1
|
Marsh NM, MacEwen MJS, Chea J, Kenerson HL, Kwong AA, Locke TM, Miralles FJ, Sapre T, Gozali N, Atilla-Gokcumen GE, Ong SE, Scott JD, Yeung RS, Sancak Y. Mitochondrial Calcium Signaling Regulates Branched-Chain Amino Acid Catabolism in Fibrolamellar Carcinoma. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.27.596106. [PMID: 38853984 PMCID: PMC11160645 DOI: 10.1101/2024.05.27.596106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Metabolic adaptations in response to changes in energy supply and demand are essential for survival. The mitochondrial calcium uniporter coordinates metabolic homeostasis by regulating TCA cycle activation, mitochondrial fatty acid oxidation and cellular calcium signaling. However, a comprehensive analysis of uniporter-regulated mitochondrial metabolic pathways has remained unexplored. Here, we investigate the metabolic consequences of uniporter loss- and gain-of-function, and identify a key transcriptional regulator that mediates these effects. Using gene expression profiling and proteomic, we find that loss of uniporter function increases the expression of proteins in the branched-chain amino acid (BCAA) catabolism pathway. Activity is further augmented through phosphorylation of the enzyme that catalyzes this pathway's committed step. Conversely, in the liver cancer fibrolamellar carcinoma (FLC)-which we demonstrate to have high mitochondrial calcium levels- expression of BCAA catabolism enzymes is suppressed. We also observe uniporter-dependent suppression of the transcription factor KLF15, a master regulator of liver metabolic gene expression, including those involved in BCAA catabolism. Notably, loss of uniporter activity upregulates KLF15, along with its transcriptional target ornithine transcarbamylase (OTC), a component of the urea cycle, suggesting that uniporter hyperactivation may contribute to the hyperammonemia observed in FLC patients. Collectively, we establish that FLC has increased mitochondrial calcium levels, and identify an important role for mitochondrial calcium signaling in metabolic adaptation through the transcriptional regulation of metabolism.
Collapse
Affiliation(s)
- Nicole M Marsh
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - Melissa J S MacEwen
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - Jane Chea
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - Heidi L Kenerson
- Department of Surgery, University of Washington Medical Center, Seattle, WA, United States
| | - Albert A Kwong
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - Timothy M Locke
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | | | - Tanmay Sapre
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - Natasha Gozali
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - G Ekin Atilla-Gokcumen
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Shao-En Ong
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - John D Scott
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| | - Raymond S Yeung
- Department of Surgery, University of Washington Medical Center, Seattle, WA, United States
| | - Yasemin Sancak
- Department of Pharmacology, University of Washington, Seattle, WA, United States
| |
Collapse
|
2
|
Khang AR, Kim DH, Kim MJ, Oh CJ, Jeon JH, Choi SH, Lee IK. Reducing Oxidative Stress and Inflammation by Pyruvate Dehydrogenase Kinase 4 Inhibition Is Important in Prevention of Renal Ischemia-Reperfusion Injury in Diabetic Mice. Diabetes Metab J 2024; 48:405-417. [PMID: 38311057 PMCID: PMC11140394 DOI: 10.4093/dmj.2023.0196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 07/13/2023] [Indexed: 02/06/2024] Open
Abstract
BACKGRUOUND Reactive oxygen species (ROS) and inflammation are reported to have a fundamental role in the pathogenesis of ischemia-reperfusion (IR) injury, a leading cause of acute kidney injury. The present study investigated the role of pyruvate dehydrogenase kinase 4 (PDK4) in ROS production and inflammation following IR injury. METHODS We used a streptozotocin-induced diabetic C57BL6/J mouse model, which was subjected to IR by clamping both renal pedicles. Cellular apoptosis and inflammatory markers were evaluated in NRK-52E cells and mouse primary tubular cells after hypoxia and reoxygenation using a hypoxia work station. RESULTS Following IR injury in diabetic mice, the expression of PDK4, rather than the other PDK isoforms, was induced with a marked increase in pyruvate dehydrogenase E1α (PDHE1α) phosphorylation. This was accompanied by a pronounced ROS activation, as well as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and monocyte chemoattractant protein-1 (MCP-1) production. Notably, sodium dichloroacetate (DCA) attenuated renal IR injury-induced apoptosis which can be attributed to reducing PDK4 expression and PDHE1α phosphorylation levels. DCA or shPdk4 treatment reduced oxidative stress and decreased TNF-α, IL-6, IL-1β, and MCP-1 production after IR or hypoxia-reoxygenation injury. CONCLUSION PDK4 inhibition alleviated renal injury with decreased ROS production and inflammation, supporting a critical role for PDK4 in IR mediated damage. This result indicates another potential target for reno-protection during IR injury; accordingly, the role of PDK4 inhibition needs to be comprehensively elucidated in terms of mitochondrial function during renal IR injury.
Collapse
Affiliation(s)
- Ah Reum Khang
- Department of Internal Medicine, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan, Korea
| | - Dong Hun Kim
- Department of Biomedical Science, Graduate School, Kyungpook National University, Daegu, Korea
| | - Min-Ji Kim
- Department of Internal Medicine, Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Chang Joo Oh
- Research Institute of Aging and Metabolism, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Jae-Han Jeon
- Department of Internal Medicine, Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
- Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Korea
| | - Sung Hee Choi
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - In-Kyu Lee
- Research Institute of Aging and Metabolism, School of Medicine, Kyungpook National University, Daegu, Korea
- Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Korea
- Department of Internal Medicine, Kyungpook National University Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
| |
Collapse
|
3
|
Hansen FM, Kremer LS, Karayel O, Bludau I, Larsson NG, Kühl I, Mann M. Mitochondrial phosphoproteomes are functionally specialized across tissues. Life Sci Alliance 2024; 7:e202302147. [PMID: 37984987 PMCID: PMC10662294 DOI: 10.26508/lsa.202302147] [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: 05/09/2023] [Revised: 11/03/2023] [Accepted: 11/07/2023] [Indexed: 11/22/2023] Open
Abstract
Mitochondria are essential organelles whose dysfunction causes human pathologies that often manifest in a tissue-specific manner. Accordingly, mitochondrial fitness depends on versatile proteomes specialized to meet diverse tissue-specific requirements. Increasing evidence suggests that phosphorylation may play an important role in regulating tissue-specific mitochondrial functions and pathophysiology. Building on recent advances in mass spectrometry (MS)-based proteomics, we here quantitatively profile mitochondrial tissue proteomes along with their matching phosphoproteomes. We isolated mitochondria from mouse heart, skeletal muscle, brown adipose tissue, kidney, liver, brain, and spleen by differential centrifugation followed by separation on Percoll gradients and performed high-resolution MS analysis of the proteomes and phosphoproteomes. This in-depth map substantially quantifies known and predicted mitochondrial proteins and provides a resource of core and tissue-specific mitochondrial proteins (mitophos.de). Predicting kinase substrate associations for different mitochondrial compartments indicates tissue-specific regulation at the phosphoproteome level. Illustrating the functional value of our resource, we reproduce mitochondrial phosphorylation events on dynamin-related protein 1 responsible for its mitochondrial recruitment and fission initiation and describe phosphorylation clusters on MIGA2 linked to mitochondrial fusion.
Collapse
Affiliation(s)
- Fynn M Hansen
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Laura S Kremer
- https://ror.org/056d84691 Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Ozge Karayel
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Isabell Bludau
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Nils-Göran Larsson
- https://ror.org/056d84691 Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Inge Kühl
- Department of Cell Biology, Institute of Integrative Biology of the Cell, UMR9198, CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Matthias Mann
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| |
Collapse
|
4
|
Szabo E, Nagy B, Czajlik A, Komlodi T, Ozohanics O, Tretter L, Ambrus A. Mitochondrial Alpha-Keto Acid Dehydrogenase Complexes: Recent Developments on Structure and Function in Health and Disease. Subcell Biochem 2024; 104:295-381. [PMID: 38963492 DOI: 10.1007/978-3-031-58843-3_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
The present work delves into the enigmatic world of mitochondrial alpha-keto acid dehydrogenase complexes discussing their metabolic significance, enzymatic operation, moonlighting activities, and pathological relevance with links to underlying structural features. This ubiquitous family of related but diverse multienzyme complexes is involved in carbohydrate metabolism (pyruvate dehydrogenase complex), the citric acid cycle (α-ketoglutarate dehydrogenase complex), and amino acid catabolism (branched-chain α-keto acid dehydrogenase complex, α-ketoadipate dehydrogenase complex); the complexes all function at strategic points and also participate in regulation in these metabolic pathways. These systems are among the largest multienzyme complexes with at times more than 100 protein chains and weights ranging up to ~10 million Daltons. Our chapter offers a wealth of up-to-date information on these multienzyme complexes for a comprehensive understanding of their significance in health and disease.
Collapse
Affiliation(s)
- Eszter Szabo
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Balint Nagy
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Andras Czajlik
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Timea Komlodi
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Oliver Ozohanics
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Laszlo Tretter
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Attila Ambrus
- Department of Biochemistry, Semmelweis University, Budapest, Hungary.
| |
Collapse
|
5
|
Li C, Liu C, Zhang J, Lu Y, Jiang B, Xiong H, Li C. Pyruvate dehydrogenase kinase regulates macrophage polarization in metabolic and inflammatory diseases. Front Immunol 2023; 14:1296687. [PMID: 38193078 PMCID: PMC10773690 DOI: 10.3389/fimmu.2023.1296687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 11/13/2023] [Indexed: 01/10/2024] Open
Abstract
Macrophages are highly heterogeneous and plastic, and have two main polarized phenotypes that are determined by their microenvironment, namely pro- and anti-inflammatory macrophages. Activation of pro-inflammatory macrophages is closely associated with metabolic reprogramming, especially that of aerobic glycolysis. Mitochondrial pyruvate dehydrogenase kinase (PDK) negatively regulates pyruvate dehydrogenase complex activity through reversible phosphorylation and further links glycolysis to the tricarboxylic acid cycle and ATP production. PDK is commonly associated with the metabolism and polarization of macrophages in metabolic and inflammatory diseases. This review examines the relationship between PDK and macrophage metabolism and discusses the mechanisms by which PDK regulates macrophage polarization, migration, and inflammatory cytokine secretion in metabolic and inflammatory diseases. Elucidating the relationships between the metabolism and polarization of macrophages under physiological and pathological conditions, as well as the regulatory pathways involved, may provide valuable insights into the etiology and treatment of macrophage-mediated inflammatory diseases.
Collapse
Affiliation(s)
- Chenyu Li
- Institute of Immunology and Molecular Medicine, Jining Medical University, Jining, Shandong, China
| | - Chuanbin Liu
- Department of Pediatric Dentistry, Jining Stomatological Hospital, Jining, Shandong, China
| | - Junfeng Zhang
- Institute of Immunology and Molecular Medicine, Jining Medical University, Jining, Shandong, China
| | - Yanyu Lu
- Institute of Immunology and Molecular Medicine, Jining Medical University, Jining, Shandong, China
| | - Bingtong Jiang
- Institute of Immunology and Molecular Medicine, Jining Medical University, Jining, Shandong, China
| | - Huabao Xiong
- Institute of Immunology and Molecular Medicine, Jining Medical University, Jining, Shandong, China
| | - Chunxia Li
- Institute of Immunology and Molecular Medicine, Jining Medical University, Jining, Shandong, China
| |
Collapse
|
6
|
Chen M, Chen Y, Zhu W, Yan X, Xiao J, Zhang P, Liu P, Li P. Advances in the pharmacological study of Chinese herbal medicine to alleviate diabetic nephropathy by improving mitochondrial oxidative stress. Biomed Pharmacother 2023; 165:115088. [PMID: 37413900 DOI: 10.1016/j.biopha.2023.115088] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/25/2023] [Accepted: 06/26/2023] [Indexed: 07/08/2023] Open
Abstract
Diabetic nephropathy (DN) is one of the serious complications of diabetes mellitus, primarily arising from type 2 diabetes (T2DM), and can progress to chronic kidney disease (CKD) and end stage renal disease (ESRD). The pathogenesis of DN involves various factors such as hemodynamic changes, oxidative stress, inflammatory response, and lipid metabolism disorders. Increasing attention is being given to DN caused by oxidative stress in the mitochondrial pathway, prompting researchers to explore drugs that can regulate these target pathways. Chinese herbal medicine, known for its accessibility, rich historical usage, and remarkable efficacy, has shown promise in ameliorating renal injury caused by DN by modulating oxidative stress in the mitochondrial pathway. This review aims to provide a reference for the prevention and treatment of DN. Firstly, we outline the mechanisms by which mitochondrial dysfunction impairs DN, focusing on outlining the damage to mitochondria by oxidative stress. Subsequently, we describe the process by which formulas, herbs and monomeric compounds protect the kidney by ameliorating oxidative stress in the mitochondrial pathway. Finally, the rich variety of Chinese herbal medicine, combined with modern extraction techniques, has great potential, and as we gradually understand the pathogenesis of DN and research techniques are constantly updated, there will be more and more promising therapeutic targets and herbal drug candidates. This paper aims to provide a reference for the prevention and treatment of DN.
Collapse
Affiliation(s)
- Ming Chen
- Renal Division, Department of Medicine, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Yao Chen
- Renal Division, Department of Medicine, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Wenhui Zhu
- Renal Division, Department of Medicine, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Xiaoming Yan
- Renal Division, Department of Medicine, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Jing Xiao
- Renal Division, Department of Medicine, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Peiqing Zhang
- Renal Division, Department of Medicine, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China.
| | - Peng Liu
- Shunyi Hospital, Beijing Hospital of Traditional Chinese Medicine, Beijing, China.
| | - Ping Li
- Beijing Key Lab for Immune-Mediated Inflammatory Diseases, China-Japan Friendship Hospital, Beijing, China.
| |
Collapse
|
7
|
Bunik V. The Therapeutic Potential of Vitamins B1, B3 and B6 in Charcot-Marie-Tooth Disease with the Compromised Status of Vitamin-Dependent Processes. BIOLOGY 2023; 12:897. [PMID: 37508330 PMCID: PMC10376249 DOI: 10.3390/biology12070897] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/11/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023]
Abstract
Understanding the molecular mechanisms of neurological disorders is necessary for the development of personalized medicine. When the diagnosis considers not only the disease symptoms, but also their molecular basis, treatments tailored to individual patients may be suggested. Vitamin-responsive neurological disorders are induced by deficiencies in vitamin-dependent processes. These deficiencies may occur due to genetic impairments of proteins whose functions are involved with the vitamins. This review considers the enzymes encoded by the DHTKD1, PDK3 and PDXK genes, whose mutations are observed in patients with Charcot-Marie-Tooth (CMT) disease. The enzymes bind or produce the coenzyme forms of vitamins B1 (thiamine diphosphate, ThDP) and B6 (pyridoxal-5'-phosphate, PLP). Alleviation of such disorders through administration of the lacking vitamin or its derivative calls for a better introduction of mechanistic knowledge to medical diagnostics and therapies. Recent data on lower levels of the vitamin B3 derivative, NAD+, in the blood of patients with CMT disease vs. control subjects are also considered in view of the NAD-dependent mechanisms of pathological axonal degeneration, suggesting the therapeutic potential of vitamin B3 in these patients. Thus, improved diagnostics of the underlying causes of CMT disease may allow patients with vitamin-responsive disease forms to benefit from the administration of the vitamins B1, B3, B6, their natural derivatives, or their pharmacological forms.
Collapse
Affiliation(s)
- Victoria Bunik
- Belozersky Institute of Physicochemical Biology, Department of Biokinetics, Lomonosov Moscow State University, 119234 Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119234 Moscow, Russia
- Department of Biochemistry, Sechenov University, 119048 Moscow, Russia
| |
Collapse
|
8
|
Liu Y, Dantas E, Ferrer M, Liu Y, Comjean A, Davidson EE, Hu Y, Goncalves MD, Janowitz T, Perrimon N. Tumor Cytokine-Induced Hepatic Gluconeogenesis Contributes to Cancer Cachexia: Insights from Full Body Single Nuclei Sequencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.15.540823. [PMID: 37292804 PMCID: PMC10245574 DOI: 10.1101/2023.05.15.540823] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A primary cause of death in cancer patients is cachexia, a wasting syndrome attributed to tumor-induced metabolic dysregulation. Despite the major impact of cachexia on the treatment, quality of life, and survival of cancer patients, relatively little is known about the underlying pathogenic mechanisms. Hyperglycemia detected in glucose tolerance test is one of the earliest metabolic abnormalities observed in cancer patients; however, the pathogenesis by which tumors influence blood sugar levels remains poorly understood. Here, utilizing a Drosophila model, we demonstrate that the tumor secreted interleukin-like cytokine Upd3 induces fat body expression of Pepck1 and Pdk, two key regulatory enzymes of gluconeogenesis, contributing to hyperglycemia. Our data further indicate a conserved regulation of these genes by IL-6/JAK-STAT signaling in mouse models. Importantly, in both fly and mouse cancer cachexia models, elevated gluconeogenesis gene levels are associated with poor prognosis. Altogether, our study uncovers a conserved role of Upd3/IL-6/JAK-STAT signaling in inducing tumor-associated hyperglycemia, which provides insights into the pathogenesis of IL-6 signaling in cancer cachexia.
Collapse
Affiliation(s)
- Ying Liu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Ezequiel Dantas
- Division of Endocrinology, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
- Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Miriam Ferrer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY 11724 USA
| | - Yifang Liu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Aram Comjean
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Emma E. Davidson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY 11724 USA
| | - Yanhui Hu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Marcus D. Goncalves
- Division of Endocrinology, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
- Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Tobias Janowitz
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY 11724 USA
- Northwell Health Cancer Institute, Northwell Health, New Hyde Park, New York, NY 11042 USA
| | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Harvard University, Boston, MA 02115, USA
- Howard Hughes Medical Institute, Boston, MA, USA
| |
Collapse
|
9
|
Pecoraro C, De Franco M, Carbone D, Bassani D, Pavan M, Cascioferro S, Parrino B, Cirrincione G, Dall'Acqua S, Moro S, Gandin V, Diana P. 1,2,4-Amino-triazine derivatives as pyruvate dehydrogenase kinase inhibitors: Synthesis and pharmacological evaluation. Eur J Med Chem 2023; 249:115134. [PMID: 36709650 DOI: 10.1016/j.ejmech.2023.115134] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/08/2023] [Accepted: 01/16/2023] [Indexed: 01/25/2023]
Abstract
Among the different hallmarks of cancer, deregulation of cellular metabolism turned out to be an essential mechanism in promoting cancer resistance and progression. The pyruvate dehydrogenase kinases (PDKs) are well known as key regulators in cells metabolic process and their activity was found to be overexpressed in different metabolic alerted types of cancer, including the high aggressive pancreatic ductal adenocarcinoma (PDAC). To date few PDK inhibitors have been reported, and the different molecules developed are characterized by structural chemical diversity. In an attempt to find novel classes of potential PDK inhibitors, the molecular hybridization approach, which combine two or more active scaffolds in a single structure, was employed. Herein we report the synthesis and the pharmacological evaluation of the novel hybrid molecules, characterized by the fusion of three different pharmacophoric sub-units such as 1,2,4-amino triazines, 7-azaindoles and indoles, in a single structure. The synthesized derivatives demonstrated a promising ability in hampering the enzymatic activity of PDK1 and 4, further confirmed by docking studies. Interestingly, these derivatives retained a strong antiproliferative activity against pancreatic cancer cells either in 2D and 3D models. Mechanistic studies in highly aggressive PDAC cells confirmed their ability to hamper PDK axis and to induce cancer cell death by apoptosis. Moreover, in vivo translational studies in a murine syngeneic solid tumor model confirmed the ability of the most representative compounds to target the PDK system and highlight the ability to reduce the tumor growth without inducing substantial body weight changes in the treated mice.
Collapse
Affiliation(s)
- Camilla Pecoraro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, via Archirafi 32, 90123, Palermo, Italy
| | - Michele De Franco
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, via F. Marzolo 5, 35131, Padova, Italy
| | - Daniela Carbone
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, via Archirafi 32, 90123, Palermo, Italy
| | - Davide Bassani
- Department of Pharmaceutical and Pharmacological Sciences, Molecular Modeling Section (MMS), University of Padova, via F. Marzolo 5, 35131, Padova, Italy
| | - Matteo Pavan
- Department of Pharmaceutical and Pharmacological Sciences, Molecular Modeling Section (MMS), University of Padova, via F. Marzolo 5, 35131, Padova, Italy
| | - Stella Cascioferro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, via Archirafi 32, 90123, Palermo, Italy
| | - Barbara Parrino
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, via Archirafi 32, 90123, Palermo, Italy
| | - Girolamo Cirrincione
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, via Archirafi 32, 90123, Palermo, Italy
| | - Stefano Dall'Acqua
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, via F. Marzolo 5, 35131, Padova, Italy
| | - Stefano Moro
- Department of Pharmaceutical and Pharmacological Sciences, Molecular Modeling Section (MMS), University of Padova, via F. Marzolo 5, 35131, Padova, Italy
| | - Valentina Gandin
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, via F. Marzolo 5, 35131, Padova, Italy.
| | - Patrizia Diana
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, via Archirafi 32, 90123, Palermo, Italy.
| |
Collapse
|
10
|
Meyers AK, Wang Z, Han W, Zhao Q, Zabalawi M, Duan L, Liu J, Zhang Q, Manne RK, Lorenzo F, Quinn MA, Song Q, Fan D, Lin HK, Furdui CM, Locasale JW, McCall CE, Zhu X. Pyruvate dehydrogenase kinase supports macrophage NLRP3 inflammasome activation during acute inflammation. Cell Rep 2023; 42:111941. [PMID: 36640341 PMCID: PMC10117036 DOI: 10.1016/j.celrep.2022.111941] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 08/02/2022] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
Activating the macrophage NLRP3 inflammasome can promote excessive inflammation with severe cell and tissue damage and organ dysfunction. Here, we show that pharmacological or genetic inhibition of pyruvate dehydrogenase kinase (PDHK) significantly attenuates NLRP3 inflammasome activation in murine and human macrophages and septic mice by lowering caspase-1 cleavage and interleukin-1β (IL-1β) secretion. Inhibiting PDHK reverses NLRP3 inflammasome-induced metabolic reprogramming, enhances autophagy, promotes mitochondrial fusion over fission, preserves crista ultrastructure, and attenuates mitochondrial reactive oxygen species (ROS) production. The suppressive effect of PDHK inhibition on the NLRP3 inflammasome is independent of its canonical role as a pyruvate dehydrogenase regulator. Our study suggestsa non-canonical role of mitochondrial PDHK in promoting mitochondrial stress and supporting NLRP3 inflammasome activation during acute inflammation.
Collapse
Affiliation(s)
- Allison K Meyers
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Zhan Wang
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Wenzheng Han
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA; Department of Cardiology, Huadong Hospital Affiliated to Fudan University, Shanghai 200040, China
| | - Qingxia Zhao
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Manal Zabalawi
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Likun Duan
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Juan Liu
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Qianyi Zhang
- Department of Biology, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Rajesh K Manne
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Felipe Lorenzo
- Section on Endocrinology and Metabolism, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Matthew A Quinn
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Qianqian Song
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Daping Fan
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29209, USA
| | - Hui-Kuan Lin
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Cristina M Furdui
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Jason W Locasale
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Charles E McCall
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA; Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Xuewei Zhu
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA; Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
| |
Collapse
|
11
|
Liu P, Chen Y, Xiao J, Zhu W, Yan X, Chen M. Protective effect of natural products in the metabolic-associated kidney diseases via regulating mitochondrial dysfunction. Front Pharmacol 2023; 13:1093397. [PMID: 36712696 PMCID: PMC9877617 DOI: 10.3389/fphar.2022.1093397] [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: 11/09/2022] [Accepted: 12/28/2022] [Indexed: 01/13/2023] Open
Abstract
Metabolic syndrome (MS) is a complex group of metabolic disorders syndrome with hypertension, hyperuricemia and disorders of glucose or lipid metabolism. As an important organ involved in metabolism, the kidney is inevitably attacked by various metabolic disorders, leading to abnormalities in kidney structure and function. Recently, an increasing number of studies have shown that mitochondrial dysfunction is actively involved in the development of metabolic-associated kidney diseases. Mitochondrial dysfunction can be used as a potential therapeutic strategy for the treatment of metabolic-associated kidney diseases. Many natural products have been widely used to improve the treatment of metabolic-associated kidney diseases by inhibiting mitochondrial dysfunction. In this paper, by searching several authoritative databases such as PubMed, Web of Science, Wiley Online Library, and Springer Link. We summarize the Natural Products Protect Against Metabolic-Associated Kidney Diseases by Regulating Mitochondrial Dysfunction. In this review, we sought to provide an overview of the mechanisms by which mitochondrial dysfunction impaired metabolic-associated kidney diseases, with particular attention to the role of mitochondrial dysfunction in diabetic nephropathy, gouty nephropathy, hypertensive kidney disease, and obesity-related nephropathy, and then the protective role of natural products in the kidney through inhibition of mitochondrial disorders, thus providing a systematic understanding of the targets of mitochondrial dysfunction in metabolic-associated kidney diseases, and finally a review of promising therapeutic targets and herbal candidates for metabolic-associated kidney diseases through inhibition of mitochondrial dysfunction.
Collapse
Affiliation(s)
- Peng Liu
- Shunyi Hospital, Beijing Traditional Chinese Medicine Hospital, Beijing, China
| | - Yao Chen
- Department of Medicine, Renal Division, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Jing Xiao
- Department of Medicine, Renal Division, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Wenhui Zhu
- Department of Medicine, Renal Division, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Xiaoming Yan
- Department of Medicine, Digestive Division, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| | - Ming Chen
- Department of Medicine, Renal Division, Heilongjiang Academy of Chinese Medicine Sciences, Harbin, China
| |
Collapse
|
12
|
Arnold PK, Finley LW. Regulation and function of the mammalian tricarboxylic acid cycle. J Biol Chem 2022; 299:102838. [PMID: 36581208 PMCID: PMC9871338 DOI: 10.1016/j.jbc.2022.102838] [Citation(s) in RCA: 58] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 12/15/2022] [Accepted: 12/20/2022] [Indexed: 12/27/2022] Open
Abstract
The tricarboxylic acid (TCA) cycle, otherwise known as the Krebs cycle, is a central metabolic pathway that performs the essential function of oxidizing nutrients to support cellular bioenergetics. More recently, it has become evident that TCA cycle behavior is dynamic, and products of the TCA cycle can be co-opted in cancer and other pathologic states. In this review, we revisit the TCA cycle, including its potential origins and the history of its discovery. We provide a detailed accounting of the requirements for sustained TCA cycle function and the critical regulatory nodes that can stimulate or constrain TCA cycle activity. We also discuss recent advances in our understanding of the flexibility of TCA cycle wiring and the increasingly appreciated heterogeneity in TCA cycle activity exhibited by mammalian cells. Deeper insight into how the TCA cycle can be differentially regulated and, consequently, configured in different contexts will shed light on how this pathway is primed to meet the requirements of distinct mammalian cell states.
Collapse
Affiliation(s)
- Paige K. Arnold
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York, USA,Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Lydia W.S. Finley
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York, USA,For correspondence: Lydia W. S. Finley
| |
Collapse
|
13
|
Luo Y, Zhou W, Li R, Limbu SM, Qiao F, Chen L, Zhang M, Du ZY. Inhibition of pyruvate dehydrogenase kinase improves carbohydrate utilization in Nile tilapia by regulating PDK2/4-PDHE1α axis and insulin sensitivity. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2022; 11:25-37. [PMID: 36016966 PMCID: PMC9382415 DOI: 10.1016/j.aninu.2022.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 05/05/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
Pyruvate dehydrogenase kinases (PDKs)-pyruvate dehydrogenase E1α subunit (PDHE1α) axis plays an important role in regulating glucose metabolism in mammals. However, the regulatory function of PDKs-PDHE1α axis in the glucose metabolism of fish is not well known. This study determined whether PDKs inhibition could enhance PDHE1α activity, and improve glucose catabolism in fish. Nile tilapia fingerlings (1.90 ± 0.11 g) were randomly divided into 4 treatments in triplicate (30 fish each) and fed control diet without dichloroacetate (DCA) (38% protein, 7% lipid and 45% corn starch) and the control diet supplemented with DCA, which inhibits PDKs through binding the allosteric sites, at 3.75 (DCA3.75), 7.50 (DCA7.50) and 11.25 g/kg (DCA11.25), for 6 wk. The results showed that DCA3.75, DCA7.50 and DCA11.25 significantly increased weight gain, carcass ratio and protein efficiency ratio (P < 0.05) and reduced feed efficiency (P < 0.05) of Nile tilapia. To investigate the effects of DCA on growth performance of Nile tilapia, we selected the lowest dose DCA3.75 for subsequent analysis. Nile tilapia fed on DCA3.75 significantly reduced the mesenteric fat index, serum and liver triglyceride concentration and total lipid content in whole fish, and down-regulated the expressions of genes related to lipogenesis (P < 0.05) compared to the control. The DCA3.75 treatment significantly improved glucose oxidative catabolism and glycogen synthesis in the liver, but significantly reduced the conversion of glucose to lipid (P < 0.05). Furthermore, the DCA3.75 treatment significantly decreased the PDK2/4 gene and protein expressions (P < 0.05), accordingly stimulated PDHE1α activity by decreasing the phosphorylated PDHE1α protein level. In addition, DCA3.75 treatment significantly increased the phosphorylated levels of key proteins involved in insulin signaling pathway and glycogen synthase kinase 3β (P < 0.05). Taken together, the present study demonstrates that PDK2/4 inhibition by using DCA promotes glucose utilization in Nile tilapia by activating PDHE1α and improving insulin sensitivity. Our study helps to understand the regulatory mechanism of glucose metabolism for improving dietary carbohydrate utilization in farmed fish.
Collapse
Affiliation(s)
- Yuan Luo
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Wenhao Zhou
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Ruixin Li
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Samwel M. Limbu
- University of Dar Es Salaam, Department of Aquaculture Technology, Dar Es Salaam 60091, Tanzania
- UDSM-ECNU Joint Research Center for Aquaculture and Fish Biology (JRCAFB), Dar Es Salaam 60091, Tanzania
| | - Fang Qiao
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Liqiao Chen
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Meiling Zhang
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Zhen-Yu Du
- LANEH, School of Life Sciences, East China Normal University, Shanghai 200241, China
- ECNU-UDSM Joint Research Center for Aquaculture and Fish Biology (JRCAFB), Shanghai 200241, China
| |
Collapse
|
14
|
Park S, Mossmann D, Chen Q, Wang X, Dazert E, Colombi M, Schmidt A, Ryback B, Ng CKY, Terracciano LM, Heim MH, Hall MN. Transcription factors TEAD2 and E2A globally repress acetyl-CoA synthesis to promote tumorigenesis. Mol Cell 2022; 82:4246-4261.e11. [PMID: 36400009 DOI: 10.1016/j.molcel.2022.10.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 08/22/2022] [Accepted: 10/24/2022] [Indexed: 11/18/2022]
Abstract
Acetyl-coenzyme A (acetyl-CoA) plays an important role in metabolism, gene expression, signaling, and other cellular processes via transfer of its acetyl group to proteins and metabolites. However, the synthesis and usage of acetyl-CoA in disease states such as cancer are poorly characterized. Here, we investigated global acetyl-CoA synthesis and protein acetylation in a mouse model and patient samples of hepatocellular carcinoma (HCC). Unexpectedly, we found that acetyl-CoA levels are decreased in HCC due to transcriptional downregulation of all six acetyl-CoA biosynthesis pathways. This led to hypo-acetylation specifically of non-histone proteins, including many enzymes in metabolic pathways. Importantly, repression of acetyl-CoA synthesis promoted oncogenic dedifferentiation and proliferation. Mechanistically, acetyl-CoA synthesis was repressed by the transcription factors TEAD2 and E2A, previously unknown to control acetyl-CoA synthesis. Knockdown of TEAD2 and E2A restored acetyl-CoA levels and inhibited tumor growth. Our findings causally link transcriptional reprogramming of acetyl-CoA metabolism, dedifferentiation, and cancer.
Collapse
Affiliation(s)
- Sujin Park
- Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Dirk Mossmann
- Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Qian Chen
- Department of Biomedicine, University of Basel, 4031 Basel, Switzerland; Division of Gastroenterology and Hepatology, Clarunis, University Center for Gastrointestinal and Liver Diseases, 4031 Basel, Switzerland
| | - Xueya Wang
- Department of Biomedicine, University of Basel, 4031 Basel, Switzerland; Division of Gastroenterology and Hepatology, Clarunis, University Center for Gastrointestinal and Liver Diseases, 4031 Basel, Switzerland
| | - Eva Dazert
- Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Marco Colombi
- Biozentrum, University of Basel, 4056 Basel, Switzerland
| | | | - Brendan Ryback
- Institute of Molecular Systems Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Charlotte K Y Ng
- Institute of Pathology, University Hospital Basel, 4031 Basel, Switzerland; Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | | | - Markus H Heim
- Department of Biomedicine, University of Basel, 4031 Basel, Switzerland; Division of Gastroenterology and Hepatology, Clarunis, University Center for Gastrointestinal and Liver Diseases, 4031 Basel, Switzerland
| | - Michael N Hall
- Biozentrum, University of Basel, 4056 Basel, Switzerland.
| |
Collapse
|
15
|
Metabolic and Cellular Compartments of Acetyl-CoA in the Healthy and Diseased Brain. Int J Mol Sci 2022; 23:ijms231710073. [PMID: 36077475 PMCID: PMC9456256 DOI: 10.3390/ijms231710073] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/29/2022] [Accepted: 08/31/2022] [Indexed: 11/25/2022] Open
Abstract
The human brain is characterised by the most diverse morphological, metabolic and functional structure among all body tissues. This is due to the existence of diverse neurons secreting various neurotransmitters and mutually modulating their own activity through thousands of pre- and postsynaptic interconnections in each neuron. Astroglial, microglial and oligodendroglial cells and neurons reciprocally regulate the metabolism of key energy substrates, thereby exerting several neuroprotective, neurotoxic and regulatory effects on neuronal viability and neurotransmitter functions. Maintenance of the pool of mitochondrial acetyl-CoA derived from glycolytic glucose metabolism is a key factor for neuronal survival. Thus, acetyl-CoA is regarded as a direct energy precursor through the TCA cycle and respiratory chain, thereby affecting brain cell viability. It is also used for hundreds of acetylation reactions, including N-acetyl aspartate synthesis in neuronal mitochondria, acetylcholine synthesis in cholinergic neurons, as well as divergent acetylations of several proteins, peptides, histones and low-molecular-weight species in all cellular compartments. Therefore, acetyl-CoA should be considered as the central point of metabolism maintaining equilibrium between anabolic and catabolic pathways in the brain. This review presents data supporting this thesis.
Collapse
|
16
|
Holloway C, Zhong G, Kim YK, Ye H, Sampath H, Hammerling U, Isoherranen N, Quadro L. Retinoic acid regulates pyruvate dehydrogenase kinase 4 (Pdk4) to modulate fuel utilization in the adult heart: Insights from wild-type and β-carotene 9',10' oxygenase knockout mice. FASEB J 2022; 36:e22513. [PMID: 36004605 PMCID: PMC9544431 DOI: 10.1096/fj.202101910rr] [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: 12/15/2021] [Revised: 08/05/2022] [Accepted: 08/11/2022] [Indexed: 11/11/2022]
Abstract
Regulation of the pyruvate dehydrogenase (PDH) complex by the pyruvate dehydrogenase kinase PDK4 enables the heart to respond to fluctuations in energy demands and substrate availability. Retinoic acid, the transcriptionally active form of vitamin A, is known to be involved in the regulation of cardiac function and growth during embryogenesis as well as under pathological conditions. Whether retinoic acid also maintains cardiac health under physiological conditions is unknown. However, vitamin A status and intake of its carotenoid precursor β-carotene have been linked to the prevention of heart diseases. Here, we provide in vitro and in vivo evidence that retinoic acid regulates cardiac Pdk4 expression and thus PDH activity. Furthermore, we show that mice lacking β-carotene 9',10'-oxygenase (BCO2), the only enzyme of the adult heart that cleaves β-carotene to generate retinoids (vitamin A and its derivatives), displayed cardiac retinoic acid insufficiency and impaired metabolic flexibility linked to a compromised PDK4/PDH pathway. These findings provide novel insights into the functions of retinoic acid in regulating energy metabolism in adult tissues, especially the heart.
Collapse
Affiliation(s)
- Chelsee Holloway
- Graduate Program in Endocrinology and Animal Bioscience, Rutgers University, New Brunswick, New Jersey, USA.,Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA.,Rutgers Center for Lipid Research and Institute of Food Nutrition and Health, Rutgers University, New Brunswick, New Jersey, USA
| | - Guo Zhong
- Department of Pharmaceutics Health Sciences, University of Washington, Seattle, Washington, USA
| | - Youn-Kyung Kim
- Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA.,Rutgers Center for Lipid Research and Institute of Food Nutrition and Health, Rutgers University, New Brunswick, New Jersey, USA
| | - Hong Ye
- Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA.,Rutgers Center for Lipid Research and Institute of Food Nutrition and Health, Rutgers University, New Brunswick, New Jersey, USA.,Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Harini Sampath
- Rutgers Center for Lipid Research and Institute of Food Nutrition and Health, Rutgers University, New Brunswick, New Jersey, USA.,Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Ulrich Hammerling
- Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA.,Rutgers Center for Lipid Research and Institute of Food Nutrition and Health, Rutgers University, New Brunswick, New Jersey, USA
| | - Nina Isoherranen
- Department of Pharmaceutics Health Sciences, University of Washington, Seattle, Washington, USA
| | - Loredana Quadro
- Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA.,Rutgers Center for Lipid Research and Institute of Food Nutrition and Health, Rutgers University, New Brunswick, New Jersey, USA
| |
Collapse
|
17
|
Green SR, Al-Attar R, McKechnie AE, Naidoo S, Storey KB. Phosphorylation status of pyruvate dehydrogenase in the mousebird Colius striatus undergoing torpor. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:337-345. [PMID: 34951526 DOI: 10.1002/jez.2570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 12/07/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
Torpor is a heterothermic response that occurs in some animals to reduce metabolic expenditure. The speckled mousebird (Colius striatus) belongs to one of the few avian taxa possessing the capacity for pronounced torpor, entering a hypometabolic state with concomitant decreases in body temperature in response to reduced food access or elevated thermoregulatory energy requirements. The pyruvate dehydrogenase complex (PDC) is a crucial site regulating metabolism by bridging glycolysis and the Krebs cycle. Three highly conserved phosphorylation sites are found within the E1 enzyme of the complex that inhibit PDC activity and reduce the flow of carbohydrate substrates into the mitochondria. The current study demonstrates a marked increase in S232 phosphorylation during torpor in liver, heart, and skeletal muscle of C. striatus. The increase in S232 phosphorylation during torpor was particularly notable in skeletal muscle where levels were ~49-fold higher in torpid birds compared to controls. This was in contrast to the other two phosphorylation sites (S293 and S300) which remained consistently phosphorylated regardless of tissue. The relevant PDH kinase (PDHK1) known to phosphorylate S232 was found to be substantially upregulated (~5-fold change) in the muscle during torpor as well as increasing moderately in the liver (~2.2-fold increase). Additionally, in the heart, a slight (~23%) decrease in total PDH levels was noted. Taken together the phosphorylation changes in PDH suggest that inhibition of the complex is a common feature across several tissues in the mousebird during torpor and that this regulation is mediated at a specific residue.
Collapse
Affiliation(s)
- Stuart R Green
- Department of Biology, Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
| | - Rasha Al-Attar
- Department of Biology, Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
- McEwen Stem Cell Institute, University Health Network, Toronto, Ontario, Canada
| | - Andrew E McKechnie
- South African Research Chair in Conservation Physiology, South African National Biodiversity Institute, Pretoria, South Africa
- Department of Zoology and Entomology, DSI-NRF Centre of Excellence at the FitzPatrick Institute, University of Pretoria, Hatfield, South Africa
| | - Samantha Naidoo
- Department of Zoology and Entomology, DSI-NRF Centre of Excellence at the FitzPatrick Institute, University of Pretoria, Hatfield, South Africa
| | - Kenneth B Storey
- Department of Biology, Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada
| |
Collapse
|
18
|
Green SR, Storey KB. Functional and post-translational characterization of pyruvate dehydrogenase demonstrates repression of activity in the liver but not skeletal muscle of the Richardson's ground squirrel (Urocitellus richardsonii) during hibernation. J Therm Biol 2021; 99:102996. [PMID: 34420628 DOI: 10.1016/j.jtherbio.2021.102996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/27/2021] [Accepted: 05/11/2021] [Indexed: 10/21/2022]
Abstract
Hibernation consists of a series of physiological and biochemical alterations in an animal that allows for reduced body temperatures down to near ambient levels and substantial fuel conservation allowing it to survive on stored fat supplies accumulated during the summer. The Richardson's ground squirrel is one such hibernator that undergoes such changes for as long as 9 months of the year. This study examines the role of regulation of the pyruvate dehydrogenase complex (PDC) during hibernation in the skeletal muscle and liver of the Richardson's ground squirrel. The current study demonstrates a great reduction in the activity of PDC in the hibernating liver, but not in the skeletal muscle. This was matched by a significant increase in the phosphorylation on a regulatory serine residue (S300) of the pyruvate dehydrogenase (PDH) E1α subunit. Examining the expression patterns of the relevant kinases for PDH and the associated phosphatase demonstrated some unexpected results. Specifically, an increase in PDKs 1 and 2 and a decrease in PDK4 was noted in the skeletal muscle tissue in response to hibernation and no alterations in the expression patterns of any of these enzymes were noted in the liver. This suggests that alternative modes of regulation of the kinases may be at play in hibernation to bring about the observed effects. Taken together this study demonstrates that PDH regulatory responses differ markedly between tissues and emphasize the importance of inhibition of the complex in the liver during hibernation.
Collapse
Affiliation(s)
- Stuart R Green
- Institute of Biochemistry & Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
| | - Kenneth B Storey
- Institute of Biochemistry & Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada.
| |
Collapse
|
19
|
Rahim M, Hasenour CM, Bednarski TK, Hughey CC, Wasserman DH, Young JD. Multitissue 2H/13C flux analysis reveals reciprocal upregulation of renal gluconeogenesis in hepatic PEPCK-C-knockout mice. JCI Insight 2021; 6:e149278. [PMID: 34156032 PMCID: PMC8262479 DOI: 10.1172/jci.insight.149278] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The liver is the major source of glucose production during fasting under normal physiological conditions. However, the kidney may also contribute to maintaining glucose homeostasis in certain circumstances. To test the ability of the kidney to compensate for impaired hepatic glucose production in vivo, we developed a stable isotope approach to simultaneously quantify gluconeogenic and oxidative metabolic fluxes in the liver and kidney. Hepatic gluconeogenesis from phosphoenolpyruvate was disrupted via liver-specific knockout of cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C; KO). 2H/13C isotopes were infused in fasted KO and WT littermate mice, and fluxes were estimated from isotopic measurements of tissue and plasma metabolites using a multicompartment metabolic model. Hepatic gluconeogenesis and glucose production were reduced in KO mice, yet whole-body glucose production and arterial glucose were unaffected. Glucose homeostasis was maintained by a compensatory rise in renal glucose production and gluconeogenesis. Renal oxidative metabolic fluxes of KO mice increased to sustain the energetic and metabolic demands of elevated gluconeogenesis. These results show the reciprocity of the liver and kidney in maintaining glucose homeostasis by coordinated regulation of gluconeogenic flux through PEPCK-C. Combining stable isotopes with mathematical modeling provides a versatile platform to assess multitissue metabolism in various genetic, pathophysiological, physiological, and pharmacological settings.
Collapse
Affiliation(s)
- Mohsin Rahim
- Department of Chemical and Biomolecular Engineering and
| | | | | | - Curtis C Hughey
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - David H Wasserman
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Jamey D Young
- Department of Chemical and Biomolecular Engineering and.,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| |
Collapse
|
20
|
PDK2: An Underappreciated Regulator of Liver Metabolism. LIVERS 2021. [DOI: 10.3390/livers1020008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Pyruvate metabolism is critical for all mammalian cells. The pyruvate dehydrogenase complex couples the pyruvate formed as the primary product of glycolysis to the formation of acetyl-CoA required as the primary substrate of the citric acid cycle. Dysregulation of this coupling contributes to alterations in metabolic flexibility in obesity, diabetes, cancer, and more. The pyruvate dehydrogenase kinase family of isozymes phosphorylate and inactive the pyruvate dehydrogenase complex in the mitochondria. This function makes them critical mediators of mitochondrial metabolism and drug targets in a number of disease states. The liver expresses multiple PDKs, predominantly PDK1 and PDK2 in the fed state and PDK1, PDK2, and PDK4 in the starved and diabetic states. PDK4 undergoes substantial transcriptional regulation in response to a diverse array of stimuli in most tissues. PDK2 has received less attention than PDK4 potentially due to the dramatic changes in transcriptional gene regulation. However, PDK2 is more responsive than the other PDKs to feedforward and feedback regulation by substrates and products of the pyruvate dehydrogenase complex. Although underappreciated, this makes PDK2 particularly important for the minute-to-minute fine control of the pyruvate dehydrogenase complex and a major contributor to metabolic flexibility. The purpose of this review is to characterize the underappreciated role of PDK2 in liver metabolism. We will focus on known biological actions and physiological roles as well as what roles PDK2 may play in disease states. We will also define current inhibitors and address their potential as therapeutic agents in the future.
Collapse
|
21
|
Mainali R, Zabalawi M, Long D, Buechler N, Quillen E, Key CC, Zhu X, Parks JS, Furdui C, Stacpoole PW, Martinez J, McCall CE, Quinn MA. Dichloroacetate reverses sepsis-induced hepatic metabolic dysfunction. eLife 2021; 10:64611. [PMID: 33616039 PMCID: PMC7901874 DOI: 10.7554/elife.64611] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/17/2021] [Indexed: 12/14/2022] Open
Abstract
Metabolic reprogramming between resistance and tolerance occurs within the immune system in response to sepsis. While metabolic tissues such as the liver are subjected to damage during sepsis, how their metabolic and energy reprogramming ensures survival is unclear. Employing comprehensive metabolomic, lipidomic, and transcriptional profiling in a mouse model of sepsis, we show that hepatocyte lipid metabolism, mitochondrial tricarboxylic acid (TCA) energetics, and redox balance are significantly reprogrammed after cecal ligation and puncture (CLP). We identify increases in TCA cycle metabolites citrate, cis-aconitate, and itaconate with reduced fumarate and triglyceride accumulation in septic hepatocytes. Transcriptomic analysis of liver tissue supports and extends the hepatocyte findings. Strikingly, the administration of the pyruvate dehydrogenase kinase (PDK) inhibitor dichloroacetate reverses dysregulated hepatocyte metabolism and mitochondrial dysfunction. In summary, our data indicate that sepsis promotes hepatic metabolic dysfunction and that targeting the mitochondrial PDC/PDK energy homeostat rebalances transcriptional and metabolic manifestations of sepsis within the liver.
Collapse
Affiliation(s)
- Rabina Mainali
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Manal Zabalawi
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - David Long
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Nancy Buechler
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Ellen Quillen
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Chia-Chi Key
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Xuewei Zhu
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - John S Parks
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Cristina Furdui
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Peter W Stacpoole
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine and Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, United States
| | - Jennifer Martinez
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Research Triangle Park, Bethesda, United States
| | - Charles E McCall
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| | - Matthew A Quinn
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, United States.,Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, United States
| |
Collapse
|
22
|
Kyrilis FL, Semchonok DA, Skalidis I, Tüting C, Hamdi F, O'Reilly FJ, Rappsilber J, Kastritis PL. Integrative structure of a 10-megadalton eukaryotic pyruvate dehydrogenase complex from native cell extracts. Cell Rep 2021; 34:108727. [PMID: 33567276 DOI: 10.1016/j.celrep.2021.108727] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 12/02/2020] [Accepted: 01/14/2021] [Indexed: 12/29/2022] Open
Abstract
The pyruvate dehydrogenase complex (PDHc) is a giant enzymatic assembly involved in pyruvate oxidation. PDHc components have been characterized in isolation, but the complex's quaternary structure has remained elusive due to sheer size, heterogeneity, and plasticity. Here, we identify fully assembled Chaetomium thermophilum α-keto acid dehydrogenase complexes in native cell extracts and characterize their domain arrangements utilizing mass spectrometry, activity assays, crosslinking, electron microscopy (EM), and computational modeling. We report the cryo-EM structure of the PDHc core and observe unique features of the previously unknown native state. The asymmetric reconstruction of the 10-MDa PDHc resolves spatial proximity of its components, agrees with stoichiometric data (60 E2p:12 E3BP:∼20 E1p: ≤ 12 E3), and proposes a minimum reaction path among component enzymes. The PDHc shows the presence of a dynamic pyruvate oxidation compartment, organized by core and peripheral protein species. Our data provide a framework for further understanding PDHc and α-keto acid dehydrogenase complex structure and function.
Collapse
Affiliation(s)
- Fotis L Kyrilis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany; Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, Halle/Saale, Germany
| | - Dmitry A Semchonok
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany
| | - Ioannis Skalidis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany; Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, Halle/Saale, Germany
| | - Christian Tüting
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany
| | - Farzad Hamdi
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany
| | - Francis J O'Reilly
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany
| | - Juri Rappsilber
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany; Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, Scotland, United Kingdom
| | - Panagiotis L Kastritis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany; Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, Halle/Saale, Germany; Biozentrum, Martin Luther University Halle-Wittenberg, Weinbergweg 22, Halle/Saale, Germany.
| |
Collapse
|
23
|
Jelinek BA, Moxley MA. Detailed evaluation of pyruvate dehydrogenase complex inhibition in simulated exercise conditions. Biophys J 2021; 120:936-949. [PMID: 33515599 DOI: 10.1016/j.bpj.2021.01.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/31/2020] [Accepted: 01/19/2021] [Indexed: 11/19/2022] Open
Abstract
The mammalian pyruvate dehydrogenase complex (PDC) is a mitochondrial multienzyme complex that connects glycolysis to the tricarboxylic acid cycle by catalyzing pyruvate oxidation to produce acetyl-CoA, NADH, and CO2. This reaction is required to aerobically utilize glucose, a preferred metabolic fuel, and is composed of three core enzymes: pyruvate dehydrogenase (E1), dihydrolipoyl transacetylase (E2), and dihydrolipoyl dehydrogenase (E3). The pyruvate-dehydrogenase-specific kinase (PDK) and pyruvate-dehydrogenase-specific phosphatase (PDP) are considered the main control mechanism of mammalian PDC activity. However, PDK and PDP activity are allosterically regulated by several effectors fully overlapping PDC substrates and products. This collection of positive and negative feedback mechanisms confounds simple predictions of relative PDC flux, especially when all effectors are dynamically modulated during metabolic states that exist in physiologically realistic conditions, such as exercise. Here, we provide, to our knowledge, the first globally fitted, pH-dependent kinetic model of the PDC accounting for the PDC core reaction because it is regulated by PDK, PDP, metal binding equilibria, and numerous allosteric effectors. The model was used to compute PDH regulatory complex flux as a function of previously determined metabolic conditions used to simulate exercise and demonstrates increased flux with exercise. Our model reveals that PDC flux in physiological conditions is primarily inhibited by product inhibition (∼60%), mostly NADH inhibition (∼30-50%), rather than phosphorylation cycle inhibition (∼40%), but the degree to which depends on the metabolic state and PDC tissue source.
Collapse
Affiliation(s)
- Bodhi A Jelinek
- Department of Chemistry, University of Nebraska at Kearney, Kearney, Nebraska
| | - Michael A Moxley
- Department of Chemistry, University of Nebraska at Kearney, Kearney, Nebraska.
| |
Collapse
|
24
|
Atas E, Oberhuber M, Kenner L. The Implications of PDK1-4 on Tumor Energy Metabolism, Aggressiveness and Therapy Resistance. Front Oncol 2020; 10:583217. [PMID: 33384955 PMCID: PMC7771695 DOI: 10.3389/fonc.2020.583217] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 11/13/2020] [Indexed: 12/17/2022] Open
Abstract
A metabolic shift from oxidative phosphorylation (OXPHOS) to glycolysis-known as the Warburg effect-is characteristic for many cancers. It gives the cancer cells a survival advantage in the hypoxic tumor microenvironment and protects them from cytotoxic effects of oxidative damage and apoptosis. The main regulators of this metabolic shift are the pyruvate dehydrogenase complex and pyruvate dehydrogenase kinase (PDK) isoforms 1-4. PDK is known to be overexpressed in several cancers and is associated with bad prognosis and therapy resistance. Whereas the expression of PDK1-3 is tissue specific, PDK4 expression is dependent on the energetic state of the whole organism. In contrast to other PDK isoforms, not only oncogenic, but also tumor suppressive functions of PDK4 have been reported. In tumors that profit from high OXPHOS and high de novo fatty acid synthesis, PDK4 can have a protective effect. This is the case for prostate cancer, the most common cancer in men, and makes PDK4 an interesting therapeutic target. While most work is focused on PDK in tumors characterized by high glycolytic activity, little research is devoted to those cases where PDK4 acts protective and is therefore highly needed.
Collapse
Affiliation(s)
- Emine Atas
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Monika Oberhuber
- Department of Pathology, Medical University of Vienna, Vienna, Austria
- Area ‘Data & Technologies’, CBmed—Center for Biomarker Research in Medicine GmbH, Graz, Austria
| | - Lukas Kenner
- Department of Pathology, Medical University of Vienna, Vienna, Austria
- Area ‘Data & Technologies’, CBmed—Center for Biomarker Research in Medicine GmbH, Graz, Austria
- Unit of Pathology of Laboratory Animals, University of Veterinary Medicine Vienna, Vienna, Austria
- Christian Doppler Laboratory for Applied Metabolomics (CDL AM), Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
25
|
Jeon JH, Thoudam T, Choi EJ, Kim MJ, Harris RA, Lee IK. Loss of metabolic flexibility as a result of overexpression of pyruvate dehydrogenase kinases in muscle, liver and the immune system: Therapeutic targets in metabolic diseases. J Diabetes Investig 2020; 12:21-31. [PMID: 32628351 PMCID: PMC7779278 DOI: 10.1111/jdi.13345] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022] Open
Abstract
Good health depends on the maintenance of metabolic flexibility, which in turn is dependent on the maintenance of regulatory flexibility of a large number of regulatory enzymes, but especially the pyruvate dehydrogenase complex (PDC), because of its central role in carbohydrate metabolism. Flexibility in regulation of PDC is dependent on rapid changes in the phosphorylation state of PDC determined by the relative activities of the pyruvate dehydrogenase kinases (PDKs) and the pyruvate dehydrogenase phosphatases. Inactivation of the PDC by overexpression of PDK4 contributes to hyperglycemia, and therefore the serious health problems associated with diabetes. Loss of regulatory flexibility of PDC occurs in other disease states and pathological conditions that have received less attention than diabetes. These include cancers, non‐alcoholic fatty liver disease, cancer‐induced cachexia, diabetes‐induced nephropathy, sepsis and amyotrophic lateral sclerosis. Overexpression of PDK4, and in some situations, the other PDKs, as well as under expression of the pyruvate dehydrogenase phosphatases, leads to inactivation of the PDC, mitochondrial dysfunction and deleterious effects with health consequences. The possible basis for this phenomenon, along with evidence that overexpression of PDK4 results in phosphorylation of “off‐target” proteins and promotes excessive transport of Ca2+ into mitochondria through mitochondria‐associated endoplasmic reticulum membranes are discussed. Recent efforts to find small molecule PDK inhibitors with therapeutic potential are also reviewed.
Collapse
Affiliation(s)
- Jae-Han Jeon
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Korea.,Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Korea
| | - Themis Thoudam
- Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Korea
| | - Eun Jung Choi
- Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu, Korea
| | - Min-Ji Kim
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Korea
| | - Robert A Harris
- Department of Biochemistry and Molecular Biology, The University of Kansas Medical Center, Kansas City, Kansas, USA
| | - In-Kyu Lee
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Korea.,Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Korea.,Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Korea.,Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu, Korea
| |
Collapse
|
26
|
Kang J, Pagire HS, Kang D, Song YH, Lee IK, Lee KT, Park CJ, Ahn JH, Kim J. Structural basis for the inhibition of PDK2 by novel ATP- and lipoyl-binding site targeting compounds. Biochem Biophys Res Commun 2020; 527:778-784. [PMID: 32444142 DOI: 10.1016/j.bbrc.2020.04.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 04/20/2020] [Indexed: 11/19/2022]
Abstract
Pyruvate dehydrogenase kinase (PDK) controls the activity of pyruvate decarboxylase complex (PDC) by phosphorylating key serine residues on the E1 subunit, which leads to a decreased oxidative phosphorylation in mitochondria. Inhibition of PDK activity by natural/synthetic compounds has been shown to reverse the Warburg effect, a characteristic metabolism in cancer cells. PDK-PDC axis also has been associated with diabetes and heart disease. Therefore, regulation of PDK activity has been considered as a promising strategy to treat related diseases. Here we present the X-ray crystal structure of PDK2 complexed with a recently identified PDK4 inhibitor, compound 8c, which has been predicted to bind at the lipoyl-binding site and interrupt intermolecular interactions with the E2-E3bp subunits of PDC. The co-crystal structure confirmed the specific binding location of compound 8c and revealed the remote conformational change in the ATP-binding pocket. In addition, two novel 4,5-diarylisoxazole derivatives, GM10030 and GM67520, were synthesized and used for structural studies, which target the ATP-binding site of PDK2. These compounds bind to PDK2 with a sub-100nM affinity as determined by isothermal titration calorimetry experiments. Notably, the crystal structure of the PDK2-GM10030 complex displays unprecedented asymmetric conformation of human PDK2 dimer, especially in the ATP-lids and C-terminal tails.
Collapse
Affiliation(s)
- Jihoon Kang
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Haushabhau S Pagire
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Donguk Kang
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Yo Han Song
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - In Kyu Lee
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, 41944, Republic of Korea
| | - Kang Taek Lee
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Chin-Ju Park
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Jin Hee Ahn
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Jungwook Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
| |
Collapse
|
27
|
Expression and prognostic significance of pyruvate dehydrogenase kinase 1 in bladder urothelial carcinoma. Virchows Arch 2020; 477:637-649. [PMID: 32388719 DOI: 10.1007/s00428-020-02782-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 02/17/2020] [Accepted: 02/21/2020] [Indexed: 12/13/2022]
Abstract
Muscular infiltrating bladder urothelial carcinoma (MIBC) is a highly malignant disease with a poor prognosis. Radical cystectomy is the standard treatment. However, due to surgery and postoperative complications, the quality of life of patients is seriously affected. Therefore, it is increasingly important to find prognostic markers and new therapeutic targets for MIBC. Here, we investigated the expression of PDK1, a key regulator of glucose metabolism, in bladder urothelial carcinoma (BLCA) and its effect on prognosis. The expression pattern of PDK1 was examined by bioinformatics analysis and immunohistochemistry. A total of 101 cases of BLCA were selected for tissue microarrays (TMAs) that contained both tumour and paired normal tissues. We demonstrated that PDK1 expression was correlated with tumour grade and Ki67expression in our TMA cohort (all p values < 0.05). Kaplan-Meier survival analysis showed that patients with MIBC with high PDK1 expression had a worse prognosis than patients with low PDK1 expression (p = 0.016). Multifactor risk analysis showed that increased PDK1 expression was an independent prognostic factor affecting the overall survival of MIBC patients. GSEA showed that the mTOR pathway, HIF pathway, glycolysis, PI3K/AKT/mTOR signalling, etc. were differentially enriched in the PDK1 high expression phenotype. Hence, PDK1 may be a prognostic and therapeutic target for MIBC.
Collapse
|
28
|
Lee SJ, Lee IK, Jeon JH. Vascular Calcification-New Insights Into Its Mechanism. Int J Mol Sci 2020; 21:ijms21082685. [PMID: 32294899 PMCID: PMC7216228 DOI: 10.3390/ijms21082685] [Citation(s) in RCA: 196] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/10/2020] [Accepted: 04/10/2020] [Indexed: 02/07/2023] Open
Abstract
Vascular calcification (VC), which is categorized by intimal and medial calcification, depending on the site(s) involved within the vessel, is closely related to cardiovascular disease. Specifically, medial calcification is prevalent in certain medical situations, including chronic kidney disease and diabetes. The past few decades have seen extensive research into VC, revealing that the mechanism of VC is not merely a consequence of a high-phosphorous and -calcium milieu, but also occurs via delicate and well-organized biologic processes, including an imbalance between osteochondrogenic signaling and anticalcific events. In addition to traditionally established osteogenic signaling, dysfunctional calcium homeostasis is prerequisite in the development of VC. Moreover, loss of defensive mechanisms, by microorganelle dysfunction, including hyper-fragmented mitochondria, mitochondrial oxidative stress, defective autophagy or mitophagy, and endoplasmic reticulum (ER) stress, may all contribute to VC. To facilitate the understanding of vascular calcification, across any number of bioscientific disciplines, we provide this review of a detailed updated molecular mechanism of VC. This encompasses a vascular smooth muscle phenotypic of osteogenic differentiation, and multiple signaling pathways of VC induction, including the roles of inflammation and cellular microorganelle genesis.
Collapse
Affiliation(s)
- Sun Joo Lee
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Korea;
| | - In-Kyu Lee
- Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Korea;
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Jae-Han Jeon
- Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Korea;
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea
- Correspondence: ; Tel.: +82-(53)-200-3182; Fax: +82-(53)-200-3155
| |
Collapse
|
29
|
Zhu X, Long D, Zabalawi M, Ingram B, Yoza BK, Stacpoole PW, McCall CE. Stimulating pyruvate dehydrogenase complex reduces itaconate levels and enhances TCA cycle anabolic bioenergetics in acutely inflamed monocytes. J Leukoc Biol 2020; 107:467-484. [PMID: 31894617 DOI: 10.1002/jlb.3a1119-236r] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 11/24/2019] [Accepted: 12/11/2019] [Indexed: 02/06/2023] Open
Abstract
The pyruvate dehydrogenase complex (PDC)/pyruvate dehydrogenase kinase (PDK) axis directs the universal survival principles of immune resistance and tolerance in monocytes by controlling anabolic and catabolic energetics. Immune resistance shifts to immune tolerance during inflammatory shock syndromes when inactivation of PDC by increased PDK activity disrupts the tricarboxylic acid (TCA) cycle support of anabolic pathways. The transition from immune resistance to tolerance also diverts the TCA cycle from citrate-derived cis-aconitate to itaconate, a recently discovered catabolic mediator that separates the TCA cycle at isocitrate and succinate dehydrogenase (SDH). Itaconate inhibits succinate dehydrogenase and its anabolic role in mitochondrial ATP generation. We previously reported that inhibiting PDK in septic mice with dichloroacetate (DCA) increased TCA cycle activity, reversed septic shock, restored innate and adaptive immune and organ function, and increased survival. Here, using unbiased metabolomics in a monocyte culture model of severe acute inflammation that simulates sepsis reprogramming, we show that DCA-induced activation of PDC restored anabolic energetics in inflammatory monocytes while increasing TCA cycle intermediates, decreasing itaconate, and increasing amino acid anaplerotic catabolism of branched-chain amino acids (BCAAs). Our study provides new mechanistic insight that the DCA-stimulated PDC homeostat reconfigures the TCA cycle and promotes anabolic energetics in monocytes by reducing levels of the catabolic mediator itaconate. It further supports the theory that PDC is an energy sensing and signaling homeostat that restores metabolic and energy fitness during acute inflammation.
Collapse
Affiliation(s)
- Xuewei Zhu
- Department of Internal Medicine/Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.,Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - David Long
- Department of Internal Medicine/Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Manal Zabalawi
- Department of Internal Medicine/Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Brian Ingram
- Metabolon, Inc., Morrisville, North Carolina, USA
| | - Barbara K Yoza
- Department of Surgery/General Surgery and Trauma, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Peter W Stacpoole
- Division of Endocrinology, Diabetes & Metabolism, and Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Charles E McCall
- Department of Internal Medicine/Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.,Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| |
Collapse
|
30
|
Atas E, Oberhuber M, Kenner L. The Implications of PDK1-4 on Tumor Energy Metabolism, Aggressiveness and Therapy Resistance. Front Oncol 2020. [PMID: 33384955 DOI: 10.3389/fonc.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
A metabolic shift from oxidative phosphorylation (OXPHOS) to glycolysis-known as the Warburg effect-is characteristic for many cancers. It gives the cancer cells a survival advantage in the hypoxic tumor microenvironment and protects them from cytotoxic effects of oxidative damage and apoptosis. The main regulators of this metabolic shift are the pyruvate dehydrogenase complex and pyruvate dehydrogenase kinase (PDK) isoforms 1-4. PDK is known to be overexpressed in several cancers and is associated with bad prognosis and therapy resistance. Whereas the expression of PDK1-3 is tissue specific, PDK4 expression is dependent on the energetic state of the whole organism. In contrast to other PDK isoforms, not only oncogenic, but also tumor suppressive functions of PDK4 have been reported. In tumors that profit from high OXPHOS and high de novo fatty acid synthesis, PDK4 can have a protective effect. This is the case for prostate cancer, the most common cancer in men, and makes PDK4 an interesting therapeutic target. While most work is focused on PDK in tumors characterized by high glycolytic activity, little research is devoted to those cases where PDK4 acts protective and is therefore highly needed.
Collapse
Affiliation(s)
- Emine Atas
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Monika Oberhuber
- Department of Pathology, Medical University of Vienna, Vienna, Austria
- Area 'Data & Technologies', CBmed-Center for Biomarker Research in Medicine GmbH, Graz, Austria
| | - Lukas Kenner
- Department of Pathology, Medical University of Vienna, Vienna, Austria
- Area 'Data & Technologies', CBmed-Center for Biomarker Research in Medicine GmbH, Graz, Austria
- Unit of Pathology of Laboratory Animals, University of Veterinary Medicine Vienna, Vienna, Austria
- Christian Doppler Laboratory for Applied Metabolomics (CDL AM), Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
31
|
Woolbright BL, Rajendran G, Harris RA, Taylor JA. Metabolic Flexibility in Cancer: Targeting the Pyruvate Dehydrogenase Kinase:Pyruvate Dehydrogenase Axis. Mol Cancer Ther 2019; 18:1673-1681. [PMID: 31511353 DOI: 10.1158/1535-7163.mct-19-0079] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/23/2019] [Accepted: 07/24/2019] [Indexed: 11/16/2022]
Abstract
Cancer cells use alterations of normal metabolic processes to sustain proliferation indefinitely. Transcriptional and posttranscriptional control of the pyruvate dehydrogenase kinase (PDK) family is one way in which cancer cells alter normal pyruvate metabolism to fuel proliferation. PDKs can phosphorylate and inactivate the pyruvate dehydrogenase complex (PDHC), which blocks oxidative metabolism of pyruvate by the mitochondria. This process is thought to enhance cancer cell growth by promoting anabolic pathways. Inhibition of PDKs induces cell death through increased PDH activity and subsequent increases in ROS production. The use of PDK inhibitors has seen widespread success as a potential therapeutic in laboratory models of multiple cancers; however, gaps still exist in our understanding of the biology of PDK regulation and function, especially in the context of individual PDKs. Efforts are currently underway to generate PDK-specific inhibitors and delineate the roles of individual PDK isozymes in specific cancers. The goal of this review is to understand the regulation of the PDK isozyme family, their role in cancer proliferation, and how to target this pathway therapeutically to specifically and effectively reduce cancer growth.
Collapse
Affiliation(s)
| | | | - Robert A Harris
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas
| | - John A Taylor
- Department of Urology, University of Kansas Medical Center, Kansas City, Kansas.
| |
Collapse
|
32
|
Wang Y, Han P, Wang M, Weng W, Zhan H, Yu X, Yuan C, Shao M, Sun H. Artemether improves type 1 diabetic kidney disease by regulating mitochondrial function. Am J Transl Res 2019; 11:3879-3889. [PMID: 31312396 PMCID: PMC6614617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/16/2019] [Indexed: 06/10/2023]
Abstract
Many patients with type 1 diabetes mellitus suffer from progressive diabetic kidney disease (DKD). The progression of DKD is largely attributed to mitochondrial dysfunction, with key contributions from mitochondrial reactive oxygen species. Recent studies have revealed that the antimalarial drug artemether has antidiabetic effects. To identify potential effects on type 1 DKD in the present study, mice with streptozotocin-induced diabetes were treated with artemether. Treatment reduced urinary excretion of albumin and tubular injury biomarkers, increased serum albumin and total protein levels, and attenuated renal hypertrophy. In addition, artemether treatment prevented hyperglycemia, raised serum insulin levels, and restored glucagon/insulin and somatostatin/insulin ratios in islets. We found that artemether improved mitochondrial function and regulated redox balance in kidney. These results demonstrate that artemether provides renal protection in type 1 diabetes mellitus, which may be due to improved mitochondrial function.
Collapse
Affiliation(s)
- Yao Wang
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Pengxun Han
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Menghua Wang
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Wenci Weng
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Hongyue Zhan
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Xuewen Yu
- Department of Pathology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Changjian Yuan
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Mumin Shao
- Department of Pathology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| | - Huili Sun
- Department of Nephrology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033, Guangdong, China
| |
Collapse
|
33
|
A pyruvate dehydrogenase complex disorder hypothesis for bipolar disorder. Med Hypotheses 2019; 130:109263. [PMID: 31383331 DOI: 10.1016/j.mehy.2019.109263] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 05/05/2019] [Accepted: 06/07/2019] [Indexed: 01/15/2023]
Abstract
Ketosis is a metabolic state in which the body uses ketones derived from breakdown of fatty acids as the primary mitochondrial fuel source instead of glucose. In recent years an accumulation of evidence for the beneficial effects of the ketotic state on the brain have heightened interest in its potential for use in neurological conditions. The ketogenic diet (KD) induces ketosis and is an effective treatment for medically resistant epilepsy. There is significant comorbidity between epilepsy and bipolar disorder (BD) and both conditions are treated by anti-convulsant drugs. In addition, reports on bipolar disease online fora have highlighted subjective mood stabilization effects associated with the KD. These KD reported effects could be explained if there was a disorder in the conversion of pyruvate into Acetyl-CoA (and subsequent impairment of oxidative phosphorylation) which was bypassed by ketones providing an alternative substrate for oxidative phosphorylation. This is consistent with growing evidence that mitochondrial dysfunction plays a causal role in BD and explains the reported TCA cycle dysfunction and elevated pyruvate levels in BD. Reduced levels of ATP affects the normal operation of the Na, K-ATPase in the brain with differing levels of reduction either leading to reduced neuronal action potential and inhibition of neurotransmitter release (consistent with the depressed state in BD) or increased neuronal resting potential and hyper-excitability (consistent with a [hypo]manic mood state). We hypothesize that the mitochondrial dysfunction is due to a disorder of the Pyruvate Dehydrogenase Complex (PDC) and/or Mitochondrial Carrier Protein (MCP) shuttle which moves intracellular pyruvate into mitochondria. The resultant reduction in ATP generation could explain mood instability and cycling in BD (through mechanisms such as those delineated by Mallakh and Peters). This proposed novel causal pathway could explain mood de-stabilization in BD and the reported positive effects of KD. If true, this hypothesis would suggest that there should be increased research attention to PDC (and in particular the E1 alpha subunit) as potential therapeutic targets and further study of a possible role of KD in BD to improve mood stability. Experimental approaches, such as through a clinical trial of KD on mood stabilization in BD, are required to further investigate this hypothesis.
Collapse
|
34
|
Veech RL, Todd King M, Pawlosky R, Kashiwaya Y, Bradshaw PC, Curtis W. The "great" controlling nucleotide coenzymes. IUBMB Life 2019; 71:565-579. [PMID: 30624851 PMCID: PMC6850382 DOI: 10.1002/iub.1997] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/04/2018] [Accepted: 12/05/2018] [Indexed: 12/11/2022]
Abstract
Nucleotide coenzymes dot the map of metabolic pathways providing energy to drive the reactions of the pathway and play an important role in regulating and controlling energy metabolism through their shared potential energy, which is widely unobserved due to the paradox that the energy in the coenzyme pools cannot be determined from the concentration of the coenzyme couples. The potential energy of the nucleotide couples in the mitochondria or the cytoplasm is expressed in the enzyme reactions in which they take part. The energy in these couples, [NAD+]/[NADH], [NADP+]/[NADPH], [acetyl CoA]/[CoA], and [ATP]/[ADP]x[Pi], regulates energy metabolism. The energy contained in the couples can be altered by suppling energy equivalents in the form of ketones, such as, D-β-hydroxybutyrate to overcome insulin resistance, to restore antioxidants capacity, to form potential treatments for Alzheimer's and Parkinson's diseases, to enhance life span, and to increase physiological performance. © 2019 IUBMB Life, 71(5):565-579, 2019.
Collapse
Affiliation(s)
- Richard L Veech
- Laboratory of Metabolic Control, NIAAA, NIH, Rockville, MD, 20852, USA
| | - Michael Todd King
- Laboratory of Metabolic Control, NIAAA, NIH, Rockville, MD, 20852, USA
| | - Robert Pawlosky
- Laboratory of Metabolic Control, NIAAA, NIH, Rockville, MD, 20852, USA
| | | | - Patrick C Bradshaw
- Department of Biomedical Sciences, East Tennessee State University College of Medicine, Johnson City, TN, USA
| | - William Curtis
- Department of Biomedical Sciences, East Tennessee State University College of Medicine, Johnson City, TN, USA
| |
Collapse
|