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Rider MH, Vertommen D, Johanns M. How mass spectrometry can be exploited to study AMPK. Essays Biochem 2024:EBC20240009. [PMID: 39056150 DOI: 10.1042/ebc20240009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/12/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024]
Abstract
AMP-activated protein kinase (AMPK) is a key regulator of metabolism and a recognised target for the treatment of metabolic diseases such as Type 2 diabetes (T2D). Here, we review how mass spectrometry (MS) can be used to study short-term control by AMPK via protein phosphorylation and long-term control due to changes in protein expression. We discuss how MS can quantify AMPK subunit levels in tissues from different species. We propose hydrogen-deuterium exchange (HDX)-MS to investigate molecular mechanisms of AMPK activation and thermoproteomic profiling (TPP) to assess off-target effects of pharmacological AMPK activators/inhibitors. Lastly, because large MS data sets are generated, we consider different approaches that can be used for their interpretation.
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Affiliation(s)
- Mark H Rider
- Protein Phosphorylation (PHOS) laboratory, Université catholique de Louvain and de Duve Institute, Avenue Hippocrate 75, B-1200 Brussels, Belgium
| | - Didier Vertommen
- Protein Phosphorylation (PHOS) laboratory, Université catholique de Louvain and de Duve Institute, Avenue Hippocrate 75, B-1200 Brussels, Belgium
| | - Manuel Johanns
- Protein Phosphorylation (PHOS) laboratory, Université catholique de Louvain and de Duve Institute, Avenue Hippocrate 75, B-1200 Brussels, Belgium
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2
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Vidović A, Dolinar K, Chibalin AV, Pirkmajer S. AMPK and glucose deprivation exert an isoform-specific effect on the expression of Na +,K +-ATPase subunits in cultured myotubes. J Muscle Res Cell Motil 2024:10.1007/s10974-024-09673-9. [PMID: 38709429 DOI: 10.1007/s10974-024-09673-9] [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: 01/31/2024] [Accepted: 04/24/2024] [Indexed: 05/07/2024]
Abstract
In skeletal muscle, Na+,K+-ATPase (NKA), a heterodimeric (α/β) P-type ATPase, has an essential role in maintenance of Na+ and K+ homeostasis, excitability, and contractility. AMP-activated protein kinase (AMPK), an energy sensor, increases the membrane abundance and activity of NKA in L6 myotubes, but its potential role in regulation of NKA content in skeletal muscle, which determines maximum capacity for Na+ and K+ transport, has not been clearly delineated. We examined whether energy stress and/or AMPK affect expression of NKA subunits in rat L6 and primary human myotubes. Energy stress, induced by glucose deprivation, increased protein content of NKAα1 and NKAα2 in L6 myotubes, while decreasing the content of NKAα1 in human myotubes. Pharmacological AMPK activators (AICAR, A-769662, and diflunisal) modulated expression of NKA subunits, but their effects only partially mimicked those that occurred in response to glucose deprivation, indicating that AMPK does not mediate all effects of energy stress on NKA expression. Gene silencing of AMPKα1/α2 increased protein levels of NKAα1 in L6 myotubes and NKAα1 mRNA levels in human myotubes, while decreasing NKAα2 protein levels in L6 myotubes. Collectively, our results suggest a role for energy stress and AMPK in modulation of NKA expression in skeletal muscle. However, their modulatory effects were not conserved between L6 myotubes and primary human myotubes, which suggests that coupling between energy stress, AMPK, and regulation of NKA expression in vitro depends on skeletal muscle cell model.
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Affiliation(s)
- Anja Vidović
- Faculty of Medicine, Institute of Pathophysiology, University of Ljubljana, Ljubljana, Slovenia
| | - Klemen Dolinar
- Faculty of Medicine, Institute of Pathophysiology, University of Ljubljana, Ljubljana, Slovenia
| | - Alexander V Chibalin
- Department of Molecular Medicine and Surgery, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
- National Research Tomsk State University, Tomsk, Russia
| | - Sergej Pirkmajer
- Faculty of Medicine, Institute of Pathophysiology, University of Ljubljana, Ljubljana, Slovenia.
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Achanta LB, Thomas DS, Housley GD, Rae CD. AMP-activated protein kinase activators have compound and concentration-specific effects on brain metabolism. J Neurochem 2024; 168:677-692. [PMID: 36977628 DOI: 10.1111/jnc.15815] [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: 01/26/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023]
Abstract
AMP-activated protein kinase (AMPK) is a key sensor of energy balance playing important roles in the balancing of anabolic and catabolic activities. The high energy demands of the brain and its limited capacity to store energy indicate that AMPK may play a significant role in brain metabolism. Here, we activated AMPK in guinea pig cortical tissue slices, both directly with A769662 and PF 06409577 and indirectly with AICAR and metformin. We studied the resultant metabolism of [1-13C]glucose and [1,2-13C]acetate using NMR spectroscopy. We found distinct activator concentration-dependent effects on metabolism, which ranged from decreased metabolic pool sizes at EC50 activator concentrations with no expected stimulation in glycolytic flux to increased aerobic glycolysis and decreased pyruvate metabolism with certain activators. Further, activation with direct versus indirect activators produced distinct metabolic outcomes at both low (EC50) and higher (EC50 × 10) concentrations. Specific direct activation of β1-containing AMPK isoforms with PF 06409577 resulted in increased Krebs cycle activity, restoring pyruvate metabolism while A769662 increased lactate and alanine production, as well as labelling of citrate and glutamine. These results reveal a complex metabolic response to AMPK activators in brain beyond increased aerobic glycolysis and indicate that further research is warranted into their concentration- and mechanism-dependent impact.
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Affiliation(s)
- Lavanya B Achanta
- Neuroscience Research Australia, Barker St, Randwick, New South Wales, 2031, Australia
- Translational Neuroscience Facility, School of Biomedical Sciences, UNSW, Sydney, New South Wales, 2052, Australia
| | - Donald S Thomas
- Mark Wainwright Analytical Centre, UNSW, Sydney, New South Wales, 2052, Australia
| | - Gary D Housley
- Translational Neuroscience Facility, School of Biomedical Sciences, UNSW, Sydney, New South Wales, 2052, Australia
| | - Caroline D Rae
- Neuroscience Research Australia, Barker St, Randwick, New South Wales, 2031, Australia
- School of Psychology, UNSW, Sydney, New South Wales, 2052, Australia
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4
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Oh E, Lee J, Cho S, Kim SW, Won K, Shin WS, Gwak SH, Ha J, Jeon SY, Park JH, Song IS, Thoudam T, Lee IK, Kim S, Choi SY, Kim KT. Gossypetin Prevents the Progression of Nonalcoholic Steatohepatitis by Regulating Oxidative Stress and AMP-Activated Protein Kinase. Mol Pharmacol 2023; 104:214-229. [PMID: 37595967 DOI: 10.1124/molpharm.123.000675] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 07/22/2023] [Accepted: 07/25/2023] [Indexed: 08/20/2023] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is a severe liver metabolic disorder, however, there are still no effective and safe drugs for its treatment. Previous clinical trials used various therapeutic approaches to target individual pathologic mechanisms, but these approaches were unsuccessful because of the complex pathologic causes of NASH. Combinatory therapy in which two or more drugs are administered simultaneously to patients with NASH, however, carries the risk of side effects associated with each individual drug. To solve this problem, we identified gossypetin as an effective dual-targeting agent that activates AMP-activated protein kinase (AMPK) and decreases oxidative stress. Administration of gossypetin decreased hepatic steatosis, lobular inflammation and liver fibrosis in the liver tissue of mice with choline-deficient high-fat diet and methionine-choline deficient diet (MCD) diet-induced NASH. Gossypetin functioned directly as an antioxidant agent, decreasing hydrogen peroxide and palmitate-induced oxidative stress in the AML12 cells and liver tissue of MCD diet-fed mice without regulating the antioxidant response factors. In addition, gossypetin acted as a novel AMPK activator by binding to the allosteric drug and metabolite site, which stabilizes the activated structure of AMPK. Our findings demonstrate that gossypetin has the potential to serve as a novel therapeutic agent for nonalcoholic fatty liver disease /NASH. SIGNIFICANCE STATEMENT: This study demonstrates that gossypetin has preventive effect to progression of nonalcoholic steatohepatitis (NASH) as a novel AMP-activated protein kinase (AMPK) activator and antioxidants. Our findings indicate that simultaneous activation of AMPK and oxidative stress using gossypetin has the potential to serve as a novel therapeutic approach for nonalcoholic fatty liver disease /NASH patients.
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Affiliation(s)
- Eunji Oh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Jae Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Sungji Cho
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Sung Wook Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Kyung Won
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Won Sik Shin
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Seung Hee Gwak
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Joohun Ha
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - So Yeon Jeon
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Jin-Hyang Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Im-Sook Song
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Themis Thoudam
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - In-Kyu Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Seonyong Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Se-Young Choi
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
| | - Kyong-Tai Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang Republic of Korea (E.O., J.L., S.C., S.W.K., K.W.J., W.S.S., S.H.G., K-T.K.); Department of Biochemistry and Molecular Biology, Graduate School, College of Medicine, Kyung Hee University, Seoul, Republic of Korea (J.H.); College of Pharmacy, Dankook University, Cheonan, Republic of Korea (S.Y.J.); College of Pharmacy, Kyungpook National University, Daegu, Republic of Korea (J-H.P., I.-M.S.); Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea (T.T., I.-K.L.); Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea (I.-K.L.); Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Republic of Korea (S.K., S-Y.C.); and Generative Genomics Research Center, Global Green Research & Development Center, Handong Global University, Pohang, Republic of Korea (K.-T.K.)
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5
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AMPK inhibits liver gluconeogenesis: fact or fiction? Biochem J 2023; 480:105-125. [PMID: 36637190 DOI: 10.1042/bcj20220582] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/21/2022] [Accepted: 01/04/2023] [Indexed: 01/14/2023]
Abstract
Is there a role for AMPK in the control of hepatic gluconeogenesis and could targeting AMPK in liver be a viable strategy for treating type 2 diabetes? These are frequently asked questions this review tries to answer. After describing properties of AMPK and different small-molecule AMPK activators, we briefly review the various mechanisms for controlling hepatic glucose production, mainly via gluconeogenesis. The different experimental and genetic models that have been used to draw conclusions about the role of AMPK in the control of liver gluconeogenesis are critically discussed. The effects of several anti-diabetic drugs, particularly metformin, on hepatic gluconeogenesis are also considered. We conclude that the main effect of AMPK activation pertinent to the control of hepatic gluconeogenesis is to antagonize glucagon signalling in the short-term and, in the long-term, to improve insulin sensitivity by reducing hepatic lipid content.
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Tarasiuk O, Miceli M, Di Domizio A, Nicolini G. AMPK and Diseases: State of the Art Regulation by AMPK-Targeting Molecules. BIOLOGY 2022; 11:biology11071041. [PMID: 36101419 PMCID: PMC9312068 DOI: 10.3390/biology11071041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 11/16/2022]
Abstract
5′-adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an enzyme that regulates cellular energy homeostasis, glucose, fatty acid uptake, and oxidation at low cellular ATP levels. AMPK plays an important role in several molecular mechanisms and physiological conditions. It has been shown that AMPK can be dysregulated in different chronic diseases, such as inflammation, diabetes, obesity, and cancer. Due to its fundamental role in physiological and pathological cellular processes, AMPK is considered one of the most important targets for treating different diseases. Over decades, different AMPK targeting compounds have been discovered, starting from those that activate AMPK indirectly by altering intracellular AMP:ATP ratio to compounds that activate AMPK directly by binding to its activation sites. However, indirect altering of intracellular AMP:ATP ratio influences different cellular processes and induces side effects. Direct AMPK activators showed more promising results in eliminating side effects as well as the possibility to engineer drugs for specific AMPK isoforms activation. In this review, we discuss AMPK targeting drugs, especially concentrating on those compounds that activate AMPK by mimicking AMP. These compounds are poorly described in the literature and still, a lot of questions remain unanswered about the exact mechanism of AMP regulation. Future investigation of the mechanism of AMP binding will make it possible to develop new compounds that, in combination with others, can activate AMPK in a synergistic manner.
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Affiliation(s)
- Olga Tarasiuk
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy;
- Correspondence:
| | - Matteo Miceli
- SPILLOproject—Innovative In Silico Solutions for Drug R&D and Pharmacology, 20037 Paderno Dugnano, Italy; (M.M.); (A.D.D.)
| | - Alessandro Di Domizio
- SPILLOproject—Innovative In Silico Solutions for Drug R&D and Pharmacology, 20037 Paderno Dugnano, Italy; (M.M.); (A.D.D.)
| | - Gabriella Nicolini
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy;
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7
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Dai X, Bu X, Gao Y, Guo J, Hu J, Jiang C, Zhang Z, Xu K, Duan J, He S, Zhang J, Wan L, Liu T, Zhou X, Hung MC, Freeman GJ, Wei W. Energy status dictates PD-L1 protein abundance and anti-tumor immunity to enable checkpoint blockade. Mol Cell 2021; 81:2317-2331.e6. [PMID: 33909988 PMCID: PMC8178223 DOI: 10.1016/j.molcel.2021.03.037] [Citation(s) in RCA: 97] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 10/26/2020] [Accepted: 03/22/2021] [Indexed: 02/06/2023]
Abstract
Aberrant energy status contributes to multiple metabolic diseases, including obesity, diabetes, and cancer, but the underlying mechanism remains elusive. Here, we report that ketogenic-diet-induced changes in energy status enhance the efficacy of anti-CTLA-4 immunotherapy by decreasing PD-L1 protein levels and increasing expression of type-I interferon (IFN) and antigen presentation genes. Mechanistically, energy deprivation activates AMP-activated protein kinase (AMPK), which in turn, phosphorylates PD-L1 on Ser283, thereby disrupting its interaction with CMTM4 and subsequently triggering PD-L1 degradation. In addition, AMPK phosphorylates EZH2, which disrupts PRC2 function, leading to enhanced IFNs and antigen presentation gene expression. Through these mechanisms, AMPK agonists or ketogenic diets enhance the efficacy of anti-CTLA-4 immunotherapy and improve the overall survival rate in syngeneic mouse tumor models. Our findings reveal a pivotal role for AMPK in regulating the immune response to immune-checkpoint blockade and advocate for combining ketogenic diets or AMPK agonists with anti-CTLA4 immunotherapy to combat cancer.
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Affiliation(s)
- Xiaoming Dai
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Xia Bu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Yang Gao
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA; Department of Urology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Jianping Guo
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Jia Hu
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Cong Jiang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Zhao Zhang
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Kexin Xu
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Jinzhi Duan
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Shaohui He
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Jinfang Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Lixin Wan
- Department of Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Tianjie Liu
- Department of Urology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Xiaobo Zhou
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mien-Chie Hung
- Graduate Institute of Biomedical Sciences and Center for Molecular Medicine, China Medical University, Taichung 404, Taiwan
| | - Gordon J Freeman
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA.
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8
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Guldbrandsen HO, Staehr C, Iversen NK, Postnov DD, Matchkov VV. Does Src Kinase Mediated Vasoconstriction Impair Penumbral Reperfusion? Stroke 2021; 52:e250-e258. [PMID: 33947213 DOI: 10.1161/strokeaha.120.032737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Despite successful recanalization, a significant number of patients with ischemic stroke experience impaired local brain tissue reperfusion with adverse clinical outcome. The cause and mechanism of this multifactorial complication are yet to be understood. At the current moment, major attention is given to dysfunction in blood-brain barrier and capillary blood flow but contribution of exaggerated constriction of cerebral arterioles has also been suggested. In the brain, arterioles significantly contribute to vascular resistance and thus control of perfusion. Accordingly, pathological changes in arteriolar wall function can, therefore, limit sufficient reperfusion in ischemic stroke, but this has not yet received sufficient attention. Although an increased vascular tone after reperfusion has been demonstrated in several studies, the mechanism behind it remains to be characterized. Importantly, the majority of conventional mechanisms controlling vascular contraction failed to explain elevated cerebrovascular tone after reperfusion. We propose here that the Na,K-ATPase-dependent Src kinase activation are the key mechanisms responsible for elevation of cerebrovascular tone after reperfusion. The Na,K-ATPase, which is essential to control intracellular ion homeostasis, also executes numerous signaling functions. Under hypoxic conditions, the Na,K-ATPase is endocytosed from the membrane of vascular smooth muscle cells. This initiates the Src kinase signaling pathway that sensitizes the contractile machinery to intracellular Ca2+ resulting in hypercontractility of vascular smooth muscle cells and, thus, elevated cerebrovascular tone that can contribute to impaired reperfusion after stroke. This mechanism integrates with cerebral edema that was suggested to underlie impaired reperfusion and is further supported by several studies, which are discussed in this article. However, final demonstration of the molecular mechanism behind Src kinase-associated arteriolar hypercontractility in stroke remains to be done.
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Affiliation(s)
| | - Christian Staehr
- Department of Biomedicine, MEMBRANES, Health (H.O.G., C.S., V.V.M.), Aarhus University, Denmark
| | - Nina Kerting Iversen
- Center of Functionally Integrative Neuroscience, Institute for Clinical Medicine (N.K.I.), Aarhus University, Denmark
| | - Dmitry D Postnov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, Copenhagen University, Denmark (D.D.P.)
| | - Vladimir V Matchkov
- Department of Biomedicine, MEMBRANES, Health (H.O.G., C.S., V.V.M.), Aarhus University, Denmark
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9
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The role of AMPK in regulation of Na +,K +-ATPase in skeletal muscle: does the gauge always plug the sink? J Muscle Res Cell Motil 2021; 42:77-97. [PMID: 33398789 DOI: 10.1007/s10974-020-09594-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 12/14/2020] [Indexed: 12/14/2022]
Abstract
AMP-activated protein kinase (AMPK) is a cellular energy gauge and a major regulator of cellular energy homeostasis. Once activated, AMPK stimulates nutrient uptake and the ATP-producing catabolic pathways, while it suppresses the ATP-consuming anabolic pathways, thus helping to maintain the cellular energy balance under energy-deprived conditions. As much as ~ 20-25% of the whole-body ATP consumption occurs due to a reaction catalysed by Na+,K+-ATPase (NKA). Being the single most important sink of energy, NKA might seem to be an essential target of the AMPK-mediated energy saving measures, yet NKA is vital for maintenance of transmembrane Na+ and K+ gradients, water homeostasis, cellular excitability, and the Na+-coupled transport of nutrients and ions. Consistent with the model that AMPK regulates ATP consumption by NKA, activation of AMPK in the lung alveolar cells stimulates endocytosis of NKA, thus suppressing the transepithelial ion transport and the absorption of the alveolar fluid. In skeletal muscles, contractions activate NKA, which opposes a rundown of transmembrane ion gradients, as well as AMPK, which plays an important role in adaptations to exercise. Inhibition of NKA in contracting skeletal muscle accentuates perturbations in ion concentrations and accelerates development of fatigue. However, different models suggest that AMPK does not inhibit or even stimulates NKA in skeletal muscle, which appears to contradict the idea that AMPK maintains the cellular energy balance by always suppressing ATP-consuming processes. In this short review, we examine the role of AMPK in regulation of NKA in skeletal muscle and discuss the apparent paradox of AMPK-stimulated ATP consumption.
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10
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Alghamdi F, Alshuweishi Y, Salt IP. Regulation of nutrient uptake by AMP-activated protein kinase. Cell Signal 2020; 76:109807. [DOI: 10.1016/j.cellsig.2020.109807] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 02/07/2023]
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11
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Jin K, Ma Y, Manrique-Caballero CL, Li H, Emlet DR, Li S, Baty CJ, Wen X, Kim-Campbell N, Frank A, Menchikova EV, Pastor-Soler NM, Hallows KR, Jackson EK, Shiva S, Pinsky MR, Zuckerbraun BS, Kellum JA, Gómez H. Activation of AMP-activated protein kinase during sepsis/inflammation improves survival by preserving cellular metabolic fitness. FASEB J 2020; 34:7036-7057. [PMID: 32246808 DOI: 10.1096/fj.201901900r] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 01/24/2020] [Accepted: 03/18/2020] [Indexed: 01/08/2023]
Abstract
The purpose was to determine the role of AMPK activation in the renal metabolic response to sepsis, the development of sepsis-induced acute kidney injury (AKI) and on survival. In a prospective experimental study, 167 10- to 12-week-old C57BL/6 mice underwent cecal ligation and puncture (CLP) and human proximal tubule epithelial cells (TEC; HK2) were exposed to inflammatory mix (IM), a combination of lipopolysaccharide (LPS) and high mobility group box 1 (HMGB1). Renal/TEC metabolic fitness was assessed by monitoring the expression of drivers of oxidative phosphorylation (OXPHOS), the rates of utilization of OXPHOS/glycolysis in response to metabolic stress, and mitochondrial function by measuring O2 consumption rates (OCR) and the membrane potential (Δψm ). Sepsis/IM resulted in AKI, increased mortality, and in renal AMPK activation 6-24 hours after CLP/IM. Pharmacologic activation of AMPK with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) or metformin during sepsis improved the survival, while AMPK inhibition with Compound C increased mortality, impaired mitochondrial respiration, decreased OCR, and disrupted TEC metabolic fitness. AMPK-driven protection was associated with increased Sirt 3 expression and restoration of metabolic fitness. Renal AMPK activation in response to sepsis/IM is an adaptive mechanism that protects TEC, organs, and the host by preserving mitochondrial function and metabolic fitness likely through Sirt3 signaling.
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Affiliation(s)
- Kui Jin
- Department of Critical Care, Anhui Provincial Hospital, He Fei, China
| | - Yujie Ma
- Department of Critical Care Medicine, Air Force Medical Center, Beijing, China
| | - Carlos L Manrique-Caballero
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hui Li
- Division of Nephrology and Hypertension and USC/UKRO Kidney Research Center, Department of Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - David R Emlet
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Shengnan Li
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Catherine J Baty
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Xiaoyan Wen
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nahmah Kim-Campbell
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Alicia Frank
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Elizabeth V Menchikova
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nuria M Pastor-Soler
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA.,Division of Nephrology and Hypertension and USC/UKRO Kidney Research Center, Department of Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Kenneth R Hallows
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA.,Division of Nephrology and Hypertension and USC/UKRO Kidney Research Center, Department of Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Sruti Shiva
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA.,Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael R Pinsky
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Brian S Zuckerbraun
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - John A Kellum
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hernando Gómez
- Center for Critical Care Nephrology, Department of Critical Care Medicine, The CRISMA Center, University of Pittsburgh, Pittsburgh, PA, USA.,Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, USA
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12
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Stimulation of Na +/K +-ATPase with an Antibody against Its 4 th Extracellular Region Attenuates Angiotensin II-Induced H9c2 Cardiomyocyte Hypertrophy via an AMPK/SIRT3/PPAR γ Signaling Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:4616034. [PMID: 31636805 PMCID: PMC6766118 DOI: 10.1155/2019/4616034] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 07/09/2019] [Accepted: 08/02/2019] [Indexed: 02/06/2023]
Abstract
Activation of the renin-angiotensin system (RAS) contributes to the pathogenesis of cardiovascular diseases. Sodium potassium ATPase (NKA) expression and activity are often regulated by angiotensin II (Ang II). This study is aimed at investigating whether DR-Ab, an antibody against 4th extracellular region of NKA, can protect Ang II-induced cardiomyocyte hypertrophy. Our results showed that Ang II treatment significantly reduced NKA activity and membrane expression. Pretreatment with DR-Ab preserved cell size in Ang II-induced cardiomyopathy by stabilizing the plasma membrane expression of NKA and restoring its activity. DR-Ab reduced intracellular ROS generation through inhibition of NADPH oxidase activity and protection of mitochondrial functions in Ang II-treated H9c2 cardiomyocytes. Pharmacological manipulation and Western blotting analysis demonstrated the cardioprotective effects were mediated by the activation of the AMPK/Sirt-3/PPARγ signaling pathway. Taken together, our results suggest that dysfunction of NKA is an important mechanism for Ang II-induced cardiomyopathy and DR-Ab may be a novel and promising therapeutic approach to treat cardiomyocyte hypertrophy.
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13
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Collodet C, Foretz M, Deak M, Bultot L, Metairon S, Viollet B, Lefebvre G, Raymond F, Parisi A, Civiletto G, Gut P, Descombes P, Sakamoto K. AMPK promotes induction of the tumor suppressor FLCN through activation of TFEB independently of mTOR. FASEB J 2019; 33:12374-12391. [PMID: 31404503 PMCID: PMC6902666 DOI: 10.1096/fj.201900841r] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
AMPK is a central regulator of energy homeostasis. AMPK not only elicits acute metabolic responses but also promotes metabolic reprogramming and adaptations in the long-term through regulation of specific transcription factors and coactivators. We performed a whole-genome transcriptome profiling in wild-type (WT) and AMPK-deficient mouse embryonic fibroblasts (MEFs) and primary hepatocytes that had been treated with 2 distinct classes of small-molecule AMPK activators. We identified unique compound-dependent gene expression signatures and several AMPK-regulated genes, including folliculin (Flcn), which encodes the tumor suppressor FLCN. Bioinformatics analysis highlighted the lysosomal pathway and the associated transcription factor EB (TFEB) as a key transcriptional mediator responsible for AMPK responses. AMPK-induced Flcn expression was abolished in MEFs lacking TFEB and transcription factor E3, 2 transcription factors with partially redundant function; additionally, the promoter activity of Flcn was profoundly reduced when its putative TFEB-binding site was mutated. The AMPK-TFEB-FLCN axis is conserved across species; swimming exercise in WT zebrafish induced Flcn expression in muscle, which was significantly reduced in AMPK-deficient zebrafish. Mechanistically, we have found that AMPK promotes dephosphorylation and nuclear localization of TFEB independently of mammalian target of rapamycin activity. Collectively, we identified the novel AMPK-TFEB-FLCN axis, which may function as a key cascade for cellular and metabolic adaptations.—Collodet, C., Foretz, M., Deak, M., Bultot, L., Metairon, S., Viollet, B., Lefebvre, G., Raymond, F., Parisi, A., Civiletto, G., Gut, P., Descombes, P., Sakamoto, K. AMPK promotes induction of the tumor suppressor FLCN through activation of TFEB independently of mTOR.
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Affiliation(s)
- Caterina Collodet
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland.,School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Marc Foretz
- INSERM Unité 1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Maria Deak
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Laurent Bultot
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Sylviane Metairon
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Benoit Viollet
- INSERM Unité 1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Gregory Lefebvre
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Frederic Raymond
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Alice Parisi
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Gabriele Civiletto
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Philipp Gut
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Patrick Descombes
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland.,School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
| | - Kei Sakamoto
- Nestlé Research, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland.,School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, Lausanne, Switzerland
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14
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Zhang X, Yang S, Chen J, Su Z. Unraveling the Regulation of Hepatic Gluconeogenesis. Front Endocrinol (Lausanne) 2019; 9:802. [PMID: 30733709 PMCID: PMC6353800 DOI: 10.3389/fendo.2018.00802] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 12/20/2018] [Indexed: 02/05/2023] Open
Abstract
Hepatic gluconeogenesis, de novo glucose synthesis from available precursors, plays a crucial role in maintaining glucose homeostasis to meet energy demands during prolonged starvation in animals. The abnormally increased rate of hepatic gluconeogenesis contributes to hyperglycemia in diabetes. Gluconeogenesis is regulated on multiple levels, such as hormonal secretion, gene transcription, and posttranslational modification. We review here the molecular mechanisms underlying the transcriptional regulation of gluconeogenesis in response to nutritional and hormonal changes. The nutrient state determines the hormone release, which instigates the signaling cascades in the liver to modulate the activities of various transcriptional factors through various post-translational modifications like phosphorylation, methylation, and acetylation. AMP-activated protein kinase (AMPK) can mediate the activities of some transcription factors, however its role in the regulation of gluconeogenesis remains uncertain. Metformin, a primary hypoglycemic agent of type 2 diabetes, ameliorates hyperglycemia predominantly through suppression of hepatic gluconeogenesis. Several molecular mechanisms have been proposed to be metformin's mode of action.
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Affiliation(s)
| | | | | | - Zhiguang Su
- Molecular Medicine Research Center and National Clinical Research Center for Geriatrics, West China Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, China
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15
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Intracellular signaling of the AMP-activated protein kinase. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 116:171-207. [DOI: 10.1016/bs.apcsb.2018.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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16
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A769662 Inhibits Insulin-Stimulated Akt Activation in Human Macrovascular Endothelial Cells Independent of AMP-Activated Protein Kinase. Int J Mol Sci 2018; 19:ijms19123886. [PMID: 30563079 PMCID: PMC6321332 DOI: 10.3390/ijms19123886] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 12/03/2018] [Indexed: 01/15/2023] Open
Abstract
Protein kinase B (Akt) is a key enzyme in the insulin signalling cascade, required for insulin-stimulated NO production in endothelial cells (ECs). Previous studies have suggested that AMP-activated protein kinase (AMPK) activation stimulates NO synthesis and enhances insulin-stimulated Akt activation, yet these studies have largely used indirect activators of AMPK. The effects of the allosteric AMPK activator A769662 on insulin signalling and endothelial function was therefore examined in cultured human macrovascular ECs. Surprisingly, A769662 inhibited insulin-stimulated NO synthesis and Akt phosphorylation in human ECs from umbilical veins (HUVECs) and aorta (HAECs). In contrast, the AMPK activators compound 991 and AICAR had no substantial inhibitory effect on insulin-stimulated Akt phosphorylation in ECs. Inhibition of AMPK with SBI-0206965 had no effect on the inhibition of insulin-stimulated Akt phosphorylation by A769662, suggesting the inhibitory action of A769662 is AMPK-independent. A769662 decreased IGF1-stimulated Akt phosphorylation yet had no effect on VEGF-stimulated Akt signalling in HUVECs, suggesting that A769662 attenuates early insulin/IGF1 signalling. The effects of A769662 on insulin-stimulated Akt phosphorylation were specific to human ECs, as no effect was observed in the human cancer cell lines HepG2 or HeLa, as well as in mouse embryonic fibroblasts (MEFs). A769662 inhibited insulin-stimulated Erk1/2 phosphorylation in HAECs and MEFs, an effect that was independent of AMPK in MEFs. Therefore, despite being a potent AMPK activator, A769662 has effects unlikely to be mediated by AMPK in human macrovascular ECs that reduce insulin sensitivity and eNOS activation.
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17
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Kodiha M, Flamant E, Wang YM, Stochaj U. Defining the short-term effects of pharmacological 5'-AMP activated kinase modulators on mitochondrial polarization, morphology and heterogeneity. PeerJ 2018; 6:e5469. [PMID: 30186684 PMCID: PMC6119600 DOI: 10.7717/peerj.5469] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 07/27/2018] [Indexed: 01/09/2023] Open
Abstract
Background Under aerobic growth conditions, mitochondria are the major producers of cellular ATP and crucial for the proper performance of organs and tissues. This applies especially to cells with high energy demand, such as the renal proximal tubule epithelium. Mitochondrial dysfunction contributes to the pathology of human health conditions, including various kidney diseases. The improvement of mitochondrial function ameliorates some of these pathologies. This can potentially be achieved with pharmacological compounds. For example, long-term treatment with activators of 5'-AMP activated kinase (AMPK) enhances mitochondrial biogenesis. However, pharmacological damage control during acute cell injury requires that the short-term effects of these compounds and the impact on healthy cells are also understood. It was our objective to define the changes elicited by established modulators of AMPK activity in healthy renal proximal tubule cells. Methods Our work combines confocal microscopy with quantitative image analysis, 3D image reconstruction and Western blotting to provide novel insights into the biology of mitochondria. Specifically, we evaluated the effects of pharmacological AMPK modulators (compound C, AICAR, phenformin, resveratrol) on mitochondrial polarization, morphology and heterogeneity. Microscopic studies generated information at the single cell and subcellular levels. Our research focused on LLC-PK1 cells that are derived from the renal proximal tubule. Mitochondrial heterogeneity was also examined in MCF7 breast cancer cells. Results Pharmacological agents that affect AMPK activity in renal proximal tubule cells can alter mitochondrial organization and the electrochemical potential across the inner mitochondrial membrane. These changes were compound-specific. Short-term incubation with the AMPK inhibitor compound C caused mitochondrial hyperpolarization. This was accompanied by mitochondrial fragmentation. By contrast, AMPK activators AICAR, phenformin and resveratrol had little impact. We further show that the biological properties of mitochondria are determined by their subcellular location. Mitochondria at the cell periphery displayed higher MitoTracker/Tom70 values as compared to organelles located in the vicinity of the nucleus. This was not limited to renal proximal tubule cells, but also observed in MCF7 cells. Pharmacological AMPK modulators altered these location-dependent properties in a compound-specific fashion. While the region-dependent differences were enhanced with phenformin, they were ameliorated by resveratrol. Discussion We evaluated the rapid changes in mitochondrial characteristics that are induced by pharmacological AMPK modulators. Our research supports the concept that pharmacological agents that target AMPK can rearrange mitochondrial networks at the single cell level. Collectively, these insights are relevant to the development of proper strategies for the short-term adjustment of mitochondrial performance.
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Affiliation(s)
- Mohamed Kodiha
- Department of Physiology, McGill University, Montreal, Canada
| | - Etienne Flamant
- Department of Physiology, McGill University, Montreal, Canada
| | - Yi Meng Wang
- Department of Physiology, McGill University, Montreal, Canada
| | - Ursula Stochaj
- Department of Physiology, McGill University, Montreal, Canada
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18
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Olivier S, Foretz M, Viollet B. Promise and challenges for direct small molecule AMPK activators. Biochem Pharmacol 2018; 153:147-158. [PMID: 29408352 DOI: 10.1016/j.bcp.2018.01.049] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 01/31/2018] [Indexed: 12/11/2022]
Abstract
AMP-activated protein kinase (AMPK) is an evolutionary conserved and ubiquitously expressed serine/threonine kinase playing a central role in the coordination of energy homeostasis. Based on the beneficial outcomes of its activation on metabolism, AMPK has emerged as an attractive target for the treatment of metabolic diseases. Identification of novel downstream targets of AMPK beyond the regulation of energy metabolism has renewed considerable attention in exploiting AMPK signaling for novel therapeutic targeting strategies including treatment of cancer and inflammatory diseases. The complexity of AMPK system with tissue- and species-specific expression of multiple isoform combination regulated by various inputs, post-traductional modifications and subcellular locations presents unique challenges for drug discovery. Here, we review the most recent advances in the understanding of the mechanism(s) of action of direct small molecule AMPK activators and the potential therapeutic opportunities.
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Affiliation(s)
- Séverine Olivier
- INSERM, U1016, Institut Cochin, Paris, France; CNRS, UMR8104, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, France
| | - Marc Foretz
- INSERM, U1016, Institut Cochin, Paris, France; CNRS, UMR8104, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, France
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris, France; CNRS, UMR8104, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, France.
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19
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Gélinas R, Mailleux F, Dontaine J, Bultot L, Demeulder B, Ginion A, Daskalopoulos EP, Esfahani H, Dubois-Deruy E, Lauzier B, Gauthier C, Olson AK, Bouchard B, Des Rosiers C, Viollet B, Sakamoto K, Balligand JL, Vanoverschelde JL, Beauloye C, Horman S, Bertrand L. AMPK activation counteracts cardiac hypertrophy by reducing O-GlcNAcylation. Nat Commun 2018; 9:374. [PMID: 29371602 PMCID: PMC5785516 DOI: 10.1038/s41467-017-02795-4] [Citation(s) in RCA: 171] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 12/28/2017] [Indexed: 12/11/2022] Open
Abstract
AMP-activated protein kinase (AMPK) has been shown to inhibit cardiac hypertrophy. Here, we show that submaximal AMPK activation blocks cardiomyocyte hypertrophy without affecting downstream targets previously suggested to be involved, such as p70 ribosomal S6 protein kinase, calcineurin/nuclear factor of activated T cells (NFAT) and extracellular signal-regulated kinases. Instead, cardiomyocyte hypertrophy is accompanied by increased protein O-GlcNAcylation, which is reversed by AMPK activation. Decreasing O-GlcNAcylation by inhibitors of the glutamine:fructose-6-phosphate aminotransferase (GFAT), blocks cardiomyocyte hypertrophy, mimicking AMPK activation. Conversely, O-GlcNAcylation-inducing agents counteract the anti-hypertrophic effect of AMPK. In vivo, AMPK activation prevents myocardial hypertrophy and the concomitant rise of O-GlcNAcylation in wild-type but not in AMPKα2-deficient mice. Treatment of wild-type mice with O-GlcNAcylation-inducing agents reverses AMPK action. Finally, we demonstrate that AMPK inhibits O-GlcNAcylation by mainly controlling GFAT phosphorylation, thereby reducing O-GlcNAcylation of proteins such as troponin T. We conclude that AMPK activation prevents cardiac hypertrophy predominantly by inhibiting O-GlcNAcylation.
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Affiliation(s)
- Roselle Gélinas
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Florence Mailleux
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Justine Dontaine
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Laurent Bultot
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Bénédicte Demeulder
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Audrey Ginion
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Evangelos P Daskalopoulos
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Hrag Esfahani
- Pole of Pharmacotherapy, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Emilie Dubois-Deruy
- Pole of Pharmacotherapy, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Benjamin Lauzier
- l'institut du thorax, INSERM, CNRS, Univ. Nantes, Nantes, 44007, France
| | - Chantal Gauthier
- l'institut du thorax, INSERM, CNRS, Univ. Nantes, Nantes, 44007, France
| | - Aaron K Olson
- Department of Pediatrics, University of Washington School of Medicine and Seattle Children's Research Institute, Seattle, 98105-0371, WA, USA.,Montreal Heart Institute, Montreal, H1T 1C8, Canada
| | | | - Christine Des Rosiers
- Montreal Heart Institute, Montreal, H1T 1C8, Canada.,Department of Nutrition, Université de Montréal, Montreal, H3T 1A8, Canada
| | - Benoit Viollet
- Institut Cochin, INSERM U1016, 75014, Paris, France.,CNRS UMR8104, 75014, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, 75014, France
| | - Kei Sakamoto
- Nestlé Institute of Health Sciences SA, Lausanne, 1015, Switzerland
| | - Jean-Luc Balligand
- Pole of Pharmacotherapy, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Jean-Louis Vanoverschelde
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium.,Division of Cardiology, Cliniques Universitaires Saint-Luc, Brussels, 1200, Belgium
| | - Christophe Beauloye
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium.,Division of Cardiology, Cliniques Universitaires Saint-Luc, Brussels, 1200, Belgium
| | - Sandrine Horman
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Luc Bertrand
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, 1200, Belgium.
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Dial AG, Rooprai P, Lally JS, Bujak AL, Steinberg GR, Ljubicic V. The role of AMP‐activated protein kinase in the expression of the dystrophin‐associated protein complex in skeletal muscle. FASEB J 2018; 32:2950-2965. [DOI: 10.1096/fj.201700868rrr] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Athan G. Dial
- Department of KinesiologyMcMaster University Hamilton Ontario Canada
| | - Paul Rooprai
- Department of KinesiologyMcMaster University Hamilton Ontario Canada
| | - James S. Lally
- Department of MedicineMcMaster University Hamilton Ontario Canada
| | - Adam L. Bujak
- Department of MedicineMcMaster University Hamilton Ontario Canada
| | - Gregory R. Steinberg
- Department of MedicineMcMaster University Hamilton Ontario Canada
- Department of Biochemistry and Biomedical SciencesMcMaster University Hamilton Ontario Canada
| | - Vladimir Ljubicic
- Department of KinesiologyMcMaster University Hamilton Ontario Canada
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21
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Boudaba N, Marion A, Huet C, Pierre R, Viollet B, Foretz M. AMPK Re-Activation Suppresses Hepatic Steatosis but its Downregulation Does Not Promote Fatty Liver Development. EBioMedicine 2018; 28:194-209. [PMID: 29343420 PMCID: PMC5835560 DOI: 10.1016/j.ebiom.2018.01.008] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/05/2018] [Accepted: 01/05/2018] [Indexed: 12/12/2022] Open
Abstract
Nonalcoholic fatty liver disease is a highly prevalent component of disorders associated with disrupted energy homeostasis. Although dysregulation of the energy sensor AMP-activated protein kinase (AMPK) is viewed as a pathogenic factor in the development of fatty liver its role has not been directly demonstrated. Unexpectedly, we show here that liver-specific AMPK KO mice display normal hepatic lipid homeostasis and are not prone to fatty liver development, indicating that the decreases in AMPK activity associated with hepatic steatosis may be a consequence, rather than a cause, of changes in hepatic metabolism. In contrast, we found that pharmacological re-activation of downregulated AMPK in fatty liver is sufficient to normalize hepatic lipid content. Mechanistically, AMPK activation reduces hepatic triglyceride content both by inhibiting lipid synthesis and by stimulating fatty acid oxidation in an LKB1-dependent manner, through a transcription-independent mechanism. Furthermore, the effect of the antidiabetic drug metformin on lipogenesis inhibition and fatty acid oxidation stimulation was enhanced by combination treatment with small-molecule AMPK activators in primary hepatocytes from mice and humans. Overall, these results demonstrate that AMPK downregulation is not a triggering factor in fatty liver development but in contrast, establish the therapeutic impact of pharmacological AMPK re-activation in the treatment of fatty liver disease. Hepatic AMPK deficiency is not sufficient to trigger fatty liver development Re-activation of downregulated AMPK in fatty liver normalizes hepatic lipid content Hepatic AMPK activation both inhibits lipogenesis and stimulates fatty acid oxidation AMPK activation modulates lipid metabolism via a transcription-independent mechanism Small-molecule AMPK activators enhance metformin effects on hepatic lipid metabolism
Nonalcoholic fatty liver disease is a highly prevalent component of metabolic syndrome, for which treatment options are limited. Downregulation of the energy sensor AMPK is viewed as a pathogenic factor in the development of fatty liver. However, we show here hepatic AMPK suppression is not sufficient to promote hepatic lipid accumulation, indicating that the decreases in AMPK activity associated with hepatic steatosis may be a consequence, rather than a cause, of changes in hepatic metabolism. In contrast, we found that pharmacological re-activation of downregulated AMPK in fatty liver is sufficient to normalize hepatic lipid content. Thus, these results establish the therapeutic impact of pharmacological AMPK re-activation in the treatment of fatty liver disease.
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Affiliation(s)
- Nadia Boudaba
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France
| | - Allison Marion
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France
| | - Camille Huet
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France
| | - Rémi Pierre
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France
| | - Marc Foretz
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France.
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22
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Feng Y, Zhang Y, Xiao H. AMPK and cardiac remodelling. SCIENCE CHINA-LIFE SCIENCES 2017; 61:14-23. [PMID: 29170891 DOI: 10.1007/s11427-017-9197-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 08/11/2017] [Indexed: 12/17/2022]
Abstract
Cardiac remodelling is generally accepted as a critical process in the progression of heart failure. Myocyte hypertrophy, inflammatory responses and cardiac fibrosis are the main pathological changes associated with cardiac remodelling. AMP-activated protein kinase (AMPK) is known as an energy sensor and a regulator of cardiac metabolism under normal and ischaemic conditions. Additionally, AMPK has been shown to play roles in cardiac remodelling extending well beyond metabolic regulation. In this review, we discuss the currently defined roles of AMPK in cardiac remodelling and summarize the effects of AMPK on cardiac hypertrophy, inflammatory responses and fibrosis and the molecular mechanisms underlying these effects. In addition, we discuss some pharmacological activators of AMPK that are promising treatments for cardiac remodelling.
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Affiliation(s)
- Yenan Feng
- Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing, 100191, China
| | - Youyi Zhang
- Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing, 100191, China
| | - Han Xiao
- Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing, 100191, China.
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23
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Woods A, Williams JR, Muckett PJ, Mayer FV, Liljevald M, Bohlooly-Y M, Carling D. Liver-Specific Activation of AMPK Prevents Steatosis on a High-Fructose Diet. Cell Rep 2017; 18:3043-3051. [PMID: 28355557 PMCID: PMC5382239 DOI: 10.1016/j.celrep.2017.03.011] [Citation(s) in RCA: 147] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 02/02/2017] [Accepted: 03/01/2017] [Indexed: 12/14/2022] Open
Abstract
AMP-activated protein kinase (AMPK) plays a key role in integrating metabolic pathways in response to energy demand. We identified a mutation in the γ1 subunit (γ1D316A) that leads to activation of AMPK. We generated mice with this mutation to study the effect of chronic liver-specific activation of AMPK in vivo. Primary hepatocytes isolated from these mice have reduced gluconeogenesis and fatty acid synthesis, but there is no effect on fatty acid oxidation compared to cells from wild-type mice. Liver-specific activation of AMPK decreases lipogenesis in vivo and completely protects against hepatic steatosis when mice are fed a high-fructose diet. Our findings demonstrate that liver-specific activation of AMPK is sufficient to protect against hepatic triglyceride accumulation, a hallmark of non-alcoholic fatty liver disease (NAFLD). These results emphasize the clinical relevance of activating AMPK in the liver to combat NAFLD and potentially other associated complications (e.g., cirrhosis and hepatocellular carcinoma).
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Affiliation(s)
- Angela Woods
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK.
| | - Jennet R Williams
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Phillip J Muckett
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Faith V Mayer
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Maria Liljevald
- Drug Safety and Metabolism, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Pepparedsleden 1, Mölndal 431 83, Sweden
| | - Mohammad Bohlooly-Y
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Pepparedsleden 1, Mölndal 431 83, Sweden
| | - David Carling
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK; Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital, London W12 0NN, UK.
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24
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A Novel Phenylchromane Derivative Increases the Rate of Glucose Uptake in L6 Myotubes and Augments Insulin Secretion from Pancreatic Beta-Cells by Activating AMPK. Pharm Res 2017; 34:2873-2890. [DOI: 10.1007/s11095-017-2271-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 09/24/2017] [Indexed: 01/04/2023]
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25
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Guigas B, Viollet B. Targeting AMPK: From Ancient Drugs to New Small-Molecule Activators. ACTA ACUST UNITED AC 2017; 107:327-350. [PMID: 27812986 DOI: 10.1007/978-3-319-43589-3_13] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The AMP-activated protein kinase (AMPK) is an evolutionary conserved and ubiquitously expressed serine/threonine kinase mainly acting as a key regulator of cellular energy homeostasis. AMPK is a heterotrimeric protein complex, consisting of a catalytic α subunit and two regulatory β and γ subunits, whose activity is tightly regulated by changes in adenine nucleotides and several posttranslational modifications. Once activated in response to energy deficit, AMPK concomitantly inhibits ATP-consuming anabolic processes and promotes ATP-generating catabolic pathways via direct phosphorylation of multiple downstream effectors, leading to restoration of cellular energy balance. A growing number of energy/nutrient-independent functions of AMPK are also regularly reported, progressively expanding its role to regulation of non-metabolic cellular processes. Historically, AMPK as a therapeutic target has attracted much of interest due to its potential impact on metabolic disorders, such as obesity and type 2 diabetes, but has also recently received considerable renewed attention in the framework of cancer studies, highlighting the persistent need for selective, reversible, potent, and tissue-specific activators. In this chapter, we review the most recent advances in the understanding of the mechanism(s) of action of the current portfolio of AMPK activators, including plant-derived natural compounds and newly discovered small-molecule agonists directly targeting various AMPK subunits.
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Affiliation(s)
- Bruno Guigas
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands.
- Department of Parasitology, Leiden University Medical Center, 9600, Postzone L40-Q, 2300 RC, Leiden, The Netherlands.
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, France
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26
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Chen L, Chen Q, Rong P, Wang HY, Chen S. The energy sensing LKB1-AMPKα1 pathway regulates IGF1 secretion and consequent activation of the IGF1R-PKB pathway in primary hepatocytes. FEBS J 2017; 284:2096-2109. [PMID: 28500773 DOI: 10.1111/febs.14106] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 05/05/2017] [Accepted: 05/10/2017] [Indexed: 12/22/2022]
Abstract
The insulin-like growth factor 1 (IGF1) pathway has been linked with various diseases including diabetes, cancer and aging. In contrast to the well-established regulatory mechanisms controlling IGF1 expression, molecular mechanisms regulating its secretion are not fully understood. The AMP-activated protein kinase (AMPK) is a key energy sensor, and cumulative evidence shows that it is an attractive therapeutic target for treatment of diabetes, cancer and aging. Here we found that deficiency of AMPK promoted IGF1 secretion in mouse primary hepatocytes. Furthermore, we found that AMPKα1 but not AMPKα2 was involved in regulation of IGF1 secretion in mouse primary hepatocytes. Knockout of AMPK caused activation of the IGF1 receptor (IGF1R)-protein kinase B (PKB; also known as Akt) pathway in hepatocytes, which was mediated by hypersecretion of IGF1. Upstream of AMPK, liver kinase B1 (LKB1) was responsible for AMPK-dependent suppression of IGF1 secretion in hepatocytes. Collectively, these findings demonstrate that the energy-sensing LKB1-AMPK pathway regulates IGF1 secretion in mouse primary hepatocytes, which in turn regulates activation of the IGF1R-PKB pathway.
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Affiliation(s)
- Liang Chen
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, China
| | - Qiaoli Chen
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, China
| | - Ping Rong
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, China
| | - Hong Yu Wang
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, China
| | - Shuai Chen
- MOE Key Laboratory of Model Animal for Disease Study and State Key Laboratory of Pharmaceutical Biotechnology, Model Animal Research Center, Nanjing University, China
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27
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Mancini SJ, White AD, Bijland S, Rutherford C, Graham D, Richter EA, Viollet B, Touyz RM, Palmer TM, Salt IP. Activation of AMP-activated protein kinase rapidly suppresses multiple pro-inflammatory pathways in adipocytes including IL-1 receptor-associated kinase-4 phosphorylation. Mol Cell Endocrinol 2017; 440:44-56. [PMID: 27840174 PMCID: PMC5228585 DOI: 10.1016/j.mce.2016.11.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 11/08/2016] [Accepted: 11/10/2016] [Indexed: 12/29/2022]
Abstract
Inflammation of adipose tissue in obesity is associated with increased IL-1β, IL-6 and TNF-α secretion and proposed to contribute to insulin resistance. AMP-activated protein kinase (AMPK) regulates nutrient metabolism and is reported to have anti-inflammatory actions in adipose tissue, yet the mechanisms underlying this remain poorly characterised. The effect of AMPK activation on cytokine-stimulated proinflammatory signalling was therefore assessed in cultured adipocytes. AMPK activation inhibited IL-1β-stimulated CXCL10 secretion, associated with reduced interleukin-1 receptor associated kinase-4 (IRAK4) phosphorylation and downregulated MKK4/JNK and IKK/IκB/NFκB signalling. AMPK activation inhibited TNF-α-stimulated IKK/IκB/NFκB signalling but had no effect on JNK phosphorylation. The JAK/STAT3 pathway was also suppressed by AMPK after IL-6 stimulation and during adipogenesis. Adipose tissue from AMPKα1-/- mice exhibited increased JNK and STAT3 phosphorylation, supporting suppression of these distinct proinflammatory pathways by AMPK in vivo. The inhibition of multiple pro-inflammatory signalling pathways by AMPK may underlie the reported beneficial effects of AMPK activation in adipose tissue.
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Affiliation(s)
- Sarah J Mancini
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Anna D White
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Silvia Bijland
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Claire Rutherford
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Delyth Graham
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Erik A Richter
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris, France; CNRS, UMR8104, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, France
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Timothy M Palmer
- School of Pharmacy, University of Bradford, Bradford, West Yorkshire, BD7 1DP, United Kingdom
| | - Ian P Salt
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
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Pirkmajer S, Chibalin AV. Na,K-ATPase regulation in skeletal muscle. Am J Physiol Endocrinol Metab 2016; 311:E1-E31. [PMID: 27166285 DOI: 10.1152/ajpendo.00539.2015] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 05/02/2016] [Indexed: 12/17/2022]
Abstract
Skeletal muscle contains one of the largest and the most dynamic pools of Na,K-ATPase (NKA) in the body. Under resting conditions, NKA in skeletal muscle operates at only a fraction of maximal pumping capacity, but it can be markedly activated when demands for ion transport increase, such as during exercise or following food intake. Given the size, capacity, and dynamic range of the NKA pool in skeletal muscle, its tight regulation is essential to maintain whole body homeostasis as well as muscle function. To reconcile functional needs of systemic homeostasis with those of skeletal muscle, NKA is regulated in a coordinated manner by extrinsic stimuli, such as hormones and nerve-derived factors, as well as by local stimuli arising in skeletal muscle fibers, such as contractions and muscle energy status. These stimuli regulate NKA acutely by controlling its enzymatic activity and/or its distribution between the plasma membrane and the intracellular storage compartment. They also regulate NKA chronically by controlling NKA gene expression, thus determining total NKA content in skeletal muscle and its maximal pumping capacity. This review focuses on molecular mechanisms that underlie regulation of NKA in skeletal muscle by major extrinsic and local stimuli. Special emphasis is given to stimuli and mechanisms linking regulation of NKA and energy metabolism in skeletal muscle, such as insulin and the energy-sensing AMP-activated protein kinase. Finally, the recently uncovered roles for glutathionylation, nitric oxide, and extracellular K(+) in the regulation of NKA in skeletal muscle are highlighted.
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Affiliation(s)
- Sergej Pirkmajer
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia; and
| | - Alexander V Chibalin
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
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29
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Kim J, Yang G, Kim Y, Kim J, Ha J. AMPK activators: mechanisms of action and physiological activities. Exp Mol Med 2016; 48:e224. [PMID: 27034026 PMCID: PMC4855276 DOI: 10.1038/emm.2016.16] [Citation(s) in RCA: 472] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 12/28/2015] [Accepted: 12/29/2015] [Indexed: 02/07/2023] Open
Abstract
AMP-activated protein kinase (AMPK) is a central regulator of energy homeostasis, which coordinates metabolic pathways and thus balances nutrient supply with energy demand. Because of the favorable physiological outcomes of AMPK activation on metabolism, AMPK has been considered to be an important therapeutic target for controlling human diseases including metabolic syndrome and cancer. Thus, activators of AMPK may have potential as novel therapeutics for these diseases. In this review, we provide a comprehensive summary of both indirect and direct AMPK activators and their modes of action in relation to the structure of AMPK. We discuss the functional differences among isoform-specific AMPK complexes and their significance regarding the development of novel AMPK activators and the potential for combining different AMPK activators in the treatment of human disease.
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Affiliation(s)
- Joungmok Kim
- Depatment of Oral Biochemistry and Molecular Biology, School of Dentistry, Kyung Hee University, Seoul, Korea
| | - Goowon Yang
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Korea
| | - Yeji Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Korea
| | - Jin Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Korea
| | - Joohun Ha
- Department of Biochemistry and Molecular Biology, Graduate School, Kyung Hee University, Seoul, Korea
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30
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Ido Y. Diabetic complications within the context of aging: Nicotinamide adenine dinucleotide redox, insulin C-peptide, sirtuin 1-liver kinase B1-adenosine monophosphate-activated protein kinase positive feedback and forkhead box O3. J Diabetes Investig 2016; 7:448-58. [PMID: 27181414 PMCID: PMC4931191 DOI: 10.1111/jdi.12485] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 01/17/2016] [Accepted: 01/18/2016] [Indexed: 12/31/2022] Open
Abstract
Recent research in nutritional control of aging suggests that cytosolic increases in the reduced form of nicotinamide adenine dinucleotide and decreasing nicotinamide adenine dinucleotide metabolism plays a central role in controlling the longevity gene products sirtuin 1 (SIRT1), adenosine monophosphate‐activated protein kinase (AMPK) and forkhead box O3 (FOXO3). High nutrition conditions, such as the diabetic milieu, increase the ratio of reduced to oxidized forms of cytosolic nicotinamide adenine dinucleotide through cascades including the polyol pathway. This redox change is associated with insulin resistance and the development of diabetic complications, and might be counteracted by insulin C‐peptide. My research and others' suggest that the SIRT1–liver kinase B1–AMPK cascade creates positive feedback through nicotinamide adenine dinucleotide synthesis to help cells cope with metabolic stress. SIRT1 and AMPK can upregulate liver kinase B1 and FOXO3, key factors that help residential stem cells cope with oxidative stress. FOXO3 directly changes epigenetics around transcription start sites, maintaining the health of stem cells. ‘Diabetic memory’ is likely a result of epigenetic changes caused by high nutritional conditions, which disturb the quiescent state of residential stem cells and impair tissue repair. This could be prevented by restoring SIRT1–AMPK positive feedback through activating FOXO3.
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Affiliation(s)
- Yasuo Ido
- Boston University School of Medicine, Boston, Massachusetts, USA
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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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Guma M, Wang Y, Viollet B, Liu-Bryan R. AMPK Activation by A-769662 Controls IL-6 Expression in Inflammatory Arthritis. PLoS One 2015; 10:e0140452. [PMID: 26474486 PMCID: PMC4608670 DOI: 10.1371/journal.pone.0140452] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 09/25/2015] [Indexed: 01/11/2023] Open
Abstract
Objective AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase critically involved in the regulation of cellular energy homeostasis. It is a central regulator of both lipid and glucose metabolism. Many studies have suggested that AMPK activation exert significant anti-inflammatory and immunosuppressive effects. In this study, we assessed whether targeted activation of AMPK inhibits inflammatory arthritis in vivo. Methods We tested the effect of A-769662, a specific AMPK agonist (60mg/kg/bid) in mouse models of antigen-induced arthritis (AIA) and passive K/BxN serum-induced arthritis. The passive K/BxN serum-induced arthritis model was also applied to AMPKα1-deficient mice. Joints were harvested and subjected to histological analysis. IL-6 expression was measured in both joint tissues and sera by ELISA. The effect of A-769662 on bone marrow derived macrophage (BMDM) response to stimulation with TLR2 and TLR4 agonists was tested in vitro. Results AMPK activation by A-769662 reduced inflammatory infiltration and joint damage in both mouse models. IL-6 expression in serum and arthritic joints was significantly decreased in A-769662-treated mice. AMPKα1 deficient mice mildly elicited an increase of clinical arthritis. IL-6 expression at both mRNA and protein levels, phosphorylation of p65 NF-κB and MAPK phosphorylation were inhibited by A-769662 in BMDMs stimulated with either TLR2 or TLR4 agonists. Conclusions AMPK activation by specific AMPK agonist A-769662 suppressed inflammatory arthritis in mice as well as IL-6 expression in serum and arthritic joints. These data suggest that targeted activation of AMPK has a potential to be an effective therapeutic strategy for IL-6 dependent inflammatory arthritis.
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Affiliation(s)
- Monica Guma
- Division of Rheumatology, Allergy and Immunology, UC San Diego School of Medicine, La Jolla, California, United States of America
- * E-mail: (MG); (RLB)
| | - Yun Wang
- Division of Rheumatology, Allergy and Immunology, UC San Diego School of Medicine, La Jolla, California, United States of America
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Ru Liu-Bryan
- Division of Rheumatology, Allergy and Immunology, UC San Diego School of Medicine, La Jolla, California, United States of America
- VA San Diego Healthcare System, 3350 La Jolla Village Drive, La Jolla, California, United States of America
- * E-mail: (MG); (RLB)
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Skeffington KL, Higgins JS, Mahmoud AD, Evans AM, Sferruzzi-Perri AN, Fowden AL, Yung HW, Burton GJ, Giussani DA, Moore LG. Hypoxia, AMPK activation and uterine artery vasoreactivity. J Physiol 2015; 594:1357-69. [PMID: 26110512 DOI: 10.1113/jp270995] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 06/21/2015] [Indexed: 01/12/2023] Open
Abstract
Genes near adenosine monophosphate-activated protein kinase-α1 (PRKAA1) have been implicated in the greater uterine artery (UtA) blood flow and relative protection from fetal growth restriction seen in altitude-adapted Andean populations. Adenosine monophosphate-activated protein kinase (AMPK) activation vasodilates multiple vessels but whether AMPK is present in UtA or placental tissue and influences UtA vasoreactivity during normal or hypoxic pregnancy remains unknown. We studied isolated UtA and placenta from near-term C57BL/6J mice housed in normoxia (n = 8) or hypoxia (10% oxygen, n = 7-9) from day 14 to day 19, and placentas from non-labouring sea level (n = 3) or 3100 m (n = 3) women. Hypoxia increased AMPK immunostaining in near-term murine UtA and placental tissue. RT-PCR products for AMPK-α1 and -α2 isoforms and liver kinase B1 (LKB1; the upstream kinase activating AMPK) were present in murine and human placenta, and hypoxia increased LKB1 and AMPK-α1 and -α2 expression in the high- compared with low-altitude human placentas. Pharmacological AMPK activation by A769662 caused phenylephrine pre-constricted UtA from normoxic or hypoxic pregnant mice to dilate and this dilatation was partially reversed by the NOS inhibitor l-NAME. Hypoxic pregnancy sufficient to restrict fetal growth markedly augmented the UtA vasodilator effect of AMPK activation in opposition to PE constriction as the result of both NO-dependent and NO-independent mechanisms. We conclude that AMPK is activated during hypoxic pregnancy and that AMPK activation vasodilates the UtA, especially in hypoxic pregnancy. AMPK activation may be playing an adaptive role by limiting cellular energy depletion and helping to maintain utero-placental blood flow in hypoxic pregnancy.
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Affiliation(s)
- K L Skeffington
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - J S Higgins
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - A D Mahmoud
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
| | - A M Evans
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
| | - A N Sferruzzi-Perri
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - A L Fowden
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - H W Yung
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - G J Burton
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - D A Giussani
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - L G Moore
- Division of Basic Reproductive Sciences, Department of Obstetrics & Gynaecology, University of Colorado Denver, Aurora, CO, USA
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Ross E, Ata R, Thavarajah T, Medvedev S, Bowden P, Marshall JG, Antonescu CN. AMP-Activated Protein Kinase Regulates the Cell Surface Proteome and Integrin Membrane Traffic. PLoS One 2015; 10:e0128013. [PMID: 26010094 PMCID: PMC4444004 DOI: 10.1371/journal.pone.0128013] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 04/21/2015] [Indexed: 12/11/2022] Open
Abstract
The cell surface proteome controls numerous cellular functions including cell migration and adhesion, intercellular communication and nutrient uptake. Cell surface proteins are controlled by acute changes in protein abundance at the plasma membrane through regulation of endocytosis and recycling (endomembrane traffic). Many cellular signals regulate endomembrane traffic, including metabolic signaling; however, the extent to which the cell surface proteome is controlled by acute regulation of endomembrane traffic under various conditions remains incompletely understood. AMP-activated protein kinase (AMPK) is a key metabolic sensor that is activated upon reduced cellular energy availability. AMPK activation alters the endomembrane traffic of a few specific proteins, as part of an adaptive response to increase energy intake and reduce energy expenditure. How increased AMPK activity during energy stress may globally regulate the cell surface proteome is not well understood. To study how AMPK may regulate the cell surface proteome, we used cell-impermeable biotinylation to selectively purify cell surface proteins under various conditions. Using ESI-MS/MS, we found that acute (90 min) treatment with the AMPK activator A-769662 elicits broad control of the cell surface abundance of diverse proteins. In particular, A-769662 treatment depleted from the cell surface proteins with functions in cell migration and adhesion. To complement our mass spectrometry results, we used other methods to show that A-769662 treatment results in impaired cell migration. Further, A-769662 treatment reduced the cell surface abundance of β1-integrin, a key cell migration protein, and AMPK gene silencing prevented this effect. While the control of the cell surface abundance of various proteins by A-769662 treatment was broad, it was also selective, as this treatment did not change the cell surface abundance of the transferrin receptor. Hence, the cell surface proteome is subject to acute regulation by treatment with A-769662, at least some of which is mediated by the metabolic sensor AMPK.
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Affiliation(s)
- Eden Ross
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
| | - Rehman Ata
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
| | - Thanusi Thavarajah
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
| | - Sergei Medvedev
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
| | - Peter Bowden
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
| | - John G Marshall
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
| | - Costin N Antonescu
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada
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Hou N, Armstrong GAB, Chakraborty-Chatterjee M, Sokolowski MB, Robertson RM. Na+-K+-ATPase trafficking induced by heat shock pretreatment correlates with increased resistance to anoxia in locusts. J Neurophysiol 2014; 112:814-23. [PMID: 24848469 PMCID: PMC4122745 DOI: 10.1152/jn.00201.2014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 05/17/2014] [Indexed: 01/02/2023] Open
Abstract
The sensitivity of insect nervous systems to anoxia can be modulated genetically and pharmacologically, but the cellular mechanisms responsible are poorly understood. We examined the effect of a heat shock pretreatment (HS) on the sensitivity of the locust (Locusta migratoria) nervous system to anoxia induced by water immersion. Prior HS made locusts more resistant to anoxia by increasing the time taken to enter a coma and by reducing the time taken to recover the ability to stand. Anoxic comas were accompanied by surges of extracellular potassium ions in the neuropile of the metathoracic ganglion, and HS reduced the time taken for clearance of excess extracellular potassium ions. This could not be attributed to a decrease in the activity of protein kinase G, which was increased by HS. In homogenates of the metathoracic ganglion, HS had only a mild effect on the activity of Na(+)-K(+)-ATPase. However, we demonstrated that HS caused a threefold increase in the immunofluorescent localization of the α-subunit of Na(+)-K(+)-ATPase in metathoracic neuronal plasma membranes relative to background labeling of the nucleus. We conclude that HS induced trafficking of Na(+)-K(+)-ATPase into neuronal plasma membranes and suggest that this was at least partially responsible for the increased resistance to anoxia and the increased rate of recovery of neural function after a disturbance of K(+) homeostasis.
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Affiliation(s)
- Nicholas Hou
- Department of Biology, Queen's University, Kingston, Ontario, Canada; and
| | - Gary A B Armstrong
- Department of Biology, Queen's University, Kingston, Ontario, Canada; and
| | | | - Marla B Sokolowski
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
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Pan JSC, Huang L, Belousova T, Lu L, Yang Y, Reddel R, Chang A, Ju H, DiMattia G, Tong Q, Sheikh-Hamad D. Stanniocalcin-1 inhibits renal ischemia/reperfusion injury via an AMP-activated protein kinase-dependent pathway. J Am Soc Nephrol 2014; 26:364-78. [PMID: 25012175 DOI: 10.1681/asn.2013070703] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
AKI is associated with increased morbidity, mortality, and cost of care, and therapeutic options remain limited. Reactive oxygen species are critical for the genesis of ischemic AKI. Stanniocalcin-1 (STC1) suppresses superoxide generation through induction of uncoupling proteins (UCPs), and transgenic overexpression of STC1 inhibits reactive oxygen species and protects from ischemia/reperfusion (I/R) kidney injury. Our observations revealed high AMP-activated protein kinase (AMPK) activity in STC1 transgenic kidneys relative to wild-type (WT) kidneys; thus, we hypothesized that STC1 protects from I/R kidney injury through activation of AMPK. Baseline activity of AMPK in the kidney correlated with the expression of STCs, such that the highest activity was observed in STC1 transgenic mice followed (in decreasing order) by WT, STC1 knockout, and STC1/STC2 double-knockout mice. I/R in WT kidneys increased AMPK activity and the expression of STC1, UCP2, and sirtuin 3. Inhibition of AMPK by administration of compound C before I/R abolished the activation of AMPK, diminished the expression of UCP2 and sirtuin 3, and aggravated kidney injury but did not affect STC1 expression. Treatment of cultured HEK cells with recombinant STC1 activated AMPK and increased the expression of UCP2 and sirtuin 3, and concomitant treatment with compound C abolished these responses. STC1 knockout mice displayed high susceptibility to I/R, whereas pretreatment of STC1 transgenic mice with compound C restored the susceptibility to I/R kidney injury. These data suggest that STC1 is important for activation of AMPK in the kidney, which mediates STC1-induced expression of UCP2 and sirtuin 3 and protection from I/R.
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Affiliation(s)
| | - Luping Huang
- Division of Nephrology, Department of Medicine and
| | | | - Lianghao Lu
- Division of Nephrology, Department of Medicine and
| | - Yongjie Yang
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, Texas
| | - Roger Reddel
- Cancer Research Unit, Children's Medical Research Institute, University of Sydney, Sydney, Australia; and
| | - Andy Chang
- Cancer Research Unit, Children's Medical Research Institute, University of Sydney, Sydney, Australia; and
| | - Huiming Ju
- Division of Nephrology, Department of Medicine and
| | - Gabriel DiMattia
- University of Western Ontario, Departments of Oncology and Biochemistry, London Regional Cancer Center, London, Ontario, Canada
| | - Qiang Tong
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, Texas
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Goodman M, Liu Z, Zhu P, Li J. AMPK Activators as a Drug for Diabetes, Cancer and Cardiovascular Disease. PHARMACEUTICAL REGULATORY AFFAIRS : OPEN ACCESS 2014; 3:118. [PMID: 27478687 PMCID: PMC4966671 DOI: 10.4172/2167-7689.1000118] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The cellular mechanisms of AMP-Activated Protein Kinase (AMPK) activators in the treatment and prevention of diabetes, cancer, and cardiovascular disease.
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Affiliation(s)
- Mark Goodman
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - Zhenling Liu
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
- Department of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Ping Zhu
- Department of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Ji Li
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
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Fraser SA, Davies M, Katerelos M, Gleich K, Choy SW, Steel R, Galic S, Mount PF, Kemp BE, Power DA. Activation of AMPK reduces the co-transporter activity of NKCC1. Mol Membr Biol 2014; 31:95-102. [PMID: 24702155 DOI: 10.3109/09687688.2014.902128] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The co-transporter activity of Na(+)-K(+)-2Cl(-) 1 (NKCC1) is dependent on phosphorylation. In this study we show the energy-sensing kinase AMPK inhibits NKCC1 activity. Three separate AMPK activators (AICAR, Phenformin and A-769662) inhibited NKCC1 flux in a variety of nucleated cells. Treatment with A-769662 resulted in a reduction of NKCC1(T212/T217) phosphorylation, and this was reversed by treatment with the non-selective AMPK inhibitor Compound C. AMPK dependence was confirmed by treatment of AMPK null mouse embryonic fibroblasts, where A-769662 had no effect on NKCC1 mediated transport. AMPK was found to directly phosphorylate a recombinant human-NKCC1 N-terminal fragment (1-293) with the phosphorylated site identified as S77. Mutation of Serine 77 to Alanine partially prevented the inhibitory effect of A-769662 on NKCC1 activity. In conclusion, AMPK can act to reduce NKCC1-mediated transport. While the exact mechanism is still unclear there is evidence for both a direct effect on phosphorylation of S77 and reduced phosphorylation of T212/217.
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Affiliation(s)
- Scott A Fraser
- Institute for Breathing and Sleep, Kidney Laboratory , Melbourne, Australia
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de Castro Barbosa T, Jiang LQ, Zierath JR, Nunes MT. L-Arginine enhances glucose and lipid metabolism in rat L6 myotubes via the NO/ c-GMP pathway. Metabolism 2013; 62:79-89. [PMID: 22889511 DOI: 10.1016/j.metabol.2012.06.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 06/27/2012] [Accepted: 06/27/2012] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The amino acid Arginine (Arg) is the main biological precursor of nitric oxide (NO) and has been described to improve insulin sensitivity in diabetes and obesity. We investigated the molecular mechanisms involved in the long-term effects of Arg on glucose and lipid metabolism. MATERIALS AND METHODS L6 myotubes were treated with Arg (7 mmol/L) for 6 days. D-Mannitol (7 mmol/L) was used as control; spermine NONOate (10 μmol/L) and L-NAME (100 μmol/L) were used to evaluate the NO/c-GMP pathway role. Basal and insulin-induced (120 nmol/L) glycogen synthesis, glucose uptake and lipid oxidation, c-GMP and nitrite levels, and the intracellular signaling pathways were evaluated. RESULTS Arg-treatment increased: 1) basal and insulin-stimulated glycogen synthesis; 2) glucose uptake; 3) palmitate oxidation; 4) p-Akt (Ser(473)), total and plasma membrane GLUT4 content, total and p-AMPK-α and p-ACC (Ser(79)), p-GSK-3α/β (Ser(21/9)) and 5) nitrite and c-GMP levels. L-NAME treatment suppressed Arg effects on: 1) nitrite and c-GMP content; 2) glycogen synthesis and glucose uptake; 3) basal and insulin-stimulated p-Akt (Ser(473)), total and p-AMPK-α and ACC, and nNOS expression. CONCLUSION We provide evidence that Arg improves glucose and lipid metabolism in skeletal muscle, in parallel with increased phosphorylation of Akt and AMPK-α. These effects were mediated by the NO/c-GMP pathway. Thus, arginine treatment enhances signal transduction and has a beneficial effect of metabolism in skeletal muscle through direct activation of Akt and AMPK pathways.
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Affiliation(s)
- Thais de Castro Barbosa
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
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Giordanetto F, Karis D. Direct AMP-activated protein kinase activators: a review of evidence from the patent literature. Expert Opin Ther Pat 2012; 22:1467-77. [DOI: 10.1517/13543776.2012.743994] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Commentaries on Viewpoint: Maximal Na+-K+-ATPase activity is upregulated in association with muscle activity. J Appl Physiol (1985) 2012; 112:2124-6. [DOI: 10.1152/japplphysiol.00449.2012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Benziane B, Björnholm M, Pirkmajer S, Austin RL, Kotova O, Viollet B, Zierath JR, Chibalin AV. Activation of AMP-activated protein kinase stimulates Na+,K+-ATPase activity in skeletal muscle cells. J Biol Chem 2012; 287:23451-63. [PMID: 22610379 DOI: 10.1074/jbc.m111.331926] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Contraction stimulates Na(+),K(+)-ATPase and AMP-activated protein kinase (AMPK) activity in skeletal muscle. Whether AMPK activation affects Na(+),K(+)-ATPase activity in skeletal muscle remains to be determined. Short term stimulation of rat L6 myotubes with the AMPK activator 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR), activates AMPK and promotes translocation of the Na(+),K(+)-ATPase α(1)-subunit to the plasma membrane and increases Na(+),K(+)-ATPase activity as assessed by ouabain-sensitive (86)Rb(+) uptake. Cyanide-induced artificial anoxia, as well as a direct AMPK activator (A-769662) also increase AMPK phosphorylation and Na(+),K(+)-ATPase activity. Thus, different stimuli that target AMPK concomitantly increase Na(+),K(+)-ATPase activity. The effect of AICAR on Na(+),K(+)-ATPase in L6 myotubes was attenuated by Compound C, an AMPK inhibitor, as well as siRNA-mediated AMPK silencing. The effects of AICAR on Na(+),K(+)-ATPase were completely abolished in cultured primary mouse muscle cells lacking AMPK α-subunits. AMPK stimulation leads to Na(+),K(+)-ATPase α(1)-subunit dephosphorylation at Ser(18), which may prevent endocytosis of the sodium pump. AICAR stimulation leads to methylation and dephosphorylation of the catalytic subunit of the protein phosphatase (PP) 2A in L6 myotubes. Moreover, AICAR-triggered dephosphorylation of the Na(+),K(+)-ATPase was prevented in L6 myotubes deficient in PP2A-specific protein phosphatase methylesterase-1 (PME-1), indicating a role for the PP2A·PME-1 complex in AMPK-mediated regulation of Na(+),K(+)-ATPase. Thus contrary to the common paradigm, we report AMPK-dependent activation of an energy-consuming ion pumping process. This activation may be a potential mechanism by which exercise and metabolic stress activate the sodium pump in skeletal muscle.
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Affiliation(s)
- Boubacar Benziane
- Department of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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Vazquez-Martin A, Vellon L, Quirós PM, Cufí S, Ruiz de Galarreta E, Oliveras-Ferraros C, Martin AG, Martin-Castillo B, López-Otín C, Menendez JA. Activation of AMP-activated protein kinase (AMPK) provides a metabolic barrier to reprogramming somatic cells into stem cells. Cell Cycle 2012; 11:974-89. [PMID: 22333578 DOI: 10.4161/cc.11.5.19450] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The ability of somatic cells to reprogram their ATP-generating machinery into a Warburg-like glycolytic metabotype while overexpressing stemness genes facilitates their conversion into either induced pluripotent stem cells (iPSCs) or tumor-propagating cells. AMP-activated protein kinase (AMPK) is a metabolic master switch that senses and decodes intracellular changes in energy status; thus, we have evaluated the impact of AMPK activation in regulating the generation of iPSCs from nonstem cells of somatic origin. The indirect and direct activation of AMPK with the antidiabetic biguanide metformin and the thienopyridone A-769662, respectively, impeded the reprogramming of mouse embryonic and human diploid fibroblasts into iPSCs. The AMPK activators established a metabolic barrier to reprogramming that could not be bypassed, even through p53 deficiency, a fundamental mechanism to greatly improve the efficiency of stem-cell production. Treatment with metformin or A-769662 before the generation of iPSC colonies was sufficient to drastically decrease iPSC generation, suggesting that AMPK activation impedes early stem cell genetic reprogramming. Monitoring the transcriptional activation status of each individual reprogramming factor (i.e., Oct4, Sox2, Klf4 and c-Myc) revealed that AMPK activation notably prevented the transcriptional activation of Oct4, the master regulator of the pluripotent state. AMPK activation appears to impose a normalized metabolic flow away from the required pro-immortalizing glycolysis that fuels the induction of stemness and pluripotency, endowing somatic cells with an energetic infrastructure that is protected against reprogramming. AMPK-activating anti-reprogramming strategies may provide a roadmap for the generation of novel cancer therapies that metabolically target tumor-propagating cells.
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Abstract
Serum starvation is one of the most frequently performed procedures in molecular biology and there are literally thousands of research papers reporting its use. In fact, this method has become so ingrained in certain areas of research that reports often simply state that cells were serum starved without providing any factual details as to how the procedure was carried out. Even so, we quite obviously lack unequivocal terminology, standard protocols, and perhaps most surprisingly, a common conceptual basis when performing serum starvation. Such inconsistencies not only hinder interstudy comparability but can lead to opposing and inconsistent experimental results. Although it is frequently assumed that serum starvation reduces basal activity of cells, available experimental data do not entirely support this notion. To address this important issue, we studied primary human myotubes, rat L6 myotubes and human embryonic kidney (HEK)293 cells under different serum starvation conditions and followed time-dependent changes in important signaling pathways such as the extracellular signal-regulated kinase 1/2, the AMP-activated protein kinase, and the mammalian target of rapamycin. Serum starvation induced a swift and dynamic response, which displayed obvious qualitative and quantitative differences across different cell types and experimental conditions despite certain unifying features. There was no uniform reduction in basal signaling activity. Serum starvation clearly represents a major event that triggers a plethora of divergent responses and has therefore great potential to interfere with the experimental results and affect subsequent conclusions.
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Affiliation(s)
- Sergej Pirkmajer
- Department of Molecular Medicine and Surgery, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
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45
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Abstract
Neural circuits are especially vulnerable to metabolic stress. The locust (Locusta migratoria) responds to anoxia by entering a coma during which neural and muscular systems shut down. During anoxic coma, arrest of the ventilatory central pattern generator is tightly correlated with an abrupt spreading depression (SD)-like increase in extracellular potassium concentration within the metathoracic neuropile. We examined the role of the AMP-activated protein kinase (AMPK), an evolutionarily conserved sensor of cellular energy status, in anoxia-induced ventilatory arrest and SD-like events in the locust. Perfusion of sodium azide (NaN(3); mitochondrial toxin) induced SD, temporary coma, and profound changes in the ventilatory motor pattern characterized as a rapid rhythm before coma and a slower rhythm following recovery. AMPK activation using 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) mimicked the motor pattern changes induced by NaN(3) but did not induce SD and coma. The effects of NaN(3) on the ventilatory rhythm were reversed by perfusion of compound-C (AMPK inhibitor) or glucose, and the effects of AICAR were also reversed by compound-C, confirming the modulatory roles of AMPK and energy status. Ouabain-induced recurring SD was suppressed by inhibition of AMPK and exacerbated by its activation. We show that the motor pattern changes induced by metabolic stress are not the result of SD alone, but that AMPK is necessary and sufficient for these changes and that AMPK activity strongly influences susceptibility to SD.
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Yun H, Ha J. AMP-activated protein kinase modulators: a patent review (2006 - 2010). Expert Opin Ther Pat 2011; 21:983-1005. [PMID: 21548715 DOI: 10.1517/13543776.2011.577069] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
INTRODUCTION AMPK is a key player in the regulation of energy balance at both the cellular and whole-body levels, placing it at the center stage in studies of metabolic disorders. Recently, AMPK has also been identified as a potential target for either therapy or prevention of some types of cancer. Thus, identification of AMPK modulators for possible use as novel therapeutic drugs, both for treatment of metabolic disorders and cancer, will have a high commercial potential. AREAS COVERED This review covers the structures and activities of AMPK modulators described in the patent literature since 2006. The patents reviewed include those for direct and/or indirect activators of AMPK, and novel pharmaceutical compounds with potential for use in the prevention and/or treatment of metabolic disorders, and cancer targeting AMPK. EXPERT OPINION Targeting of AMPK appears to be an attractive strategy in the treatment of metabolic disorders. However, some detrimental effects of AMPK have also been reported, including a possible tumor-promoting effect in some settings and a heart disease-causing effect. Moreover, activation of AMPK in the hypothalamus may cause undesired consequences, such as an increase in feeding and body weight gain. These effects, therefore, must be carefully assessed for the development of therapeutic drugs targeting AMPK.
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Affiliation(s)
- Hee Yun
- Kyung Hee University, Medical Research Center and Biomedical Science Institute, School of Medicine, Department of Biochemistry and Molecular Biology, Seoul, Republic of Korea
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Lau GY, Richards JG. AMP-activated protein kinase plays a role in initiating metabolic rate suppression in goldfish hepatocytes. J Comp Physiol B 2011; 181:927-39. [DOI: 10.1007/s00360-011-0575-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Revised: 03/02/2011] [Accepted: 03/30/2011] [Indexed: 10/18/2022]
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Kim AS, Miller EJ, Wright TM, Li J, Qi D, Atsina K, Zaha V, Sakamoto K, Young LH. A small molecule AMPK activator protects the heart against ischemia-reperfusion injury. J Mol Cell Cardiol 2011; 51:24-32. [PMID: 21402077 DOI: 10.1016/j.yjmcc.2011.03.003] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 02/10/2011] [Accepted: 03/02/2011] [Indexed: 10/18/2022]
Abstract
AMP-activated protein kinase (AMPK) is a stress signaling enzyme that orchestrates the regulation of energy-generating and -consuming pathways. Intrinsic AMPK activation protects the heart against ischemic injury and apoptosis, but whether pharmacologic AMPK stimulation mitigates ischemia-reperfusion damage is unknown. The aims of this study were to determine whether direct stimulation of AMPK using a small molecule activator, A-769662, attenuates myocardial ischemia-reperfusion injury and to examine its cardioprotective mechanisms. Isolated mouse hearts pre-treated with A-769662 had better recovery of left ventricular contractile function (55% vs. 29% of baseline rate-pressure product; p=0.03) and less myocardial necrosis (56% reduction in infarct size; p<0.01) during post-ischemic reperfusion compared to control hearts. Pre-treatment with A-769662 in vivo attenuated infarct size in C57Bl/6 mice undergoing left coronary artery occlusion and reperfusion compared to vehicle (36% vs. 18%, p=0.025). Mouse hearts with genetically inactivated AMPK were not protected by A-769662, indicating the specificity of this compound. Pre-treatment with A-769662 increased the phosphorylation and inactivation of eukaryotic elongation factor 2 (eEF2), preserved energy charge during ischemia, delayed the development of ischemic contracture, and reduced myocardial apoptosis and necrosis. A-769662 also augmented endothelial nitric oxide synthase (eNOS) activation during ischemia, which partially attenuated myocardial stunning, but did not prevent necrosis. AMPK is a therapeutic target that can be stimulated by a direct-acting small molecule in order to prevent injury during ischemia-reperfusion. The use of AMPK activators may represent a novel strategy to protect the heart and other solid organs against ischemia.
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Affiliation(s)
- Agnes S Kim
- Yale University School of Medicine, Section of Cardiovascular Medicine, 333 Cedar Street, New Haven, CT 06510, USA
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Paiva MA, Rutter-Locher Z, Gonçalves LM, Providência LA, Davidson SM, Yellon DM, Mocanu MM. Enhancing AMPK activation during ischemia protects the diabetic heart against reperfusion injury. Am J Physiol Heart Circ Physiol 2011; 300:H2123-34. [PMID: 21421816 DOI: 10.1152/ajpheart.00707.2010] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
AMPK activation during ischemia helps the myocardium to cope with the deficit of energy production. As AMPK activity is considered to be impaired in diabetes, we hypothesized that enhancing AMPK activation during ischemia above physiological levels would protect the ischemic diabetic heart through AMPK activation and subsequent inhibition of mitochondrial permeability transition pore (mPTP) opening. Isolated perfused hearts from normoglycemic Wistar or diabetic Goto-Kakizaki (GK) rats (n ≥ 6/group) were subjected to 35 min of ischemia in the presence of 10, 20, and 40 μM of A-769662, a known activator of AMPK, followed by 120 min of reperfusion with normal buffer. Myocardial infarction and AMPK phosphorylation were assessed. The effect of A-769662 on mPTP opening in adult cardiomyocytes isolated from both strains was also determined. A-769662 at 20 μM reduced infarct size in both Wistar (30.5 ± 2.7 vs. 51.8 ± 3.9% vehicle; P < 0.001) and GK hearts (22.7 ± 3.0 vs. 48.5 ± 4.7% vehicle; P < 0.001). This protection was accompanied by a significant increase in AMPK and GSK-3β phosphorylation. In addition, A-769662 significantly inhibited mPTP opening in both Wistar and GK cardiomyocytes subjected to oxidative stress. We demonstrate that AMPK activation during ischemia via A-769662 reduces myocardial infarct size in both the nondiabetic and diabetic rat heart. Furthermore, this cardioprotective effect appears to be mediated through inhibition of mPTP opening. Our findings suggest that improving AMPK activation during ischemia can be another mechanism for protecting the ischemic heart.
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Affiliation(s)
- Marta A Paiva
- Hatter Cardiovascular Institute, Univ. College London Hospitals, 67 Chenies Mews, London, WC1E 6HX, UK
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Abstract
Exercise, together with a low-energy diet, is the first-line treatment for type 2 diabetes type 2 diabetes . Exercise improves insulin sensitivity insulin sensitivity by increasing the number or function of muscle mitochondria mitochondria and the capacity for aerobic metabolism, all of which are low in many insulin-resistant subjects. Cannabinoid 1-receptor antagonists and β-adrenoceptor agonists improve insulin sensitivity in humans and promote fat oxidation in rodents independently of reduced food intake. Current drugs for the treatment of diabetes are not, however, noted for their ability to increase fat oxidation, although the thiazolidinediones increase the capacity for fat oxidation in skeletal muscle, whilst paradoxically increasing weight gain.There are a number of targets for anti-diabetic drugs that may improve insulin sensitivity insulin sensitivity by increasing the capacity for fat oxidation. Their mechanisms of action are linked, notably through AMP-activated protein kinase, adiponectin, and the sympathetic nervous system. If ligands for these targets have obvious acute thermogenic activity, it is often because they increase sympathetic activity. This promotes fuel mobilisation, as well as fuel oxidation. When thermogenesis thermogenesis is not obvious, researchers often argue that it has occurred by using the inappropriate device of treating animals for days or weeks until there is weight (mainly fat) loss and then expressing energy expenditure energy expenditure relative to body weight. In reality, thermogenesis may have occurred, but it is too small to detect, and this device distracts us from really appreciating why insulin sensitivity has improved. This is that by increasing fatty acid oxidation fatty acid oxidation more than fatty acid supply, drugs lower the concentrations of fatty acid metabolites that cause insulin resistance. Insulin sensitivity improves long before any anti-obesity effect can be detected.
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Affiliation(s)
- Jonathan R S Arch
- Clore Laboratory, University of Buckingham, Buckingham, MK18 1EG, UK
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