosis.2024.117608] [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] [Received: 11/20/2023] [Revised: 05/09/2024] [Accepted: 05/30/2024] [Indexed: 06/18/2024]
Abstract
BACKGROUND AND AIMS Dysregulated cholesterol metabolism is a hallmark of atherosclerotic cardiovascular diseases, yet our understanding of how endogenous cholesterol synthesis affects atherosclerosis is not clear. The energy sensor AMP-activated protein kinase (AMPK) phosphorylates and inhibits the rate-limiting enzyme in the mevalonate pathway HMG-CoA reductase (HMGCR). Recent work demonstrated that when AMPK-HMGCR signaling was compromised in an Apoe-/- model of hypercholesterolemia, atherosclerosis was exacerbated due to elevated hematopoietic stem and progenitor cell mobilization and myelopoiesis. We sought to validate the significance of the AMPK-HMGCR signaling axis in atherosclerosis using a non-germline hypercholesterolemia model with functional ApoE. METHODS Male and female HMGCR S871A knock-in (KI) mice and wild-type (WT) littermate controls were made atherosclerotic by intravenous injection of a gain-of-function Pcsk9D374Y-adeno-associated virus followed by high-fat and high-cholesterol atherogenic western diet feeding for 16 weeks. RESULTS AMPK activation suppressed endogenous cholesterol synthesis in primary bone marrow-derived macrophages from WT but not HMGCR KI mice, without changing other parameters of cholesterol regulation. Atherosclerotic plaque area was unchanged between WT and HMGCR KI mice, independent of sex. Correspondingly, there were no phenotypic differences observed in hematopoietic progenitors or differentiated immune cells in the bone marrow, blood, or spleen, and no significant changes in systemic markers of inflammation. When lethally irradiated female mice were transplanted with KI bone marrow, there was similar plaque content relative to WT. CONCLUSIONS Given previous work, our study demonstrates the importance of preclinical atherosclerosis model comparison and brings into question the importance of AMPK-mediated control of cholesterol synthesis in atherosclerosis.
Collapse
Affiliation(s)
- Tyler K T Smith
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Peyman Ghorbani
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Nicholas D LeBlond
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Julia R C Nunes
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Conor O'Dwyer
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Nia Ambursley
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Claire Fong-McMaster
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Lucía Minarrieta
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Leah A Burkovsky
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Rama El-Hakim
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Natasha A Trzaskalski
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Cassandra A A Locatelli
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Cameron Stotts
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Ciara Pember
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Katey J Rayner
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Bruce E Kemp
- Protein Chemistry and Metabolism, St. Vincent's Institute of Medical Research, Fitzroy, Australia; Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia; Department of Medicine, University of Melbourne, Melbourne, Australia
| | - Kim Loh
- Diabetes and Metabolic Disease, St. Vincent's Institute of Medical Research, Fitzroy, Australia; Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia; Department of Medicine, University of Melbourne, Melbourne, Australia
| | - Mary-Ellen Harper
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Erin E Mulvihill
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Julie St-Pierre
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Morgan D Fullerton
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Centre for Infection, Immunity and Inflammation, Ottawa, ON, Canada; Centre for Catalysis Research and Innovation, Ottawa, ON, Canada; Ottawa Institute of Systems Biology, Ottawa, ON, Canada.
| |
Collapse
|
3
|
Freemantle JB, Shah D, Lynch DM, Ciulli A, Hundal HS, Hardie DG. The pro-drug C13 activates AMPK by two distinct mechanisms. Biochem J 2024; 481:1203-1219. [PMID: 39222030 DOI: 10.1042/bcj20240425] [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: 08/28/2024] [Revised: 08/28/2024] [Accepted: 09/02/2024] [Indexed: 09/04/2024]
Abstract
The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status that is expressed in almost all eukaryotic cells. In the canonical activation mechanism, it is activated by increases in AMP:ATP and ADP:ATP ratios that signify declining cellular energy status. Once activated, AMPK phosphorylates numerous targets that promote catabolic pathways generating ATP, while inhibiting anabolic and other processes that consume ATP, thus acting to restore energy homeostasis. Pharmacological agents that activate AMPK have been useful in identifying downstream targets and have potential as drugs for treatment of metabolic disorders such as Type 2 diabetes and non-alcoholic fatty liver disease. One such agent is C13, a pro-drug with a phosphonate bis(isobutyryloxymethyl) ester moiety, with the isobutyryloxymethyl groups increasing membrane permeability. Following cellular uptake, C13 is cleaved to release C2, an AMP analogue and potent AMPK activator that is specific for complexes containing the α1 (but not the α2) catalytic subunit isoform. This has previously been assumed to be the sole mechanism by which C13 activates AMPK, with potential roles for the isobutyryloxymethyl groups being ignored. We now report that, following cleavage from C13, these protective groups are metabolized to formaldehyde, an agent that inhibits mitochondrial function and increases cellular AMP:ATP ratios, thus providing additional AMPK activation by the canonical mechanism.
Collapse
Affiliation(s)
- Jordana B Freemantle
- Division of Cell Signalling and Immunology, Sir James Black Centre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Dinesh Shah
- Division of Cell Signalling and Immunology, Sir James Black Centre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Dylan M Lynch
- Centre for Targeted Protein Degradation, School of Life Sciences, University of Dundee, 1 James Lindsay Place, Dundee DD1 5JJ, U.K
| | - Alessio Ciulli
- Centre for Targeted Protein Degradation, School of Life Sciences, University of Dundee, 1 James Lindsay Place, Dundee DD1 5JJ, U.K
| | - Harinder S Hundal
- Division of Cell Signalling and Immunology, Sir James Black Centre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - D Grahame Hardie
- Division of Cell Signalling and Immunology, Sir James Black Centre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| |
Collapse
|
4
|
Thomas PA, Kinsey ST. Hypoxia Tolerance of Two Killifish Species. Integr Comp Biol 2024:icae144. [PMID: 39238158 DOI: 10.1093/icb/icae144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 08/04/2024] [Accepted: 08/14/2024] [Indexed: 09/07/2024] Open
Abstract
Hypoxia tolerance in aquatic ectotherms involves a suite of behavioral and physiological responses at the organismal, tissue, and cellular levels. The current study evaluated two closely related killifish species (Fundulus heteroclitus, Fundulus majalis) to evaluate responses to acute moderate and acute severe hypoxia. Routine metabolic rate and loss of equilibrium were assessed, followed by analysis in skeletal muscle of markers of oxidative damage to proteins (2,4-DNPH), lipids (4-HNE), and DNA (8-OHdG), hypoxia signaling (HIF1α, HIF2α), cellular energy state (p-AMPK: AMPK), and protein degradation (Ubiquitin, LC3B, Calpain 2, Hsp70). Both species had a similar reduction in metabolic rate at low PO2. However, F. heteroclitus was the more hypoxia-tolerant species based on a lower PO2 at which there was loss of equilibrium, perhaps due in part to a lower oxygen demand at all oxygen tensions. Despite the differences in hypoxia tolerance between the species, skeletal muscle molecular markers were largely insensitive to hypoxia, and there were few differences in responses between the species. Thus, the metabolic depression observed at the whole animal level appears to limit perturbations in skeletal muscle in both species during the hypoxia treatments.
Collapse
Affiliation(s)
- Peyton A Thomas
- Department of Biology and Marine Biology, University of North Carolina at Wilmington, Wilmington, NC 28403, USA
| | - Stephen T Kinsey
- Department of Biology and Marine Biology, University of North Carolina at Wilmington, Wilmington, NC 28403, USA
| |
Collapse
|
5
|
Yang H, Zingaro VA, Lincoff J, Tom H, Oikawa S, Oses-Prieto JA, Edmondson Q, Seiple I, Shah H, Kajimura S, Burlingame AL, Grabe M, Ruggero D. Remodelling of the translatome controls diet and its impact on tumorigenesis. Nature 2024; 633:189-197. [PMID: 39143206 DOI: 10.1038/s41586-024-07781-7] [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: 04/15/2023] [Accepted: 07/03/2024] [Indexed: 08/16/2024]
Abstract
Fasting is associated with a range of health benefits1-6. How fasting signals elicit changes in the proteome to establish metabolic programmes remains poorly understood. Here we show that hepatocytes selectively remodel the translatome while global translation is paradoxically downregulated during fasting7,8. We discover that phosphorylation of eukaryotic translation initiation factor 4E (P-eIF4E) is induced during fasting. We show that P-eIF4E is responsible for controlling the translation of genes involved in lipid catabolism and the production of ketone bodies. Inhibiting P-eIF4E impairs ketogenesis in response to fasting and a ketogenic diet. P-eIF4E regulates those messenger RNAs through a specific translation regulatory element within their 5' untranslated regions (5' UTRs). Our findings reveal a new signalling property of fatty acids, which are elevated during fasting. We found that fatty acids bind and induce AMP-activated protein kinase (AMPK) kinase activity that in turn enhances the phosphorylation of MAP kinase-interacting protein kinase (MNK), the kinase that phosphorylates eIF4E. The AMPK-MNK-eIF4E axis controls ketogenesis, revealing a new lipid-mediated kinase signalling pathway that links ketogenesis to translation control. Certain types of cancer use ketone bodies as an energy source9,10 that may rely on P-eIF4E. Our findings reveal that on a ketogenic diet, treatment with eFT508 (also known as tomivosertib; a P-eIF4E inhibitor) restrains pancreatic tumour growth. Thus, our findings unveil a new fatty acid-induced signalling pathway that activates selective translation, which underlies ketogenesis and provides a tailored diet intervention therapy for cancer.
Collapse
Affiliation(s)
- Haojun Yang
- Helen Diller Family Comprehensive Cancer Center, UCSF, San Francisco, CA, USA
- School of Medicine and Department of Urology, UCSF, San Francisco, CA, USA
| | - Vincenzo Andrea Zingaro
- Helen Diller Family Comprehensive Cancer Center, UCSF, San Francisco, CA, USA
- School of Medicine and Department of Urology, UCSF, San Francisco, CA, USA
| | - James Lincoff
- Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA, USA
- Cardiovascular Research Institute, UCSF, San Francisco, CA, USA
| | - Harrison Tom
- Helen Diller Family Comprehensive Cancer Center, UCSF, San Francisco, CA, USA
- School of Medicine and Department of Urology, UCSF, San Francisco, CA, USA
| | - Satoshi Oikawa
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School and Howard Hughes Medical Institute, Boston, MA, USA
| | | | - Quinn Edmondson
- Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA, USA
- Cardiovascular Research Institute, UCSF, San Francisco, CA, USA
| | - Ian Seiple
- Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA, USA
- Cardiovascular Research Institute, UCSF, San Francisco, CA, USA
| | - Hardik Shah
- Metabolomics Platform, Comprehensive Cancer Center, The University of Chicago, Chicago, IL, USA
| | - Shingo Kajimura
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School and Howard Hughes Medical Institute, Boston, MA, USA
| | - Alma L Burlingame
- Helen Diller Family Comprehensive Cancer Center, UCSF, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA, USA
| | - Michael Grabe
- Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA, USA
- Cardiovascular Research Institute, UCSF, San Francisco, CA, USA
| | - Davide Ruggero
- Helen Diller Family Comprehensive Cancer Center, UCSF, San Francisco, CA, USA.
- School of Medicine and Department of Urology, UCSF, San Francisco, CA, USA.
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, CA, USA.
| |
Collapse
|
6
|
Abukwaik R, Vera-Siguenza E, Tennant D, Spill F. p53 Orchestrates Cancer Metabolism: Unveiling Strategies to Reverse the Warburg Effect. Bull Math Biol 2024; 86:124. [PMID: 39207627 PMCID: PMC11362376 DOI: 10.1007/s11538-024-01346-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 07/30/2024] [Indexed: 09/04/2024]
Abstract
Cancer cells exhibit significant alterations in their metabolism, characterised by a reduction in oxidative phosphorylation (OXPHOS) and an increased reliance on glycolysis, even in the presence of oxygen. This metabolic shift, known as the Warburg effect, is pivotal in fuelling cancer's uncontrolled growth, invasion, and therapeutic resistance. While dysregulation of many genes contributes to this metabolic shift, the tumour suppressor gene p53 emerges as a master player. Yet, the molecular mechanisms remain elusive. This study introduces a comprehensive mathematical model, integrating essential p53 targets, offering insights into how p53 orchestrates its targets to redirect cancer metabolism towards an OXPHOS-dominant state. Simulation outcomes align closely with experimental data comparing glucose metabolism in colon cancer cells with wild-type and mutated p53. Additionally, our findings reveal the dynamic capability of elevated p53 activation to fully reverse the Warburg effect, highlighting the significance of its activity levels not just in triggering apoptosis (programmed cell death) post-chemotherapy but also in modifying the metabolic pathways implicated in treatment resistance. In scenarios of p53 mutations, our analysis suggests targeting glycolysis-instigating signalling pathways as an alternative strategy, whereas targeting solely synthesis of cytochrome c oxidase 2 (SCO2) does support mitochondrial respiration but may not effectively suppress the glycolysis pathway, potentially boosting the energy production and cancer cell viability.
Collapse
Affiliation(s)
- Roba Abukwaik
- Mathematics Department, King Abdulaziz University, Rabigh, Saudi Arabia.
- School of Mathematics, University of Birmingham, Birmingham, B15 2TS, UK.
| | - Elias Vera-Siguenza
- School of Mathematics, University of Birmingham, Birmingham, B15 2TS, UK
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, B15 2TT, UK
| | - Daniel Tennant
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, B15 2TT, UK
| | - Fabian Spill
- School of Mathematics, University of Birmingham, Birmingham, B15 2TS, UK.
| |
Collapse
|
7
|
Sirtori CR, Castiglione S, Pavanello C. METFORMIN: FROM DIABETES TO CANCER TO PROLONGATION OF LIFE. Pharmacol Res 2024; 208:107367. [PMID: 39191336 DOI: 10.1016/j.phrs.2024.107367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 08/12/2024] [Accepted: 08/21/2024] [Indexed: 08/29/2024]
Abstract
The metformin molecule dates back to over a century, but its clinical use started in the '50s. Since then, its use in diabetics has grown constantly, with over 150 million users today. The therapeutic profile also expanded, with improved understanding of novel mechanisms. Metformin has a major activity on insulin resistance, by acting on the insulin receptors and mitochondria, most likely by activation of the adenosine monophosphate-activated kinase. These and associated mechanisms lead to significant lipid lowering and body weight loss. An anti-cancer action has come up in recent years, with mechanisms partly dependent on the mitochondrial activity and also on phosphatidylinositol 3-kinase resistance occurring in some malignant tumors. The potential of metformin to raise life-length is the object of large ongoing studies and of several basic and clinical investigations. The present review article will attempt to investigate the basic mechanisms behind these diverse activities and the potential clinical benefits. Metformin may act on transcriptional activity by histone modification, DNA methylation and miRNAs. An activity on age-associated inflammation (inflammaging) may occur via activation of the nuclear factor erythroid 2 related factor and changes in gut microbiota. A senolytic activity, leading to reduction of cells with the senescent associated secretory phenotype, may be crucial in lifespan prolongation as well as in ancillary properties in age-associated diseases, such as Parkinson's disease. Telomere prolongation may be related to the activity on mitochondrial respiratory factor 1 and on peroxisome gamma proliferator coactivator 1-alpha. Very recent observations on the potential to act on the most severe neurological disorders, such as amyotrophic lateral sclerosis and frontotemporal dementia, have raised considerable hope.
Collapse
Affiliation(s)
- Cesare R Sirtori
- Center of Dyslipidemias, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy; Centro E. Grossi Paoletti, Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
| | - Sofia Castiglione
- Center of Dyslipidemias, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy; Centro E. Grossi Paoletti, Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Chiara Pavanello
- Center of Dyslipidemias, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy; Centro E. Grossi Paoletti, Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| |
Collapse
|
8
|
Xu Y, Bai L, Yang X, Huang J, Wang J, Wu X, Shi J. Recent advances in anti-inflammation via AMPK activation. Heliyon 2024; 10:e33670. [PMID: 39040381 PMCID: PMC11261115 DOI: 10.1016/j.heliyon.2024.e33670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 06/22/2024] [Accepted: 06/25/2024] [Indexed: 07/24/2024] Open
Abstract
Inflammation is a complex physiological phenomenon, which is the body's defensive response, but abnormal inflammation can have adverse effects, and many diseases are related to the inflammatory response. AMPK, as a key sensor of cellular energy status, plays a crucial role in regulating cellular energy homeostasis and glycolipid metabolism. In recent years, the anti-inflammation effect of AMPK and related signalling cascade has begun to enter everyone's field of vision - not least the impact on metabolic diseases. A great number of studies have shown that anti-inflammatory drugs work through AMPK and related pathways. Herein, this article summarises recent advances in compounds that show anti-inflammatory effects by activating AMPK and attempts to comment on them.
Collapse
Affiliation(s)
- Yihua Xu
- School of Basic Medical Science, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Lan Bai
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, China
- The State Key Laboratory of Southwestern Chinese Medicine Resources, Department of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Xinwei Yang
- School of Sports Medicine and Health, Chengdu Sport University, Chengdu, Sichuan, China
| | - Jianli Huang
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Jie Wang
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Xianbo Wu
- School of Sports Medicine and Health, Chengdu Sport University, Chengdu, Sichuan, China
| | - Jianyou Shi
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, China
- The State Key Laboratory of Southwestern Chinese Medicine Resources, Department of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| |
Collapse
|
9
|
Smiles WJ, Ovens AJ, Kemp BE, Galic S, Petersen J, Oakhill JS. New developments in AMPK and mTORC1 cross-talk. Essays Biochem 2024:EBC20240007. [PMID: 38994736 DOI: 10.1042/ebc20240007] [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: 05/09/2024] [Revised: 06/27/2024] [Accepted: 06/28/2024] [Indexed: 07/13/2024]
Abstract
Metabolic homeostasis and the ability to link energy supply to demand are essential requirements for all living cells to grow and proliferate. Key to metabolic homeostasis in all eukaryotes are AMPK and mTORC1, two kinases that sense nutrient levels and function as counteracting regulators of catabolism (AMPK) and anabolism (mTORC1) to control cell survival, growth and proliferation. Discoveries beginning in the early 2000s revealed that AMPK and mTORC1 communicate, or cross-talk, through direct and indirect phosphorylation events to regulate the activities of each other and their shared protein substrate ULK1, the master initiator of autophagy, thereby allowing cellular metabolism to rapidly adapt to energy and nutritional state. More recent reports describe divergent mechanisms of AMPK/mTORC1 cross-talk and the elaborate means by which AMPK and mTORC1 are activated at the lysosome. Here, we provide a comprehensive overview of current understanding in this exciting area and comment on new evidence showing mTORC1 feedback extends to the level of the AMPK isoform, which is particularly pertinent for some cancers where specific AMPK isoforms are implicated in disease pathogenesis.
Collapse
Affiliation(s)
- William J Smiles
- Metabolic Signalling Laboratory, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
- Research Program for Receptor Biochemistry and Tumour Metabolism, Department of Paediatrics, University Hospital of the Paracelsus Medical University, Salzburg, Austria
| | - Ashley J Ovens
- Protein Engineering in Immunity and Metabolism, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Bruce E Kemp
- Protein Chemistry and Metabolism, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
- Department of Medicine, University of Melbourne, Parkville, VIC 3010, Australia
- Mary Mackillop Institute for Health Research, Australian Catholic University, Fitzroy, Vic 3065, Vic. Australia
| | - Sandra Galic
- Department of Medicine, University of Melbourne, Parkville, VIC 3010, Australia
- Metabolic Physiology, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Janni Petersen
- Flinders Health and Medical Research Institute, Flinders Centre for Innovation in Cancer, Flinders University, Adelaide, SA 5042, Australia
- Nutrition and Metabolism, South Australia Health and Medical Research Institute, Adelaide, SA 5000, Australia
| | - Jonathan S Oakhill
- Metabolic Signalling Laboratory, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
- Department of Medicine, University of Melbourne, Parkville, VIC 3010, Australia
| |
Collapse
|
10
|
Taha M, Houchat JN, Taillebois E, Thany SH. The calcium-calmodulin-dependent protein kinase kinase inhibitor, STO-609, inhibits nicotine-induced currents and intracellular calcium increase in insect neurosecretory cells. J Neurochem 2024; 168:1281-1296. [PMID: 38339787 DOI: 10.1111/jnc.16077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 02/12/2024]
Abstract
Insect neuronal nicotinic acetylcholine receptors (nAChRs) are transmembrane receptors that play a key role in the development and synaptic plasticity of both vertebrates and invertebrates and are considered to be major targets of neonicotinoid insecticides. We used dorsal unpaired median (DUM) neurons, which are insect neurosecretory cells, in order to explore the intracellular mechanisms leading to the regulation of insect neuronal nAChRs in more detail. Using whole-cell patch-clamp and fura-2AM calcium imaging techniques, we found that a novel CaMKK/AMPK pathway could be involved in the intracellular regulation of DUM neuron nAChRs. The CaMKK selective inhibitor, STO, reduced nicotinic current amplitudes, and strongly when co-applied with α-Bgt. Interestingly, intracellular application of the AMPK activator, A-76, prevented the reduction in nicotine-induced currents observed in the presence of the AMPK inhibitor, dorsomorphin. STO prevented the increase in intracellular calcium induced by nicotine, which was not dependent on α-Bgt. Currents induced by 1 mM LMA, a selective activator of nAChR2, were reduced under bath application of STO, and mecamylamine, which blocked nAChR2 subtype, inhibited the increase in intracellular calcium induced by LMA. These findings provide insight into potential complex mechanisms linked to the modulation of the DUM neuron nAChRs and CaMKK pathway.
Collapse
Affiliation(s)
- Maria Taha
- Laboratoire Physiologie, Ecologie et Environnement (P2E), USC-INRAE 1328, Université d'Orléans, Orléans, France
| | - Jean-Noël Houchat
- Laboratoire Physiologie, Ecologie et Environnement (P2E), USC-INRAE 1328, Université d'Orléans, Orléans, France
| | - Emiliane Taillebois
- Laboratoire Physiologie, Ecologie et Environnement (P2E), USC-INRAE 1328, Université d'Orléans, Orléans, France
| | - Steeve H Thany
- Laboratoire Physiologie, Ecologie et Environnement (P2E), USC-INRAE 1328, Université d'Orléans, Orléans, France
| |
Collapse
|
11
|
Kakoti BB, Alom S, Deka K, Halder RK. AMPK pathway: an emerging target to control diabetes mellitus and its related complications. J Diabetes Metab Disord 2024; 23:441-459. [PMID: 38932895 PMCID: PMC11196491 DOI: 10.1007/s40200-024-01420-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 03/07/2024] [Indexed: 06/28/2024]
Abstract
Purpose In this extensive review work, the important role of AMP-activated protein kinase (AMPK) in causing of diabetes mellitus has been highlighted. Structural feature of AMPK as well its regulations and roles are described nicely, and the association of AMPK with the diabetic complications like nephropathy, neuropathy and retinopathy are also explained along with the connection between AMPK and β-cell function, insulin resistivity, mTOR, protein metabolism, autophagy and mitophagy and effect on protein and lipid metabolism. Methods Published journals were searched on the database like PubMed, Medline, Scopus and Web of Science by using keywords such as AMPK, diabetes mellitus, regulation of AMPK, complications of diabetes mellitus, autophagy, apoptosis etc. Result After extensive review, it has been found that, kinase enzyme like AMPK is having vital role in management of type II diabetes mellitus. AMPK involve in enhance the concentration of glucose transporter like GLUT 1 and GLUT 4 which result in lowering of blood glucose level in influx of blood glucose into the cells; AMPK increases the insulin sensitivity and decreases the insulin resistance and further AMPK decreases the apoptosis of β-cells which result into secretion of insulin and AMPK is also involve in declining of oxidative stress, lipotoxicity and inflammation, owing to which organ damage due to diabetes mellitus can be lowered by activation of AMPK. Conclusion As AMPK activation leads to overall control of diabetes mellitus, designing and developing of small molecules or peptide that can act as AMPK agonist will be highly beneficial for control or manage diabetes mellitus.
Collapse
Affiliation(s)
- Bibhuti B. Kakoti
- Department of Pharmaceutical Sciences, Dibrugarh University, 786004 Dibrugarh, Assam India
| | - Shahnaz Alom
- Department of Pharmaceutical Sciences, Dibrugarh University, 786004 Dibrugarh, Assam India
- Department of Pharmacology, Girijananda Chowdhury Institute of Pharmaceutical Sciences, Girijananda Chowdhury University- Tezpur campus, 784501 Sonitpur, Assam India
| | - Kangkan Deka
- Department of Pharmaceutical Sciences, Dibrugarh University, 786004 Dibrugarh, Assam India
- Department of Pharmacognosy, NETES Institute of Pharmaceutical Science, NEMCARE Group of Institutions, 781125 Mirza, Kamrup, Assam India
| | - Raj Kumar Halder
- Ruhvenile Biomedical, Plot -8 OCF Pocket Institution, Sarita Vihar, 110076 Delhi, India
| |
Collapse
|
12
|
Liu D, Wang T, Zhao X, Chen J, Yang T, Shen Y, Zhou YD. Saturated fatty acids stimulate cytokine production in tanycytes via the PP2Ac-dependent signaling pathway. J Cereb Blood Flow Metab 2024; 44:985-999. [PMID: 38069840 PMCID: PMC11318396 DOI: 10.1177/0271678x231219115] [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] [Received: 06/16/2023] [Revised: 09/18/2023] [Accepted: 11/10/2023] [Indexed: 05/18/2024]
Abstract
The hypothalamic tanycytes are crucial for free fatty acids (FFAs) detection, storage, and transport within the central nervous system. They have been shown to effectively respond to fluctuations in circulating FFAs, thereby regulating energy homeostasis. However, the precise molecular mechanisms by which tanycytes modulate lipid utilization remain unclear. Here, we report that the catalytic subunit of protein phosphatase 2 A (PP2Ac), a serine/threonine phosphatase, is expressed in tanycytes and its accumulation and activation occur in response to high-fat diet consumption. In vitro, tanycytic PP2Ac responds to palmitic acid (PA) exposure and accumulates and is activated at an early stage in an AMPK-dependent manner. Furthermore, activated PP2Ac boosts hypoxia-inducible factor-1α (HIF-1α) accumulation, resulting in upregulation of an array of cytokines. Pretreatment with a PP2Ac inhibitor, LB100, prevented the PA-induced elevation of vascular endothelial growth factor (VEGF), fibroblast growth factor 1 (FGF1), hepatocyte growth factor (HGF), and dipeptidyl peptidase IV (DPPIV or CD26). Our results disclose a mechanism of lipid metabolism in tanycytes that involves the activation of PP2Ac and highlight the physiological significance of PP2Ac in hypothalamic tanycytes in response to overnutrition and efficacious treatment of obesity.
Collapse
Affiliation(s)
- Danyang Liu
- Institute of Neuroscience, NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Brain Science and Brain Medicine, Hangzhou, China
- Nanhu Brain-computer Interface Institute, Hangzhou 311100, China
- Department of Ophthalmology of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, Hangzhou, China
| | - Tao Wang
- Institute of Neuroscience, NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Brain Science and Brain Medicine, Hangzhou, China
| | - Xingqi Zhao
- Institute of Neuroscience, NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Brain Science and Brain Medicine, Hangzhou, China
| | - Juan Chen
- School of Mental Health, Bengbu Medical College, Bengbu, Anhui, China
| | - Tianqi Yang
- Institute of Neuroscience, NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Brain Science and Brain Medicine, Hangzhou, China
| | - Yi Shen
- Institute of Neuroscience, NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Brain Science and Brain Medicine, Hangzhou, China
- Department of Neurobiology and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yu-Dong Zhou
- Institute of Neuroscience, NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Brain Science and Brain Medicine, Hangzhou, China
- Lingang Laboratory, Shanghai 200031, China
- Department of Ophthalmology of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, Hangzhou, China
| |
Collapse
|
13
|
Zhou Y, Zhang X, Baker JS, Davison GW, Yan X. Redox signaling and skeletal muscle adaptation during aerobic exercise. iScience 2024; 27:109643. [PMID: 38650987 PMCID: PMC11033207 DOI: 10.1016/j.isci.2024.109643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
Redox regulation is a fundamental physiological phenomenon related to oxygen-dependent metabolism, and skeletal muscle is mainly regarded as a primary site for oxidative phosphorylation. Several studies have revealed the importance of reactive oxygen and nitrogen species (RONS) in the signaling process relating to muscle adaptation during exercise. To date, improving knowledge of redox signaling in modulating exercise adaptation has been the subject of comprehensive work and scientific inquiry. The primary aim of this review is to elucidate the molecular and biochemical pathways aligned to RONS as activators of skeletal muscle adaptation and to further identify the interconnecting mechanisms controlling redox balance. We also discuss the RONS-mediated pathways during the muscle adaptive process, including mitochondrial biogenesis, muscle remodeling, vascular angiogenesis, neuron regeneration, and the role of exogenous antioxidants.
Collapse
Affiliation(s)
- Yingsong Zhou
- Faculty of Sports Science, Ningbo University, Ningbo, China
| | - Xuan Zhang
- School of Wealth Management, Ningbo University of Finance and Economics, Ningbo, China
| | - Julien S. Baker
- Centre for Health and Exercise Science Research, Hong Kong Baptist University, Kowloon Tong 999077, Hong Kong
| | - Gareth W. Davison
- Sport and Exercise Sciences Research Institute, Ulster University, Belfast BT15 IED, UK
| | - Xiaojun Yan
- School of Marine Sciences, Ningbo University, Ningbo, China
| |
Collapse
|
14
|
Yang C, Rubin L, Yu X, Lazarovici P, Zheng W. Preclinical evidence using synthetic compounds and natural products indicates that AMPK represents a potential pharmacological target for the therapy of pulmonary diseases. Med Res Rev 2024; 44:1326-1369. [PMID: 38229486 DOI: 10.1002/med.22014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 12/07/2023] [Accepted: 12/30/2023] [Indexed: 01/18/2024]
Abstract
Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) is a highly conserved eukaryotic enzyme discovered as a key regulator of cellular energy homeostasis, with anti-inflammation, antioxidative stress, anticancer, and antifibrosis beneficial effects. AMPK is dysregulated in human pulmonary diseases such as acute lung injury, nonsmall cell lung cancer, pulmonary fibrosis, chronic obstructive pulmonary disease, and asthma. This review provides an overview of the beneficial role of natural, synthetic, and Chinese traditional medicines AMPK modulators in pulmonary diseases, and highlights the role of the AMPK signaling pathway in the lung, emphasizing the importance of finding lead compounds and drugs that can target and modulate AMPK to treat the lung diseases.
Collapse
Affiliation(s)
- Chao Yang
- Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Limor Rubin
- Allergy and Clinical Immunology Unit, Department of Medicine, Jerusalem, Israel
| | - Xiyong Yu
- School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Philip Lazarovici
- School of Pharmacy Institute for Drug Research, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Wenhua Zheng
- Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| |
Collapse
|
15
|
Hawley SA, Russell FM, Hardie DG. AMP-activated protein kinase can be allosterically activated by ADP but AMP remains the key activating ligand. Biochem J 2024; 481:587-599. [PMID: 38592738 PMCID: PMC11088877 DOI: 10.1042/bcj20240082] [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: 04/02/2024] [Accepted: 04/09/2024] [Indexed: 04/10/2024]
Abstract
The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status. When activated by increases in ADP:ATP and/or AMP:ATP ratios (signalling energy deficit), AMPK acts to restore energy balance. Binding of AMP to one or more of three CBS repeats (CBS1, CBS3, CBS4) on the AMPK-γ subunit activates the kinase complex by three complementary mechanisms: (i) promoting α-subunit Thr172 phosphorylation by the upstream kinase LKB1; (ii) protecting against Thr172 dephosphorylation; (iii) allosteric activation. Surprisingly, binding of ADP has been reported to mimic the first two effects, but not the third. We now show that at physiologically relevant concentrations of Mg.ATP2- (above those used in the standard assay) ADP binding does cause allosteric activation. However, ADP causes only a modest activation because (unlike AMP), at concentrations just above those where activation becomes evident, ADP starts to cause competitive inhibition at the catalytic site. Our results cast doubt on the physiological relevance of the effects of ADP and suggest that AMP is the primary activator in vivo. We have also made mutations to hydrophobic residues involved in binding adenine nucleotides at each of the three γ subunit CBS repeats of the human α2β2γ1 complex and examined their effects on regulation by AMP and ADP. Mutation of the CBS3 site has the largest effects on all three mechanisms of AMP activation, especially at lower ATP concentrations, while mutation of CBS4 reduces the sensitivity to AMP. All three sites appear to be required for allosteric activation by ADP.
Collapse
Affiliation(s)
- Simon A. Hawley
- Division of Cell Signalling and Immunology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
| | - Fiona M. Russell
- Division of Cell Signalling and Immunology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
| | - D. Grahame Hardie
- Division of Cell Signalling and Immunology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
| |
Collapse
|
16
|
van den Biggelaar RHGA, Walburg KV, van den Eeden SJF, van Doorn CLR, Meiler E, de Ries AS, Meijer AH, Ottenhoff THM, Saris A. Identification of kinase modulators as host-directed therapeutics against intracellular methicillin-resistant Staphylococcus aureus. Front Cell Infect Microbiol 2024; 14:1367938. [PMID: 38590439 PMCID: PMC10999543 DOI: 10.3389/fcimb.2024.1367938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 03/11/2024] [Indexed: 04/10/2024] Open
Abstract
The increasing prevalence of antimicrobial-resistant Staphylococcus aureus strains, especially methicillin-resistant S. aureus (MRSA), poses a threat to successful antibiotic treatment. Unsuccessful attempts to develop a vaccine and rising resistance to last-resort antibiotics urge the need for alternative treatments. Host-directed therapy (HDT) targeting critical intracellular stages of S. aureus emerges as a promising alternative, potentially acting synergistically with antibiotics and reducing the risk of de novo drug resistance. We assessed 201 ATP-competitive kinase inhibitors from Published Kinase Inhibitor Sets (PKIS1 and PKIS2) against intracellular MRSA. Seventeen hit compounds were identified, of which the two most effective and well-tolerated hit compounds (i.e., GW633459A and GW296115X) were selected for further analysis. The compounds did not affect planktonic bacterial cultures, while they were active in a range of human cell lines of cervical, skin, lung, breast and monocyte origin, confirming their host-directed mechanisms. GW633459A, structurally related to lapatinib, exhibited an HDT effect on intracellular MRSA independently of its known human epidermal growth factor receptor (EGFR)/(HER) kinase family targets. GW296115X activated adenosine monophosphate-activated protein kinase (AMPK), thereby enhancing bacterial degradation via autophagy. Finally, GW296115X not only reduced MRSA growth in human cells but also improved the survival rates of MRSA-infected zebrafish embryos, highlighting its potential as HDT.
Collapse
Affiliation(s)
- Robin H. G. A. van den Biggelaar
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | - Kimberley V. Walburg
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Susan J. F. van den Eeden
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Cassandra L. R. van Doorn
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Eugenia Meiler
- Global Health Medicines R&D, GlaxoSmithKline, Tres Cantos, Spain
| | - Alex S. de Ries
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | | | - Tom H. M. Ottenhoff
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Anno Saris
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| |
Collapse
|
17
|
Zhang X, Zhao Y, Guo D, Luo M, Zhang Q, Zhang L, Zhang D. Exercise Improves Heart Function after Myocardial Infarction: The Merits of AMPK. Cardiovasc Drugs Ther 2024:10.1007/s10557-024-07564-2. [PMID: 38436878 DOI: 10.1007/s10557-024-07564-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/20/2024] [Indexed: 03/05/2024]
Abstract
BACKGROUND AMPK is considered an important protein signaling pathway that has been shown to exert prominent cardioprotective effects on the pathophysiological mechanisms of numerous diseases. Following myocardial infarction, severe impairment of cardiac function occurs, leading to complications such as heart failure and arrhythmia. Therefore, protecting the heart and improving cardiac function are important therapeutic goals after myocardial infarction. Currently, there is substantial ongoing research on exercise-centered rehabilitation training, positioning exercise training as a significant nonpharmacological approach for preventing and treating numerous cardiovascular diseases. OBJECTIVE Previous studies have reported that exercise can activate AMPK phosphorylation and upregulate the AMPK signaling pathway to play a cardioprotective role in coronary artery disease, but the specific mechanism involved remains to be elucidated. CONCLUSION This review discusses the role and mechanism of the exercise-mediated AMPK pathway in improving postinfarction cardiac function through existing studies and describes the mechanism of exercise-induced myocardial repair of AMPK from multiple perspectives to formulate a reasonable and optimal exercise rehabilitation program for the prevention and treatment of myocardial infarction patients in the clinic.
Collapse
Affiliation(s)
- Xiaodi Zhang
- Department of Cardiovascular Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China
| | - Yi Zhao
- Department of Cardiovascular Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China
| | - Dafen Guo
- Outpatient Department Office, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China
| | - Mingxian Luo
- Department of Cardiovascular Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China
| | - Qing Zhang
- Department of Cardiovascular Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China
| | - Li Zhang
- Discipline Inspection and Supervision Office of Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China.
| | - Dengshen Zhang
- Department of Cardiovascular Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, China.
| |
Collapse
|
18
|
Qi Y, Zhang YM, Gao YN, Chen WG, Zhou T, Chang L, Zang Y, Li J. AMPK role in epilepsy: a promising therapeutic target? J Neurol 2024; 271:748-771. [PMID: 38010498 DOI: 10.1007/s00415-023-12062-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 11/29/2023]
Abstract
Epilepsy is a complex and multifaceted neurological disorder characterized by spontaneous and recurring seizures. It poses significant therapeutic challenges due to its diverse etiology and often-refractory nature. This comprehensive review highlights the pivotal role of AMP-activated protein kinase (AMPK), a key metabolic regulator involved in cellular energy homeostasis, which may be a promising therapeutic target for epilepsy. Current therapeutic strategies such as antiseizure medication (ASMs) can alleviate seizures (up to 70%). However, 30% of epileptic patients may develop refractory epilepsy. Due to the complicated nature of refractory epilepsy, other treatment options such as ketogenic dieting, adjunctive therapy, and in limited cases, surgical interventions are employed. These therapy options are only suitable for a select group of patients and have limitations of their own. Current treatment options for epilepsy need to be improved. Emerging evidence underscores a potential association between impaired AMPK functionality in the brain and the onset of epilepsy, prompting an in-depth examination of AMPK's influence on neural excitability and ion channel regulation, both critical factors implicated in epileptic seizures. AMPK activation through agents such as metformin has shown promising antiepileptic effects in various preclinical and clinical settings. These effects are primarily mediated through the inhibition of the mTOR signaling pathway, activation of the AMPK-PI3K-c-Jun pathway, and stimulation of the PGC-1α pathway. Despite the potential of AMPK-targeted therapies, several aspects warrant further exploration, including the detailed mechanisms of AMPK's role in different brain regions, the impact of AMPK under various conditional circumstances such as neural injury and zinc toxicity, the long-term safety and efficacy of chronic metformin use in epilepsy treatment, and the potential benefits of combination therapy involving AMPK activators. Moreover, the efficacy of AMPK activators in refractory epilepsy remains an open question. This review sets the stage for further research with the aim of enhancing our understanding of the role of AMPK in epilepsy, potentially leading to the development of more effective, AMPK-targeted therapeutic strategies for this challenging and debilitating disorder.
Collapse
Affiliation(s)
- Yingbei Qi
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, Zhejiang, China
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yong-Mei Zhang
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, Zhejiang, China
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ya-Nan Gao
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Wen-Gang Chen
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Ting Zhou
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Liuliu Chang
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yi Zang
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
| | - Jia Li
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, Zhejiang, China.
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
19
|
Lee H, Yoon H. Mitochondrial sirtuins: Energy dynamics and cancer metabolism. Mol Cells 2024; 47:100029. [PMID: 38331199 PMCID: PMC10960136 DOI: 10.1016/j.mocell.2024.100029] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/18/2024] [Accepted: 01/31/2024] [Indexed: 02/10/2024] Open
Abstract
Mitochondria are pivotal for energy regulation and are linked to cancer. Mitochondrial sirtuins, (Sirtuin) SIRT3, SIRT4, and SIRT5, play crucial roles in cancer metabolism. This review explores their impact on cellular processes, with a focus on the NAD+ interplay and the modulation of their enzymatic activities. The varied roles of SIRT3, SIRT4, and SIRT5 in metabolic adaptation and cancer are outlined, emphasizing their tumor suppressor or oncogenic nature. We propose new insights into sirtuin biology, and cancer therapeutics, suggesting an integrated proteomics and metabolomics approach for a comprehensive understanding of mitochondrial sirtuins in cancer.
Collapse
Affiliation(s)
- Hojun Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Haejin Yoon
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
| |
Collapse
|
20
|
Skalka GL, Tsakovska M, Murphy DJ. Kinase signalling adaptation supports dysfunctional mitochondria in disease. Front Mol Biosci 2024; 11:1354682. [PMID: 38434478 PMCID: PMC10906720 DOI: 10.3389/fmolb.2024.1354682] [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: 12/12/2023] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
Mitochondria form a critical control nexus which are essential for maintaining correct tissue homeostasis. An increasing number of studies have identified dysregulation of mitochondria as a driver in cancer. However, which pathways support and promote this adapted mitochondrial function? A key hallmark of cancer is perturbation of kinase signalling pathways. These pathways include mitogen activated protein kinases (MAPK), lipid secondary messenger networks, cyclic-AMP-activated (cAMP)/AMP-activated kinases (AMPK), and Ca2+/calmodulin-dependent protein kinase (CaMK) networks. These signalling pathways have multiple substrates which support initiation and persistence of cancer. Many of these are involved in the regulation of mitochondrial morphology, mitochondrial apoptosis, mitochondrial calcium homeostasis, mitochondrial associated membranes (MAMs), and retrograde ROS signalling. This review will aim to both explore how kinase signalling integrates with these critical mitochondrial pathways and highlight how these systems can be usurped to support the development of disease. In addition, we will identify areas which require further investigation to fully understand the complexities of these regulatory interactions. Overall, this review will emphasize how studying the interaction between kinase signalling and mitochondria improves our understanding of mitochondrial homeostasis and can yield novel therapeutic targets to treat disease.
Collapse
Affiliation(s)
- George L. Skalka
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Mina Tsakovska
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Daniel J. Murphy
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
- CRUK Scotland Institute, Glasgow, United Kingdom
| |
Collapse
|
21
|
Kobayashi K, Mochizuki J, Yamazaki F, Sashihara T. Yogurt starter strains ameliorate intestinal barrier dysfunction via activating AMPK in Caco-2 cells. Tissue Barriers 2024; 12:2184157. [PMID: 36852963 PMCID: PMC10832913 DOI: 10.1080/21688370.2023.2184157] [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: 09/27/2022] [Accepted: 02/19/2023] [Indexed: 03/01/2023] Open
Abstract
Lactic acid bacteria (LAB) are commonly used probiotics that improve human health in various aspects. We previously reported that yogurt starter strains, Lactobacillus delbrueckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131, potentially enhance the intestinal epithelial barrier function by inducing the expression of antimicrobial peptides in the small intestine. However, their effects on physical barrier functions remain unknown. In this study, we found that both strains ameliorated the decreased trans-epithelial resistance and the increased permeability of fluorescein isothiocyanate-dextran induced by tumor necrosis factor (TNF)-α and interferon (IFN)-γ in Caco-2 cells. We also demonstrated that LAB prevented a decrease in the expression and disassembly of tight junctions (TJs) induced by TNF-α and IFN-γ. To assess the repair activity of TJs, a calcium switch assay was performed. Both strains were found to promote the reassembly of TJs, and their activity was canceled by the inhibitor of AMP-activated protein kinase (AMPK). Moreover, these strains showed increased AMPK phosphorylation. These observations suggest that the strains ameliorated physical barrier dysfunction via the activation of AMPK. The activities preventing barrier destruction induced by TNF-α and IFN-γ were strain-dependent. Several strains containing L. bulgaricus 2038 and S. thermophilus 1131 significantly suppressed the barrier impairment, and L. bulgaricus 2038 showed the strongest activity among them. Our findings suggest that the intake of L. bulgaricus 2038 and S. thermophilus 1131 is a potential strategy for the prevention and repair of leaky gut.
Collapse
Affiliation(s)
- Kyosuke Kobayashi
- Food Microbiology and Function Research Laboratories, R&D Division, Meiji Co., Ltd, Tokyo, Japan
| | - Junko Mochizuki
- Food Microbiology and Function Research Laboratories, R&D Division, Meiji Co., Ltd, Tokyo, Japan
| | - Fuka Yamazaki
- Food Microbiology and Function Research Laboratories, R&D Division, Meiji Co., Ltd, Tokyo, Japan
| | - Toshihiro Sashihara
- Food Microbiology and Function Research Laboratories, R&D Division, Meiji Co., Ltd, Tokyo, Japan
| |
Collapse
|
22
|
Rahman AA, Butcko AJ, Songyekutu E, Granneman JG, Mottillo EP. Direct effects of adipocyte lipolysis on AMPK through intracellular long-chain acyl-CoA signaling. Sci Rep 2024; 14:19. [PMID: 38167670 PMCID: PMC10761689 DOI: 10.1038/s41598-023-50903-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 12/27/2023] [Indexed: 01/05/2024] Open
Abstract
Long-chain acyl-CoAs (LC-acyl-CoAs) are important intermediary metabolites and are also thought to function as intracellular signaling molecules; however, the direct effects of LC-acyl-CoAs have been difficult to determine in real-time and dissociate from Protein Kinase A (PKA) signaling. Here, we examined the direct role of lipolysis in generating intracellular LC-acyl-CoAs and activating AMPK in white adipocytes by pharmacological activation of ABHD5 (also known as CGI-58), a lipase co-activator. Activation of lipolysis in 3T3-L1 adipocytes independent of PKA with synthetic ABHD5 ligands, resulted in greater activation of AMPK compared to receptor-mediated activation with isoproterenol, a β-adrenergic receptor agonist. Importantly, the effect of pharmacological activation of ABHD5 on AMPK activation was blocked by inhibiting ATGL, the rate-limiting enzyme for triacylglycerol hydrolysis. Utilizing a novel FRET sensor to detect intracellular LC-acyl-CoAs, we demonstrate that stimulation of lipolysis in 3T3-L1 adipocytes increased the production of LC-acyl-CoAs, an effect which was blocked by inhibition of ATGL. Moreover, ATGL inhibition blocked AMPKβ1 S108 phosphorylation, a site required for allosteric regulation. Increasing intracellular LC-acyl-CoAs by removal of BSA in the media and pharmacological inhibition of DGAT1 and 2 resulted in greater activation of AMPK. Finally, inhibiting LC-acyl-CoA generation reduced activation of AMPK; however, did not lower energy charge. Overall, results demonstrate that lipolysis in white adipocytes directly results in allosteric activation of AMPK through the generation of LC-acyl-CoAs.
Collapse
Affiliation(s)
- Abir A Rahman
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, 6135 Woodward Ave., Detroit, MI, 48202, USA
| | - Andrew J Butcko
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, 6135 Woodward Ave., Detroit, MI, 48202, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48202, USA
| | - Emmanuel Songyekutu
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48202, USA
| | - James G Granneman
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, 48202, USA
| | - Emilio P Mottillo
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, 6135 Woodward Ave., Detroit, MI, 48202, USA.
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48202, USA.
| |
Collapse
|
23
|
Shao J, Lang Y, Ding M, Yin X, Cui L. Transcription Factor EB: A Promising Therapeutic Target for Ischemic Stroke. Curr Neuropharmacol 2024; 22:170-190. [PMID: 37491856 PMCID: PMC10788889 DOI: 10.2174/1570159x21666230724095558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 07/27/2023] Open
Abstract
Transcription factor EB (TFEB) is an important endogenous defensive protein that responds to ischemic stimuli. Acute ischemic stroke is a growing concern due to its high morbidity and mortality. Most survivors suffer from disabilities such as numbness or weakness in an arm or leg, facial droop, difficulty speaking or understanding speech, confusion, impaired balance or coordination, or loss of vision. Although TFEB plays a neuroprotective role, its potential effect on ischemic stroke remains unclear. This article describes the basic structure, regulation of transcriptional activity, and biological roles of TFEB relevant to ischemic stroke. Additionally, we explore the effects of TFEB on the various pathological processes underlying ischemic stroke and current therapeutic approaches. The information compiled here may inform clinical and basic studies on TFEB, which may be an effective therapeutic drug target for ischemic stroke.
Collapse
Affiliation(s)
- Jie Shao
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Yue Lang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Manqiu Ding
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Xiang Yin
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Li Cui
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Jilin University, Changchun, China
| |
Collapse
|
24
|
Yuan Y, Wang F, Liu X, Shuai B, Fan H. The Role of AMPK Signaling in Ulcerative Colitis. Drug Des Devel Ther 2023; 17:3855-3875. [PMID: 38170149 PMCID: PMC10759424 DOI: 10.2147/dddt.s442154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024] Open
Abstract
Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease characterized by inflammation and ulcer formation of the intestinal mucosa. Due to its high recurrence rate, prolonged course, limited curative options, and significant impact on patients' quality of life, along with a notable potential for malignant transformation, UC is designated as a refractory global health challenge by the World Health Organization (WHO). The elucidation of the pathogenesis and therapeutic strategies for UC requires further in-depth investigation. AMP-activated protein kinase (AMPK) serves as a central regulator of cellular energy metabolic homeostasis. Emerging evidence indicates that interventions involving traditional Chinese medicine (TCM) components, as well as other pharmacological measures, exert beneficial effects on the intestinal mucosal inflammation and epithelial barrier dysfunction in UC by modulating AMPK signaling, thereby influencing biological processes such as cellular autophagy, apoptosis, inflammatory responses, macrophage polarization, and NLRP3 inflammasome-mediated pyroptosis. The role of AMPK in UC is of significant importance. This manuscript provides a comprehensive overview of the mechanisms through which AMPK is involved in UC, as well as a compilation of pharmacological agents capable of activating the AMPK signaling pathway within the context of UC. The primary objective is to facilitate a deeper comprehension of the pivotal role of AMPK in UC among researchers and clinical practitioners, thereby advancing the identification of novel therapeutic targets for interventions in UC.
Collapse
Affiliation(s)
- Yuyi Yuan
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| | - Fang Wang
- Department of Rehabilitation Medicine, Jingshan Union Hospital, Union Hospital, Huazhong University of Science and Technology, Jingshan, Hubei, 431800, People’s Republic of China
| | - Xingxing Liu
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| | - Bo Shuai
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| | - Heng Fan
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| |
Collapse
|
25
|
Ross FA, Hawley SA, Russell FM, Goodman N, Hardie DG. Frequent loss-of-function mutations in the AMPK-α2 catalytic subunit suggest a tumour suppressor role in human skin cancers. Biochem J 2023; 480:1951-1968. [PMID: 37962491 PMCID: PMC10754287 DOI: 10.1042/bcj20230380] [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: 09/07/2023] [Revised: 11/07/2023] [Accepted: 11/13/2023] [Indexed: 11/15/2023]
Abstract
The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status activated by increases in AMP or ADP relative to ATP. Once activated, it phosphorylates targets that promote ATP-generating catabolic pathways or inhibit ATP-consuming anabolic pathways, helping to restore cellular energy balance. Analysis of human cancer genome studies reveals that the PRKAA2 gene (encoding the α2 isoform of the catalytic subunit) is often subject to mis-sense mutations in cancer, particularly in melanoma and non-melanoma skin cancers, where up to 70 mis-sense mutations have been documented, often accompanied by loss of the tumour suppressor NF1. Recently it has been reported that knockout of PRKAA2 in NF1-deficient melanoma cells promoted anchorage-independent growth in vitro, as well as growth as xenografts in immunodeficient mice in vivo, suggesting that AMPK-α2 can act as a tumour suppressor in that context. However, very few of the mis-sense mutations in PRKAA2 that occur in human skin cancer and melanoma have been tested to see whether they cause loss-of-function. We have addressed this by making most of the reported mutations and testing their activity when expressed in AMPK knockout cells. Of 55 different mis-sense mutations (representing 75 cases), 9 (12%) appeared to cause a total loss of activity, 18 (24%) a partial loss, 11 (15%) an increase in phenformin-stimulated kinase activity, while just 37 (49%) had no clear effect on kinase activity. This supports the idea that AMPK-α2 acts as a tumour suppressor in the context of human skin cancer.
Collapse
Affiliation(s)
- Fiona A. Ross
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Scotland, U.K
| | - Simon A. Hawley
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Scotland, U.K
| | - Fiona M. Russell
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Scotland, U.K
| | - Nicola Goodman
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Scotland, U.K
| | - D. Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Scotland, U.K
| |
Collapse
|
26
|
Chen YT, Nyam TTE, Tsai LC, Chang CH, Su CL, Ho CH, Chio CC, Gean PW, Kuo JR. Pretreatment with Lovastatin Improves Depression-Like Behavior After Traumatic Brain Injury Through Activation of the AMPK Pathway. World Neurosurg 2023; 180:e350-e363. [PMID: 37757945 DOI: 10.1016/j.wneu.2023.09.071] [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: 06/02/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023]
Abstract
BACKGROUND The beneficial effect of pretreatment with statins on traumatic brain injury (TBI)-induced depression and anxiety and its mechanism of action remain unclear. In this study, we combined epidemiological and experimental animal data to clarify this issue. METHODS We used the Taiwan National Health Insurance database to identify patients who were diagnosed with TBI from 2000 to 2013 and compared patients with and without statin treatment matched by age, sex, and underlying comorbidities in a 1:1 ratio. The risk of developing depression and/or anxiety was compared between patients with and without a statin using Cox proportional hazards regression. We also used a rat model to assess the effect of lovastatin pretreatment on neurobehavioral and neuropathological changes following TBI. RESULTS The risk of developing depression was lower in the 41,803 patients in the statin cohort than nonstatin cohort (adjusted hazard ratio, 0.91 [95% confidence interval, 0.83-0.99]). In animal models, the lovastatin group had significantly reduced infarct volume, decreased immobility time and latency to eat, a reduced number of Fluoro- Jade-positive cells and levels of glial fibrillary acidic protein and tumor necrosis factor-alpha, and increased adenosine monophosphate -activated protein kinase (AMPK) and its upstream kinase liver kinase B1 in the hippocampal dentate gyrus. These effects were blocked in AMPK inhibitor-pretreated TBI rats. CONCLUSIONS Our epidemiological data showed that a decreased risk of depression was associated with statin pretreatment, which was supported by an animal study. The underlying mechanism for this appears to involve AMPK activation in the statin pretreatment-induced alleviation of TBI.
Collapse
Affiliation(s)
- Yu-Ting Chen
- Department of Neurosurgery, Chi Mei Medical Center, Tainan, Taiwan
| | | | - Li-Chen Tsai
- Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Chih-Hua Chang
- Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Chun-Lin Su
- Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Chung-Han Ho
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan; Department of Information Management, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Chung-Ching Chio
- Department of Neurosurgery, Chi Mei Medical Center, Tainan, Taiwan
| | - Po-Wu Gean
- Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
| | - Jinn-Rung Kuo
- Department of Neurosurgery, Chi Mei Medical Center, Tainan, Taiwan; Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan; Department of Post-Baccalaureate Medicine, National Sun Yat-sen University, Kaohsiung, Taiwan.
| |
Collapse
|
27
|
Townsend LK, Steinberg GR. AMPK and the Endocrine Control of Metabolism. Endocr Rev 2023; 44:910-933. [PMID: 37115289 DOI: 10.1210/endrev/bnad012] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/10/2023] [Accepted: 04/24/2023] [Indexed: 04/29/2023]
Abstract
Complex multicellular organisms require a coordinated response from multiple tissues to maintain whole-body homeostasis in the face of energetic stressors such as fasting, cold, and exercise. It is also essential that energy is stored efficiently with feeding and the chronic nutrient surplus that occurs with obesity. Mammals have adapted several endocrine signals that regulate metabolism in response to changes in nutrient availability and energy demand. These include hormones altered by fasting and refeeding including insulin, glucagon, glucagon-like peptide-1, catecholamines, ghrelin, and fibroblast growth factor 21; adipokines such as leptin and adiponectin; cell stress-induced cytokines like tumor necrosis factor alpha and growth differentiating factor 15, and lastly exerkines such as interleukin-6 and irisin. Over the last 2 decades, it has become apparent that many of these endocrine factors control metabolism by regulating the activity of the AMPK (adenosine monophosphate-activated protein kinase). AMPK is a master regulator of nutrient homeostasis, phosphorylating over 100 distinct substrates that are critical for controlling autophagy, carbohydrate, fatty acid, cholesterol, and protein metabolism. In this review, we discuss how AMPK integrates endocrine signals to maintain energy balance in response to diverse homeostatic challenges. We also present some considerations with respect to experimental design which should enhance reproducibility and the fidelity of the conclusions.
Collapse
Affiliation(s)
- Logan K Townsend
- Centre for Metabolism Obesity and Diabetes Research, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Gregory R Steinberg
- Centre for Metabolism Obesity and Diabetes Research, Hamilton, ON L8S 4L8, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4L8, Canada
| |
Collapse
|
28
|
McLelland GL, Lopez-Osias M, Verzijl CRC, Ellenbroek BD, Oliveira RA, Boon NJ, Dekker M, van den Hengel LG, Ali R, Janssen H, Song JY, Krimpenfort P, van Zutphen T, Jonker JW, Brummelkamp TR. Identification of an alternative triglyceride biosynthesis pathway. Nature 2023; 621:171-178. [PMID: 37648867 PMCID: PMC10482677 DOI: 10.1038/s41586-023-06497-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 07/28/2023] [Indexed: 09/01/2023]
Abstract
Triacylglycerols (TAGs) are the main source of stored energy in the body, providing an important substrate pool for mitochondrial beta-oxidation. Imbalances in the amount of TAGs are associated with obesity, cardiac disease and various other pathologies1,2. In humans, TAGs are synthesized from excess, coenzyme A-conjugated fatty acids by diacylglycerol O-acyltransferases (DGAT1 and DGAT2)3. In other organisms, this activity is complemented by additional enzymes4, but whether such alternative pathways exist in humans remains unknown. Here we disrupt the DGAT pathway in haploid human cells and use iterative genetics to reveal an unrelated TAG-synthesizing system composed of a protein we called DIESL (also known as TMEM68, an acyltransferase of previously unknown function) and its regulator TMX1. Mechanistically, TMX1 binds to and controls DIESL at the endoplasmic reticulum, and loss of TMX1 leads to the unconstrained formation of DIESL-dependent lipid droplets. DIESL is an autonomous TAG synthase, and expression of human DIESL in Escherichia coli endows this organism with the ability to synthesize TAG. Although both DIESL and the DGATs function as diacylglycerol acyltransferases, they contribute to the cellular TAG pool under specific conditions. Functionally, DIESL synthesizes TAG at the expense of membrane phospholipids and maintains mitochondrial function during periods of extracellular lipid starvation. In mice, DIESL deficiency impedes rapid postnatal growth and affects energy homeostasis during changes in nutrient availability. We have therefore identified an alternative TAG biosynthetic pathway driven by DIESL under potent control by TMX1.
Collapse
Affiliation(s)
- Gian-Luca McLelland
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
| | - Marta Lopez-Osias
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Cristy R C Verzijl
- Department of Pediatrics, Section of Molecular Metabolism and Nutrition, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Brecht D Ellenbroek
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Rafaela A Oliveira
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Nicolaas J Boon
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Marleen Dekker
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Lisa G van den Hengel
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Rahmen Ali
- Animal Modeling Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Hans Janssen
- Electron Microscope Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Ji-Ying Song
- Animal Pathology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Paul Krimpenfort
- Animal Modeling Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Tim van Zutphen
- Department of Pediatrics, Section of Molecular Metabolism and Nutrition, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Faculty Campus Fryslân, University of Groningen, Leeuwarden, The Netherlands
| | - Johan W Jonker
- Department of Pediatrics, Section of Molecular Metabolism and Nutrition, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Thijn R Brummelkamp
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
| |
Collapse
|
29
|
Negoita F, Addinsall AB, Hellberg K, Bringas CF, Hafen PS, Sermersheim TJ, Agerholm M, Lewis CTA, Ahwazi D, Ling NXY, Larsen JK, Deshmukh AS, Hossain MA, Oakhill JS, Ochala J, Brault JJ, Sankar U, Drewry DH, Scott JW, Witczak CA, Sakamoto K. CaMKK2 is not involved in contraction-stimulated AMPK activation and glucose uptake in skeletal muscle. Mol Metab 2023; 75:101761. [PMID: 37380024 PMCID: PMC10362367 DOI: 10.1016/j.molmet.2023.101761] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 06/30/2023] Open
Abstract
OBJECTIVE The AMP-activated protein kinase (AMPK) gets activated in response to energetic stress such as contractions and plays a vital role in regulating various metabolic processes such as insulin-independent glucose uptake in skeletal muscle. The main upstream kinase that activates AMPK through phosphorylation of α-AMPK Thr172 in skeletal muscle is LKB1, however some studies have suggested that Ca2+/calmodulin-dependent protein kinase kinase 2 (CaMKK2) acts as an alternative kinase to activate AMPK. We aimed to establish whether CaMKK2 is involved in activation of AMPK and promotion of glucose uptake following contractions in skeletal muscle. METHODS A recently developed CaMKK2 inhibitor (SGC-CAMKK2-1) alongside a structurally related but inactive compound (SGC-CAMKK2-1N), as well as CaMKK2 knock-out (KO) mice were used. In vitro kinase inhibition selectivity and efficacy assays, as well as cellular inhibition efficacy analyses of CaMKK inhibitors (STO-609 and SGC-CAMKK2-1) were performed. Phosphorylation and activity of AMPK following contractions (ex vivo) in mouse skeletal muscles treated with/without CaMKK inhibitors or isolated from wild-type (WT)/CaMKK2 KO mice were assessed. Camkk2 mRNA in mouse tissues was measured by qPCR. CaMKK2 protein expression was assessed by immunoblotting with or without prior enrichment of calmodulin-binding proteins from skeletal muscle extracts, as well as by mass spectrometry-based proteomics of mouse skeletal muscle and C2C12 myotubes. RESULTS STO-609 and SGC-CAMKK2-1 were equally potent and effective in inhibiting CaMKK2 in cell-free and cell-based assays, but SGC-CAMKK2-1 was much more selective. Contraction-stimulated phosphorylation and activation of AMPK were not affected with CaMKK inhibitors or in CaMKK2 null muscles. Contraction-stimulated glucose uptake was comparable between WT and CaMKK2 KO muscle. Both CaMKK inhibitors (STO-609 and SGC-CAMKK2-1) and the inactive compound (SGC-CAMKK2-1N) significantly inhibited contraction-stimulated glucose uptake. SGC-CAMKK2-1 also inhibited glucose uptake induced by a pharmacological AMPK activator or insulin. Relatively low levels of Camkk2 mRNA were detected in mouse skeletal muscle, but neither CaMKK2 protein nor its derived peptides were detectable in mouse skeletal muscle tissue. CONCLUSIONS We demonstrate that pharmacological inhibition or genetic loss of CaMKK2 does not affect contraction-stimulated AMPK phosphorylation and activation, as well as glucose uptake in skeletal muscle. Previously observed inhibitory effect of STO-609 on AMPK activity and glucose uptake is likely due to off-target effects. CaMKK2 protein is either absent from adult murine skeletal muscle or below the detection limit of currently available methods.
Collapse
Affiliation(s)
- Florentina Negoita
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Alex B Addinsall
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Kristina Hellberg
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Conchita Fraguas Bringas
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Paul S Hafen
- Department of Anatomy, Cell Biology & Physiology, and Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Indiana Center for Diabetes & Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Division of Science, Indiana University Purdue University Columbus, Columbus, IN 47203, USA
| | - Tyler J Sermersheim
- Department of Anatomy, Cell Biology & Physiology, and Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Indiana Center for Diabetes & Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Marianne Agerholm
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Christopher T A Lewis
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Danial Ahwazi
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Naomi X Y Ling
- Metabolic Signalling, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Jeppe K Larsen
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Atul S Deshmukh
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Mohammad A Hossain
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jonathan S Oakhill
- Metabolic Signalling, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia; Department of Medicine, University of Melbourne, Parkville, VIC 3010, Australia
| | - Julien Ochala
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen 2200, Denmark
| | - Jeffrey J Brault
- Department of Anatomy, Cell Biology & Physiology, and Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Uma Sankar
- Department of Anatomy, Cell Biology & Physiology, and Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - David H Drewry
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - John W Scott
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Melbourne, VIC 3052, Australia; The Florey Institute of Neuroscience and Mental Health, Parkville, Melbourne, VIC 3052, Australia; St Vincent's Institute of Medical Research, Fitzroy, Melbourne, VIC 3065, Australia
| | - Carol A Witczak
- Department of Anatomy, Cell Biology & Physiology, and Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Indiana Center for Diabetes & Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Kei Sakamoto
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen 2200, Denmark; The Novo Nordisk Foundation Center for Genomic Mechanisms of Disease, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| |
Collapse
|
30
|
Nicastro R, Brohée L, Alba J, Nüchel J, Figlia G, Kipschull S, Gollwitzer P, Romero-Pozuelo J, Fernandes SA, Lamprakis A, Vanni S, Teleman AA, De Virgilio C, Demetriades C. Malonyl-CoA is a conserved endogenous ATP-competitive mTORC1 inhibitor. Nat Cell Biol 2023; 25:1303-1318. [PMID: 37563253 PMCID: PMC10495264 DOI: 10.1038/s41556-023-01198-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 06/29/2023] [Indexed: 08/12/2023]
Abstract
Cell growth is regulated by the mammalian/mechanistic target of rapamycin complex 1 (mTORC1), which functions both as a nutrient sensor and a master controller of virtually all biosynthetic pathways. This ensures that cells are metabolically active only when conditions are optimal for growth. Notably, although mTORC1 is known to regulate fatty acid biosynthesis, how and whether the cellular lipid biosynthetic capacity signals back to fine-tune mTORC1 activity remains poorly understood. Here we show that mTORC1 senses the capacity of a cell to synthesise fatty acids by detecting the levels of malonyl-CoA, an intermediate of this biosynthetic pathway. We find that, in both yeast and mammalian cells, this regulation is direct, with malonyl-CoA binding to the mTOR catalytic pocket and acting as a specific ATP-competitive inhibitor. When fatty acid synthase (FASN) is downregulated/inhibited, elevated malonyl-CoA levels are channelled to proximal mTOR molecules that form direct protein-protein interactions with acetyl-CoA carboxylase 1 (ACC1) and FASN. Our findings represent a conserved and unique homeostatic mechanism whereby impaired fatty acid biogenesis leads to reduced mTORC1 activity to coordinately link this metabolic pathway to the overall cellular biosynthetic output. Moreover, they reveal the existence of a physiological metabolite that directly inhibits the activity of a signalling kinase in mammalian cells by competing with ATP for binding.
Collapse
Affiliation(s)
- Raffaele Nicastro
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Laura Brohée
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany
| | - Josephine Alba
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Julian Nüchel
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany
| | - Gianluca Figlia
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- Heidelberg University, Heidelberg, Germany
| | | | - Peter Gollwitzer
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany
| | - Jesus Romero-Pozuelo
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- Heidelberg University, Heidelberg, Germany
- Unidad de Investigación Biomedica, Universidad Alfonso X El Sabio (UAX), Madrid, Spain
| | | | - Andreas Lamprakis
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland.
| | - Aurelio A Teleman
- German Cancer Research Center (DKFZ), Heidelberg, Germany.
- Heidelberg University, Heidelberg, Germany.
| | | | - Constantinos Demetriades
- Max Planck Institute for Biology of Ageing (MPI-AGE), Cologne, Germany.
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany.
| |
Collapse
|
31
|
Xu C, Pan X, Wang D, Guan Y, Yang W, Chen X, Liu Y. O-GlcNAcylation of Raptor transduces glucose signals to mTORC1. Mol Cell 2023; 83:3027-3040.e11. [PMID: 37541260 DOI: 10.1016/j.molcel.2023.07.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 05/23/2023] [Accepted: 07/11/2023] [Indexed: 08/06/2023]
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) regulates metabolism and cell growth in response to nutrient levels. Dysregulation of mTORC1 results in a broad spectrum of diseases. Glucose is the primary energy supply of cells, and therefore, glucose levels must be accurately conveyed to mTORC1 through highly responsive signaling mechanisms to control mTORC1 activity. Here, we report that glucose-induced mTORC1 activation is regulated by O-GlcNAcylation of Raptor, a core component of mTORC1, in HEK293T cells. Mechanistically, O-GlcNAcylation of Raptor at threonine 700 facilitates the interactions between Raptor and Rag GTPases and promotes the translocation of mTOR to the lysosomal surface, consequently activating mTORC1. In addition, we show that AMPK-mediated phosphorylation of Raptor suppresses Raptor O-GlcNAcylation and inhibits Raptor-Rags interactions. Our findings reveal an exquisitely controlled mechanism, which suggests how glucose coordinately regulates cellular anabolism and catabolism.
Collapse
Affiliation(s)
- Chenchen Xu
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Xiaoqing Pan
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Dong Wang
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Yuanyuan Guan
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Wenyu Yang
- Yuan Pei College, Peking University, Beijing 100871, China
| | - Xing Chen
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China; Synthetic and Functional Biomolecules Center, Peking University, Beijing 100871, China; Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Peking University, Beijing 100871, China.
| | - Ying Liu
- State Key Laboratory of Membrane Biology, New Cornerstone Science Laboratory, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Beijing Advanced Innovation Center for Genomics, Beijing 100871, China.
| |
Collapse
|
32
|
Dent JR, Stocks B, Campelj DG, Philp A. Transient changes to metabolic homeostasis initiate mitochondrial adaptation to endurance exercise. Semin Cell Dev Biol 2023; 143:3-16. [PMID: 35351374 DOI: 10.1016/j.semcdb.2022.03.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 01/26/2022] [Accepted: 03/19/2022] [Indexed: 12/14/2022]
Abstract
Endurance exercise is well established to increase mitochondrial content and function in skeletal muscle, a process termed mitochondrial biogenesis. Current understanding is that exercise initiates skeletal muscle mitochondrial remodeling via modulation of cellular nutrient, energetic and contractile stress pathways. These subtle changes in the cellular milieu are sensed by numerous transduction pathways that serve to initiate and coordinate an increase in mitochondrial gene transcription and translation. The result of these acute signaling events is the promotion of growth and assembly of mitochondria, coupled to a greater capacity for aerobic ATP provision in skeletal muscle. The aim of this review is to highlight the acute metabolic events induced by endurance exercise and the subsequent molecular pathways that sense this transient change in cellular homeostasis to drive mitochondrial adaptation and remodeling.
Collapse
Affiliation(s)
- Jessica R Dent
- Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Ben Stocks
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark
| | - Dean G Campelj
- Mitochondrial Metabolism and Ageing Laboratory, Healthy Ageing Research Theme, Garvan Institute of Medical Research, Sydney, Australia
| | - Andrew Philp
- Mitochondrial Metabolism and Ageing Laboratory, Healthy Ageing Research Theme, Garvan Institute of Medical Research, Sydney, Australia; St Vincent's Medical School, UNSW Sydney, Sydney, Australia.
| |
Collapse
|
33
|
Yang C, Li X, Yang L, Chen S, Liao J, Li K, Zhou J, Shen W, Zhuang X, Bai M, Bassham DC, Gao C. A positive feedback regulation of SnRK1 signaling by autophagy in plants. MOLECULAR PLANT 2023; 16:1192-1211. [PMID: 37408307 DOI: 10.1016/j.molp.2023.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 06/02/2023] [Accepted: 07/01/2023] [Indexed: 07/07/2023]
Abstract
SnRK1, an evolutionarily conserved heterotrimeric kinase complex that acts as a key metabolic sensor in maintaining energy homeostasis in plants, is an important upstream activator of autophagy that serves as a cellular degradation mechanism for the healthy growth of plants. However, whether and how the autophagy pathway is involved in regulating SnRK1 activity remains unknown. In this study, we identified a clade of plant-specific and mitochondria-localized FCS-like zinc finger (FLZ) proteins as currently unknown ATG8-interacting partners that actively inhibit SnRK1 signaling by repressing the T-loop phosphorylation of the catalytic α subunits of SnRK1, thereby negatively modulating autophagy and plant tolerance to energy deprivation caused by long-term carbon starvation. Interestingly, these AtFLZs are transcriptionally repressed by low-energy stress, and AtFLZ proteins undergo a selective autophagy-dependent pathway to be delivered to the vacuole for degradation, thereby constituting a positive feedback regulation to relieve their repression of SnRK1 signaling. Bioinformatic analyses show that the ATG8-FLZ-SnRK1 regulatory axis first appears in gymnosperms and seems to be highly conserved during the evolution of seed plants. Consistent with this, depletion of ATG8-interacting ZmFLZ14 confers enhanced tolerance, whereas overexpression of ZmFLZ14 leads to reduced tolerance to energy deprivation in maize. Collectively, our study reveals a previously unknown mechanism by which autophagy contributes to the positive feedback regulation of SnRK1 signaling, thereby enabling plants to better adapt to stressful environments.
Collapse
Affiliation(s)
- Chao Yang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China; Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Xibao Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Lianming Yang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Shunquan Chen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Jun Liao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Kailin Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Jun Zhou
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Wenjin Shen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Xiaohong Zhuang
- Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Mingyi Bai
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Diane C Bassham
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, Ministry of Education & Guangdong Provincial Key Laboratory of Laser Life Science, School of Life Sciences, South China Normal University, Guangzhou 510631, China.
| |
Collapse
|
34
|
Zhang Q, Feng J, Liu K, Yang X, Huang Y, Tang B. STK11 mutation impacts CD1E expression to regulate the differentiation of macrophages in lung adenocarcinoma. Immun Inflamm Dis 2023; 11:e958. [PMID: 37506141 PMCID: PMC10373563 DOI: 10.1002/iid3.958] [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: 11/02/2022] [Revised: 07/06/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
BACKGROUND The deficiency of serine/threonine protein kinase 11 (STK11), one of the most common tumor suppressor genes in non-small-cell lung cancer, is a crucial player in tumor immune microenvironment regulation. This study attempted to unveil how mutated STK11 impact the differentiation of macrophages in lung adenocarcinoma (LUAD). METHODS STK11 and CD1E expression levels in different cell models were assessed by quantitative reverse transcription polymerase chain reaction. Western blot was utilized to detect the protein expression levels of STK11, CD1E, apoptosis markers, and AMPK signaling pathway markers after transfection treatment. Cell viability and macrophage differentiation were detected by CCK-8 and flow cytometry. Immunohistochemistry and immunofluorescence were employed to detect the expression of related genes and macrophage markers, respectively. RESULTS This study found that STK11 mutations promoted the proliferation of LUAD cells and inhibited the differentiation of M1 macrophages, apoptosis, and the AMPK signaling pathway. Mutated STK11 led to CD1E downregulation, which curbed the differentiation of M1 macrophages and hence promoted LUAD progression. It was further validated by the in vivo experimental results that STK11 mutation significantly decreased the immune infiltration of M1 macrophages and promoted LUAD progression. CONCLUSION It was revealed that STK11 mutation affected CD1E expression to regulate macrophage differentiation in LUAD and then promote tumor progression. In this way, CD1E could be a potential biological target for the therapeutic interventions of STK11-mutant LUAD patients. These findings also threw new light on a new therapeutic strategy for STK11-mutant tumor patients that assisted the macrophage polarization pathway.
Collapse
Affiliation(s)
- Qingfeng Zhang
- Department of Cardio-Thoracic Surgery, Zigong Fourth People's Hospital, Zigong, China
| | - Juan Feng
- Department of Operating Room, Zigong Fourth People's Hospital, Zigong, China
| | - Kui Liu
- Department of Cardio-Thoracic Surgery, Zigong Fourth People's Hospital, Zigong, China
| | - Xiaoyan Yang
- Department of Cardio-Thoracic Surgery, Zigong Fourth People's Hospital, Zigong, China
| | - Yun Huang
- Department of Cardio-Thoracic Surgery, Zigong Fourth People's Hospital, Zigong, China
| | - Bo Tang
- Department of Cardio-Thoracic Surgery, Zigong Fourth People's Hospital, Zigong, China
| |
Collapse
|
35
|
Crewe C. Energetic Stress-Induced Metabolic Regulation by Extracellular Vesicles. Compr Physiol 2023; 13:5051-5068. [PMID: 37358503 PMCID: PMC10414774 DOI: 10.1002/cphy.c230001] [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] [Indexed: 06/27/2023]
Abstract
Recent studies have demonstrated that extracellular vesicles (EVs) serve powerful and complex functions in metabolic regulation and metabolic-associated disease, although this field of research is still in its infancy. EVs are released into the extracellular space from all cells and carry a wide range of cargo including miRNAs, mRNA, DNA, proteins, and metabolites that have robust signaling effects in receiving cells. EV production is stimulated by all major stress pathways and, as such, has a role in both restoring homeostasis during stress and perpetuating disease. In metabolic regulation, the dominant stress signal is a lack of energy due to either nutrient deficits or damaged mitochondria from nutrient excess. This stress signal is termed "energetic stress," which triggers a robust and evolutionarily conserved response that engages major cellular stress pathways, the ER unfolded protein response, the hypoxia response, the antioxidant response, and autophagy. This article proposes the model that energetic stress is the dominant stimulator of EV release with a focus on metabolically important cells such as hepatocytes, adipocytes, myocytes, and pancreatic β-cells. Furthermore, this article will discuss how the cargo in stress-stimulated EVs regulates metabolism in receiving cells in both beneficial and detrimental ways. © 2023 American Physiological Society. Compr Physiol 13:5051-5068, 2023.
Collapse
Affiliation(s)
- Clair Crewe
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
36
|
Takizawa Y, Kizawa M, Niwa N, Komura Y, Takahashi M, Koda D, Kurita T, Nakajima T. Specific inhibitory effects of guanosine on breast cancer cell proliferation. Biochem Biophys Res Commun 2023; 673:67-72. [PMID: 37356147 DOI: 10.1016/j.bbrc.2023.06.069] [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: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 06/27/2023]
Abstract
Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer-related death. Drug therapy for breast cancer is currently selected based on the subtype classification; however, many anticancer drugs are highly cytotoxic. Since intracellular levels of GTP are elevated in many cancer cells that undergo a specific cell proliferation cycle, GTP has potential as a target for cancer therapy. The present study focused on nucleosides and nucleotides and examined intracellular GTP-dependent changes in cell proliferation rates in normal (MCF-12A) and cancer (MCF-7) breast cell lines. Decreased cell proliferation due to a reduction in intracellular GTP levels by mycophenolic acid (MPA), an inosine monophosphate dehydrogenase inhibitor, was observed in both cell lines. The inhibitory effects of MPA on cell proliferation were suppressed when it was applied in combination with Guanosine (Guo), a substrate for GTP salvage synthesis, while the single exposure to Guo suppressed the proliferation of MCF-7 cells only. Although the underlying mechanisms remain unclear, since the inhibitory effects of Guo on cell proliferation did not correlate with GTP or ATP intracellular levels or the GTP/ATP ratio, there may be another cause besides GTP metabolism. Guo inhibited the proliferation of MCF-7, a human breast cancer cell line, but not MCF-12A, a human normal breast cell line. Further studies are needed to investigate the potential of applying Guo as a target for the development of a novel cancer treatment system.
Collapse
Affiliation(s)
- Yusuke Takizawa
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan.
| | - Masayuki Kizawa
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Nobuyuki Niwa
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Yuya Komura
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Masato Takahashi
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Daiki Koda
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Takuro Kurita
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Takanori Nakajima
- Division of Clinical Pharmaceutics, Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| |
Collapse
|
37
|
Carmona B, Marinho HS, Matos CL, Nolasco S, Soares H. Tubulin Post-Translational Modifications: The Elusive Roles of Acetylation. BIOLOGY 2023; 12:biology12040561. [PMID: 37106761 PMCID: PMC10136095 DOI: 10.3390/biology12040561] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/27/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023]
Abstract
Microtubules (MTs), dynamic polymers of α/β-tubulin heterodimers found in all eukaryotes, are involved in cytoplasm spatial organization, intracellular transport, cell polarity, migration and division, and in cilia biology. MTs functional diversity depends on the differential expression of distinct tubulin isotypes and is amplified by a vast number of different post-translational modifications (PTMs). The addition/removal of PTMs to α- or β-tubulins is catalyzed by specific enzymes and allows combinatory patterns largely enriching the distinct biochemical and biophysical properties of MTs, creating a code read by distinct proteins, including microtubule-associated proteins (MAPs), which allow cellular responses. This review is focused on tubulin-acetylation, whose cellular roles continue to generate debate. We travel through the experimental data pointing to α-tubulin Lys40 acetylation role as being a MT stabilizer and a typical PTM of long lived MTs, to the most recent data, suggesting that Lys40 acetylation enhances MT flexibility and alters the mechanical properties of MTs, preventing MTs from mechanical aging characterized by structural damage. Additionally, we discuss the regulation of tubulin acetyltransferases/desacetylases and their impacts on cell physiology. Finally, we analyze how changes in MT acetylation levels have been found to be a general response to stress and how they are associated with several human pathologies.
Collapse
Affiliation(s)
- Bruno Carmona
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Av. D. João II, Lote 4.69.01, 1990-096 Lisboa, Portugal
| | - H Susana Marinho
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Catarina Lopes Matos
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Sofia Nolasco
- Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Av. D. João II, Lote 4.69.01, 1990-096 Lisboa, Portugal
- CIISA-Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Helena Soares
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Av. D. João II, Lote 4.69.01, 1990-096 Lisboa, Portugal
| |
Collapse
|
38
|
Xiao WC, Zhou G, Wan L, Tu J, Yu YJ, She ZG, Xu CL, Wang L. Carnosol inhibits cerebral ischemia-reperfusion injury by promoting AMPK activation. Brain Res Bull 2023; 195:37-46. [PMID: 36775042 DOI: 10.1016/j.brainresbull.2023.02.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 02/12/2023]
Abstract
BACKGROUND Carnosol is a phytopolyphenol (diterpene) found and extracted from plants of Mediterranean diet, which has anti-tumor, anti-inflammatory and antioxidant effects. However, its role in ischemic stroke has not been elucidated. METHODS Primary neurons subjected to oxygen-glucose deprivation (OGD) was used to investigate the effect of carnosol in vitro. A mouse MCAO model was used to evaluate the effect of carnosol on ischemic stroke in vivo. The mRNA level of inflammatory and apoptosis-related genes was determined by RT-PCR. The protein level of total and phosphorylated AMPK was determined by WB. H&E and Immunofluorescent assay was used to investigate the necrosis, inflammation and apoptosis in brain tissue. RESULTS Carnosol protected the activity of primary neurons subjected to oxygen-glucose deprivation (OGD) in vitro, as well as inhibited inflammation and apoptosis. Furthermore, carnosol could significantly reduce the infarct and edema volume and protect against neurological deficit in vivo, and had a significant inhibitory effect on brain neuroinflammation and apoptosis. Mechanically, carnosol could activate AMPK, and the effect of carnosol on cerebral ischemia-reperfusion injury cell model could be abolished by AMPK phosphorylation inhibitor. CONCLUSION Carnosol has a protective effect on ischemic stroke, and this effect is achieved through AMPK activation. Our study demonstrates the protective effect of carnosol on cerebral ischemia-reperfusion injury and provides a new perspective for the clinical treatment of ischemic stroke.
Collapse
Affiliation(s)
- Wen-Chang Xiao
- Department of Cardiovascular Surgery, Huanggang Central Hospital, Huanggang, China; Huanggang Institute of Translational Medicine, Huanggang, China.
| | - Gang Zhou
- Department of Neurology, Huanggang Central Hospital, Huanggang, China.
| | - Lu Wan
- Department of Neurosurgery, Huanggang Central Hospital, Huanggang, China.
| | - Jun Tu
- Huanggang Institute of Translational Medicine, Huanggang, China.
| | - Yong-Jie Yu
- Huanggang Institute of Translational Medicine, Huanggang, China.
| | - Zhi-Gang She
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China.
| | - Chun-Lin Xu
- Department of Neurosurgery, Huanggang Central Hospital, Huanggang, China.
| | - Lei Wang
- Department of Neurosurgery, Huanggang Central Hospital, Huanggang, China.
| |
Collapse
|
39
|
Zhu JG, Xie P, Song C, Liu TW, Gong DQ. Differential expression of glucose metabolism-related genes and AMP-activated protein kinases in crop tissue of male and female pigeons (Columba livia domestica) during the incubation and chick-rearing periods. J Anim Physiol Anim Nutr (Berl) 2023; 107:680-690. [PMID: 35668622 DOI: 10.1111/jpn.13741] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 05/12/2022] [Accepted: 05/16/2022] [Indexed: 11/29/2022]
Abstract
The objective of this study was to explore the carbohydrate contents of crop milk, insulin and glucose concentrations in serum and the expression patterns of AMP-activated protein kinases (AMPKs) and genes related to glucose metabolism in pigeon crops during the breeding period. Crop milk was collected from squabs of rearing Day 1 (R1) to R6. Contents of total sugar and reducing sugar increased to the maximum levels at R6 (p < 0.05). Forty-two pairs of adult pigeons were allotted to seven groups by different breeding stages, and their crops and serum were sampled. No significant differences were found in either insulin or glucose levels in serum. The glucose transporter 2 gene level was the greatest at R15 in females, whereas it was at R7 in males. However, sodium-dependent glucose transporters 1 expression in both sexes decreased from incubation Day 17 (I17) to R7. In females, glucokinase expression peaked at R1, and at R1 and R7 in males. Pyruvate kinase mRNA levels peaked at R7 in females and at R15 males. The mRNA abundance of fructose-1,6-bisphosphatase 1 in both sexes and glucose-6-phosphatase in females decreased after I10. While phosphoenolpyruvate carboxykinase 1 expression decreased after I17 (p < 0.05). Protein levels of AMPKα in crops were minimized at R1 (p < 0.05). In females, expression of AMPKα1 and AMPKα2 was inhibited at I17 and R1 (p < 0.05). In males, AMPKα1 expression was decreased at R7 (p < 0.05) and AMPKα2 was reduced at I10 and R1. pAMPK expression was the lowest at I17 in females, and it was at R7 and R25 in males. Conclusively, glycolysis in pigeon crops was enhanced during chick-rearing, while gluconeogenesis was significantly inhibited. The stability of the insulin level suggests that it was probably not involved in the regulation of glucose metabolism in crop tissues.
Collapse
Affiliation(s)
- Jian-Guo Zhu
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China.,Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huaiyin Normal University, Huaian, China
| | - Peng Xie
- Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huaiyin Normal University, Huaian, China.,Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake, Huaiyin Normal University, Huaian, China
| | - Chao Song
- Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huaiyin Normal University, Huaian, China.,Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake, Huaiyin Normal University, Huaian, China
| | - Ting-Wu Liu
- Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huaiyin Normal University, Huaian, China.,Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake, Huaiyin Normal University, Huaian, China
| | - Dao-Qing Gong
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| |
Collapse
|
40
|
Pappas G, Wilkinson ML, Gow AJ. Nitric oxide regulation of cellular metabolism: Adaptive tuning of cellular energy. Nitric Oxide 2023; 131:8-17. [PMID: 36470373 PMCID: PMC9839556 DOI: 10.1016/j.niox.2022.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/24/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022]
Abstract
Nitric oxide can interact with a wide range of proteins including many that are involved in metabolism. In this review we have summarized the effects of NO on glycolysis, fatty acid metabolism, the TCA cycle, and oxidative phosphorylation with reference to skeletal muscle. Low to moderate NO concentrations upregulate glucose and fatty acid oxidation, while higher NO concentrations shift cellular reliance toward a fully glycolytic phenotype. Moderate NO production directly inhibits pyruvate dehydrogenase activity, reducing glucose-derived carbon entry into the TCA cycle and subsequently increasing anaploretic reactions. NO directly inhibits aconitase activity, increasing reliance on glutamine for continued energy production. At higher or prolonged NO exposure, citrate accumulation can inhibit multiple ATP-producing pathways. Reduced TCA flux slows NADH/FADH entry into the ETC. NO can also inhibit the ETC directly, further limiting oxidative phosphorylation. Moderate NO production improves mitochondrial efficiency while improving O2 utilization increasing whole-body energy production. Long-term bioenergetic capacity may be increased because of NO-derived ROS, which participate in adaptive cellular redox signaling through AMPK, PCG1-α, HIF-1, and NF-κB. However, prolonged exposure or high concentrations of NO can result in membrane depolarization and opening of the MPT. In this way NO may serve as a biochemical rheostat matching energy supply with demand for optimal respiratory function.
Collapse
Affiliation(s)
- Gregory Pappas
- Department of Kinesiology & Applied Physiology, Rutgers the State University of New Jersey, NJ, 08854, USA.
| | - Melissa L Wilkinson
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers the State University of New Jersey, NJ, 08854, USA.
| | - Andrew J Gow
- Department of Kinesiology & Applied Physiology, Rutgers the State University of New Jersey, NJ, 08854, USA; Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers the State University of New Jersey, NJ, 08854, USA.
| |
Collapse
|
41
|
Huynh C, Ryu J, Lee J, Inoki A, Inoki K. Nutrient-sensing mTORC1 and AMPK pathways in chronic kidney diseases. Nat Rev Nephrol 2023; 19:102-122. [PMID: 36434160 DOI: 10.1038/s41581-022-00648-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2022] [Indexed: 11/27/2022]
Abstract
Nutrients such as glucose, amino acids and lipids are fundamental sources for the maintenance of essential cellular processes and homeostasis in all organisms. The nutrient-sensing kinases mechanistic target of rapamycin (mTOR) and AMP-activated protein kinase (AMPK) are expressed in many cell types and have key roles in the control of cell growth, proliferation, differentiation, metabolism and survival, ultimately contributing to the physiological development and functions of various organs, including the kidney. Dysregulation of these kinases leads to many human health problems, including cancer, neurodegenerative diseases, metabolic disorders and kidney diseases. In the kidney, physiological levels of mTOR and AMPK activity are required to support kidney cell growth and differentiation and to maintain kidney cell integrity and normal nephron function, including transport of electrolytes, water and glucose. mTOR forms two functional multi-protein kinase complexes, mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). Hyperactivation of mTORC1 leads to podocyte and tubular cell dysfunction and vulnerability to injury, thereby contributing to the development of chronic kidney diseases, including diabetic kidney disease, obesity-related kidney disease and polycystic kidney disease. Emerging evidence suggests that targeting mTOR and/or AMPK could be an effective therapeutic approach to controlling or preventing these diseases.
Collapse
Affiliation(s)
- Christopher Huynh
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.,Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jaewhee Ryu
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Jooho Lee
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Ayaka Inoki
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA.,Department of Internal Medicine, Division of Nephrology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ken Inoki
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA. .,Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA. .,Department of Internal Medicine, Division of Nephrology, University of Michigan Medical School, Ann Arbor, MI, USA.
| |
Collapse
|
42
|
AMPK inhibits liver gluconeogenesis: fact or fiction? Biochem J 2023; 480:105-125. [PMID: 36637190 DOI: 10.1042/bcj20220582] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/21/2022] [Accepted: 01/04/2023] [Indexed: 01/14/2023]
Abstract
Is there a role for AMPK in the control of hepatic gluconeogenesis and could targeting AMPK in liver be a viable strategy for treating type 2 diabetes? These are frequently asked questions this review tries to answer. After describing properties of AMPK and different small-molecule AMPK activators, we briefly review the various mechanisms for controlling hepatic glucose production, mainly via gluconeogenesis. The different experimental and genetic models that have been used to draw conclusions about the role of AMPK in the control of liver gluconeogenesis are critically discussed. The effects of several anti-diabetic drugs, particularly metformin, on hepatic gluconeogenesis are also considered. We conclude that the main effect of AMPK activation pertinent to the control of hepatic gluconeogenesis is to antagonize glucagon signalling in the short-term and, in the long-term, to improve insulin sensitivity by reducing hepatic lipid content.
Collapse
|
43
|
Chen W, Zhao Z, Cen S, Lv D, Wu J, Zhou X, Yang T, Zhao T, Hou L, Mao X. Exposure to elevated temperature affects the expression of PIWI-interacting RNAs and associated transcripts in mouse testes. Andrology 2023; 11:724-737. [PMID: 36603597 DOI: 10.1111/andr.13381] [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: 07/27/2022] [Revised: 12/21/2022] [Accepted: 01/02/2023] [Indexed: 01/07/2023]
Abstract
BACKGROUND Exposure to heat waves could result in adverse effects on human health, especially in male testicles. PIWI-interacting RNA (piRNA) is a novel type of small non-coding RNA, which can notably impact mRNA turnover and preserve germline maintenance in germline cells. However, piRNA's expression status when adapting to testicular heat stress remains largely unclear. OBJECTIVES To investigate the function and mechanisms of relevant piRNAs during testicular heat stress. MATERIALS AND METHODS In this study, a mouse testicular heat stress model was constructed, and the testes were removed for piRNA-sequencing. Bioinformatics analysis was used to discover the differential expressed piRNAs, piRNA clusters, and enriched pathways. A cell heat stress model was constructed to validate the top five upregulated piRNAs. Proliferation and apoptosis assays were utilized to validate the function of selected piRNA. Bioinformatics prediction, western blotting, and immunohistochemistry were used to illustrate the downstream mechanisms. RESULTS Through the bioinformatics analysis, we identified the differential expression profile and enriched pathways of piRNAs and piRNA clusters during testicular hyperthermia. Besides, piR-020492 was proved to be upregulated in heat stress mouse testes and a germ cell model. A series of in vitro assays illustrated that an overexpression of piR-020492 could restrain the proliferation and promote the apoptosis of mouse germ cells. Kyoto Encyclopedia of Genes and Genomes analysis of piRNA-generating genes in the testicular heat stress model and piR-020492 targeting genes showed that the overlap pathways are adenosine monophosphate-activated protein kinase (AMPK) and insulin pathways. Validation experiments demonstrated that the key genes of AMPK and insulin pathway exhibit differential expression after an overexpression of piR-020492 or testicular heat stress. DISCUSSION AND CONCLUSION In conclusion, our findings revealed the expression profile of piRNAs in testicular heat stress and illustrated the function and mechanisms of piR-020492 in germ cells, which could provide novel insights into the mechanism of hyperthermia-induced testicular injury.
Collapse
Affiliation(s)
- Wenbin Chen
- Department of Urology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhang Zhao
- Department of Urology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Shengren Cen
- Department of Urology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Daojun Lv
- Department of Urology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Jun Wu
- Department of Urology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xumin Zhou
- Department of Urology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Taowei Yang
- Department of Urology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Tianxin Zhao
- Department of Urology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Longlong Hou
- Department of Neonatal Surgery, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Xiangming Mao
- Department of Urology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| |
Collapse
|
44
|
Li J, Peng G, Yu Y, Lin B, Zhang L, Guo M, Cao Y, Wang Y. Cu 2+-mediated turn-on fluorescence biosensor based on DNA-templated silver nanoclusters for label-free and sensitive detection of adenosine triphosphate. Mikrochim Acta 2022; 190:41. [PMID: 36585965 DOI: 10.1007/s00604-022-05617-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 12/07/2022] [Indexed: 01/01/2023]
Abstract
A Cu2+-mediated turn-on fluorescence biosensor based on the DNA-templated green-emitting silver nanoclusters (DNA@g-AgNCs) was developed for label-free and sensitive detection of adenosine 5'-triphosphate (ATP). Cu2+ was able to quench the bright green fluorescence of DNA@g-AgNCs because of the coordination and photoinduced electron transfer between DNA@g-AgNCs and Cu2+. Therefore, a unique and effective fluorescence biosensor can be constructed with the formation of DNA@g-AgNCs/Cu2+/ATP ternary-competition system. With the introduction of ATP, the DNA@g-AgNCs/Cu2+ fluorescence sensing system will be disrupted and the fluorescence of DNA@g-AgNCs was recovered due to higher affinity of ATP towards Cu2+. On the basis of this feature, the DNA@g-AgNCs/Cu2+ fluorescence sensing system demonstrated quantitative determination of ATP in the range 0.05 - 3 μM and a detection limit of 16 nM. Moreover, the fluorescence sensing system was successfully applied to the quantitative determination of ATP in human urine and serum samples with recoveries ranging from 98.6 to 106.5%, showing great promise to provide a label-free, cost-efficient, and rapid platform for ATP-related clinical disease diagnosis.
Collapse
Affiliation(s)
- Jingze Li
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China
- School of Materials Engineering, Jiangxi College of Applied Technology, Ganzhou, Jiangxi, 341000, People's Republic of China
| | - Guibin Peng
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China
| | - Ying Yu
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China.
| | - Bixia Lin
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China
| | - Li Zhang
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China
| | - Manli Guo
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China
| | - Yujuan Cao
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China
| | - Yumin Wang
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China.
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin, Guangxi, 541004, People's Republic of China.
| |
Collapse
|
45
|
Anggreini P, Kuncoro H, Sumiwi SA, Levita J. Role of the AMPK/SIRT1 pathway in non‑alcoholic fatty liver disease (Review). Mol Med Rep 2022; 27:35. [PMID: 36562343 PMCID: PMC9827347 DOI: 10.3892/mmr.2022.12922] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 10/26/2022] [Indexed: 12/24/2022] Open
Abstract
Non‑alcoholic fatty liver disease (NAFLD) is an increasingly prevalent ailment worldwide. Moreover, de novo lipogenesis (DNL) is considered a critical factor in the development of NAFLD; hence, its inhibition is a promising target for the prevention of fatty liver disease. There is evidence to indicate that AMP‑activated protein kinase (AMPK) and sirtuin 1 (SIRT1) may play a crucial role in DNL and are the regulatory proteins in type 2 diabetes mellitus, obesity and cardiovascular disease. Therefore, AMPK and SIRT1 may be promising targets for the treatment of NAFLD. The present review article thus aimed to summarize the findings of clinical studies published during the past decade that suggested the beneficial effects of AMPK and SIRT1, using their specific activators and their combined effects on fatty liver disease.
Collapse
Affiliation(s)
- Putri Anggreini
- Doctoral Program in Pharmacy, Faculty of Pharmacy, Padjadjaran University, Sumedang, West Java 46363, Indonesia,Laboratory of Pharmaceutical Research and Development, Faculty of Pharmacy, Mulawarman University, Samarinda, East Borneo 75119, Indonesia
| | - Hadi Kuncoro
- Laboratory of Pharmaceutical Research and Development, Faculty of Pharmacy, Mulawarman University, Samarinda, East Borneo 75119, Indonesia,Correspondence to: Dr Hadi Kuncoro, Laboratory of Pharmaceutical Research and Development, Faculty of Pharmacy, Mulawarman University, Muara Muntai Street, Gunung Kelua, Samarinda, East Borneo 75119, Indonesia, E-mail:
| | - Sri Adi Sumiwi
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Padjadjaran University, Sumedang, West Java 46363, Indonesia
| | - Jutti Levita
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Padjadjaran University, Sumedang, West Java 46363, Indonesia
| |
Collapse
|
46
|
Zhou Q, Hao B, Cao X, Gao L, Yu Z, Zhao Y, Zhu M, Zhong G, Chi F, Dai X, Mao J, Zhu Y, Rong P, Chen L, Bai X, Ye C, Chen S, Liang T, Li L, Feng XH, Tan M, Zhao B. Energy sensor AMPK gamma regulates translation via phosphatase PPP6C independent of AMPK alpha. Mol Cell 2022; 82:4700-4711.e12. [PMID: 36384136 DOI: 10.1016/j.molcel.2022.10.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 09/02/2022] [Accepted: 10/25/2022] [Indexed: 11/17/2022]
Abstract
Maintenance of energy level to drive movements and material exchange with the environment is a basic principle of life. AMP-activated protein kinase (AMPK) senses energy level and is a major regulator of cellular energy responses. The gamma subunit of AMPK senses elevated ratio of AMP to ATP and allosterically activates the alpha catalytic subunit to phosphorylate downstream effectors. Here, we report that knockout of AMPKγ, but not AMPKα, suppressed phosphorylation of eukaryotic translation elongation factor 2 (eEF2) induced by energy starvation. We identified PPP6C as an AMPKγ-regulated phosphatase of eEF2. AMP-bound AMPKγ sequesters PPP6C, thereby blocking dephosphorylation of eEF2 and thus inhibiting translation elongation to preserve energy and to promote cell survival. Further phosphoproteomic analysis identified additional targets of PPP6C regulated by energy stress in an AMPKγ-dependent manner. Thus, AMPKγ senses cellular energy availability to regulate not only AMPKα kinase, but also PPP6C phosphatase and possibly other effectors.
Collapse
Affiliation(s)
- Qi Zhou
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Bingbing Hao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xiaolei Cao
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Lin Gao
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Zhenyue Yu
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Yang Zhao
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Mingrui Zhu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Guoxuan Zhong
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Fangtao Chi
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Xiaoming Dai
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Jizhong Mao
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Yibing Zhu
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Ping Rong
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, Nanjing 210061, China
| | - Liang Chen
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, Nanjing 210061, China
| | - Xueli Bai
- Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Cunqi Ye
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Shuai Chen
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, Nanjing 210061, China
| | - Tingbo Liang
- Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Li Li
- Institute of Aging Research, Hangzhou Normal University, Hangzhou 311121, China
| | - Xin-Hua Feng
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China.
| | - Minjia Tan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
| | - Bin Zhao
- MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Cancer Center, Zhejiang University, Hangzhou 310058, China; Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China; Center for Life Sciences, Shaoxing Institute, Zhejiang University, Shaoxing 321000, China.
| |
Collapse
|
47
|
Xu P, Zheng Y, Liao J, Hu M, Yang Y, Zhang B, Kilby MD, Fu H, Liu Y, Zhang F, Xiong L, Liu X, Jin H, Wu Y, Huang J, Han T, Wen L, Gao R, Fu Y, Fan X, Qi H, Baker PN, Tong C. AMPK regulates homeostasis of invasion and viability in trophoblasts by redirecting glucose metabolism: Implications for pre-eclampsia. Cell Prolif 2022; 56:e13358. [PMID: 36480593 PMCID: PMC9890534 DOI: 10.1111/cpr.13358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 12/13/2022] Open
Abstract
Pre-eclampsia (PE) is deemed an ischemia-induced metabolic disorder of the placenta due to defective invasion of trophoblasts during placentation; thus, the driving role of metabolism in PE pathogenesis is largely ignored. Since trophoblasts undergo substantial glycolysis, this study aimed to investigate its function and regulatory mechanism by AMPK in PE development. Metabolomics analysis of PE placentas was performed by gas chromatography-mass spectrometry (GC-MS). Trophoblast-specific AMPKα1-deficient mouse placentas were generated to assess morphology. A mouse PE model was established by Reduced Uterine Perfusion Pressure, and placental AMPK was modulated by nanoparticle-delivered A769662. Trophoblast glucose uptake was measured by 2-NBDG and 2-deoxy-d-[3 H] glucose uptake assays. Cellular metabolism was investigated by the Seahorse assay and GC-MS.PE complicated trophoblasts are associated with AMPK hyperactivation due not to energy deficiency. Thereafter, AMPK activation during placentation exacerbated PE manifestations but alleviated cell death in the placenta. AMPK activation in trophoblasts contributed to GLUT3 translocation and subsequent glucose metabolism, which were redirected into gluconeogenesis, resulting in deposition of glycogen and accumulation of phosphoenolpyruvate; the latter enhanced viability but compromised trophoblast invasion. However, ablation of AMPK in the mouse placenta resulted in decreased glycogen deposition and structural malformation. These data reveal a novel homeostasis between invasiveness and viability in trophoblasts, which is mechanistically relevant for switching between the 'go' and 'grow' cellular programs.
Collapse
Affiliation(s)
- Ping Xu
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina,Biochemistry and Molecular BiologyUniversity of Texas McGovern Medical SchoolHoustonTexasUSA
| | - Yangxi Zheng
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina,Department of Stem Cell Transplantation and Cell TherapyMD Anderson Cancer CenterHoustonTexasUSA
| | - Jiujiang Liao
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Mingyu Hu
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Yike Yang
- Department of Gynecology and ObstetricsPeking University Third HospitalBeijingChina
| | - Baozhen Zhang
- Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdongChina
| | - Mark D. Kilby
- Institute of Metabolism and System ResearchUniversity of BirminghamEdgbastonUK
| | - Huijia Fu
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Yamin Liu
- Department of ObstetricsWomen and Children's Hospital of Chongqing Medical UniversityChongqingChina
| | - Fumei Zhang
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Liling Xiong
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Xiyao Liu
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Huili Jin
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Yue Wu
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Jiayu Huang
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Tingli Han
- Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Li Wen
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Rufei Gao
- Laboratory of Reproductive Biology, School of Public Health and ManagementChongqing Medical UniversityChongqingChina
| | - Yong Fu
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| | - Xiujun Fan
- Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdongChina
| | - Hongbo Qi
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina,Department of ObstetricsWomen and Children's Hospital of Chongqing Medical UniversityChongqingChina
| | | | - Chao Tong
- State Key Laboratory of Maternal and Fetal Medicine of Chongqing MunicipalityThe First Affiliated Hospital of Chongqing Medical UniversityChongqingChina,Ministry of Education‐International Collaborative Laboratory of Reproduction and DevelopmentChongqing Medical UniversityChongqingChina
| |
Collapse
|
48
|
Liu Y, Wang X, Gong R, Xu G, Zhu M. Overexpression of Rhodopsin or Its Mutants Leads to Energy Metabolism Dysfunction in 661w Cells. Invest Ophthalmol Vis Sci 2022; 63:2. [PMID: 36469028 PMCID: PMC9730732 DOI: 10.1167/iovs.63.13.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose Retinitis pigmentosa (RP) is a heterogeneous group of inherited disorders characterized by photoreceptor degeneration. The rhodopsin gene (RHO) is the most frequent cause of autosomal dominant RP (ADRP), yet it remains unclear how RHO mutations cause heterogeneous phenotypes. Energy failure is a main cause of the secondary cone death during RP progression; however, its role in primary rod death induced by ADRP RHO mutants is unknown. Methods Three RHO missense mutations were chosen from different clinical classes. Wild-type (WT) RHO and its mutants, P23H (class B1), R135L (class A), and G188R (class B2), were overexpressed in 661w cells, a mouse photoreceptor cell line, and their effects on oxidative phosphorylation (OXPHOS) and aerobic glycolysis were compared separately. Results Here, we report that energy failure is an early event in the cell death caused by overexpression of WT RHO and its mutants. RHO overexpression leads to OXPHOS deficiency, which might be a result of mitochondrial loss. Nonetheless, only in WT RHO and P23H groups, energy stress triggers AMP-activated protein kinase activation and metabolic reprogramming to increase glycolysis. Metabolic reprogramming impairment in R135L and G188R groups might be the reason why energy failure and cell injury are much more severe in those groups. Conclusions Our results imply that overexpression of RHO missense mutants have distinct impacts on the two energy metabolic pathways, which might be related to their heterogeneous phenotypes.
Collapse
Affiliation(s)
- Yang Liu
- Shanghai Key Laboratory of Visual Impairment and Restoration, Eye & ENT Hospital, Fudan University, Shanghai, China,NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Xin Wang
- Shanghai Key Laboratory of Visual Impairment and Restoration, Eye & ENT Hospital, Fudan University, Shanghai, China,NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Ruowen Gong
- Shanghai Key Laboratory of Visual Impairment and Restoration, Eye & ENT Hospital, Fudan University, Shanghai, China,NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Gezhi Xu
- Shanghai Key Laboratory of Visual Impairment and Restoration, Eye & ENT Hospital, Fudan University, Shanghai, China,NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Min Zhu
- Shanghai Key Laboratory of Visual Impairment and Restoration, Eye & ENT Hospital, Fudan University, Shanghai, China,NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| |
Collapse
|
49
|
Zhou Y, Liu F. Coordination of the AMPK, Akt, mTOR, and p53 Pathways under Glucose Starvation. Int J Mol Sci 2022; 23:ijms232314945. [PMID: 36499271 PMCID: PMC9741397 DOI: 10.3390/ijms232314945] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/24/2022] [Accepted: 11/25/2022] [Indexed: 12/02/2022] Open
Abstract
Glucose is a direct energy source for eukaryotic cells, and its deficiency elicits complex stress responses and diverse cellular outcomes. Although several signaling pathways involved have been identified, how they coordinately dictate the cell fate remains obscure. We propose a minimal network model for the cellular response to glucose restriction, characterizing the glucose uptake and signaling of the AMPK, Akt, mTOR, and p53 pathways. We demonstrate that in the presence of sufficient growth factors and amino acids, cells may undergo proliferation, senescence, or apoptosis, depending on the extracellular glucose level. AMPK is first activated upon glucose limitation, activating p53 to induce cell-cycle arrest; possibly, cells resume proliferation after timely glucose restoration. For long-term energy stress, cell senescence is maintained by low/intermediate levels of p53 and persistent activation of mTOR and Akt, or cells commit apoptosis when the proteins undergo biphasic dynamics, e.g., p53 switches from intermediate levels to high levels while mTOR and Akt become inactivated in the later phase. The biphasic dynamics of p53 are associated with flipping of two bistable switches. Appropriate mTOR levels are required for optimal cell-fate decision. This work suggests that senescence and apoptosis occur sequentially in glucose-depleted cells, and a theoretical framework is provided for exploring the cellular response to energy stress.
Collapse
|
50
|
Ding Q, Wang Y, Xia SW, Zhao F, Zhong JF, Wang HL, Chen KL. SIRT4 Expression Ameliorates the Detrimental Effect of Heat Stress via AMPK/mTOR Signaling Pathway in BMECs. Int J Mol Sci 2022; 23:13307. [PMID: 36362094 PMCID: PMC9658231 DOI: 10.3390/ijms232113307] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 10/27/2022] [Accepted: 10/27/2022] [Indexed: 08/29/2023] Open
Abstract
Sirtuin 4 (SIRT4), a member of the SIRT family, has been reported to be a key factor involved in antioxidant defense in mitochondria. This study aimed to explore the potential molecular mechanism via which SIRT4 regulates heat stress-induced oxidative stress and lactoprotein synthesis in bovine mammary epithelial cells (BMECs). Our results showed that SIRT4 was significantly decreased in heat stressed mammary tissue. Depletion of SIRT4 in BMECs induced the generation of ROS, which, as exhibited by the decreased activity of antioxidant enzymes, changed mitochondrial morphology through mediating protein and mRNA levels related to mitochondrial fission and fusion. Moreover, we found that depletion of SIRT4 or stress conditions inhibited the expression of milk proteins, as well as lipid and glucose synthesis-related genes, and activated the AMPK/mTOR signaling pathway. Increased SIRT4 expression was found to have the opposite effect. However, blocking the AMPK/mTOR signaling pathway could inhibit the regulatory function of SIRT4 in milk synthesis-related gene expression. In summary, our results suggest that SIRT4 may play critical roles in maintaining mammary gland function by regulating the AMPK/mTOR signaling pathway in dairy cows, indicating that SIRT4 may be a potential molecular target for curing heat stress-induced BMEC injury and low milk production in dairy cows.
Collapse
Affiliation(s)
| | | | | | | | | | - Hui-Li Wang
- Key Laboratory of Crop and Animal Integrated Farming/Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Nanjing 210014, China
| | - Kun-Lin Chen
- Key Laboratory of Crop and Animal Integrated Farming/Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Nanjing 210014, China
| |
Collapse
|