1
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Skalka GL, Tsakovska M, Murphy DJ. Kinase signalling adaptation supports dysfunctional mitochondria in disease. Front Mol Biosci 2024; 11:1354682. [PMID: 38434478 PMCID: PMC10906720 DOI: 10.3389/fmolb.2024.1354682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
Mitochondria form a critical control nexus which are essential for maintaining correct tissue homeostasis. An increasing number of studies have identified dysregulation of mitochondria as a driver in cancer. However, which pathways support and promote this adapted mitochondrial function? A key hallmark of cancer is perturbation of kinase signalling pathways. These pathways include mitogen activated protein kinases (MAPK), lipid secondary messenger networks, cyclic-AMP-activated (cAMP)/AMP-activated kinases (AMPK), and Ca2+/calmodulin-dependent protein kinase (CaMK) networks. These signalling pathways have multiple substrates which support initiation and persistence of cancer. Many of these are involved in the regulation of mitochondrial morphology, mitochondrial apoptosis, mitochondrial calcium homeostasis, mitochondrial associated membranes (MAMs), and retrograde ROS signalling. This review will aim to both explore how kinase signalling integrates with these critical mitochondrial pathways and highlight how these systems can be usurped to support the development of disease. In addition, we will identify areas which require further investigation to fully understand the complexities of these regulatory interactions. Overall, this review will emphasize how studying the interaction between kinase signalling and mitochondria improves our understanding of mitochondrial homeostasis and can yield novel therapeutic targets to treat disease.
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Affiliation(s)
- George L. Skalka
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Mina Tsakovska
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Daniel J. Murphy
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
- CRUK Scotland Institute, Glasgow, United Kingdom
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2
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Yuan Y, Wang F, Liu X, Shuai B, Fan H. The Role of AMPK Signaling in Ulcerative Colitis. Drug Des Devel Ther 2023; 17:3855-3875. [PMID: 38170149 PMCID: PMC10759424 DOI: 10.2147/dddt.s442154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024] Open
Abstract
Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease characterized by inflammation and ulcer formation of the intestinal mucosa. Due to its high recurrence rate, prolonged course, limited curative options, and significant impact on patients' quality of life, along with a notable potential for malignant transformation, UC is designated as a refractory global health challenge by the World Health Organization (WHO). The elucidation of the pathogenesis and therapeutic strategies for UC requires further in-depth investigation. AMP-activated protein kinase (AMPK) serves as a central regulator of cellular energy metabolic homeostasis. Emerging evidence indicates that interventions involving traditional Chinese medicine (TCM) components, as well as other pharmacological measures, exert beneficial effects on the intestinal mucosal inflammation and epithelial barrier dysfunction in UC by modulating AMPK signaling, thereby influencing biological processes such as cellular autophagy, apoptosis, inflammatory responses, macrophage polarization, and NLRP3 inflammasome-mediated pyroptosis. The role of AMPK in UC is of significant importance. This manuscript provides a comprehensive overview of the mechanisms through which AMPK is involved in UC, as well as a compilation of pharmacological agents capable of activating the AMPK signaling pathway within the context of UC. The primary objective is to facilitate a deeper comprehension of the pivotal role of AMPK in UC among researchers and clinical practitioners, thereby advancing the identification of novel therapeutic targets for interventions in UC.
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Affiliation(s)
- Yuyi Yuan
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| | - Fang Wang
- Department of Rehabilitation Medicine, Jingshan Union Hospital, Union Hospital, Huazhong University of Science and Technology, Jingshan, Hubei, 431800, People’s Republic of China
| | - Xingxing Liu
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| | - Bo Shuai
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
| | - Heng Fan
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China
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3
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Hawley SA, Russell FM, Ross FA, Hardie DG. BAY-3827 and SBI-0206965: Potent AMPK Inhibitors That Paradoxically Increase Thr172 Phosphorylation. Int J Mol Sci 2023; 25:453. [PMID: 38203624 PMCID: PMC10778976 DOI: 10.3390/ijms25010453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/07/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
AMP-activated protein kinase (AMPK) is the central component of a signalling pathway that senses energy stress and triggers a metabolic switch away from anabolic processes and towards catabolic processes. There has been a prolonged focus in the pharmaceutical industry on the development of AMPK-activating drugs for the treatment of metabolic disorders such as Type 2 diabetes and non-alcoholic fatty liver disease. However, recent findings suggest that AMPK inhibitors might be efficacious for treating certain cancers, especially lung adenocarcinomas, in which the PRKAA1 gene (encoding the α1 catalytic subunit isoform of AMPK) is often amplified. Here, we study two potent AMPK inhibitors, BAY-3827 and SBI-0206965. Despite not being closely related structurally, the treatment of cells with either drug unexpectedly caused increases in AMPK phosphorylation at the activating site, Thr172, even though the phosphorylation of several downstream targets in different subcellular compartments was completely inhibited. Surprisingly, the two inhibitors appear to promote Thr172 phosphorylation by different mechanisms: BAY-3827 primarily protects against Thr172 dephosphorylation, while SBI-0206965 also promotes phosphorylation by LKB1 at low concentrations, while increasing cellular AMP:ATP ratios at higher concentrations. Due to its greater potency and fewer off-target effects, BAY-3827 is now the inhibitor of choice for cell studies, although its low bioavailability may limit its use in vivo.
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Affiliation(s)
| | | | | | - D. Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK; (S.A.H.); (F.A.R.)
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4
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Li X, Bi X. Integrated Control of Fatty Acid Metabolism in Heart Failure. Metabolites 2023; 13:615. [PMID: 37233656 PMCID: PMC10220550 DOI: 10.3390/metabo13050615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 05/27/2023] Open
Abstract
Disrupted fatty acid metabolism is one of the most important metabolic features in heart failure. The heart obtains energy from fatty acids via oxidation. However, heart failure results in markedly decreased fatty acid oxidation and is accompanied by the accumulation of excess lipid moieties that lead to cardiac lipotoxicity. Herein, we summarized and discussed the current understanding of the integrated regulation of fatty acid metabolism (including fatty acid uptake, lipogenesis, lipolysis, and fatty acid oxidation) in the pathogenesis of heart failure. The functions of many enzymes and regulatory factors in fatty acid homeostasis were characterized. We reviewed their contributions to the development of heart failure and highlighted potential targets that may serve as promising new therapeutic strategies.
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Affiliation(s)
| | - Xukun Bi
- Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China;
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5
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Steinberg GR, Hardie DG. New insights into activation and function of the AMPK. Nat Rev Mol Cell Biol 2023; 24:255-272. [PMID: 36316383 DOI: 10.1038/s41580-022-00547-x] [Citation(s) in RCA: 185] [Impact Index Per Article: 185.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2022] [Indexed: 11/06/2022]
Abstract
The classical role of AMP-activated protein kinase (AMPK) is as a cellular energy sensor activated by falling energy status, signalled by increases in AMP to ATP and ADP to ATP ratios. Once activated, AMPK acts to restore energy homeostasis by promoting ATP-producing catabolic pathways while inhibiting energy-consuming processes. In this Review, we provide an update on this canonical (AMP/ADP-dependent) activation mechanism, but focus mainly on recently described non-canonical pathways, including those by which AMPK senses the availability of glucose, glycogen or fatty acids and by which it senses damage to lysosomes and nuclear DNA. We also discuss new findings on the regulation of carbohydrate and lipid metabolism, mitochondrial and lysosomal homeostasis, and DNA repair. Finally, we discuss the role of AMPK in cancer, obesity, diabetes, nonalcoholic steatohepatitis (NASH) and other disorders where therapeutic targeting may exert beneficial effects.
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Affiliation(s)
- Gregory R Steinberg
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada.
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
| | - D Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dundee, UK.
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6
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Colangeli L, Escobar Marcillo DI, Simonelli V, Iorio E, Rinaldi T, Sbraccia P, Fortini P, Guglielmi V. The Crosstalk between Gut Microbiota and White Adipose Tissue Mitochondria in Obesity. Nutrients 2023; 15:nu15071723. [PMID: 37049562 PMCID: PMC10097238 DOI: 10.3390/nu15071723] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/19/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023] Open
Abstract
Adipose tissue (AT) dysregulation is a key process in the pathophysiology of obesity and its cardiometabolic complications, but even if a growing body of evidence has been collected over recent decades, the underlying molecular basis of adiposopathy remains to be fully understood. In this context, mitochondria, the intracellular organelles that orchestrate energy production and undergo highly dynamic adaptive changes in response to changing environments, have emerged as crucial regulators of both white (WAT) and brown adipose tissue (BAT) metabolism and function. Given that the gut microbiota and its metabolites are able to regulate host metabolism, adipogenesis, WAT inflammation, and thermogenesis, we hypothesize that their frequently observed dysregulation in obesity could affect AT metabolism by exerting direct and indirect effects on AT mitochondria. By collecting and revising the current evidence on the connections between gut microbiota and AT mitochondria in obesity, we gained insights into the molecular biology of their hitherto largely unexplored crosstalk, tracing how gut microbiota may regulate AT mitochondrial function.
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7
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Eyme KM, Sammarco A, Jha R, Mnatsakanyan H, Pechdimaljian C, Carvalho L, Neustadt R, Moses C, Alnasser A, Tardiff DF, Su B, Williams KJ, Bensinger SJ, Chung CY, Badr CE. Targeting de novo lipid synthesis induces lipotoxicity and impairs DNA damage repair in glioblastoma mouse models. Sci Transl Med 2023; 15:eabq6288. [PMID: 36652537 PMCID: PMC9942236 DOI: 10.1126/scitranslmed.abq6288] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Deregulated de novo lipid synthesis (DNLS) is a potential druggable vulnerability in glioblastoma (GBM), a highly lethal and incurable cancer. Yet the molecular mechanisms that determine susceptibility to DNLS-targeted therapies remain unknown, and the lack of brain-penetrant inhibitors of DNLS has prevented their clinical evaluation as GBM therapeutics. Here, we report that YTX-7739, a clinical-stage inhibitor of stearoyl CoA desaturase (SCD), triggers lipotoxicity in patient-derived GBM stem-like cells (GSCs) and inhibits fatty acid desaturation in GSCs orthotopically implanted in mice. When administered as a single agent, or in combination with temozolomide (TMZ), YTX-7739 showed therapeutic efficacy in orthotopic GSC mouse models owing to its lipotoxicity and ability to impair DNA damage repair. Leveraging genetic, pharmacological, and physiological manipulation of key signaling nodes in gliomagenesis complemented with shotgun lipidomics, we show that aberrant MEK/ERK signaling and its repression of the energy sensor AMP-activated protein kinase (AMPK) primarily drive therapeutic vulnerability to SCD and other DNLS inhibitors. Conversely, AMPK activation mitigates lipotoxicity and renders GSCs resistant to the loss of DNLS, both in culture and in vivo, by decreasing the saturation state of phospholipids and diverting toxic lipids into lipid droplets. Together, our findings reveal mechanisms of metabolic plasticity in GSCs and provide a framework for the rational integration of DNLS-targeted GBM therapies.
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Affiliation(s)
- Katharina M. Eyme
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129,Department of Neurology, Heidelberg University Hospital, Heidelberg, Germany
| | - Alessandro Sammarco
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129,Department of Comparative Biomedicine and Food Science, University of Padua, Padua, Italy,Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, USA 90095
| | - Roshani Jha
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129
| | - Hayk Mnatsakanyan
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129
| | - Caline Pechdimaljian
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129
| | - Litia Carvalho
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129,Neuroscience Program, Harvard Medical School, Boston, MA, USA 02115
| | - Rudolph Neustadt
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129
| | - Charlotte Moses
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129
| | - Ahmad Alnasser
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129
| | | | - Baolong Su
- Department of Biological Chemistry, University of California, Los Angeles, CA, USA 90095,UCLA Lipidomics Laboratory, University of California, Los Angeles, CA, USA 90095
| | - Kevin J. Williams
- Department of Biological Chemistry, University of California, Los Angeles, CA, USA 90095,UCLA Lipidomics Laboratory, University of California, Los Angeles, CA, USA 90095
| | - Steven J. Bensinger
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, USA 90095,UCLA Lipidomics Laboratory, University of California, Los Angeles, CA, USA 90095
| | | | - Christian E. Badr
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 02129,Neuroscience Program, Harvard Medical School, Boston, MA, USA 02115,Correspondence:
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8
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Hardie DG. AMP-activated protein kinase - a journey from 1 to 100 downstream targets. Biochem J 2022; 479:2327-2343. [PMID: 36383046 PMCID: PMC9704532 DOI: 10.1042/bcj20220255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 10/26/2022] [Accepted: 10/26/2022] [Indexed: 11/17/2022]
Abstract
A casual decision made one evening in 1976, in a bar near the Biochemistry Department at the University of Dundee, led me to start my personal research journey by following up a paper that suggested that acetyl-CoA carboxylase (ACC) (believed to be a key regulatory enzyme of fatty acid synthesis) was inactivated by phosphorylation by what appeared to be a novel, cyclic AMP-independent protein kinase. This led me to define and name the AMP-activated protein kinase (AMPK) signalling pathway, on which I am still working 46 years later. ACC was the first known downstream target for AMPK, but at least 100 others have now been identified. This article contains some personal reminiscences of that research journey, focussing on: (i) the early days when we were defining the kinase and developing the key tools required to study it; (ii) the late 1990s and early 2000s, an exciting time when we and others were identifying the upstream kinases; (iii) recent times when we have been studying the complex role of AMPK in cancer. The article is published in conjunction with the Sir Philip Randle Lecture of the Biochemical Society, which I gave in September 2022 at the European Workshop on AMPK and AMPK-related kinases in Clydebank, Scotland. During the early years of my research career, Sir Philip acted as a role model, due to his pioneering work on insulin signalling and the regulation of pyruvate dehydrogenase.
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Affiliation(s)
- D. Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, Scotland, U.K
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9
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Hsu CC, Peng D, Cai Z, Lin HK. AMPK signaling and its targeting in cancer progression and treatment. Semin Cancer Biol 2022; 85:52-68. [PMID: 33862221 PMCID: PMC9768867 DOI: 10.1016/j.semcancer.2021.04.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/06/2021] [Accepted: 04/07/2021] [Indexed: 12/24/2022]
Abstract
The intrinsic mechanisms sensing the imbalance of energy in cells are pivotal for cell survival under various environmental insults. AMP-activated protein kinase (AMPK) serves as a central guardian maintaining energy homeostasis by orchestrating diverse cellular processes, such as lipogenesis, glycolysis, TCA cycle, cell cycle progression and mitochondrial dynamics. Given that AMPK plays an essential role in the maintenance of energy balance and metabolism, managing AMPK activation is considered as a promising strategy for the treatment of metabolic disorders such as type 2 diabetes and obesity. Since AMPK has been attributed to aberrant activation of metabolic pathways, mitochondrial dynamics and functions, and epigenetic regulation, which are hallmarks of cancer, targeting AMPK may open up a new avenue for cancer therapies. Although AMPK is previously thought to be involved in tumor suppression, several recent studies have unraveled its tumor promoting activity. The double-edged sword characteristics for AMPK as a tumor suppressor or an oncogene are determined by distinct cellular contexts. In this review, we will summarize recent progress in dissecting the upstream regulators and downstream effectors for AMPK, discuss the distinct roles of AMPK in cancer regulation and finally offer potential strategies with AMPK targeting in cancer therapy.
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Affiliation(s)
- Che-Chia Hsu
- Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston-Salem, NC, 27101, USA
| | - Danni Peng
- Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston-Salem, NC, 27101, USA
| | - Zhen Cai
- Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston-Salem, NC, 27101, USA.
| | - Hui-Kuan Lin
- Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston-Salem, NC, 27101, USA.
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10
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López M. Hypothalamic AMPK as a possible target for energy balance-related diseases. Trends Pharmacol Sci 2022; 43:546-556. [DOI: 10.1016/j.tips.2022.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 04/14/2022] [Accepted: 04/15/2022] [Indexed: 10/18/2022]
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11
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Liu Y, Wang TV, Cui Y, Gao S, Rao Y. Biochemical purification uncovers mammalian sterile 3 (MST3) as a new protein kinase for multifunctional protein kinases AMPK and SIK3. J Biol Chem 2022; 298:101929. [PMID: 35413286 PMCID: PMC9112001 DOI: 10.1016/j.jbc.2022.101929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/30/2022] [Accepted: 04/01/2022] [Indexed: 11/30/2022] Open
Abstract
The AMP-activated protein kinase (AMPK) and AMPK-related kinase salt-inducible kinase 3 (SIK3) regulate many important biological processes ranging from metabolism to sleep. Liver kinase B1 is known to phosphorylate and activate both AMPK and SIK3, but the existence of other upstream kinases was unclear. In this study, we detected liver kinase B1-independent AMPK-related kinase phosphorylation activities in human embryonic kidney cells as well as in mouse brains. Biochemical purification of this phosphorylation activity uncovered mammalian sterile 20-like kinase 3 (MST3). We demonstrate that MST3 from human embryonic kidney cells could phosphorylate AMPK and SIK3 in vivo. In addition, recombinant MST3 expressed in and purified from Escherichia coli could directly phosphorylate AMPK and SIK3 in vitro. Moreover, four other members of the MST kinase family could also phosphorylate AMPK or SIK3. Our results have revealed new kinases able to phosphorylate and activate AMPK and SIK3.
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Affiliation(s)
- Yuxiang Liu
- Laboratory of Neurochemical Biology, Department of Chemical Biology, College of Chemistry and Chemical Engineering, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, School of Pharmaceutical Sciences, Health Sciences Center, Peking University, Beijing, China; Chinese Institute for Brain Research, Beijing, China; School of Basic Medical Sciences, Capital Medical University, Beijing, China; Changping Laboratory, Beijing, China
| | - Tao V Wang
- Laboratory of Neurochemical Biology, Department of Chemical Biology, College of Chemistry and Chemical Engineering, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, School of Pharmaceutical Sciences, Health Sciences Center, Peking University, Beijing, China; Chinese Institute for Brain Research, Beijing, China; School of Basic Medical Sciences, Capital Medical University, Beijing, China; Changping Laboratory, Beijing, China
| | - Yunfeng Cui
- Laboratory of Neurochemical Biology, Department of Chemical Biology, College of Chemistry and Chemical Engineering, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, School of Pharmaceutical Sciences, Health Sciences Center, Peking University, Beijing, China; Chinese Institute for Brain Research, Beijing, China; School of Basic Medical Sciences, Capital Medical University, Beijing, China; Changping Laboratory, Beijing, China
| | - Shengxian Gao
- Laboratory of Neurochemical Biology, Department of Chemical Biology, College of Chemistry and Chemical Engineering, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, School of Pharmaceutical Sciences, Health Sciences Center, Peking University, Beijing, China; Chinese Institute for Brain Research, Beijing, China; School of Basic Medical Sciences, Capital Medical University, Beijing, China; Changping Laboratory, Beijing, China
| | - Yi Rao
- Laboratory of Neurochemical Biology, Department of Chemical Biology, College of Chemistry and Chemical Engineering, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, School of Pharmaceutical Sciences, Health Sciences Center, Peking University, Beijing, China; Chinese Institute for Brain Research, Beijing, China; School of Basic Medical Sciences, Capital Medical University, Beijing, China; Changping Laboratory, Beijing, China.
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12
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King KE, Losier TT, Russell RC. Regulation of Autophagy Enzymes by Nutrient Signaling. Trends Biochem Sci 2021; 46:687-700. [PMID: 33593593 DOI: 10.1016/j.tibs.2021.01.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 01/12/2021] [Accepted: 01/21/2021] [Indexed: 02/07/2023]
Abstract
Autophagy is the primary catabolic program of the cell that promotes survival in response to metabolic stress. It is tightly regulated by a suite of kinases responsive to nutrient status, including mammalian target of rapamycin complex 1 (mTORC1), AMP-activated protein kinase (AMPK), protein kinase C-α (PKCα), MAPK-activated protein kinases 2/3 (MAPKAPK2/3), Rho kinase 1 (ROCK1), c-Jun N-terminal kinase 1 (JNK), and Casein kinase 2 (CSNK2). Here, we highlight recently uncovered mechanisms linking amino acid, glucose, and oxygen levels to autophagy regulation through mTORC1 and AMPK. In addition, we describe new pathways governing the autophagic machinery, including the Unc-51-like (ULK1), vacuolar protein sorting 34 (VPS34), and autophagy related 16 like 1 (ATG16L1) enzyme complexes. Novel downstream targets of ULK1 protein kinase are also discussed, such as the ATG16L1 subunit of the microtubule-associated protein 1 light chain 3 (LC3)-lipidating enzyme and the ATG14 subunit of the VPS34 complex. Collectively, we describe the complexities of the autophagy pathway and its role in maintaining cellular nutrient homeostasis during times of starvation.
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Affiliation(s)
- Karyn E King
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ONT, Canada
| | - Truc T Losier
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ONT, Canada
| | - Ryan C Russell
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ONT, Canada; Center for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, ONT, Canada; Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ONT, Canada.
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13
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Yuan J, Dong X, Yap J, Hu J. The MAPK and AMPK signalings: interplay and implication in targeted cancer therapy. J Hematol Oncol 2020; 13:113. [PMID: 32807225 PMCID: PMC7433213 DOI: 10.1186/s13045-020-00949-4] [Citation(s) in RCA: 248] [Impact Index Per Article: 62.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/04/2020] [Indexed: 02/06/2023] Open
Abstract
Cancer is characterized as a complex disease caused by coordinated alterations of multiple signaling pathways. The Ras/RAF/MEK/ERK (MAPK) signaling is one of the best-defined pathways in cancer biology, and its hyperactivation is responsible for over 40% human cancer cases. To drive carcinogenesis, this signaling promotes cellular overgrowth by turning on proliferative genes, and simultaneously enables cells to overcome metabolic stress by inhibiting AMPK signaling, a key singular node of cellular metabolism. Recent studies have shown that AMPK signaling can also reversibly regulate hyperactive MAPK signaling in cancer cells by phosphorylating its key components, RAF/KSR family kinases, which affects not only carcinogenesis but also the outcomes of targeted cancer therapies against the MAPK signaling. In this review, we will summarize the current proceedings of how MAPK-AMPK signalings interplay with each other in cancer biology, as well as its implications in clinic cancer treatment with MAPK inhibition and AMPK modulators, and discuss the exploitation of combinatory therapies targeting both MAPK and AMPK as a novel therapeutic intervention.
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Affiliation(s)
- Jimin Yuan
- Department of Urology, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, 518020, Guangdong, China.
- Geriatric Department, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, 518020, Guangdong, China.
| | - Xiaoduo Dong
- Shenzhen People's Hospital, 1017 Dongmen North Road, Shenzhen, 518020, China
| | - Jiajun Yap
- Cancer and Stem Cell Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Jiancheng Hu
- Cancer and Stem Cell Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore.
- Division of Cellular and Molecular Research, National Cancer Centre Singapore, 11 Hospital Drive, Singapore, 169610, Singapore.
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14
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González A, Hall MN, Lin SC, Hardie DG. AMPK and TOR: The Yin and Yang of Cellular Nutrient Sensing and Growth Control. Cell Metab 2020; 31:472-492. [PMID: 32130880 DOI: 10.1016/j.cmet.2020.01.015] [Citation(s) in RCA: 404] [Impact Index Per Article: 101.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The AMPK (AMP-activated protein kinase) and TOR (target-of-rapamycin) pathways are interlinked, opposing signaling pathways involved in sensing availability of nutrients and energy and regulation of cell growth. AMPK (Yin, or the "dark side") is switched on by lack of energy or nutrients and inhibits cell growth, while TOR (Yang, or the "bright side") is switched on by nutrient availability and promotes cell growth. Genes encoding the AMPK and TOR complexes are found in almost all eukaryotes, suggesting that these pathways arose very early during eukaryotic evolution. During the development of multicellularity, an additional tier of cell-extrinsic growth control arose that is mediated by growth factors, but these often act by modulating nutrient uptake so that AMPK and TOR remain the underlying regulators of cellular growth control. In this review, we discuss the evolution, structure, and regulation of the AMPK and TOR pathways and the complex mechanisms by which they interact.
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Affiliation(s)
- Asier González
- Biozentrum, University of Basel, CH4056 Basel, Switzerland
| | - Michael N Hall
- Biozentrum, University of Basel, CH4056 Basel, Switzerland
| | - Sheng-Cai Lin
- School of Life Sciences, Xiamen University, Xiamen, 361102 Fujian, China
| | - D Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK.
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15
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Abstract
Coronary heart disease (CHD) is the most common and serious illness in the world and has been researched for many years. However, there are still no real effective ways to prevent and save patients with this disease. When patients present with myocardial infarction, the most important step is to recover ischemic prefusion, which usually is accomplished by coronary artery bypass surgery, coronary artery intervention (PCI), or coronary artery bypass grafting (CABG). These are invasive procedures, and patients with extensive lesions cannot tolerate surgery. It is, therefore, extremely urgent to search for a noninvasive way to save ischemic myocardium. After suffering from ischemia, cardiac or skeletal muscle can partly recover blood flow through angiogenesis (de novo capillary) induced by hypoxia, arteriogenesis, or collateral growth (opening and remodeling of arterioles) triggered by dramatical increase of fluid shear stress (FSS). Evidence has shown that both of them are regulated by various crossed pathways, such as hypoxia-related pathways, cellular metabolism remodeling, inflammatory cells invasion and infiltration, or hemodynamical changes within the vascular wall, but still they do not find effective target for regulating revascularization at present. 5′-Adenosine monophosphate-activated protein kinase (AMPK), as a kinase, is not only an energy modulator but also a sensor of cellular oxygen-reduction substances, and many researches have suggested that AMPK plays an essential role in revascularization but the mechanism is not completely understood. Usually, AMPK can be activated by ADP or AMP, upstream kinases or other cytokines, and pharmacological agents, and then it phosphorylates key molecules that are involved in energy metabolism, autophagy, anti-inflammation, oxidative stress, and aging process to keep cellular homeostasis and finally keeps cell normal activity and function. This review makes a summary on the subunits, activation and downstream targets of AMPK, the mechanism of revascularization, the effects of AMPK in endothelial cells, angiogenesis, and arteriogenesis along with some prospects.
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16
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Heinonen S, Jokinen R, Rissanen A, Pietiläinen KH. White adipose tissue mitochondrial metabolism in health and in obesity. Obes Rev 2020; 21:e12958. [PMID: 31777187 DOI: 10.1111/obr.12958] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 08/27/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022]
Abstract
White adipose tissue is one of the largest organs of the body. It plays a key role in whole-body energy status and metabolism; it not only stores excess energy but also secretes various hormones and metabolites to regulate body energy balance. Healthy adipose tissue capable of expanding is needed for metabolic well-being and to prevent accumulation of triglycerides to other organs. Mitochondria govern several important functions in the adipose tissue. We review the derangements of mitochondrial function in white adipose tissue in the obese state. Downregulation of mitochondrial function or biogenesis in the white adipose tissue is a central driver for obesity-associated metabolic diseases. Mitochondrial functions compromised in obesity include oxidative functions and renewal and enlargement of the adipose tissue through recruitment and differentiation of adipocyte progenitor cells. These changes adversely affect whole-body metabolic health. Dysfunction of the white adipose tissue mitochondria in obesity has long-term consequences for the metabolism of adipose tissue and the whole body. Understanding the pathways behind mitochondrial dysfunction may help reveal targets for pharmacological or nutritional interventions that enhance mitochondrial biogenesis or function in adipose tissue.
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Affiliation(s)
- Sini Heinonen
- Obesity Research Unit, Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Riikka Jokinen
- Obesity Research Unit, Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Aila Rissanen
- Obesity Research Unit, Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland.,Department of Psychiatry, Helsinki University Hospital, Helsinki, Finland
| | - Kirsi H Pietiläinen
- Obesity Research Unit, Research Program for Clinical and Molecular Metabolism, Faculty of Medicine, University of Helsinki, Helsinki, Finland.,Endocrinology, Abdominal Center, Helsinki University Hospital, Helsinki, Finland
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17
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Hawley SA, Ross FA, Russell FM, Atrih A, Lamont DJ, Hardie DG. Mechanism of Activation of AMPK by Cordycepin. Cell Chem Biol 2020; 27:214-222.e4. [PMID: 31991096 PMCID: PMC7031697 DOI: 10.1016/j.chembiol.2020.01.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 11/27/2019] [Accepted: 01/06/2020] [Indexed: 12/22/2022]
Abstract
Cordycepin (3′-deoxyadenosine) is a major bioactive agent in Cordyceps militaris, a fungus used in traditional Chinese medicine. It has been proposed to have many beneficial metabolic effects by activating AMP-activated protein kinase (AMPK), but the mechanism of activation remained uncertain. We report that cordycepin enters cells via adenosine transporters and is converted by cellular metabolism into mono-, di-, and triphosphates, which at high cordycepin concentrations can almost replace cellular adenine nucleotides. AMPK activation by cordycepin in intact cells correlates with the content of cordycepin monophosphate and not other cordycepin or adenine nucleotides. Genetic knockout of AMPK sensitizes cells to the cytotoxic effects of cordycepin. In cell-free assays, cordycepin monophosphate mimics all three effects of AMP on AMPK, while activation in cells is blocked by a γ-subunit mutation that prevents activation by AMP. Thus, cordycepin is a pro-drug that activates AMPK by being converted by cellular metabolism into the AMP analog cordycepin monophosphate. Cordycepin (100 μM) activates AMPK in human cells; higher concentrations are toxic Cordycepin is taken up into cells and converted into mono-, di-, and triphosphates AMPK activation correlates with the cellular content of cordycepin monophosphate Cordycepin monophosphate mimics all three effects of AMP on AMPK in cell-free assays
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Affiliation(s)
- Simon A Hawley
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Fiona A Ross
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Fiona M Russell
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Abdelmadjid Atrih
- Fingerprints Proteomics Facility, School of Life Sciences, University of Dundee, Dundee, UK
| | - Douglas J Lamont
- Fingerprints Proteomics Facility, School of Life Sciences, University of Dundee, Dundee, UK
| | - D Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
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18
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Vara-Ciruelos D, Russell FM, Hardie DG. The strange case of AMPK and cancer: Dr Jekyll or Mr Hyde? †. Open Biol 2019; 9:190099. [PMID: 31288625 PMCID: PMC6685927 DOI: 10.1098/rsob.190099] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 06/11/2019] [Indexed: 02/06/2023] Open
Abstract
The AMP-activated protein kinase (AMPK) acts as a cellular energy sensor. Once switched on by increases in cellular AMP : ATP ratios, it acts to restore energy homeostasis by switching on catabolic pathways while switching off cell growth and proliferation. The canonical AMP-dependent mechanism of activation requires the upstream kinase LKB1, which was identified genetically to be a tumour suppressor. AMPK can also be switched on by increases in intracellular Ca2+, by glucose starvation and by DNA damage via non-canonical, AMP-independent pathways. Genetic studies of the role of AMPK in mouse cancer suggest that, before disease arises, AMPK acts as a tumour suppressor that protects against cancer, with this protection being further enhanced by AMPK activators such as the biguanide phenformin. However, once cancer has occurred, AMPK switches to being a tumour promoter instead, enhancing cancer cell survival by protecting against metabolic, oxidative and genotoxic stresses. Studies of genetic changes in human cancer also suggest diverging roles for genes encoding subunit isoforms, with some being frequently amplified, while others are mutated.
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Affiliation(s)
| | | | - D. Grahame Hardie
- Division of Cell Signalling and Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
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19
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Abstract
AMP-activated protein kinase (AMPK) is the main cellular energy sensor. Activated following a depletion of cellular energy stores, AMPK will restore the energy homoeostasis by increasing energy production and limiting energy waste. At a central level, the AMPK pathway will integrate peripheral signals (mostly hormones and metabolites) through neuronal networks. Hypothalamic AMPK is directly implicated in feeding behaviour, brown adipose tissue (BAT) thermogenesis and browning of white adipose tissue (WAT). It also participates in other metabolic functions: glucose and muscle metabolisms, as well as hepatic function. Numerous anti-obesity and/or antidiabetic agents, such as nicotine, metformin and liraglutide, are known to induce their effects through a modulation of AMPK pathway, either at central or at peripheral levels. Moreover, the weight-gaining side effects of antipsychotic drugs, such as olanzapine, are also mediated by hypothalamic AMPK. Therefore, considering hypothalamic AMPK as a therapeutic target in metabolic diseases appears as an interesting strategy due to its implication in feeding and energy expenditure, the two sides of the energy balance equation.
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Affiliation(s)
- Miguel López
- NeurObesity Group, Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain
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20
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Esquejo RM, Salatto CT, Delmore J, Albuquerque B, Reyes A, Shi Y, Moccia R, Cokorinos E, Peloquin M, Monetti M, Barricklow J, Bollinger E, Smith BK, Day EA, Nguyen C, Geoghegan KF, Kreeger JM, Opsahl A, Ward J, Kalgutkar AS, Tess D, Butler L, Shirai N, Osborne TF, Steinberg GR, Birnbaum MJ, Cameron KO, Miller RA. Activation of Liver AMPK with PF-06409577 Corrects NAFLD and Lowers Cholesterol in Rodent and Primate Preclinical Models. EBioMedicine 2018; 31:122-132. [PMID: 29673898 PMCID: PMC6014578 DOI: 10.1016/j.ebiom.2018.04.009] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 03/26/2018] [Accepted: 04/06/2018] [Indexed: 12/28/2022] Open
Abstract
Dysregulation of hepatic lipid and cholesterol metabolism is a significant contributor to cardiometabolic health, resulting in excessive liver lipid accumulation and ultimately non-alcoholic steatohepatitis (NASH). Therapeutic activators of the AMP-Activated Protein Kinase (AMPK) have been proposed as a treatment for metabolic diseases; we show that the AMPK β1-biased activator PF-06409577 is capable of lowering hepatic and systemic lipid and cholesterol levels in both rodent and monkey preclinical models. PF-06409577 is able to inhibit de novo lipid and cholesterol synthesis pathways, and causes a reduction in hepatic lipids and mRNA expression of markers of hepatic fibrosis. These effects require AMPK activity in the hepatocytes. Treatment of hyperlipidemic rats or cynomolgus monkeys with PF-06409577 for 6 weeks resulted in a reduction in circulating cholesterol. Together these data suggest that activation of AMPK β1 complexes with PF-06409577 is capable of impacting multiple facets of liver disease and represents a promising strategy for the treatment of NAFLD and NASH in humans. PF-06409577 is a potent activator of AMPK β1 containing complexes. PF-06409577 improves liver function and systemic dyslipidemia in rodents through hepatic AMPK activation. PF-06409577-mediated reductions in circulating cholesterol was observed in monkeys and diabetic rats.
NAFLD and NASH remain poorly treated and are diseases which are growing rapidly in societal cost. Therapeutic mechanisms that impact multiple aspects of the dysregulated metabolic regulation of NAFLD and NASH are needed. Pharmacological AMPK activation has long held promise as a treatment for NAFLD because of its impact on hepatic lipid and cholesterol synthesis, as well as its proposed anti-inflammatory and anti-lipolytic actions. Recent development of clinically viable small molecule AMPK activators, including PF-06409577, has enabled their more thorough characterization in preclinical disease models.
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Affiliation(s)
- Ryan M Esquejo
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | | | - Jake Delmore
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | | | - Allan Reyes
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | - Yuji Shi
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | - Rob Moccia
- Computational Sciences, Pfizer Inc, Cambridge, MA, USA
| | - Emily Cokorinos
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | | | - Mara Monetti
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | - Jason Barricklow
- Pharmacokinetics, Dynamics, and Metabolism, Pfizer Inc, Groton, CT, USA
| | - Eliza Bollinger
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | - Brennan K Smith
- Division of Endocrinology and Metabolism, Department of Medicine and Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main St. W., Hamilton, ON L8N 3Z5, Canada
| | - Emily A Day
- Division of Endocrinology and Metabolism, Department of Medicine and Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main St. W., Hamilton, ON L8N 3Z5, Canada
| | - Chuong Nguyen
- Primary Pharmacology Group, Pfizer Inc, Groton, CT, USA
| | | | - John M Kreeger
- Drug Safety Research and Development, Pfizer Inc, Groton, CT, USA
| | - Alan Opsahl
- Drug Safety Research and Development, Pfizer Inc, Groton, CT, USA
| | - Jessica Ward
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA
| | - Amit S Kalgutkar
- Sanford Burnham Prebys Medical Discovery Institute, 6400 Sanger Road, Orlando, FL 32827, USA
| | - David Tess
- Sanford Burnham Prebys Medical Discovery Institute, 6400 Sanger Road, Orlando, FL 32827, USA
| | - Lynne Butler
- Drug Safety Research and Development, Pfizer Inc, Groton, CT, USA
| | - Norimitsu Shirai
- Drug Safety Research and Development, Pfizer Inc, Groton, CT, USA
| | - Timothy F Osborne
- Sanford Burnham Prebys Medical Discovery Institute, 6400 Sanger Road, Orlando, FL 32827, USA
| | - Gregory R Steinberg
- Division of Endocrinology and Metabolism, Department of Medicine and Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main St. W., Hamilton, ON L8N 3Z5, Canada
| | | | | | - Russell A Miller
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, USA.
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21
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Suppression of gain-of-function mutant p53 with metabolic inhibitors reduces tumor growth in vivo. Oncotarget 2018; 7:77664-77682. [PMID: 27765910 PMCID: PMC5363612 DOI: 10.18632/oncotarget.12758] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 09/26/2016] [Indexed: 12/25/2022] Open
Abstract
Mutation of p53 occasionally results in a gain of function, which promotes tumor growth. We asked whether destabilizing the gain-of-function protein would kill tumor cells. Downregulation of the gene reduced cell proliferation in p53-mutant cells, but not in p53-null cells, indicating that the former depended on the mutant protein for survival. Moreover, phenformin and 2-deoxyglucose suppressed cell growth and simultaneously destabilized mutant p53. The AMPK pathway, MAPK pathway, chaperone proteins and ubiquitination all contributed to this process. Interestingly, phenformin and 2-deoxyglucose also reduced tumor growth in syngeneic mice harboring the p53 mutation. Thus, destabilizing mutant p53 protein in order to kill cells exhibiting "oncogene addiction" could be a promising strategy for combatting p53 mutant tumors.
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22
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Abstract
Mammalian AMPK is known to be activated by falling cellular energy status, signaled by rising AMP/ATP and ADP/ATP ratios. We review recent information about how this occurs but also discuss new studies suggesting that AMPK is able to sense glucose availability independently of changes in adenine nucleotides. The glycolytic intermediate fructose-1,6-bisphosphate (FBP) is sensed by aldolase, which binds to the v-ATPase on the lysosomal surface. In the absence of FBP, interactions between aldolase and the v-ATPase are altered, allowing formation of an AXIN-based AMPK-activation complex containing the v-ATPase, Ragulator, AXIN, LKB1, and AMPK, causing increased Thr172 phosphorylation and AMPK activation. This nutrient-sensing mechanism activates AMPK but also primes it for further activation if cellular energy status subsequently falls. Glucose sensing at the lysosome, in which AMPK and other components of the activation complex act antagonistically with another key nutrient sensor, mTORC1, may have been one of the ancestral roles of AMPK.
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Affiliation(s)
- Sheng-Cai Lin
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiang'an Campus, Xiamen, Fujian 361102, China.
| | - D Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
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23
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Cid‐Díaz T, Santos‐Zas I, González‐Sánchez J, Gurriarán‐Rodríguez U, Mosteiro CS, Casabiell X, García‐Caballero T, Mouly V, Pazos Y, Camiña JP. Obestatin controls the ubiquitin-proteasome and autophagy-lysosome systems in glucocorticoid-induced muscle cell atrophy. J Cachexia Sarcopenia Muscle 2017; 8:974-990. [PMID: 28675664 PMCID: PMC5700440 DOI: 10.1002/jcsm.12222] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 04/09/2017] [Accepted: 05/22/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Many pathological states characterized by muscle atrophy are associated with an increase in circulating glucocorticoids and poor patient prognosis, making it an important target for treatment. The development of treatments for glucocorticoid-induced and wasting disorder-related skeletal muscle atrophy should be designed based on how the particular transcriptional program is orchestrated and how the balance of muscle protein synthesis and degradation is deregulated. Here, we investigated whether the obestatin/GPR39 system, an autocrine/paracrine signaling system acting on myogenesis and with anabolic effects on the skeletal muscle, could protect against glucocorticoid-induced muscle cell atrophy. METHODS In the present study, we have utilized mouse C2C12 myotube cultures to examine whether the obestatin/GPR39 signaling pathways can affect the atrophy induced by the synthetic glucocorticoid dexamethasone. We have extended these findings to in vitro effects on human atrophy using human KM155C25 myotubes. RESULTS The activation of the obestatin/GPR39 system protects from glucocorticoid-induced atrophy by regulation of Akt, PKD/PKCμ, CAMKII and AMPK signaling and its downstream targets in the control of protein synthesis, ubiquitin-proteasome system and autophagy-lysosome system in mouse cells. We compared mouse and human myotube cells in their response to glucocorticoid and identified differences in both the triggering of the atrophic program and the response to obestatin stimulation. Notably, we demonstrate that specific patterns of post-translational modifications of FoxO4 and FoxO1 play a key role in directing FoxO activity in response to obestatin in human myotubes. CONCLUSIONS Our findings emphasize the function of the obestatin/GPR39 system in coordinating a variety of pathways involved in the regulation of protein degradation during catabolic conditions.
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Affiliation(s)
- Tania Cid‐Díaz
- Área de Endocrinología Molecular y Celular, Instituto de Investigación Sanitaria de Santiago (IDIS)Complejo Hospitalario Universitario de Santiago (CHUS), Servicio Gallego de Salud (SERGAS)Choupana s/n15706Santiago de CompostelaSpain
| | - Icía Santos‐Zas
- Área de Endocrinología Molecular y Celular, Instituto de Investigación Sanitaria de Santiago (IDIS)Complejo Hospitalario Universitario de Santiago (CHUS), Servicio Gallego de Salud (SERGAS)Choupana s/n15706Santiago de CompostelaSpain
| | - Jessica González‐Sánchez
- Área de Endocrinología Molecular y Celular, Instituto de Investigación Sanitaria de Santiago (IDIS)Complejo Hospitalario Universitario de Santiago (CHUS), Servicio Gallego de Salud (SERGAS)Choupana s/n15706Santiago de CompostelaSpain
| | - Uxía Gurriarán‐Rodríguez
- Sprott Center for Stem Cell ResearchOttawa Hospital Research Institute501 Smyth RoadOttawaOntarioK1H 8L6Canada
| | - Carlos S. Mosteiro
- Área de Endocrinología Molecular y Celular, Instituto de Investigación Sanitaria de Santiago (IDIS)Complejo Hospitalario Universitario de Santiago (CHUS), Servicio Gallego de Salud (SERGAS)Choupana s/n15706Santiago de CompostelaSpain
| | - Xesús Casabiell
- Departamento de FisiologíaFacultad de Veterinaria, Universidad de Santiago de Compostela (USC)Carballo Calero s/n27002LugoSpain
| | - Tomás García‐Caballero
- Departamento de Ciencias MorfológicasFacultad de Medicina, USCSan Francisco s/n15704Santiago de CompostelaSpain
| | - Vincent Mouly
- Sorbonne Universités, UPMC Université Paris 06, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology47 Boulevard de l'hôpital75013ParisFrance
| | - Yolanda Pazos
- Área de Endocrinología Molecular y Celular, Instituto de Investigación Sanitaria de Santiago (IDIS)Complejo Hospitalario Universitario de Santiago (CHUS), Servicio Gallego de Salud (SERGAS)Choupana s/n15706Santiago de CompostelaSpain
| | - Jesús P. Camiña
- Área de Endocrinología Molecular y Celular, Instituto de Investigación Sanitaria de Santiago (IDIS)Complejo Hospitalario Universitario de Santiago (CHUS), Servicio Gallego de Salud (SERGAS)Choupana s/n15706Santiago de CompostelaSpain
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24
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Kobayashi T, Mattarollo SR. Natural killer cell metabolism. Mol Immunol 2017; 115:3-11. [PMID: 29179986 DOI: 10.1016/j.molimm.2017.11.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/16/2017] [Accepted: 11/20/2017] [Indexed: 12/24/2022]
Abstract
Natural killer (NK) cells are a critical component in the innate immune response against disease. NK cell function is tightly regulated by specific cytokine and activation/inhibitory receptor signalling, leading to diverse effector responses. Like all living cells, energy metabolism is a fundamental requirement for NK cell activation and survival. There is growing evidence that distinct functional profiles of NK cells are determined by alterations to cellular metabolic pathways. In this review, we summarise current literature that has explored NK cell metabolism to provide insight into how metabolic regulation controls NK cell function. We focus on metabolism pathways induced by different NK cell stimuli, metabolic regulatory proteins, and nutrient and hormonal levels in health and disease which impact on NK cell metabolic and functional activity.
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Affiliation(s)
- Takumi Kobayashi
- The University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane 4102, Queensland, Australia
| | - Stephen R Mattarollo
- The University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane 4102, Queensland, Australia.
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25
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Gu X, Yan Y, Novick SJ, Kovach A, Goswami D, Ke J, Tan MHE, Wang L, Li X, de Waal PW, Webb MR, Griffin PR, Xu HE, Melcher K. Deconvoluting AMP-activated protein kinase (AMPK) adenine nucleotide binding and sensing. J Biol Chem 2017; 292:12653-12666. [PMID: 28615457 PMCID: PMC5535039 DOI: 10.1074/jbc.m117.793018] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 05/31/2017] [Indexed: 12/16/2022] Open
Abstract
AMP-activated protein kinase (AMPK) is a central cellular energy sensor that adapts metabolism and growth to the energy state of the cell. AMPK senses the ratio of adenine nucleotides (adenylate energy charge) by competitive binding of AMP, ADP, and ATP to three sites (CBS1, CBS3, and CBS4) in its γ-subunit. Because these three binding sites are functionally interconnected, it remains unclear how nucleotides bind to individual sites, which nucleotides occupy each site under physiological conditions, and how binding to one site affects binding to the other sites. Here, we comprehensively analyze nucleotide binding to wild-type and mutant AMPK protein complexes by quantitative competition assays and by hydrogen-deuterium exchange MS. We also demonstrate that NADPH, in addition to the known AMPK ligand NADH, directly and competitively binds AMPK at the AMP-sensing CBS3 site. Our findings reveal how AMP binding to one site affects the conformation and adenine nucleotide binding at the other two sites and establish CBS3, and not CBS1, as the high affinity exchangeable AMP/ADP/ATP-binding site. We further show that AMP binding at CBS4 increases AMP binding at CBS3 by 2 orders of magnitude and reverses the AMP/ATP preference of CBS3. Together, these results illustrate how the three CBS sites collaborate to enable highly sensitive detection of cellular energy states to maintain the tight ATP homeostastis required for cellular metabolism.
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Affiliation(s)
- Xin Gu
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - Yan Yan
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503; VARI-SIMM Center, Center for Structure and Function of Drug Targets, The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai 201203, China
| | - Scott J Novick
- Department of Molecular Medicine, Translational Research Institute, The Scripps Research Institute, Jupiter, Florida 33458
| | - Amanda Kovach
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - Devrishi Goswami
- Department of Molecular Medicine, Translational Research Institute, The Scripps Research Institute, Jupiter, Florida 33458
| | - Jiyuan Ke
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - M H Eileen Tan
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503; The Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Lili Wang
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - Xiaodan Li
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - Parker W de Waal
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503
| | - Martin R Webb
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Patrick R Griffin
- Department of Molecular Medicine, Translational Research Institute, The Scripps Research Institute, Jupiter, Florida 33458
| | - H Eric Xu
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503; VARI-SIMM Center, Center for Structure and Function of Drug Targets, The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai 201203, China
| | - Karsten Melcher
- Laboratories of Structural Sciences and Structural Biology and Biochemistry, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan 49503.
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26
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López M. EJE PRIZE 2017: Hypothalamic AMPK: a golden target against obesity? Eur J Endocrinol 2017; 176:R235-R246. [PMID: 28232370 PMCID: PMC5425938 DOI: 10.1530/eje-16-0927] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 01/26/2017] [Accepted: 02/22/2017] [Indexed: 12/16/2022]
Abstract
AMP-activated protein kinase (AMPK) is a cellular gauge that is activated under conditions, such as low energy, increasing energy production and reducing energy waste. Centrally, the AMPK pathway is a canonical route regulating energy homeostasis, by integrating peripheral signals, such as hormones and metabolites, with neuronal networks. Current evidence links hypothalamic AMPK with feeding, brown adipose tissue (BAT) thermogenesis and browning of white adipose tissue (WAT), as well as muscle metabolism, hepatic function and glucose homeostasis. The relevance of these data is interesting from a therapeutic point of view as several agents with potential anti-obesity and/or antidiabetic effects, some currently in clinical use, such as nicotine, metformin and liraglutide are known to act through AMPK, either peripherally or centrally. Furthermore, the orexigenic and weight-gaining effects of the worldwide use of antipsychotic drugs (APDs), such as olanzapine, are also mediated by hypothalamic AMPK. Overall, this evidence makes hypothalamic AMPK signaling an interesting target for the drug development, with its potential for controlling both sides of the energy balance equation, namely feeding and energy expenditure through defined metabolic pathways.
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Affiliation(s)
- Miguel López
- Department of PhysiologyNeurObesity Group, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria and CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain
- Correspondence should be addressed to M López;
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Li J, Li S, Wang F, Xin F. Structural and biochemical insights into the allosteric activation mechanism of AMP-activated protein kinase. Chem Biol Drug Des 2016; 89:663-669. [PMID: 27809416 DOI: 10.1111/cbdd.12897] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/11/2016] [Accepted: 10/23/2016] [Indexed: 12/12/2022]
Abstract
The AMP-activated protein kinase (AMPK), a complicated αβγ heterotrimer, can sense cellular energy status and maintain energy homeostasis via switching catabolic and anabolic pathways. AMPK also participates in the regulation of many other life activities, including the cell cycle, cell polarity, autophagy, and life span. Therefore, AMPK is widely studied as a potential drug target for treatment of type 2 diabetes and some other metabolic diseases, cancers, and cardiovascular diseases. Similar to other kinases, the phosphorylation of α-Thr172 in the activation loop by upstream kinases is crucial for the activation of AMPK. In addition, the binding of AMP and its analogues to the γ subunit causes further allosteric activation, which makes AMPK distinctive from other kinases. Here, we give a brief introduction to the domain constitutions of mammalian AMPK and then systematically review its allosteric activation mechanism from a structural and biochemical view.
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Affiliation(s)
- Jin Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Shuying Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Fengzhong Wang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Fengjiao Xin
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
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Prantner D, Perkins DJ, Vogel SN. AMP-activated Kinase (AMPK) Promotes Innate Immunity and Antiviral Defense through Modulation of Stimulator of Interferon Genes (STING) Signaling. J Biol Chem 2016; 292:292-304. [PMID: 27879319 DOI: 10.1074/jbc.m116.763268] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 11/15/2016] [Indexed: 11/06/2022] Open
Abstract
The host protein Stimulator of Interferon Genes (STING) has been shown to be essential for recognition of both viral and intracellular bacterial pathogens, but its regulation remains unclear. Previously, we reported that mitochondrial membrane potential regulates STING-dependent IFN-β induction independently of ATP synthesis. Because mitochondrial membrane potential controls calcium homeostasis, and AMP-activated protein kinase (AMPK) is regulated, in part, by intracellular calcium, we postulated that AMPK participates in STING activation; however, its role has yet to be been defined. Addition of an intracellular calcium chelator or an AMPK inhibitor to either mouse macrophages or mouse embryonic fibroblasts (MEFs) suppressed IFN-β and TNF-α induction following stimulation with the STING-dependent ligand 5,6-dimethyl xanthnone-4-acetic acid (DMXAA). These pharmacological findings were corroborated by showing that MEFs lacking AMPK activity also failed to up-regulate IFN-β and TNF-α after treatment with DMXAA or the natural STING ligand cyclic GMP-AMP (cGAMP). As a result, AMPK-deficient MEFs exhibit impaired control of vesicular stomatitis virus (VSV), a virus sensed by STING that can cause an influenza-like illness in humans. This impairment could be overcome by pretreatment of AMPK-deficient MEFs with type I IFN, illustrating that de novo production of IFN-β in response to VSV plays a key role in antiviral defense during infection. Loss of AMPK also led to dephosphorylation at Ser-555 of the known STING regulator, UNC-51-like kinase 1 (ULK1). However, ULK1-deficient cells responded normally to DMXAA, indicating that AMPK promotes STING-dependent signaling independent of ULK1 in mouse cells.
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Affiliation(s)
- Daniel Prantner
- From the Department of Microbiology and Immunology, University of Maryland, School of Medicine, Baltimore, Maryland 21201
| | - Darren J Perkins
- From the Department of Microbiology and Immunology, University of Maryland, School of Medicine, Baltimore, Maryland 21201
| | - Stefanie N Vogel
- From the Department of Microbiology and Immunology, University of Maryland, School of Medicine, Baltimore, Maryland 21201
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Barabutis N, Verin A, Catravas JD. Regulation of pulmonary endothelial barrier function by kinases. Am J Physiol Lung Cell Mol Physiol 2016; 311:L832-L845. [PMID: 27663990 DOI: 10.1152/ajplung.00233.2016] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/15/2016] [Indexed: 12/15/2022] Open
Abstract
The pulmonary endothelium is the target of continuous physiological and pathological stimuli that affect its crucial barrier function. The regulation, defense, and repair of endothelial barrier function require complex biochemical processes. This review examines the role of endothelial phosphorylating enzymes, kinases, a class with profound, interdigitating influences on endothelial permeability and lung function.
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Affiliation(s)
- Nektarios Barabutis
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia
| | - Alexander Verin
- Vascular Biology Center, Augusta University, Augusta, Georgia; and
| | - John D Catravas
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, .,School of Medical Diagnostic and Translational Sciences, College of Health Sciences, Old Dominion University, Norfolk, Virginia
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López M, Nogueiras R, Tena-Sempere M, Diéguez C. Hypothalamic AMPK: a canonical regulator of whole-body energy balance. Nat Rev Endocrinol 2016; 12:421-32. [PMID: 27199291 DOI: 10.1038/nrendo.2016.67] [Citation(s) in RCA: 211] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
AMP-activated protein kinase (AMPK) has a major role in the modulation of energy balance. AMPK is activated in conditions of low energy, increasing energy production and reducing energy consumption. The AMPK pathway is a canonical route regulating energy homeostasis by integrating peripheral signals, such as hormones and metabolites, with neuronal networks. Current evidence has implicated AMPK in the hypothalamus and hindbrain with feeding, brown adipose tissue thermogenesis and browning of white adipose tissue, through modulation of the sympathetic nervous system, as well as glucose homeostasis. Interestingly, several potential antiobesity and/or antidiabetic agents, some of which are currently in clinical use such as metformin and liraglutide, exert some of their actions by acting on AMPK. Furthermore, the orexigenic and weight-gain effects of commonly used antipsychotic drugs are also mediated by hypothalamic AMPK. Overall, this evidence suggests that hypothalamic AMPK signalling is an interesting target for drug development, but is this approach feasible? In this Review we discuss the current understanding of hypothalamic AMPK and its role in the central regulation of energy balance and metabolism.
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Affiliation(s)
- Miguel López
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, 15706, Spain
| | - Rubén Nogueiras
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, 15706, Spain
| | - Manuel Tena-Sempere
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, 15706, Spain
- Department of Cell Biology, Physiology and Immunology, University of Córdoba; Instituto Maimónides de Investigación Biomédica (IMIBIC)/Hospital Reina Sofía, 14004 Córdoba, Spain
- FiDiPro Program, Department of Physiology, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland
| | - Carlos Diéguez
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, 15706, Spain
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Richards L, Li M, van Esch B, Garssen J, Folkerts G. The effects of short-chain fatty acids on the cardiovascular system. PHARMANUTRITION 2016. [DOI: 10.1016/j.phanu.2016.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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AMPK Regulation of Cell Growth, Apoptosis, Autophagy, and Bioenergetics. EXPERIENTIA SUPPLEMENTUM (2012) 2016; 107:45-71. [PMID: 27812976 DOI: 10.1007/978-3-319-43589-3_3] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In eukaryotic cells, AMP-activated protein kinase (AMPK) generally promotes catabolic pathways that produce ATP and at the same time inhibits anabolic pathways involved in different processes that consume ATP. As an energy sensor, AMPK is involved in the main cellular functions implicated in cell fate, such as cell growth and autophagy.Recently, AMPK has been connected with apoptosis regulation, although the molecular mechanism by which AMPK induces and/or inhibits cell death is not clear.This chapter reviews the essential role of AMPK in signaling pathways that respond to cellular stress and damage, highlighting the complex and reciprocal regulation between AMPK and their targets and effectors. The therapeutic implications of the role of AMPK in different pathologies such as diabetes, cancer, or mitochondrial dysfunctions are still controversial, and it is necessary to further investigate the molecular mechanisms underlying AMPK activation.
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Grahame Hardie D. Regulation of AMP-activated protein kinase by natural and synthetic activators. Acta Pharm Sin B 2016; 6:1-19. [PMID: 26904394 PMCID: PMC4724661 DOI: 10.1016/j.apsb.2015.06.002] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 05/28/2015] [Indexed: 12/11/2022] Open
Abstract
The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status that is almost universally expressed in eukaryotic cells. While it appears to have evolved in single-celled eukaryotes to regulate energy balance in a cell-autonomous manner, during the evolution of multicellular animals its role has become adapted so that it also regulates energy balance at the whole body level, by responding to hormones that act primarily on the hypothalamus. AMPK monitors energy balance at the cellular level by sensing the ratios of AMP/ATP and ADP/ATP, and recent structural analyses of the AMPK heterotrimer that have provided insight into the complex mechanisms for these effects will be discussed. Given the central importance of energy balance in diseases that are major causes of morbidity or death in humans, such as type 2 diabetes, cancer and inflammatory disorders, there has been a major drive to develop pharmacological activators of AMPK. Many such activators have been described, and the various mechanisms by which these activate AMPK will be discussed. A particularly large class of AMPK activators are natural products of plants derived from traditional herbal medicines. While the mechanism by which most of these activate AMPK has not yet been addressed, I will argue that many of them may be defensive compounds produced by plants to deter infection by pathogens or grazing by insects or herbivores, and that many of them will turn out to be inhibitors of mitochondrial function.
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Affiliation(s)
- David Grahame Hardie
- Division of Cell Signaling & Immunology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
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34
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Regulation of Carbohydrate Metabolism, Lipid Metabolism, and Protein Metabolism by AMPK. EXPERIENTIA SUPPLEMENTUM (2012) 2016; 107:23-43. [PMID: 27812975 DOI: 10.1007/978-3-319-43589-3_2] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This chapter summarizes AMPK function in the regulation of substrate and energy metabolism with the main emphasis on carbohydrate and lipid metabolism, protein turnover, mitochondrial biogenesis, and whole-body energy homeostasis. AMPK acts as whole-body energy sensor and integrates different signaling pathway to meet both cellular and body energy requirements while inhibiting energy-consuming processes but also activating energy-producing ones. AMPK mainly promotes glucose and fatty acid catabolism, whereas it prevents protein, glycogen, and fatty acid synthesis.
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Dasgupta B, Chhipa RR. Evolving Lessons on the Complex Role of AMPK in Normal Physiology and Cancer. Trends Pharmacol Sci 2015; 37:192-206. [PMID: 26711141 DOI: 10.1016/j.tips.2015.11.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 02/08/2023]
Abstract
AMP kinase (AMPK) is an evolutionarily conserved enzyme required for adaptive responses to various physiological and pathological conditions. AMPK executes numerous cellular functions, some of which are often perceived at odds with each other. While AMPK is essential for embryonic growth and development, its full impact in adult tissues is revealed under stressful situations that organisms face in the real world. Conflicting reports about its cellular functions, particularly in cancer, are intriguing and a growing number of AMPK activators are being developed to treat human diseases such as cancer and diabetes. Whether these drugs will have only context-specific benefits or detrimental effects in the treatment of human cancer will be a subject of intense research. Here we review the current state of AMPK research with an emphasis on cancer and discuss the yet unresolved context-dependent functions of AMPK in human cancer.
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Affiliation(s)
- Biplab Dasgupta
- Division of Oncology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
| | - Rishi Raj Chhipa
- Division of Oncology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
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36
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Asby D, Cuda F, Beyaert M, Houghton F, Cagampang F, Tavassoli A. AMPK Activation via Modulation of De Novo Purine Biosynthesis with an Inhibitor of ATIC Homodimerization. ACTA ACUST UNITED AC 2015; 22:838-48. [DOI: 10.1016/j.chembiol.2015.06.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 05/28/2015] [Accepted: 06/02/2015] [Indexed: 01/05/2023]
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Abstract
The heart is a very special organ in the body and has a high requirement for metabolism due to its constant workload. As a consequence, to provide a consistent and sufficient energy a high steady-state demand of metabolism is required by the heart. When delicately balanced mechanisms are changed by physiological or pathophysiological conditions, the whole system's homeostasis will be altered to a new balance, which contributes to the pathologic process. So it is no wonder that almost every heart disease is related to metabolic shift. Furthermore, aging is also found to be related to the reduction in mitochondrial function, insulin resistance, and dysregulated intracellular lipid metabolism. Adenosine monophosphate-activated protein kinase (AMPK) functions as an energy sensor to detect intracellular ATP/AMP ratio and plays a pivotal role in intracellular adaptation to energy stress. During different pathology (like myocardial ischemia and hypertension), the activation of cardiac AMPK appears to be essential for repairing cardiomyocyte's function by accelerating ATP generation, attenuating ATP depletion, and protecting the myocardium against cardiac dysfunction and apoptosis. In this overview, we will talk about the normal heart's metabolism, how metabolic shifts during aging and different pathologies, and how AMPK regulates metabolic changes during these conditions.
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Affiliation(s)
- Yina Ma
- Department of Pharmacology and Toxicology, State University of New York at Buffalo, NY 14214
| | - Ji Li
- Department of Pharmacology and Toxicology, State University of New York at Buffalo, NY 14214
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Yong Y, Shin SY, Jung Y, Jung H, Ahn S, Chong Y, Lim Y. Flavonoids activating adenosine monophosphate-activated protein kinase. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/s13765-015-0003-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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39
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Li X, Wang L, Zhou XE, Ke J, de Waal PW, Gu X, Tan MHE, Wang D, Wu D, Xu HE, Melcher K. Structural basis of AMPK regulation by adenine nucleotides and glycogen. Cell Res 2014; 25:50-66. [PMID: 25412657 PMCID: PMC4650587 DOI: 10.1038/cr.2014.150] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 09/02/2014] [Accepted: 09/19/2014] [Indexed: 12/19/2022] Open
Abstract
AMP-activated protein kinase (AMPK) is a central cellular energy sensor and regulator of energy homeostasis, and a promising drug target for the treatment of diabetes, obesity, and cancer. Here we present low-resolution crystal structures of the human α1β2γ1 holo-AMPK complex bound to its allosteric modulators AMP and the glycogen-mimic cyclodextrin, both in the phosphorylated (4.05 Å) and non-phosphorylated (4.60 Å) state. In addition, we have solved a 2.95 Å structure of the human kinase domain (KD) bound to the adjacent autoinhibitory domain (AID) and have performed extensive biochemical and mutational studies. Together, these studies illustrate an underlying mechanism of allosteric AMPK modulation by AMP and glycogen, whose binding changes the equilibria between alternate AID (AMP) and carbohydrate-binding module (glycogen) interactions.
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Affiliation(s)
- Xiaodan Li
- 1] Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China [2] School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China [3] Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
| | - Lili Wang
- 1] Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China [2] School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China [3] Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
| | - X Edward Zhou
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
| | - Jiyuan Ke
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
| | - Parker W de Waal
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
| | - Xin Gu
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
| | - M H Eileen Tan
- 1] Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA [2] Department of Obstetrics & Gynecology, National University Hospital, Yong Loo Lin School of Medicine, National University of Singapore, 119074, Singapore
| | - Dongye Wang
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China
| | - Donghai Wu
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China
| | - H Eric Xu
- 1] Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA [2] VARI/SIMM Center, CAS-Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Karsten Melcher
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave, NE, Grand Rapids, MI 49503, USA
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40
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Affiliation(s)
- Miguel López
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain.
| | - Carlos Diéguez
- Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, 15782, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), 15706, Spain.
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41
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Abstract
Adenosine monophosphate-activated protein kinase (AMPK) is a serine/threonine kinase that is crucial for cellular energy metabolism homeostasis. AMPK monitors cellular energy status in response to nutritional variations and, once activated by low energy status, switches on ATP-producing catabolic pathways and switches off ATP-consuming anabolic pathways to restore cellular energy homeostasis. When T lymphocytes encounter foreign antigens, they initiate a program of differentiation leading to the rapid generation of effector and memory cells that clear the pathogen and prevent future infection, respectively. Differentiation of naïve T cells in effector or long term memory cells is tightly associated with changes in their energy metabolic activity and recent data have revealed that fine-tuning of metabolism could modulate T cell functions. Here, we will review recent data about the regulation of T cell metabolism by AMPK and discuss its influence on T cell function.
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Affiliation(s)
- Fabienne Andris
- Laboratoire d'Immunobiologie, Institut de Biologie et de Médecine Moléculaire, Université Libre de Bruxelles, Gosselies, Belgium
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Amato S, Man HY. AMPK links cellular bioenergy status to the decision making of axon initiation in neurons. CELLULAR LOGISTICS 2014; 1:103-105. [PMID: 21922074 DOI: 10.4161/cl.1.3.16815] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 07/01/2011] [Accepted: 07/06/2011] [Indexed: 01/20/2023]
Abstract
Neuronal polarization begins by the selection of a single minor neurite that subsequently undergoes rapid extension until reaching a formidable length. To ensure that the highly active growth can be sustained by a sufficient energy supply, neurons are supposed to sense their energy status prior to initiating polarization. Our recent work shows that the bioenergy sensor, AMPK, plays a crucial role in the regulation of axon initiation. Activation of AMPK to mimic energy-lacking conditions results in a halt in axon selection and growth, leading to a loss of neuronal polarization.
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Affiliation(s)
- Stephen Amato
- Department of Biology; Boston University; Boston, MA USA
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43
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Abstract
AMPK (AMP-activated protein kinase) is a cellular energy sensor that monitors the ratio of AMP/ATP, and possibly also ADP/ATP, inside cells. Once activated by falling cellular energy levels, it acts to restore energy homoeostasis by switching on catabolic pathways that generate ATP, while switching off anabolic pathways and other processes consuming ATP. AMPK is switched on by increases in AMP via three mechanisms, all of which are antagonized by ATP: (i) promotion of phosphorylation of Thr172 by upstream activating kinases; (ii) inhibition of dephosphorylation of Thr172 by phosphatases; and (iii) allosteric activation of the phosphorylated kinase. Recently, it has been proposed that the first two mechanisms are also triggered by ADP, which might be the physiological signal rather than AMP, and that the third mechanism may not be physiologically significant. We have re-evaluated these questions, and found that only mechanism (ii) is mimicked by ADP, and that ADP is also less potent than AMP, which we still believe to be the primary signal. We have also provided evidence that mechanism (iii), i.e. allosteric activation by AMP, is a quantitatively significant mechanism in intact cells.
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44
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Abstract
The adenosine monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway arose early during evolution of eukaryotic cells, when it appears to have been involved in the response to glucose starvation and perhaps also in monitoring the output of the newly acquired mitochondria. Due to the advent of hormonal regulation of glucose homeostasis, glucose starvation is a less frequent event for mammalian cells than for single-celled eukaryotes. Nevertheless, the AMPK system has been preserved in mammals where, by monitoring cellular AMP:adenosine triphosphate (ATP) and adenosine diphosphate (ADP):ATP ratios and balancing the rates of catabolism and ATP consumption, it maintains energy homeostasis at a cell-autonomous level. In addition, hormones involved in maintaining energy balance at the whole-body level interact with AMPK in the hypothalamus. AMPK is activated by two widely used clinical drugs, metformin and aspirin, and also by many natural products of plants that are either derived from traditional medicines or are promoted as "nutraceuticals."
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Affiliation(s)
- D Grahame Hardie
- Division of Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, United Kingdom;
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45
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Schaeffer PJ, Lindstedt SL. How animals move: comparative lessons on animal locomotion. Compr Physiol 2013; 3:289-314. [PMID: 23720288 DOI: 10.1002/cphy.c110059] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Comparative physiology often provides unique insights in animal structure and function. It is specifically through this lens that we discuss the fundamental properties of skeletal muscle and animal locomotion, incorporating variation in body size and evolved difference among species. For example, muscle frequencies in vivo are highly constrained by body size, which apparently tunes muscle use to maximize recovery of elastic recoil potential energy. Secondary to this constraint, there is an expected linking of skeletal muscle structural and functional properties. Muscle is relatively simple structurally, but by changing proportions of the few muscle components, a diverse range of functional outputs is possible. Thus, there is a consistent and predictable relation between muscle function and myocyte composition that illuminates animal locomotion. When animals move, the mechanical properties of muscle diverge from the static textbook force-velocity relations described by A. V. Hill, as recovery of elastic potential energy together with force and power enhancement with activation during stretch combine to modulate performance. These relations are best understood through the tool of work loops. Also, when animals move, locomotion is often conveniently categorized energetically. Burst locomotion is typified by high-power outputs and short durations while sustained, cyclic, locomotion engages a smaller fraction of the muscle tissue, yielding lower force and power. However, closer examination reveals that rather than a dichotomy, energetics of locomotion is a continuum. There is a remarkably predictable relationship between duration of activity and peak sustainable performance.
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46
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Serra D, Mera P, Malandrino MI, Mir JF, Herrero L. Mitochondrial fatty acid oxidation in obesity. Antioxid Redox Signal 2013; 19:269-84. [PMID: 22900819 PMCID: PMC3691913 DOI: 10.1089/ars.2012.4875] [Citation(s) in RCA: 163] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
SIGNIFICANCE Current lifestyles with high-energy diets and little exercise are triggering an alarming growth in obesity. Excess of adiposity is leading to severe increases in associated pathologies, such as insulin resistance, type 2 diabetes, atherosclerosis, cancer, arthritis, asthma, and hypertension. This, together with the lack of efficient obesity drugs, is the driving force behind much research. RECENT ADVANCES Traditional anti-obesity strategies focused on reducing food intake and increasing physical activity. However, recent results suggest that enhancing cellular energy expenditure may be an attractive alternative therapy. CRITICAL ISSUES This review evaluates recent discoveries regarding mitochondrial fatty acid oxidation (FAO) and its potential as a therapy for obesity. We focus on the still controversial beneficial effects of increased FAO in liver and muscle, recent studies on how to potentiate adipose tissue energy expenditure, and the different hypotheses involving FAO and the reactive oxygen species production in the hypothalamic control of food intake. FUTURE DIRECTIONS The present review aims to provide an overview of novel anti-obesity strategies that target mitochondrial FAO and that will definitively be of high interest in the future research to fight against obesity-related disorders.
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Affiliation(s)
- Dolors Serra
- Department of Biochemistry and Molecular Biology, Facultat de Farmàcia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona IBUB, Barcelona, Spain
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Hardie DG, Alessi DR. LKB1 and AMPK and the cancer-metabolism link - ten years after. BMC Biol 2013; 11:36. [PMID: 23587167 PMCID: PMC3626889 DOI: 10.1186/1741-7007-11-36] [Citation(s) in RCA: 239] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 04/11/2013] [Indexed: 12/17/2022] Open
Abstract
The identification of a complex containing the tumor suppressor LKB1 as the critical upstream kinase required for the activation of AMP-activated protein kinase (AMPK) by metabolic stress was reported in an article in Journal of Biology in 2003. This finding represented the first clear link between AMPK and cancer. Here we briefly discuss how this discovery came about, and describe some of the insights, especially into the role of AMPK in cancer, that have followed from it.
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Affiliation(s)
- D Grahame Hardie
- Division of Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK
| | - Dario R Alessi
- MRC Protein Phosphorylation Unit, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK
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Liu J, Zhang JF, Lu JZ, Zhang DL, Li K, Su K, Wang J, Zhang YM, Wang N, Yang ST, Bu L, Ou-yang JP. Astragalus polysaccharide stimulates glucose uptake in L6 myotubes through AMPK activation and AS160/TBC1D4 phosphorylation. Acta Pharmacol Sin 2013; 34:137-45. [PMID: 23103623 DOI: 10.1038/aps.2012.133] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
AIM To establish the mechanism responsible for the stimulation of glucose uptake by Astragalus polysaccharide (APS), extracted from Astragalus membranaceus Bunge, in L6 myotubes in vitro. METHODS APS-stimulated glucose uptake in L6 myotubes was measured using the 2-deoxy-[(3)H]-D-glucose method. The adenine nucleotide contents in the cells were measured by HPLC. The phosphorylation of AMP-activated protein kinase (AMPK) and Akt substrate of 160 kDa (AS160) was examined using Western blot analysis. The cells transfected with 4P mutant AS160 (AS160-4P) were constructed using gene transfer approach. RESULTS Treatment of L6 myotubes with APS (100-1600 μg/mL) significantly increased glucose uptake in time- and concentration-dependent manners. The maximal glucose uptake was reached in the cells treated with APS (400 μg/mL) for 36 h. The APS-stimulated glucose uptake was significantly attenuated by pretreatment with Compound C, a selective AMPK inhibitor or in the cells overexpressing AS160-4P. Treatment of L6 myotubes with APS strongly promoted the activation of AMPK. We further demonstrated that either Ca(2+)/calmodulin-dependent protein kinase kinase β (CaMKKβ) or liver kinase B1 (LKB1) mediated APS-induced activation of AMPK in L6 myotubes, and the increased cellular AMP: ATP ratio was also involved. Treatment of L6 myotubes with APS robustly enhanced the phosphorylation of AS160, which was significantly attenuated by pretreatment with Compound C. CONCLUSION Our results demonstrate that APS stimulates glucose uptake in L6 myotubes through the AMP-AMPK-AS160 pathway, which may contribute to its hypoglycemic effect.
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Abstract
AMP-activated protein kinase (AMPK) is a stress-activated kinase that functions as a cellular fuel gauge and master metabolic regulator. Recent investigation has elucidated novel molecular mechanisms of AMPK regulation and important biological actions of the AMPK pathway that are highly relevant to cardiovascular disease. Activation of the intrinsic AMPK pathway plays an important role in the myocardial response to ischemia, pressure overload, and heart failure. Pharmacological activation of AMPK shows promise as a therapeutic strategy in the treatment of heart disease. The purpose of this review is to assess how recent discoveries have extended and in some cases challenged existing paradigms, providing new insights into the regulation of AMPK, its diverse biological actions, and therapeutic potential in the heart.
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Affiliation(s)
- Vlad G Zaha
- Department of Internal Medicine, Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Yale School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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Blagih J, Krawczyk CM, Jones RG. LKB1 and AMPK: central regulators of lymphocyte metabolism and function. Immunol Rev 2012; 249:59-71. [DOI: 10.1111/j.1600-065x.2012.01157.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
| | - Connie M. Krawczyk
- Department of Microbiology and Immunology; McGill University; Montreal; Quebec
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